[PATCH] leds: Document standard LED functions

[Jacek Anaszewski <jacek.anaszewski@gmail.com>]

Add a documentation for standard LED functions with regard
to differences in meaning between cases when devicename section
of an LED name is present or not.

Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
---
 Documentation/leds/led-functions.rst | 226 +++++++++++++++++++++++++++++++++++
 1 file changed, 226 insertions(+)
 create mode 100644 Documentation/leds/led-functions.rst

diff --git a/Documentation/leds/led-functions.rst b/Documentation/leds/led-functions.rst
new file mode 100644
index 000000000000..42621dd81235
--- /dev/null
+++ b/Documentation/leds/led-functions.rst
@@ -0,0 +1,226 @@
+============================================
+Standardized LED functions and their meaning
+============================================
+
+Each LED function is described using below template:
+
+LED function name
+-----------------
+
+    NDEV : <function meaning when LED devicename section is absent>
+    DEV  : <function meaning when LED devicename section is present>
+    DEVICENAME : <expected LED devicename for DEV case>
+    TRIGGER: <matching LED trigger>
+
+LED functions with corresponding LED trigger support
+----------------------------------------------------
+
+- activity
+    NDEV : system activity
+    DEV  : n/a
+    TRIGGER : "activity"
+
+- backlight
+    NDEV : when there is a single one on the platform
+    DEV  : backlight of a frame buffer device
+    DEVICENAME : associated frame buffer device, e.g. fb0
+    TRIGGER: "backlight"
+
+- disk
+    NDEV : rw activity on any disk in the system
+    DEV  : rw activity on specified disk
+    DEVICENAME : associated disk, e.g.: hda, sdb
+    TRIGGER : "disk-activity", applies only to NDEV case
+
+- disk-read / disk-write
+    NDEV : read / write activity on any disk in the system
+    DEV  : read / write  activity on specified disk
+    DEVICENAME : associted disk, e.g.: hda, sdb
+    TRIGGER : "disk-read" / "disk-write" , applies only to NDEV case
+
+- flash
+    NDEV : flash LED (if there is single available on the platform)
+    DEV  : flash LED related to the specified video device
+    DEVICENAME : associated video device, e.g. v4l2-subdev3
+    TRIGGER : "flash"; this LED can be also controlled by v4l2-flash framework
+
+- flash-front
+    NDEV : n/a
+    DEV  : front flash LED related to the specified video device
+    DEVICENAME : associated video device, e.g. v4l2-subdev3
+    TRIGGER : "flash"; this LED can be also controlled by v4l2-flash framework
+
+- flash-rear
+    NDEV : n/a
+    DEV  : rear flash LED related to the specified video device
+    DEVICENAME : associated video device, e.g. v4l2-subdev3
+    TRIGGER : "flash"; this LED can be also controlled by v4l2-flash framework
+
+- heartbeat
+    NDEV : cpu load average expressed as heartbeat-fashion blink frequency
+    DEV  : n/a
+    TRIGGER : "heartbeat"
+
+- lan
+    NDEV : n/a
+    DEV  : network traffic on selected network device
+    DEVICENAME : associated phy, e.g. phy1
+    TRIGGER : "netdev"
+
+- wlan
+    NDEV : activity on any wlan device
+    DEV  : activity on a specified wlan device
+    DEVICENAME: associated phy, e.g. phy1
+    TRIGGER: wlan device drivers may implement their own triggers
+             using phyN-function naming
+
+- mute
+    NDEV : platform audio output mute state
+    DEV  : mute state of specified audio device output
+    DEVICENAME : associated audio device
+    TRIGGER : "audio-mute"
+
+- micmute
+    NDEV : plaform microphone input mute state
+    DEV  : mute state of a microphone belonging to the specified device
+    DEVICENAME : associated audio device
+    TRIGGER : "audio-micmute"
+
+- mtd
+    NDEV : rw actvity on any mtd device in the system
+    DEV  : rw actvity on specified mtd device
+    DEVICENAME : associated mtd device, e.g mtdN
+    TRIGGER : "mtd"
+
+- panic
+    NDEV : signals kernel panic
+    DEV  : n/a
+    TRIGGER : "panic"
+
+- torch
+    NDEV : torch LED (if there is single available on the platform)
+    DEV  : torch LED related to the specified video device
+    DEVICENAME : associated video device, e.g. video1, v4l2-subdev3
+    TRIGGER : "torch"; this LED can be also controlled by v4l2-flash framework
+
+- usb
+    NDEV : activity on any USB port
+    DEV  : activity on a specified USB port
+    DEVICENAME: associated USB device identifier
+    TRIGGER : "usbport"
+
+- numlock
+    NDEV : n/a
+    DEV  : keyboard numlock state related to the specified input device
+    DEVICENAME : associated input device, e.g. input1
+    TRIGGER : "kbd-numlock"
+
+- capslock
+    NDEV : n/a
+    DEV  : keyboard capslock state related to the specified input device
+    DEVICENAME : associated input device, e.g. input1
+    TRIGGER : "kbd-capslock"
+
+- scrolllock
+    NDEV : n/a
+    DEV  : keyboard scrollock state related to the specified input device
+    DEVICENAME : associated input device, e.g. input1
+    TRIGGER : "kbd-scrolllock"
+
+
+LED functions without corresponding trigger support
+---------------------------------------------------
+
+- alarm
+    NDEV : system wide alarm
+    DEV  : n/a
+
+- bluetooth
+    NDEV : activity on platform bluetooth adapter
+    DEV  : activity on bluetooth adapter related to the specified device
+    DEVICENAME : associated device
+
+- boot
+    NDEV : when lit indicates system boot
+    DEV  : n/a
+
+- charging
+    NDEV : battery charging status
+    DEV  : n/a
+
+- debug
+    NDEV : signals if device runs in debug mode
+    DEV  : n/a
+
+- disk-err
+    NDEV : failure on any disk in the system
+    DEV  : failure on specified disk
+    DEVICENAME : associted disk, e.g.: hda, sdb
+
+- fault
+    NDEV : general system fault
+    DEV  : fault on specified system device
+    DEVICENAME : related device name
+
+- indicator
+    NDEV : signals if platform camera sensor is active
+    DEV  : signals if camera sensor related to the specified video device is active
+    DEVICENAME : associated video device, e.g.: v4l2-subdev3
+
+- kbd_backlight
+    NDEV : platform keyboard backlight state
+    DEV  : backlight state related to the specified device
+    DEVICENAME : associated device, e.g. input1
+
+- mail
+    NDEV : signals a new massage in mailbox
+    DEV  : n/a
+
+- programming
+    NDEV : platform firmware update is in progress
+    DEV  : n/a
+
+- power
+    NDEV : power plug presence indicator
+    DEV  : n/a
+
+- rx
+    NDEV : n/a
+    DEV  : activity on rx line of serial port related to the specified tty device
+    DEVICENAME: associated tty device, e.g.: tty1, ttyUSB2
+
+- tx
+    NDEV : n/a
+    DEV  : activity on tx line of serial port related to the specified tty device
+    DEVICENAME: associated tty device, e.g.: tty1, ttyUSB2
+
+- sd
+    NDEV : n/a
+    DEV  : activity on sd card related to the specified device
+    DEVICENAME: associated disk, e.g. sdb
+
+- sleep
+    NDEV : signals any variant of system hibernation or suspend state
+    DEV  : n/a
+
+- standby
+    NDEV : device standby status
+    DEV  : n/a
+
+- status
+    NDEV : system wide status LED
+    DEV  : n/a
+
+- system
+    NDEV : system is fully operating
+    DEV  : n/a
+
+- wan
+    NDEV : activity on any WAN device
+    DEV  : activity on a specified WAN device
+    DEVICENAME: associated WAN device identifier
+
+- wps
+    NDEV : n/a
+    DEV  : wps functionality activation state related to the specified device
+    DEVICENAME : associated device name
-- 
2.11.0