In Cyclone 5 SoC platform, the first USB probing is failed but second
probing is success. DWC2 driver read gsnpsid register right after de-assert
reset, but controller is not ready yet and it returns gsnpsid 0.
Polling reset status after de-assert reset to solve the issue.
Retry with this fix more than 10 times without issue.
=> usb reset
resetting USB...
Bus usb@ffb40000: usb probe
SNPSID invalid (not DWC2 OTG device): 00000000
Port not available.
=> usb reset
resetting USB...
Bus usb@ffb40000: usb probe
scanning bus usb@ffb40000 for devices... 2 USB Device(s) found
scanning usb for storage devices... 1 Storage Device(s) found
Signed-off-by: Ley Foon Tan <ley.foon....@intel.com>
---
v2:
- Change from constant delay to poll for reset status.
---
drivers/usb/host/dwc2.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
index b9c56f763b..1bc41990ee 100644
--- a/drivers/usb/host/dwc2.c
+++ b/drivers/usb/host/dwc2.c
@@ -1132,6 +1132,7 @@ int _submit_int_msg(struct dwc2_priv *priv, struct
usb_device *dev,
static int dwc2_reset(struct udevice *dev)
{
int ret;
+ int i = 1000;
struct dwc2_priv *priv = dev_get_priv(dev);
ret = reset_get_bulk(dev, &priv->resets);
@@ -1153,7 +1154,14 @@ static int dwc2_reset(struct udevice *dev)
return ret;
}
- return 0;
+ /* Poll until reset is completed. */
+ do {
+ ret = reset_status(&priv->resets.resets[0]);
+ if (!ret)
+ return 0;
+ } while (i--);
+
+ return -ETIMEDOUT;
}
static int dwc2_init_common(struct udevice *dev, struct dwc2_priv *priv)
--
2.19.0
