Re: [PATCH] usb: dwc3: core: disable 3.0 clock when operating in 2.0 device mode

[Greg KH]

On Thu, Oct 05, 2023 at 03:57:25PM +0530, Piyush Mehta wrote:
> The GUCTL1.DEV_FORCE_20_CLK_FOR_30_CLK bit enable the feature of internal
> 2.0(utmi/ulpi) clock to be routed as the 3.0 (pipe) clock. This feature is
> applicable when core is operating in 2.0 device mode.
> 
> When this bit is set in host mode and core is in 2.0 device mode (maximum
> speed = high-speed) then usb super speed devices not detected on host.
> 
> To address the above issue added usb device mode conditional check.
> 
> Fixes: 62b20e6e0dde ("usb: dwc3: core: do not use 3.0 clock when operating in 2.0 mode")
> Signed-off-by: Piyush Mehta <piyush.mehta@xxxxxxx>
> ---
> DWC3 Register Map Link:
> https://docs.xilinx.com/r/en-US/ug1087-zynq-ultrascale-registers/GUCTL1-USB3_XHCI-Register
> Register Name	GUCTL1
> Bit: 26 
> Bit Name: DEV_FORCE_20_CLK_FOR_30_CLK
> ---
>  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 9c6bf054f15d..0cf1fe60628b 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1202,6 +1202,7 @@ static int dwc3_core_init(struct dwc3 *dwc)
>  			reg |= DWC3_GUCTL1_PARKMODE_DISABLE_HS;
>  
>  		if (DWC3_VER_IS_WITHIN(DWC3, 290A, ANY) &&
> +		    (dwc->dr_mode == USB_DR_MODE_PERIPHERAL) &&
>  		    (dwc->maximum_speed == USB_SPEED_HIGH ||
>  		     dwc->maximum_speed == USB_SPEED_FULL))
>  			reg |= DWC3_GUCTL1_DEV_FORCE_20_CLK_FOR_30_CLK;
> -- 
> 2.17.1
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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- You have marked a patch with a "Fixes:" tag for a commit that is in an
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If you wish to discuss this problem further, or you have questions about
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thanks,

greg k-h's patch email bot