| Message ID | 20240913232145.3507723-1-royluo@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] usb: dwc3: re-enable runtime PM after failed resume | expand |
On Fri, Sep 13, 2024, Roy Luo wrote: > When dwc3_resume_common() returns an error, runtime pm is left in > suspended and disabled state in dwc3_resume(). Since the device > is suspended, its parent devices (like the power domain or glue > driver) could also be suspended and may have released resources > that dwc requires. Consequently, calling dwc3_suspend_common() in > this situation could result in attempts to access unclocked or > unpowered registers. > To prevent these problems, runtime PM should always be re-enabled, > even after failed resume attempts. This ensures that > dwc3_suspend_common() is skipped in such cases. > > Fixes: 68c26fe58182 ("usb: dwc3: set pm runtime active before resume common") > Cc: stable@vger.kernel.org > Signed-off-by: Roy Luo <royluo@google.com> > --- > drivers/usb/dwc3/core.c | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index ccc3895dbd7f..4bd73b5fe41b 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -2537,7 +2537,7 @@ static int dwc3_suspend(struct device *dev) > static int dwc3_resume(struct device *dev) > { > struct dwc3 *dwc = dev_get_drvdata(dev); > - int ret; > + int ret = 0; > > pinctrl_pm_select_default_state(dev); > > @@ -2545,14 +2545,12 @@ static int dwc3_resume(struct device *dev) > pm_runtime_set_active(dev); > > ret = dwc3_resume_common(dwc, PMSG_RESUME); > - if (ret) { > + if (ret) > pm_runtime_set_suspended(dev); > - return ret; > - } > > pm_runtime_enable(dev); > > - return 0; > + return ret; > } > > static void dwc3_complete(struct device *dev) > > base-commit: ad618736883b8970f66af799e34007475fe33a68 > -- > 2.46.0.662.g92d0881bb0-goog > Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> Thanks, Thinh
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index ccc3895dbd7f..4bd73b5fe41b 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -2537,7 +2537,7 @@ static int dwc3_suspend(struct device *dev) static int dwc3_resume(struct device *dev) { struct dwc3 *dwc = dev_get_drvdata(dev); - int ret; + int ret = 0; pinctrl_pm_select_default_state(dev); @@ -2545,14 +2545,12 @@ static int dwc3_resume(struct device *dev) pm_runtime_set_active(dev); ret = dwc3_resume_common(dwc, PMSG_RESUME); - if (ret) { + if (ret) pm_runtime_set_suspended(dev); - return ret; - } pm_runtime_enable(dev); - return 0; + return ret; } static void dwc3_complete(struct device *dev)
When dwc3_resume_common() returns an error, runtime pm is left in suspended and disabled state in dwc3_resume(). Since the device is suspended, its parent devices (like the power domain or glue driver) could also be suspended and may have released resources that dwc requires. Consequently, calling dwc3_suspend_common() in this situation could result in attempts to access unclocked or unpowered registers. To prevent these problems, runtime PM should always be re-enabled, even after failed resume attempts. This ensures that dwc3_suspend_common() is skipped in such cases. Fixes: 68c26fe58182 ("usb: dwc3: set pm runtime active before resume common") Cc: stable@vger.kernel.org Signed-off-by: Roy Luo <royluo@google.com> --- drivers/usb/dwc3/core.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) base-commit: ad618736883b8970f66af799e34007475fe33a68