On 9/5/2016 10:15 PM, Kishon Vijay Abraham I wrote: > Hi, > > On Sunday 04 September 2016 03:25 AM, Randy Li wrote: >> On the rk3288 USB host-only port (the one that's not the OTG-enabled >> port) the PHY can get into a bad state when a wakeup is asserted (not >> just a wakeup from full system suspend but also a wakeup from >> autosuspend). >> >> We can get the PHY out of its bad state by asserting its "port reset", >> but unfortunately that seems to assert a reset onto the USB bus so it >> could confuse things if we don't actually deenumerate / reenumerate the >> device. >> >> We can also get the PHY out of its bad state by fully resetting it using >> the reset from the CRU (clock reset unit) in chip, which does a more full >> reset. The CRU-based reset appears to actually cause devices on the bus >> to be removed and reinserted, which fixes the problem (albeit in a hacky >> way). >> >> It's unfortunate that we need to do a full re-enumeration of devices at >> wakeup time, but this is better than alternative of letting the bus get >> wedged. >> >> Signed-off-by: Randy Li <ayaka@xxxxxxxxxxx> >> --- >> drivers/usb/dwc2/core_intr.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c >> index d85c5c9..08485b7 100644 >> --- a/drivers/usb/dwc2/core_intr.c >> +++ b/drivers/usb/dwc2/core_intr.c >> @@ -345,6 +345,7 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg) >> static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) >> { >> int ret; >> + struct device_node *np = hsotg->dev->of_node; >> >> /* Clear interrupt */ >> dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); >> @@ -379,6 +380,17 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) >> /* Restart the Phy Clock */ >> pcgcctl &= ~PCGCTL_STOPPCLK; >> dwc2_writel(pcgcctl, hsotg->regs + PCGCTL); >> + >> + /* >> + * It is a quirk in Rockchip RK3288, causing by >> + * a hardware bug. This will propagate out and >> + * eventually we'll re-enumerate the device. >> + * Not great but the best we can do >> + */ >> + if (of_device_is_compatible(np, "rockchip,rk3288-usb") >> + && (NULL != hsotg->phy->ops->reset)) >> + hsotg->phy->ops->reset(hsotg->phy); > > never call the phy ops directly from the controller driver. It has to be > protected as well. It looks like we should be calling an API function instead, correct? Similar to the wrappers for the other ops. Regards, 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