Re: [PATCH v3 1/9] leds: multicolor: Add sysfs interface definition

From: Jacek Anaszewski
Date: Mon May 27 2019 - 16:04:06 EST


Hi Dan,

Thank you for the update.

One thing is missing here - we need to document how legacy brightness
levels map to the sub-LED color levels, i.e. what you do in
multicolor_set_brightness().

Best regards,
Jacek Anaszewski

On 5/23/19 9:08 PM, Dan Murphy wrote:
Add a documentation of LED Multicolor LED class specific
sysfs attributes.

Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
---
.../ABI/testing/sysfs-class-led-multicolor | 57 +++++++++++++++++++
1 file changed, 57 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor

diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor
new file mode 100644
index 000000000000..2f102ede258b
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-led-multicolor
@@ -0,0 +1,57 @@
+What: /sys/class/leds/<led>/colors/sync_enable
+Date: April 2019
+KernelVersion: 5.2
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: read/write
+ Writing a 1 to this file will enable the synchronization of all
+ the defined color LEDs within the LED node. Brightness values
+ for each LED will be stored and written when sync is set to 1.
+ Writing a 0 to this file will disable syncing and allow
+ individual control of the LEDs brightness settings.
+
+What: /sys/class/leds/<led>/colors/sync
+Date: April 2019
+KernelVersion: 5.2
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: write only
+ Writing a 1 to this file while sync_enable is set to 1 will
+ write the current brightness values to all defined LEDs within
+ the LED node. All LEDs defined will be configured based
+ on the brightness that has been requested.
+
+ If sync_enable is set to 0 then writing a 1 to sync has no
+ affect on the LEDs.
+
+What: /sys/class/leds/<led>/colors/<led_color>/brightness
+Date: April 2019
+KernelVersion: 5.2
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: read/write
+ The led_color directory is dynamically created based on the
+ colors defined by the registrar of the class.
+ The led_color can be but not limited to red, green, blue,
+ white, amber, yellow and violet. Drivers can also declare a
+ LED color for presentation. There is one directory per color
+ presented. The brightness file is created under each
+ led_color directory and controls the individual LED color
+ setting.
+
+ If sync is enabled then writing the brightness value of the LED
+ is deferred until a 1 is written to
+ /sys/class/leds/<led>/color/sync. If syncing is
+ disabled then the LED brightness value will be written
+ immediately to the LED driver.
+
+ The value of the color is from 0 to
+ /sys/class/leds/<led>/colors/<led_color>/max_brightness.
+
+What: /sys/class/leds/<led>/colors/<led_color>/max_brightness
+Date: April 2019
+KernelVersion: 5.2
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: read only
+ Maximum brightness level for the LED color, default is
+ 255 (LED_FULL).
+
+ If the LED does not support different brightness levels, this
+ should be 1.