Merge tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
"Here is the set of driver core changes for 5.19-rc1.

Lots of tiny driver core changes and cleanups happened this cycle, but
the two major things are:

- firmware_loader reorganization and additions including the ability
to have XZ compressed firmware images and the ability for userspace
to initiate the firmware load when it needs to, instead of being
always initiated by the kernel. FPGA devices specifically want this
ability to have their firmware changed over the lifetime of the
system boot, and this allows them to work without having to come up
with yet-another-custom-uapi interface for loading firmware for
them.

- physical location support added to sysfs so that devices that know
this information, can tell userspace where they are located in a
common way. Some ACPI devices already support this today, and more
bus types should support this in the future.

Smaller changes include:

- driver_override api cleanups and fixes

- error path cleanups and fixes

- get_abi script fixes

- deferred probe timeout changes.

It's that last change that I'm the most worried about. It has been
reported to cause boot problems for a number of systems, and I have a
tested patch series that resolves this issue. But I didn't get it
merged into my tree before 5.18-final came out, so it has not gotten
any linux-next testing.

I'll send the fixup patches (there are 2) as a follow-on series to this
pull request.

All have been tested in linux-next for weeks, with no reported issues
other than the above-mentioned boot time-outs"

* tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
driver core: fix deadlock in __device_attach
kernfs: Separate kernfs_pr_cont_buf and rename_lock.
topology: Remove unused cpu_cluster_mask()
driver core: Extend deferred probe timeout on driver registration
MAINTAINERS: add Russ Weight as a firmware loader maintainer
driver: base: fix UAF when driver_attach failed
test_firmware: fix end of loop test in upload_read_show()
driver core: location: Add "back" as a possible output for panel
driver core: location: Free struct acpi_pld_info *pld
driver core: Add "*" wildcard support to driver_async_probe cmdline param
driver core: location: Check for allocations failure
arch_topology: Trace the update thermal pressure
kernfs: Rename kernfs_put_open_node to kernfs_unlink_open_file.
export: fix string handling of namespace in EXPORT_SYMBOL_NS
rpmsg: use local 'dev' variable
rpmsg: Fix calling device_lock() on non-initialized device
firmware_loader: describe 'module' parameter of firmware_upload_register()
firmware_loader: Move definitions from sysfs_upload.h to sysfs.h
firmware_loader: Fix configs for sysfs split
selftests: firmware: Add firmware upload selftests
...

Documentation/ABI/testing/sysfs-class-firmware

···
+What: 		/sys/class/firmware/.../data
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	The data sysfs file is used for firmware-fallback and for
+		firmware uploads. Cat a firmware image to this sysfs file
+		after you echo 1 to the loading sysfs file. When the firmware
+		image write is complete, echo 0 to the loading sysfs file. This
+		sequence will signal the completion of the firmware write and
+		signal the lower-level driver that the firmware data is
+		available.
+
+What: 		/sys/class/firmware/.../cancel
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	Write-only. For firmware uploads, write a "1" to this file to
+		request that the transfer of firmware data to the lower-level
+		device be canceled. This request will be rejected (EBUSY) if
+		the update cannot be canceled (e.g. a FLASH write is in
+		progress) or (ENODEV) if there is no firmware update in progress.
+
+What: 		/sys/class/firmware/.../error
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	Read-only. Returns a string describing a failed firmware
+		upload. This string will be in the form of <STATUS>:<ERROR>,
+		where <STATUS> will be one of the status strings described
+		for the status sysfs file and <ERROR> will be one of the
+		following: "hw-error", "timeout", "user-abort", "device-busy",
+		"invalid-file-size", "read-write-error", "flash-wearout". The
+		error sysfs file is only meaningful when the current firmware
+		upload status is "idle". If this file is read while a firmware
+		transfer is in progress, then the read will fail with EBUSY.
+
+What: 		/sys/class/firmware/.../loading
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	The loading sysfs file is used for both firmware-fallback and
+		for firmware uploads. Echo 1 onto the loading file to indicate
+		you are writing a firmware file to the data sysfs node. Echo
+		-1 onto this file to abort the data write or echo 0 onto this
+		file to indicate that the write is complete. For firmware
+		uploads, the zero value also triggers the transfer of the
+		firmware data to the lower-level device driver.
+
+What: 		/sys/class/firmware/.../remaining_size
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	Read-only. For firmware upload, this file contains the size
+		of the firmware data that remains to be transferred to the
+		lower-level device driver. The size value is initialized to
+		the full size of the firmware image that was previously
+		written to the data sysfs file. This value is periodically
+		updated during the "transferring" phase of the firmware
+		upload.
+		Format: "%u".
+
+What: 		/sys/class/firmware/.../status
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	Read-only. Returns a string describing the current status of
+		a firmware upload. The string will be one of the following:
+		idle, "receiving", "preparing", "transferring", "programming".
+
+What: 		/sys/class/firmware/.../timeout
+Date:		July 2022
+KernelVersion:	5.19
+Contact:	Russ Weight <[e-mail]>
+Description:	This file supports the timeout mechanism for firmware
+		fallback.  This file has no affect on firmware uploads. For
+		more information on timeouts please see the documentation
+		for firmware fallback.

Documentation/ABI/testing/sysfs-devices-physical_location

···
+What:		/sys/devices/.../physical_location
+Date:		March 2022
+Contact:	Won Chung <[e-mail]>
+Description:
+		This directory contains information on physical location of
+		the device connection point with respect to the system's
+		housing.
+
+What:		/sys/devices/.../physical_location/panel
+Date:		March 2022
+Contact:	Won Chung <[e-mail]>
+Description:
+		Describes which panel surface of the system’s housing the
+		device connection point resides on.
+
+What:		/sys/devices/.../physical_location/vertical_position
+Date:		March 2022
+Contact:	Won Chung <[e-mail]>
+Description:
+		Describes vertical position of the device connection point on
+		the panel surface.
+
+What:		/sys/devices/.../physical_location/horizontal_position
+Date:		March 2022
+Contact:	Won Chung <[e-mail]>
+Description:
+		Describes horizontal position of the device connection point on
+		the panel surface.
+
+What:		/sys/devices/.../physical_location/dock
+Date:		March 2022
+Contact:	Won Chung <[e-mail]>
+Description:
+		"Yes" if the device connection point resides in a docking
+		station or a port replicator. "No" otherwise.
+
+What:		/sys/devices/.../physical_location/lid
+Date:		March 2022
+Contact:	Won Chung <[e-mail]>
+Description:
+		"Yes" if the device connection point resides on the lid of
+		laptop system. "No" otherwise.

Documentation/admin-guide/kernel-parameters.txt

···
 			[KNL] Debugging option to set a timeout in seconds for
 			deferred probe to give up waiting on dependencies to
 			probe. Only specific dependencies (subsystems or
-			drivers) that have opted in will be ignored. A timeout of 0
-			will timeout at the end of initcalls. This option will also
+			drivers) that have opted in will be ignored. A timeout
+			of 0 will timeout at the end of initcalls. If the time
+			out hasn't expired, it'll be restarted by each
+			successful driver registration. This option will also
 			dump out devices still on the deferred probe list after
 			retrying.
 
···
 			driver later using sysfs.
 
 	driver_async_probe=  [KNL]
-			List of driver names to be probed asynchronously.
+			List of driver names to be probed asynchronously. *
+			matches with all driver names. If * is specified, the
+			rest of the listed driver names are those that will NOT
+			match the *.
 			Format: <driver_name1>,<driver_name2>...
 
 	drm.edid_firmware=[<connector>:]<file>[,[<connector>:]<file>]

Documentation/driver-api/firmware/fw_upload.rst

···
+.. SPDX-License-Identifier: GPL-2.0
+
+===================
+Firmware Upload API
+===================
+
+A device driver that registers with the firmware loader will expose
+persistent sysfs nodes to enable users to initiate firmware updates for
+that device.  It is the responsibility of the device driver and/or the
+device itself to perform any validation on the data received. Firmware
+upload uses the same *loading* and *data* sysfs files described in the
+documentation for firmware fallback. It also adds additional sysfs files
+to provide status on the transfer of the firmware image to the device.
+
+Register for firmware upload
+============================
+
+A device driver registers for firmware upload by calling
+firmware_upload_register(). Among the parameter list is a name to
+identify the device under /sys/class/firmware. A user may initiate a
+firmware upload by echoing a 1 to the *loading* sysfs file for the target
+device. Next, the user writes the firmware image to the *data* sysfs
+file. After writing the firmware data, the user echos 0 to the *loading*
+sysfs file to signal completion. Echoing 0 to *loading* also triggers the
+transfer of the firmware to the lower-lever device driver in the context
+of a kernel worker thread.
+
+To use the firmware upload API, write a driver that implements a set of
+ops.  The probe function calls firmware_upload_register() and the remove
+function calls firmware_upload_unregister() such as::
+
+	static const struct fw_upload_ops m10bmc_ops = {
+		.prepare = m10bmc_sec_prepare,
+		.write = m10bmc_sec_write,
+		.poll_complete = m10bmc_sec_poll_complete,
+		.cancel = m10bmc_sec_cancel,
+		.cleanup = m10bmc_sec_cleanup,
+	};
+
+	static int m10bmc_sec_probe(struct platform_device *pdev)
+	{
+		const char *fw_name, *truncate;
+		struct m10bmc_sec *sec;
+		struct fw_upload *fwl;
+		unsigned int len;
+
+		sec = devm_kzalloc(&pdev->dev, sizeof(*sec), GFP_KERNEL);
+		if (!sec)
+			return -ENOMEM;
+
+		sec->dev = &pdev->dev;
+		sec->m10bmc = dev_get_drvdata(pdev->dev.parent);
+		dev_set_drvdata(&pdev->dev, sec);
+
+		fw_name = dev_name(sec->dev);
+		truncate = strstr(fw_name, ".auto");
+		len = (truncate) ? truncate - fw_name : strlen(fw_name);
+		sec->fw_name = kmemdup_nul(fw_name, len, GFP_KERNEL);
+
+		fwl = firmware_upload_register(sec->dev, sec->fw_name, &m10bmc_ops, sec);
+		if (IS_ERR(fwl)) {
+			dev_err(sec->dev, "Firmware Upload driver failed to start\n");
+			kfree(sec->fw_name);
+			return PTR_ERR(fwl);
+		}
+
+		sec->fwl = fwl;
+		return 0;
+	}
+
+	static int m10bmc_sec_remove(struct platform_device *pdev)
+	{
+		struct m10bmc_sec *sec = dev_get_drvdata(&pdev->dev);
+
+		firmware_upload_unregister(sec->fwl);
+		kfree(sec->fw_name);
+		return 0;
+	}
+
+firmware_upload_register
+------------------------
+.. kernel-doc:: drivers/base/firmware_loader/sysfs_upload.c
+   :identifiers: firmware_upload_register
+
+firmware_upload_unregister
+--------------------------
+.. kernel-doc:: drivers/base/firmware_loader/sysfs_upload.c
+   :identifiers: firmware_upload_unregister
+
+Firmware Upload Ops
+-------------------
+.. kernel-doc:: include/linux/firmware.h
+   :identifiers: fw_upload_ops
+
+Firmware Upload Progress Codes
+------------------------------
+The following progress codes are used internally by the firmware loader.
+Corresponding strings are reported through the status sysfs node that
+is described below and are documented in the ABI documentation.
+
+.. kernel-doc:: drivers/base/firmware_loader/sysfs_upload.h
+   :identifiers: fw_upload_prog
+
+Firmware Upload Error Codes
+---------------------------
+The following error codes may be returned by the driver ops in case of
+failure:
+
+.. kernel-doc:: include/linux/firmware.h
+   :identifiers: fw_upload_err
+
+Sysfs Attributes
+================
+
+In addition to the *loading* and *data* sysfs files, there are additional
+sysfs files to monitor the status of the data transfer to the target
+device and to determine the final pass/fail status of the transfer.
+Depending on the device and the size of the firmware image, a firmware
+update could take milliseconds or minutes.
+
+The additional sysfs files are:
+
+* status - provides an indication of the progress of a firmware update
+* error - provides error information for a failed firmware update
+* remaining_size - tracks the data transfer portion of an update
+* cancel - echo 1 to this file to cancel the update

Documentation/driver-api/firmware/index.rst

···
    core
    efi/index
    request_firmware
+   fw_upload
    other_interfaces
 
 .. only::  subproject and html

MAINTAINERS

···
 
 FIRMWARE LOADER (request_firmware)
 M:	Luis Chamberlain <[e-mail]>
+M:	Russ Weight <[e-mail]>
 L:	[e-mail]
 S:	Maintained
 F:	Documentation/firmware_class/

drivers/amba/bus.c

···
 				     const char *buf, size_t count)
 {
 	struct amba_device *dev = to_amba_device(_dev);
-	char *driver_override, *old, *cp;
+	int ret;
 
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(_dev);
-	old = dev->driver_override;
-	if (strlen(driver_override)) {
-		dev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		dev->driver_override = NULL;
-	}
-	device_unlock(_dev);
-
-	kfree(old);
+	ret = driver_set_override(_dev, &dev->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/base/Makefile

···
 obj-$(CONFIG_GENERIC_MSI_IRQ_DOMAIN) += platform-msi.o
 obj-$(CONFIG_GENERIC_ARCH_TOPOLOGY) += arch_topology.o
 obj-$(CONFIG_GENERIC_ARCH_NUMA) += arch_numa.o
+obj-$(CONFIG_ACPI) += physical_location.o
 
 obj-y			+= test/
 

drivers/base/arch_topology.c

···
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/thermal_pressure.h>
+
 static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data);
 static struct cpumask scale_freq_counters_mask;
 static bool scale_freq_invariant;
···
 		capacity = mult_frac(max_capacity, capped_freq, max_freq);
 
 	th_pressure = max_capacity - capacity;
+
+	trace_thermal_pressure_update(cpu, th_pressure);
 
 	for_each_cpu(cpu, cpus)
 		WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);

drivers/base/base.h

···
 extern int devres_release_all(struct device *dev);
 extern void device_block_probing(void);
 extern void device_unblock_probing(void);
+extern void deferred_probe_extend_timeout(void);
 
 /* /sys/devices directory */
 extern struct kset *devices_kset;

drivers/base/bus.c

···
 	if (drv->bus->p->drivers_autoprobe) {
 		error = driver_attach(drv);
 		if (error)
-			goto out_unregister;
+			goto out_del_list;
 	}
 	module_add_driver(drv->owner, drv);
 
···
 
 	return 0;
 
+out_del_list:
+	klist_del(&priv->knode_bus);
 out_unregister:
 	kobject_put(&priv->kobj);
 	/* drv->p is freed in driver_release()  */

drivers/base/core.c

···
 #include <linux/dma-map-ops.h> /* for dma_default_coherent */
 
 #include "base.h"
+#include "physical_location.h"
 #include "power/power.h"
 
 #ifdef CONFIG_SYSFS_DEPRECATED
···
 			goto err_remove_dev_waiting_for_supplier;
 	}
 
+	if (dev_add_physical_location(dev)) {
+		error = device_add_group(dev,
+			&dev_attr_physical_location_group);
+		if (error)
+			goto err_remove_dev_removable;
+	}
+
 	return 0;
 
+ err_remove_dev_removable:
+	device_remove_file(dev, &dev_attr_removable);
  err_remove_dev_waiting_for_supplier:
 	device_remove_file(dev, &dev_attr_waiting_for_supplier);
  err_remove_dev_online:
···
 {
 	struct class *class = dev->class;
 	const struct device_type *type = dev->type;
+
+	if (dev->physical_location) {
+		device_remove_group(dev, &dev_attr_physical_location_group);
+		kfree(dev->physical_location);
+	}
 
 	device_remove_file(dev, &dev_attr_removable);
 	device_remove_file(dev, &dev_attr_waiting_for_supplier);

drivers/base/dd.c

···
 /* Save the async probe drivers' name from kernel cmdline */
 #define ASYNC_DRV_NAMES_MAX_LEN	256
 static char async_probe_drv_names[ASYNC_DRV_NAMES_MAX_LEN];
+static bool async_probe_default;
 
 /*
  * In some cases, like suspend to RAM or hibernation, It might be reasonable
···
 }
 DEFINE_SHOW_ATTRIBUTE(deferred_devs);
 
+#ifdef CONFIG_MODULES
+int driver_deferred_probe_timeout = 10;
+#else
 int driver_deferred_probe_timeout;
+#endif
+
 EXPORT_SYMBOL_GPL(driver_deferred_probe_timeout);
 static DECLARE_WAIT_QUEUE_HEAD(probe_timeout_waitqueue);
 
···
  * @dev: device to check
  *
  * Return:
- * -ENODEV if initcalls have completed and modules are disabled.
- * -ETIMEDOUT if the deferred probe timeout was set and has expired
- *  and modules are enabled.
- * -EPROBE_DEFER in other cases.
+ * * -ENODEV if initcalls have completed and modules are disabled.
+ * * -ETIMEDOUT if the deferred probe timeout was set and has expired
+ *   and modules are enabled.
+ * * -EPROBE_DEFER in other cases.
  *
  * Drivers or subsystems can opt-in to calling this function instead of directly
  * returning -EPROBE_DEFER.
···
 	wake_up_all(&probe_timeout_waitqueue);
 }
 static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func);
+
+void deferred_probe_extend_timeout(void)
+{
+	/*
+	 * If the work hasn't been queued yet or if the work expired, don't
+	 * start a new one.
+	 */
+	if (cancel_delayed_work(&deferred_probe_timeout_work)) {
+		schedule_delayed_work(&deferred_probe_timeout_work,
+				driver_deferred_probe_timeout * HZ);
+		pr_debug("Extended deferred probe timeout by %d secs\n",
+					driver_deferred_probe_timeout);
+	}
+}
 
 /**
  * deferred_probe_initcall() - Enable probing of deferred devices
···
 
 static inline bool cmdline_requested_async_probing(const char *drv_name)
 {
-	return parse_option_str(async_probe_drv_names, drv_name);
+	bool async_drv;
+
+	async_drv = parse_option_str(async_probe_drv_names, drv_name);
+
+	return (async_probe_default != async_drv);
 }
 
 /* The option format is "driver_async_probe=drv_name1,drv_name2,..." */
···
 		pr_warn("Too long list of driver names for 'driver_async_probe'!\n");
 
 	strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN);
+	async_probe_default = parse_option_str(async_probe_drv_names, "*");
+
 	return 1;
 }
 __setup("driver_async_probe=", save_async_options);
···
 static int __device_attach(struct device *dev, bool allow_async)
 {
 	int ret = 0;
+	bool async = false;
 
 	device_lock(dev);
 	if (dev->p->dead) {
···
 			 */
 			dev_dbg(dev, "scheduling asynchronous probe\n");
 			get_device(dev);
-			async_schedule_dev(__device_attach_async_helper, dev);
+			async = true;
 		} else {
 			pm_request_idle(dev);
 		}
···
 	}
 out_unlock:
 	device_unlock(dev);
+	if (async)
+		async_schedule_dev(__device_attach_async_helper, dev);
 	return ret;
 }
 
···
 
 	__device_driver_lock(dev, dev->parent);
 	drv = dev->p->async_driver;
+	dev->p->async_driver = NULL;
 	ret = driver_probe_device(drv, dev);
 	__device_driver_unlock(dev, dev->parent);
 
···
 		 */
 		dev_dbg(dev, "probing driver %s asynchronously\n", drv->name);
 		device_lock(dev);
-		if (!dev->driver) {
+		if (!dev->driver && !dev->p->async_driver) {
 			get_device(dev);
 			dev->p->async_driver = drv;
 			async_schedule_dev(__driver_attach_async_helper, dev);

drivers/base/driver.c

···
 }
 
 /**
+ * driver_set_override() - Helper to set or clear driver override.
+ * @dev: Device to change
+ * @override: Address of string to change (e.g. &device->driver_override);
+ *            The contents will be freed and hold newly allocated override.
+ * @s: NUL-terminated string, new driver name to force a match, pass empty
+ *     string to clear it ("" or "\n", where the latter is only for sysfs
+ *     interface).
+ * @len: length of @s
+ *
+ * Helper to set or clear driver override in a device, intended for the cases
+ * when the driver_override field is allocated by driver/bus code.
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+int driver_set_override(struct device *dev, const char **override,
+			const char *s, size_t len)
+{
+	const char *new, *old;
+	char *cp;
+
+	if (!override || !s)
+		return -EINVAL;
+
+	/*
+	 * The stored value will be used in sysfs show callback (sysfs_emit()),
+	 * which has a length limit of PAGE_SIZE and adds a trailing newline.
+	 * Thus we can store one character less to avoid truncation during sysfs
+	 * show.
+	 */
+	if (len >= (PAGE_SIZE - 1))
+		return -EINVAL;
+
+	if (!len) {
+		/* Empty string passed - clear override */
+		device_lock(dev);
+		old = *override;
+		*override = NULL;
+		device_unlock(dev);
+		kfree(old);
+
+		return 0;
+	}
+
+	cp = strnchr(s, len, '\n');
+	if (cp)
+		len = cp - s;
+
+	new = kstrndup(s, len, GFP_KERNEL);
+	if (!new)
+		return -ENOMEM;
+
+	device_lock(dev);
+	old = *override;
+	if (cp != s) {
+		*override = new;
+	} else {
+		/* "\n" passed - clear override */
+		kfree(new);
+		*override = NULL;
+	}
+	device_unlock(dev);
+
+	kfree(old);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(driver_set_override);
+
+/**
  * driver_for_each_device - Iterator for devices bound to a driver.
  * @drv: Driver we're iterating.
  * @start: Device to begin with
···
 		return ret;
 	}
 	kobject_uevent(&drv->p->kobj, KOBJ_ADD);
+	deferred_probe_extend_timeout();
 
 	return ret;
 }

drivers/base/firmware_loader/Kconfig

···
 config FW_LOADER_PAGED_BUF
 	bool
 
+config FW_LOADER_SYSFS
+	bool
+
 config EXTRA_FIRMWARE
 	string "Build named firmware blobs into the kernel binary"
 	help
···
 
 config FW_LOADER_USER_HELPER
 	bool "Enable the firmware sysfs fallback mechanism"
+	select FW_LOADER_SYSFS
 	select FW_LOADER_PAGED_BUF
 	help
 	  This option enables a sysfs loading facility to enable firmware
···
 
 config FW_LOADER_COMPRESS
 	bool "Enable compressed firmware support"
-	select FW_LOADER_PAGED_BUF
-	select XZ_DEC
 	help
 	  This option enables the support for loading compressed firmware
 	  files. The caller of firmware API receives the decompressed file
 	  content. The compressed file is loaded as a fallback, only after
 	  loading the raw file failed at first.
 
-	  Currently only XZ-compressed files are supported, and they have to
-	  be compressed with either none or crc32 integrity check type (pass
-	  "-C crc32" option to xz command).
-
 	  Compressed firmware support does not apply to firmware images
 	  that are built into the kernel image (CONFIG_EXTRA_FIRMWARE).
+
+if FW_LOADER_COMPRESS
+config FW_LOADER_COMPRESS_XZ
+	bool "Enable XZ-compressed firmware support"
+	select FW_LOADER_PAGED_BUF
+	select XZ_DEC
+	help
+	  This option adds the support for XZ-compressed files.
+	  The files have to be compressed with either none or crc32
+	  integrity check type (pass "-C crc32" option to xz command).
+
+config FW_LOADER_COMPRESS_ZSTD
+	bool "Enable ZSTD-compressed firmware support"
+	select ZSTD_DECOMPRESS
+	help
+	  This option adds the support for ZSTD-compressed files.
+
+endif # FW_LOADER_COMPRESS
 
 config FW_CACHE
 	bool "Enable firmware caching during suspend"
···
 	  option.
 
 	  If unsure, say Y.
+
+config FW_UPLOAD
+	bool "Enable users to initiate firmware updates using sysfs"
+	select FW_LOADER_SYSFS
+	select FW_LOADER_PAGED_BUF
+	help
+	  Enabling this option will allow device drivers to expose a persistent
+	  sysfs interface that allows firmware updates to be initiated from
+	  userspace. For example, FPGA based PCIe cards load firmware and FPGA
+	  images from local FLASH when the card boots. The images in FLASH may
+	  be updated with new images provided by the user. Enable this device
+	  to support cards that rely on user-initiated updates for firmware files.
+
+	  If unsure, say N.
 
 endif # FW_LOADER
 endmenu

drivers/base/firmware_loader/Makefile

···
 firmware_class-objs := main.o
 firmware_class-$(CONFIG_FW_LOADER_USER_HELPER) += fallback.o
 firmware_class-$(CONFIG_EFI_EMBEDDED_FIRMWARE) += fallback_platform.o
+firmware_class-$(CONFIG_FW_LOADER_SYSFS) += sysfs.o
+firmware_class-$(CONFIG_FW_UPLOAD) += sysfs_upload.o
 
 obj-y += builtin/

drivers/base/firmware_loader/fallback.c

···
 #include <linux/types.h>
 #include <linux/kconfig.h>
 #include <linux/list.h>
-#include <linux/slab.h>
 #include <linux/security.h>
-#include <linux/highmem.h>
 #include <linux/umh.h>
 #include <linux/sysctl.h>
-#include <linux/vmalloc.h>
 #include <linux/module.h>
 
 #include "fallback.h"
···
 /*
  * firmware fallback mechanism
  */
-
-MODULE_IMPORT_NS(FIRMWARE_LOADER_PRIVATE);
-
-extern struct firmware_fallback_config fw_fallback_config;
-
-/* These getters are vetted to use int properly */
-static inline int __firmware_loading_timeout(void)
-{
-	return fw_fallback_config.loading_timeout;
-}
-
-/* These setters are vetted to use int properly */
-static void __fw_fallback_set_timeout(int timeout)
-{
-	fw_fallback_config.loading_timeout = timeout;
-}
 
 /*
  * use small loading timeout for caching devices' firmware because all these
···
 		__firmware_loading_timeout() * HZ : MAX_JIFFY_OFFSET;
 }
 
-static inline bool fw_sysfs_done(struct fw_priv *fw_priv)
-{
-	return __fw_state_check(fw_priv, FW_STATUS_DONE);
-}
-
-static inline bool fw_sysfs_loading(struct fw_priv *fw_priv)
-{
-	return __fw_state_check(fw_priv, FW_STATUS_LOADING);
-}
-
 static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv,  long timeout)
 {
 	return __fw_state_wait_common(fw_priv, timeout);
-}
-
-struct fw_sysfs {
-	bool nowait;
-	struct device dev;
-	struct fw_priv *fw_priv;
-	struct firmware *fw;
-};
-
-static struct fw_sysfs *to_fw_sysfs(struct device *dev)
-{
-	return container_of(dev, struct fw_sysfs, dev);
-}
-
-static void __fw_load_abort(struct fw_priv *fw_priv)
-{
-	/*
-	 * There is a small window in which user can write to 'loading'
-	 * between loading done/aborted and disappearance of 'loading'
-	 */
-	if (fw_state_is_aborted(fw_priv) || fw_sysfs_done(fw_priv))
-		return;
-
-	fw_state_aborted(fw_priv);
-}
-
-static void fw_load_abort(struct fw_sysfs *fw_sysfs)
-{
-	struct fw_priv *fw_priv = fw_sysfs->fw_priv;
-
-	__fw_load_abort(fw_priv);
 }
 
 static LIST_HEAD(pending_fw_head);
···
 			 __fw_load_abort(fw_priv);
 	}
 	mutex_unlock(&fw_lock);
-}
-
-static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
-			    char *buf)
-{
-	return sysfs_emit(buf, "%d\n", __firmware_loading_timeout());
-}
-
-/**
- * timeout_store() - set number of seconds to wait for firmware
- * @class: device class pointer
- * @attr: device attribute pointer
- * @buf: buffer to scan for timeout value
- * @count: number of bytes in @buf
- *
- *	Sets the number of seconds to wait for the firmware.  Once
- *	this expires an error will be returned to the driver and no
- *	firmware will be provided.
- *
- *	Note: zero means 'wait forever'.
- **/
-static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
-			     const char *buf, size_t count)
-{
-	int tmp_loading_timeout = simple_strtol(buf, NULL, 10);
-
-	if (tmp_loading_timeout < 0)
-		tmp_loading_timeout = 0;
-
-	__fw_fallback_set_timeout(tmp_loading_timeout);
-
-	return count;
-}
-static CLASS_ATTR_RW(timeout);
-
-static struct attribute *firmware_class_attrs[] = {
-	&class_attr_timeout.attr,
-	NULL,
-};
-ATTRIBUTE_GROUPS(firmware_class);
-
-static void fw_dev_release(struct device *dev)
-{
-	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
-
-	kfree(fw_sysfs);
-}
-
-static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env)
-{
-	if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name))
-		return -ENOMEM;
-	if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout()))
-		return -ENOMEM;
-	if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait))
-		return -ENOMEM;
-
-	return 0;
-}
-
-static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
-	int err = 0;
-
-	mutex_lock(&fw_lock);
-	if (fw_sysfs->fw_priv)
-		err = do_firmware_uevent(fw_sysfs, env);
-	mutex_unlock(&fw_lock);
-	return err;
-}
-
-static struct class firmware_class = {
-	.name		= "firmware",
-	.class_groups	= firmware_class_groups,
-	.dev_uevent	= firmware_uevent,
-	.dev_release	= fw_dev_release,
-};
-
-int register_sysfs_loader(void)
-{
-	int ret = class_register(&firmware_class);
-
-	if (ret != 0)
-		return ret;
-	return register_firmware_config_sysctl();
-}
-
-void unregister_sysfs_loader(void)
-{
-	unregister_firmware_config_sysctl();
-	class_unregister(&firmware_class);
-}
-
-static ssize_t firmware_loading_show(struct device *dev,
-				     struct device_attribute *attr, char *buf)
-{
-	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
-	int loading = 0;
-
-	mutex_lock(&fw_lock);
-	if (fw_sysfs->fw_priv)
-		loading = fw_sysfs_loading(fw_sysfs->fw_priv);
-	mutex_unlock(&fw_lock);
-
-	return sysfs_emit(buf, "%d\n", loading);
-}
-
-/**
- * firmware_loading_store() - set value in the 'loading' control file
- * @dev: device pointer
- * @attr: device attribute pointer
- * @buf: buffer to scan for loading control value
- * @count: number of bytes in @buf
- *
- *	The relevant values are:
- *
- *	 1: Start a load, discarding any previous partial load.
- *	 0: Conclude the load and hand the data to the driver code.
- *	-1: Conclude the load with an error and discard any written data.
- **/
-static ssize_t firmware_loading_store(struct device *dev,
-				      struct device_attribute *attr,
-				      const char *buf, size_t count)
-{
-	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
-	struct fw_priv *fw_priv;
-	ssize_t written = count;
-	int loading = simple_strtol(buf, NULL, 10);
-
-	mutex_lock(&fw_lock);
-	fw_priv = fw_sysfs->fw_priv;
-	if (fw_state_is_aborted(fw_priv))
-		goto out;
-
-	switch (loading) {
-	case 1:
-		/* discarding any previous partial load */
-		if (!fw_sysfs_done(fw_priv)) {
-			fw_free_paged_buf(fw_priv);
-			fw_state_start(fw_priv);
-		}
-		break;
-	case 0:
-		if (fw_sysfs_loading(fw_priv)) {
-			int rc;
-
-			/*
-			 * Several loading requests may be pending on
-			 * one same firmware buf, so let all requests
-			 * see the mapped 'buf->data' once the loading
-			 * is completed.
-			 * */
-			rc = fw_map_paged_buf(fw_priv);
-			if (rc)
-				dev_err(dev, "%s: map pages failed\n",
-					__func__);
-			else
-				rc = security_kernel_post_load_data(fw_priv->data,
-						fw_priv->size,
-						LOADING_FIRMWARE, "blob");
-
-			/*
-			 * Same logic as fw_load_abort, only the DONE bit
-			 * is ignored and we set ABORT only on failure.
-			 */
-			if (rc) {
-				fw_state_aborted(fw_priv);
-				written = rc;
-			} else {
-				fw_state_done(fw_priv);
-			}
-			break;
-		}
-		fallthrough;
-	default:
-		dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
-		fallthrough;
-	case -1:
-		fw_load_abort(fw_sysfs);
-		break;
-	}
-out:
-	mutex_unlock(&fw_lock);
-	return written;
-}
-
-static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
-
-static void firmware_rw_data(struct fw_priv *fw_priv, char *buffer,
-			   loff_t offset, size_t count, bool read)
-{
-	if (read)
-		memcpy(buffer, fw_priv->data + offset, count);
-	else
-		memcpy(fw_priv->data + offset, buffer, count);
-}
-
-static void firmware_rw(struct fw_priv *fw_priv, char *buffer,
-			loff_t offset, size_t count, bool read)
-{
-	while (count) {
-		void *page_data;
-		int page_nr = offset >> PAGE_SHIFT;
-		int page_ofs = offset & (PAGE_SIZE-1);
-		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
-
-		page_data = kmap(fw_priv->pages[page_nr]);
-
-		if (read)
-			memcpy(buffer, page_data + page_ofs, page_cnt);
-		else
-			memcpy(page_data + page_ofs, buffer, page_cnt);
-
-		kunmap(fw_priv->pages[page_nr]);
-		buffer += page_cnt;
-		offset += page_cnt;
-		count -= page_cnt;
-	}
-}
-
-static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
-				  struct bin_attribute *bin_attr,
-				  char *buffer, loff_t offset, size_t count)
-{
-	struct device *dev = kobj_to_dev(kobj);
-	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
-	struct fw_priv *fw_priv;
-	ssize_t ret_count;
-
-	mutex_lock(&fw_lock);
-	fw_priv = fw_sysfs->fw_priv;
-	if (!fw_priv || fw_sysfs_done(fw_priv)) {
-		ret_count = -ENODEV;
-		goto out;
-	}
-	if (offset > fw_priv->size) {
-		ret_count = 0;
-		goto out;
-	}
-	if (count > fw_priv->size - offset)
-		count = fw_priv->size - offset;
-
-	ret_count = count;
-
-	if (fw_priv->data)
-		firmware_rw_data(fw_priv, buffer, offset, count, true);
-	else
-		firmware_rw(fw_priv, buffer, offset, count, true);
-
-out:
-	mutex_unlock(&fw_lock);
-	return ret_count;
-}
-
-static int fw_realloc_pages(struct fw_sysfs *fw_sysfs, int min_size)
-{
-	int err;
-
-	err = fw_grow_paged_buf(fw_sysfs->fw_priv,
-				PAGE_ALIGN(min_size) >> PAGE_SHIFT);
-	if (err)
-		fw_load_abort(fw_sysfs);
-	return err;
-}
-
-/**
- * firmware_data_write() - write method for firmware
- * @filp: open sysfs file
- * @kobj: kobject for the device
- * @bin_attr: bin_attr structure
- * @buffer: buffer being written
- * @offset: buffer offset for write in total data store area
- * @count: buffer size
- *
- *	Data written to the 'data' attribute will be later handed to
- *	the driver as a firmware image.
- **/
-static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
-				   struct bin_attribute *bin_attr,
-				   char *buffer, loff_t offset, size_t count)
-{
-	struct device *dev = kobj_to_dev(kobj);
-	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
-	struct fw_priv *fw_priv;
-	ssize_t retval;
-
-	if (!capable(CAP_SYS_RAWIO))
-		return -EPERM;
-
-	mutex_lock(&fw_lock);
-	fw_priv = fw_sysfs->fw_priv;
-	if (!fw_priv || fw_sysfs_done(fw_priv)) {
-		retval = -ENODEV;
-		goto out;
-	}
-
-	if (fw_priv->data) {
-		if (offset + count > fw_priv->allocated_size) {
-			retval = -ENOMEM;
-			goto out;
-		}
-		firmware_rw_data(fw_priv, buffer, offset, count, false);
-		retval = count;
-	} else {
-		retval = fw_realloc_pages(fw_sysfs, offset + count);
-		if (retval)
-			goto out;
-
-		retval = count;
-		firmware_rw(fw_priv, buffer, offset, count, false);
-	}
-
-	fw_priv->size = max_t(size_t, offset + count, fw_priv->size);
-out:
-	mutex_unlock(&fw_lock);
-	return retval;
-}
-
-static struct bin_attribute firmware_attr_data = {
-	.attr = { .name = "data", .mode = 0644 },
-	.size = 0,
-	.read = firmware_data_read,
-	.write = firmware_data_write,
-};
-
-static struct attribute *fw_dev_attrs[] = {
-	&dev_attr_loading.attr,
-	NULL
-};
-
-static struct bin_attribute *fw_dev_bin_attrs[] = {
-	&firmware_attr_data,
-	NULL
-};
-
-static const struct attribute_group fw_dev_attr_group = {
-	.attrs = fw_dev_attrs,
-	.bin_attrs = fw_dev_bin_attrs,
-};
-
-static const struct attribute_group *fw_dev_attr_groups[] = {
-	&fw_dev_attr_group,
-	NULL
-};
-
-static struct fw_sysfs *
-fw_create_instance(struct firmware *firmware, const char *fw_name,
-		   struct device *device, u32 opt_flags)
-{
-	struct fw_sysfs *fw_sysfs;
-	struct device *f_dev;
-
-	fw_sysfs = kzalloc(sizeof(*fw_sysfs), GFP_KERNEL);
-	if (!fw_sysfs) {
-		fw_sysfs = ERR_PTR(-ENOMEM);
-		goto exit;
-	}
-
-	fw_sysfs->nowait = !!(opt_flags & FW_OPT_NOWAIT);
-	fw_sysfs->fw = firmware;
-	f_dev = &fw_sysfs->dev;
-
-	device_initialize(f_dev);
-	dev_set_name(f_dev, "%s", fw_name);
-	f_dev->parent = device;
-	f_dev->class = &firmware_class;
-	f_dev->groups = fw_dev_attr_groups;
-exit:
-	return fw_sysfs;
 }
 
 /**

drivers/base/firmware_loader/fallback.h

···
 #include <linux/device.h>
 
 #include "firmware.h"
-
-/**
- * struct firmware_fallback_config - firmware fallback configuration settings
- *
- * Helps describe and fine tune the fallback mechanism.
- *
- * @force_sysfs_fallback: force the sysfs fallback mechanism to be used
- * 	as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y.
- * 	Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
- * 	functionality on a kernel where that config entry has been disabled.
- * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism.
- * 	This emulates the behaviour as if we had set the kernel
- * 	config CONFIG_FW_LOADER_USER_HELPER=n.
- * @old_timeout: for internal use
- * @loading_timeout: the timeout to wait for the fallback mechanism before
- * 	giving up, in seconds.
- */
-struct firmware_fallback_config {
-	unsigned int force_sysfs_fallback;
-	unsigned int ignore_sysfs_fallback;
-	int old_timeout;
-	int loading_timeout;
-};
+#include "sysfs.h"
 
 #ifdef CONFIG_FW_LOADER_USER_HELPER
 int firmware_fallback_sysfs(struct firmware *fw, const char *name,
···
 
 void fw_fallback_set_cache_timeout(void);
 void fw_fallback_set_default_timeout(void);
-
-int register_sysfs_loader(void);
-void unregister_sysfs_loader(void);
-#ifdef CONFIG_SYSCTL
-extern int register_firmware_config_sysctl(void);
-extern void unregister_firmware_config_sysctl(void);
-#else
-static inline int register_firmware_config_sysctl(void)
-{
-	return 0;
-}
-static inline void unregister_firmware_config_sysctl(void) { }
-#endif /* CONFIG_SYSCTL */
 
 #else /* CONFIG_FW_LOADER_USER_HELPER */
 static inline int firmware_fallback_sysfs(struct firmware *fw, const char *name,
···
 static inline void kill_pending_fw_fallback_reqs(bool only_kill_custom) { }
 static inline void fw_fallback_set_cache_timeout(void) { }
 static inline void fw_fallback_set_default_timeout(void) { }
-
-static inline int register_sysfs_loader(void)
-{
-	return 0;
-}
-
-static inline void unregister_sysfs_loader(void)
-{
-}
 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 
 #ifdef CONFIG_EFI_EMBEDDED_FIRMWARE

drivers/base/firmware_loader/firmware.h

···
 };
 
 extern struct mutex fw_lock;
+extern struct firmware_cache fw_cache;
 
 static inline bool __fw_state_check(struct fw_priv *fw_priv,
 				    enum fw_status status)
···
 	__fw_state_set(fw_priv, FW_STATUS_DONE);
 }
 
+static inline bool fw_state_is_done(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_DONE);
+}
+
+static inline bool fw_state_is_loading(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_LOADING);
+}
+
+int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
+			 struct fw_priv **fw_priv, void *dbuf, size_t size,
+			 size_t offset, u32 opt_flags);
 int assign_fw(struct firmware *fw, struct device *device);
+void free_fw_priv(struct fw_priv *fw_priv);
+void fw_state_init(struct fw_priv *fw_priv);
 
 #ifdef CONFIG_FW_LOADER
 bool firmware_is_builtin(const struct firmware *fw);

drivers/base/firmware_loader/main.c

···
 #include <linux/syscore_ops.h>
 #include <linux/reboot.h>
 #include <linux/security.h>
+#include <linux/zstd.h>
 #include <linux/xz.h>
 
 #include <generated/utsrelease.h>
···
  * guarding for corner cases a global lock should be OK */
 DEFINE_MUTEX(fw_lock);
 
-static struct firmware_cache fw_cache;
+struct firmware_cache fw_cache;
 
-static void fw_state_init(struct fw_priv *fw_priv)
+void fw_state_init(struct fw_priv *fw_priv)
 {
 	struct fw_state *fw_st = &fw_priv->fw_st;
 
···
 }
 
 /* Returns 1 for batching firmware requests with the same name */
-static int alloc_lookup_fw_priv(const char *fw_name,
-				struct firmware_cache *fwc,
-				struct fw_priv **fw_priv,
-				void *dbuf,
-				size_t size,
-				size_t offset,
-				u32 opt_flags)
+int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
+			 struct fw_priv **fw_priv, void *dbuf, size_t size,
+			 size_t offset, u32 opt_flags)
 {
 	struct fw_priv *tmp;
 
···
 	kfree(fw_priv);
 }
 
-static void free_fw_priv(struct fw_priv *fw_priv)
+void free_fw_priv(struct fw_priv *fw_priv)
 {
 	struct firmware_cache *fwc = fw_priv->fwc;
 	spin_lock(&fwc->lock);
···
 	fw_priv->pages = NULL;
 	fw_priv->page_array_size = 0;
 	fw_priv->nr_pages = 0;
+	fw_priv->data = NULL;
+	fw_priv->size = 0;
 }
 
 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
···
 #endif
 
 /*
+ * ZSTD-compressed firmware support
+ */
+#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
+static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,
+			      size_t in_size, const void *in_buffer)
+{
+	size_t len, out_size, workspace_size;
+	void *workspace, *out_buf;
+	zstd_dctx *ctx;
+	int err;
+
+	if (fw_priv->allocated_size) {
+		out_size = fw_priv->allocated_size;
+		out_buf = fw_priv->data;
+	} else {
+		zstd_frame_header params;
+
+		if (zstd_get_frame_header(&params, in_buffer, in_size) ||
+		    params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
+			dev_dbg(dev, "%s: invalid zstd header\n", __func__);
+			return -EINVAL;
+		}
+		out_size = params.frameContentSize;
+		out_buf = vzalloc(out_size);
+		if (!out_buf)
+			return -ENOMEM;
+	}
+
+	workspace_size = zstd_dctx_workspace_bound();
+	workspace = kvzalloc(workspace_size, GFP_KERNEL);
+	if (!workspace) {
+		err = -ENOMEM;
+		goto error;
+	}
+
+	ctx = zstd_init_dctx(workspace, workspace_size);
+	if (!ctx) {
+		dev_dbg(dev, "%s: failed to initialize context\n", __func__);
+		err = -EINVAL;
+		goto error;
+	}
+
+	len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);
+	if (zstd_is_error(len)) {
+		dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,
+			zstd_get_error_code(len));
+		err = -EINVAL;
+		goto error;
+	}
+
+	if (!fw_priv->allocated_size)
+		fw_priv->data = out_buf;
+	fw_priv->size = len;
+	err = 0;
+
+ error:
+	kvfree(workspace);
+	if (err && !fw_priv->allocated_size)
+		vfree(out_buf);
+	return err;
+}
+#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */
+
+/*
  * XZ-compressed firmware support
  */
-#ifdef CONFIG_FW_LOADER_COMPRESS
+#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
 /* show an error and return the standard error code */
 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
 {
···
 	else
 		return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
 }
-#endif /* CONFIG_FW_LOADER_COMPRESS */
+#endif /* CONFIG_FW_LOADER_COMPRESS_XZ */
 
 /* direct firmware loading support */
 static char fw_path_para[256];
···
 	if (!(opt_flags & FW_OPT_PARTIAL))
 		nondirect = true;
 
-#ifdef CONFIG_FW_LOADER_COMPRESS
+#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
+	if (ret == -ENOENT && nondirect)
+		ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
+						 fw_decompress_zstd);
+#endif
+#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
 	if (ret == -ENOENT && nondirect)
 		ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 						 fw_decompress_xz);

drivers/base/firmware_loader/sysfs.c

···
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/highmem.h>
+#include <linux/module.h>
+#include <linux/security.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "sysfs.h"
+
+/*
+ * sysfs support for firmware loader
+ */
+
+void __fw_load_abort(struct fw_priv *fw_priv)
+{
+	/*
+	 * There is a small window in which user can write to 'loading'
+	 * between loading done/aborted and disappearance of 'loading'
+	 */
+	if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv))
+		return;
+
+	fw_state_aborted(fw_priv);
+}
+
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
+			    char *buf)
+{
+	return sysfs_emit(buf, "%d\n", __firmware_loading_timeout());
+}
+
+/**
+ * timeout_store() - set number of seconds to wait for firmware
+ * @class: device class pointer
+ * @attr: device attribute pointer
+ * @buf: buffer to scan for timeout value
+ * @count: number of bytes in @buf
+ *
+ *	Sets the number of seconds to wait for the firmware.  Once
+ *	this expires an error will be returned to the driver and no
+ *	firmware will be provided.
+ *
+ *	Note: zero means 'wait forever'.
+ **/
+static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
+			     const char *buf, size_t count)
+{
+	int tmp_loading_timeout = simple_strtol(buf, NULL, 10);
+
+	if (tmp_loading_timeout < 0)
+		tmp_loading_timeout = 0;
+
+	__fw_fallback_set_timeout(tmp_loading_timeout);
+
+	return count;
+}
+static CLASS_ATTR_RW(timeout);
+
+static struct attribute *firmware_class_attrs[] = {
+	&class_attr_timeout.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(firmware_class);
+
+static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env)
+{
+	if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name))
+		return -ENOMEM;
+	if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout()))
+		return -ENOMEM;
+	if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	int err = 0;
+
+	mutex_lock(&fw_lock);
+	if (fw_sysfs->fw_priv)
+		err = do_firmware_uevent(fw_sysfs, env);
+	mutex_unlock(&fw_lock);
+	return err;
+}
+#endif /* CONFIG_FW_LOADER_USER_HELPER */
+
+static void fw_dev_release(struct device *dev)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+
+	if (fw_sysfs->fw_upload_priv) {
+		free_fw_priv(fw_sysfs->fw_priv);
+		kfree(fw_sysfs->fw_upload_priv);
+	}
+	kfree(fw_sysfs);
+}
+
+static struct class firmware_class = {
+	.name		= "firmware",
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+	.class_groups	= firmware_class_groups,
+	.dev_uevent	= firmware_uevent,
+#endif
+	.dev_release	= fw_dev_release,
+};
+
+int register_sysfs_loader(void)
+{
+	int ret = class_register(&firmware_class);
+
+	if (ret != 0)
+		return ret;
+	return register_firmware_config_sysctl();
+}
+
+void unregister_sysfs_loader(void)
+{
+	unregister_firmware_config_sysctl();
+	class_unregister(&firmware_class);
+}
+
+static ssize_t firmware_loading_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	int loading = 0;
+
+	mutex_lock(&fw_lock);
+	if (fw_sysfs->fw_priv)
+		loading = fw_state_is_loading(fw_sysfs->fw_priv);
+	mutex_unlock(&fw_lock);
+
+	return sysfs_emit(buf, "%d\n", loading);
+}
+
+/**
+ * firmware_loading_store() - set value in the 'loading' control file
+ * @dev: device pointer
+ * @attr: device attribute pointer
+ * @buf: buffer to scan for loading control value
+ * @count: number of bytes in @buf
+ *
+ *	The relevant values are:
+ *
+ *	 1: Start a load, discarding any previous partial load.
+ *	 0: Conclude the load and hand the data to the driver code.
+ *	-1: Conclude the load with an error and discard any written data.
+ **/
+static ssize_t firmware_loading_store(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	struct fw_priv *fw_priv;
+	ssize_t written = count;
+	int loading = simple_strtol(buf, NULL, 10);
+
+	mutex_lock(&fw_lock);
+	fw_priv = fw_sysfs->fw_priv;
+	if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv))
+		goto out;
+
+	switch (loading) {
+	case 1:
+		/* discarding any previous partial load */
+		fw_free_paged_buf(fw_priv);
+		fw_state_start(fw_priv);
+		break;
+	case 0:
+		if (fw_state_is_loading(fw_priv)) {
+			int rc;
+
+			/*
+			 * Several loading requests may be pending on
+			 * one same firmware buf, so let all requests
+			 * see the mapped 'buf->data' once the loading
+			 * is completed.
+			 */
+			rc = fw_map_paged_buf(fw_priv);
+			if (rc)
+				dev_err(dev, "%s: map pages failed\n",
+					__func__);
+			else
+				rc = security_kernel_post_load_data(fw_priv->data,
+								    fw_priv->size,
+								    LOADING_FIRMWARE,
+								    "blob");
+
+			/*
+			 * Same logic as fw_load_abort, only the DONE bit
+			 * is ignored and we set ABORT only on failure.
+			 */
+			if (rc) {
+				fw_state_aborted(fw_priv);
+				written = rc;
+			} else {
+				fw_state_done(fw_priv);
+
+				/*
+				 * If this is a user-initiated firmware upload
+				 * then start the upload in a worker thread now.
+				 */
+				rc = fw_upload_start(fw_sysfs);
+				if (rc)
+					written = rc;
+			}
+			break;
+		}
+		fallthrough;
+	default:
+		dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
+		fallthrough;
+	case -1:
+		fw_load_abort(fw_sysfs);
+		if (fw_sysfs->fw_upload_priv)
+			fw_state_init(fw_sysfs->fw_priv);
+
+		break;
+	}
+out:
+	mutex_unlock(&fw_lock);
+	return written;
+}
+
+DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
+
+static void firmware_rw_data(struct fw_priv *fw_priv, char *buffer,
+			     loff_t offset, size_t count, bool read)
+{
+	if (read)
+		memcpy(buffer, fw_priv->data + offset, count);
+	else
+		memcpy(fw_priv->data + offset, buffer, count);
+}
+
+static void firmware_rw(struct fw_priv *fw_priv, char *buffer,
+			loff_t offset, size_t count, bool read)
+{
+	while (count) {
+		void *page_data;
+		int page_nr = offset >> PAGE_SHIFT;
+		int page_ofs = offset & (PAGE_SIZE - 1);
+		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
+
+		page_data = kmap(fw_priv->pages[page_nr]);
+
+		if (read)
+			memcpy(buffer, page_data + page_ofs, page_cnt);
+		else
+			memcpy(page_data + page_ofs, buffer, page_cnt);
+
+		kunmap(fw_priv->pages[page_nr]);
+		buffer += page_cnt;
+		offset += page_cnt;
+		count -= page_cnt;
+	}
+}
+
+static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
+				  struct bin_attribute *bin_attr,
+				  char *buffer, loff_t offset, size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	struct fw_priv *fw_priv;
+	ssize_t ret_count;
+
+	mutex_lock(&fw_lock);
+	fw_priv = fw_sysfs->fw_priv;
+	if (!fw_priv || fw_state_is_done(fw_priv)) {
+		ret_count = -ENODEV;
+		goto out;
+	}
+	if (offset > fw_priv->size) {
+		ret_count = 0;
+		goto out;
+	}
+	if (count > fw_priv->size - offset)
+		count = fw_priv->size - offset;
+
+	ret_count = count;
+
+	if (fw_priv->data)
+		firmware_rw_data(fw_priv, buffer, offset, count, true);
+	else
+		firmware_rw(fw_priv, buffer, offset, count, true);
+
+out:
+	mutex_unlock(&fw_lock);
+	return ret_count;
+}
+
+static int fw_realloc_pages(struct fw_sysfs *fw_sysfs, int min_size)
+{
+	int err;
+
+	err = fw_grow_paged_buf(fw_sysfs->fw_priv,
+				PAGE_ALIGN(min_size) >> PAGE_SHIFT);
+	if (err)
+		fw_load_abort(fw_sysfs);
+	return err;
+}
+
+/**
+ * firmware_data_write() - write method for firmware
+ * @filp: open sysfs file
+ * @kobj: kobject for the device
+ * @bin_attr: bin_attr structure
+ * @buffer: buffer being written
+ * @offset: buffer offset for write in total data store area
+ * @count: buffer size
+ *
+ *	Data written to the 'data' attribute will be later handed to
+ *	the driver as a firmware image.
+ **/
+static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
+				   struct bin_attribute *bin_attr,
+				   char *buffer, loff_t offset, size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
+	struct fw_priv *fw_priv;
+	ssize_t retval;
+
+	if (!capable(CAP_SYS_RAWIO))
+		return -EPERM;
+
+	mutex_lock(&fw_lock);
+	fw_priv = fw_sysfs->fw_priv;
+	if (!fw_priv || fw_state_is_done(fw_priv)) {
+		retval = -ENODEV;
+		goto out;
+	}
+
+	if (fw_priv->data) {
+		if (offset + count > fw_priv->allocated_size) {
+			retval = -ENOMEM;
+			goto out;
+		}
+		firmware_rw_data(fw_priv, buffer, offset, count, false);
+		retval = count;
+	} else {
+		retval = fw_realloc_pages(fw_sysfs, offset + count);
+		if (retval)
+			goto out;
+
+		retval = count;
+		firmware_rw(fw_priv, buffer, offset, count, false);
+	}
+
+	fw_priv->size = max_t(size_t, offset + count, fw_priv->size);
+out:
+	mutex_unlock(&fw_lock);
+	return retval;
+}
+
+static struct bin_attribute firmware_attr_data = {
+	.attr = { .name = "data", .mode = 0644 },
+	.size = 0,
+	.read = firmware_data_read,
+	.write = firmware_data_write,
+};
+
+static struct attribute *fw_dev_attrs[] = {
+	&dev_attr_loading.attr,
+#ifdef CONFIG_FW_UPLOAD
+	&dev_attr_cancel.attr,
+	&dev_attr_status.attr,
+	&dev_attr_error.attr,
+	&dev_attr_remaining_size.attr,
+#endif
+	NULL
+};
+
+static struct bin_attribute *fw_dev_bin_attrs[] = {
+	&firmware_attr_data,
+	NULL
+};
+
+static const struct attribute_group fw_dev_attr_group = {
+	.attrs = fw_dev_attrs,
+	.bin_attrs = fw_dev_bin_attrs,
+#ifdef CONFIG_FW_UPLOAD
+	.is_visible = fw_upload_is_visible,
+#endif
+};
+
+static const struct attribute_group *fw_dev_attr_groups[] = {
+	&fw_dev_attr_group,
+	NULL
+};
+
+struct fw_sysfs *
+fw_create_instance(struct firmware *firmware, const char *fw_name,
+		   struct device *device, u32 opt_flags)
+{
+	struct fw_sysfs *fw_sysfs;
+	struct device *f_dev;
+
+	fw_sysfs = kzalloc(sizeof(*fw_sysfs), GFP_KERNEL);
+	if (!fw_sysfs) {
+		fw_sysfs = ERR_PTR(-ENOMEM);
+		goto exit;
+	}
+
+	fw_sysfs->nowait = !!(opt_flags & FW_OPT_NOWAIT);
+	fw_sysfs->fw = firmware;
+	f_dev = &fw_sysfs->dev;
+
+	device_initialize(f_dev);
+	dev_set_name(f_dev, "%s", fw_name);
+	f_dev->parent = device;
+	f_dev->class = &firmware_class;
+	f_dev->groups = fw_dev_attr_groups;
+exit:
+	return fw_sysfs;
+}

drivers/base/firmware_loader/sysfs.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __FIRMWARE_SYSFS_H
+#define __FIRMWARE_SYSFS_H
+
+#include <linux/device.h>
+
+#include "firmware.h"
+
+MODULE_IMPORT_NS(FIRMWARE_LOADER_PRIVATE);
+
+extern struct firmware_fallback_config fw_fallback_config;
+extern struct device_attribute dev_attr_loading;
+
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+/**
+ * struct firmware_fallback_config - firmware fallback configuration settings
+ *
+ * Helps describe and fine tune the fallback mechanism.
+ *
+ * @force_sysfs_fallback: force the sysfs fallback mechanism to be used
+ *	as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y.
+ *	Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
+ *	functionality on a kernel where that config entry has been disabled.
+ * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism.
+ *	This emulates the behaviour as if we had set the kernel
+ *	config CONFIG_FW_LOADER_USER_HELPER=n.
+ * @old_timeout: for internal use
+ * @loading_timeout: the timeout to wait for the fallback mechanism before
+ *	giving up, in seconds.
+ */
+struct firmware_fallback_config {
+	unsigned int force_sysfs_fallback;
+	unsigned int ignore_sysfs_fallback;
+	int old_timeout;
+	int loading_timeout;
+};
+
+/* These getters are vetted to use int properly */
+static inline int __firmware_loading_timeout(void)
+{
+	return fw_fallback_config.loading_timeout;
+}
+
+/* These setters are vetted to use int properly */
+static inline void __fw_fallback_set_timeout(int timeout)
+{
+	fw_fallback_config.loading_timeout = timeout;
+}
+#endif
+
+#ifdef CONFIG_FW_LOADER_SYSFS
+int register_sysfs_loader(void);
+void unregister_sysfs_loader(void);
+#if defined(CONFIG_FW_LOADER_USER_HELPER) && defined(CONFIG_SYSCTL)
+int register_firmware_config_sysctl(void);
+void unregister_firmware_config_sysctl(void);
+#else
+static inline int register_firmware_config_sysctl(void)
+{
+	return 0;
+}
+
+static inline void unregister_firmware_config_sysctl(void) { }
+#endif /* CONFIG_FW_LOADER_USER_HELPER && CONFIG_SYSCTL */
+#else /* CONFIG_FW_LOADER_SYSFS */
+static inline int register_sysfs_loader(void)
+{
+	return 0;
+}
+
+static inline void unregister_sysfs_loader(void)
+{
+}
+#endif /* CONFIG_FW_LOADER_SYSFS */
+
+struct fw_sysfs {
+	bool nowait;
+	struct device dev;
+	struct fw_priv *fw_priv;
+	struct firmware *fw;
+	void *fw_upload_priv;
+};
+
+static inline struct fw_sysfs *to_fw_sysfs(struct device *dev)
+{
+	return container_of(dev, struct fw_sysfs, dev);
+}
+
+void __fw_load_abort(struct fw_priv *fw_priv);
+
+static inline void fw_load_abort(struct fw_sysfs *fw_sysfs)
+{
+	struct fw_priv *fw_priv = fw_sysfs->fw_priv;
+
+	__fw_load_abort(fw_priv);
+}
+
+struct fw_sysfs *
+fw_create_instance(struct firmware *firmware, const char *fw_name,
+		   struct device *device, u32 opt_flags);
+
+#ifdef CONFIG_FW_UPLOAD
+extern struct device_attribute dev_attr_status;
+extern struct device_attribute dev_attr_error;
+extern struct device_attribute dev_attr_cancel;
+extern struct device_attribute dev_attr_remaining_size;
+
+int fw_upload_start(struct fw_sysfs *fw_sysfs);
+umode_t fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n);
+#else
+static inline int fw_upload_start(struct fw_sysfs *fw_sysfs)
+{
+	return 0;
+}
+#endif
+
+#endif /* __FIRMWARE_SYSFS_H */

drivers/base/firmware_loader/sysfs_upload.c

···
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "sysfs_upload.h"
+
+/*
+ * Support for user-space to initiate a firmware upload to a device.
+ */
+
+static const char * const fw_upload_prog_str[] = {
+	[FW_UPLOAD_PROG_IDLE]	      = "idle",
+	[FW_UPLOAD_PROG_RECEIVING]    = "receiving",
+	[FW_UPLOAD_PROG_PREPARING]    = "preparing",
+	[FW_UPLOAD_PROG_TRANSFERRING] = "transferring",
+	[FW_UPLOAD_PROG_PROGRAMMING]  = "programming"
+};
+
+static const char * const fw_upload_err_str[] = {
+	[FW_UPLOAD_ERR_NONE]	     = "none",
+	[FW_UPLOAD_ERR_HW_ERROR]     = "hw-error",
+	[FW_UPLOAD_ERR_TIMEOUT]	     = "timeout",
+	[FW_UPLOAD_ERR_CANCELED]     = "user-abort",
+	[FW_UPLOAD_ERR_BUSY]	     = "device-busy",
+	[FW_UPLOAD_ERR_INVALID_SIZE] = "invalid-file-size",
+	[FW_UPLOAD_ERR_RW_ERROR]     = "read-write-error",
+	[FW_UPLOAD_ERR_WEAROUT]	     = "flash-wearout",
+};
+
+static const char *fw_upload_progress(struct device *dev,
+				      enum fw_upload_prog prog)
+{
+	const char *status = "unknown-status";
+
+	if (prog < FW_UPLOAD_PROG_MAX)
+		status = fw_upload_prog_str[prog];
+	else
+		dev_err(dev, "Invalid status during secure update: %d\n", prog);
+
+	return status;
+}
+
+static const char *fw_upload_error(struct device *dev,
+				   enum fw_upload_err err_code)
+{
+	const char *error = "unknown-error";
+
+	if (err_code < FW_UPLOAD_ERR_MAX)
+		error = fw_upload_err_str[err_code];
+	else
+		dev_err(dev, "Invalid error code during secure update: %d\n",
+			err_code);
+
+	return error;
+}
+
+static ssize_t
+status_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
+
+	return sysfs_emit(buf, "%s\n", fw_upload_progress(dev, fwlp->progress));
+}
+DEVICE_ATTR_RO(status);
+
+static ssize_t
+error_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
+	int ret;
+
+	mutex_lock(&fwlp->lock);
+
+	if (fwlp->progress != FW_UPLOAD_PROG_IDLE)
+		ret = -EBUSY;
+	else if (!fwlp->err_code)
+		ret = 0;
+	else
+		ret = sysfs_emit(buf, "%s:%s\n",
+				 fw_upload_progress(dev, fwlp->err_progress),
+				 fw_upload_error(dev, fwlp->err_code));
+
+	mutex_unlock(&fwlp->lock);
+
+	return ret;
+}
+DEVICE_ATTR_RO(error);
+
+static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
+{
+	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
+	int ret = count;
+	bool cancel;
+
+	if (kstrtobool(buf, &cancel) || !cancel)
+		return -EINVAL;
+
+	mutex_lock(&fwlp->lock);
+	if (fwlp->progress == FW_UPLOAD_PROG_IDLE)
+		ret = -ENODEV;
+
+	fwlp->ops->cancel(fwlp->fw_upload);
+	mutex_unlock(&fwlp->lock);
+
+	return ret;
+}
+DEVICE_ATTR_WO(cancel);
+
+static ssize_t remaining_size_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
+
+	return sysfs_emit(buf, "%u\n", fwlp->remaining_size);
+}
+DEVICE_ATTR_RO(remaining_size);
+
+umode_t
+fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n)
+{
+	static struct fw_sysfs *fw_sysfs;
+
+	fw_sysfs = to_fw_sysfs(kobj_to_dev(kobj));
+
+	if (fw_sysfs->fw_upload_priv || attr == &dev_attr_loading.attr)
+		return attr->mode;
+
+	return 0;
+}
+
+static void fw_upload_update_progress(struct fw_upload_priv *fwlp,
+				      enum fw_upload_prog new_progress)
+{
+	mutex_lock(&fwlp->lock);
+	fwlp->progress = new_progress;
+	mutex_unlock(&fwlp->lock);
+}
+
+static void fw_upload_set_error(struct fw_upload_priv *fwlp,
+				enum fw_upload_err err_code)
+{
+	mutex_lock(&fwlp->lock);
+	fwlp->err_progress = fwlp->progress;
+	fwlp->err_code = err_code;
+	mutex_unlock(&fwlp->lock);
+}
+
+static void fw_upload_prog_complete(struct fw_upload_priv *fwlp)
+{
+	mutex_lock(&fwlp->lock);
+	fwlp->progress = FW_UPLOAD_PROG_IDLE;
+	mutex_unlock(&fwlp->lock);
+}
+
+static void fw_upload_main(struct work_struct *work)
+{
+	struct fw_upload_priv *fwlp;
+	struct fw_sysfs *fw_sysfs;
+	u32 written = 0, offset = 0;
+	enum fw_upload_err ret;
+	struct device *fw_dev;
+	struct fw_upload *fwl;
+
+	fwlp = container_of(work, struct fw_upload_priv, work);
+	fwl = fwlp->fw_upload;
+	fw_sysfs = (struct fw_sysfs *)fwl->priv;
+	fw_dev = &fw_sysfs->dev;
+
+	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PREPARING);
+	ret = fwlp->ops->prepare(fwl, fwlp->data, fwlp->remaining_size);
+	if (ret != FW_UPLOAD_ERR_NONE) {
+		fw_upload_set_error(fwlp, ret);
+		goto putdev_exit;
+	}
+
+	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_TRANSFERRING);
+	while (fwlp->remaining_size) {
+		ret = fwlp->ops->write(fwl, fwlp->data, offset,
+					fwlp->remaining_size, &written);
+		if (ret != FW_UPLOAD_ERR_NONE || !written) {
+			if (ret == FW_UPLOAD_ERR_NONE) {
+				dev_warn(fw_dev, "write-op wrote zero data\n");
+				ret = FW_UPLOAD_ERR_RW_ERROR;
+			}
+			fw_upload_set_error(fwlp, ret);
+			goto done;
+		}
+
+		fwlp->remaining_size -= written;
+		offset += written;
+	}
+
+	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PROGRAMMING);
+	ret = fwlp->ops->poll_complete(fwl);
+	if (ret != FW_UPLOAD_ERR_NONE)
+		fw_upload_set_error(fwlp, ret);
+
+done:
+	if (fwlp->ops->cleanup)
+		fwlp->ops->cleanup(fwl);
+
+putdev_exit:
+	put_device(fw_dev->parent);
+
+	/*
+	 * Note: fwlp->remaining_size is left unmodified here to provide
+	 * additional information on errors. It will be reinitialized when
+	 * the next firmeware upload begins.
+	 */
+	mutex_lock(&fw_lock);
+	fw_free_paged_buf(fw_sysfs->fw_priv);
+	fw_state_init(fw_sysfs->fw_priv);
+	mutex_unlock(&fw_lock);
+	fwlp->data = NULL;
+	fw_upload_prog_complete(fwlp);
+}
+
+/*
+ * Start a worker thread to upload data to the parent driver.
+ * Must be called with fw_lock held.
+ */
+int fw_upload_start(struct fw_sysfs *fw_sysfs)
+{
+	struct fw_priv *fw_priv = fw_sysfs->fw_priv;
+	struct device *fw_dev = &fw_sysfs->dev;
+	struct fw_upload_priv *fwlp;
+
+	if (!fw_sysfs->fw_upload_priv)
+		return 0;
+
+	if (!fw_priv->size) {
+		fw_free_paged_buf(fw_priv);
+		fw_state_init(fw_sysfs->fw_priv);
+		return 0;
+	}
+
+	fwlp = fw_sysfs->fw_upload_priv;
+	mutex_lock(&fwlp->lock);
+
+	/* Do not interfere with an on-going fw_upload */
+	if (fwlp->progress != FW_UPLOAD_PROG_IDLE) {
+		mutex_unlock(&fwlp->lock);
+		return -EBUSY;
+	}
+
+	get_device(fw_dev->parent); /* released in fw_upload_main */
+
+	fwlp->progress = FW_UPLOAD_PROG_RECEIVING;
+	fwlp->err_code = 0;
+	fwlp->remaining_size = fw_priv->size;
+	fwlp->data = fw_priv->data;
+
+	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
+		 __func__, fw_priv->fw_name,
+		 fw_priv, fw_priv->data,
+		 (unsigned int)fw_priv->size);
+
+	queue_work(system_long_wq, &fwlp->work);
+	mutex_unlock(&fwlp->lock);
+
+	return 0;
+}
+
+/**
+ * firmware_upload_register() - register for the firmware upload sysfs API
+ * @module: kernel module of this device
+ * @parent: parent device instantiating firmware upload
+ * @name: firmware name to be associated with this device
+ * @ops: pointer to structure of firmware upload ops
+ * @dd_handle: pointer to parent driver private data
+ *
+ *	@name must be unique among all users of firmware upload. The firmware
+ *	sysfs files for this device will be found at /sys/class/firmware/@name.
+ *
+ *	Return: struct fw_upload pointer or ERR_PTR()
+ *
+ **/
+struct fw_upload *
+firmware_upload_register(struct module *module, struct device *parent,
+			 const char *name, const struct fw_upload_ops *ops,
+			 void *dd_handle)
+{
+	u32 opt_flags = FW_OPT_NOCACHE;
+	struct fw_upload *fw_upload;
+	struct fw_upload_priv *fw_upload_priv;
+	struct fw_sysfs *fw_sysfs;
+	struct fw_priv *fw_priv;
+	struct device *fw_dev;
+	int ret;
+
+	if (!name || name[0] == '\0')
+		return ERR_PTR(-EINVAL);
+
+	if (!ops || !ops->cancel || !ops->prepare ||
+	    !ops->write || !ops->poll_complete) {
+		dev_err(parent, "Attempt to register without all required ops\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (!try_module_get(module))
+		return ERR_PTR(-EFAULT);
+
+	fw_upload = kzalloc(sizeof(*fw_upload), GFP_KERNEL);
+	if (!fw_upload) {
+		ret = -ENOMEM;
+		goto exit_module_put;
+	}
+
+	fw_upload_priv = kzalloc(sizeof(*fw_upload_priv), GFP_KERNEL);
+	if (!fw_upload_priv) {
+		ret = -ENOMEM;
+		goto free_fw_upload;
+	}
+
+	fw_upload_priv->fw_upload = fw_upload;
+	fw_upload_priv->ops = ops;
+	mutex_init(&fw_upload_priv->lock);
+	fw_upload_priv->module = module;
+	fw_upload_priv->name = name;
+	fw_upload_priv->err_code = 0;
+	fw_upload_priv->progress = FW_UPLOAD_PROG_IDLE;
+	INIT_WORK(&fw_upload_priv->work, fw_upload_main);
+	fw_upload->dd_handle = dd_handle;
+
+	fw_sysfs = fw_create_instance(NULL, name, parent, opt_flags);
+	if (IS_ERR(fw_sysfs)) {
+		ret = PTR_ERR(fw_sysfs);
+		goto free_fw_upload_priv;
+	}
+	fw_upload->priv = fw_sysfs;
+	fw_sysfs->fw_upload_priv = fw_upload_priv;
+	fw_dev = &fw_sysfs->dev;
+
+	ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv,  NULL, 0, 0,
+				   FW_OPT_NOCACHE);
+	if (ret != 0) {
+		if (ret > 0)
+			ret = -EINVAL;
+		goto free_fw_sysfs;
+	}
+	fw_priv->is_paged_buf = true;
+	fw_sysfs->fw_priv = fw_priv;
+
+	ret = device_add(fw_dev);
+	if (ret) {
+		dev_err(fw_dev, "%s: device_register failed\n", __func__);
+		put_device(fw_dev);
+		goto exit_module_put;
+	}
+
+	return fw_upload;
+
+free_fw_sysfs:
+	kfree(fw_sysfs);
+
+free_fw_upload_priv:
+	kfree(fw_upload_priv);
+
+free_fw_upload:
+	kfree(fw_upload);
+
+exit_module_put:
+	module_put(module);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(firmware_upload_register);
+
+/**
+ * firmware_upload_unregister() - Unregister firmware upload interface
+ * @fw_upload: pointer to struct fw_upload
+ **/
+void firmware_upload_unregister(struct fw_upload *fw_upload)
+{
+	struct fw_sysfs *fw_sysfs = fw_upload->priv;
+	struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
+
+	mutex_lock(&fw_upload_priv->lock);
+	if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) {
+		mutex_unlock(&fw_upload_priv->lock);
+		goto unregister;
+	}
+
+	fw_upload_priv->ops->cancel(fw_upload);
+	mutex_unlock(&fw_upload_priv->lock);
+
+	/* Ensure lower-level device-driver is finished */
+	flush_work(&fw_upload_priv->work);
+
+unregister:
+	device_unregister(&fw_sysfs->dev);
+	module_put(fw_upload_priv->module);
+}
+EXPORT_SYMBOL_GPL(firmware_upload_unregister);

drivers/base/firmware_loader/sysfs_upload.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __SYSFS_UPLOAD_H
+#define __SYSFS_UPLOAD_H
+
+#include <linux/device.h>
+
+#include "sysfs.h"
+
+/**
+ * enum fw_upload_prog - firmware upload progress codes
+ * @FW_UPLOAD_PROG_IDLE: there is no firmware upload in progress
+ * @FW_UPLOAD_PROG_RECEIVING: worker thread is receiving firmware data
+ * @FW_UPLOAD_PROG_PREPARING: target device is preparing for firmware upload
+ * @FW_UPLOAD_PROG_TRANSFERRING: data is being copied to the device
+ * @FW_UPLOAD_PROG_PROGRAMMING: device is performing the firmware update
+ * @FW_UPLOAD_PROG_MAX: Maximum progress code marker
+ */
+enum fw_upload_prog {
+	FW_UPLOAD_PROG_IDLE,
+	FW_UPLOAD_PROG_RECEIVING,
+	FW_UPLOAD_PROG_PREPARING,
+	FW_UPLOAD_PROG_TRANSFERRING,
+	FW_UPLOAD_PROG_PROGRAMMING,
+	FW_UPLOAD_PROG_MAX
+};
+
+struct fw_upload_priv {
+	struct fw_upload *fw_upload;
+	struct module *module;
+	const char *name;
+	const struct fw_upload_ops *ops;
+	struct mutex lock;		  /* protect data structure contents */
+	struct work_struct work;
+	const u8 *data;			  /* pointer to update data */
+	u32 remaining_size;		  /* size remaining to transfer */
+	enum fw_upload_prog progress;
+	enum fw_upload_prog err_progress; /* progress at time of failure */
+	enum fw_upload_err err_code;	  /* security manager error code */
+};
+
+#endif /* __SYSFS_UPLOAD_H */

drivers/base/physical_location.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Device physical location support
+ *
+ * Author: Won Chung <[e-mail]>
+ */
+
+#include <linux/acpi.h>
+#include <linux/sysfs.h>
+
+#include "physical_location.h"
+
+bool dev_add_physical_location(struct device *dev)
+{
+	struct acpi_pld_info *pld;
+	acpi_status status;
+
+	if (!has_acpi_companion(dev))
+		return false;
+
+	status = acpi_get_physical_device_location(ACPI_HANDLE(dev), &pld);
+	if (ACPI_FAILURE(status))
+		return false;
+
+	dev->physical_location =
+		kzalloc(sizeof(*dev->physical_location), GFP_KERNEL);
+	if (!dev->physical_location)
+		return false;
+	dev->physical_location->panel = pld->panel;
+	dev->physical_location->vertical_position = pld->vertical_position;
+	dev->physical_location->horizontal_position = pld->horizontal_position;
+	dev->physical_location->dock = pld->dock;
+	dev->physical_location->lid = pld->lid;
+
+	ACPI_FREE(pld);
+	return true;
+}
+
+static ssize_t panel_show(struct device *dev, struct device_attribute *attr,
+	char *buf)
+{
+	const char *panel;
+
+	switch (dev->physical_location->panel) {
+	case DEVICE_PANEL_TOP:
+		panel = "top";
+		break;
+	case DEVICE_PANEL_BOTTOM:
+		panel = "bottom";
+		break;
+	case DEVICE_PANEL_LEFT:
+		panel = "left";
+		break;
+	case DEVICE_PANEL_RIGHT:
+		panel = "right";
+		break;
+	case DEVICE_PANEL_FRONT:
+		panel = "front";
+		break;
+	case DEVICE_PANEL_BACK:
+		panel = "back";
+		break;
+	default:
+		panel = "unknown";
+	}
+	return sysfs_emit(buf, "%s\n", panel);
+}
+static DEVICE_ATTR_RO(panel);
+
+static ssize_t vertical_position_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	const char *vertical_position;
+
+	switch (dev->physical_location->vertical_position) {
+	case DEVICE_VERT_POS_UPPER:
+		vertical_position = "upper";
+		break;
+	case DEVICE_VERT_POS_CENTER:
+		vertical_position = "center";
+		break;
+	case DEVICE_VERT_POS_LOWER:
+		vertical_position = "lower";
+		break;
+	default:
+		vertical_position = "unknown";
+	}
+	return sysfs_emit(buf, "%s\n", vertical_position);
+}
+static DEVICE_ATTR_RO(vertical_position);
+
+static ssize_t horizontal_position_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	const char *horizontal_position;
+
+	switch (dev->physical_location->horizontal_position) {
+	case DEVICE_HORI_POS_LEFT:
+		horizontal_position = "left";
+		break;
+	case DEVICE_HORI_POS_CENTER:
+		horizontal_position = "center";
+		break;
+	case DEVICE_HORI_POS_RIGHT:
+		horizontal_position = "right";
+		break;
+	default:
+		horizontal_position = "unknown";
+	}
+	return sysfs_emit(buf, "%s\n", horizontal_position);
+}
+static DEVICE_ATTR_RO(horizontal_position);
+
+static ssize_t dock_show(struct device *dev, struct device_attribute *attr,
+	char *buf)
+{
+	return sysfs_emit(buf, "%s\n",
+		dev->physical_location->dock ? "yes" : "no");
+}
+static DEVICE_ATTR_RO(dock);
+
+static ssize_t lid_show(struct device *dev, struct device_attribute *attr,
+	char *buf)
+{
+	return sysfs_emit(buf, "%s\n",
+		dev->physical_location->lid ? "yes" : "no");
+}
+static DEVICE_ATTR_RO(lid);
+
+static struct attribute *dev_attr_physical_location[] = {
+	&dev_attr_panel.attr,
+	&dev_attr_vertical_position.attr,
+	&dev_attr_horizontal_position.attr,
+	&dev_attr_dock.attr,
+	&dev_attr_lid.attr,
+	NULL,
+};
+
+const struct attribute_group dev_attr_physical_location_group = {
+	.name = "physical_location",
+	.attrs = dev_attr_physical_location,
+};
+

drivers/base/physical_location.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Device physical location support
+ *
+ * Author: Won Chung <[e-mail]>
+ */
+
+#include <linux/device.h>
+
+#ifdef CONFIG_ACPI
+extern bool dev_add_physical_location(struct device *dev);
+extern const struct attribute_group dev_attr_physical_location_group;
+#else
+static inline bool dev_add_physical_location(struct device *dev) { return false; };
+static const struct attribute_group dev_attr_physical_location_group = {};
+#endif

drivers/base/platform.c

···
 out_not_found:
 	ret = -ENXIO;
 out:
-	WARN(ret == 0, "0 is an invalid IRQ number\n");
+	if (WARN(!ret, "0 is an invalid IRQ number\n"))
+		return -EINVAL;
 	return ret;
 }
 EXPORT_SYMBOL_GPL(platform_get_irq_optional);
···
 
 	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 	if (r) {
-		WARN(r->start == 0, "0 is an invalid IRQ number\n");
+		if (WARN(!r->start, "0 is an invalid IRQ number\n"))
+			return -EINVAL;
 		return r->start;
 	}
 
···
 				     const char *buf, size_t count)
 {
 	struct platform_device *pdev = to_platform_device(dev);
-	char *driver_override, *old, *cp;
+	int ret;
 
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(dev);
-	old = pdev->driver_override;
-	if (strlen(driver_override)) {
-		pdev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		pdev->driver_override = NULL;
-	}
-	device_unlock(dev);
-
-	kfree(old);
+	ret = driver_set_override(dev, &pdev->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/bus/fsl-mc/fsl-mc-bus.c

···
 				     const char *buf, size_t count)
 {
 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
-	char *driver_override, *old = mc_dev->driver_override;
-	char *cp;
+	int ret;
 
 	if (WARN_ON(dev->bus != &fsl_mc_bus_type))
 		return -EINVAL;
 
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	if (strlen(driver_override)) {
-		mc_dev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		mc_dev->driver_override = NULL;
-	}
-
-	kfree(old);
+	ret = driver_set_override(dev, &mc_dev->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/clk/imx/clk-scu.c

···
 		return ERR_PTR(ret);
 	}
 
-	pdev->driver_override = "imx-scu-clk";
+	ret = driver_set_override(&pdev->dev, &pdev->driver_override,
+				  "imx-scu-clk", strlen("imx-scu-clk"));
+	if (ret) {
+		platform_device_put(pdev);
+		return ERR_PTR(ret);
+	}
 
 	ret = imx_clk_scu_attach_pd(&pdev->dev, rsrc_id);
 	if (ret)

drivers/hv/vmbus_drv.c

···
 				     const char *buf, size_t count)
 {
 	struct hv_device *hv_dev = device_to_hv_device(dev);
-	char *driver_override, *old, *cp;
+	int ret;
 
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(dev);
-	old = hv_dev->driver_override;
-	if (strlen(driver_override)) {
-		hv_dev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		hv_dev->driver_override = NULL;
-	}
-	device_unlock(dev);
-
-	kfree(old);
+	ret = driver_set_override(dev, &hv_dev->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/pci/pci-sysfs.c

···
 				     const char *buf, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
-	char *driver_override, *old, *cp;
+	int ret;
 
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(dev);
-	old = pdev->driver_override;
-	if (strlen(driver_override)) {
-		pdev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		pdev->driver_override = NULL;
-	}
-	device_unlock(dev);
-
-	kfree(old);
+	ret = driver_set_override(dev, &pdev->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/rpmsg/rpmsg_core.c

···
 	      const char *buf, size_t sz)				\
 {									\
 	struct rpmsg_device *rpdev = to_rpmsg_device(dev);		\
-	char *new, *old;						\
+	const char *old;						\
+	char *new;							\
 									\
 	new = kstrndup(buf, sz, GFP_KERNEL);				\
 	if (!new)							\
···
 	.remove		= rpmsg_dev_remove,
 };
 
-int rpmsg_register_device(struct rpmsg_device *rpdev)
+/*
+ * A helper for registering rpmsg device with driver override and name.
+ * Drivers should not be using it, but instead rpmsg_register_device().
+ */
+int rpmsg_register_device_override(struct rpmsg_device *rpdev,
+				   const char *driver_override)
 {
 	struct device *dev = &rpdev->dev;
 	int ret;
 
-	dev_set_name(&rpdev->dev, "%s.%s.%d.%d", dev_name(dev->parent),
+	if (driver_override)
+		strcpy(rpdev->id.name, driver_override);
+
+	dev_set_name(dev, "%s.%s.%d.%d", dev_name(dev->parent),
 		     rpdev->id.name, rpdev->src, rpdev->dst);
 
-	rpdev->dev.bus = &rpmsg_bus;
+	dev->bus = &rpmsg_bus;
 
-	ret = device_register(&rpdev->dev);
+	device_initialize(dev);
+	if (driver_override) {
+		ret = driver_set_override(dev, &rpdev->driver_override,
+					  driver_override,
+					  strlen(driver_override));
+		if (ret) {
+			dev_err(dev, "device_set_override failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	ret = device_add(dev);
 	if (ret) {
-		dev_err(dev, "device_register failed: %d\n", ret);
-		put_device(&rpdev->dev);
+		dev_err(dev, "device_add failed: %d\n", ret);
+		kfree(rpdev->driver_override);
+		rpdev->driver_override = NULL;
+		put_device(dev);
 	}
 
 	return ret;
+}
+EXPORT_SYMBOL(rpmsg_register_device_override);
+
+int rpmsg_register_device(struct rpmsg_device *rpdev)
+{
+	return rpmsg_register_device_override(rpdev, NULL);
 }
 EXPORT_SYMBOL(rpmsg_register_device);
 

drivers/rpmsg/rpmsg_internal.h

···
  */
 static inline int rpmsg_ctrldev_register_device(struct rpmsg_device *rpdev)
 {
-	strcpy(rpdev->id.name, "rpmsg_ctrl");
-	rpdev->driver_override = "rpmsg_ctrl";
-
-	return rpmsg_register_device(rpdev);
+	return rpmsg_register_device_override(rpdev, "rpmsg_ctrl");
 }
 
 #endif

drivers/rpmsg/rpmsg_ns.c

···
  */
 int rpmsg_ns_register_device(struct rpmsg_device *rpdev)
 {
-	strcpy(rpdev->id.name, "rpmsg_ns");
-	rpdev->driver_override = "rpmsg_ns";
 	rpdev->src = RPMSG_NS_ADDR;
 	rpdev->dst = RPMSG_NS_ADDR;
 
-	return rpmsg_register_device(rpdev);
+	return rpmsg_register_device_override(rpdev, "rpmsg_ns");
 }
 EXPORT_SYMBOL(rpmsg_ns_register_device);
 

drivers/s390/cio/cio.h

···
 	struct work_struct todo_work;
 	struct schib_config config;
 	u64 dma_mask;
-	char *driver_override; /* Driver name to force a match */
+	/*
+	 * Driver name to force a match.  Do not set directly, because core
+	 * frees it.  Use driver_set_override() to set or clear it.
+	 */
+	const char *driver_override;
 } __attribute__ ((aligned(8)));
 
 DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);

drivers/s390/cio/css.c

···
 				     const char *buf, size_t count)
 {
 	struct subchannel *sch = to_subchannel(dev);
-	char *driver_override, *old, *cp;
+	int ret;
 
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(dev);
-	old = sch->driver_override;
-	if (strlen(driver_override)) {
-		sch->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		sch->driver_override = NULL;
-	}
-	device_unlock(dev);
-
-	kfree(old);
+	ret = driver_set_override(dev, &sch->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/slimbus/qcom-ngd-ctrl.c

···
 	const struct of_device_id *match;
 	struct device_node *node;
 	u32 id;
+	int ret;
 
 	match = of_match_node(qcom_slim_ngd_dt_match, parent->of_node);
 	data = match->data;
···
 		}
 		ngd->id = id;
 		ngd->pdev->dev.parent = parent;
-		ngd->pdev->driver_override = QCOM_SLIM_NGD_DRV_NAME;
+
+		ret = driver_set_override(&ngd->pdev->dev,
+					  &ngd->pdev->driver_override,
+					  QCOM_SLIM_NGD_DRV_NAME,
+					  strlen(QCOM_SLIM_NGD_DRV_NAME));
+		if (ret) {
+			platform_device_put(ngd->pdev);
+			kfree(ngd);
+			of_node_put(node);
+			return ret;
+		}
 		ngd->pdev->dev.of_node = node;
 		ctrl->ngd = ngd;
 

drivers/spi/spi.c

···
 				     const char *buf, size_t count)
 {
 	struct spi_device *spi = to_spi_device(dev);
-	const char *end = memchr(buf, '\n', count);
-	const size_t len = end ? end - buf : count;
-	const char *driver_override, *old;
+	int ret;
 
-	/* We need to keep extra room for a newline when displaying value */
-	if (len >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, len, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	device_lock(dev);
-	old = spi->driver_override;
-	if (len) {
-		spi->driver_override = driver_override;
-	} else {
-		/* Empty string, disable driver override */
-		spi->driver_override = NULL;
-		kfree(driver_override);
-	}
-	device_unlock(dev);
-	kfree(old);
+	ret = driver_set_override(dev, &spi->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

drivers/vdpa/vdpa.c

···
 				     const char *buf, size_t count)
 {
 	struct vdpa_device *vdev = dev_to_vdpa(dev);
-	const char *driver_override, *old;
-	char *cp;
+	int ret;
 
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(dev);
-	old = vdev->driver_override;
-	if (strlen(driver_override)) {
-		vdev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		vdev->driver_override = NULL;
-	}
-	device_unlock(dev);
-
-	kfree(old);
+	ret = driver_set_override(dev, &vdev->driver_override, buf, count);
+	if (ret)
+		return ret;
 
 	return count;
 }

fs/kernfs/dir.c

···
 #include "kernfs-internal.h"
 
 static DEFINE_SPINLOCK(kernfs_rename_lock);	/* kn->parent and ->name */
-static char kernfs_pr_cont_buf[PATH_MAX];	/* protected by rename_lock */
+/*
+ * Don't use rename_lock to piggy back on pr_cont_buf. We don't want to
+ * call pr_cont() while holding rename_lock. Because sometimes pr_cont()
+ * will perform wakeups when releasing console_sem. Holding rename_lock
+ * will introduce deadlock if the scheduler reads the kernfs_name in the
+ * wakeup path.
+ */
+static DEFINE_SPINLOCK(kernfs_pr_cont_lock);
+static char kernfs_pr_cont_buf[PATH_MAX];	/* protected by pr_cont_lock */
 static DEFINE_SPINLOCK(kernfs_idr_lock);	/* root->ino_idr */
 
 #define rb_to_kn(X) rb_entry((X), struct kernfs_node, rb)
···
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&kernfs_rename_lock, flags);
+	spin_lock_irqsave(&kernfs_pr_cont_lock, flags);
 
-	kernfs_name_locked(kn, kernfs_pr_cont_buf, sizeof(kernfs_pr_cont_buf));
+	kernfs_name(kn, kernfs_pr_cont_buf, sizeof(kernfs_pr_cont_buf));
 	pr_cont("%s", kernfs_pr_cont_buf);
 
-	spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+	spin_unlock_irqrestore(&kernfs_pr_cont_lock, flags);
 }
 
 /**
···
 	unsigned long flags;
 	int sz;
 
-	spin_lock_irqsave(&kernfs_rename_lock, flags);
+	spin_lock_irqsave(&kernfs_pr_cont_lock, flags);
 
-	sz = kernfs_path_from_node_locked(kn, NULL, kernfs_pr_cont_buf,
-					  sizeof(kernfs_pr_cont_buf));
+	sz = kernfs_path_from_node(kn, NULL, kernfs_pr_cont_buf,
+				   sizeof(kernfs_pr_cont_buf));
 	if (sz < 0) {
 		pr_cont("(error)");
 		goto out;
···
 	pr_cont("%s", kernfs_pr_cont_buf);
 
 out:
-	spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+	spin_unlock_irqrestore(&kernfs_pr_cont_lock, flags);
 }
 
 /**
···
 
 	lockdep_assert_held_read(&kernfs_root(parent)->kernfs_rwsem);
 
-	/* grab kernfs_rename_lock to piggy back on kernfs_pr_cont_buf */
-	spin_lock_irq(&kernfs_rename_lock);
+	spin_lock_irq(&kernfs_pr_cont_lock);
 
 	len = strlcpy(kernfs_pr_cont_buf, path, sizeof(kernfs_pr_cont_buf));
 
 	if (len >= sizeof(kernfs_pr_cont_buf)) {
-		spin_unlock_irq(&kernfs_rename_lock);
+		spin_unlock_irq(&kernfs_pr_cont_lock);
 		return NULL;
 	}
 
···
 		parent = kernfs_find_ns(parent, name, ns);
 	}
 
-	spin_unlock_irq(&kernfs_rename_lock);
+	spin_unlock_irq(&kernfs_pr_cont_lock);
 
 	return parent;
 }

fs/kernfs/file.c

···
 static DEFINE_MUTEX(kernfs_open_file_mutex);
 
 struct kernfs_open_node {
-	atomic_t		refcnt;
 	atomic_t		event;
 	wait_queue_head_t	poll;
 	struct list_head	files; /* goes through kernfs_open_file.list */
···
 	}
 
 	on = kn->attr.open;
-	if (on) {
-		atomic_inc(&on->refcnt);
+	if (on)
 		list_add_tail(&of->list, &on->files);
-	}
 
 	spin_unlock_irq(&kernfs_open_node_lock);
 	mutex_unlock(&kernfs_open_file_mutex);
···
 	if (!new_on)
 		return -ENOMEM;
 
-	atomic_set(&new_on->refcnt, 0);
 	atomic_set(&new_on->event, 1);
 	init_waitqueue_head(&new_on->poll);
 	INIT_LIST_HEAD(&new_on->files);
···
 }
 
 /**
- *	kernfs_put_open_node - put kernfs_open_node
- *	@kn: target kernfs_nodet
+ *	kernfs_unlink_open_file - Unlink @of from @kn.
+ *
+ *	@kn: target kernfs_node
  *	@of: associated kernfs_open_file
  *
- *	Put @kn->attr.open and unlink @of from the files list.  If
- *	reference count reaches zero, disassociate and free it.
+ *	Unlink @of from list of @kn's associated open files. If list of
+ *	associated open files becomes empty, disassociate and free
+ *	kernfs_open_node.
  *
  *	LOCKING:
  *	None.
  */
-static void kernfs_put_open_node(struct kernfs_node *kn,
+static void kernfs_unlink_open_file(struct kernfs_node *kn,
 				 struct kernfs_open_file *of)
 {
 	struct kernfs_open_node *on = kn->attr.open;
···
 	if (of)
 		list_del(&of->list);
 
-	if (atomic_dec_and_test(&on->refcnt))
+	if (list_empty(&on->files))
 		kn->attr.open = NULL;
 	else
 		on = NULL;
···
 	return 0;
 
 err_put_node:
-	kernfs_put_open_node(kn, of);
+	kernfs_unlink_open_file(kn, of);
 err_seq_release:
 	seq_release(inode, file);
 err_free:
···
 		mutex_unlock(&kernfs_open_file_mutex);
 	}
 
-	kernfs_put_open_node(kn, of);
+	kernfs_unlink_open_file(kn, of);
 	seq_release(inode, filp);
 	kfree(of->prealloc_buf);
 	kfree(of);
···
 	if (!(kn->flags & (KERNFS_HAS_MMAP | KERNFS_HAS_RELEASE)))
 		return;
 
-	spin_lock_irq(&kernfs_open_node_lock);
-	on = kn->attr.open;
-	if (on)
-		atomic_inc(&on->refcnt);
-	spin_unlock_irq(&kernfs_open_node_lock);
-	if (!on)
+	/*
+	 * lockless opportunistic check is safe below because no one is adding to
+	 * ->attr.open at this point of time. This check allows early bail out
+	 * if ->attr.open is already NULL. kernfs_unlink_open_file makes
+	 * ->attr.open NULL only while holding kernfs_open_file_mutex so below
+	 * check under kernfs_open_file_mutex will ensure bailing out if
+	 * ->attr.open became NULL while waiting for the mutex.
+	 */
+	if (!kn->attr.open)
 		return;
 
 	mutex_lock(&kernfs_open_file_mutex);
+	if (!kn->attr.open) {
+		mutex_unlock(&kernfs_open_file_mutex);
+		return;
+	}
+
+	on = kn->attr.open;
 
 	list_for_each_entry(of, &on->files, list) {
 		struct inode *inode = file_inode(of->file);
···
 	}
 
 	mutex_unlock(&kernfs_open_file_mutex);
-
-	kernfs_put_open_node(kn, NULL);
 }
 
 /*

include/linux/amba/bus.h

···
 	unsigned int		cid;
 	struct amba_cs_uci_id	uci;
 	unsigned int		irq[AMBA_NR_IRQS];
-	char			*driver_override;
+	/*
+	 * Driver name to force a match.  Do not set directly, because core
+	 * frees it.  Use driver_set_override() to set or clear it.
+	 */
+	const char		*driver_override;
 };
 
 struct amba_driver {

include/linux/device.h

···
 };
 
 /**
+ * enum device_physical_location_panel - Describes which panel surface of the
+ * system's housing the device connection point resides on.
+ * @DEVICE_PANEL_TOP: Device connection point is on the top panel.
+ * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel.
+ * @DEVICE_PANEL_LEFT: Device connection point is on the left panel.
+ * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel.
+ * @DEVICE_PANEL_FRONT: Device connection point is on the front panel.
+ * @DEVICE_PANEL_BACK: Device connection point is on the back panel.
+ * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown.
+ */
+enum device_physical_location_panel {
+	DEVICE_PANEL_TOP,
+	DEVICE_PANEL_BOTTOM,
+	DEVICE_PANEL_LEFT,
+	DEVICE_PANEL_RIGHT,
+	DEVICE_PANEL_FRONT,
+	DEVICE_PANEL_BACK,
+	DEVICE_PANEL_UNKNOWN,
+};
+
+/**
+ * enum device_physical_location_vertical_position - Describes vertical
+ * position of the device connection point on the panel surface.
+ * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel.
+ * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel.
+ * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel.
+ */
+enum device_physical_location_vertical_position {
+	DEVICE_VERT_POS_UPPER,
+	DEVICE_VERT_POS_CENTER,
+	DEVICE_VERT_POS_LOWER,
+};
+
+/**
+ * enum device_physical_location_horizontal_position - Describes horizontal
+ * position of the device connection point on the panel surface.
+ * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel.
+ * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel.
+ * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel.
+ */
+enum device_physical_location_horizontal_position {
+	DEVICE_HORI_POS_LEFT,
+	DEVICE_HORI_POS_CENTER,
+	DEVICE_HORI_POS_RIGHT,
+};
+
+/**
+ * struct device_physical_location - Device data related to physical location
+ * of the device connection point.
+ * @panel: Panel surface of the system's housing that the device connection
+ *         point resides on.
+ * @vertical_position: Vertical position of the device connection point within
+ *                     the panel.
+ * @horizontal_position: Horizontal position of the device connection point
+ *                       within the panel.
+ * @dock: Set if the device connection point resides in a docking station or
+ *        port replicator.
+ * @lid: Set if this device connection point resides on the lid of laptop
+ *       system.
+ */
+struct device_physical_location {
+	enum device_physical_location_panel panel;
+	enum device_physical_location_vertical_position vertical_position;
+	enum device_physical_location_horizontal_position horizontal_position;
+	bool dock;
+	bool lid;
+};
+
+/**
  * struct device - The basic device structure
  * @parent:	The device's "parent" device, the device to which it is attached.
  * 		In most cases, a parent device is some sort of bus or host
···
  * 		device (i.e. the bus driver that discovered the device).
  * @iommu_group: IOMMU group the device belongs to.
  * @iommu:	Per device generic IOMMU runtime data
+ * @physical_location: Describes physical location of the device connection
+ *		point in the system housing.
  * @removable:  Whether the device can be removed from the system. This
  *              should be set by the subsystem / bus driver that discovered
  *              the device.
···
 	void	(*release)(struct device *dev);
 	struct iommu_group	*iommu_group;
 	struct dev_iommu	*iommu;
+
+	struct device_physical_location *physical_location;
 
 	enum device_removable	removable;
 

include/linux/device/driver.h

···
 extern void driver_remove_file(struct device_driver *driver,
 			       const struct driver_attribute *attr);
 
+int driver_set_override(struct device *dev, const char **override,
+			const char *s, size_t len);
 extern int __must_check driver_for_each_device(struct device_driver *drv,
 					       struct device *start,
 					       void *data,

include/linux/export.h

···
 #ifndef _LINUX_EXPORT_H
 #define _LINUX_EXPORT_H
 
+#include <linux/stringify.h>
+
 /*
  * Export symbols from the kernel to modules.  Forked from module.h
  * to reduce the amount of pointless cruft we feed to gcc when only
···
 #endif /* CONFIG_MODULES */
 
 #ifdef DEFAULT_SYMBOL_NAMESPACE
-#include <linux/stringify.h>
 #define _EXPORT_SYMBOL(sym, sec)	__EXPORT_SYMBOL(sym, sec, __stringify(DEFAULT_SYMBOL_NAMESPACE))
 #else
 #define _EXPORT_SYMBOL(sym, sec)	__EXPORT_SYMBOL(sym, sec, "")
···
 
 #define EXPORT_SYMBOL(sym)		_EXPORT_SYMBOL(sym, "")
 #define EXPORT_SYMBOL_GPL(sym)		_EXPORT_SYMBOL(sym, "_gpl")
-#define EXPORT_SYMBOL_NS(sym, ns)	__EXPORT_SYMBOL(sym, "", #ns)
-#define EXPORT_SYMBOL_NS_GPL(sym, ns)	__EXPORT_SYMBOL(sym, "_gpl", #ns)
+#define EXPORT_SYMBOL_NS(sym, ns)	__EXPORT_SYMBOL(sym, "", __stringify(ns))
+#define EXPORT_SYMBOL_NS_GPL(sym, ns)	__EXPORT_SYMBOL(sym, "_gpl", __stringify(ns))
 
 #endif /* !__ASSEMBLY__ */
 

include/linux/firmware.h

···
 	void *priv;
 };
 
+/**
+ * enum fw_upload_err - firmware upload error codes
+ * @FW_UPLOAD_ERR_NONE: returned to indicate success
+ * @FW_UPLOAD_ERR_HW_ERROR: error signalled by hardware, see kernel log
+ * @FW_UPLOAD_ERR_TIMEOUT: SW timed out on handshake with HW/firmware
+ * @FW_UPLOAD_ERR_CANCELED: upload was cancelled by the user
+ * @FW_UPLOAD_ERR_BUSY: there is an upload operation already in progress
+ * @FW_UPLOAD_ERR_INVALID_SIZE: invalid firmware image size
+ * @FW_UPLOAD_ERR_RW_ERROR: read or write to HW failed, see kernel log
+ * @FW_UPLOAD_ERR_WEAROUT: FLASH device is approaching wear-out, wait & retry
+ * @FW_UPLOAD_ERR_MAX: Maximum error code marker
+ */
+enum fw_upload_err {
+	FW_UPLOAD_ERR_NONE,
+	FW_UPLOAD_ERR_HW_ERROR,
+	FW_UPLOAD_ERR_TIMEOUT,
+	FW_UPLOAD_ERR_CANCELED,
+	FW_UPLOAD_ERR_BUSY,
+	FW_UPLOAD_ERR_INVALID_SIZE,
+	FW_UPLOAD_ERR_RW_ERROR,
+	FW_UPLOAD_ERR_WEAROUT,
+	FW_UPLOAD_ERR_MAX
+};
+
+struct fw_upload {
+	void *dd_handle; /* reference to parent driver */
+	void *priv;	 /* firmware loader private fields */
+};
+
+/**
+ * struct fw_upload_ops - device specific operations to support firmware upload
+ * @prepare:		  Required: Prepare secure update
+ * @write:		  Required: The write() op receives the remaining
+ *			  size to be written and must return the actual
+ *			  size written or a negative error code. The write()
+ *			  op will be called repeatedly until all data is
+ *			  written.
+ * @poll_complete:	  Required: Check for the completion of the
+ *			  HW authentication/programming process.
+ * @cancel:		  Required: Request cancellation of update. This op
+ *			  is called from the context of a different kernel
+ *			  thread, so race conditions need to be considered.
+ * @cleanup:		  Optional: Complements the prepare()
+ *			  function and is called at the completion
+ *			  of the update, on success or failure, if the
+ *			  prepare function succeeded.
+ */
+struct fw_upload_ops {
+	enum fw_upload_err (*prepare)(struct fw_upload *fw_upload,
+				      const u8 *data, u32 size);
+	enum fw_upload_err (*write)(struct fw_upload *fw_upload,
+				    const u8 *data, u32 offset,
+				    u32 size, u32 *written);
+	enum fw_upload_err (*poll_complete)(struct fw_upload *fw_upload);
+	void (*cancel)(struct fw_upload *fw_upload);
+	void (*cleanup)(struct fw_upload *fw_upload);
+};
+
 struct module;
 struct device;
 
···
 					 void *buf, size_t size, size_t offset)
 {
 	return -EINVAL;
+}
+
+#endif
+
+#ifdef CONFIG_FW_UPLOAD
+
+struct fw_upload *
+firmware_upload_register(struct module *module, struct device *parent,
+			 const char *name, const struct fw_upload_ops *ops,
+			 void *dd_handle);
+void firmware_upload_unregister(struct fw_upload *fw_upload);
+
+#else
+
+static inline struct fw_upload *
+firmware_upload_register(struct module *module, struct device *parent,
+			 const char *name, const struct fw_upload_ops *ops,
+			 void *dd_handle)
+{
+		return ERR_PTR(-EINVAL);
+}
+
+static inline void firmware_upload_unregister(struct fw_upload *fw_upload)
+{
 }
 
 #endif

include/linux/fsl/mc.h

···
  * @regions: pointer to array of MMIO region entries
  * @irqs: pointer to array of pointers to interrupts allocated to this device
  * @resource: generic resource associated with this MC object device, if any.
- * @driver_override: driver name to force a match
+ * @driver_override: driver name to force a match; do not set directly,
+ *                   because core frees it; use driver_set_override() to
+ *                   set or clear it.
  *
  * Generic device object for MC object devices that are "attached" to a
  * MC bus.
···
 	struct fsl_mc_device_irq **irqs;
 	struct fsl_mc_resource *resource;
 	struct device_link *consumer_link;
-	char   *driver_override;
+	const char *driver_override;
 };
 
 #define to_fsl_mc_device(_dev) \

include/linux/hyperv.h

···
 	u16 device_id;
 
 	struct device device;
-	char *driver_override; /* Driver name to force a match */
+	/*
+	 * Driver name to force a match.  Do not set directly, because core
+	 * frees it.  Use driver_set_override() to set or clear it.
+	 */
+	const char *driver_override;
 
 	struct vmbus_channel *channel;
 	struct kset	     *channels_kset;

include/linux/pci.h

···
 	u16		acs_cap;	/* ACS Capability offset */
 	phys_addr_t	rom;		/* Physical address if not from BAR */
 	size_t		romlen;		/* Length if not from BAR */
-	char		*driver_override; /* Driver name to force a match */
+	/*
+	 * Driver name to force a match.  Do not set directly, because core
+	 * frees it.  Use driver_set_override() to set or clear it.
+	 */
+	const char	*driver_override;
 
 	unsigned long	priv_flags;	/* Private flags for the PCI driver */
 

include/linux/platform_device.h

···
 	struct resource	*resource;
 
 	const struct platform_device_id	*id_entry;
-	char *driver_override; /* Driver name to force a match */
+	/*
+	 * Driver name to force a match.  Do not set directly, because core
+	 * frees it.  Use driver_set_override() to set or clear it.
+	 */
+	const char *driver_override;
 
 	/* MFD cell pointer */
 	struct mfd_cell *mfd_cell;

include/linux/rpmsg.h

···
  * rpmsg_device - device that belong to the rpmsg bus
  * @dev: the device struct
  * @id: device id (used to match between rpmsg drivers and devices)
- * @driver_override: driver name to force a match
+ * @driver_override: driver name to force a match; do not set directly,
+ *                   because core frees it; use driver_set_override() to
+ *                   set or clear it.
  * @src: local address
  * @dst: destination address
  * @ept: the rpmsg endpoint of this channel
···
 struct rpmsg_device {
 	struct device dev;
 	struct rpmsg_device_id id;
-	char *driver_override;
+	const char *driver_override;
 	u32 src;
 	u32 dst;
 	struct rpmsg_endpoint *ept;
···
 
 #if IS_ENABLED(CONFIG_RPMSG)
 
+int rpmsg_register_device_override(struct rpmsg_device *rpdev,
+				   const char *driver_override);
 int rpmsg_register_device(struct rpmsg_device *rpdev);
 int rpmsg_unregister_device(struct device *parent,
 			    struct rpmsg_channel_info *chinfo);
···
 ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
 
 #else
+
+static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev,
+						 const char *driver_override)
+{
+	return -ENXIO;
+}
 
 static inline int rpmsg_register_device(struct rpmsg_device *rpdev)
 {

include/linux/spi/spi.h

···
  *	for driver coldplugging, and in uevents used for hotplugging
  * @driver_override: If the name of a driver is written to this attribute, then
  *	the device will bind to the named driver and only the named driver.
+ *	Do not set directly, because core frees it; use driver_set_override() to
+ *	set or clear it.
  * @cs_gpiod: gpio descriptor of the chipselect line (optional, NULL when
  *	not using a GPIO line)
  * @word_delay: delay to be inserted between consecutive

include/linux/vdpa.h

···
  * struct vdpa_device - representation of a vDPA device
  * @dev: underlying device
  * @dma_dev: the actual device that is performing DMA
- * @driver_override: driver name to force a match
+ * @driver_override: driver name to force a match; do not set directly,
+ *                   because core frees it; use driver_set_override() to
+ *                   set or clear it.
  * @config: the configuration ops for this device.
  * @cf_lock: Protects get and set access to configuration layout.
  * @index: device index

include/trace/events/thermal_pressure.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM thermal_pressure
+
+#if !defined(_TRACE_THERMAL_PRESSURE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_THERMAL_PRESSURE_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(thermal_pressure_update,
+	TP_PROTO(int cpu, unsigned long thermal_pressure),
+	TP_ARGS(cpu, thermal_pressure),
+
+	TP_STRUCT__entry(
+		__field(unsigned long, thermal_pressure)
+		__field(int, cpu)
+	),
+
+	TP_fast_assign(
+		__entry->thermal_pressure = thermal_pressure;
+		__entry->cpu = cpu;
+	),
+
+	TP_printk("cpu=%d thermal_pressure=%lu", __entry->cpu, __entry->thermal_pressure)
+);
+#endif /* _TRACE_THERMAL_PRESSURE_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>

lib/test_firmware.c

···
 #define TEST_FIRMWARE_NAME	"test-firmware.bin"
 #define TEST_FIRMWARE_NUM_REQS	4
 #define TEST_FIRMWARE_BUF_SIZE	SZ_1K
+#define TEST_UPLOAD_MAX_SIZE	SZ_2K
+#define TEST_UPLOAD_BLK_SIZE	37	/* Avoid powers of two in testing */
 
 static DEFINE_MUTEX(test_fw_mutex);
 static const struct firmware *test_firmware;
+static LIST_HEAD(test_upload_list);
 
 struct test_batched_req {
 	u8 idx;
···
  * @reqs: stores all requests information
  * @read_fw_idx: index of thread from which we want to read firmware results
  *	from through the read_fw trigger.
+ * @upload_name: firmware name to be used with upload_read sysfs node
  * @test_result: a test may use this to collect the result from the call
  *	of the request_firmware*() calls used in their tests. In order of
  *	priority we always keep first any setup error. If no setup errors were
···
 	bool send_uevent;
 	u8 num_requests;
 	u8 read_fw_idx;
+	char *upload_name;
 
 	/*
 	 * These below don't belong her but we'll move them once we create
···
 			    struct device *device);
 };
 
+struct upload_inject_err {
+	const char *prog;
+	enum fw_upload_err err_code;
+};
+
+struct test_firmware_upload {
+	char *name;
+	struct list_head node;
+	char *buf;
+	size_t size;
+	bool cancel_request;
+	struct upload_inject_err inject;
+	struct fw_upload *fwl;
+};
+
 static struct test_config *test_fw_config;
+
+static struct test_firmware_upload *upload_lookup_name(const char *name)
+{
+	struct test_firmware_upload *tst;
+
+	list_for_each_entry(tst, &test_upload_list, node)
+		if (strncmp(name, tst->name, strlen(tst->name)) == 0)
+			return tst;
+
+	return NULL;
+}
 
 static ssize_t test_fw_misc_read(struct file *f, char __user *buf,
 				 size_t size, loff_t *offset)
···
 	test_fw_config->req_firmware = request_firmware;
 	test_fw_config->test_result = 0;
 	test_fw_config->reqs = NULL;
+	test_fw_config->upload_name = NULL;
 
 	return 0;
 
···
 			test_fw_config->sync_direct ? "true" : "false");
 	len += scnprintf(buf + len, PAGE_SIZE - len,
 			"read_fw_idx:\t%u\n", test_fw_config->read_fw_idx);
+	if (test_fw_config->upload_name)
+		len += scnprintf(buf + len, PAGE_SIZE - len,
+				"upload_name:\t%s\n",
+				test_fw_config->upload_name);
+	else
+		len += scnprintf(buf + len, PAGE_SIZE - len,
+				"upload_name:\tEMTPY\n");
 
 	mutex_unlock(&test_fw_mutex);
 
···
 	return config_test_show_str(buf, test_fw_config->name);
 }
 static DEVICE_ATTR_RW(config_name);
+
+static ssize_t config_upload_name_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct test_firmware_upload *tst;
+	int ret = count;
+
+	mutex_lock(&test_fw_mutex);
+	tst = upload_lookup_name(buf);
+	if (tst)
+		test_fw_config->upload_name = tst->name;
+	else
+		ret = -EINVAL;
+	mutex_unlock(&test_fw_mutex);
+
+	return ret;
+}
+
+static ssize_t config_upload_name_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	return config_test_show_str(buf, test_fw_config->upload_name);
+}
+static DEVICE_ATTR_RW(config_upload_name);
 
 static ssize_t config_num_requests_store(struct device *dev,
 					 struct device_attribute *attr,
···
 }
 static DEVICE_ATTR_WO(trigger_batched_requests_async);
 
+static void upload_release(struct test_firmware_upload *tst)
+{
+	firmware_upload_unregister(tst->fwl);
+	kfree(tst->buf);
+	kfree(tst->name);
+	kfree(tst);
+}
+
+static void upload_release_all(void)
+{
+	struct test_firmware_upload *tst, *tmp;
+
+	list_for_each_entry_safe(tst, tmp, &test_upload_list, node) {
+		list_del(&tst->node);
+		upload_release(tst);
+	}
+	test_fw_config->upload_name = NULL;
+}
+
+/*
+ * This table is replicated from .../firmware_loader/sysfs_upload.c
+ * and needs to be kept in sync.
+ */
+static const char * const fw_upload_err_str[] = {
+	[FW_UPLOAD_ERR_NONE]	     = "none",
+	[FW_UPLOAD_ERR_HW_ERROR]     = "hw-error",
+	[FW_UPLOAD_ERR_TIMEOUT]	     = "timeout",
+	[FW_UPLOAD_ERR_CANCELED]     = "user-abort",
+	[FW_UPLOAD_ERR_BUSY]	     = "device-busy",
+	[FW_UPLOAD_ERR_INVALID_SIZE] = "invalid-file-size",
+	[FW_UPLOAD_ERR_RW_ERROR]     = "read-write-error",
+	[FW_UPLOAD_ERR_WEAROUT]	     = "flash-wearout",
+};
+
+static void upload_err_inject_error(struct test_firmware_upload *tst,
+				    const u8 *p, const char *prog)
+{
+	enum fw_upload_err err;
+
+	for (err = FW_UPLOAD_ERR_NONE + 1; err < FW_UPLOAD_ERR_MAX; err++) {
+		if (strncmp(p, fw_upload_err_str[err],
+			    strlen(fw_upload_err_str[err])) == 0) {
+			tst->inject.prog = prog;
+			tst->inject.err_code = err;
+			return;
+		}
+	}
+}
+
+static void upload_err_inject_prog(struct test_firmware_upload *tst,
+				   const u8 *p)
+{
+	static const char * const progs[] = {
+		"preparing:", "transferring:", "programming:"
+	};
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(progs); i++) {
+		if (strncmp(p, progs[i], strlen(progs[i])) == 0) {
+			upload_err_inject_error(tst, p + strlen(progs[i]),
+						progs[i]);
+			return;
+		}
+	}
+}
+
+#define FIVE_MINUTES_MS	(5 * 60 * 1000)
+static enum fw_upload_err
+fw_upload_wait_on_cancel(struct test_firmware_upload *tst)
+{
+	int ms_delay;
+
+	for (ms_delay = 0; ms_delay < FIVE_MINUTES_MS; ms_delay += 100) {
+		msleep(100);
+		if (tst->cancel_request)
+			return FW_UPLOAD_ERR_CANCELED;
+	}
+	return FW_UPLOAD_ERR_NONE;
+}
+
+static enum fw_upload_err test_fw_upload_prepare(struct fw_upload *fwl,
+						 const u8 *data, u32 size)
+{
+	struct test_firmware_upload *tst = fwl->dd_handle;
+	enum fw_upload_err ret = FW_UPLOAD_ERR_NONE;
+	const char *progress = "preparing:";
+
+	tst->cancel_request = false;
+
+	if (!size || size > TEST_UPLOAD_MAX_SIZE) {
+		ret = FW_UPLOAD_ERR_INVALID_SIZE;
+		goto err_out;
+	}
+
+	if (strncmp(data, "inject:", strlen("inject:")) == 0)
+		upload_err_inject_prog(tst, data + strlen("inject:"));
+
+	memset(tst->buf, 0, TEST_UPLOAD_MAX_SIZE);
+	tst->size = size;
+
+	if (tst->inject.err_code == FW_UPLOAD_ERR_NONE ||
+	    strncmp(tst->inject.prog, progress, strlen(progress)) != 0)
+		return FW_UPLOAD_ERR_NONE;
+
+	if (tst->inject.err_code == FW_UPLOAD_ERR_CANCELED)
+		ret = fw_upload_wait_on_cancel(tst);
+	else
+		ret = tst->inject.err_code;
+
+err_out:
+	/*
+	 * The cleanup op only executes if the prepare op succeeds.
+	 * If the prepare op fails, it must do it's own clean-up.
+	 */
+	tst->inject.err_code = FW_UPLOAD_ERR_NONE;
+	tst->inject.prog = NULL;
+
+	return ret;
+}
+
+static enum fw_upload_err test_fw_upload_write(struct fw_upload *fwl,
+					       const u8 *data, u32 offset,
+					       u32 size, u32 *written)
+{
+	struct test_firmware_upload *tst = fwl->dd_handle;
+	const char *progress = "transferring:";
+	u32 blk_size;
+
+	if (tst->cancel_request)
+		return FW_UPLOAD_ERR_CANCELED;
+
+	blk_size = min_t(u32, TEST_UPLOAD_BLK_SIZE, size);
+	memcpy(tst->buf + offset, data + offset, blk_size);
+
+	*written = blk_size;
+
+	if (tst->inject.err_code == FW_UPLOAD_ERR_NONE ||
+	    strncmp(tst->inject.prog, progress, strlen(progress)) != 0)
+		return FW_UPLOAD_ERR_NONE;
+
+	if (tst->inject.err_code == FW_UPLOAD_ERR_CANCELED)
+		return fw_upload_wait_on_cancel(tst);
+
+	return tst->inject.err_code;
+}
+
+static enum fw_upload_err test_fw_upload_complete(struct fw_upload *fwl)
+{
+	struct test_firmware_upload *tst = fwl->dd_handle;
+	const char *progress = "programming:";
+
+	if (tst->cancel_request)
+		return FW_UPLOAD_ERR_CANCELED;
+
+	if (tst->inject.err_code == FW_UPLOAD_ERR_NONE ||
+	    strncmp(tst->inject.prog, progress, strlen(progress)) != 0)
+		return FW_UPLOAD_ERR_NONE;
+
+	if (tst->inject.err_code == FW_UPLOAD_ERR_CANCELED)
+		return fw_upload_wait_on_cancel(tst);
+
+	return tst->inject.err_code;
+}
+
+static void test_fw_upload_cancel(struct fw_upload *fwl)
+{
+	struct test_firmware_upload *tst = fwl->dd_handle;
+
+	tst->cancel_request = true;
+}
+
+static void test_fw_cleanup(struct fw_upload *fwl)
+{
+	struct test_firmware_upload *tst = fwl->dd_handle;
+
+	tst->inject.err_code = FW_UPLOAD_ERR_NONE;
+	tst->inject.prog = NULL;
+}
+
+static const struct fw_upload_ops upload_test_ops = {
+	.prepare = test_fw_upload_prepare,
+	.write = test_fw_upload_write,
+	.poll_complete = test_fw_upload_complete,
+	.cancel = test_fw_upload_cancel,
+	.cleanup = test_fw_cleanup
+};
+
+static ssize_t upload_register_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct test_firmware_upload *tst;
+	struct fw_upload *fwl;
+	char *name;
+	int ret;
+
+	name = kstrndup(buf, count, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
+
+	mutex_lock(&test_fw_mutex);
+	tst = upload_lookup_name(name);
+	if (tst) {
+		ret = -EEXIST;
+		goto free_name;
+	}
+
+	tst = kzalloc(sizeof(*tst), GFP_KERNEL);
+	if (!tst) {
+		ret = -ENOMEM;
+		goto free_name;
+	}
+
+	tst->name = name;
+	tst->buf = kzalloc(TEST_UPLOAD_MAX_SIZE, GFP_KERNEL);
+	if (!tst->buf) {
+		ret = -ENOMEM;
+		goto free_tst;
+	}
+
+	fwl = firmware_upload_register(THIS_MODULE, dev, tst->name,
+				       &upload_test_ops, tst);
+	if (IS_ERR(fwl)) {
+		ret = PTR_ERR(fwl);
+		goto free_buf;
+	}
+
+	tst->fwl = fwl;
+	list_add_tail(&tst->node, &test_upload_list);
+	mutex_unlock(&test_fw_mutex);
+	return count;
+
+free_buf:
+	kfree(tst->buf);
+
+free_tst:
+	kfree(tst);
+
+free_name:
+	mutex_unlock(&test_fw_mutex);
+	kfree(name);
+
+	return ret;
+}
+static DEVICE_ATTR_WO(upload_register);
+
+static ssize_t upload_unregister_store(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf, size_t count)
+{
+	struct test_firmware_upload *tst;
+	int ret = count;
+
+	mutex_lock(&test_fw_mutex);
+	tst = upload_lookup_name(buf);
+	if (!tst) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (test_fw_config->upload_name == tst->name)
+		test_fw_config->upload_name = NULL;
+
+	list_del(&tst->node);
+	upload_release(tst);
+
+out:
+	mutex_unlock(&test_fw_mutex);
+	return ret;
+}
+static DEVICE_ATTR_WO(upload_unregister);
+
 static ssize_t test_result_show(struct device *dev,
 				struct device_attribute *attr,
 				char *buf)
···
 }
 static DEVICE_ATTR_RO(read_firmware);
 
+static ssize_t upload_read_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct test_firmware_upload *tst = NULL;
+	struct test_firmware_upload *tst_iter;
+	int ret = -EINVAL;
+
+	if (!test_fw_config->upload_name) {
+		pr_err("Set config_upload_name before using upload_read\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&test_fw_mutex);
+	list_for_each_entry(tst_iter, &test_upload_list, node)
+		if (tst_iter->name == test_fw_config->upload_name) {
+			tst = tst_iter;
+			break;
+		}
+
+	if (!tst) {
+		pr_err("Firmware name not found: %s\n",
+		       test_fw_config->upload_name);
+		goto out;
+	}
+
+	if (tst->size > PAGE_SIZE) {
+		pr_err("Testing interface must use PAGE_SIZE firmware for now\n");
+		goto out;
+	}
+
+	memcpy(buf, tst->buf, tst->size);
+	ret = tst->size;
+out:
+	mutex_unlock(&test_fw_mutex);
+	return ret;
+}
+static DEVICE_ATTR_RO(upload_read);
+
 #define TEST_FW_DEV_ATTR(name)          &dev_attr_##name.attr
 
 static struct attribute *test_dev_attrs[] = {
···
 	TEST_FW_DEV_ATTR(config_sync_direct),
 	TEST_FW_DEV_ATTR(config_send_uevent),
 	TEST_FW_DEV_ATTR(config_read_fw_idx),
+	TEST_FW_DEV_ATTR(config_upload_name),
 
 	/* These don't use the config at all - they could be ported! */
 	TEST_FW_DEV_ATTR(trigger_request),
···
 	TEST_FW_DEV_ATTR(release_all_firmware),
 	TEST_FW_DEV_ATTR(test_result),
 	TEST_FW_DEV_ATTR(read_firmware),
+	TEST_FW_DEV_ATTR(upload_read),
+	TEST_FW_DEV_ATTR(upload_register),
+	TEST_FW_DEV_ATTR(upload_unregister),
 	NULL,
 };
 
···
 	mutex_lock(&test_fw_mutex);
 	release_firmware(test_firmware);
 	misc_deregister(&test_fw_misc_device);
+	upload_release_all();
 	__test_firmware_config_free();
 	kfree(test_fw_config);
 	mutex_unlock(&test_fw_mutex);

scripts/get_abi.pl

···
 
 =head1 NAME
 
-abi_book.pl - parse the Linux ABI files and produce a ReST book.
+get_abi.pl - parse the Linux ABI files and produce a ReST book.
 
 =head1 SYNOPSIS
 
-B<abi_book.pl> [--debug <level>] [--enable-lineno] [--man] [--help]
+B<get_abi.pl> [--debug <level>] [--enable-lineno] [--man] [--help]
 	       [--(no-)rst-source] [--dir=<dir>] [--show-hints]
 	       [--search-string <regex>]
 	       <COMMAND> [<ARGUMENT>]

tools/testing/selftests/firmware/Makefile

···
          -O2
 
 TEST_PROGS := fw_run_tests.sh
-TEST_FILES := fw_fallback.sh fw_filesystem.sh fw_lib.sh
+TEST_FILES := fw_fallback.sh fw_filesystem.sh fw_upload.sh fw_lib.sh
 TEST_GEN_FILES := fw_namespace
 
 include ../lib.mk

tools/testing/selftests/firmware/config

···
 CONFIG_FW_LOADER_USER_HELPER=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
+CONFIG_FW_UPLOAD=y

tools/testing/selftests/firmware/fw_filesystem.sh

···
 TEST_DIR=$(dirname $0)
 source $TEST_DIR/fw_lib.sh
 
+RUN_XZ="xz -C crc32 --lzma2=dict=2MiB"
+RUN_ZSTD="zstd -q"
+
 check_mods
 check_setup
 verify_reqs
···
 	else
 		fwfile="$FW"
 	fi
-	if [ "$1" = "xzonly" ]; then
+	if [ "$1" = "componly" ]; then
 		fwfile="${fwfile}-orig"
 	fi
 	for i in $(seq 0 3); do
···
 		fwfile="${FW}"
 	fi
 
-	if [ "$1" = "xzonly" ]; then
+	if [ "$1" = "componly" ]; then
 		fwfile="${fwfile}-orig"
 	fi
 
···
 	config_unset_uevent
 	RANDOM_FILE_PATH=$(setup_random_file)
 	RANDOM_FILE="$(basename $RANDOM_FILE_PATH)"
-	if [ "$2" = "both" ]; then
-		xz -9 -C crc32 -k $RANDOM_FILE_PATH
-	elif [ "$2" = "xzonly" ]; then
-		xz -9 -C crc32 $RANDOM_FILE_PATH
+	if [ -n "$2" -a "$2" != "normal" ]; then
+		compress_"$2"_"$COMPRESS_FORMAT" $RANDOM_FILE_PATH
 	fi
 	config_set_name $RANDOM_FILE
 	config_trigger_async
···
 	echo "OK"
 }
 
+do_tests ()
+{
+	mode="$1"
+	suffix="$2"
+
+	for i in $(seq 1 5); do
+		test_batched_request_firmware$suffix $i $mode
+	done
+
+	for i in $(seq 1 5); do
+		test_batched_request_firmware_into_buf$suffix $i $mode
+	done
+
+	for i in $(seq 1 5); do
+		test_batched_request_firmware_direct$suffix $i $mode
+	done
+
+	for i in $(seq 1 5); do
+		test_request_firmware_nowait_uevent$suffix $i $mode
+	done
+
+	for i in $(seq 1 5); do
+		test_request_firmware_nowait_custom$suffix $i $mode
+	done
+}
+
 # Only continue if batched request triggers are present on the
 # test-firmware driver
 test_config_present
···
 # test with the file present
 echo
 echo "Testing with the file present..."
-for i in $(seq 1 5); do
-	test_batched_request_firmware $i normal
-done
-
-for i in $(seq 1 5); do
-	test_batched_request_firmware_into_buf $i normal
-done
-
-for i in $(seq 1 5); do
-	test_batched_request_firmware_direct $i normal
-done
-
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_uevent $i normal
-done
-
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_custom $i normal
-done
+do_tests normal
 
 # Partial loads cannot use fallback, so do not repeat tests.
 test_request_partial_firmware_into_buf 0 10
···
 # a hung task, which would require a hard reset.
 echo
 echo "Testing with the file missing..."
-for i in $(seq 1 5); do
-	test_batched_request_firmware_nofile $i
-done
-
-for i in $(seq 1 5); do
-	test_batched_request_firmware_into_buf_nofile $i
-done
-
-for i in $(seq 1 5); do
-	test_batched_request_firmware_direct_nofile $i
-done
-
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_uevent_nofile $i
-done
-
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_custom_nofile $i
-done
+do_tests nofile _nofile
 
 # Partial loads cannot use fallback, so do not repeat tests.
 test_request_partial_firmware_into_buf_nofile 0 10
···
 test_request_partial_firmware_into_buf_nofile 1 6
 test_request_partial_firmware_into_buf_nofile 2 10
 
-test "$HAS_FW_LOADER_COMPRESS" != "yes" && exit 0
+test_request_firmware_compressed ()
+{
+	export COMPRESS_FORMAT="$1"
 
-# test with both files present
-xz -9 -C crc32 -k $FW
-config_set_name $NAME
-echo
-echo "Testing with both plain and xz files present..."
-for i in $(seq 1 5); do
-	test_batched_request_firmware $i both
-done
+	# test with both files present
+	compress_both_"$COMPRESS_FORMAT" $FW
+	compress_both_"$COMPRESS_FORMAT" $FW_INTO_BUF
 
-for i in $(seq 1 5); do
-	test_batched_request_firmware_into_buf $i both
-done
+	config_set_name $NAME
+	echo
+	echo "Testing with both plain and $COMPRESS_FORMAT files present..."
+	do_tests both
 
-for i in $(seq 1 5); do
-	test_batched_request_firmware_direct $i both
-done
+	# test with only compressed file present
+	mv "$FW" "${FW}-orig"
+	mv "$FW_INTO_BUF" "${FW_INTO_BUF}-orig"
 
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_uevent $i both
-done
+	config_set_name $NAME
+	echo
+	echo "Testing with only $COMPRESS_FORMAT file present..."
+	do_tests componly
 
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_custom $i both
-done
+	mv "${FW}-orig" "$FW"
+	mv "${FW_INTO_BUF}-orig" "$FW_INTO_BUF"
+}
 
-# test with only xz file present
-mv "$FW" "${FW}-orig"
-echo
-echo "Testing with only xz file present..."
-for i in $(seq 1 5); do
-	test_batched_request_firmware $i xzonly
-done
+compress_both_XZ ()
+{
+	$RUN_XZ -k "$@"
+}
 
-for i in $(seq 1 5); do
-	test_batched_request_firmware_into_buf $i xzonly
-done
+compress_componly_XZ ()
+{
+	$RUN_XZ "$@"
+}
 
-for i in $(seq 1 5); do
-	test_batched_request_firmware_direct $i xzonly
-done
+compress_both_ZSTD ()
+{
+	$RUN_ZSTD -k "$@"
+}
 
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_uevent $i xzonly
-done
+compress_componly_ZSTD ()
+{
+	$RUN_ZSTD --rm "$@"
+}
 
-for i in $(seq 1 5); do
-	test_request_firmware_nowait_custom $i xzonly
-done
+if test "$HAS_FW_LOADER_COMPRESS_XZ" = "yes"; then
+	test_request_firmware_compressed XZ
+fi
+
+if test "$HAS_FW_LOADER_COMPRESS_ZSTD" = "yes"; then
+	test_request_firmware_compressed ZSTD
+fi
 
 exit 0

tools/testing/selftests/firmware/fw_lib.sh

···
 {
 	HAS_FW_LOADER_USER_HELPER="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER=y)"
 	HAS_FW_LOADER_USER_HELPER_FALLBACK="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y)"
-	HAS_FW_LOADER_COMPRESS="$(kconfig_has CONFIG_FW_LOADER_COMPRESS=y)"
+	HAS_FW_LOADER_COMPRESS_XZ="$(kconfig_has CONFIG_FW_LOADER_COMPRESS_XZ=y)"
+	HAS_FW_LOADER_COMPRESS_ZSTD="$(kconfig_has CONFIG_FW_LOADER_COMPRESS_ZSTD=y)"
+	HAS_FW_UPLOAD="$(kconfig_has CONFIG_FW_UPLOAD=y)"
 	PROC_FW_IGNORE_SYSFS_FALLBACK="0"
 	PROC_FW_FORCE_SYSFS_FALLBACK="0"
 
···
 
 	OLD_FWPATH="$(cat /sys/module/firmware_class/parameters/path)"
 
-	if [ "$HAS_FW_LOADER_COMPRESS" = "yes" ]; then
+	if [ "$HAS_FW_LOADER_COMPRESS_XZ" = "yes" ]; then
 		if ! which xz 2> /dev/null > /dev/null; then
-			HAS_FW_LOADER_COMPRESS=""
+			HAS_FW_LOADER_COMPRESS_XZ=""
+		fi
+	fi
+	if [ "$HAS_FW_LOADER_COMPRESS_ZSTD" = "yes" ]; then
+		if ! which zstd 2> /dev/null > /dev/null; then
+			HAS_FW_LOADER_COMPRESS_ZSTD=""
 		fi
 	fi
 }
···
 	if [ "$TEST_REQS_FW_SYSFS_FALLBACK" = "yes" ]; then
 		if [ ! "$HAS_FW_LOADER_USER_HELPER" = "yes" ]; then
 			echo "usermode helper disabled so ignoring test"
+			exit 0
+		fi
+	fi
+	if [ "$TEST_REQS_FW_UPLOAD" = "yes" ]; then
+		if [ ! "$HAS_FW_UPLOAD" = "yes" ]; then
+			echo "firmware upload disabled so ignoring test"
 			exit 0
 		fi
 	fi

tools/testing/selftests/firmware/fw_run_tests.sh

···
 	proc_set_force_sysfs_fallback $1
 	proc_set_ignore_sysfs_fallback $2
 	$TEST_DIR/fw_fallback.sh
+
+	proc_set_force_sysfs_fallback $1
+	proc_set_ignore_sysfs_fallback $2
+	$TEST_DIR/fw_upload.sh
 }
 
 run_test_config_0001()

tools/testing/selftests/firmware/fw_upload.sh

···
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# This validates the user-initiated fw upload mechanism of the firmware
+# loader. It verifies that one or more firmware devices can be created
+# for a device driver. It also verifies the data transfer, the
+# cancellation support, and the error flows.
+set -e
+
+TEST_REQS_FW_UPLOAD="yes"
+TEST_DIR=$(dirname $0)
+
+progress_states="preparing transferring  programming"
+errors="hw-error
+	timeout
+	device-busy
+	invalid-file-size
+	read-write-error
+	flash-wearout"
+error_abort="user-abort"
+fwname1=fw1
+fwname2=fw2
+fwname3=fw3
+
+source $TEST_DIR/fw_lib.sh
+
+check_mods
+check_setup
+verify_reqs
+
+trap "upload_finish" EXIT
+
+upload_finish() {
+	local fwdevs="$fwname1 $fwname2 $fwname3"
+
+	for name in $fwdevs; do
+		if [ -e "$DIR/$name" ]; then
+			echo -n "$name" > "$DIR"/upload_unregister
+		fi
+	done
+}
+
+upload_fw() {
+	local name="$1"
+	local file="$2"
+
+	echo 1 > "$DIR"/"$name"/loading
+	cat "$file" > "$DIR"/"$name"/data
+	echo 0 > "$DIR"/"$name"/loading
+}
+
+verify_fw() {
+	local name="$1"
+	local file="$2"
+
+	echo -n "$name" > "$DIR"/config_upload_name
+	if ! cmp "$file" "$DIR"/upload_read > /dev/null 2>&1; then
+		echo "$0: firmware compare for $name did not match" >&2
+		exit 1
+	fi
+
+	echo "$0: firmware upload for $name works" >&2
+	return 0
+}
+
+inject_error() {
+	local name="$1"
+	local status="$2"
+	local error="$3"
+
+	echo 1 > "$DIR"/"$name"/loading
+	echo -n "inject":"$status":"$error" > "$DIR"/"$name"/data
+	echo 0 > "$DIR"/"$name"/loading
+}
+
+await_status() {
+	local name="$1"
+	local expected="$2"
+	local status
+	local i
+
+	let i=0
+	while [ $i -lt 50 ]; do
+		status=$(cat "$DIR"/"$name"/status)
+		if [ "$status" = "$expected" ]; then
+			return 0;
+		fi
+		sleep 1e-03
+		let i=$i+1
+	done
+
+	echo "$0: Invalid status: Expected $expected, Actual $status" >&2
+	return 1;
+}
+
+await_idle() {
+	local name="$1"
+
+	await_status "$name" "idle"
+	return $?
+}
+
+expect_error() {
+	local name="$1"
+	local expected="$2"
+	local error=$(cat "$DIR"/"$name"/error)
+
+	if [ "$error" != "$expected" ]; then
+		echo "Invalid error: Expected $expected, Actual $error" >&2
+		return 1
+	fi
+
+	return 0
+}
+
+random_firmware() {
+	local bs="$1"
+	local count="$2"
+	local file=$(mktemp -p /tmp uploadfwXXX.bin)
+
+	dd if=/dev/urandom of="$file" bs="$bs" count="$count" > /dev/null 2>&1
+	echo "$file"
+}
+
+test_upload_cancel() {
+	local name="$1"
+	local status
+
+	for status in $progress_states; do
+		inject_error $name $status $error_abort
+		if ! await_status $name $status; then
+			exit 1
+		fi
+
+		echo 1 > "$DIR"/"$name"/cancel
+
+		if ! await_idle $name; then
+			exit 1
+		fi
+
+		if ! expect_error $name "$status":"$error_abort"; then
+			exit 1
+		fi
+	done
+
+	echo "$0: firmware upload cancellation works"
+	return 0
+}
+
+test_error_handling() {
+	local name=$1
+	local status
+	local error
+
+	for status in $progress_states; do
+		for error in $errors; do
+			inject_error $name $status $error
+
+			if ! await_idle $name; then
+				exit 1
+			fi
+
+			if ! expect_error $name "$status":"$error"; then
+				exit 1
+			fi
+
+		done
+	done
+	echo "$0: firmware upload error handling works"
+}
+
+test_fw_too_big() {
+	local name=$1
+	local fw_too_big=`random_firmware 512 5`
+	local expected="preparing:invalid-file-size"
+
+	upload_fw $name $fw_too_big
+	rm -f $fw_too_big
+
+	if ! await_idle $name; then
+		exit 1
+	fi
+
+	if ! expect_error $name $expected; then
+		exit 1
+	fi
+
+	echo "$0: oversized firmware error handling works"
+}
+
+echo -n "$fwname1" > "$DIR"/upload_register
+echo -n "$fwname2" > "$DIR"/upload_register
+echo -n "$fwname3" > "$DIR"/upload_register
+
+test_upload_cancel $fwname1
+test_error_handling $fwname1
+test_fw_too_big $fwname1
+
+fw_file1=`random_firmware 512 4`
+fw_file2=`random_firmware 512 3`
+fw_file3=`random_firmware 512 2`
+
+upload_fw $fwname1 $fw_file1
+upload_fw $fwname2 $fw_file2
+upload_fw $fwname3 $fw_file3
+
+verify_fw ${fwname1} ${fw_file1}
+verify_fw ${fwname2} ${fw_file2}
+verify_fw ${fwname3} ${fw_file3}
+
+echo -n "$fwname1" > "$DIR"/upload_unregister
+echo -n "$fwname2" > "$DIR"/upload_unregister
+echo -n "$fwname3" > "$DIR"/upload_unregister
+
+exit 0