On Wed, Jun 08, 2016 at 01:12:10PM +0300, Roger Quadros wrote: > Hi, > > On 08/06/16 12:53, Peter Chen wrote: > > On Wed, Jun 08, 2016 at 12:03:40PM +0300, Roger Quadros wrote: > >> +int usb_otg_unregister(struct device *dev) > >> +{ > >> + struct usb_otg *otg; > >> + > >> + mutex_lock(&otg_list_mutex); > >> + otg = usb_otg_get_data(dev); > >> + if (!otg) { > >> + dev_err(dev, "otg: %s: device not in otg list\n", > >> + __func__); > >> + mutex_unlock(&otg_list_mutex); > >> + return -EINVAL; > >> + } > >> + > >> + /* prevent unregister till both host & gadget have unregistered */ > >> + if (otg->host || otg->gadget) { > >> + dev_err(dev, "otg: %s: host/gadget still registered\n", > >> + __func__); > > > > You need to call mutex_unlock here > > Indeed. good catch. > > > >> + > >> +int usb_otg_gadget_ready(struct usb_gadget *gadget, bool ready) > >> +{ > > > > What this API is for? Why need it in this version? > > we moved gadget to otg registration from udc_bind_to_driver() to usb_add_gadget_udc_release(). > This means there is a window when gadget function driver (e.g. g_zero) is not loaded. > We don't want to start the gadget controller in that window. > > usb_otg_gadget_ready() is used by gadget core to notify the otg core when the function driver > is ready or not-ready. > Why you need to move this from gadget's probe to udc's probe? Currently, the sequence of gadget and udc's probe is random, but udc_bind_to_driver is called when udc is ready. -- Best Regards, Peter Chen -- 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