Hi, On Wed, Oct 30, 2013 at 12:54:15PM -0500, Felipe Balbi wrote: > On Wed, Oct 30, 2013 at 03:17:46PM +0100, Johannes Stezenbach wrote: > > I'm testing dwc3 with g_zero and noticed that errors > > seem to stick even after SET_CONFIGURATION/SET_INTERFACE. > > > > In f_sourcesink.c, check_read_data() calls usb_ep_set_halt() > > if the data does not match the expected values, and > > sourcesink_set_alt() indirectly calls usb_ep_disable() > > and usb_ep_enable(). > > > > Now, include/linux/usb/gadget.h comments for usb_ep_enable() > > are not 100% clear wrt STALL, except "making it usable" > > sounds like it should clear it. However, usb_ep_set_halt() > > comments states: > > > > * Note that while an endpoint CLEAR_FEATURE will be invisible to the > > * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the > > * current altsetting, see usb_ep_clear_halt(). When switching altsettings, > > * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints. > > > > That suggests to me that sourcesink_set_alt() is correct to > > simply call usb_ep_enable(), i.e. no explicit usb_ep_clear_halt() > > is needed? If so it would mean dwc3 ep_enable() is buggy. > > we clear those flags on usb_ep_disable(). You can't enable an endpoint > which is already enabled. And you can see that when you're going to > switch alt settings, f_sourcesink calls disable_source_sink() which will > call disable_endpoints() which will disable each and every endpoint, > thus clearing the such flags. > > Do you have any patches on f_sourcesink which might have caused this > bug ? No patches, but maybe out of date code. However, I'm looking at current git master, I see you clear dep->flags but I don't see any dwc3_send_gadget_ep_cmd(DWC3_DEPCMD_CLEARSTALL)? Thanks, Johannes -- 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
