[PATCH v2 1/3] pinctrl: rzg2l: Support 2.5V PVDD for Ethernet interfaces

[Paul Barker]

The Ethenet interfaces on the Renesas RZ/G2L SoC family can operate at
multiple power supply voltages: 3.3V (default value), 2.5V and 1.8V.

rzg2l_pinconf_set() is extended to support the 2.5V setting, with a
check to ensure this is only used on Ethernet interfaces as it is not
supported on the SD & QSPI interfaces.

While we're modifying rzg2l_pinconf_set(), drop the unnecessary default
value for pwr_reg as it is set in every branch of the following if
condition.

Signed-off-by: Paul Barker <paul.barker.ct at bp.renesas.com>
---
Changes v1->v2:
  - Split out of series adding RZ/G2L Ethernet support [1]

[1]: https://lore.kernel.org/all/20241024152448.102-1-paul.barker.ct@bp.renesas.com/

 drivers/pinctrl/renesas/rzg2l-pfc.c | 49 ++++++++++++++++++++---------
 include/renesas/rzg2l-pfc.h         |  2 ++
 2 files changed, 37 insertions(+), 14 deletions(-)

diff --git a/drivers/pinctrl/renesas/rzg2l-pfc.c b/drivers/pinctrl/renesas/rzg2l-pfc.c
index e88ec1c18373..0098e2d52d57 100644
--- a/drivers/pinctrl/renesas/rzg2l-pfc.c
+++ b/drivers/pinctrl/renesas/rzg2l-pfc.c
@@ -394,18 +394,10 @@ static int rzg2l_pinconf_set(struct udevice *dev, unsigned int pin_selector,
 	}
 
 	case PIN_CONFIG_POWER_SOURCE: {
-		u32 pwr_reg = 0x0;
+		bool support_2500 = false;
+		u32 pwr_reg;
+		u32 value;
 
-		/* argument is in mV */
-		if (argument != 1800 && argument != 3300) {
-			dev_err(dev, "Invalid mV %u\n", argument);
-			return -EINVAL;
-		}
-
-		/*
-		 * TODO: PIN_CFG_IO_VMC_ETH0 & PIN_CFG_IO_VMC_ETH1 will be
-		 * handled when the RZ/G2L Ethernet driver is added.
-		 */
 		if (cfg & PIN_CFG_IO_VMC_SD0) {
 			dev_dbg(dev, "port off %u:%u set SD_CH 0 PVDD=%u\n",
 				port_offset, pin, argument);
@@ -418,13 +410,42 @@ static int rzg2l_pinconf_set(struct udevice *dev, unsigned int pin_selector,
 			dev_dbg(dev, "port off %u:%u set QSPI PVDD=%u\n",
 				port_offset, pin, argument);
 			pwr_reg = QSPI;
+		} else if (cfg & PIN_CFG_IO_VMC_ETH0) {
+			dev_dbg(dev, "port off %u:%u set ETH0 PVDD=%u\n",
+				port_offset, pin, argument);
+			pwr_reg = ETH_POC(0);
+			support_2500 = true;
+		} else if (cfg & PIN_CFG_IO_VMC_ETH1) {
+			dev_dbg(dev, "port off %u:%u set ETH1 PVDD=%u\n",
+				port_offset, pin, argument);
+			pwr_reg = ETH_POC(1);
+			support_2500 = true;
 		} else {
-			dev_dbg(dev, "pin power source is not selectable\n");
+			dev_dbg(dev, "port off %u:%u PVDD is not selectable\n",
+				port_offset, pin);
+			return -EINVAL;
+		}
+
+		/* argument is in mV */
+		switch (argument) {
+		case 1800:
+			value = PVDD_1800;
+			break;
+		case 3300:
+			value = PVDD_3300;
+			break;
+		case 2500:
+			if (support_2500) {
+				value = PVDD_2500;
+				break;
+			}
+			fallthrough;
+		default:
+			dev_err(dev, "Invalid mV %u\n", argument);
 			return -EINVAL;
 		}
 
-		writel((argument == 1800) ? PVDD_1800 : PVDD_3300,
-		       data->base + pwr_reg);
+		writel(value, data->base + pwr_reg);
 		break;
 	}
 
diff --git a/include/renesas/rzg2l-pfc.h b/include/renesas/rzg2l-pfc.h
index 2df17ece2a31..d1015b1d2ac1 100644
--- a/include/renesas/rzg2l-pfc.h
+++ b/include/renesas/rzg2l-pfc.h
@@ -77,9 +77,11 @@
 #define IEN(n)			(0x1800 + (n) * 8)
 #define PWPR			0x3014
 #define SD_CH(n)		(0x3000 + (n) * 4)
+#define ETH_POC(ch)		(0x300c + (ch) * 4)
 #define QSPI			0x3008
 
 #define PVDD_1800		1	/* I/O domain voltage <= 1.8V */
+#define PVDD_2500		2	/* I/O domain voltage 2.5V */
 #define PVDD_3300		0	/* I/O domain voltage >= 3.3V */
 
 #define PWPR_B0WI		BIT(7)	/* Bit Write Disable */
-- 
2.43.0