On 9/9/2015 11:16 AM, Roman Bacik wrote: >> -----Original Message----- >> From: John Youn [mailto:John.Youn@xxxxxxxxxxxx] >> Sent: September-03-15 11:53 PM >> To: Scott Branden; John Youn; Greg Kroah-Hartman; linux- >> usb@xxxxxxxxxxxxxxx; Roman Bacik >> Cc: linux-kernel@xxxxxxxxxxxxxxx; bcm-kernel-feedback-list >> Subject: Re: [PATCH v2 1/1] usb: dwc2: gadget: parity fix in isochronous mode >> >> On 8/31/2015 9:17 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> >>> Signed-off-by: Scott Branden <sbranden@xxxxxxxxxxxx> >>> --- >>> drivers/usb/dwc2/core.h | 1 + >>> drivers/usb/dwc2/gadget.c | 51 >> ++++++++++++++++++++++++++++++++++++++++++++++- >>> drivers/usb/dwc2/hw.h | 1 + >>> 3 files changed, 52 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index >>> 0ed87620..a5634fd 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 has_correct_parity:1; >>> >>> char name[10]; >>> }; >>> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c >>> index 4d47b7c..fac3e2f 100644 >>> --- a/drivers/usb/dwc2/gadget.c >>> +++ b/drivers/usb/dwc2/gadget.c >>> @@ -1954,6 +1954,7 @@ static void s3c_hsotg_epint(struct dwc2_hsotg >> *hsotg, unsigned int idx, >>> ints &= ~DXEPINT_XFERCOMPL; >>> >>> if (ints & DXEPINT_XFERCOMPL) { >>> + hs_ep->has_correct_parity = 1; >>> if (hs_ep->isochronous && hs_ep->interval == 1) { >>> if (ctrl & DXEPCTL_EOFRNUM) >>> ctrl |= DXEPCTL_SETEVENFR; >>> @@ -2316,7 +2317,8 @@ 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 +2583,52 @@ irq_retry: >>> s3c_hsotg_dump(hsotg); >>> } >>> >>> + if (gintsts & GINTSTS_INCOMPL_SOIN) { >>> + u32 idx, epctl_reg, ctrl; >>> + struct s3c_hsotg_ep *hs_ep; >>> + >>> + dev_dbg(hsotg->dev, "%s: GINTSTS_INCOMPL_SOIN\n", >> __func__); >>> + for (idx = 1; idx < MAX_EPS_CHANNELS; idx++) { >> >> Valid endpoints are only up to hsotg->num_of_eps so this might crash on >> certain configurations. >> >> Also, have you tried to find the endpoint which caused the incomplete >> interrupt by reading the control registers as described in the databook? >> > > We are using procedure based on description from this source: > > Synopsys, Inc. SolvNet 527 > DesignWare.com > 3.00a > April 2012 > USB 2.0 Hi-Speed On-The-Go (OTG) Databook Isochronous Endpoints in DWC_otg Slave Mode > > Synopsys databook is not in a public domain to quote the exact paragraph here. You can find it in Chapter E, pp 526-527. There is no register in this databook, which would provide information about the source endpoint of the incomplete interrupt, as you have described. > > Please, provide an exact reference and possibly enough information that we can turn it into a working code. > You can check the source of the interrupt by reading the DSTS and ep control registers as described in the databook page 526, last bullet, and 527 first bullet. John -- 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
