[PATCH 5.3 098/135] usb: dwc2: use a longer core rest timeout in dwc2_core_reset()

Greg Kroah-Hartman
2019-12-03T22:43:25Z

From: Mathias Kresin <dev@kresin.me>

commit 6689f0f4bb14e50917ba42eb9b41c25e0184970c upstream.

Testing on different generations of Lantiq MIPS SoC based boards, showed
that it takes up to 1500 us until the core reset bit is cleared.

The driver from the vendor SDK (ifxhcd) uses a 1 second timeout. Use the
same timeout to fix wrong hang detections and make the driver work for
Lantiq MIPS SoCs.

At least till kernel 4.14 the hanging reset only caused a warning but
the driver was probed successful. With kernel 4.19 errors out with
EBUSY.

Cc: linux-stable <stable@vger.kernel.org> # 4.19+
Signed-off-by: Mathias Kresin <dev@kresin.me>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/dwc2/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/dwc2/core.c
+++ b/drivers/usb/dwc2/core.c
@@ -524,7 +524,7 @@ int dwc2_core_reset(struct dwc2_hsotg *h
greset |= GRSTCTL_CSFTRST;
dwc2_writel(hsotg, greset, GRSTCTL);

- if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_CSFTRST, 50)) {
+ if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_CSFTRST, 10000)) {
dev_warn(hsotg->dev, "%s: HANG! Soft Reset timeout GRSTCTL GRSTCTL_CSFTRST\n",
__func__);
return -EBUSY;