[PATCH] usb: gadget: tegra-xudc: Fix idle suspend/resume

From: Thierry Reding
Date: Fri Apr 17 2020 - 13:05:51 EST


From: Thierry Reding <treding@xxxxxxxxxx>

When the XUDC device is idle (i.e. powergated), care must be taken not
to access any registers because that would lead to a crash.

Move the call to tegra_xudc_device_mode_off() into the same conditional
as the tegra_xudc_powergate() call to make sure we only force device
mode off if the XUDC is actually powered up.

Fixes: 49db427232fe ("usb: gadget: Add UDC driver for tegra XUSB device mode controller")
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
drivers/usb/gadget/udc/tegra-xudc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/tegra-xudc.c
index 52a6add961f4..dfabc54cdc27 100644
--- a/drivers/usb/gadget/udc/tegra-xudc.c
+++ b/drivers/usb/gadget/udc/tegra-xudc.c
@@ -3840,11 +3840,11 @@ static int __maybe_unused tegra_xudc_suspend(struct device *dev)

flush_work(&xudc->usb_role_sw_work);

- /* Forcibly disconnect before powergating. */
- tegra_xudc_device_mode_off(xudc);
-
- if (!pm_runtime_status_suspended(dev))
+ if (!pm_runtime_status_suspended(dev)) {
+ /* Forcibly disconnect before powergating. */
+ tegra_xudc_device_mode_off(xudc);
tegra_xudc_powergate(xudc);
+ }

pm_runtime_disable(dev);

--
2.24.1