[U-Boot] [PATCH 06/10] mx23_olinuxino: Add support for status LED

Marek Vasut
2013-01-30T16:05:21Z

Dear Otavio Salvador,

> On Wed, Jan 30, 2013 at 1:39 PM, Marek Vasut <marex@denx.de> wrote:
> > Dear Otavio Salvador,
> >
> >> On Wed, Jan 30, 2013 at 12:13 PM, Marek Vasut <marex@denx.de> wrote:
> >> > Dear Otavio Salvador,
> >> >
> >> >> This allow user to know if the bootloader is running, even without a
> >> >> serial console.
> >> >>
> >> >> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
> >> >
> >> > Uh oh, how does this know which GPIO to toggle to drive the led this
> >> > time ?
> >>
> >> The problem wasn't the code but me. I wasn't able to find the right
> >> GPIO number at that time.
> >
> > This is not my question. My question is how does this toggle the GPIO for
> > the LED?
>
> gpio_led driver (drivers/misc/gpio_led.c) does it.
>
> ...
> void __led_init(led_id_t mask, int state)
> {
> gpio_request(mask, "gpio_led");
> gpio_direction_output(mask, state == STATUS_LED_ON);
> }
>
> void __led_set(led_id_t mask, int state)
> {
> gpio_set_value(mask, state == STATUS_LED_ON);
> }
> ...

Ok, this didn't explain much to me.

> > Moreover, you never set the LED GPIO as output.
>
> The driver handles it by itself.

Oh ok.

Now that I did read through the code, I have few more questions:

Why can't STATUS_LED_BIT be the MX23_PAD_SSP1_DETECT__GPIO_2_1 now? Did you test
CMD_LED, does it work when toggling the LED?

Best regards,
Marek Vasut