Commit f6bae04a authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Rafael J. Wysocki
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ACPI: sysfs: manage attributes as attribute_group 



The current manual attribute management is inconsistent and brittle.

Not all return values of device_create_file() are checked and the
cleanup logic needs to be kept up to date manually.

Moving all attributes into an attribute_group and using the is_visible()
callback allows the management of all attributes as a single unit.

Signed-off-by: default avatarThomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20240709-acpi-sysfs-groups-v2-3-058ab0667fa8@weissschuh.net


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 52831d9b

drivers/acpi/device_sysfs.c

+71 −96
Original line number Diff line number Diff line
@@ -517,88 +517,97 @@ static ssize_t status_show(struct device *dev, struct device_attribute *attr, 
}

static DEVICE_ATTR_RO(status);



/**

 * acpi_device_setup_files - Create sysfs attributes of an ACPI device.

 * @dev: ACPI device object.

 */

int acpi_device_setup_files(struct acpi_device *dev)

{

	int result = 0;

static struct attribute *acpi_attrs[] = {

	&dev_attr_path.attr,

	&dev_attr_hid.attr,

	&dev_attr_modalias.attr,

	&dev_attr_description.attr,

	&dev_attr_adr.attr,

	&dev_attr_uid.attr,

	&dev_attr_sun.attr,

	&dev_attr_hrv.attr,

	&dev_attr_status.attr,

	&dev_attr_eject.attr,

	&dev_attr_power_state.attr,

	&dev_attr_real_power_state.attr,

	NULL

};



static bool acpi_show_attr(struct acpi_device *dev, const struct device_attribute *attr)

{

	/*

	 * Devices gotten from FADT don't have a "path" attribute

	 */

	if (dev->handle) {

		result = device_create_file(&dev->dev, &dev_attr_path);

		if (result)

			goto end;

	}

	if (attr == &dev_attr_path)

		return dev->handle;



	if (!list_empty(&dev->pnp.ids)) {

		result = device_create_file(&dev->dev, &dev_attr_hid);

		if (result)

			goto end;

	if (attr == &dev_attr_hid || attr == &dev_attr_modalias)

		return !list_empty(&dev->pnp.ids);



		result = device_create_file(&dev->dev, &dev_attr_modalias);

		if (result)

			goto end;

	}

	if (attr == &dev_attr_description)

		return acpi_has_method(dev->handle, "_STR");



	/*

	 * If device has _STR, 'description' file is created

	 */

	if (acpi_has_method(dev->handle, "_STR")) {

		result = device_create_file(&dev->dev, &dev_attr_description);

		if (result)

			goto end;

	}

	if (attr == &dev_attr_adr)

		return dev->pnp.type.bus_address;



	if (dev->pnp.type.bus_address)

		result = device_create_file(&dev->dev, &dev_attr_adr);

	if (acpi_device_uid(dev))

		result = device_create_file(&dev->dev, &dev_attr_uid);

	if (attr == &dev_attr_uid)

		return acpi_device_uid(dev);



	if (acpi_has_method(dev->handle, "_SUN")) {

		result = device_create_file(&dev->dev, &dev_attr_sun);

		if (result)

			goto end;

	}

	if (attr == &dev_attr_sun)

		return acpi_has_method(dev->handle, "_SUN");



	if (acpi_has_method(dev->handle, "_HRV")) {

		result = device_create_file(&dev->dev, &dev_attr_hrv);

		if (result)

			goto end;

	}

	if (attr == &dev_attr_hrv)

		return acpi_has_method(dev->handle, "_HRV");



	if (acpi_has_method(dev->handle, "_STA")) {

		result = device_create_file(&dev->dev, &dev_attr_status);

		if (result)

			goto end;

	}

	if (attr == &dev_attr_status)

		return acpi_has_method(dev->handle, "_STA");



	/*

	 * If device has _EJ0, 'eject' file is created that is used to trigger

	 * hot-removal function from userland.

	 */

	if (acpi_has_method(dev->handle, "_EJ0")) {

		result = device_create_file(&dev->dev, &dev_attr_eject);

		if (result)

			return result;

	if (attr == &dev_attr_eject)

		return acpi_has_method(dev->handle, "_EJ0");



	if (attr == &dev_attr_power_state)

		return dev->flags.power_manageable;



	if (attr == &dev_attr_real_power_state)

		return dev->flags.power_manageable && dev->power.flags.power_resources;



	dev_warn_once(&dev->dev, "Unexpected attribute: %s\n", attr->attr.name);

	return false;

}



	if (dev->flags.power_manageable) {

		result = device_create_file(&dev->dev, &dev_attr_power_state);

		if (result)

			return result;

static umode_t acpi_attr_is_visible(struct kobject *kobj,

				    struct attribute *attr,

				    int attrno)

{

	struct acpi_device *dev = to_acpi_device(kobj_to_dev(kobj));



		if (dev->power.flags.power_resources)

			result = device_create_file(&dev->dev,

						    &dev_attr_real_power_state);

	if (acpi_show_attr(dev, container_of(attr, struct device_attribute, attr)))

		return attr->mode;

	else

		return 0;

}



static const struct attribute_group acpi_group = {

	.attrs = acpi_attrs,

	.is_visible = acpi_attr_is_visible,

};



/**

 * acpi_device_setup_files - Create sysfs attributes of an ACPI device.

 * @dev: ACPI device object.

 */

int acpi_device_setup_files(struct acpi_device *dev)

{

	int result = 0;



	result = device_add_group(&dev->dev, &acpi_group);



	acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);



end:

	return result;

}
@@ -609,39 +618,5 @@ int acpi_device_setup_files(struct acpi_device *dev) 
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)

			device_remove_file(&dev->dev,

					   &dev_attr_real_power_state);

	}



	/*

	 * If device has _STR, remove 'description' file

	 */

	if (acpi_has_method(dev->handle, "_STR"))

		device_remove_file(&dev->dev, &dev_attr_description);

	/*

	 * If device has _EJ0, remove 'eject' file.

	 */

	if (acpi_has_method(dev->handle, "_EJ0"))

		device_remove_file(&dev->dev, &dev_attr_eject);



	if (acpi_has_method(dev->handle, "_SUN"))

		device_remove_file(&dev->dev, &dev_attr_sun);



	if (acpi_has_method(dev->handle, "_HRV"))

		device_remove_file(&dev->dev, &dev_attr_hrv);



	if (acpi_device_uid(dev))

		device_remove_file(&dev->dev, &dev_attr_uid);

	if (dev->pnp.type.bus_address)

		device_remove_file(&dev->dev, &dev_attr_adr);

	device_remove_file(&dev->dev, &dev_attr_modalias);

	device_remove_file(&dev->dev, &dev_attr_hid);

	if (acpi_has_method(dev->handle, "_STA"))

		device_remove_file(&dev->dev, &dev_attr_status);

	if (dev->handle)

		device_remove_file(&dev->dev, &dev_attr_path);

	device_remove_group(&dev->dev, &acpi_group);

}