5.15-stable review patch. If anyone has any objections, please let me know.
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From: Michael Grzeschik m.grzeschik@pengutronix.de
[ Upstream commit af076a41f8a28faf9ceb9dd2d88aef2c202ef39a ]
It is possible that the gadget will be disabled, while the udc is suspended. When enabling the udc in that case, the clock gating will not be enabled again. Leaving the phy unclocked. Even when the udc is not enabled, connecting this powered but not clocked phy leads to enumeration errors on the host side.
To ensure that the clock gating will be in an valid state, we ensure that the clock gating will be enabled before stopping the udc.
Signed-off-by: Michael Grzeschik m.grzeschik@pengutronix.de Acked-by: Minas Harutyunyan hminas@synopsys.com Link: https://lore.kernel.org/r/20250417-dwc2_clock_gating-v1-1-8ea7c4d53d73@pengu... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/dwc2/gadget.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c index 7d8523398e191..525d1d0cfc249 100644 --- a/drivers/usb/dwc2/gadget.c +++ b/drivers/usb/dwc2/gadget.c @@ -4602,6 +4602,12 @@ static int dwc2_hsotg_udc_stop(struct usb_gadget *gadget) if (!hsotg) return -ENODEV;
+ /* Exit clock gating when driver is stopped. */ + if (hsotg->params.power_down == DWC2_POWER_DOWN_PARAM_NONE && + hsotg->bus_suspended && !hsotg->params.no_clock_gating) { + dwc2_gadget_exit_clock_gating(hsotg, 0); + } + /* all endpoints should be shutdown */ for (ep = 1; ep < hsotg->num_of_eps; ep++) { if (hsotg->eps_in[ep])