Have you read this ?

https://github.com/beagleboard/bb.org-overlays

What version dtc are you using ? it must be 1.4.1 or greater.

On Sun, Aug 23, 2015 at 2:06 PM, M@ Dunlap <[email protected]> wrote:

> Hello all, I'm trying with increasing desperation to get my BBB (that is
> running 4.1.4-1-ARCH) to use a PWM.  It used to work, but then I updated
> from 3.8 to 4.1 and now it's back to SNAFU.  I'm trying to get device trees
> to work, but I really, really don't get device tree overlays, I've read all
> the guides/docs and am still clueless.
>
> My current best guess is to first load
> https://github.com/ProjectHexapod/bbbStuff/blob/master/overlays/am33xx_pwm-00A0.dts
> to activate pwm, and then load
> https://github.com/ProjectHexapod/bbbStuff/blob/master/overlays/thigh_bone-00A0.dts
> to configure all the pins.  Unfortunately when I do that and then try to
> echo something into pwmFolder/duty it tells me that the permission is
> denied.  I also don't understand why those need to be separate device tree
> overlays.
>
> In attempting to isolate the problem I also came up with the following,
> but it gives the same permission denied errors.  I'm out of ideas, please
> send help!  Also, even if you don't know how to solve the problem, I'd also
> be interested to hear if there are style or high-level problems with my
> approach....
>
> /dts-v1/;
> /plugin/;
>
> / {
>   compatible = "ti,beaglebone", "ti,beaglebone-black";
>
>   /* identification */
>   part-number = "test1";
>   version = "00A0";
>   exclusive-use =
>     /* the pin header uses */
>     "P8.13",
>     /* the hardware IP uses */
>     "ehrpwm2B";
>
>   fragment@0 {
>     target = <&epwmss0>;
>     __overlay__ {
>       status = "okay";
>     };
>   };
>
>   fragment@1 {
>     target = <&ehrpwm0>;
>     __overlay__ {
>       status = "okay";
>     };
>   };
>
>   fragment@2 {
>     target = <&epwmss1>;
>     __overlay__ {
>       status = "okay";
>     };
>   };
>
>   fragment@3 {
>     target = <&ehrpwm1>;
>     __overlay__ {
>       status = "okay";
>     };
>   };
>
>   fragment@4 {
>     target = <&epwmss2>;
>     __overlay__ {
>       status = "okay";
>     };
>   };
>
>   fragment@5 {
>     target = <&ehrpwm2>;
>     __overlay__ {
>       status = "okay";
>     };
>   };
>
> fragment@6 {
>     target = <&am33xx_pinmux>;
>     __overlay__ {
>       bs_pwm_P8_13_0x14: pinmux_bs_pwm_P8_13_0x14 {
>         pinctrl-single,pins = <0x024 0x14>;
>       };
>     };
>   };
>
>   fragment@7 {
>     target = <&ocp>;
>     __overlay__ {
>       bs_pwm_test_P8_13 {
>         compatible  = "pwm_test";
>         pwms    = <&ehrpwm2 1 500000 1>;
>         pwm-names   = "PWM_P8_13";
>
>         pinctrl-names = "default";
>         pinctrl-0 = <&bs_pwm_P8_13_0x14>;
>
>         enabled   = <1>;
>         duty    = <0>;
>         status    = "okay";
>       };
>     };
>   };
> };
>
> --
> 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.
>

-- 
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