[PATCH] usb: dwc3: qcom: Add shutdown handler

[Prashanth K <prashanth.k@oss.qualcomm.com>]

Currently during system reboot, SMMU disables its translations
while devices like USB may still be actively using DMA buffers.
This can lead to NOC errors and system crashes due to invalid
memory access.

Address this by adding a shutdown callback to dwc3-qcom, which
ensures proper teardown of UDC stack and prevents DWC3 controller
from accessing memory after SMMU translation is disabled. Reuse
the existing remove callback for this purpose.

Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
---
 drivers/usb/dwc3/dwc3-qcom.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index ca7e1c02773a..308360a32c93 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -764,11 +764,14 @@ static void dwc3_qcom_remove(struct platform_device *pdev)
 	struct dwc3 *dwc = platform_get_drvdata(pdev);
 	struct dwc3_qcom *qcom = to_dwc3_qcom(dwc);
 
-	dwc3_core_remove(&qcom->dwc);
+	if (pm_runtime_resume_and_get(qcom->dev) < 0)
+		return;
 
+	dwc3_core_remove(&qcom->dwc);
 	clk_bulk_disable_unprepare(qcom->num_clocks, qcom->clks);
-
 	dwc3_qcom_interconnect_exit(qcom);
+
+	pm_runtime_put_noidle(qcom->dev);
 }
 
 static int dwc3_qcom_pm_suspend(struct device *dev)
@@ -873,6 +876,7 @@ MODULE_DEVICE_TABLE(of, dwc3_qcom_of_match);
 static struct platform_driver dwc3_qcom_driver = {
 	.probe		= dwc3_qcom_probe,
 	.remove		= dwc3_qcom_remove,
+	.shutdown	= dwc3_qcom_remove,
 	.driver		= {
 		.name	= "dwc3-qcom",
 		.pm	= pm_ptr(&dwc3_qcom_dev_pm_ops),
-- 
2.25.1