JetPack5.1 pwm-fan regulator is not work normally

[ultwcz1997]

Hi everyone,
I am using my custom carried board and use a GPIO to control the PWM signal(low active, the PWM signal is not pulled low now). This GPIO is controlled by a regulator’s gpio terms. It has worked in Jetpack4.6. But when i upgraded JetPack5.1, the regulator seems not to work correctly.

regulator DTS is here

fixed-regulators {
    p3509_vdd_fan: regulator@111 {
        gpio = <&tegra_main_gpio TEGRA194_MAIN_GPIO(Q, 6) GPIO_ACTIVE_HIGH>;
        enable-active-low;
    };
};

but when i use cat /sys/kernel/debug/gpio

it always shows out hi ACTIVE LOW, not change status though the PWM is output

So what should i do when updating to JetPack5.1

Thank you.
Best Regards,
Ultwcz1997.

[KevinFFF]

Hi ultwcz1997,

Are you using the devkit or custom board for Xavier NX?
Could you help to verify with JP5.1.1(R35.3.1)?

Have you configured this GPIO as PWM usage through pinmux spreadsheet?

[ultwcz1997]

Hi @KevinFFF,
Are you using the devkit or custom board for Xavier NX?

custom board for Xavier NX

Could you help to verify with JP5.1.1(R35.3.1)?

yes, now it is the latest.

Have you configured this GPIO as PWM usage through pinmux spreadsheet?

No, i used PQ6 as a normal GPIO to output low or high.

[ultwcz1997]

Hi @KevinFFF ,
It used pwm-fan.c in driver/hwmon ,

So what should i do to set the correct DTS settings?

Thank you.

[KevinFFF]

@ultwcz1997

when i upgraded JetPack5.1

@ultwcz1997

yes, now it is the latest.

Please use JP5.1.1(R35.3.1) instead of JP5.1(R35.2.1) to verify.

I found the default pin for pwm-fan is GPIO14(PH.01).
Could you verify if it would work w/o any changes in pinmux or device tree?

[ultwcz1997]

Hi @KevinFFF
The problem was pwm-fan driver is changed, and now i changed DTS, vdd-fan-supply > fan-supply

pwm-fan {
    fan-supply = <&p3509_vdd_fan>;
};

fixed-regulators {
    p3509_vdd_fan: regulator@111 {
        gpio = <&tegra_main_gpio TEGRA194_MAIN_GPIO(Q, 6) GPIO_ACTIVE_LOW>;
        enable-active-low;
    };
};

Now GPIOQ6 is changed to LOW when pwm output, but when PWM’s duty is 0, the GPIOQ6 was still LOW, expect HIGH.

I think that the regulator_disable() function does not work.

[kayccc]

Sorry for the late response, is this still an issue to support? Thanks

[ultwcz1997]

It is resolved because the PWM driver changed in JetPack5.1.1

I’m sorry to forget it.