>From DWC_usb31 databook section 1.3.2, once DWC3_DCTL_CSFTRST bit is
cleared, we must wait at least 50ms before accessing the PHY domain
(synchronization delay).
Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 07832509584f..d423d524c05d 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -228,12 +228,23 @@ static int dwc3_core_soft_reset(struct dwc3 *dwc)
do {
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
if (!(reg & DWC3_DCTL_CSFTRST))
- return 0;
+ goto done;
udelay(1);
} while (--retries);
return -ETIMEDOUT;
+
+done:
+ /*
+ * For DWC_usb31 controller, once DWC3_DCTL_CSFTRST bit is cleared,
+ * we must wait at least 50ms before accessing the PHY domain
+ * (synchronization delay). DWC_usb31 Databook section 1.3.2.
+ */
+ if (dwc3_is_usb31(dwc))
+ msleep(50);
+
+ return 0;
}
/*
--
2.11.0
--
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