| Message ID | 20230627162018.739-1-jszhang@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e835c0a4e23c38531dcee5ef77e8d1cf462658c7 |
| Headers | show |
| Series | usb: dwc3: don't reset device side if dwc3 was configured as host-only | expand |
On Wed, Jun 28, 2023, Jisheng Zhang wrote: > Commit c4a5153e87fd ("usb: dwc3: core: Power-off core/PHYs on > system_suspend in host mode") replaces check for HOST only dr_mode with > current_dr_role. But during booting, the current_dr_role isn't > initialized, thus the device side reset is always issued even if dwc3 > was configured as host-only. What's more, on some platforms with host > only dwc3, aways issuing device side reset by accessing device register > block can cause kernel panic. > Ah... good catch! This should be backported to stable. So perhaps you or Greg can add Cc: stable@vger.kernel.org > Fixes: c4a5153e87fd ("usb: dwc3: core: Power-off core/PHYs on system_suspend in host mode") > Signed-off-by: Jisheng Zhang <jszhang@kernel.org> > --- > drivers/usb/dwc3/core.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index 7b2ce013cc5b..16d7a1d1cbfa 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -277,9 +277,9 @@ int dwc3_core_soft_reset(struct dwc3 *dwc) > /* > * We're resetting only the device side because, if we're in host mode, > * XHCI driver will reset the host block. If dwc3 was configured for > - * host-only mode, then we can return early. > + * host-only mode or current role is host, then we can return early. > */ > - if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) > + if (dwc->dr_mode == USB_DR_MODE_HOST || dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) > return 0; > > reg = dwc3_readl(dwc->regs, DWC3_DCTL); > -- > 2.40.1 > Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> Thanks, Thinh
It seems that this patch causes driver failed to initialize on rockchip rk3399 devices when DWC3 controller is configured as dual role. [ 2.827119] dwc3 fe900000.usb: error -ETIMEDOUT: failed to initialize core [ 2.827881] dwc3: probe of fe900000.usb failed with error -110 After some tests I am preliminarily certain that this patch caused the failure.
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 7b2ce013cc5b..16d7a1d1cbfa 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -277,9 +277,9 @@ int dwc3_core_soft_reset(struct dwc3 *dwc) /* * We're resetting only the device side because, if we're in host mode, * XHCI driver will reset the host block. If dwc3 was configured for - * host-only mode, then we can return early. + * host-only mode or current role is host, then we can return early. */ - if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) + if (dwc->dr_mode == USB_DR_MODE_HOST || dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) return 0; reg = dwc3_readl(dwc->regs, DWC3_DCTL);
Commit c4a5153e87fd ("usb: dwc3: core: Power-off core/PHYs on system_suspend in host mode") replaces check for HOST only dr_mode with current_dr_role. But during booting, the current_dr_role isn't initialized, thus the device side reset is always issued even if dwc3 was configured as host-only. What's more, on some platforms with host only dwc3, aways issuing device side reset by accessing device register block can cause kernel panic. Fixes: c4a5153e87fd ("usb: dwc3: core: Power-off core/PHYs on system_suspend in host mode") Signed-off-by: Jisheng Zhang <jszhang@kernel.org> --- drivers/usb/dwc3/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)