[PATCH 02/03] pinctrl: sh-pfc: r8a7790: Break out USB0 OVC/VBUS

[Magnus Damm]

Hi Laurent,

On Thu, Feb 6, 2014 at 8:01 PM, Laurent Pinchart
<laurent.pinchart at ideasonboard.com> wrote:
> Hi Magnus,
>
> On Friday 31 January 2014 12:10:05 Magnus Damm wrote:
>> On Fri, Jan 31, 2014 at 10:17 AM, Laurent Pinchart wrote:
>> > On Thursday 30 January 2014 08:10:19 Magnus Damm wrote:
>> >> From: Magnus Damm <damm at opensource.se>
>> >>
>> >> Create a new group for the USB0 OVC/VBUS pin by itself. This
>> >> allows us to monitor PWEN as GPIO on the Lager board.
>> >>
>> >> Signed-off-by: Magnus Damm <damm at opensource.se>
>> >> ---
>> >>
>> >>  drivers/pinctrl/sh-pfc/pfc-r8a7790.c |    9 +++++++++
>> >>  1 file changed, 9 insertions(+)
>> >>
>> >> --- 0001/drivers/pinctrl/sh-pfc/pfc-r8a7790.c
>> >> +++ work/drivers/pinctrl/sh-pfc/pfc-r8a7790.c 2014-01-24
>> > 10:23:32.000000000
>> >> +0900 @@ -3231,6 +3231,13 @@ static const unsigned int usb0_pins[] =
>> >>  static const unsigned int usb0_mux[] = {
>> >>       USB0_PWEN_MARK, USB0_OVC_VBUS_MARK,
>> >>  };
>> >> +static const unsigned int usb0_ovc_vbus_pins[] = {
>> >> +     /* OVC/VBUS */
>> >> +     RCAR_GP_PIN(5, 19),
>> >> +};
>> >> +static const unsigned int usb0_ovc_vbus_mux[] = {
>> >> +     USB0_OVC_VBUS_MARK,
>> >> +};
>> >
>> > Another option would have been to split the existing usb0 group in
>> > usb0_pwen and usb0_ovc. I'm not sure which is better though, I'd just
>> > like to know if you had given it a thought.
>>
>> I actually did just that in my first local attempt, but I decided not
>> to since it will only cause potential breakage.
>
> OK. I assume that using PWEN without OVC/VBUS doesn't make sense, right ?

Correct!

>> > Regardless, what about naming the new group usb0_ovc instead of
>> > usb0_ovc_bus to keep names short ?
>>
>> Is there any particular reason why you want shorter names?
>
> When it doesn't reduce clarity I prefer to keep names short, as that makes the
> code easier to read and write, and (slightly) lowers the memory footprint.

That sounds sane. =)

>> From my side, I prefer to keep the names in sync with the data sheet. In
>> this particular case it is a shared pin so OVC is used for Host while VBUS
>> is used for gadget, so if you're proposing to ditch VBUS then this feels
>> somewhat inconsistent with the current gadget use case. =)
>
> I thought the pin was used for over current detection only, but that doesn't
> make sense for function mode, you're right. Let's keep the name as-is then.
>
> Provided PWEN without OVC/VBUS doesn't make sense and won't be needed,
>
> Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

Thanks,

/ magnus