The .dtb file is about the device tree. It doesn't matter the device driver
is built-in, or a loadable module. Is it right?

Thanks,

On Mon, Sep 7, 2015 at 12:11 PM, RJ Wang <[email protected]> wrote:

> Thanks Robert. In am335x-evmsk.dts, there is leds definition:
>
>
>     leds {
>         pinctrl-names = "default", "sleep";
>         pinctrl-0 = <&user_leds_default>;
>         pinctrl-1 = <&user_leds_sleep>;
>
>         compatible = "gpio-leds";
>
>         led@1 {
>             label = "evmsk:green:usr0";
>             gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
>             default-state = "off";
>         };
>
>         led@2 {
>             label = "evmsk:green:usr1";
>             gpios = <&gpio1 5 GPIO_ACTIVE_HIGH>;
>             default-state = "off";
>         };
>
>         led@3 {
>             label = "evmsk:green:mmc0";
>             gpios = <&gpio1 6 GPIO_ACTIVE_HIGH>;
>             linux,default-trigger = "mmc0";
>             default-state = "off";
>         };
>
>         led@4 {
>             label = "evmsk:green:heartbeat";
>             gpios = <&gpio1 7 GPIO_ACTIVE_HIGH>;
>             linux,default-trigger = "heartbeat";
>             default-state = "off";
>         };
>     };
>
> On this board, there is no gpio when running lsmod. Does this .dts file
> tell me something?
> I am new to this topic.
>
> *Just actually look at the kernel dts file for you board.*
>
> The above leds in .dts tells me something?
>
> Thanks,
>
>
> On Mon, Sep 7, 2015 at 11:05 AM, Robert Nelson <[email protected]>
> wrote:
>
>>
>> On Sep 7, 2015 9:32 AM, "RJ Wang" <[email protected]> wrote:
>> >
>> > On link
>> > https://www.kernel.org/doc/Documentation/gpio/sysfs.txt
>> > it is talked about gpio
>> >
>> > It has comments:
>> >
>> > Note that standard kernel drivers exist for common "LEDs and Buttons"
>> > GPIO tasks:  "leds-gpio" and "gpio_keys", respectively. Use those
>> > instead of talking directly to the GPIOs; they integrate with kernel
>> > frameworks better than your userspace code could.
>> >
>> >
>> > What category does GPIO in BeagleBone Black belong to?
>>
>> Led-gpio
>>
>> >
>> > What is about the built-in GPIO in my AM3358 SK board?
>>
>> Just actually look at the kernel dts file for you board.
>>
>> Regards,
>>
>> --
>> For more options, visit http://beagleboard.org/discuss
>> ---
>> You received this message because you are subscribed to a topic in the
>> Google Groups "BeagleBoard" group.
>> To unsubscribe from this topic, visit
>> https://groups.google.com/d/topic/beagleboard/GoYJdV9MI3c/unsubscribe.
>> To unsubscribe from this group and all its topics, send an email to
>> [email protected].
>> For more options, visit https://groups.google.com/d/optout.
>>
>
>

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/d/optout.

Reply via email to