| Message ID | 20190412224149.106971-3-dianders@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | usb: dwc2: Another attempt handling rk3288's remote wake quirk | expand |
On Fri, Apr 12, 2019 at 03:41:47PM -0700, Douglas Anderson 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), 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: Douglas Anderson <dianders@chromium.org> > Signed-off-by: Yunzhi Li <lyz@rock-chips.com> > --- > > drivers/usb/dwc2/core.h | 5 +++++ > drivers/usb/dwc2/core_intr.c | 12 ++++++++++++ > drivers/usb/dwc2/hcd.c | 16 +++++++++++++--- > drivers/usb/dwc2/platform.c | 9 +++++++++ > 4 files changed, 39 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h > index 30bab8463c96..f30748f4fe7e 100644 > --- a/drivers/usb/dwc2/core.h > +++ b/drivers/usb/dwc2/core.h > @@ -859,6 +859,8 @@ struct dwc2_hregs_backup { > * @gadget_enabled: Peripheral mode sub-driver initialization indicator. > * @ll_hw_enabled: Status of low-level hardware resources. > * @hibernated: True if core is hibernated > + * @reset_phy_on_wake: Quirk saying that we should assert PHY reset on a > + * remote wakeup. > * @frame_number: Frame number read from the core. For both device > * and host modes. The value ranges are from 0 > * to HFNUM_MAX_FRNUM. > @@ -972,6 +974,7 @@ struct dwc2_hregs_backup { > * @status_buf_dma: DMA address for status_buf > * @start_work: Delayed work for handling host A-cable connection > * @reset_work: Delayed work for handling a port reset > + * @phy_reset_work: Work structure for doing a PHY reset > * @otg_port: OTG port number > * @frame_list: Frame list > * @frame_list_dma: Frame list DMA address > @@ -1045,6 +1048,7 @@ struct dwc2_hsotg { > unsigned int gadget_enabled:1; > unsigned int ll_hw_enabled:1; > unsigned int hibernated:1; > + unsigned int reset_phy_on_wake:1; > u16 frame_number; > > struct phy *phy; > @@ -1147,6 +1151,7 @@ struct dwc2_hsotg { > > struct delayed_work start_work; > struct delayed_work reset_work; > + struct work_struct phy_reset_work; > u8 otg_port; > u32 *frame_list; > dma_addr_t frame_list_dma; > diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c > index 19ae2595f1c3..16ff33574116 100644 > --- a/drivers/usb/dwc2/core_intr.c > +++ b/drivers/usb/dwc2/core_intr.c > @@ -435,6 +435,18 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) > /* Restart the Phy Clock */ > pcgcctl &= ~PCGCTL_STOPPCLK; > dwc2_writel(hsotg, pcgcctl, PCGCTL); > + > + /* > + * If we've got this quirk then the PHY is stuck upon > + * wakeup. Assert reset. This will propagate out and > + * eventually we'll re-enumerate the device. Not great > + * but the best we can do. We can't call phy_reset() > + * at interrupt time but there's no hurry, so we'll > + * schedule it for later. > + */ > + if (hsotg->reset_phy_on_wake) > + schedule_work(&hsotg->phy_reset_work); > + > mod_timer(&hsotg->wkp_timer, > jiffies + msecs_to_jiffies(71)); > } else { > diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c > index 3f087962f498..332349148d3f 100644 > --- a/drivers/usb/dwc2/hcd.c > +++ b/drivers/usb/dwc2/hcd.c > @@ -4376,6 +4376,17 @@ static void dwc2_hcd_reset_func(struct work_struct *work) > spin_unlock_irqrestore(&hsotg->lock, flags); > } > > +static void dwc2_hcd_phy_reset_func(struct work_struct *work) > +{ > + struct dwc2_hsotg *hsotg = container_of(work, struct dwc2_hsotg, > + phy_reset_work); > + int ret; > + > + ret = phy_reset(hsotg->phy); > + if (ret) > + dev_warn(hsotg->dev, "PHY reset failed\n"); > +} > + > /* > * ========================================================================= > * Linux HC Driver Functions > @@ -5271,11 +5282,10 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg) > hsotg->hc_ptr_array[i] = channel; > } > > - /* Initialize hsotg start work */ > + /* Initialize work */ > INIT_DELAYED_WORK(&hsotg->start_work, dwc2_hcd_start_func); > - > - /* Initialize port reset work */ > INIT_DELAYED_WORK(&hsotg->reset_work, dwc2_hcd_reset_func); > + INIT_WORK(&hsotg->phy_reset_work, dwc2_hcd_phy_reset_func); You also want to make sure that the work is cancelled when the controller is stopped/removed. It seems dwc2_hcd_stop() would be a suitable place for that.
Hi, On Fri, Apr 12, 2019 at 4:56 PM Matthias Kaehlcke <mka@chromium.org> wrote: > > @@ -5271,11 +5282,10 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg) > > hsotg->hc_ptr_array[i] = channel; > > } > > > > - /* Initialize hsotg start work */ > > + /* Initialize work */ > > INIT_DELAYED_WORK(&hsotg->start_work, dwc2_hcd_start_func); > > - > > - /* Initialize port reset work */ > > INIT_DELAYED_WORK(&hsotg->reset_work, dwc2_hcd_reset_func); > > + INIT_WORK(&hsotg->phy_reset_work, dwc2_hcd_phy_reset_func); > > You also want to make sure that the work is cancelled when the > controller is stopped/removed. It seems dwc2_hcd_stop() would be a > suitable place for that. Good point. dwc2_hcd_stop() doesn't work though because it's called with interrupts disabled (because it's holding the hsotg->lock spinlock). I put it in dwc2_hcd_free() where there's another similar cancel. -Doug
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index 30bab8463c96..f30748f4fe7e 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -859,6 +859,8 @@ struct dwc2_hregs_backup { * @gadget_enabled: Peripheral mode sub-driver initialization indicator. * @ll_hw_enabled: Status of low-level hardware resources. * @hibernated: True if core is hibernated + * @reset_phy_on_wake: Quirk saying that we should assert PHY reset on a + * remote wakeup. * @frame_number: Frame number read from the core. For both device * and host modes. The value ranges are from 0 * to HFNUM_MAX_FRNUM. @@ -972,6 +974,7 @@ struct dwc2_hregs_backup { * @status_buf_dma: DMA address for status_buf * @start_work: Delayed work for handling host A-cable connection * @reset_work: Delayed work for handling a port reset + * @phy_reset_work: Work structure for doing a PHY reset * @otg_port: OTG port number * @frame_list: Frame list * @frame_list_dma: Frame list DMA address @@ -1045,6 +1048,7 @@ struct dwc2_hsotg { unsigned int gadget_enabled:1; unsigned int ll_hw_enabled:1; unsigned int hibernated:1; + unsigned int reset_phy_on_wake:1; u16 frame_number; struct phy *phy; @@ -1147,6 +1151,7 @@ struct dwc2_hsotg { struct delayed_work start_work; struct delayed_work reset_work; + struct work_struct phy_reset_work; u8 otg_port; u32 *frame_list; dma_addr_t frame_list_dma; diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c index 19ae2595f1c3..16ff33574116 100644 --- a/drivers/usb/dwc2/core_intr.c +++ b/drivers/usb/dwc2/core_intr.c @@ -435,6 +435,18 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) /* Restart the Phy Clock */ pcgcctl &= ~PCGCTL_STOPPCLK; dwc2_writel(hsotg, pcgcctl, PCGCTL); + + /* + * If we've got this quirk then the PHY is stuck upon + * wakeup. Assert reset. This will propagate out and + * eventually we'll re-enumerate the device. Not great + * but the best we can do. We can't call phy_reset() + * at interrupt time but there's no hurry, so we'll + * schedule it for later. + */ + if (hsotg->reset_phy_on_wake) + schedule_work(&hsotg->phy_reset_work); + mod_timer(&hsotg->wkp_timer, jiffies + msecs_to_jiffies(71)); } else { diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 3f087962f498..332349148d3f 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -4376,6 +4376,17 @@ static void dwc2_hcd_reset_func(struct work_struct *work) spin_unlock_irqrestore(&hsotg->lock, flags); } +static void dwc2_hcd_phy_reset_func(struct work_struct *work) +{ + struct dwc2_hsotg *hsotg = container_of(work, struct dwc2_hsotg, + phy_reset_work); + int ret; + + ret = phy_reset(hsotg->phy); + if (ret) + dev_warn(hsotg->dev, "PHY reset failed\n"); +} + /* * ========================================================================= * Linux HC Driver Functions @@ -5271,11 +5282,10 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg) hsotg->hc_ptr_array[i] = channel; } - /* Initialize hsotg start work */ + /* Initialize work */ INIT_DELAYED_WORK(&hsotg->start_work, dwc2_hcd_start_func); - - /* Initialize port reset work */ INIT_DELAYED_WORK(&hsotg->reset_work, dwc2_hcd_reset_func); + INIT_WORK(&hsotg->phy_reset_work, dwc2_hcd_phy_reset_func); /* * Allocate space for storing data on status transactions. Normally no diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c index c0b64d483552..9b65b766e0b9 100644 --- a/drivers/usb/dwc2/platform.c +++ b/drivers/usb/dwc2/platform.c @@ -481,6 +481,15 @@ static int dwc2_driver_probe(struct platform_device *dev) hsotg->gadget_enabled = 1; } + hsotg->reset_phy_on_wake = + of_property_read_bool(dev->dev.of_node, + "snps,reset-phy-on-wake"); + if (hsotg->reset_phy_on_wake && !hsotg->phy) { + dev_warn(hsotg->dev, + "Quirk reset-phy-on-wake only supports generic PHYs\n"); + hsotg->reset_phy_on_wake = false; + } + if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) { retval = dwc2_hcd_init(hsotg); if (retval) {