6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jisheng Zhang jszhang@kernel.org
[ Upstream commit 2b94b054ac4974ad2f89f7f7461840c851933adb ]
dwc2 on most platforms needs phy controller, clock and power supply. All of them must be enabled/activated to properly operate. If dwc2 is configured as peripheral mode, then all the above three hardware resources are disabled at the end of the probe:
/* Gadget code manages lowlevel hw on its own */ if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) dwc2_lowlevel_hw_disable(hsotg);
But the dwc2_suspend() tries to read the dwc2's reg to check whether is_device_mode or not, this would result in hang during suspend if dwc2 is configured as peripheral mode.
Fix this hang by bypassing suspend/resume if lowlevel hw isn't enabled.
Fixes: 09a75e857790 ("usb: dwc2: refactor common low-level hw code to platform.c") Signed-off-by: Jisheng Zhang jszhang@kernel.org Link: https://patch.msgid.link/20251104002503.17158-3-jszhang@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/dwc2/platform.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c index fad6f68f86bd6..e80982c817d7d 100644 --- a/drivers/usb/dwc2/platform.c +++ b/drivers/usb/dwc2/platform.c @@ -649,9 +649,13 @@ static int dwc2_driver_probe(struct platform_device *dev) static int __maybe_unused dwc2_suspend(struct device *dev) { struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); - bool is_device_mode = dwc2_is_device_mode(dwc2); + bool is_device_mode; int ret = 0;
+ if (!dwc2->ll_hw_enabled) + return 0; + + is_device_mode = dwc2_is_device_mode(dwc2); if (is_device_mode) dwc2_hsotg_suspend(dwc2);
@@ -702,6 +706,9 @@ static int __maybe_unused dwc2_resume(struct device *dev) struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); int ret = 0;
+ if (!dwc2->ll_hw_enabled) + return 0; + if (dwc2->phy_off_for_suspend && dwc2->ll_hw_enabled) { ret = __dwc2_lowlevel_hw_enable(dwc2); if (ret)