> -----Original Message----- > From: John Youn [mailto:John.Youn@xxxxxxxxxxxx] > Sent: August-25-15 2:52 PM > To: Scott Branden; John Youn; Greg Kroah-Hartman; linux- > usb@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx; bcm-kernel-feedback-list; Roman Bacik > Subject: Re: [PATCH 1/1] usb: dwc2: gadget: parity fix in isochronous mode > > On 8/18/2015 8:45 AM, Scott Branden wrote: > > From: Roman Bacik <rbacik@xxxxxxxxxxxx> > > > > USB OTG driver in isochronous mode has to set the parity of the > > receiving microframe. The parity is set to even by default. This > > causes problems for an audio gadget, if the host starts transmitting on odd > microframes. > > > > This fix uses Incomplete Periodic Transfer interrupt to toggle between > > even and odd parity until the Transfer Complete interrupt is received. > > > > Signed-off-by: Roman Bacik <rbacik@xxxxxxxxxxxx> > > Reviewed-by: Abhinav Ratna <aratna@xxxxxxxxxxxx> > > Reviewed-by: Srinath Mannam <srinath.mannam@xxxxxxxxxxxx> > > Reviewed-by: Scott Branden <sbranden@xxxxxxxxxxxx> > > Signed-off-by: Scott Branden <sbranden@xxxxxxxxxxxx> > > --- > > drivers/usb/dwc2/core.h | 1 + > > drivers/usb/dwc2/gadget.c | 48 > ++++++++++++++++++++++++++++++++++++++++++++++- > > drivers/usb/dwc2/hw.h | 1 + > > 3 files changed, 49 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index > > 0ed87620..954d1cd 100644 > > --- a/drivers/usb/dwc2/core.h > > +++ b/drivers/usb/dwc2/core.h > > @@ -150,6 +150,7 @@ struct s3c_hsotg_ep { > > unsigned int periodic:1; > > unsigned int isochronous:1; > > unsigned int send_zlp:1; > > + unsigned int parity_set:1; > > > > char name[10]; > > }; > > diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c > > index 4d47b7c..28e4393 100644 > > --- a/drivers/usb/dwc2/gadget.c > > +++ b/drivers/usb/dwc2/gadget.c > > @@ -1954,6 +1954,8 @@ static void s3c_hsotg_epint(struct dwc2_hsotg > *hsotg, unsigned int idx, > > ints &= ~DXEPINT_XFERCOMPL; > > > > if (ints & DXEPINT_XFERCOMPL) { > > + if (hs_ep->isochronous && !hs_ep->parity_set) > > + hs_ep->parity_set = 1; > > if (hs_ep->isochronous && hs_ep->interval == 1) { > > if (ctrl & DXEPCTL_EOFRNUM) > > ctrl |= DXEPCTL_SETEVENFR; > > @@ -2316,7 +2318,8 @@ void s3c_hsotg_core_init_disconnected(struct > dwc2_hsotg *hsotg, > > GINTSTS_CONIDSTSCHNG | GINTSTS_USBRST | > > GINTSTS_RESETDET | GINTSTS_ENUMDONE | > > GINTSTS_OTGINT | GINTSTS_USBSUSP | > > - GINTSTS_WKUPINT, > > + GINTSTS_WKUPINT | > > + GINTSTS_INCOMPL_SOIN | GINTSTS_INCOMPL_SOOUT, > > hsotg->regs + GINTMSK); > > > > if (using_dma(hsotg)) > > @@ -2581,6 +2584,48 @@ irq_retry: > > s3c_hsotg_dump(hsotg); > > } > > > > + if (gintsts & GINTSTS_INCOMPL_SOIN) { > > + u32 idx; > > + struct s3c_hsotg_ep *hs_ep; > > + > > + dev_dbg(hsotg->dev, "%s: GINTSTS_INCOMPL_SOIN\n", > __func__); > > + for (idx = 1; idx < MAX_EPS_CHANNELS; idx++) { > > + hs_ep = hsotg->eps_in[idx]; > > + if (hs_ep->isochronous && !hs_ep->parity_set) { > > + u32 epctl_reg = DIEPCTL(idx); > > + u32 ctrl = readl(hsotg->regs + epctl_reg); > > + > > + if (ctrl & DXEPCTL_EOFRNUM) > > + ctrl |= DXEPCTL_SETEVENFR; > > + else > > + ctrl |= DXEPCTL_SETODDFR; > > + writel(ctrl, hsotg->regs + epctl_reg); > > + } > > + } > > + writel(GINTSTS_INCOMPL_SOIN, hsotg->regs + GINTSTS); > > + } > > + > > + if (gintsts & GINTSTS_INCOMPL_SOOUT) { > > + u32 idx; > > + struct s3c_hsotg_ep *hs_ep; > > + > > + dev_dbg(hsotg->dev, "%s: GINTSTS_INCOMPL_SOOUT\n", > __func__); > > + for (idx = 1; idx < MAX_EPS_CHANNELS; idx++) { > > + hs_ep = hsotg->eps_out[idx]; > > + if (hs_ep->isochronous && !hs_ep->parity_set) { > > + u32 epctl_reg = DOEPCTL(idx); > > + u32 ctrl = readl(hsotg->regs + epctl_reg); > > + > > + if (ctrl & DXEPCTL_EOFRNUM) > > + ctrl |= DXEPCTL_SETEVENFR; > > + else > > + ctrl |= DXEPCTL_SETODDFR; > > + writel(ctrl, hsotg->regs + epctl_reg); > > + } > > + } > > + writel(GINTSTS_INCOMPL_SOOUT, hsotg->regs + GINTSTS); > > + } > > + > > /* > > * if we've had fifo events, we should try and go around the > > * loop again to see if there's any point in returning yet. > > @@ -2667,6 +2712,7 @@ static int s3c_hsotg_ep_enable(struct usb_ep > *ep, > > hs_ep->periodic = 0; > > hs_ep->halted = 0; > > hs_ep->interval = desc->bInterval; > > + hs_ep->parity_set = 0; > > > I'm not quite sure what the parity_set flag does in this patch. > Shouldn't you be able to just toggle the even/odd frame when you get the > interrupt? > > John > When Transfer Complete interrupt is received, we have the correct parity. Therefore we set the flag and we stop toggling. The parity_set flag indicates whether we have the correct parity set. Regards, Roman -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
