Messages in this thread | | | Subject | Re: led: hw-trigger, global brightness and multi-colored leds | From | Uwe Kleine-König <> | Date | Thu, 3 May 2018 20:49:54 +0200 |
| |
Hello Pavel,
On 05/02/2018 11:21 PM, Pavel Machek wrote: >> on the Turris Omnia[1] the LEDs are controllable via an i2c device. Each >> LED can be either in "manual mode" or in a mode I'd call "native mode" >> which is the default. In this native mode the LED being on or off >> depends on an input line that is controlled by another hardware. So a >> LED signals for example activity on the WAN ethernet port without any >> software intervention, but can be used as a normal LED, too, when in >> "manual mode" where it can be switched on and off by a register >> write. > > "Native mode" is quite common. We have it for example on Nokia N900 > here (charger has hw option to automatically control the LED).
git grep -i n900 -- drivers/leds doesn't yield any output. Do I miss anything?
> I believe reasonable solution would be to have "hardware" trigger, and > have it selected by default. When active, LED would be controlled by > hardware.
There is no prior art for that available as source code, right?
>> Another feature of the LED device is that there is a global brightness >> register that influences all LED's brightness (if on) independent of the >> operating mode. > > We can't describe that easily.
Given that I can give an RGB value (i.e. 3x 8 bit) for the LED, I can change brightness per LED. Have to play around a bit.
>> Further the color of each LED can be set to an RGB triplet. > > We normally handle RGB LED as three independend LEDs, like > notify::red, notify::green, notify::blue. Again, example is Nokia N900 > or Motorola Droid 4.
I cannot find source code for LEDs on the Droid 4 either.
An ugly property here is that the hardware trigger only operates on all three colors at once. Hmm, will think a bit about the way to go.
Best regards and thanks for your input, Uwe
[unhandled content-type:application/pgp-signature] | |