Hi, John Youn <John.Youn@xxxxxxxxxxxx> writes: >> Baolin Wang <baolin.wang@xxxxxxxxxx> writes: >>>> Baolin Wang <baolin.wang@xxxxxxxxxx> writes: >>>>> When dwc3 controller acts as host role with attaching slow speed device >>>>> (like mouse or keypad). Then if we plugged out the slow speed device, >>>>> it will timeout to run the deconfiguration endpoint command to drop the >>>>> endpoint's resources. Some xHCI command timeout log as below when >>>>> disconnecting one slow device: >>>>> >>>>> [ 99.807739] c0 xhci-hcd.0.auto: Port Status Change Event for port 1 >>>>> [ 99.814699] c0 xhci-hcd.0.auto: resume root hub >>>>> [ 99.819992] c0 xhci-hcd.0.auto: handle_port_status: starting port >>>>> polling. >>>>> [ 99.827808] c0 xhci-hcd.0.auto: get port status, actual port 0 status >>>>> = 0x202a0 >>>>> [ 99.835903] c0 xhci-hcd.0.auto: Get port status returned 0x10100 >>>>> [ 99.850052] c0 xhci-hcd.0.auto: clear port connect change, actual >>>>> port 0 status = 0x2a0 >>>>> [ 99.859313] c0 xhci-hcd.0.auto: Cancel URB ffffffc01ed6cd00, dev 1, >>>>> ep 0x81, starting at offset 0xc406d210 >>>>> [ 99.869645] c0 xhci-hcd.0.auto: // Ding dong! >>>>> [ 99.874776] c0 xhci-hcd.0.auto: Stopped on Transfer TRB >>>>> [ 99.880713] c0 xhci-hcd.0.auto: Removing canceled TD starting at >>>>> 0xc406d210 (dma). >>>>> [ 99.889012] c0 xhci-hcd.0.auto: Finding endpoint context >>>>> [ 99.895069] c0 xhci-hcd.0.auto: Cycle state = 0x1 >>>>> [ 99.900519] c0 xhci-hcd.0.auto: New dequeue segment = >>>>> ffffffc1112f0880 (virtual) >>>>> [ 99.908655] c0 xhci-hcd.0.auto: New dequeue pointer = 0xc406d220 (DMA) >>>>> [ 99.915927] c0 xhci-hcd.0.auto: Set TR Deq Ptr cmd, new deq seg = >>>>> ffffffc1112f0880 (0xc406d000 dma), >>>>> new deq ptr = ffffff8002175220 >>>>> (0xc406d220 dma), new cycle = 1 >>>>> [ 99.931242] c0 xhci-hcd.0.auto: // Ding dong! >>>>> [ 99.936360] c0 xhci-hcd.0.auto: Successful Set TR Deq Ptr cmd, >>>>> deq = @c406d220 >>>>> [ 99.944458] c0 xhci-hcd.0.auto: xhci_hub_status_data: stopping port >>>>> polling. >>>>> [ 100.047619] c0 xhci-hcd.0.auto: xhci_drop_endpoint called for udev >>>>> ffffffc01ae08800 >>>>> [ 100.057002] c0 xhci-hcd.0.auto: drop ep 0x81, slot id 1, new drop >>>>> flags = 0x8, new add flags = 0x0 >>>>> [ 100.067878] c0 xhci-hcd.0.auto: xhci_check_bandwidth called for udev >>>>> ffffffc01ae08800 >>>>> [ 100.076868] c0 xhci-hcd.0.auto: New Input Control Context: >>>>> >>>>> ...... >>>>> >>>>> [ 100.427252] c0 xhci-hcd.0.auto: // Ding dong! >>>>> [ 105.430728] c0 xhci-hcd.0.auto: Command timeout >>>>> [ 105.436029] c0 xhci-hcd.0.auto: Abort command ring >>>>> [ 113.558223] c0 xhci-hcd.0.auto: Command completion event does not match >>>>> command >>>>> [ 113.569778] c0 xhci-hcd.0.auto: Timeout while waiting for configure >>>>> endpoint command >>>>> >>>>> The reason is it will suspend USB phy to disable phy clock when >>>>> disconnecting the slow USB decice, that will hang on the xHCI commands >>>>> executing which depends on the phy clock. >>>>> >>>>> Thus we should disable USB2.0 phy suspend feature when dwc3 acts as host >>>>> role. >>>>> >>>>> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx> >>>>> --- >>>>> drivers/usb/dwc3/core.c | 14 ++++++++++++++ >>>>> 1 file changed, 14 insertions(+) >>>>> >>>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c >>>>> index 9a4a5e4..0b646cf 100644 >>>>> --- a/drivers/usb/dwc3/core.c >>>>> +++ b/drivers/usb/dwc3/core.c >>>>> @@ -565,6 +565,20 @@ static int dwc3_phy_setup(struct dwc3 *dwc) >>>>> if (dwc->revision > DWC3_REVISION_194A) >>>>> reg |= DWC3_GUSB2PHYCFG_SUSPHY; >>>>> >>>>> + /* >>>>> + * When dwc3 controller acts as host role with attaching one slow speed >>>>> + * device (like mouse or keypad). Then if we plugged out the slow speed >>>>> + * device, it will timeout to run the deconfiguration endpoint command. >>>>> + * The reason is it will suspend USB phy to disable phy clock when >>>>> + * disconnecting slow speed decice, which will affect the xHCI commands >>>>> + * executing. >>>>> + * >>>>> + * Thus we should disable USB 2.0 phy suspend feature when dwc3 acts as >>>>> + * host role. >>>>> + */ >>>>> + if (dwc->dr_mode == USB_DR_MODE_HOST || dwc->dr_mode == USB_DR_MODE_OTG) >>>>> + reg &= ~DWC3_GUSB2PHYCFG_SUSPHY; >>>> >>>> which version of the core you're using? Recent version (since 1.94A, >>> >>> My version is 2.80a. >>> >>>> IIRC) can manage core suspend automatically. Also, this patch of yours >>>> will cause a power consumption regression. >>> >>> Yes, it can manage core suspend automatically, that is the problem. >>> When plugging out one mouse or keypad device, the phy will suspend >>> automatically to disable the phy clock. But now the disconnecting >>> process is not finished, and some xHCI commands (like deconfiguration >>> endpoint command to drop endpoint resources) need depend on the phy >>> clock, which will hang on the system to timeout the command or abort >>> command ring to halt the xHCI. >>> >>> I agree with you it will cause a power consumption regression, but it >>> will cause serious problem if not. Do you have some suggestion? >> >> sorry for the long delay. This was lost in my inbox. >> >> I'm not sure this patch is the best solution. There's no mention in >> Databook that we should avoid PHY suspend when acting as host. Adding >> John here to see if John has any idea of how to fix this. >> > > I'm not familiar enough with XHCI side of things to say. > > I'll ask around to see if anyone has an idea. Thank you -- balbi
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