On Thu, May 08, 2014 at 06:42:53PM +0000, suresh.gupta@xxxxxxxxxxxxx wrote: > > > And Host might be attach after system bootup or after driver > > > initialization. So putting this check in probe will not help much. > > > > If the host is attached after the driver was initialised, the interrupt > > will trigger and the driver will get notified that VBUS appeared and > > everything will go smooth, at least that's how it should work (I do not > > have any board handy to real-life check that, but AFAICT that's the > > intent of the current code). > > If is go through the code flow starting from usb_composite_probe the sequence is > usb_composite_probe->usb_gadget_probe_driver->udc_bind_to_driver-> > udc_bind_to_driver->usb_gadget_udc_start->fsl_udc_start->usbcmd=RUN > udc_bind_to_driver->usb_gadget_connect->fsl_pullup > > The function fsl_pullup make usbcmd=STOP if my fix is not there and if controller > is stopped we do not get any interrupt. Are you really sure we can't get async VBUS state change notifications until controller has USB_CMD_RUN_STOP bit set (and the same bit actually controls internal 1.5k dataline pullup)? If yes, I guess it means we need to check VBUS state _every_ time we set that bit to sync the vbus_active variable with the actual hardware state (unless an external OTG PHY is used and VBUS pad state is irrelevant)? > > I actually do not have any iMX demoboards at all, I've only got some > > custom-designed i.MX25 boards where I can't control VBUS, it's > > permanently pulled up. > > > > But I was fixing the problem that was clearly, 100% reproducibly > > happening when VBUS was applied before the interrupt was configured. So > > Wait a minute, are you using OTG. If your VBUS is permanently pulled up, that > means you are only Gadget(I might miss something) then why you use OTG mode. I'm using FSL_USB2_DR_DEVICE mode (FSL_USB2_PHY_UTMI phy_mode), so the OTG controller should always work in the device mode only. > > what exactly do you mean here? Do you mean this check I've added doesn't > > fix the bug? Or do you mean this bug should be fixed somehow else? Or do > > What expertly my concern is, probe is not proper place to check VBUS valid. > I think we should wait to hear what Balbi has to say. Yes, I hope he can understand both of us :) -- Be free, use free (http://www.gnu.org/philosophy/free-sw.html) software! mailto:fercerpav@xxxxxxxxx -- 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
