> -----Original Message----- > From: Baolin Wang [mailto:baolin.wang@xxxxxxxxxx] > Sent: Friday, April 08, 2016 7:00 PM > To: Jun Li <jun.li@xxxxxxx> > Cc: balbi@xxxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; sre@xxxxxxxxxx; > dbaryshkov@xxxxxxxxx; dwmw2@xxxxxxxxxxxxx; peter.chen@xxxxxxxxxxxxx; > stern@xxxxxxxxxxxxxxxxxxx; r.baldyga@xxxxxxxxxxx; > yoshihiro.shimoda.uh@xxxxxxxxxxx; lee.jones@xxxxxxxxxx; broonie@xxxxxxxxxx; > ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx; patches@xxxxxxxxxxxxxxxxxxxxxxxxxxx; > linux-pm@xxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; device- > mainlining@xxxxxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v10 1/4] gadget: Introduce the usb charger framework > > Hi Jun, > > >> >> +/* > >> >> + * usb_charger_detect_type() - detect the charger type manually. > >> >> + * @uchger - usb charger device > >> >> + * > >> >> + * Note: You should ensure you need to detect the charger type > >> >> +manually on your > >> >> + * platform. > >> >> + * You should call it at the right gadget state to avoid > >> >> +affecting gadget > >> >> + * enumeration. > >> >> + */ > >> >> +int usb_charger_detect_type(struct usb_charger *uchger) { > >> >> + enum usb_charger_type type; > >> >> + > >> >> + if (WARN(!uchger->charger_detect, > >> >> + "charger detection method should not be NULL")) > >> >> + return -EINVAL; > >> >> + > >> >> + type = uchger->charger_detect(uchger); > >> >> + > >> >> + mutex_lock(&uchger->lock); > >> >> + uchger->type = type; > >> >> + mutex_unlock(&uchger->lock); > >> >> + > >> >> + return 0; > >> >> +} > >> >> +EXPORT_SYMBOL_GPL(usb_charger_detect_type); > >> > > >> > I still recommend have a central place to call > >> > usb_charger_detect_type() to cover real charger detection instead > >> > of leaving this question open to diff users. This can be done after > >> > vbus-on is detected and before do gadget connect. I don't think > >> > this > >> will make your framework complicated. > >> > >> This API is used for detecting the charger type manually (software > >> charger detection), so if user's udc driver is needed to do this, > >> then they can issue it at their right place to make it more flexible. > >> But let us see other people's suggestion. Thanks. > > > > Ok, actually this API can be used for what ever charger detection > > type, user can implement any method(manual detection, directly read > > result from some HW...what ever) in uchger->charger_detect(), target > > is > > But reading result from some HW dose not means *detect*, actually is *get*. > We can not mix them together with the different semantics. It doesn’t matter here, you already define the _get_ API for just read the charger type from the saved value(uchger->type), so we can think the API to make uchger->type from UNKNOW to ONE KNOWN type is *detect*, because we don't need 2 separate API one for *get* type from HW and another one for *detect* from HW, only one API involve HW access is enough. - Detect: (write to and) read from HW to get the charger type, save to uchger->type; - Get: read the charger type from uchger->type. > > > to have the charger type and set uchger->type, then you no need to add > > the comments/description to limit it usage. Also I do see there is > possible central place to do this. > > > > -- > Baolin.wang > Best Regards ��.n��������+%������w��{.n�����{���)�� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
