Re: [GIT PULL] LED updates

Richard Purdie wrote:
On Thu, 2008-02-07 at 19:38 -0200, Henrique de Moraes Holschuh wrote:
On Thu, 07 Feb 2008, Richard Purdie wrote:
Márton Németh:
leds: Add support for hardware accelerated LED flashing
leds: hw acceleration for Clevo mail LED driver
This one has a loose end: when you call brightness_set on a led with
hardware flash acceleration, you will leave the trigger armed, BUT the led
won't blink anymore. That's just wrong.

Agreed.

My only question is that do you know any LED hardware which can blink _and_
can set the brightness independently? If there would be such a LED I could
imagine that the brightness can be changed while the LED remains blinking at
some low frequency. For example a simple LED with brightness set possibility and
blinking directed by software is an example where the blinking and the brightness
setting are completely independent.

I agree, however, that if the brightness is set to LED_OFF, the trigger
should be also removed.

Either we should always remove *any* (hardware accelerated or not!) active
trigger when a write to brightness_set is done, or the stuff about "calling
brightness_set will disable the hardware accelerated blink" has to go.

I personally prefer that we would always remove any active trigger if
brightness_set is to be called. IMHO, it is neater, and it is also the
least-surprise-behaviour from an user perspective with the LED_OFF:LED_FULL
triggers we have right now.

Even without the hardware acceleration, a user write to set_brightness
leaves any active trigger active and isn't really intuitive or right
either.

Which one will be? If it is "remove any active trigger", I'd not mind
writing the patch.

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