Hi,

Roman Kapl wrote:
> The address should be set to zero during reset according to the
> documentation.

That is for usb reset and not core soft reset, and dwc3 already handles 
that case.

> Clearing RunStop ensures that the host disconnects from
> the device (it was not cleared by CSFTRST, at least on ls1043).
>
> This allows the dwc3 to properly initialize even if the previous
> driver did not shutdown the device (e.g. when using virtualization).

This sounds like a workaround to some issue that the function driver did 
not handle.

> Signed-off-by: Roman Kapl <r...@sysgo.com>
> ---
>   drivers/usb/dwc3/core.c | 5 +++++
>   1 file changed, 5 insertions(+)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index c9bb93a2c81e..c633f5e0621d 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -250,6 +250,7 @@ static int dwc3_core_soft_reset(struct dwc3 *dwc)
>   
>       reg = dwc3_readl(dwc->regs, DWC3_DCTL);
>       reg |= DWC3_DCTL_CSFTRST;
> +     reg &= ~DWC3_DCTL_RUN_STOP;
>       dwc3_writel(dwc->regs, DWC3_DCTL, reg);
>   
>       do {
> @@ -266,6 +267,10 @@ static int dwc3_core_soft_reset(struct dwc3 *dwc)
>       return -ETIMEDOUT;
>   
>   done:
> +     reg = dwc3_readl(dwc->regs, DWC3_DCFG);
> +     reg &= ~(DWC3_DCFG_DEVADDR_MASK);
> +     dwc3_writel(dwc->regs, DWC3_DCFG, reg);
> +
>       /*
>        * For DWC_usb31 controller, once DWC3_DCTL_CSFTRST bit is cleared,
>        * we must wait at least 50ms before accessing the PHY domain

BR,
Thinh

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