hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

usb: dwc3: gadget: Allow restarting a transfer 

It's possible that there's no new TRBs prepared when kicking a transfer.
This happens when we need to stop and restart a transfer such as in the
case of reinitiating a stream or retrying isoc transfer. For streams,
sometime host may reject a stream and the device may need to reinitiate
that stream by stopping and restarting a transfer. In this case, all the
TRBs may have already been prepared. Allow the function
__dwc3_gadget_kick_transfer() to go through even though there's no new
TRB.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
This commit is contained in:
Thinh Nguyen 2020-09-29 00:18:48 -07:00 committed by Felipe Balbi
parent a73abc28ce
commit d72ecc08de
1 changed files with 6 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/usb/dwc3/gadget.c
View File

@ -1326,8 +1326,13 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
int ret;
u32 cmd;
/*
* Note that it's normal to have no new TRBs prepared (i.e. ret == 0).
* This happens when we need to stop and restart a transfer such as in
* the case of reinitiating a stream or retrying an isoc transfer.
*/
ret = dwc3_prepare_trbs(dep);
if (ret <= 0)
if (ret < 0)
return ret;
starting = !(dep->flags & DWC3_EP_TRANSFER_STARTED);