usb: dwc2: also exit clock_gating when stopping udc while suspended
authorMichael Grzeschik <m.grzeschik@pengutronix.de>
Thu, 17 Apr 2025 17:40:17 +0000 (19:40 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 25 Apr 2025 11:21:09 +0000 (13:21 +0200)
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@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/dwc2/gadget.c

index 300ea4969f0cff9cae4d096f0c188405c122f4db..f323fb5597b32fba85ea0e5dbb561a53cbc27e9b 100644 (file)
@@ -4604,6 +4604,12 @@ 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])