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

Otavio Salvador
2013-01-30T17:02:43Z

On Wed, Jan 30, 2013 at 2:15 PM, Marek Vasut <marex@denx.de> wrote:
> Dear Otavio Salvador,
>
>> On Wed, Jan 30, 2013 at 2:05 PM, Marek Vasut <marex@denx.de> wrote:
>> > 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?
>>
>> It can but than we need to include the iomux-mx23.h header. It in the
>> end is the same thing.
>
> In the end, when I read the code in two hours, I'll be wondering what this magic
> junk is. Thus, we will go for this and apply the adjustment for iomux.

So in the end you prefer me to use the MUX name? I am fine in doing it for v2.

--
Otavio Salvador O.S. Systems
E-mail: otavio at ossystems.com.br http://www.ossystems.com.br
Mobile: +55 53 9981-7854 http://projetos.ossystems.com.br