Hi Felipe,
On 12/5/2018 1:15 AM, Felipe Balbi wrote:
> Hi,
>
> Thinh Nguyen <thinh.nguyen@xxxxxxxxxxxx> writes:
>> Implement the new frame_number API to report the isochronous interval
>> frame number. This patch checks and reports the interval in which the
>> isoc transfer was transmitted or received via the Isoc-First TRB SOF
>> number field.
>>
>> Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
>> ---
>> Change in v3:
>> - Implement the change with the redefined frame_number meaning
>> Change in v2:
>> - Capture frame number at request cleanup
>>
>> drivers/usb/dwc3/core.h | 1 +
>> drivers/usb/dwc3/gadget.c | 13 +++++++++++++
>> 2 files changed, 14 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
>> index ed0359d1216d..2c9f7a93147a 100644
>> --- a/drivers/usb/dwc3/core.h
>> +++ b/drivers/usb/dwc3/core.h
>> @@ -777,6 +777,7 @@ enum dwc3_link_state {
>> #define DWC3_TRB_CTRL_ISP_IMI BIT(10)
>> #define DWC3_TRB_CTRL_IOC BIT(11)
>> #define DWC3_TRB_CTRL_SID_SOFN(n) (((n) & 0xffff) << 14)
>> +#define DWC3_TRB_CTRL_GET_SID_SOFN(n) (((n) & (0xffff << 14)) >> 14)
>>
>> #define DWC3_TRBCTL_TYPE(n) ((n) & (0x3f << 4))
>> #define DWC3_TRBCTL_NORMAL DWC3_TRB_CTRL_TRBCTL(1)
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index 679c12e14522..2de563124fc1 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -2254,6 +2254,19 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep,
>> if (chain && (trb->ctrl & DWC3_TRB_CTRL_HWO))
>> trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
>>
>> + /*
>> + * For isochronous transfers, the first TRB in a service interval must
>> + * have the Isoc-First type. Track and report its interval frame number.
>> + */
>> + if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
>> + (trb->ctrl & DWC3_TRBCTL_ISOCHRONOUS_FIRST)) {
>> + unsigned int frame_number;
>> +
>> + frame_number = DWC3_TRB_CTRL_GET_SID_SOFN(trb->ctrl);
>> + frame_number &= ~(dep->interval - 1);
>> + req->request.frame_number = frame_number;
>> + }
> could you refresh my memory on how this is going to be used?
>
Sure. This informs the upper layer driver what interval the isoc request
went out. The users can use this information for applications that
require synchronization with the host.
Thinh
