[PATCH v2 12/12] usb: dwc2: Add exit clock gating before removing driver

From: Artur Petrosyan
Date: Tue Apr 13 2021 - 03:37:57 EST


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@xxxxxxxxxxxx>
---
Changes in v2:
- None

drivers/usb/dwc2/platform.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index b28b8cd45799..f8b819cfa80e 100644
--- 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);
--
2.25.1