Re: [PATCH] usb: dwc3: leave default DMA for PCI devices

[Hans de Goede]

Hi,

On 11/13/21 15:29, Fabio Aiuto wrote:
> in case of a PCI dwc3 controller, leave the default DMA
> mask. Calling of a 64 bit DMA mask breaks the driver on
> cherrytrail based tablets like Cyberbook T116.
> 
> Fixes: 45d39448b4d0 ("usb: dwc3: support 64 bit DMA in platform driver")
> Reported-by: Hans De Goede <hdegoede@xxxxxxxxxx>
> Tested-by: Fabio Aiuto <fabioaiuto83@xxxxxxxxx>
> Signed-off-by: Fabio Aiuto <fabioaiuto83@xxxxxxxxx>

I can confirm that this fixes things for me to:

Tested-by: Hans de Goede <hdegoede@xxxxxxxxxx>

Regards,

Hans




> ---
>  drivers/usb/dwc3/core.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 643239d7d370..f4c09951b517 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1594,9 +1594,11 @@ static int dwc3_probe(struct platform_device *pdev)
>  
>  	dwc3_get_properties(dwc);
>  
> -	ret = dma_set_mask_and_coherent(dwc->sysdev, DMA_BIT_MASK(64));
> -	if (ret)
> -		return ret;
> +	if (!dwc->sysdev_is_parent) {
> +		ret = dma_set_mask_and_coherent(dwc->sysdev, DMA_BIT_MASK(64));
> +		if (ret)
> +			return ret;
> +	}
>  
>  	dwc->reset = devm_reset_control_array_get_optional_shared(dev);
>  	if (IS_ERR(dwc->reset))
>