Revert "USB: misc: Add onboard_usb_hub driver"

This reverts commit b4e326165e21d6a11483f6a4de2174b933413554 as the
patch series is causing build issues in linux-next at the moment.

Cc: Matthias Kaehlcke <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/ABI/testing/sysfs-bus-platform-onboard-usb-hub

···
-What:		/sys/bus/platform/devices/<dev>/always_powered_in_suspend
-Date:		March 2021
-KernelVersion:	5.13
-Contact:	Matthias Kaehlcke <[e-mail]>
-		[e-mail]
-Description:
-		(RW) Controls whether the USB hub remains always powered
-		during system suspend or not.

MAINTAINERS

···
 T:	git git://linuxtv.org/media_tree.git
 F:	drivers/media/i2c/ov9734.c
 
-ONBOARD USB HUB DRIVER
-M:	Matthias Kaehlcke <[e-mail]>
-L:	[e-mail]
-S:	Maintained
-F:	Documentation/devicetree/bindings/usb/onboard_usb_hub.yaml
-F:	drivers/usb/misc/onboard_usb_hub.c
-
 ONENAND FLASH DRIVER
 M:	Kyungmin Park <[e-mail]>
 L:	[e-mail]

drivers/usb/misc/Kconfig

···
 	  This option enables support for remapping some USB external
 	  signals, which are typically on dedicated pins on the chip,
 	  to any gpio.
-
-config USB_ONBOARD_HUB
-	tristate "Onboard USB hub support"
-	depends on OF || COMPILE_TEST
-	help
-	  Say Y here if you want to support discrete onboard USB hubs that
-	  don't require an additional control bus for initialization, but
-	  need some nontrivial form of initialization, such as enabling a
-	  power regulator. An example for such a hub is the Realtek
-	  RTS5411.
-
-	  The driver can be configured to turn off the power of the hub
-	  during system suspend. This may reduce power consumption while
-	  the system is suspended.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called onboard_usb_hub.

drivers/usb/misc/Makefile

···
 obj-$(CONFIG_USB_SISUSBVGA)		+= sisusbvga/
 obj-$(CONFIG_USB_LINK_LAYER_TEST)	+= lvstest.o
 obj-$(CONFIG_BRCM_USB_PINMAP)		+= brcmstb-usb-pinmap.o
-obj-$(CONFIG_USB_ONBOARD_HUB)		+= onboard_usb_hub.o

drivers/usb/misc/onboard_usb_hub.c

···
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- *  Driver for onboard USB hubs
- *
- * Copyright (c) 2020, Google LLC
- */
-
-#include <linux/device.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/list.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/of.h>
-#include <linux/of_platform.h>
-#include <linux/platform_device.h>
-#include <linux/regulator/consumer.h>
-#include <linux/suspend.h>
-#include <linux/sysfs.h>
-#include <linux/usb.h>
-#include <linux/usb/hcd.h>
-#include <linux/usb/of.h>
-#include <linux/usb/onboard_hub.h>
-
-static struct usb_device_driver onboard_hub_usbdev_driver;
-
-/************************** Platform driver **************************/
-
-struct udev_node {
-	struct usb_device *udev;
-	struct list_head list;
-};
-
-struct onboard_hub {
-	struct regulator *vdd;
-	struct device *dev;
-	bool always_powered_in_suspend;
-	bool is_powered_on;
-	bool going_away;
-	struct list_head udev_list;
-	struct mutex lock;
-};
-
-static int onboard_hub_power_on(struct onboard_hub *hub)
-{
-	int err;
-
-	err = regulator_enable(hub->vdd);
-	if (err) {
-		dev_err(hub->dev, "failed to enable regulator: %d\n", err);
-		return err;
-	}
-
-	hub->is_powered_on = true;
-
-	return 0;
-}
-
-static int onboard_hub_power_off(struct onboard_hub *hub)
-{
-	int err;
-
-	err = regulator_disable(hub->vdd);
-	if (err) {
-		dev_err(hub->dev, "failed to disable regulator: %d\n", err);
-		return err;
-	}
-
-	hub->is_powered_on = false;
-
-	return 0;
-}
-
-static int __maybe_unused onboard_hub_suspend(struct device *dev)
-{
-	struct onboard_hub *hub = dev_get_drvdata(dev);
-	struct udev_node *node;
-	bool power_off;
-	int rc = 0;
-
-	if (hub->always_powered_in_suspend)
-		return 0;
-
-	power_off = true;
-
-	mutex_lock(&hub->lock);
-
-	list_for_each_entry(node, &hub->udev_list, list) {
-		if (!device_may_wakeup(node->udev->bus->controller))
-			continue;
-
-		if (usb_wakeup_enabled_descendants(node->udev)) {
-			power_off = false;
-			break;
-		}
-	}
-
-	mutex_unlock(&hub->lock);
-
-	if (power_off)
-		rc = onboard_hub_power_off(hub);
-
-	return rc;
-}
-
-static int __maybe_unused onboard_hub_resume(struct device *dev)
-{
-	struct onboard_hub *hub = dev_get_drvdata(dev);
-	int rc = 0;
-
-	if (!hub->is_powered_on)
-		rc = onboard_hub_power_on(hub);
-
-	return rc;
-}
-
-static int onboard_hub_add_usbdev(struct onboard_hub *hub, struct usb_device *udev)
-{
-	struct udev_node *node;
-	char link_name[64];
-	int ret = 0;
-
-	mutex_lock(&hub->lock);
-
-	if (hub->going_away) {
-		ret = -EINVAL;
-		goto unlock;
-	}
-
-	node = devm_kzalloc(hub->dev, sizeof(*node), GFP_KERNEL);
-	if (!node) {
-		ret = -ENOMEM;
-		goto unlock;
-	}
-
-	node->udev = udev;
-
-	list_add(&node->list, &hub->udev_list);
-
-	snprintf(link_name, sizeof(link_name), "usb_dev.%s", dev_name(&udev->dev));
-	WARN_ON(sysfs_create_link(&hub->dev->kobj, &udev->dev.kobj, link_name));
-
-unlock:
-	mutex_unlock(&hub->lock);
-
-	return ret;
-}
-
-static void onboard_hub_remove_usbdev(struct onboard_hub *hub, struct usb_device *udev)
-{
-	struct udev_node *node;
-	char link_name[64];
-
-	snprintf(link_name, sizeof(link_name), "usb_dev.%s", dev_name(&udev->dev));
-	sysfs_remove_link(&hub->dev->kobj, link_name);
-
-	mutex_lock(&hub->lock);
-
-	list_for_each_entry(node, &hub->udev_list, list) {
-		if (node->udev == udev) {
-			list_del(&node->list);
-			break;
-		}
-	}
-
-	mutex_unlock(&hub->lock);
-}
-
-static ssize_t always_powered_in_suspend_show(struct device *dev, struct device_attribute *attr,
-			   char *buf)
-{
-	struct onboard_hub *hub = dev_get_drvdata(dev);
-
-	return sysfs_emit(buf, "%d\n", hub->always_powered_in_suspend);
-}
-
-static ssize_t always_powered_in_suspend_store(struct device *dev, struct device_attribute *attr,
-			    const char *buf, size_t count)
-{
-	struct onboard_hub *hub = dev_get_drvdata(dev);
-	bool val;
-	int ret;
-
-	ret = kstrtobool(buf, &val);
-	if (ret < 0)
-		return ret;
-
-	hub->always_powered_in_suspend = val;
-
-	return count;
-}
-static DEVICE_ATTR_RW(always_powered_in_suspend);
-
-static struct attribute *onboard_hub_attrs[] = {
-	&dev_attr_always_powered_in_suspend.attr,
-	NULL,
-};
-ATTRIBUTE_GROUPS(onboard_hub);
-
-static int onboard_hub_probe(struct platform_device *pdev)
-{
-	struct device *dev = &pdev->dev;
-	struct onboard_hub *hub;
-	int err;
-
-	hub = devm_kzalloc(dev, sizeof(*hub), GFP_KERNEL);
-	if (!hub)
-		return -ENOMEM;
-
-	hub->vdd = devm_regulator_get(dev, "vdd");
-	if (IS_ERR(hub->vdd))
-		return PTR_ERR(hub->vdd);
-
-	hub->dev = dev;
-	mutex_init(&hub->lock);
-	INIT_LIST_HEAD(&hub->udev_list);
-
-	dev_set_drvdata(dev, hub);
-
-	err = onboard_hub_power_on(hub);
-	if (err)
-		return err;
-
-	/*
-	 * The USB driver might have been detached from the USB devices by
-	 * onboard_hub_remove(), make sure to re-attach it if needed.
-	 */
-	err = driver_attach(&onboard_hub_usbdev_driver.drvwrap.driver);
-	if (err) {
-		onboard_hub_power_off(hub);
-		return err;
-	}
-
-	return 0;
-}
-
-static int onboard_hub_remove(struct platform_device *pdev)
-{
-	struct onboard_hub *hub = dev_get_drvdata(&pdev->dev);
-	struct udev_node *node;
-	struct usb_device *udev;
-
-	hub->going_away = true;
-
-	mutex_lock(&hub->lock);
-
-	/* unbind the USB devices to avoid dangling references to this device */
-	while (!list_empty(&hub->udev_list)) {
-		node = list_first_entry(&hub->udev_list, struct udev_node, list);
-		udev = node->udev;
-
-		/*
-		 * Unbinding the driver will call onboard_hub_remove_usbdev(),
-		 * which acquires hub->lock.  We must release the lock first.
-		 */
-		get_device(&udev->dev);
-		mutex_unlock(&hub->lock);
-		device_release_driver(&udev->dev);
-		put_device(&udev->dev);
-		mutex_lock(&hub->lock);
-	}
-
-	mutex_unlock(&hub->lock);
-
-	return onboard_hub_power_off(hub);
-}
-
-static const struct of_device_id onboard_hub_match[] = {
-	{ .compatible = "usbbda,411" },
-	{ .compatible = "usbbda,5411" },
-	{}
-};
-MODULE_DEVICE_TABLE(of, onboard_hub_match);
-
-static bool of_is_onboard_usb_hub(const struct device_node *np)
-{
-	return !!of_match_node(onboard_hub_match, np);
-}
-
-static const struct dev_pm_ops __maybe_unused onboard_hub_pm_ops = {
-	SET_LATE_SYSTEM_SLEEP_PM_OPS(onboard_hub_suspend, onboard_hub_resume)
-};
-
-static struct platform_driver onboard_hub_driver = {
-	.probe = onboard_hub_probe,
-	.remove = onboard_hub_remove,
-
-	.driver = {
-		.name = "onboard-usb-hub",
-		.of_match_table = onboard_hub_match,
-		.pm = pm_ptr(&onboard_hub_pm_ops),
-		.dev_groups = onboard_hub_groups,
-	},
-};
-
-/************************** USB driver **************************/
-
-#define VENDOR_ID_REALTEK	0x0bda
-
-/*
- * Returns the onboard_hub platform device that is associated with the USB
- * device passed as parameter.
- */
-static struct onboard_hub *_find_onboard_hub(struct device *dev)
-{
-	struct platform_device *pdev;
-	struct device_node *np;
-	phandle ph;
-
-	pdev = of_find_device_by_node(dev->of_node);
-	if (!pdev) {
-		if (of_property_read_u32(dev->of_node, "companion-hub", &ph)) {
-			dev_err(dev, "failed to read 'companion-hub' property\n");
-			return ERR_PTR(-EINVAL);
-		}
-
-		np = of_find_node_by_phandle(ph);
-		if (!np) {
-			dev_err(dev, "failed to find device node for companion hub\n");
-			return ERR_PTR(-EINVAL);
-		}
-
-		pdev = of_find_device_by_node(np);
-		of_node_put(np);
-
-		if (!pdev)
-			return ERR_PTR(-EPROBE_DEFER);
-	}
-
-	put_device(&pdev->dev);
-
-	return dev_get_drvdata(&pdev->dev);
-}
-
-static int onboard_hub_usbdev_probe(struct usb_device *udev)
-{
-	struct device *dev = &udev->dev;
-	struct onboard_hub *hub;
-	int err;
-
-	/* ignore supported hubs without device tree node */
-	if (!dev->of_node)
-		return -ENODEV;
-
-	hub = _find_onboard_hub(dev);
-	if (IS_ERR(hub))
-		return PTR_ERR(hub);
-
-	dev_set_drvdata(dev, hub);
-
-	err = onboard_hub_add_usbdev(hub, udev);
-	if (err)
-		return err;
-
-	err = sysfs_create_link(&udev->dev.kobj, &hub->dev->kobj, "onboard_hub_dev");
-	if (err)
-		dev_warn(&udev->dev, "failed to create symlink to platform device: %d\n", err);
-
-	return 0;
-}
-
-static void onboard_hub_usbdev_disconnect(struct usb_device *udev)
-{
-	struct onboard_hub *hub = dev_get_drvdata(&udev->dev);
-
-	sysfs_remove_link(&udev->dev.kobj, "onboard_hub_dev");
-
-	onboard_hub_remove_usbdev(hub, udev);
-}
-
-static const struct usb_device_id onboard_hub_id_table[] = {
-	{ USB_DEVICE(VENDOR_ID_REALTEK, 0x0411) }, /* RTS5411 USB 3.0 */
-	{ USB_DEVICE(VENDOR_ID_REALTEK, 0x5411) }, /* RTS5411 USB 2.0 */
-	{},
-};
-
-MODULE_DEVICE_TABLE(usb, onboard_hub_id_table);
-
-static struct usb_device_driver onboard_hub_usbdev_driver = {
-
-	.name = "onboard-usb-hub",
-	.probe = onboard_hub_usbdev_probe,
-	.disconnect = onboard_hub_usbdev_disconnect,
-	.generic_subclass = 1,
-	.supports_autosuspend =	1,
-	.id_table = onboard_hub_id_table,
-};
-
-/*** Helpers for creating/destroying platform devices for onboard hubs ***/
-
-struct pdev_list_entry {
-	struct platform_device *pdev;
-	struct list_head node;
-};
-
-/*
- * Creates a platform device for each supported onboard hub that is connected to
- * the given parent hub. To keep track of the platform devices they are added to
- * a list that is owned by the parent hub.
- */
-void onboard_hub_create_pdevs(struct usb_device *parent_hub, struct list_head *pdev_list)
-{
-	int i;
-	phandle ph;
-	struct device_node *np, *npc;
-	struct platform_device *pdev;
-	struct pdev_list_entry *pdle;
-
-	for (i = 1; i <= parent_hub->maxchild; i++) {
-		np = usb_of_get_device_node(parent_hub, i);
-		if (!np)
-			continue;
-
-		if (!of_is_onboard_usb_hub(np))
-			goto node_put;
-
-		if (of_property_read_u32(np, "companion-hub", &ph))
-			goto node_put;
-
-		npc = of_find_node_by_phandle(ph);
-		if (!npc)
-			goto node_put;
-
-		pdev = of_find_device_by_node(npc);
-		of_node_put(npc);
-
-		if (pdev) {
-			/* the companion hub already has a platform device, nothing to do here */
-			put_device(&pdev->dev);
-			goto node_put;
-		}
-
-		pdev = of_platform_device_create(np, NULL, &parent_hub->dev);
-		if (pdev) {
-			pdle = kzalloc(sizeof(*pdle), GFP_KERNEL);
-			if (!pdle)
-				goto node_put;
-
-			INIT_LIST_HEAD(&pdle->node);
-
-			pdle->pdev = pdev;
-			list_add(&pdle->node, pdev_list);
-		} else {
-			dev_err(&parent_hub->dev,
-				"failed to create platform device for onboard hub '%s'\n",
-				of_node_full_name(np));
-		}
-
-node_put:
-		of_node_put(np);
-	}
-}
-EXPORT_SYMBOL_GPL(onboard_hub_create_pdevs);
-
-/*
- * Destroys the platform devices in the given list and frees the memory associated
- * with the list entry.
- */
-void onboard_hub_destroy_pdevs(struct list_head *pdev_list)
-{
-	struct pdev_list_entry *pdle, *tmp;
-
-	list_for_each_entry_safe(pdle, tmp, pdev_list, node) {
-		of_platform_device_destroy(&pdle->pdev->dev, NULL);
-		kfree(pdle);
-	}
-}
-EXPORT_SYMBOL_GPL(onboard_hub_destroy_pdevs);
-
-/************************** Driver (de)registration **************************/
-
-static int __init onboard_hub_init(void)
-{
-	int ret;
-
-	ret = platform_driver_register(&onboard_hub_driver);
-	if (ret)
-		return ret;
-
-	ret = usb_register_device_driver(&onboard_hub_usbdev_driver, THIS_MODULE);
-	if (ret)
-		platform_driver_unregister(&onboard_hub_driver);
-
-	return ret;
-}
-module_init(onboard_hub_init);
-
-static void __exit onboard_hub_exit(void)
-{
-	usb_deregister_device_driver(&onboard_hub_usbdev_driver);
-	platform_driver_unregister(&onboard_hub_driver);
-}
-module_exit(onboard_hub_exit);
-
-MODULE_AUTHOR("Matthias Kaehlcke <[e-mail]>");
-MODULE_DESCRIPTION("Driver for discrete onboard USB hubs");
-MODULE_LICENSE("GPL v2");

include/linux/usb/onboard_hub.h

···
-/* SPDX-License-Identifier: GPL-2.0 */
-
-#ifndef __LINUX_USB_ONBOARD_HUB_H
-#define __LINUX_USB_ONBOARD_HUB_H
-
-struct usb_device;
-struct list_head;
-
-#if IS_ENABLED(CONFIG_USB_ONBOARD_HUB)
-void onboard_hub_create_pdevs(struct usb_device *parent_hub, struct list_head *pdev_list);
-void onboard_hub_destroy_pdevs(struct list_head *pdev_list);
-#else
-static inline void onboard_hub_create_pdevs(struct usb_device *parent_hub,
-					    struct list_head *pdev_list) {}
-static inline void onboard_hub_destroy_pdevs(struct list_head *pdev_list) {}
-#endif
-
-#endif /* __LINUX_USB_ONBOARD_HUB_H */