On Wed, Oct 15, 2014 at 12:06:10PM -0500, Felipe Balbi wrote: > On Wed, Oct 15, 2014 at 10:01:45AM -0700, David Cohen wrote: > > On Wed, Oct 15, 2014 at 09:57:18AM -0700, David Cohen wrote: > > > On Wed, Oct 15, 2014 at 12:00:22AM -0500, Felipe Balbi wrote: > > > > Hi, > > > > > > > > On Tue, Oct 14, 2014 at 01:15:05PM -0700, David Cohen wrote: > > > > > ERRATIC_ERROR interrupt is an event that needs more attention from > > > > > developers than currently implemented, since this indicates a serious > > > > > stability issue. The only way to get warned about it is by selecting the > > > > > maximum driver's verbosity. > > > > > > > > > > This patch increases a bit the error's verbosity. > > > > > > > > > > Signed-off-by: David Cohen <david.a.cohen@xxxxxxxxxxxxxxx> > > > > > --- > > > > > drivers/usb/dwc3/gadget.c | 3 ++- > > > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > > > > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > > > > > index 3818b26bfc05..132e761d62e4 100644 > > > > > --- a/drivers/usb/dwc3/gadget.c > > > > > +++ b/drivers/usb/dwc3/gadget.c > > > > > @@ -2484,7 +2484,8 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc, > > > > > dev_vdbg(dwc->dev, "Start of Periodic Frame\n"); > > > > > break; > > > > > case DWC3_DEVICE_EVENT_ERRATIC_ERROR: > > > > > - dev_vdbg(dwc->dev, "Erratic Error\n"); > > > > > + WARN_ON_ONCE(1); > > > > > + dev_dbg(dwc->dev, "Erratic Error\n"); > > > > > > > > how about: > > > > WARN_ONCE(true, "Erratic Error\n"); > > > > > > > > instead ? > > > > > > When erratic error event happens, in my experience it is usually > > > followed but many of them in a row. It may end up too verbose. > > > > Oops, sorry for my confusion. I read WARN(), not WARN_ONCE() when I read > > for the first time :) > > > > I let the dev_dbg() because it may be useful to get all the occurrences > > in case debug is enabled. But WARN_ONCE() is fine too if you prefer. > > We might WARN_ONCE() and forcibly disconnect from host as the platform > worn't work anymore after Erratic Error happens. Then just make that > clear with "Erratic Error: disconnecting from host\n" or something like > that. That works. I assume calling dwc3_gadget_disconnect_interrupt() from DWC3_DEVICE_EVENT_ERRATIC_ERROR should be enough to disconnect the gadget and propagate the status to userspace. > > The only way to fix erratic error (by fixing code - probably PHY driver) > will require rebooting the platform anyway. At a minimum, you'd have to > unload and reload dwc3.ko, just make sure (if you can reproduce erratic > error easily) modprobe -r dwc3 && modprobe dwc3 still causes dwc3 to > reconnect to host. It does. Forcing soft reset on whole IP is how databook describes to solve it. Br, David > > cheers > > -- > balbi -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
