Commit 6b1e5ba3 authored by Tzung-Bi Shih's avatar Tzung-Bi Shih
Browse files

platform/chrome: cros_kbd_led_backlight: separate ACPI backend 



cros_kbd_led_backlight uses ACPI_KEYBOARD_BACKLIGHT_WRITE and
ACPI_KEYBOARD_BACKLIGHT_READ for setting and getting the brightness
respectively.

Separate ACPI operations for preparing the driver to support other
backends.

Signed-off-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: default avatarGuenter Roeck <groeck@chromium.org>
Link: https://lore.kernel.org/r/20220523090822.3035189-3-tzungbi@kernel.org
parent 337eac8f

drivers/platform/chrome/cros_kbd_led_backlight.c

+69 −13
Original line number Diff line number Diff line
@@ -13,6 +13,33 @@ 
#include <linux/platform_device.h>

#include <linux/slab.h>



/**

 * struct keyboard_led_drvdata - keyboard LED driver data.

 * @init:			Init function.

 * @brightness_get:		Get LED brightness level.

 * @brightness_set:		Set LED brightness level.  Must not sleep.

 * @brightness_set_blocking:	Set LED brightness level.  It can block the

 *				caller for the time required for accessing a

 *				LED device register

 * @max_brightness:		Maximum brightness.

 *

 * See struct led_classdev in include/linux/leds.h for more details.

 */

struct keyboard_led_drvdata {

	int (*init)(struct platform_device *pdev);



	enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);



	void (*brightness_set)(struct led_classdev *led_cdev,

			       enum led_brightness brightness);

	int (*brightness_set_blocking)(struct led_classdev *led_cdev,

				       enum led_brightness brightness);



	enum led_brightness max_brightness;

};



#ifdef CONFIG_ACPI



/* Keyboard LED ACPI Device must be defined in firmware */

#define ACPI_KEYBOARD_BACKLIGHT_DEVICE	"\\_SB.KBLT"

#define ACPI_KEYBOARD_BACKLIGHT_READ	ACPI_KEYBOARD_BACKLIGHT_DEVICE ".KBQC"
@@ -20,7 +47,7 @@ 


#define ACPI_KEYBOARD_BACKLIGHT_MAX		100



static void keyboard_led_set_brightness(struct led_classdev *cdev,

static void keyboard_led_set_brightness_acpi(struct led_classdev *cdev,

					     enum led_brightness brightness)

{

	union acpi_object param;
@@ -40,7 +67,7 @@ static void keyboard_led_set_brightness(struct led_classdev *cdev, 
}



static enum led_brightness

keyboard_led_get_brightness(struct led_classdev *cdev)

keyboard_led_get_brightness_acpi(struct led_classdev *cdev)

{

	unsigned long long brightness;

	acpi_status status;
@@ -56,12 +83,10 @@ keyboard_led_get_brightness(struct led_classdev *cdev) 
	return brightness;

}



static int keyboard_led_probe(struct platform_device *pdev)

static int keyboard_led_init_acpi(struct platform_device *pdev)

{

	struct led_classdev *cdev;

	acpi_handle handle;

	acpi_status status;

	int error;



	/* Look for the keyboard LED ACPI Device */

	status = acpi_get_handle(ACPI_ROOT_OBJECT,
@@ -73,15 +98,44 @@ static int keyboard_led_probe(struct platform_device *pdev) 
		return -ENXIO;

	}



	return 0;

}



static const struct keyboard_led_drvdata keyboard_led_drvdata_acpi = {

	.init = keyboard_led_init_acpi,

	.brightness_set = keyboard_led_set_brightness_acpi,

	.brightness_get = keyboard_led_get_brightness_acpi,

	.max_brightness = ACPI_KEYBOARD_BACKLIGHT_MAX,

};



#endif /* CONFIG_ACPI */



static int keyboard_led_probe(struct platform_device *pdev)

{

	struct led_classdev *cdev;

	const struct keyboard_led_drvdata *drvdata;

	int error;



	drvdata = acpi_device_get_match_data(&pdev->dev);

	if (!drvdata)

		return -EINVAL;



	if (drvdata->init) {

		error = drvdata->init(pdev);

		if (error)

			return error;

	}



	cdev = devm_kzalloc(&pdev->dev, sizeof(*cdev), GFP_KERNEL);

	if (!cdev)

		return -ENOMEM;



	cdev->name = "chromeos::kbd_backlight";

	cdev->max_brightness = ACPI_KEYBOARD_BACKLIGHT_MAX;

	cdev->flags |= LED_CORE_SUSPENDRESUME;

	cdev->brightness_set = keyboard_led_set_brightness;

	cdev->brightness_get = keyboard_led_get_brightness;

	cdev->max_brightness = drvdata->max_brightness;

	cdev->brightness_set = drvdata->brightness_set;

	cdev->brightness_set_blocking = drvdata->brightness_set_blocking;

	cdev->brightness_get = drvdata->brightness_get;



	error = devm_led_classdev_register(&pdev->dev, cdev);

	if (error)
@@ -90,16 +144,18 @@ static int keyboard_led_probe(struct platform_device *pdev) 
	return 0;

}



static const struct acpi_device_id keyboard_led_id[] = {

	{ "GOOG0002", 0 },

#ifdef CONFIG_ACPI

static const struct acpi_device_id keyboard_led_acpi_match[] = {

	{ "GOOG0002", (kernel_ulong_t)&keyboard_led_drvdata_acpi },

	{ }

};

MODULE_DEVICE_TABLE(acpi, keyboard_led_id);

MODULE_DEVICE_TABLE(acpi, keyboard_led_acpi_match);

#endif



static struct platform_driver keyboard_led_driver = {

	.driver		= {

		.name	= "chromeos-keyboard-leds",

		.acpi_match_table = ACPI_PTR(keyboard_led_id),

		.acpi_match_table = ACPI_PTR(keyboard_led_acpi_match),

	},

	.probe		= keyboard_led_probe,

};