On Mon, Jun 13, 2016 at 10:37:59AM +0300, Roger Quadros wrote: > On 13/06/16 10:20, Peter Chen wrote: > > On Mon, Jun 13, 2016 at 10:14:31AM +0300, Roger Quadros wrote: > >> On 12/06/16 14:36, Peter Chen wrote: > >>> On Fri, Jun 10, 2016 at 04:07:22PM +0300, Roger Quadros wrote: > >>>> > >>>> +/** > >>>> + * usb_otg_add_gadget_udc - adds a new gadget to the udc class driver list > >>>> + * @parent: the parent device to this udc. Usually the controller > >>>> + * driver's device. > >>> > >>> It seems it should be udc device > >> > >> Parent and udc->dev are not the same right? > > > > Sure, udc's parent is otg device. > > > >> > >> I guess i'll omit the second statement to avoid confusion. So. > >> > >> @parent: the parent device to this udc. > > > > Where you call below APIs? It seems to be a udc driver, right? > > So, when you try to get "otg-controller" from the node, this node > > should be udc. > > @parent is actually the device that represents the USB Device controller > in the device tree. When you call usb_add_gadget_udc_release() a new > udc->dev device is created as it's child. > > See explanation for the @parent argument in usb_add_gadget_udc_release(). > As we want to keep the parent argument identical to that I will not make > any changes then. Oh, yes. The parent should be glue layer udc device or the dual-role controller device. Peter > > > > > /** > > * usb_otg_add_gadget_udc - adds a new gadget to the udc class driver list > > * @parent: the parent device to this udc. Usually the controller > > * driver's device. > > * @gadget: the gadget to be added to the list > > * @otg_dev: the OTG controller device > > * > > * If otg_dev is NULL then device tree node is checked > > * for OTG controller via the otg-controller property. > > * Returns zero on success, negative errno otherwise. > > */ > > int usb_otg_add_gadget_udc(struct device *parent, struct usb_gadget *gadget, > > struct device *otg_dev) > > { > > if (!otg_dev) { > > gadget->otg_dev = of_usb_get_otg(parent->of_node); > > if (!gadget->otg_dev) > > return -ENODEV; > > } else { > > gadget->otg_dev = otg_dev; > > } > > > > return usb_add_gadget_udc_release(parent, gadget, NULL); > > } > > EXPORT_SYMBOL_GPL(usb_otg_add_gadget_udc); > > > > -- > cheers, > -roger -- 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