Commit 504a3374 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI / property: Extend device_get_next_child_node() to data-only nodes 



Make device_get_next_child_node() work with ACPI data-only subnodes
introduced previously.

Namely, replace acpi_get_next_child() with acpi_get_next_subnode()
that can handle (and return) child device objects as well as child
data-only subnodes of the given device and modify the ACPI part
of the GPIO subsystem to handle data-only subnodes returned by it.

To that end, introduce acpi_node_get_gpiod() taking a struct
fwnode_handle pointer as the first argument.  That argument may
point to an ACPI device object as well as to a data-only subnode
and the function should do the right thing (ie. look for the matching
GPIO descriptor correctly) in either case.

Next, modify fwnode_get_named_gpiod() to use acpi_node_get_gpiod()
instead of acpi_get_gpiod_by_index() which automatically causes
devm_get_gpiod_from_child() to work with ACPI data-only subnodes
that may be returned by device_get_next_child_node() which in turn
is required by the users of that function (the gpio_keys_polled
and gpio-leds drivers).

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent d079524a

drivers/acpi/property.c

+80 −8
Original line number Diff line number Diff line
@@ -461,9 +461,9 @@ static int acpi_data_get_property_array(struct acpi_device_data *data, 
}



/**

 * 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

 *
@@ -477,8 +477,8 @@ static int acpi_data_get_property_array(struct acpi_device_data *data, 
 *

 * 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,

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;
@@ -486,7 +486,7 @@ int acpi_dev_get_property_reference(struct acpi_device *adev, 
	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;
@@ -561,7 +561,23 @@ int acpi_dev_get_property_reference(struct acpi_device *adev, 


	return -EPROTO;

}

EXPORT_SYMBOL_GPL(acpi_dev_get_property_reference);



/**

 * 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)

{

	struct acpi_device_data *data = acpi_device_data_of_node(fwnode);



	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,
@@ -768,3 +784,59 @@ int acpi_node_prop_read(struct fwnode_handle *fwnode, const char *propname, 
	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

+0 −20
Original line number Diff line number Diff line
@@ -695,26 +695,6 @@ int acpi_device_add(struct acpi_device *device, 
	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

+1 −5
Original line number Diff line number Diff line
@@ -493,11 +493,7 @@ struct fwnode_handle *device_get_next_child_node(struct device *dev, 
		if (node)

			return &node->fwnode;

	} else if (IS_ENABLED(CONFIG_ACPI)) {

		struct acpi_device *node;



		node = acpi_get_next_child(dev, to_acpi_device_node(child));

		if (node)

			return acpi_fwnode_handle(node);

		return acpi_get_next_subnode(dev, child);

	}

	return NULL;

}

drivers/gpio/gpiolib-acpi.c

+53 −5
Original line number Diff line number Diff line
@@ -453,7 +453,7 @@ static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup, 
	return 0;

}



static int acpi_gpio_property_lookup(struct acpi_device *adev,

static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,

				     const char *propname, int index,

				     struct acpi_gpio_lookup *lookup)

{
@@ -461,10 +461,16 @@ static int acpi_gpio_property_lookup(struct acpi_device *adev, 
	int ret;



	memset(&args, 0, sizeof(args));

	ret = acpi_dev_get_property_reference(adev, propname, index, &args);

	if (ret && !acpi_get_driver_gpio_data(adev, propname, index, &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.
@@ -518,7 +524,8 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, 
	if (propname) {

		dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);



		ret = acpi_gpio_property_lookup(adev, propname, index, &lookup);

		ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),

						propname, index, &lookup);

		if (ret)

			return ERR_PTR(ret);
@@ -534,6 +541,47 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, 
	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);



	ret = acpi_gpio_resource_lookup(&lookup, info);

	return ret ? ERR_PTR(ret) : lookup.desc;

}



/**

 * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number

 * @adev: pointer to a ACPI device to get IRQ from

drivers/gpio/gpiolib.c

+2 −3
Original line number Diff line number Diff line
@@ -2083,11 +2083,10 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, 
						&flags);

		if (!IS_ERR(desc))

			active_low = flags & OF_GPIO_ACTIVE_LOW;

	} else if (is_acpi_device_node(fwnode)) {

	} else if (is_acpi_node(fwnode)) {

		struct acpi_gpio_info info;



		desc = acpi_get_gpiod_by_index(to_acpi_device_node(fwnode),

					       propname, 0, &info);

		desc = acpi_node_get_gpiod(fwnode, propname, 0, &info);

		if (!IS_ERR(desc))

			active_low = info.active_low;

	}

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