On Mon, 2014-02-03 at 21:13 +0000, Paul Zimmerman wrote: > > From: dinguyen@xxxxxxxxxx [mailto:dinguyen@xxxxxxxxxx] > > Sent: Monday, February 03, 2014 9:00 AM > > Hi Dinh, > > > According to the spec for the DWC2 controller, when the PRTINT interrupt fires, > > the application must clear the appropriate status bit in the Host Port Control > > and Status register to clear this bit. > > > > When disconnecting an A-cable when the dwc2 host driver, the PRTINT fires, but > > only the GINTSTS_PRTINT status is cleared, no action is done with the HPRT0 > > register. The HPRT0_ENACHG bit in the HPRT0 must also be poked to correctly > > clear the GINTSTS_PRTINT interrupt. > > > > I am seeing this behavoir on v2.93 of the DWC2 IP. When I disconnect an OTG > > A-cable adapter, the PRTINT interrupt fires when the DWC2 is in device mode > > and is never cleared. > > > > This patch adds the function to read the HPRT0 register when the PRTINT fires > > and the dwc2 IP has already transitioned to device mode. This function is only > > clearing the HPRT0_ENACHG bit for now, but can be modified to handle more. > > > > Signed-off-by: Dinh Nguyen <dinguyen@xxxxxxxxxx> > > Cc: Paul Zimmerman <paulz@xxxxxxxxxxxx> > > Cc: Matt Porter <mporter@xxxxxxxxxx> > > Cc: Matthijs Kooijman <matthijs@xxxxxxxx> > > --- > > drivers/usb/dwc2/core_intr.c | 20 ++++++++++++++++++++ > > 1 file changed, 20 insertions(+) > > > > diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c > > index 12dde73..64fee902 100644 > > --- a/drivers/usb/dwc2/core_intr.c > > +++ b/drivers/usb/dwc2/core_intr.c > > @@ -76,6 +76,24 @@ static const char *dwc2_op_state_str(struct dwc2_hsotg *hsotg) > > } > > > > /** > > + * dwc2_handle_usb_port_intr - handles OTG PRTINT interrupts. > > + * When the PRTINT interrupt fires, there are certain status bits in the Host > > + * Port that needs to get cleared. > > + * > > + * @hsotg: Programming view of DWC_otg controller > > + */ > > +static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg) > > +{ > > + u32 hprt0; > > + > > + hprt0 = readl(hsotg->regs + HPRT0); > > + if (hprt0 & HPRT0_ENACHG) { > > This would be a little cleaner like this: > > u32 hprt0 = readl(hsotg->regs + HPRT0); > > if (hprt0 & HPRT0_ENACHG) { > Ok... > > + hprt0 |= HPRT0_ENACHG; > > + writel(hprt0, hsotg->regs + HPRT0); > > + } > > +} > > + > > +/** > > * dwc2_handle_mode_mismatch_intr() - Logs a mode mismatch warning message > > * > > * @hsotg: Programming view of DWC_otg controller > > @@ -583,8 +601,10 @@ irq_retry: > > if (dwc2_is_device_mode(hsotg)) { > > dev_dbg(hsotg->dev, > > " --Port interrupt received in Device mode--\n"); > > + dwc2_handle_usb_port_intr(hsotg); > > gintsts = GINTSTS_PRTINT; > > writel(gintsts, hsotg->regs + GINTSTS); > > + dwc2_handle_usb_port_intr(hsotg); > > Why do you have two calls to dwc2_handle_usb_port_intr() here? Does it > still work if you remove the first call? > > I don't see this problem on our internal FPGA platform, so I will just > have to take your word that this fixes a problem. If you resubmit the > patch with just a single call to dwc2_handle_usb_port_intr(), I will > ack it. > Yes, sorry for that. It must have been a merge error on my part between my branches. Yes, a single call to dwc2_handle_usb_port_intr() is enough. will send out v2. Thanks, DInh -- 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
