Commit d3c2872a authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Tzung-Bi Shih
Browse files

platform/chrome: Convert ChromeOS privacy-screen driver to platform 

In all cases in which a struct acpi_driver is used for binding a driver
to an ACPI device object, a corresponding platform device is created by
the ACPI core and that device is regarded as a proper representation of
underlying hardware.  Accordingly, a struct platform_driver should be
used by driver code to bind to that device.  There are multiple reasons
why drivers should not bind directly to ACPI device objects [1].

Overall, it is better to bind drivers to platform devices than to their
ACPI companions, so convert the ChromeOS privacy-screen ACPI driver
to a platform one.

While this is not expected to alter functionality, it changes sysfs
layout and so it will be visible to user space.

Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/

 [1]
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/1963835.tdWV9SEqCh@rafael.j.wysocki


Signed-off-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
parent 28638682

drivers/platform/chrome/chromeos_privacy_screen.c

+18 −23
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
 */



#include <linux/acpi.h>

#include <linux/platform_device.h>

#include <drm/drm_privacy_screen_driver.h>



/*
@@ -32,11 +33,10 @@ chromeos_privacy_screen_get_hw_state(struct drm_privacy_screen 
				     *drm_privacy_screen)

{

	union acpi_object *obj;

	acpi_handle handle;

	struct device *privacy_screen =

		drm_privacy_screen_get_drvdata(drm_privacy_screen);

	acpi_handle handle = ACPI_HANDLE(privacy_screen);



	handle = acpi_device_handle(to_acpi_device(privacy_screen));

	obj = acpi_evaluate_dsm(handle, &chromeos_privacy_screen_dsm_guid,

				PRIV_SCRN_DSM_REVID,

				PRIV_SCRN_DSM_FN_GET_STATUS, NULL);
@@ -65,11 +65,9 @@ chromeos_privacy_screen_set_sw_state(struct drm_privacy_screen 
				     enum drm_privacy_screen_status state)

{

	union acpi_object *obj = NULL;

	acpi_handle handle;

	struct device *privacy_screen =

		drm_privacy_screen_get_drvdata(drm_privacy_screen);



	handle = acpi_device_handle(to_acpi_device(privacy_screen));

	acpi_handle handle = ACPI_HANDLE(privacy_screen);



	if (state == PRIVACY_SCREEN_DISABLED) {

		obj = acpi_evaluate_dsm(handle,
@@ -104,30 +102,28 @@ static const struct drm_privacy_screen_ops chromeos_privacy_screen_ops = { 
	.set_sw_state = chromeos_privacy_screen_set_sw_state,

};



static int chromeos_privacy_screen_add(struct acpi_device *adev)

static int chromeos_privacy_screen_probe(struct platform_device *pdev)

{

	struct drm_privacy_screen *drm_privacy_screen =

		drm_privacy_screen_register(&adev->dev,

		drm_privacy_screen_register(&pdev->dev,

					    &chromeos_privacy_screen_ops,

					    &adev->dev);

					    &pdev->dev);



	if (IS_ERR(drm_privacy_screen)) {

		dev_err(&adev->dev, "Error registering privacy-screen\n");

		dev_err(&pdev->dev, "Error registering privacy-screen\n");

		return PTR_ERR(drm_privacy_screen);

	}



	adev->driver_data = drm_privacy_screen;

	dev_info(&adev->dev, "registered privacy-screen '%s'\n",

	platform_set_drvdata(pdev, drm_privacy_screen);

	dev_info(&pdev->dev, "registered privacy-screen '%s'\n",

		 dev_name(&drm_privacy_screen->dev));



	return 0;

}



static void chromeos_privacy_screen_remove(struct acpi_device *adev)

static void chromeos_privacy_screen_remove(struct platform_device *pdev)

{

	struct drm_privacy_screen *drm_privacy_screen =	acpi_driver_data(adev);



	drm_privacy_screen_unregister(drm_privacy_screen);

	drm_privacy_screen_unregister(platform_get_drvdata(pdev));

}



static const struct acpi_device_id chromeos_privacy_screen_device_ids[] = {
@@ -136,17 +132,16 @@ static const struct acpi_device_id chromeos_privacy_screen_device_ids[] = { 
};

MODULE_DEVICE_TABLE(acpi, chromeos_privacy_screen_device_ids);



static struct acpi_driver chromeos_privacy_screen_driver = {

	.name = "chromeos_privacy_screen_driver",

	.class = "ChromeOS",

	.ids = chromeos_privacy_screen_device_ids,

	.ops = {

		.add = chromeos_privacy_screen_add,

static struct platform_driver chromeos_privacy_screen_driver = {

	.probe = chromeos_privacy_screen_probe,

	.remove = chromeos_privacy_screen_remove,

	.driver = {

		.name = "chromeos_privacy_screen_driver",

		.acpi_match_table = chromeos_privacy_screen_device_ids,

	},

};



module_acpi_driver(chromeos_privacy_screen_driver);

module_platform_driver(chromeos_privacy_screen_driver);

MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("ChromeOS ACPI Privacy Screen driver");

MODULE_AUTHOR("Rajat Jain <rajatja@google.com>");