Hardware blink and brightness
Hi,
Is there any particular reason to stipulate, (hardware) blink should be turned off, when brightness is set to 0? Following is copied from "Documentation/leds/leds-class.txt"
"Setting the brightness to zero with brightness_set() callback function should completely turn off the LED and cancel the previously programmed hardware blinking function, if any."
The chip driver could also use other methods for the same, keeping brightness independent of blink.
For example, delay_on/off
delay_off=0 ==> blink off, led on.
delay_on=0 ==> blink off, led off.
Or am I overlooking something?
Many Thanks,
Tony
Hi Tony,
Quoted 7 lines · Tony Makkiel
Hi,
Is there any particular reason to stipulate, (hardware) blink should be turned off, when brightness is set to 0? Following is copied from "Documentation/leds/leds-class.txt""Setting the brightness to zero with
brightness_set()callback function should completely turn off the LED and cancel the previously programmed hardware blinking function, if any."
Quoted 7 lines
The chip driver could also use other methods for the same, keeping brightness independent of blink.
For example, delay_on/off
delay_off=0 ==> blink off, led on.
delay_on=0 ==> blink off, led off.Or am I overlooking something?
Setting brightness to zero not only disables blinking but also any other active trigger. Besides, would it make sense to have blinking enabled with brightness set to 0?
Anyway, we have to keep this interface as-is so as not to break existing users of the LED API.
Signature · 2 lines
Best regards, Jacek Anaszewski
Quoted 16 lines · Jacek Anaszewski
Hi Tony,
Quoted 13 lines · Tony Makkiel
Hi,
Is there any particular reason to stipulate, (hardware) blink should be turned off, when brightness is set to 0? Following is copied from "Documentation/leds/leds-class.txt""Setting the brightness to zero with
brightness_set()callback function should completely turn off the LED and cancel the previously programmed hardware blinking function, if any."The chip driver could also use other methods for the same, keeping brightness independent of blink.
For example, delay_on/off
delay_off=0 ==> blink off, led on.
delay_on=0 ==> blink off, led off.
Quoted 5 lines
Quoted 1 line
Or am I overlooking something?
Setting brightness to zero not only disables blinking but also any other active trigger. Besides, would it make sense to have blinking enabled with brightness set to 0?
I agree brightness set to 0, should turn off led. I was thinking of case when user turns led back ON with a brightness value. Ideally led comes back on blinking as was configured previously(making, brightness and blink independent). At present, once the brightness is set, blink also needs to be reconfigured.
Quoted 3 lines
Anyway, we have to keep this interface as-is so as not to break existing users of the LED API.
I see your point now, Thank you. I was under the wrong impression, this could be achieved without code change.
Initially, I thought of using delay_on/delay_off, to turn off blink. But with this approach, even if it will save a step initially (no need to reconfigure blink), will add additional step (re-enable trigger) to disable blink.