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 76b723f32c84..c3f1b621c92f 100644
--- a/drivers/platform/x86/ideapad-laptop.c
+++ b/drivers/platform/x86/ideapad-laptop.c
@@ -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>
@@ -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/platform_profile.h>
@@ -32,6 +34,8 @@
#include <acpi/video.h>
+#include <dt-bindings/leds/common.h>
+
#define IDEAPAD_RFKILL_DEV_NUM 3
#if IS_ENABLED(CONFIG_ACPI_WMI)
@@ -59,12 +63,16 @@ 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,
};
@@ -125,8 +133,14 @@ 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;
@@ -1203,6 +1217,108 @@ 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
*/
@@ -1270,8 +1386,10 @@ 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);
@@ -1341,6 +1459,9 @@ 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;
}
}
}
@@ -1382,6 +1503,14 @@ 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.
@@ -1456,6 +1585,7 @@ 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:
@@ -1485,6 +1615,7 @@ 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);
--
2.30.0
