usb: dwc2: Add exit clock gating before removing driver

When dwc2 core is in clock gating mode loading driver
again causes driver fail. Because in that mode
registers are not accessible.

Added a flow of exiting clock gating mode
to avoid the driver reload failure.

Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210413073731.3C81BA022E@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index b28b8cd45799b496d82596b5c4d8c7d84d6c856b..f8b819cfa80e694ee87df34b4c81fb1d58543e78 100644 (file)
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -326,6 +326,15 @@ static int dwc2_driver_remove(struct platform_device *dev)
                                "exit partial_power_down failed\n");
        }
 
+       /* Exit clock gating when driver is removed. */
+       if (hsotg->params.power_down == DWC2_POWER_DOWN_PARAM_NONE &&
+           hsotg->bus_suspended) {
+               if (dwc2_is_device_mode(hsotg))
+                       dwc2_gadget_exit_clock_gating(hsotg, 0);
+               else
+                       dwc2_host_exit_clock_gating(hsotg, 0);
+       }
+
        dwc2_debugfs_exit(hsotg);
        if (hsotg->hcd_enabled)
                dwc2_hcd_remove(hsotg);