Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
On 31/10/17 15:24, Felipe Balbi wrote:
> Roger Quadros <rogerq@xxxxxx> writes:
>
>> UDC core calls .udc_set_speed() with the speed parameter
>> containing the maximum speed supported by the gadget function
>> driver. This might very well be more or less than that
>> supported by the dwc3 controller driver.
>>
>> Select the lesser of the 2 speeds so both are operating
>> within limits.
>>
>> This fixes PHY Erratic errors and 2 second enumeration delay on
>> TI's AM437x platforms.
>>
>> Fixes: 7d8d0639565f ("usb: dwc3: gadget: implement ->udc_set_speed()")
>> Cc: <stable@xxxxxxxxxxxxxxx> # v4.13+
>> Reported-by: Dylan Howey <Dylan.Howey@xxxxxxxxxxxxx>
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
>> ---
>> drivers/usb/dwc3/gadget.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index f064f15..9f27ec0 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -2008,6 +2008,8 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
>> unsigned long flags;
>> u32 reg;
>>
>> + speed = min(g->max_speed, speed);
>
> should we do that in udc core itself?
>
> @@ -1080,8 +1080,12 @@ static inline void usb_gadget_udc_stop(struct usb_udc *udc)
> static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
> enum usb_device_speed speed)
> {
> - if (udc->gadget->ops->udc_set_speed)
> - udc->gadget->ops->udc_set_speed(udc->gadget, speed);
> + if (udc->gadget->ops->udc_set_speed) {
> + enum usb_device_speed s;
> +
> + s = min(speed, udc->gadget->max_speed);
> + udc->gadget->ops->udc_set_speed(udc->gadget, s);
> + }
> }
>
> /**
>
> then the fix applies for all UDCs.
>
Sounds like a good idea. Will re-spin this patch.
--
cheers,
-roger
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki