From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- Documentation/leds/well-known-leds.txt | 103 +++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) create mode 100644 Documentation/leds/well-known-leds.txt (limited to 'Documentation/leds/well-known-leds.txt') diff --git a/Documentation/leds/well-known-leds.txt b/Documentation/leds/well-known-leds.txt new file mode 100644 index 0000000000..67b4470480 --- /dev/null +++ b/Documentation/leds/well-known-leds.txt @@ -0,0 +1,103 @@ +-*- org -*- + +It is somehow important to provide consistent interface to the +userland. LED devices have one problem there, and that is naming of +directories in /sys/class/leds. It would be nice if userland would +just know right "name" for given LED function, but situation got more +complex. + +Anyway, if backwards compatibility is not an issue, new code should +use one of the "good" names from this list, and you should extend the +list where applicable. + +Legacy names are listed, too; in case you are writing application that +wants to use particular feature, you should probe for good name, first, +but then try the legacy ones, too. + +Notice there's a list of functions in include/dt-bindings/leds/common.h . + +* Gamepads and joysticks + +Game controllers may feature LEDs to indicate a player number. This is commonly +used on game consoles in which multiple controllers can be connected to a system. +The "player LEDs" are then programmed with a pattern to indicate a particular +player. For example, a game controller with 4 LEDs, may be programmed with "x---" +to indicate player 1, "-x--" to indicate player 2 etcetera where "x" means on. +Input drivers can utilize the LED class to expose the individual player LEDs +of a game controller using the function "player". +Note: tracking and management of Player IDs is the responsibility of user space, +though drivers may pick a default value. + +Good: "input*:*:player-{1,2,3,4,5} + +* Keyboards + +Good: "input*:*:capslock" +Good: "input*:*:scrolllock" +Good: "input*:*:numlock" +Legacy: "shift-key-light" (Motorola Droid 4, capslock) + +Set of common keyboard LEDs, going back to PC AT or so. + +Legacy: "tpacpi::thinklight" (IBM/Lenovo Thinkpads) +Legacy: "lp5523:kb{1,2,3,4,5,6}" (Nokia N900) + +Frontlight/backlight of main keyboard. + +Legacy: "button-backlight" (Motorola Droid 4) + +Some phones have touch buttons below screen; it is different from main +keyboard. And this is their backlight. + +* Sound subsystem + +Good: "platform:*:mute" +Good: "platform:*:micmute" + +LEDs on notebook body, indicating that sound input / output is muted. + +* System notification + +Good: "rgb:status" +Legacy: "status-led:{red,green,blue}" (Motorola Droid 4) +Legacy: "lp5523:{r,g,b}" (Nokia N900) + +Phones usually have multi-color status LED. + +* Power management + +Good: "platform:*:charging" (allwinner sun50i, leds-cht-wcove) + +* Screen + +Good: ":backlight" (Motorola Droid 4) + +* Ethernet LEDs + +Currently two types of Network LEDs are support, those controlled by +the PHY and those by the MAC. In theory both can be present at the +same time for one Linux netdev, hence the names need to differ between +MAC and PHY. + +Do not use the netdev name, such as eth0, enp1s0. These are not stable +and are not unique. They also don't differentiate between MAC and PHY. + +** MAC LEDs + +Good: f1070000.ethernet:white:WAN +Good: mdio_mux-0.1:00:green:left +Good: 0000:02:00.0:yellow:top + +The first part must uniquely name the MAC controller. Then follows the +colour. WAN/LAN should be used for a single LED. If there are +multiple LEDs, use left/right, or top/bottom to indicate their +position on the RJ45 socket. + +** PHY LEDs + +Good: f1072004.mdio-mii:00: white:WAN +Good: !mdio-mux!mdio@2!switch@0!mdio:01:green:right +Good: r8169-0-200:00:yellow:bottom + +The first part must uniquely name the PHY. This often means uniquely +identifying the MDIO bus controller, and the address on the bus. -- cgit v1.2.3