Dan,
On 1/30/19 8:59 PM, Dan Murphy wrote:
Jacek
On 1/30/19 1:37 PM, Jacek Anaszewski wrote:
Hi Dan,
Thank you for the RFC.
One vital thing is missing - documentation of brightness file must
be updated to define its semantics for LED multi color class.
Either we need brightness-model file returning only "onoff" option
available, or, for time being, fix the max_brightness for LED multi
color class to 1 (which will map to max intensity level for each color).
I can make max_brightness default to 1 if not set by the LED driver.
But the LP50xx has brightness controls so setting max_brightness from the driver should over ride
the max of 1 in the upper level.
Yes, so the max_brightness should be updated basing on current
brightness-model. For LEDn_BRIGHTNESS of LP50xx we could have
"hw" or maybe even better just "lp50xx-linear" and "lp50xx-logarithmic"
- I just forgot about that capability of the device.
For devices that do not support brightness as a separate control we can create a file called
max_brightness_<color> that defines the max that a specific color can be set to. If max_brightness
is set to 1 then create max_brightness_<color>. If max_brightness > 1 then do not create the files.
Right. We will need dedicated max_brightness for each color.
They should be placed also in the colors directory, next to the color
files.
I don't think we have fully vetted the brightness-model yet so I prefer to omit
it and possibly introduce that later.
We need to start from something. It will give better overview of the
whole idea.
Best regards,
Jacek Anaszewski
Dan
Best regards,
Jacek Anaszewski
On 1/30/19 7:30 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 | 38 +++++++++++++++++++
1 file changed, 38 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..19f8da9b150e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-led-multicolor
@@ -0,0 +1,38 @@
+What: /sys/class/leds/<led>/color/sync_enable
+Date: January 2019
+KernelVersion: 5.0
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: read/write
+ Writing a 1 to this file will enable the sychronization of all
+ the defined color LEDs within the LED node. Writing a 0 to
+ this file will disable syncing.
+
+What: /sys/class/leds/<led>/color/sync
+Date: January 2019
+KernelVersion: 5.0
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: write only
+ Writing a 1 to this file while sync_enable is set to 1 will
+ synchronize 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>/color/<led color>
+Date: January 2019
+KernelVersion: 5.0
+Contact: Dan Murphy <dmurphy@xxxxxx>
+Description: read/write
+ These files are dynamically created based on the colors defined
+ by the registrar of the class.
+ The led color(s) can be but not limited to red, green, blue,
+ white, amber and violet. 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>/max_brightness.
