pinctrl: renesas: r8a77995: Add support for AVB power-source

Add support for configuring the I/O voltage level of the Ethernet AVB
pins on the R-Car D3 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/8f9164487715d8a4898ca651038c0b4d5013764c.1678271030.git.geert+renesas@glider.be

drivers/pinctrl/renesas/pfc-r8a77995.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
@@ -2857,11 +2858,13 @@ static const struct pinmux_cfg_reg pinmux_config_regs[] = {
 
 enum ioctrl_regs {
 	POCCTRL0,
+	POCCTRL2,
 	TDSELCTRL,
 };
 
 static const struct pinmux_ioctrl_reg pinmux_ioctrl_regs[] = {
 	[POCCTRL0] = { 0xe6060380, },
+	[POCCTRL2] = { 0xe6060388, },
 	[TDSELCTRL] = { 0xe60603c0, },
 	{ /* sentinel */ },
 };
@@ -2869,14 +2872,18 @@ static const struct pinmux_ioctrl_reg pinmux_ioctrl_regs[] = {
 
 static int r8a77995_pin_to_pocctrl(unsigned int pin, u32 *pocctrl)
 {
-	int bit = -EINVAL;
-
+	switch (pin) {
+	case RCAR_GP_PIN(3, 0) ... RCAR_GP_PIN(3, 9):
 		*pocctrl = pinmux_ioctrl_regs[POCCTRL0].reg;
+		return 29 - (pin - RCAR_GP_PIN(3, 0));
 
-	if (pin >= RCAR_GP_PIN(3, 0) && pin <= RCAR_GP_PIN(3, 9))
-		bit = 29 - (pin - RCAR_GP_PIN(3, 0));
+	case PIN_VDDQ_AVB0:
+		*pocctrl = pinmux_ioctrl_regs[POCCTRL2].reg;
+		return 0;
 
-	return bit;
+	default:
+		return -EINVAL;
+	}
 }
 
 static const struct pinmux_bias_reg pinmux_bias_regs[] = {