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: Barnabás Pőcze <pobrn@xxxxxxxxxxxxxx>
diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86/ideapad-laptop.c
index 075056075b2d..a43574e65f61 100644
--- a/drivers/platform/x86/ideapad-laptop.c
+++ b/drivers/platform/x86/ideapad-laptop.c
@@ -9,6 +9,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <acpi/video.h>
+#include <dt-bindings/leds/common.h>
#include <linux/acpi.h>
#include <linux/backlight.h>
#include <linux/bitops.h>
@@ -22,6 +23,7 @@
#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/rfkill.h>
@@ -56,12 +58,16 @@ 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,
};
@@ -114,6 +120,11 @@ struct ideapad_private {
fn_lock : 1,
hw_rfkill_switch : 1;
} features;
+ struct {
+ bool initialized;
+ struct led_classdev led;
+ unsigned int last_brightness;
+ } kbd_bl;
};
static bool no_bt_rfkill;
@@ -934,6 +945,110 @@ 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;
+
+ err = eval_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)
+{
+ unsigned long hals;
+ int err;
+
+ err = eval_hals(priv->adev->handle, &hals);
+ if (err)
+ return err;
+
+ if (!test_bit(HALS_KBD_BL_SUPPORT_BIT, &hals))
+ return -ENODEV;
+
+ err = ideapad_kbd_bl_brightness_get(priv);
+ if (err < 0)
+ return err;
+
+ priv->kbd_bl.last_brightness = err;
+
+ 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;
+
+ led_classdev_unregister(&priv->kbd_bl.led);
+}
+
/*
* module init/exit
*/
@@ -1000,8 +1115,9 @@ 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.
*/
+ ideapad_kbd_bl_notify(priv);
break;
default:
dev_warn(&priv->platform_device->dev,
@@ -1101,6 +1217,11 @@ static int ideapad_acpi_add(struct platform_device *pdev)
if (err)
goto input_failed;
+ err = ideapad_kbd_bl_init(priv);
+ if (err && err != -ENODEV)
+ dev_warn(&pdev->dev,
+ "Could not register keyboard backlight led: %d\n", err);
+
/*
* 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.
@@ -1161,6 +1282,7 @@ 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:
@@ -1188,6 +1310,7 @@ 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);
--
2.29.2
