Hi,
On 12/10/2018 2:04 PM, Felipe Balbi wrote:
> Tejas Joglekar <tejas.joglekar@xxxxxxxxxxxx> writes:
>
>> In stream mode, when fast-forwarding TRBs, the stream number
>> is not cleared causing the new stream to not get assigned. So
>> we don't want controller to carry on transfers when short packet
>> is received. So disable the CSP for stream capable endpoint.
>>
>> This is based on the 3.30a Programming guide, where table 3-1
>> device descriptor structure field definitions says for CSP bit
>> If this bit is 0, the controller generates an XferComplete event
>> and remove the stream. So if we keep CSP as 1 then switching between
>> streams would not happen as in stream mode, when fast-forwarding
>> TRBs, the stream number is not cleared causing the new stream to not get
>> assigned.
>>
>> Signed-off-by: Tejas Joglekar <joglekar@xxxxxxxxxxxx>
>> ---
>> drivers/usb/dwc3/gadget.c | 10 ++++++++--
>> 1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index f1089ec..0d2afc1 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -986,9 +986,15 @@ static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb,
>> usb_endpoint_type(dep->endpoint.desc));
>> }
>>
>> - /* always enable Continue on Short Packet */
>> + /*
>> + * Enable Continue on Short Packet
>> + * when endpoint is not a stream capable
>> + */
>> if (usb_endpoint_dir_out(dep->endpoint.desc)) {
>> - trb->ctrl |= DWC3_TRB_CTRL_CSP;
>> + if (dep->stream_capable)
>> + trb->ctrl &= ~DWC3_TRB_CTRL_CSP;
> Is this necessary? Or would it be enough to have this as:
Yeah this is enough... I will send the v2
>
> if (!dep->stream_capable)
> trb->ctrl |= DWC3_TRB_CTRL_CSP;
>
Regards,
Tejas Joglekar
