| Message ID | 1577175825-6424-3-git-send-email-ley.foon.tan@intel.com |
|---|---|
| State | Superseded |
| Delegated to: | Marek Vasut |
| Headers | show |
| Series | reset/usb: Add reset status | expand |
On 12/24/19 9:23 AM, Ley Foon Tan wrote: > 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.tan@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; [...] Can't we implement some sort of "reset_wait_clear()" API instead of open-coding this in the driver ? Or rather, shouldn't the socfpga_reset_deassert wait until the reset was actually de-asserted ? This might be even better, I think it should.
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)
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.tan@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(-)