[PATCH v2] usb: dwc3: re-enable runtime PM after failed resume

[Roy Luo <royluo@google.com>]

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