Commit 503325f8 authored by Barnabás Pőcze's avatar Barnabás Pőcze Committed by Hans de Goede
Browse files

platform/x86: ideapad-laptop: add keyboard backlight control support 



On certain models it is possible to control/query the
keyboard backlight via the SALS/HALS ACPI methods. Add
support for that, and register an LED class device to expose
this functionality. Tested on: Lenovo YOGA 520-14IKB 80X8

Signed-off-by: default avatarBarnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210203215403.290792-27-pobrn@protonmail.com


Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
parent c6795746

drivers/platform/x86/ideapad-laptop.c

+132 −1
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/acpi.h>

#include <linux/backlight.h>

#include <linux/bitops.h>

#include <linux/bug.h>

#include <linux/debugfs.h>

#include <linux/device.h>

#include <linux/dmi.h>
@@ -21,6 +22,7 @@ 
#include <linux/input/sparse-keymap.h>

#include <linux/jiffies.h>

#include <linux/kernel.h>

#include <linux/leds.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/platform_profile.h>
@@ -31,6 +33,8 @@ 


#include <acpi/video.h>



#include <dt-bindings/leds/common.h>



#define IDEAPAD_RFKILL_DEV_NUM	3



#if IS_ENABLED(CONFIG_ACPI_WMI)
@@ -58,12 +62,16 @@ enum { 
};



enum {

	HALS_KBD_BL_SUPPORT_BIT  = 4,

	HALS_KBD_BL_STATE_BIT    = 5,

	HALS_FNLOCK_SUPPORT_BIT  = 9,

	HALS_FNLOCK_STATE_BIT    = 10,

	HALS_HOTKEYS_PRIMARY_BIT = 11,

};



enum {

	SALS_KBD_BL_ON  = 0x8,

	SALS_KBD_BL_OFF = 0x9,

	SALS_FNLOCK_ON  = 0xe,

	SALS_FNLOCK_OFF = 0xf,

};
@@ -124,8 +132,14 @@ struct ideapad_private { 
		bool fan_mode             : 1;

		bool fn_lock              : 1;

		bool hw_rfkill_switch     : 1;

		bool kbd_bl               : 1;

		bool touchpad_ctrl_via_ec : 1;

	} features;

	struct {

		bool initialized;

		struct led_classdev led;

		unsigned int last_brightness;

	} kbd_bl;

};



static bool no_bt_rfkill;
@@ -1200,6 +1214,108 @@ static void ideapad_backlight_notify_brightness(struct ideapad_private *priv) 
		backlight_force_update(priv->blightdev, BACKLIGHT_UPDATE_HOTKEY);

}



/*

 * keyboard backlight

 */

static int ideapad_kbd_bl_brightness_get(struct ideapad_private *priv)

{

	unsigned long hals;

	int err;



	err = eval_hals(priv->adev->handle, &hals);

	if (err)

		return err;



	return !!test_bit(HALS_KBD_BL_STATE_BIT, &hals);

}



static enum led_brightness ideapad_kbd_bl_led_cdev_brightness_get(struct led_classdev *led_cdev)

{

	struct ideapad_private *priv = container_of(led_cdev, struct ideapad_private, kbd_bl.led);



	return ideapad_kbd_bl_brightness_get(priv);

}



static int ideapad_kbd_bl_brightness_set(struct ideapad_private *priv, unsigned int brightness)

{

	int err = exec_sals(priv->adev->handle, brightness ? SALS_KBD_BL_ON : SALS_KBD_BL_OFF);



	if (err)

		return err;



	priv->kbd_bl.last_brightness = brightness;



	return 0;

}



static int ideapad_kbd_bl_led_cdev_brightness_set(struct led_classdev *led_cdev,

						  enum led_brightness brightness)

{

	struct ideapad_private *priv = container_of(led_cdev, struct ideapad_private, kbd_bl.led);



	return ideapad_kbd_bl_brightness_set(priv, brightness);

}



static void ideapad_kbd_bl_notify(struct ideapad_private *priv)

{

	int brightness;



	if (!priv->kbd_bl.initialized)

		return;



	brightness = ideapad_kbd_bl_brightness_get(priv);

	if (brightness < 0)

		return;



	if (brightness == priv->kbd_bl.last_brightness)

		return;



	priv->kbd_bl.last_brightness = brightness;



	led_classdev_notify_brightness_hw_changed(&priv->kbd_bl.led, brightness);

}



static int ideapad_kbd_bl_init(struct ideapad_private *priv)

{

	int brightness, err;



	if (!priv->features.kbd_bl)

		return -ENODEV;



	if (WARN_ON(priv->kbd_bl.initialized))

		return -EEXIST;



	brightness = ideapad_kbd_bl_brightness_get(priv);

	if (brightness < 0)

		return brightness;



	priv->kbd_bl.last_brightness = brightness;



	priv->kbd_bl.led.name                    = "platform::" LED_FUNCTION_KBD_BACKLIGHT;

	priv->kbd_bl.led.max_brightness          = 1;

	priv->kbd_bl.led.brightness_get          = ideapad_kbd_bl_led_cdev_brightness_get;

	priv->kbd_bl.led.brightness_set_blocking = ideapad_kbd_bl_led_cdev_brightness_set;

	priv->kbd_bl.led.flags                   = LED_BRIGHT_HW_CHANGED;



	err = led_classdev_register(&priv->platform_device->dev, &priv->kbd_bl.led);

	if (err)

		return err;



	priv->kbd_bl.initialized = true;



	return 0;

}



static void ideapad_kbd_bl_exit(struct ideapad_private *priv)

{

	if (!priv->kbd_bl.initialized)

		return;



	priv->kbd_bl.initialized = false;



	led_classdev_unregister(&priv->kbd_bl.led);

}



/*

 * module init/exit

 */
@@ -1267,8 +1383,10 @@ static void ideapad_acpi_notify(acpi_handle handle, u32 event, void *data) 
			 * Some IdeaPads report event 1 every ~20

			 * seconds while on battery power; some

			 * report this when changing to/from tablet

			 * mode. Squelch this event.

			 * mode; some report this when the keyboard

			 * backlight has changed.

			 */

			ideapad_kbd_bl_notify(priv);

			break;

		case 0:

			ideapad_check_special_buttons(priv);
@@ -1338,6 +1456,9 @@ static void ideapad_check_features(struct ideapad_private *priv) 
		if (!eval_hals(handle, &val)) {

			if (test_bit(HALS_FNLOCK_SUPPORT_BIT, &val))

				priv->features.fn_lock = true;



			if (test_bit(HALS_KBD_BL_SUPPORT_BIT, &val))

				priv->features.kbd_bl = true;

		}

	}

}
@@ -1379,6 +1500,14 @@ static int ideapad_acpi_add(struct platform_device *pdev) 
	if (err)

		goto input_failed;



	err = ideapad_kbd_bl_init(priv);

	if (err) {

		if (err != -ENODEV)

			dev_warn(&pdev->dev, "Could not set up keyboard backlight LED: %d\n", err);

		else

			dev_info(&pdev->dev, "Keyboard backlight control not available\n");

	}



	/*

	 * On some models without a hw-switch (the yoga 2 13 at least)

	 * VPCCMD_W_RF must be explicitly set to 1 for the wifi to work.
@@ -1453,6 +1582,7 @@ static int ideapad_acpi_add(struct platform_device *pdev) 
	for (i = 0; i < IDEAPAD_RFKILL_DEV_NUM; i++)

		ideapad_unregister_rfkill(priv, i);



	ideapad_kbd_bl_exit(priv);

	ideapad_input_exit(priv);



input_failed:
@@ -1482,6 +1612,7 @@ static int ideapad_acpi_remove(struct platform_device *pdev) 
	for (i = 0; i < IDEAPAD_RFKILL_DEV_NUM; i++)

		ideapad_unregister_rfkill(priv, i);



	ideapad_kbd_bl_exit(priv);

	ideapad_input_exit(priv);

	ideapad_debugfs_exit(priv);

	ideapad_sysfs_exit(priv);