Hello Robert,

Thanks for the reply. Essentially, I've been looking through all of that
for the last week or so ( off an on ). I Kind of got stuck on stuff like
this:

gpios = <&gpio1 21 GPIO_ACTIVE_HIGH>;

Ok, so this whole line makes complete sense to me, except the variable that
is being assigned. I have not been able to find any information on this
yet. Somewhere there was a mention to the gpio.h header file, but that file
only has two defines that can not possibly tell me what the variable
"gpios" *is*.

My end goal however is just to use the USR LEDs, but I want explicit
control of the LEDs for my app, so Linux is not "confused". At the same
time, I was hoping to avoid changing stock files if at all possible.

Is this possible, or will I have to modify the board files no matter what ?

On Thu, Nov 19, 2015 at 6:43 PM, Robert Nelson <[email protected]>
wrote:

> On Thu, Nov 19, 2015 at 7:36 PM, William Hermans <[email protected]>
> wrote:
> > So, I'm wondering with a hardware resource, that is "claimed" through the
> > main board device tree file. Such as the on board USR LEDs. What is the
> > proper way to reclaim these pins, so they can be used for a different
> > purpose ?
>
> They are claimed here:
>
>
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/am335x-bone-common.dtsi#n21
>
> via:
>
> pinctrl-0 = <&user_leds_s0>;
> &
> gpios = <&gpio1 21 GPIO_ACTIVE_HIGH>;
> gpios = <&gpio1 22 GPIO_ACTIVE_HIGH>;
> gpios = <&gpio1 23 GPIO_ACTIVE_HIGH>;
> gpios = <&gpio1 24 GPIO_ACTIVE_HIGH>;
>
> Whereas this define, doesn't 'claim' them, it just set's up a struct
> to be utiilzed by above ^^
>
> user_leds_s0: user_leds_s0 {
>         pinctrl-single,pins = <
>                  0x54 (PIN_OUTPUT_PULLDOWN | MUX_MODE7) /*
> gpmc_a5.gpio1_21 */
>                 0x58 (PIN_OUTPUT_PULLUP | MUX_MODE7) /* gpmc_a6.gpio1_22 */
>                 0x5c (PIN_OUTPUT_PULLDOWN | MUX_MODE7) /* gpmc_a7.gpio1_23
> */
>                 0x60 (PIN_OUTPUT_PULLUP | MUX_MODE7) /* gpmc_a8.gpio1_24 */
>         >;
> };
>
> Regards,
>
> --
> Robert Nelson
> https://rcn-ee.com/
>
> --
> For more options, visit http://beagleboard.org/discuss
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