platform/x86: dell-laptop: Register ctl-led for speaker-mute

Some platforms have the speaker-mute led and
current driver doesn't control it.

If the platform support the control of speaker-mute led, register it
Signed-off-by: Koba Ko <koba.ko@canonical.com>
Link: https://lore.kernel.org/r/20230308062414.1048913-1-koba.ko@canonical.comReviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/dell/dell-laptop.c

@@ -97,6 +97,7 @@ static struct rfkill *bluetooth_rfkill;
 static struct rfkill *wwan_rfkill;
 static bool force_rfkill;
 static bool micmute_led_registered;
+static bool mute_led_registered;
 
 module_param(force_rfkill, bool, 0444);
 MODULE_PARM_DESC(force_rfkill, "enable rfkill on non whitelisted models");
@@ -2177,6 +2178,34 @@ static struct led_classdev micmute_led_cdev = {
 	.default_trigger = "audio-micmute",
 };
 
+static int mute_led_set(struct led_classdev *led_cdev,
+			   enum led_brightness brightness)
+{
+	struct calling_interface_buffer buffer;
+	struct calling_interface_token *token;
+	int state = brightness != LED_OFF;
+
+	if (state == 0)
+		token = dell_smbios_find_token(GLOBAL_MUTE_DISABLE);
+	else
+		token = dell_smbios_find_token(GLOBAL_MUTE_ENABLE);
+
+	if (!token)
+		return -ENODEV;
+
+	dell_fill_request(&buffer, token->location, token->value, 0, 0);
+	dell_send_request(&buffer, CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
+
+	return 0;
+}
+
+static struct led_classdev mute_led_cdev = {
+	.name = "platform::mute",
+	.max_brightness = 1,
+	.brightness_set_blocking = mute_led_set,
+	.default_trigger = "audio-mute",
+};
+
 static int __init dell_init(void)
 {
 	struct calling_interface_token *token;
@@ -2230,6 +2259,15 @@ static int __init dell_init(void)
 		micmute_led_registered = true;
 	}
 
+	if (dell_smbios_find_token(GLOBAL_MUTE_DISABLE) &&
+	    dell_smbios_find_token(GLOBAL_MUTE_ENABLE)) {
+		mute_led_cdev.brightness = ledtrig_audio_get(LED_AUDIO_MUTE);
+		ret = led_classdev_register(&platform_device->dev, &mute_led_cdev);
+		if (ret < 0)
+			goto fail_backlight;
+		mute_led_registered = true;
+	}
+
 	if (acpi_video_get_backlight_type() != acpi_backlight_vendor)
 		return 0;
 
@@ -2277,6 +2315,8 @@ static int __init dell_init(void)
 fail_backlight:
 	if (micmute_led_registered)
 		led_classdev_unregister(&micmute_led_cdev);
+	if (mute_led_registered)
+		led_classdev_unregister(&mute_led_cdev);
 fail_led:
 	dell_cleanup_rfkill();
 fail_rfkill:
@@ -2299,6 +2339,8 @@ static void __exit dell_exit(void)
 	backlight_device_unregister(dell_backlight_device);
 	if (micmute_led_registered)
 		led_classdev_unregister(&micmute_led_cdev);
+	if (mute_led_registered)
+		led_classdev_unregister(&mute_led_cdev);
 	dell_cleanup_rfkill();
 	if (platform_device) {
 		platform_device_unregister(platform_device);

drivers/platform/x86/dell/dell-smbios.h

@@ -34,6 +34,8 @@
 #define KBD_LED_AUTO_100_TOKEN	0x02F6
 #define GLOBAL_MIC_MUTE_ENABLE	0x0364
 #define GLOBAL_MIC_MUTE_DISABLE	0x0365
+#define GLOBAL_MUTE_ENABLE	0x058C
+#define GLOBAL_MUTE_DISABLE	0x058D
 
 struct notifier_block;