Re: [PATCH] pinctrl: sh-pfc: Retain TDSELCTRL register across suspend/resume

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Marek,

On Mon, Feb 18, 2019 at 2:38 PM Marek Vasut <marek.vasut@xxxxxxxxx> wrote:
> On 2/18/19 2:32 PM, Geert Uytterhoeven wrote:
> >>>>  struct pinmux_data_reg {
> >>>>         u32 reg;
> >>>>         u8 reg_width;
> >>>> @@ -270,6 +274,7 @@ struct sh_pfc_soc_info {
> >>>>         const struct pinmux_drive_reg *drive_regs;
> >>>>         const struct pinmux_bias_reg *bias_regs;
> >>>>         const struct pinmux_ioctrl_reg *ioctrl_regs;
> >>>> +       const struct pinmux_tdsel_reg *tdsel_regs;
> >>>>         const struct pinmux_data_reg *data_regs;
> >>>>
> >>>>         const u16 *pinmux_data;
> >>>
> >>> Is there any special reason why you added a new block of registers with
> >>> separate handling, instead of adding TDSEL to the existing
> >>> pinmux_ioctrl_reg[] arrays, which list other IOCTRL registers like
> >>> POCCTRL?
> >>
> >> For one, It's unrelated register to POCCTRL, so I don't want to mix them
> >
> > That's why the array is called pinmux_ioctrl_reg[], not pinmux_pocctrl_reg[]:
> > it is meant to cover various I/O control registers, including POCCTRL and
> > TDSEL, to be saved/restored for PSCI system suspend.
>
> I thought the array is called pinmux_ioctrl_reg[] because that's what
> the pocctrl was called in older datasheets ? At least that's how you
> explained it on IRC last time.

Ah, that's where the misunderstanding comes from: both POCCTRLx and
TDSELy registers are sometimes called IOCTRLz registers.

> >> together. The other reason is this r8a779*_pin_to_pocctrl(), which uses
> >> the ioctrl_regs[] array ; if I added the TDSEL there, that'd just make
> >> things extra confusing.
> >
> > How r8a779*_pin_to_pocctrl() gets the registers is an implementation detail,
> > IMHO (The function used to contain hardcoded register addresses).
> >
> > So I think you should just add the TDSEL registers to pinmux_ioctrl_reg[].
>
> If that's what you think is better and makes the driver less confusing,
> sure ...

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds