Re: [PATCH] driver/usb/dwc3: Add error handle for dwc3 get usb phy

[Felipe Balbi <balbi@kernel.org>]

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Hi,

Yuan Fang <fangyuanseu@gmail.com> writes:

> Add error handle for dwc3 core get usb phy, because
> without error handle will lead to bug.
>
> consider case like this, when both dwc->usb2_phy/usb3_phy
> and dwc->usb2_generic_phy/usb3_generic_phy do not exist
> current driver code set them all to NULL and return 0
> to caller which means usb phy is ready.

it's unclear what the problem is. Care to describe what's happening?

> Signed-off-by: Yuan Fang <yuan.fang@verisilicon.com>
> ---
> Hi maintainer,
>
>    I find this issue when i try to add a new usb phy driver for
>    dwc3 usb core, this issue looks like a bug, please kindly have
>    a review, many thanks.
>
> Best regards,
> Yuan Fang
>
>  drivers/usb/dwc3/core.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index b6e53d8212cd..4d527d313a4c 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1184,6 +1184,7 @@ static int dwc3_core_get_phy(struct dwc3 *dwc)
>  		ret = PTR_ERR(dwc->usb3_generic_phy);
>  		if (ret == -ENOSYS || ret == -ENODEV) {
>  			dwc->usb3_generic_phy = NULL;
> +			return dev_err_probe(dev, ret, "no usb phy device\n");

no, this is incorrect. Some platforms don't require a PHY driver at
all because there's no SW control for the PHY.

Moreover, generic PHY framework protects against NULL phy. I don't see
what the problem you're referring to is here.

-- 
balbi

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