Merge tag 'leds-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux-leds

Pull LED updates from Pavel Machek:
 "Usual driver changes, some documentation that should hopefully get LED
  names standartized, and many fixes"

* tag 'leds-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux-leds: (32 commits)
  leds: pca955x: Switch to i2c probe_new
  leds: pca955x: Let the core process the fwnode
  leds: pca955x: Implement the default-state property
  leds: pca955x: Add brightness_get function
  leds: pca955x: Clean up code formatting
  leds: leds-core: Implement the retain-state-shutdown property
  dt-bindings: leds: Add retain-state-shutdown boolean
  Documentation: leds: standartizing LED names
  leds: trigger: remove reference to obsolete CONFIG_IDE_GD_ATA
  leds: lp50xx: Fix chip name in KConfig
  leds: pwm: add support for default-state device property
  leds: move default_state read from fwnode to core
  leds: flash: Remove redundant initialization of variable ret
  leds: lgm-sso: Propagate error codes from callee to caller
  leds: trigger: audio: Add an activate callback to ensure the initial brightness is set
  leds: rt8515: Put fwnode in any case during ->probe()
  leds: lt3593: Put fwnode in any case during ->probe()
  leds: lm3697: Make error handling more robust
  leds: lm3697: Update header block to reflect reality
  leds: lm3692x: Correct headers (of*.h -> mod_devicetable.h)
  ...

2 files changed, 64 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/leds/common.yaml b/Documentation/devicetree/bindings/leds/common.yaml
index b1f363747a62..697102707703 100644
--- a/Documentation/devicetree/bindings/leds/common.yaml
+++ b/Documentation/devicetree/bindings/leds/common.yaml
@@ -128,6 +128,12 @@ properties:
       as a panic indicator.
     type: boolean
 
+  retain-state-shutdown:
+    description:
+      This property specifies that the LED should not be turned off or changed
+      when the system shuts down.
+    type: boolean
+
   trigger-sources:
     description: |
       List of devices which should be used as a source triggering this LED
diff --git a/Documentation/leds/well-known-leds.txt b/Documentation/leds/well-known-leds.txt
new file mode 100644
index 000000000000..4a8b9dc4bf52
--- /dev/null
+++ b/Documentation/leds/well-known-leds.txt
@@ -0,0 +1,58 @@
+-*- 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 .
+
+* 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
+
+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)
+
+* Screen
+
+Good: ":backlight" (Motorola Droid 4)