Re: [PATCH 3/3] pinctrl: sh-pfc: r8a7794: Implement voltage switching for SDHI

[Simon Horman <horms@xxxxxxxxxxxx>]

On Fri, Sep 09, 2016 at 10:08:03AM +0200, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Thu, Sep 8, 2016 at 1:36 PM, Simon Horman <horms+renesas@xxxxxxxxxxxx> wrote:
> > All the SHDIs can operate with either 3.3V or 1.8V signals, depending
> > on negotiation with the card.
> >
> > Based on work by Wolfram Sang for the r8a7790.
> >
> > Cc: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> 
> Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> 
> > ---
> >  drivers/pinctrl/sh-pfc/pfc-r8a7794.c | 34 +++++++++++++++++++++++++++++++++-
> >  1 file changed, 33 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/pinctrl/sh-pfc/pfc-r8a7794.c b/drivers/pinctrl/sh-pfc/pfc-r8a7794.c
> > index 8bc2cf0c594e..c02b367837b7 100644
> > --- a/drivers/pinctrl/sh-pfc/pfc-r8a7794.c
> > +++ b/drivers/pinctrl/sh-pfc/pfc-r8a7794.c
> > @@ -5160,8 +5162,38 @@ static const struct pinmux_cfg_reg pinmux_config_regs[] = {
> >         { },
> >  };
> >
> > +static int r8a7794_pin_to_pocctrl(struct sh_pfc *pfc, unsigned int pin, u32 *pocctrl)
> > +{
> > +       if (pin < RCAR_GP_PIN(6, 0) || pin > RCAR_GP_PIN(6, 23))
> > +               return -EINVAL;
> > +
> > +       *pocctrl = 0xe606006c;
> > +
> > +       /* GP6_16-23 -> bits 31-24 of pocctrl
> > +        * GP6_06    -> bit  23    of pocctrl
> > +        * GP6_00-05 -> bits 22-17 of pocctrl
> > +        * GP6_07    -> bit  16    of pocctrl
> > +        * GP6_14    -> bit  15    of pocctrl
> > +        * GP6_08-13 -> bits 14-09 of pocctrl
> > +        * GP6_15    -> bit  08    of pocctrl
> > +        */
> > +       if (pin == RCAR_GP_PIN(6, 6) || pin == RCAR_GP_PIN(6, 14))
> > +               return 31 - 2 - (pin & 0x1f);
> > +       else if (pin == RCAR_GP_PIN(6, 7) || pin == RCAR_GP_PIN(6, 15))
> > +               return 31 - 8 - (pin & 0x1f);
> > +       else if (pin < RCAR_GP_PIN(6, 14))
> > +               return 31 - 9 - (pin & 0x1f);
> > +       else
> > +               return 31 + 16 - (pin & 0x1f);
> 
> While your code is correct, I think it's easier for the casual reader to use
> a plain switch () statement, and let the optimizer handle the rest.

Like this? If so I don't particularly mind but it doesn't seem clearer to
me.

+static int r8a7794_pin_to_pocctrl(struct sh_pfc *pfc, unsigned int pin, u32 *pocctrl)
+{
+	*pocctrl = 0xe606006c;
+
+	switch (pin) {
+	case RCAR_GP_PIN(6, 0):
+		return 22;
+	case RCAR_GP_PIN(6, 1):
+		return 21;
+	case RCAR_GP_PIN(6, 2):
+		return 20;
+	case RCAR_GP_PIN(6, 3):
+		return 19;
+	case RCAR_GP_PIN(6, 4):
+		return 18;
+	case RCAR_GP_PIN(6, 5):
+		return 17;
+	case RCAR_GP_PIN(6, 6):
+		return 23;
+	case RCAR_GP_PIN(6, 7):
+		return 16;
+	case RCAR_GP_PIN(6, 8):
+		return 14;
+	case RCAR_GP_PIN(6, 9):
+		return 13;
+	case RCAR_GP_PIN(6, 10):
+		return 12;
+	case RCAR_GP_PIN(6, 11):
+		return 11;
+	case RCAR_GP_PIN(6, 12):
+		return 10;
+	case RCAR_GP_PIN(6, 13):
+		return 9;
+	case RCAR_GP_PIN(6, 14):
+		return 15;
+	case RCAR_GP_PIN(6, 15):
+		return 8;
+	case RCAR_GP_PIN(6, 16):
+		return 31;
+	case RCAR_GP_PIN(6, 17):
+		return 30;
+	case RCAR_GP_PIN(6, 18):
+		return 29;
+	case RCAR_GP_PIN(6, 19):
+		return 28;
+	case RCAR_GP_PIN(6, 20):
+		return 27;
+	case RCAR_GP_PIN(6, 21):
+		return 26;
+	case RCAR_GP_PIN(6, 22):
+		return 25;
+	case RCAR_GP_PIN(6, 23):
+		return 24;
+	}
+
+	return -EINVAL;
+}
+
+static const struct sh_pfc_soc_operations r8a7794_pinmux_ops = {
+	.pin_to_pocctrl = r8a7794_pin_to_pocctrl,
+};
+
 const struct sh_pfc_soc_info r8a7794_pinmux_info = {
 	.name = "r8a77940_pfc",
+	.ops = &r8a7794_pinmux_ops,
 	.unlock_reg = 0xe6060000, /* PMMR */
 
 	.function = { PINMUX_FUNCTION_BEGIN, PINMUX_FUNCTION_END },
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