On Sun, May 05, 2024 at 07:54:36PM +0200, Simon Holesch wrote: > On Sun May 5, 2024 at 5:31 PM CEST, Hongren Zheng wrote: > > On Sun, Dec 17, 2023 at 08:30:40PM +0100, Simon Holesch wrote: > > > Skip submitting URBs, when identical requests were already sent in > > > tweak_special_requests(). Instead call the completion handler directly > > > to return the result of the URB. > > > > Reproduced the behavior and this patch fixed the bahavior > > Thank you for testing. > > > > @@ -468,6 +477,7 @@ static void stub_recv_cmd_submit(struct stub_device *sdev, > > > int support_sg = 1; > > > int np = 0; > > > int ret, i; > > > + int is_tweaked; > > > > > > if (pipe == -1) > > > return; > > > @@ -580,8 +590,7 @@ static void stub_recv_cmd_submit(struct stub_device *sdev, > > > priv->urbs[i]->pipe = pipe; > > > priv->urbs[i]->complete = stub_complete; > > > > > > - /* no need to submit an intercepted request, but harmless? */ > > > - tweak_special_requests(priv->urbs[i]); > > > + is_tweaked = tweak_special_requests(priv->urbs[i]); > > > > One question though, if there are mutiple urbs and one of them is > > SET CONFIGURATION, then all of them would not be submitted, > > as is_tweaked is a *global* flag instead of a per-urb flag. > > > > Now it is assumed that when the urb is SET CONFIGURATION then > > num_urbs is 1. I assume it just happens to be the case and I do > > not know if it holds for all scenario. > > To be honest, I didn't fully understand the num_urbs > 1 case. I assumed > this is for drivers not supporting SG and a long URB is just broken up > into multiple ones. I misunderstood that code path. It is indeed multiple URBs for one PDU when the host controller for the physical device does not support SG. And one global is_tweaked flag is enough. I think adding a comment here would make it easier to understand. Reviewed-By: Hongren Zheng <i@xxxxxxxxxxx> Tested-By: Hongren Zheng <i@xxxxxxxxxxx>
