Re: [PATCH RESEND] LEDS-One-Shot-Timer-Trigger-implementation

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Tue, 2012-04-10 at 09:31 -0600, Shuah Khan wrote:
> On Tue, 2012-04-10 at 14:24 +0100, Richard Purdie wrote:
> > Having looked at the code and read through the thread and Andrew's patch
> > review, I'm left wondering why you didn't add a new trigger for this
> > functionality?
> 
> By new trigger do you mean, adding another interface to struct
> led_trigger. My first patch to solve this use-case indeed did that. I
> still happen to have a copy of that patch. It would require more changes
> to the infrastructure than this approach, however it is more explicit
> and clear.
> 
> static struct led_trigger gpio_led_trigger = {
>        .name           = "gpio",
> +       .activate_once  = NULL,
>        .activate       = gpio_trig_activate,
>        .deactivate     = gpio_trig_deactivate,
> };

No, I did not mean adding another interface. Why can't we have a trigger
which just triggers once and then stops? It would be similar to the
timer trigger but with a different name and way of operating.

> > Dimity raises some valid questions about the force-feedback framework in
> > the input system too. We need to make a decision about where phone
> > vibration framework belongs and then stick to that. You can argue this
> > to either subsystem, neither "led" or "input" is a obvious description
> > of phone vibration at a first glance!
> 
> force-feedback framework is another alternative. Making a decision is
> great, what are the next steps to get closer to making a call? 

I'd first like to understand why this couldn't be a separate trigger,
then we can understand the alternatives we're comparing.

Cheers,

Richard