Re: Iwlwifi and LEDS?

[Johannes Berg <johannes@sipsolutions.net>]

On Fri, 2010-05-28 at 15:58 +0100, Richard Purdie wrote:

> > The proper way to do this now would be to rewrite the LED code in
> > iwlwifi to:
> > 
> > 1) register an LED again, which implements the blink_set() callback and
> > programs the hw accordingly. This is essentially implementing
> > iwl_led_pattern(), but with on_time/off_time parameters.
> > 
> > 2) Convert the current caller of iwl_led_pattern() to be an LED trigger
> > that registers with the LED system. It would call the blink_set() for
> > the LED it is connected to. Ideally, there should be some common
> > software emulation if the LED has no blink_set(). Richard, is there a
> > "make LED blink" callback that would start a timer for that LED? The
> > timer trigger uses it but doesn't seem to be usable itself for other
> > triggers?
> > 
> > 3) start the LED on device start, stop it on device stop
> > 
> > 4) depending on the module's led_mode, connect the LED to the
> > appropriate default trigger, e.g. mac80211's assoc trigger or normally
> > of course the new iwlwifi-blink trigger.
> 
> I have to admit I don't fully understand what the capabilities of your
> hardware are.

Sorry, I didn't mean to confuse you with the hardware details. The
hardware can blink, essentially.

> Certainly registering a trigger with the LED system, maybe only
> appearing for this specific hardware sounds like the way to go. Since
> this will only appear as a trigger for this hardware, the trigger can
> then poke whatever it needs into the hardware to work as a traffic
> indication?

Yes, that would be one way. However, that would seem to unduly restrict
the trigger's use. It can be used with any LED that has a blink_set()
callback since it doesn't need to poke the hardware directly.

What I was wondering is if there is (or should be) a common "blink
emulation" for LEDs that don't have a blink_set, so instead of calling
	led->blink_set(...)
I would call
	led_blink_set(...)
and that would start the timer etc.

johannes