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
