Commit 6689f0f4 authored Jul 07, 2019 by Mathias Kresin Committed by Felipe Balbi Oct 22, 2019

usb: dwc2: use a longer core rest timeout in dwc2_core_reset()



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>

parent a9a367d0

drivers/usb/dwc2/core.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -524,7 +524,7 @@ int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait)
		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;

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