On Tue, Apr 26, 2016 at 05:11:36AM +0000, Jun Li wrote: > Hi > > > -----Original Message----- > > From: Peter Chen [mailto:hzpeterchen@xxxxxxxxx] > > Sent: Tuesday, April 26, 2016 11:47 AM > > To: Jun Li <jun.li@xxxxxxx> > > Cc: Roger Quadros <rogerq@xxxxxx>; stern@xxxxxxxxxxxxxxxxxxx; > > balbi@xxxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; peter.chen@xxxxxxxxxxxxx; > > dan.j.williams@xxxxxxxxx; jun.li@xxxxxxxxxxxxx; > > mathias.nyman@xxxxxxxxxxxxxxx; tony@xxxxxxxxxxx; Joao.Pinto@xxxxxxxxxxxx; > > abrestic@xxxxxxxxxxxx; r.baldyga@xxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; > > linux-kernel@xxxxxxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH v6 07/12] usb: otg: add OTG/dual-role core > > > > On Tue, Apr 26, 2016 at 02:07:56AM +0000, Jun Li wrote: > > > > +struct usb_otg *usb_otg_register(struct device *dev, > > > > + struct usb_otg_config *config) { > > > > + struct usb_otg *otg; > > > > + struct otg_wait_data *wait; > > > > + int ret = 0; > > > > + > > > > + if (!dev || !config || !config->fsm_ops) > > > > + return ERR_PTR(-EINVAL); > > > > + > > > > + /* already in list? */ > > > > + mutex_lock(&otg_list_mutex); > > > > + if (usb_otg_get_data(dev)) { > > > > + dev_err(dev, "otg: %s: device already in otg list\n", > > > > + __func__); > > > > + ret = -EINVAL; > > > > + goto unlock; > > > > + } > > > > + > > > > + /* allocate and add to list */ > > > > + otg = kzalloc(sizeof(*otg), GFP_KERNEL); > > > > + if (!otg) { > > > > + ret = -ENOMEM; > > > > + goto unlock; > > > > + } > > > > + > > > > + otg->dev = dev; > > > > + otg->caps = config->otg_caps; > > > > + > > > > + if ((otg->caps->hnp_support || otg->caps->srp_support || > > > > + otg->caps->adp_support) && !config->otg_work) > > > > + dev_info(dev, "otg: limiting to dual-role\n"); > > > > > > dev_err, this should be an error. > > > > The condition may be wrong, but it is an information to show that current > > OTG is dual-role. > > This should not happen in any correct design, I even doubt if we > should try to continue by "downgrade" it to be duel role, currently > the only example user is dual role, so doing like this can't be > tested by real case, this downgrade is not so easy like we image, > at least for chipidea otg driver, simply replace a queue worker may > not work, as we have much more difference between the 2 configs. > Would you show more why chipidea can't work just replace the work item, and see if anything we still can improve for this framework? -- 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
