Merge branch 'device-properties'

* device-properties:
ACPI / property: Fix subnode lookup scope for data-only subnodes
acpi-dma: Add support for "dma-names" device property
device property: Add fwnode_property_match_string()
ACPI / property: Extend device_get_next_child_node() to data-only nodes
ACPI / gpio: Split acpi_get_gpiod_by_index()
ACPI / property: Extend fwnode_property_* to data-only subnodes
ACPI / property: Expose data-only subnodes via sysfs
ACPI / property: Add support for data-only subnodes
ACPI / property: Add routine for extraction of _DSD properties

drivers/acpi/device_sysfs.c

···
 
 #include "internal.h"
 
+static ssize_t acpi_object_path(acpi_handle handle, char *buf)
+{
+	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
+	int result;
+
+	result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path);
+	if (result)
+		return result;
+
+	result = sprintf(buf, "%s\n", (char*)path.pointer);
+	kfree(path.pointer);
+	return result;
+}
+
+struct acpi_data_node_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct acpi_data_node *, char *);
+	ssize_t (*store)(struct acpi_data_node *, const char *, size_t count);
+};
+
+#define DATA_NODE_ATTR(_name)			\
+	static struct acpi_data_node_attr data_node_##_name =	\
+		__ATTR(_name, 0444, data_node_show_##_name, NULL)
+
+static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf)
+{
+	return acpi_object_path(dn->handle, buf);
+}
+
+DATA_NODE_ATTR(path);
+
+static struct attribute *acpi_data_node_default_attrs[] = {
+	&data_node_path.attr,
+	NULL
+};
+
+#define to_data_node(k) container_of(k, struct acpi_data_node, kobj)
+#define to_attr(a) container_of(a, struct acpi_data_node_attr, attr)
+
+static ssize_t acpi_data_node_attr_show(struct kobject *kobj,
+					struct attribute *attr, char *buf)
+{
+	struct acpi_data_node *dn = to_data_node(kobj);
+	struct acpi_data_node_attr *dn_attr = to_attr(attr);
+
+	return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO;
+}
+
+static const struct sysfs_ops acpi_data_node_sysfs_ops = {
+	.show	= acpi_data_node_attr_show,
+};
+
+static void acpi_data_node_release(struct kobject *kobj)
+{
+	struct acpi_data_node *dn = to_data_node(kobj);
+	complete(&dn->kobj_done);
+}
+
+static struct kobj_type acpi_data_node_ktype = {
+	.sysfs_ops = &acpi_data_node_sysfs_ops,
+	.default_attrs = acpi_data_node_default_attrs,
+	.release = acpi_data_node_release,
+};
+
+static void acpi_expose_nondev_subnodes(struct kobject *kobj,
+					struct acpi_device_data *data)
+{
+	struct list_head *list = &data->subnodes;
+	struct acpi_data_node *dn;
+
+	if (list_empty(list))
+		return;
+
+	list_for_each_entry(dn, list, sibling) {
+		int ret;
+
+		init_completion(&dn->kobj_done);
+		ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype,
+					   kobj, dn->name);
+		if (ret)
+			acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret);
+		else
+			acpi_expose_nondev_subnodes(&dn->kobj, &dn->data);
+	}
+}
+
+static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
+{
+	struct list_head *list = &data->subnodes;
+	struct acpi_data_node *dn;
+
+	if (list_empty(list))
+		return;
+
+	list_for_each_entry_reverse(dn, list, sibling) {
+		acpi_hide_nondev_subnodes(&dn->data);
+		kobject_put(&dn->kobj);
+	}
+}
+
 /**
  * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent
  * @acpi_dev: ACPI device object.
···
 }
 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 
-static ssize_t
-acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
+static ssize_t acpi_device_path_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
 	struct acpi_device *acpi_dev = to_acpi_device(dev);
-	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
-	int result;
 
-	result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
-	if (result)
-		goto end;
-
-	result = sprintf(buf, "%s\n", (char*)path.pointer);
-	kfree(path.pointer);
-end:
-	return result;
+	return acpi_object_path(acpi_dev->handle, buf);
 }
 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 
···
 						    &dev_attr_real_power_state);
 	}
 
+	acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);
+
 end:
 	return result;
 }
···
  */
 void acpi_device_remove_files(struct acpi_device *dev)
 {
+	acpi_hide_nondev_subnodes(&dev->data);
+
 	if (dev->flags.power_manageable) {
 		device_remove_file(&dev->dev, &dev_attr_power_state);
 		if (dev->power.flags.power_resources)

drivers/acpi/property.c

···
 
 #include "internal.h"
 
+static int acpi_data_get_property_array(struct acpi_device_data *data,
+					const char *name,
+					acpi_object_type type,
+					const union acpi_object **obj);
+
 /* ACPI _DSD device properties UUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
 static const u8 prp_uuid[16] = {
 	0x14, 0xd8, 0xff, 0xda, 0xba, 0x6e, 0x8c, 0x4d,
 	0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01
 };
+/* ACPI _DSD data subnodes UUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
+static const u8 ads_uuid[16] = {
+	0xe6, 0xe3, 0xb8, 0xdb, 0x86, 0x58, 0xa6, 0x4b,
+	0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b
+};
+
+static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
+					   const union acpi_object *desc,
+					   struct acpi_device_data *data);
+static bool acpi_extract_properties(const union acpi_object *desc,
+				    struct acpi_device_data *data);
+
+static bool acpi_nondev_subnode_ok(acpi_handle scope,
+				   const union acpi_object *link,
+				   struct list_head *list)
+{
+	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+	struct acpi_data_node *dn;
+	acpi_handle handle;
+	acpi_status status;
+
+	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
+	if (!dn)
+		return false;
+
+	dn->name = link->package.elements[0].string.pointer;
+	dn->fwnode.type = FWNODE_ACPI_DATA;
+	INIT_LIST_HEAD(&dn->data.subnodes);
+
+	status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
+				 &handle);
+	if (ACPI_FAILURE(status))
+		goto fail;
+
+	status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
+					    ACPI_TYPE_PACKAGE);
+	if (ACPI_FAILURE(status))
+		goto fail;
+
+	if (acpi_extract_properties(buf.pointer, &dn->data))
+		dn->handle = handle;
+
+	/*
+	 * The scope for the subnode object lookup is the one of the namespace
+	 * node (device) containing the object that has returned the package.
+	 * That is, it's the scope of that object's parent.
+	 */
+	status = acpi_get_parent(handle, &scope);
+	if (ACPI_SUCCESS(status)
+	    && acpi_enumerate_nondev_subnodes(scope, buf.pointer, &dn->data))
+		dn->handle = handle;
+
+	if (dn->handle) {
+		dn->data.pointer = buf.pointer;
+		list_add_tail(&dn->sibling, list);
+		return true;
+	}
+
+	acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
+
+ fail:
+	ACPI_FREE(buf.pointer);
+	kfree(dn);
+	return false;
+}
+
+static int acpi_add_nondev_subnodes(acpi_handle scope,
+				    const union acpi_object *links,
+				    struct list_head *list)
+{
+	bool ret = false;
+	int i;
+
+	for (i = 0; i < links->package.count; i++) {
+		const union acpi_object *link;
+
+		link = &links->package.elements[i];
+		/* Only two elements allowed, both must be strings. */
+		if (link->package.count == 2
+		    && link->package.elements[0].type == ACPI_TYPE_STRING
+		    && link->package.elements[1].type == ACPI_TYPE_STRING
+		    && acpi_nondev_subnode_ok(scope, link, list))
+			ret = true;
+	}
+
+	return ret;
+}
+
+static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
+					   const union acpi_object *desc,
+					   struct acpi_device_data *data)
+{
+	int i;
+
+	/* Look for the ACPI data subnodes UUID. */
+	for (i = 0; i < desc->package.count; i += 2) {
+		const union acpi_object *uuid, *links;
+
+		uuid = &desc->package.elements[i];
+		links = &desc->package.elements[i + 1];
+
+		/*
+		 * The first element must be a UUID and the second one must be
+		 * a package.
+		 */
+		if (uuid->type != ACPI_TYPE_BUFFER || uuid->buffer.length != 16
+		    || links->type != ACPI_TYPE_PACKAGE)
+			break;
+
+		if (memcmp(uuid->buffer.pointer, ads_uuid, sizeof(ads_uuid)))
+			continue;
+
+		return acpi_add_nondev_subnodes(scope, links, &data->subnodes);
+	}
+
+	return false;
+}
 
 static bool acpi_property_value_ok(const union acpi_object *value)
 {
···
 	const union acpi_object *of_compatible;
 	int ret;
 
-	ret = acpi_dev_get_property_array(adev, "compatible", ACPI_TYPE_STRING,
-					  &of_compatible);
+	ret = acpi_data_get_property_array(&adev->data, "compatible",
+					   ACPI_TYPE_STRING, &of_compatible);
 	if (ret) {
 		ret = acpi_dev_get_property(adev, "compatible",
 					    ACPI_TYPE_STRING, &of_compatible);
···
 	adev->flags.of_compatible_ok = 1;
 }
 
-void acpi_init_properties(struct acpi_device *adev)
+static bool acpi_extract_properties(const union acpi_object *desc,
+				    struct acpi_device_data *data)
 {
-	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
-	bool acpi_of = false;
-	struct acpi_hardware_id *hwid;
-	const union acpi_object *desc;
-	acpi_status status;
 	int i;
 
-	/*
-	 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
-	 * Device Tree compatible properties for this device.
-	 */
-	list_for_each_entry(hwid, &adev->pnp.ids, list) {
-		if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
-			acpi_of = true;
-			break;
-		}
-	}
-
-	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
-					    ACPI_TYPE_PACKAGE);
-	if (ACPI_FAILURE(status))
-		goto out;
-
-	desc = buf.pointer;
 	if (desc->package.count % 2)
-		goto fail;
+		return false;
 
 	/* Look for the device properties UUID. */
 	for (i = 0; i < desc->package.count; i += 2) {
···
 		if (!acpi_properties_format_valid(properties))
 			break;
 
-		adev->data.pointer = buf.pointer;
-		adev->data.properties = properties;
-
-		if (acpi_of)
-			acpi_init_of_compatible(adev);
-
-		goto out;
+		data->properties = properties;
+		return true;
 	}
 
- fail:
-	dev_dbg(&adev->dev, "Returned _DSD data is not valid, skipping\n");
-	ACPI_FREE(buf.pointer);
+	return false;
+}
+
+void acpi_init_properties(struct acpi_device *adev)
+{
+	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+	struct acpi_hardware_id *hwid;
+	acpi_status status;
+	bool acpi_of = false;
+
+	INIT_LIST_HEAD(&adev->data.subnodes);
+
+	/*
+	 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
+	 * Device Tree compatible properties for this device.
+	 */
+	list_for_each_entry(hwid, &adev->pnp.ids, list) {
+		if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
+			acpi_of = true;
+			break;
+		}
+	}
+
+	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
+					    ACPI_TYPE_PACKAGE);
+	if (ACPI_FAILURE(status))
+		goto out;
+
+	if (acpi_extract_properties(buf.pointer, &adev->data)) {
+		adev->data.pointer = buf.pointer;
+		if (acpi_of)
+			acpi_init_of_compatible(adev);
+	}
+	if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer, &adev->data))
+		adev->data.pointer = buf.pointer;
+
+	if (!adev->data.pointer) {
+		acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
+		ACPI_FREE(buf.pointer);
+	}
 
  out:
 	if (acpi_of && !adev->flags.of_compatible_ok)
···
 			 ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
 }
 
+static void acpi_destroy_nondev_subnodes(struct list_head *list)
+{
+	struct acpi_data_node *dn, *next;
+
+	if (list_empty(list))
+		return;
+
+	list_for_each_entry_safe_reverse(dn, next, list, sibling) {
+		acpi_destroy_nondev_subnodes(&dn->data.subnodes);
+		wait_for_completion(&dn->kobj_done);
+		list_del(&dn->sibling);
+		ACPI_FREE((void *)dn->data.pointer);
+		kfree(dn);
+	}
+}
+
 void acpi_free_properties(struct acpi_device *adev)
 {
+	acpi_destroy_nondev_subnodes(&adev->data.subnodes);
 	ACPI_FREE((void *)adev->data.pointer);
 	adev->data.of_compatible = NULL;
 	adev->data.pointer = NULL;
···
 }
 
 /**
- * acpi_dev_get_property - return an ACPI property with given name
- * @adev: ACPI device to get property
+ * acpi_data_get_property - return an ACPI property with given name
+ * @data: ACPI device deta object to get the property from
  * @name: Name of the property
  * @type: Expected property type
  * @obj: Location to store the property value (if not %NULL)
···
  * object at the location pointed to by @obj if found.
  *
  * Callers must not attempt to free the returned objects.  These objects will be
- * freed by the ACPI core automatically during the removal of @adev.
+ * freed by the ACPI core automatically during the removal of @data.
  *
  * Return: %0 if property with @name has been found (success),
  *         %-EINVAL if the arguments are invalid,
  *         %-ENODATA if the property doesn't exist,
  *         %-EPROTO if the property value type doesn't match @type.
  */
-int acpi_dev_get_property(struct acpi_device *adev, const char *name,
-			  acpi_object_type type, const union acpi_object **obj)
+static int acpi_data_get_property(struct acpi_device_data *data,
+				  const char *name, acpi_object_type type,
+				  const union acpi_object **obj)
 {
 	const union acpi_object *properties;
 	int i;
 
-	if (!adev || !name)
+	if (!data || !name)
 		return -EINVAL;
 
-	if (!adev->data.pointer || !adev->data.properties)
+	if (!data->pointer || !data->properties)
 		return -ENODATA;
 
-	properties = adev->data.properties;
+	properties = data->properties;
 	for (i = 0; i < properties->package.count; i++) {
 		const union acpi_object *propname, *propvalue;
 		const union acpi_object *property;
···
 	}
 	return -ENODATA;
 }
-EXPORT_SYMBOL_GPL(acpi_dev_get_property);
 
 /**
- * acpi_dev_get_property_array - return an ACPI array property with given name
- * @adev: ACPI device to get property
+ * acpi_dev_get_property - return an ACPI property with given name.
+ * @adev: ACPI device to get the property from.
+ * @name: Name of the property.
+ * @type: Expected property type.
+ * @obj: Location to store the property value (if not %NULL).
+ */
+int acpi_dev_get_property(struct acpi_device *adev, const char *name,
+			  acpi_object_type type, const union acpi_object **obj)
+{
+	return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_property);
+
+static struct acpi_device_data *acpi_device_data_of_node(struct fwnode_handle *fwnode)
+{
+	if (fwnode->type == FWNODE_ACPI) {
+		struct acpi_device *adev = to_acpi_device_node(fwnode);
+		return &adev->data;
+	} else if (fwnode->type == FWNODE_ACPI_DATA) {
+		struct acpi_data_node *dn = to_acpi_data_node(fwnode);
+		return &dn->data;
+	}
+	return NULL;
+}
+
+/**
+ * acpi_node_prop_get - return an ACPI property with given name.
+ * @fwnode: Firmware node to get the property from.
+ * @propname: Name of the property.
+ * @valptr: Location to store a pointer to the property value (if not %NULL).
+ */
+int acpi_node_prop_get(struct fwnode_handle *fwnode, const char *propname,
+		       void **valptr)
+{
+	return acpi_data_get_property(acpi_device_data_of_node(fwnode),
+				      propname, ACPI_TYPE_ANY,
+				      (const union acpi_object **)valptr);
+}
+
+/**
+ * acpi_data_get_property_array - return an ACPI array property with given name
+ * @adev: ACPI data object to get the property from
  * @name: Name of the property
  * @type: Expected type of array elements
  * @obj: Location to store a pointer to the property value (if not NULL)
···
  * ACPI object at the location pointed to by @obj if found.
  *
  * Callers must not attempt to free the returned objects.  Those objects will be
- * freed by the ACPI core automatically during the removal of @adev.
+ * freed by the ACPI core automatically during the removal of @data.
  *
  * Return: %0 if array property (package) with @name has been found (success),
  *         %-EINVAL if the arguments are invalid,
···
  *         %-EPROTO if the property is not a package or the type of its elements
  *           doesn't match @type.
  */
-int acpi_dev_get_property_array(struct acpi_device *adev, const char *name,
-				acpi_object_type type,
-				const union acpi_object **obj)
+static int acpi_data_get_property_array(struct acpi_device_data *data,
+					const char *name,
+					acpi_object_type type,
+					const union acpi_object **obj)
 {
 	const union acpi_object *prop;
 	int ret, i;
 
-	ret = acpi_dev_get_property(adev, name, ACPI_TYPE_PACKAGE, &prop);
+	ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
 	if (ret)
 		return ret;
 
···
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(acpi_dev_get_property_array);
 
 /**
- * acpi_dev_get_property_reference - returns handle to the referenced object
- * @adev: ACPI device to get property
- * @name: Name of the property
+ * acpi_data_get_property_reference - returns handle to the referenced object
+ * @data: ACPI device data object containing the property
+ * @propname: Name of the property
  * @index: Index of the reference to return
  * @args: Location to store the returned reference with optional arguments
  *
···
  *
  * Return: %0 on success, negative error code on failure.
  */
-int acpi_dev_get_property_reference(struct acpi_device *adev,
-				    const char *name, size_t index,
-				    struct acpi_reference_args *args)
+static int acpi_data_get_property_reference(struct acpi_device_data *data,
+					    const char *propname, size_t index,
+					    struct acpi_reference_args *args)
 {
 	const union acpi_object *element, *end;
 	const union acpi_object *obj;
 	struct acpi_device *device;
 	int ret, idx = 0;
 
-	ret = acpi_dev_get_property(adev, name, ACPI_TYPE_ANY, &obj);
+	ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
 	if (ret)
 		return ret;
 
···
 
 	return -EPROTO;
 }
-EXPORT_SYMBOL_GPL(acpi_dev_get_property_reference);
 
-int acpi_dev_prop_get(struct acpi_device *adev, const char *propname,
-		      void **valptr)
+/**
+ * acpi_node_get_property_reference - get a handle to the referenced object.
+ * @fwnode: Firmware node to get the property from.
+ * @propname: Name of the property.
+ * @index: Index of the reference to return.
+ * @args: Location to store the returned reference with optional arguments.
+ */
+int acpi_node_get_property_reference(struct fwnode_handle *fwnode,
+				     const char *name, size_t index,
+				     struct acpi_reference_args *args)
 {
-	return acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
-				     (const union acpi_object **)valptr);
-}
+	struct acpi_device_data *data = acpi_device_data_of_node(fwnode);
 
-int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
-			      enum dev_prop_type proptype, void *val)
+	return data ? acpi_data_get_property_reference(data, name, index, args) : -EINVAL;
+}
+EXPORT_SYMBOL_GPL(acpi_node_get_property_reference);
+
+static int acpi_data_prop_read_single(struct acpi_device_data *data,
+				      const char *propname,
+				      enum dev_prop_type proptype, void *val)
 {
 	const union acpi_object *obj;
 	int ret;
···
 		return -EINVAL;
 
 	if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
-		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_INTEGER, &obj);
+		ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
 		if (ret)
 			return ret;
 
···
 			break;
 		}
 	} else if (proptype == DEV_PROP_STRING) {
-		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_STRING, &obj);
+		ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
 		if (ret)
 			return ret;
 
···
 		ret = -EINVAL;
 	}
 	return ret;
+}
+
+int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
+			      enum dev_prop_type proptype, void *val)
+{
+	return adev ? acpi_data_prop_read_single(&adev->data, propname, proptype, val) : -EINVAL;
 }
 
 static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
···
 	return 0;
 }
 
-int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
-		       enum dev_prop_type proptype, void *val, size_t nval)
+static int acpi_data_prop_read(struct acpi_device_data *data,
+			       const char *propname,
+			       enum dev_prop_type proptype,
+			       void *val, size_t nval)
 {
 	const union acpi_object *obj;
 	const union acpi_object *items;
 	int ret;
 
 	if (val && nval == 1) {
-		ret = acpi_dev_prop_read_single(adev, propname, proptype, val);
+		ret = acpi_data_prop_read_single(data, propname, proptype, val);
 		if (!ret)
 			return ret;
 	}
 
-	ret = acpi_dev_get_property_array(adev, propname, ACPI_TYPE_ANY, &obj);
+	ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
 	if (ret)
 		return ret;
 
···
 		break;
 	}
 	return ret;
+}
+
+int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
+		       enum dev_prop_type proptype, void *val, size_t nval)
+{
+	return adev ? acpi_data_prop_read(&adev->data, propname, proptype, val, nval) : -EINVAL;
+}
+
+/**
+ * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
+ * @fwnode: Firmware node to get the property from.
+ * @propname: Name of the property.
+ * @proptype: Expected property type.
+ * @val: Location to store the property value (if not %NULL).
+ * @nval: Size of the array pointed to by @val.
+ *
+ * If @val is %NULL, return the number of array elements comprising the value
+ * of the property.  Otherwise, read at most @nval values to the array at the
+ * location pointed to by @val.
+ */
+int acpi_node_prop_read(struct fwnode_handle *fwnode,  const char *propname,
+		        enum dev_prop_type proptype, void *val, size_t nval)
+{
+	return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
+				   propname, proptype, val, nval);
+}
+
+/**
+ * acpi_get_next_subnode - Return the next child node handle for a device.
+ * @dev: Device to find the next child node for.
+ * @child: Handle to one of the device's child nodes or a null handle.
+ */
+struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
+					    struct fwnode_handle *child)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	struct list_head *head, *next;
+
+	if (!adev)
+		return NULL;
+
+	if (!child || child->type == FWNODE_ACPI) {
+		head = &adev->children;
+		if (list_empty(head))
+			goto nondev;
+
+		if (child) {
+			adev = to_acpi_device_node(child);
+			next = adev->node.next;
+			if (next == head) {
+				child = NULL;
+				goto nondev;
+			}
+			adev = list_entry(next, struct acpi_device, node);
+		} else {
+			adev = list_first_entry(head, struct acpi_device, node);
+		}
+		return acpi_fwnode_handle(adev);
+	}
+
+ nondev:
+	if (!child || child->type == FWNODE_ACPI_DATA) {
+		struct acpi_data_node *dn;
+
+		head = &adev->data.subnodes;
+		if (list_empty(head))
+			return NULL;
+
+		if (child) {
+			dn = to_acpi_data_node(child);
+			next = dn->sibling.next;
+			if (next == head)
+				return NULL;
+
+			dn = list_entry(next, struct acpi_data_node, sibling);
+		} else {
+			dn = list_first_entry(head, struct acpi_data_node, sibling);
+		}
+		return &dn->fwnode;
+	}
+	return NULL;
 }

drivers/acpi/scan.c

···
 	return result;
 }
 
-struct acpi_device *acpi_get_next_child(struct device *dev,
-					struct acpi_device *child)
-{
-	struct acpi_device *adev = ACPI_COMPANION(dev);
-	struct list_head *head, *next;
-
-	if (!adev)
-		return NULL;
-
-	head = &adev->children;
-	if (list_empty(head))
-		return NULL;
-
-	if (!child)
-		return list_first_entry(head, struct acpi_device, node);
-
-	next = child->node.next;
-	return next == head ? NULL : list_entry(next, struct acpi_device, node);
-}
-
 /* --------------------------------------------------------------------------
                                  Device Enumeration
    -------------------------------------------------------------------------- */

drivers/base/property.c

···
 	if (is_of_node(fwnode))
 		return of_property_read_bool(to_of_node(fwnode), propname);
 	else if (is_acpi_node(fwnode))
-		return !acpi_dev_prop_get(to_acpi_node(fwnode), propname, NULL);
+		return !acpi_node_prop_get(fwnode, propname, NULL);
 
 	return !!pset_prop_get(to_pset(fwnode), propname);
 }
···
 }
 EXPORT_SYMBOL_GPL(device_property_read_string);
 
+/**
+ * device_property_match_string - find a string in an array and return index
+ * @dev: Device to get the property of
+ * @propname: Name of the property holding the array
+ * @string: String to look for
+ *
+ * Find a given string in a string array and if it is found return the
+ * index back.
+ *
+ * Return: %0 if the property was found (success),
+ *	   %-EINVAL if given arguments are not valid,
+ *	   %-ENODATA if the property does not have a value,
+ *	   %-EPROTO if the property is not an array of strings,
+ *	   %-ENXIO if no suitable firmware interface is present.
+ */
+int device_property_match_string(struct device *dev, const char *propname,
+				 const char *string)
+{
+	return fwnode_property_match_string(dev_fwnode(dev), propname, string);
+}
+EXPORT_SYMBOL_GPL(device_property_match_string);
+
 #define OF_DEV_PROP_READ_ARRAY(node, propname, type, val, nval) \
 	(val) ? of_property_read_##type##_array((node), (propname), (val), (nval)) \
 	      : of_property_count_elems_of_size((node), (propname), sizeof(type))
···
 		_ret_ = OF_DEV_PROP_READ_ARRAY(to_of_node(_fwnode_), _propname_, \
 					       _type_, _val_, _nval_); \
 	else if (is_acpi_node(_fwnode_)) \
-		_ret_ = acpi_dev_prop_read(to_acpi_node(_fwnode_), _propname_, \
-					   _proptype_, _val_, _nval_); \
+		_ret_ = acpi_node_prop_read(_fwnode_, _propname_, _proptype_, \
+					    _val_, _nval_); \
 	else if (is_pset(_fwnode_)) \
 		_ret_ = pset_prop_read_array(to_pset(_fwnode_), _propname_, \
 					     _proptype_, _val_, _nval_); \
···
 						      propname, val, nval) :
 			of_property_count_strings(to_of_node(fwnode), propname);
 	else if (is_acpi_node(fwnode))
-		return acpi_dev_prop_read(to_acpi_node(fwnode), propname,
-					  DEV_PROP_STRING, val, nval);
+		return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
+					   val, nval);
 	else if (is_pset(fwnode))
 		return pset_prop_read_array(to_pset(fwnode), propname,
 					    DEV_PROP_STRING, val, nval);
···
 	if (is_of_node(fwnode))
 		return of_property_read_string(to_of_node(fwnode), propname, val);
 	else if (is_acpi_node(fwnode))
-		return acpi_dev_prop_read(to_acpi_node(fwnode), propname,
-					  DEV_PROP_STRING, val, 1);
+		return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
+					   val, 1);
 
 	return pset_prop_read_array(to_pset(fwnode), propname,
 				    DEV_PROP_STRING, val, 1);
 }
 EXPORT_SYMBOL_GPL(fwnode_property_read_string);
+
+/**
+ * fwnode_property_match_string - find a string in an array and return index
+ * @fwnode: Firmware node to get the property of
+ * @propname: Name of the property holding the array
+ * @string: String to look for
+ *
+ * Find a given string in a string array and if it is found return the
+ * index back.
+ *
+ * Return: %0 if the property was found (success),
+ *	   %-EINVAL if given arguments are not valid,
+ *	   %-ENODATA if the property does not have a value,
+ *	   %-EPROTO if the property is not an array of strings,
+ *	   %-ENXIO if no suitable firmware interface is present.
+ */
+int fwnode_property_match_string(struct fwnode_handle *fwnode,
+	const char *propname, const char *string)
+{
+	const char **values;
+	int nval, ret, i;
+
+	nval = fwnode_property_read_string_array(fwnode, propname, NULL, 0);
+	if (nval < 0)
+		return nval;
+
+	values = kcalloc(nval, sizeof(*values), GFP_KERNEL);
+	if (!values)
+		return -ENOMEM;
+
+	ret = fwnode_property_read_string_array(fwnode, propname, values, nval);
+	if (ret < 0)
+		goto out;
+
+	ret = -ENODATA;
+	for (i = 0; i < nval; i++) {
+		if (!strcmp(values[i], string)) {
+			ret = i;
+			break;
+		}
+	}
+out:
+	kfree(values);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(fwnode_property_match_string);
 
 /**
  * device_get_next_child_node - Return the next child node handle for a device
···
 		if (node)
 			return &node->fwnode;
 	} else if (IS_ENABLED(CONFIG_ACPI)) {
-		struct acpi_device *node;
-
-		node = acpi_get_next_child(dev, to_acpi_node(child));
-		if (node)
-			return acpi_fwnode_handle(node);
+		return acpi_get_next_subnode(dev, child);
 	}
 	return NULL;
 }

drivers/dma/acpi-dma.c

···
 #include <linux/ioport.h>
 #include <linux/acpi.h>
 #include <linux/acpi_dma.h>
+#include <linux/property.h>
 
 static LIST_HEAD(acpi_dma_list);
 static DEFINE_MUTEX(acpi_dma_lock);
···
  * translate the names "tx" and "rx" here based on the most common case where
  * the first FixedDMA descriptor is TX and second is RX.
  *
+ * If the device has "dma-names" property the FixedDMA descriptor indices
+ * are retrieved based on those. Otherwise the function falls back using
+ * hardcoded indices.
+ *
  * Return:
  * Pointer to appropriate dma channel on success or an error pointer.
  */
 struct dma_chan *acpi_dma_request_slave_chan_by_name(struct device *dev,
 		const char *name)
 {
-	size_t index;
+	int index;
 
-	if (!strcmp(name, "tx"))
-		index = 0;
-	else if (!strcmp(name, "rx"))
-		index = 1;
-	else
-		return ERR_PTR(-ENODEV);
+	index = device_property_match_string(dev, "dma-names", name);
+	if (index < 0) {
+		if (!strcmp(name, "tx"))
+			index = 0;
+		else if (!strcmp(name, "rx"))
+			index = 1;
+		else
+			return ERR_PTR(-ENODEV);
+	}
 
+	dev_dbg(dev, "found DMA channel \"%s\" at index %d\n", name, index);
 	return acpi_dma_request_slave_chan_by_index(dev, index);
 }
 EXPORT_SYMBOL_GPL(acpi_dma_request_slave_chan_by_name);

drivers/gpio/gpiolib-acpi.c

···
 	struct acpi_gpio_info info;
 	int index;
 	int pin_index;
+	bool active_low;
+	struct acpi_device *adev;
 	struct gpio_desc *desc;
 	int n;
 };
···
 	return 1;
 }
 
+static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
+				     struct acpi_gpio_info *info)
+{
+	struct list_head res_list;
+	int ret;
+
+	INIT_LIST_HEAD(&res_list);
+
+	ret = acpi_dev_get_resources(lookup->adev, &res_list, acpi_find_gpio,
+				     lookup);
+	if (ret < 0)
+		return ret;
+
+	acpi_dev_free_resource_list(&res_list);
+
+	if (!lookup->desc)
+		return -ENOENT;
+
+	if (info) {
+		*info = lookup->info;
+		if (lookup->active_low)
+			info->active_low = lookup->active_low;
+	}
+	return 0;
+}
+
+static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
+				     const char *propname, int index,
+				     struct acpi_gpio_lookup *lookup)
+{
+	struct acpi_reference_args args;
+	int ret;
+
+	memset(&args, 0, sizeof(args));
+	ret = acpi_node_get_property_reference(fwnode, propname, index, &args);
+	if (ret) {
+		struct acpi_device *adev = to_acpi_device_node(fwnode);
+
+		if (!adev)
+			return ret;
+
+		if (!acpi_get_driver_gpio_data(adev, propname, index, &args))
+			return ret;
+	}
+	/*
+	 * The property was found and resolved, so need to lookup the GPIO based
+	 * on returned args.
+	 */
+	lookup->adev = args.adev;
+	if (args.nargs >= 2) {
+		lookup->index = args.args[0];
+		lookup->pin_index = args.args[1];
+		/* 3rd argument, if present is used to specify active_low. */
+		if (args.nargs >= 3)
+			lookup->active_low = !!args.args[2];
+	}
+	return 0;
+}
+
 /**
  * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
  * @adev: pointer to a ACPI device to get GPIO from
···
 					  struct acpi_gpio_info *info)
 {
 	struct acpi_gpio_lookup lookup;
-	struct list_head resource_list;
-	bool active_low = false;
 	int ret;
 
 	if (!adev)
···
 	lookup.index = index;
 
 	if (propname) {
-		struct acpi_reference_args args;
-
 		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
 
-		memset(&args, 0, sizeof(args));
-		ret = acpi_dev_get_property_reference(adev, propname,
-						      index, &args);
-		if (ret) {
-			bool found = acpi_get_driver_gpio_data(adev, propname,
-							       index, &args);
-			if (!found)
-				return ERR_PTR(ret);
-		}
+		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
+						propname, index, &lookup);
+		if (ret)
+			return ERR_PTR(ret);
 
-		/*
-		 * The property was found and resolved so need to
-		 * lookup the GPIO based on returned args instead.
-		 */
-		adev = args.adev;
-		if (args.nargs >= 2) {
-			lookup.index = args.args[0];
-			lookup.pin_index = args.args[1];
-			/*
-			 * 3rd argument, if present is used to
-			 * specify active_low.
-			 */
-			if (args.nargs >= 3)
-				active_low = !!args.args[2];
-		}
-
-		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %zd %llu %llu %llu\n",
-			dev_name(&adev->dev), args.nargs,
-			args.args[0], args.args[1], args.args[2]);
+		dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
+			dev_name(&lookup.adev->dev), lookup.index,
+			lookup.pin_index, lookup.active_low);
 	} else {
 		dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
+		lookup.adev = adev;
 	}
 
-	INIT_LIST_HEAD(&resource_list);
-	ret = acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio,
-				     &lookup);
-	if (ret < 0)
+	ret = acpi_gpio_resource_lookup(&lookup, info);
+	return ret ? ERR_PTR(ret) : lookup.desc;
+}
+
+/**
+ * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
+ * @fwnode: pointer to an ACPI firmware node to get the GPIO information from
+ * @propname: Property name of the GPIO
+ * @index: index of GpioIo/GpioInt resource (starting from %0)
+ * @info: info pointer to fill in (optional)
+ *
+ * If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
+ * Otherwise (ie. it is a data-only non-device object), use the property-based
+ * GPIO lookup to get to the GPIO resource with the relevant information and use
+ * that to obtain the GPIO descriptor to return.
+ */
+struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
+				      const char *propname, int index,
+				      struct acpi_gpio_info *info)
+{
+	struct acpi_gpio_lookup lookup;
+	struct acpi_device *adev;
+	int ret;
+
+	adev = to_acpi_device_node(fwnode);
+	if (adev)
+		return acpi_get_gpiod_by_index(adev, propname, index, info);
+
+	if (!is_acpi_data_node(fwnode))
+		return ERR_PTR(-ENODEV);
+
+	if (!propname)
+		return ERR_PTR(-EINVAL);
+
+	memset(&lookup, 0, sizeof(lookup));
+	lookup.index = index;
+
+	ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
+	if (ret)
 		return ERR_PTR(ret);
 
-	acpi_dev_free_resource_list(&resource_list);
-
-	if (lookup.desc && info) {
-		*info = lookup.info;
-		if (active_low)
-			info->active_low = active_low;
-	}
-
-	return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT);
+	ret = acpi_gpio_resource_lookup(&lookup, info);
+	return ret ? ERR_PTR(ret) : lookup.desc;
 }
 
 /**

drivers/gpio/gpiolib.c

···
 	} else if (is_acpi_node(fwnode)) {
 		struct acpi_gpio_info info;
 
-		desc = acpi_get_gpiod_by_index(to_acpi_node(fwnode), propname, 0,
-					       &info);
+		desc = acpi_node_get_gpiod(fwnode, propname, 0, &info);
 		if (!IS_ERR(desc))
 			active_low = info.active_low;
 	}

drivers/gpio/gpiolib.h

···
 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
 					  const char *propname, int index,
 					  struct acpi_gpio_info *info);
+struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
+				      const char *propname, int index,
+				      struct acpi_gpio_info *info);
 
 int acpi_gpio_count(struct device *dev, const char *con_id);
 #else
···
 {
 	return ERR_PTR(-ENOSYS);
 }
-
+static inline struct gpio_desc *
+acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
+		    int index, struct acpi_gpio_info *info)
+{
+	return ERR_PTR(-ENXIO);
+}
 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
 {
 	return -ENODEV;

include/acpi/acpi_bus.h

···
 	const union acpi_object *pointer;
 	const union acpi_object *properties;
 	const union acpi_object *of_compatible;
+	struct list_head subnodes;
 };
 
 struct acpi_gpio_mapping;
···
 	struct list_head physical_node_list;
 	struct mutex physical_node_lock;
 	void (*remove)(struct acpi_device *);
+};
+
+/* Non-device subnode */
+struct acpi_data_node {
+	const char *name;
+	acpi_handle handle;
+	struct fwnode_handle fwnode;
+	struct acpi_device_data data;
+	struct list_head sibling;
+	struct kobject kobj;
+	struct completion kobj_done;
 };
 
 static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent)
···
 
 static inline bool is_acpi_node(struct fwnode_handle *fwnode)
 {
+	return fwnode && (fwnode->type == FWNODE_ACPI
+		|| fwnode->type == FWNODE_ACPI_DATA);
+}
+
+static inline bool is_acpi_device_node(struct fwnode_handle *fwnode)
+{
 	return fwnode && fwnode->type == FWNODE_ACPI;
 }
 
-static inline struct acpi_device *to_acpi_node(struct fwnode_handle *fwnode)
+static inline struct acpi_device *to_acpi_device_node(struct fwnode_handle *fwnode)
 {
-	return is_acpi_node(fwnode) ?
+	return is_acpi_device_node(fwnode) ?
 		container_of(fwnode, struct acpi_device, fwnode) : NULL;
+}
+
+static inline bool is_acpi_data_node(struct fwnode_handle *fwnode)
+{
+	return fwnode && fwnode->type == FWNODE_ACPI_DATA;
+}
+
+static inline struct acpi_data_node *to_acpi_data_node(struct fwnode_handle *fwnode)
+{
+	return is_acpi_data_node(fwnode) ?
+		container_of(fwnode, struct acpi_data_node, fwnode) : NULL;
 }
 
 static inline struct fwnode_handle *acpi_fwnode_handle(struct acpi_device *adev)

include/linux/acpi.h

···
 	return adev ? adev->handle : NULL;
 }
 
-#define ACPI_COMPANION(dev)		to_acpi_node((dev)->fwnode)
+#define ACPI_COMPANION(dev)		to_acpi_device_node((dev)->fwnode)
 #define ACPI_COMPANION_SET(dev, adev)	set_primary_fwnode(dev, (adev) ? \
 	acpi_fwnode_handle(adev) : NULL)
 #define ACPI_HANDLE(dev)		acpi_device_handle(ACPI_COMPANION(dev))
···
 
 static inline bool has_acpi_companion(struct device *dev)
 {
-	return is_acpi_node(dev->fwnode);
+	return is_acpi_device_node(dev->fwnode);
 }
 
 static inline void acpi_preset_companion(struct device *dev,
···
 	return false;
 }
 
-static inline struct acpi_device *to_acpi_node(struct fwnode_handle *fwnode)
+static inline bool is_acpi_device_node(struct fwnode_handle *fwnode)
+{
+	return false;
+}
+
+static inline struct acpi_device *to_acpi_device_node(struct fwnode_handle *fwnode)
+{
+	return NULL;
+}
+
+static inline bool is_acpi_data_node(struct fwnode_handle *fwnode)
+{
+	return false;
+}
+
+static inline struct acpi_data_node *to_acpi_data_node(struct fwnode_handle *fwnode)
 {
 	return NULL;
 }
···
 #ifdef CONFIG_ACPI
 int acpi_dev_get_property(struct acpi_device *adev, const char *name,
 			  acpi_object_type type, const union acpi_object **obj);
-int acpi_dev_get_property_array(struct acpi_device *adev, const char *name,
-				acpi_object_type type,
-				const union acpi_object **obj);
-int acpi_dev_get_property_reference(struct acpi_device *adev,
-				    const char *name, size_t index,
-				    struct acpi_reference_args *args);
+int acpi_node_get_property_reference(struct fwnode_handle *fwnode,
+				     const char *name, size_t index,
+				     struct acpi_reference_args *args);
 
-int acpi_dev_prop_get(struct acpi_device *adev, const char *propname,
-		      void **valptr);
+int acpi_node_prop_get(struct fwnode_handle *fwnode, const char *propname,
+		       void **valptr);
 int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
 			      enum dev_prop_type proptype, void *val);
+int acpi_node_prop_read(struct fwnode_handle *fwnode, const char *propname,
+		        enum dev_prop_type proptype, void *val, size_t nval);
 int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
 		       enum dev_prop_type proptype, void *val, size_t nval);
 
-struct acpi_device *acpi_get_next_child(struct device *dev,
-					struct acpi_device *child);
+struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
+					    struct fwnode_handle *subnode);
 #else
 static inline int acpi_dev_get_property(struct acpi_device *adev,
 					const char *name, acpi_object_type type,
···
 {
 	return -ENXIO;
 }
-static inline int acpi_dev_get_property_array(struct acpi_device *adev,
-					      const char *name,
-					      acpi_object_type type,
-					      const union acpi_object **obj)
+
+static inline int acpi_node_get_property_reference(struct fwnode_handle *fwnode,
+				const char *name, const char *cells_name,
+				size_t index, struct acpi_reference_args *args)
 {
 	return -ENXIO;
 }
-static inline int acpi_dev_get_property_reference(struct acpi_device *adev,
-				const char *name, const char *cells_name,
-				size_t index, struct acpi_reference_args *args)
+
+static inline int acpi_node_prop_get(struct fwnode_handle *fwnode,
+				     const char *propname,
+				     void **valptr)
 {
 	return -ENXIO;
 }
···
 	return -ENXIO;
 }
 
+static inline int acpi_node_prop_read(struct fwnode_handle *fwnode,
+				      const char *propname,
+				      enum dev_prop_type proptype,
+				      void *val, size_t nval)
+{
+	return -ENXIO;
+}
+
 static inline int acpi_dev_prop_read(struct acpi_device *adev,
 				     const char *propname,
 				     enum dev_prop_type proptype,
···
 	return -ENXIO;
 }
 
-static inline struct acpi_device *acpi_get_next_child(struct device *dev,
-						      struct acpi_device *child)
+static inline struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
+						struct fwnode_handle *subnode)
 {
 	return NULL;
 }
-
 #endif
 
 #endif	/*_LINUX_ACPI_H*/

include/linux/fwnode.h

···
 	FWNODE_INVALID = 0,
 	FWNODE_OF,
 	FWNODE_ACPI,
+	FWNODE_ACPI_DATA,
 	FWNODE_PDATA,
 };
 

include/linux/property.h

···
 				      const char **val, size_t nval);
 int device_property_read_string(struct device *dev, const char *propname,
 				const char **val);
+int device_property_match_string(struct device *dev,
+				 const char *propname, const char *string);
 
 bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname);
 int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
···
 				      size_t nval);
 int fwnode_property_read_string(struct fwnode_handle *fwnode,
 				const char *propname, const char **val);
+int fwnode_property_match_string(struct fwnode_handle *fwnode,
+				 const char *propname, const char *string);
 
 struct fwnode_handle *device_get_next_child_node(struct device *dev,
 						 struct fwnode_handle *child);