# how to fix PWM tunable name to ehrpwm.1



## Nicola Mingotti (Jun 1, 2019)

Hi,

In my Beablebone Black, FreeBSD-12, i created two overlays, pwm.dtso and pwm1.dtso. They enable the PWM pin p9.21, p9.22 and respectively p9.14, p9.16.  DTSO files are below.

If I load both the DTBOs at boot I see correctly `ehrpwm.0` and `ehrpwm.1`, associated to the correct pins. But, if i remove the overlay `pwm.dtbo` then i seen only `ehrpwm.0` in `sysctl -a`, which is not what i want, i would like to see the name `ehrpwm.1`.

This is important because i must be 100% sure a certain pin correspond the a certain tunable. I guess there must be some parameter in the DTSO wich i don't know, i hope you can give me some directions. 

bye
n.

File pwm.dtso:

```
/dts-v1/;
/plugin/;

/ {
    compatible = "ti,am335x-bone-black", "ti,am335x-bone", "ti,am33xx";
    exclusive-use = "P9.21","P9.22","ehrpwm0_AB";
};

&am33xx_pinmux {
     ehrpwm0_AB_pins: pinmux_ehrpwm0_AB_pins {
        pinctrl-single,pins = <
             0x154 0x03        /* P9.21 */
             0x150 0x03        /* P9.22 */
        >;
    };
};

&ehrpwm0 {
    status = "okay";
    pinctrl-names = "default";
    pinctrl-0 = <&ehrpwm0_AB_pins>;
};

&epwmss0 {
   status = "okay";
};

&ecap0 {
   status = "okay";
};
```

And pwm1.dtso

```
/dts-v1/;
/plugin/;

/ {
    compatible = "ti,am335x-bone-black", "ti,am335x-bone", "ti,am33xx";
    exclusive-use = "P9.14","P9.16","ehrpwm1_AB";
};

&am33xx_pinmux {
     ehrpwm1_AB_pins: pinmux_ehrpwm1_AB_pins {
        pinctrl-single,pins = <
             0x048 0x06        /* P9.14 */
             0x04C 0x06        /* P9.16 */
        >;
    };
};

&ehrpwm1 {
    status = "okay";
    pinctrl-names = "default";
    pinctrl-0 = <&ehrpwm1_AB_pins>;
};

&epwmss1 {
   status = "okay";
};

&ecap1 {
   status = "okay";
};
```


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