Re: [BUG] pinctrl: reg-fixed-voltage usb0-vbus: error -EINVAL: can't get GPIO

[Hans Verkuil <hverkuil-cisco@xxxxxxxxx>]

On 18/01/2022 15:13, Hans Verkuil wrote:
> On 1/18/22 13:50, Corentin Labbe wrote:
>> Hello
>>
>> As reported on old googlegroup sunxi mainling list, on linux-next-20220118, USB storage fail to bring up on orangepiPC.
>> We can see some error logs in dmesg:
>> reg-fixed-voltage usb0-vbus: error -EINVAL: can't get GPIO
>> reg-fixed-voltage: probe of usb0-vbus failed with error -22
>>
>> This is bisected to: 8df89a7cbc63c7598c00611ad17b67e8d5b4fad3 pinctrl-sunxi: don't call pinctrl_gpio_direction()
>>
>> Reverting this commit lead to a working USB storage being setuped.

Hopefully this is resolved by this patch:

https://patchwork.linuxtv.org/project/linux-media/patch/0f536cd8-01db-5d16-2cec-ec6d19409a49@xxxxxxxxx/

Please test!

Regards,

	Hans

> 
> Hmm, I'll bet it's EPROBE_DEFER related.
> 
> The original call (pre that commit) of pinctrl_gpio_direction_output() checks
> if the pin controller could find the pin (pinctrl_get_device_gpio_range()).
> 
> That doesn't happen in the new code.
> 
> The sunxi appears to have two pincontrollers in the device tree (&pio and &r_pio),
> that might be part of the reason this is an issue here.
> 
> Linus, should there be a check somewhere for a missing pincontroller in
> gpiod_get_index()? I suspect that before my commit it was the gpiod_configure_flags
> call in that function that returned -EPROBE_DEFER, but I'm not completely certain.
> 
> If someone can give me a hint about what should be done, then I can make a patch.
> 
> The alternative is to revert this sunxi patch, but perhaps this is a deeper
> problem with these pincontroller drivers that set the direction directly
> instead of going through pinctrl_gpio_direction_output().
> 
> Corentin, it would help me if you can figure out where the EPROBE_DEFER is
> returned (pre-commit) in drivers/pinctrl/core.c. Probably pinctrl_get_device_gpio_range().
> 
> And I'd love to have the WARN_ON(1) output from just before the 'return -EPROBE_DEFER'.
> 
> Regards,
> 
> 	Hans
> 
>>
>> Regards