leds: make functions easier to understand

Group LED functions according to functionality, and add some
explaining comments.
Signed-off-by: Pavel Machek <pavel@ucw.cz>

include/dt-bindings/leds/common.h

@@ -6,6 +6,7 @@
  * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
  *
  * Copyright (C) 2019 Jacek Anaszewski <jacek.anaszewski@gmail.com>
+ * Copyright (C) 2020 Pavel Machek <pavel@ucw.cz>
  */
 
 #ifndef __DT_BINDINGS_LEDS_H
@@ -32,16 +33,38 @@
 #define LED_COLOR_ID_MAX	8
 
 /* Standard LED functions */
+/* Keyboard LEDs, usually it would be input4::capslock etc. */
+/*   Obsolete equivalent: "shift-key-light" */
+#define LED_FUNCTION_CAPSLOCK "capslock"
+#define LED_FUNCTION_SCROLLLOCK "scrolllock"
+#define LED_FUNCTION_NUMLOCK "numlock"
+/*   Obsolete equivalents: "tpacpi::thinklight" (IBM/Lenovo Thinkpads),
+     "lp5523:kb{1,2,3,4,5,6}" (Nokia N900) */
+#define LED_FUNCTION_KBD_BACKLIGHT "kbd_backlight"
+
+/* System LEDs, usually found on system body.
+   platform::mute (etc) is sometimes seen, :mute would be better */
+#define LED_FUNCTION_POWER "power"
+#define LED_FUNCTION_DISK "disk"
+
+/*   Obsolete: "platform:*:charging" (allwinner sun50i) */
+#define LED_FUNCTION_CHARGING "charging"
+/*   Used RGB notification LEDs common on phones.
+     Obsolete equivalents: "status-led:{red,green,blue}" (Motorola Droid 4),
+     "lp5523:{r,g,b}" (Nokia N900) */
+#define LED_FUNCTION_STATUS "status"
+
+#define LED_FUNCTION_MICMUTE "micmute"
+#define LED_FUNCTION_MUTE "mute"
+
+/* Miscelleaus functions. Use functions above if you can. */
 #define LED_FUNCTION_ACTIVITY "activity"
 #define LED_FUNCTION_ALARM "alarm"
 #define LED_FUNCTION_BACKLIGHT "backlight"
 #define LED_FUNCTION_BLUETOOTH "bluetooth"
 #define LED_FUNCTION_BOOT "boot"
 #define LED_FUNCTION_CPU "cpu"
-#define LED_FUNCTION_CAPSLOCK "capslock"
-#define LED_FUNCTION_CHARGING "charging"
 #define LED_FUNCTION_DEBUG "debug"
-#define LED_FUNCTION_DISK "disk"
 #define LED_FUNCTION_DISK_ACTIVITY "disk-activity"
 #define LED_FUNCTION_DISK_ERR "disk-err"
 #define LED_FUNCTION_DISK_READ "disk-read"
@@ -50,21 +73,14 @@
 #define LED_FUNCTION_FLASH "flash"
 #define LED_FUNCTION_HEARTBEAT "heartbeat"
 #define LED_FUNCTION_INDICATOR "indicator"
-#define LED_FUNCTION_KBD_BACKLIGHT "kbd_backlight"
 #define LED_FUNCTION_LAN "lan"
 #define LED_FUNCTION_MAIL "mail"
 #define LED_FUNCTION_MTD "mtd"
-#define LED_FUNCTION_MICMUTE "micmute"
-#define LED_FUNCTION_MUTE "mute"
-#define LED_FUNCTION_NUMLOCK "numlock"
 #define LED_FUNCTION_PANIC "panic"
 #define LED_FUNCTION_PROGRAMMING "programming"
-#define LED_FUNCTION_POWER "power"
 #define LED_FUNCTION_RX "rx"
 #define LED_FUNCTION_SD "sd"
-#define LED_FUNCTION_SCROLLLOCK "scrolllock"
 #define LED_FUNCTION_STANDBY "standby"
-#define LED_FUNCTION_STATUS "status"
 #define LED_FUNCTION_TORCH "torch"
 #define LED_FUNCTION_TX "tx"
 #define LED_FUNCTION_USB "usb"