pinctrl: renesas: r8a77970: Add support for AVB power-source

Add support for configuring the I/O voltage level of the Ethernet AVB
pins on the R-Car V3M SoC.  "PIN_VDDQ_AVB0" can be configured for 2.5V
or 3.3V operation.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/eb4db82bdeb67507a1a77f63b9d90280d6f38ba4.1678271030.git.geert+renesas@glider.be

drivers/pinctrl/renesas/pfc-r8a77970.c

@@ -34,7 +34,8 @@
 	PIN_NOGP_CFG(TCK, "TCK", fn, SH_PFC_PIN_CFG_PULL_UP),		\
 	PIN_NOGP_CFG(TDI, "TDI", fn, SH_PFC_PIN_CFG_PULL_UP),		\
 	PIN_NOGP_CFG(TMS, "TMS", fn, SH_PFC_PIN_CFG_PULL_UP),		\
-	PIN_NOGP_CFG(TRST_N, "TRST#", fn, SH_PFC_PIN_CFG_PULL_UP)
+	PIN_NOGP_CFG(TRST_N, "TRST#", fn, SH_PFC_PIN_CFG_PULL_UP),	\
+	PIN_NOGP_CFG(VDDQ_AVB0, "VDDQ_AVB0", fn, SH_PFC_PIN_CFG_IO_VOLTAGE_25_33)
 
 /*
  * F_() : just information
@@ -2364,19 +2365,30 @@ static int r8a77970_pin_to_pocctrl(unsigned int pin, u32 *pocctrl)
 {
 	int bit = pin & 0x1f;
 
-	*pocctrl = pinmux_ioctrl_regs[POCCTRL0].reg;
-	if (pin >= RCAR_GP_PIN(0, 0) && pin <= RCAR_GP_PIN(0, 21))
+	switch (pin) {
+	case RCAR_GP_PIN(0, 0) ... RCAR_GP_PIN(0, 21):
+		*pocctrl = pinmux_ioctrl_regs[POCCTRL0].reg;
 		return bit;
-	if (pin >= RCAR_GP_PIN(2, 0) && pin <= RCAR_GP_PIN(2, 9))
+
+	case RCAR_GP_PIN(2, 0) ... RCAR_GP_PIN(2, 9):
+		*pocctrl = pinmux_ioctrl_regs[POCCTRL0].reg;
 		return bit + 22;
 
-	*pocctrl = pinmux_ioctrl_regs[POCCTRL1].reg;
-	if (pin >= RCAR_GP_PIN(2, 10) && pin <= RCAR_GP_PIN(2, 16))
+	case RCAR_GP_PIN(2, 10) ... RCAR_GP_PIN(2, 16):
+		*pocctrl = pinmux_ioctrl_regs[POCCTRL1].reg;
 		return bit - 10;
-	if (pin >= RCAR_GP_PIN(3, 0) && pin <= RCAR_GP_PIN(3, 16))
+
+	case RCAR_GP_PIN(3, 0) ... RCAR_GP_PIN(3, 16):
+		*pocctrl = pinmux_ioctrl_regs[POCCTRL1].reg;
 		return bit + 7;
 
-	return -EINVAL;
+	case PIN_VDDQ_AVB0:
+		*pocctrl = pinmux_ioctrl_regs[POCCTRL2].reg;
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
 }
 
 static const struct pinmux_bias_reg pinmux_bias_regs[] = {