From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Youn Subject: Re: [PATCH v8 2/3] usb: dwc2: assert phy reset when waking up in rk3288 platform Date: Wed, 19 Oct 2016 15:58:27 -0700 Message-ID: References: <1474743019-1050-1-git-send-email-ayaka@soulik.info> <1474743019-1050-3-git-send-email-ayaka@soulik.info> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: =?UTF-8?B?6ZmI6LGq?= , Randy Li Cc: "linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "John.Youn-HKixBCOQz3hWk0Htik3J/w@public.gmane.org" , "kishon-l0cyMroinI0@public.gmane.org" , "felipe.balbi-VuQAYsv1563Yd54FQh9/CA@public.gmane.org" , "mark.rutland-5wv7dgnIgG8@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Heiko Stuebner , "gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "randy.li-TNX95d0MmH7DzftRWevZcw@public.gmane.org" List-Id: linux-rockchip.vger.kernel.org On 10/15/2016 8:07 AM, 陈豪 wrote: > 2016-09-25 2:50 GMT+08:00 Randy Li : >> 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 >> --- >> drivers/usb/dwc2/core_intr.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c >> index d85c5c9..af27edc 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 +380,16 @@ 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")) >> + phy_reset(hsotg->phy); > > It will call mutex_lock in phy_reset. > > >> + >> mod_timer(&hsotg->wkp_timer, >> jiffies + msecs_to_jiffies(71)); >> } else { >> -- >> 2.7.4 >> > > What is the status of this patch？ > Sleeping calls(phy_reset ==> mutex) shouldn't be used in irq handler. > Randy will correct that？ > Yes, that's right, I missed that. It will have to be fixed. Regards, John -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html