Merge branch 'dp83822-gpio2'

Dimitri Fedrau says:

====================
net: phy: dp83822: Add support for GPIO2 clock output

The DP83822 has several clock configuration options for pins GPIO1, GPIO2
and GPIO3. Clock options include:
  - MAC IF clock
  - XI clock
  - Free-Running clock
  - Recovered clock
This patch adds support for GPIO2, the support for GPIO1 and GPIO3 can be
easily added if needed. Code and device tree bindings are derived from
dp83867 which has a similar feature.

Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
---
Changes in v3:
- Dropped <dt-bindings/net/ti-dp83822.h>
- Moved defines from <dt-bindings/net/ti-dp83822.h> to dp83822.c
- Switched to enum of type string for property ti,gpio2-clk-out and added
  explanation for values, added example.
- Link to v2: https://lore.kernel.org/r/20241211-dp83822-gpio2-clk-out-v2-0-614a54f6acab@liebherr.com

Changes in v2:
- Move MII_DP83822_IOCTRL2 before MII_DP83822_GENCFG
- List case statements together, and have one break at the end.
- Move dp83822->set_gpio2_clk_out = true at the end of the validation
- Link to v1: https://lore.kernel.org/r/20241209-dp83822-gpio2-clk-out-v1-0-fd3c8af59ff5@liebherr.com
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/ti,dp83822.yaml

@@ -96,6 +96,32 @@ properties:
       - master
       - slave
 
+  ti,gpio2-clk-out:
+    description: |
+       DP83822 PHY only.
+       The GPIO2 pin on the DP83822 can be configured as clock output. When
+       omitted, the PHY's default will be left as is.
+
+       - 'mac-if': In MII mode the clock frequency is 25-MHz, in RMII Mode the
+         clock frequency is 50-MHz and in RGMII Mode the clock frequency is
+         25-MHz.
+       - 'xi': XI clock(pass-through clock from XI pin).
+       - 'int-ref': Internal reference clock 25-MHz.
+       - 'rmii-master-mode-ref': RMII master mode reference clock 50-MHz. RMII
+         master mode reference clock is identical to MAC IF clock in RMII master
+         mode.
+       - 'free-running': Free running clock 125-MHz.
+       - 'recovered': Recovered clock is a 125-MHz recovered clock from a
+         connected link partner.
+    $ref: /schemas/types.yaml#/definitions/string
+    enum:
+      - mac-if
+      - xi
+      - int-ref
+      - rmii-master-mode-ref
+      - free-running
+      - recovered
+
 required:
   - reg
 
@@ -110,6 +136,7 @@ examples:
         reg = <0>;
         rx-internal-delay-ps = <1>;
         tx-internal-delay-ps = <1>;
+        ti,gpio2-clk-out = "xi";
       };
     };
 

drivers/net/phy/dp83822.c

@@ -30,6 +30,7 @@
 #define MII_DP83822_FCSCR	0x14
 #define MII_DP83822_RCSR	0x17
 #define MII_DP83822_RESET_CTRL	0x1f
+#define MII_DP83822_IOCTRL2	0x463
 #define MII_DP83822_GENCFG	0x465
 #define MII_DP83822_SOR1	0x467
 
@@ -104,6 +105,18 @@
 #define DP83822_RX_CLK_SHIFT	BIT(12)
 #define DP83822_TX_CLK_SHIFT	BIT(11)
 
+/* IOCTRL2 bits */
+#define DP83822_IOCTRL2_GPIO2_CLK_SRC		GENMASK(6, 4)
+#define DP83822_IOCTRL2_GPIO2_CTRL		GENMASK(2, 0)
+#define DP83822_IOCTRL2_GPIO2_CTRL_CLK_REF	GENMASK(1, 0)
+
+#define DP83822_CLK_SRC_MAC_IF			0x0
+#define DP83822_CLK_SRC_XI			0x1
+#define DP83822_CLK_SRC_INT_REF			0x2
+#define DP83822_CLK_SRC_RMII_MASTER_MODE_REF	0x4
+#define DP83822_CLK_SRC_FREE_RUNNING		0x6
+#define DP83822_CLK_SRC_RECOVERED		0x7
+
 /* SOR1 mode */
 #define DP83822_STRAP_MODE1	0
 #define DP83822_STRAP_MODE2	BIT(0)
@@ -139,6 +152,8 @@ struct dp83822_private {
 	u8 cfg_dac_minus;
 	u8 cfg_dac_plus;
 	struct ethtool_wolinfo wol;
+	bool set_gpio2_clk_out;
+	u32 gpio2_clk_out;
 };
 
 static int dp83822_config_wol(struct phy_device *phydev,
@@ -413,6 +428,15 @@ static int dp83822_config_init(struct phy_device *phydev)
 	int err = 0;
 	int bmcr;
 
+	if (dp83822->set_gpio2_clk_out)
+		phy_modify_mmd(phydev, MDIO_MMD_VEND2, MII_DP83822_IOCTRL2,
+			       DP83822_IOCTRL2_GPIO2_CTRL |
+			       DP83822_IOCTRL2_GPIO2_CLK_SRC,
+			       FIELD_PREP(DP83822_IOCTRL2_GPIO2_CTRL,
+					  DP83822_IOCTRL2_GPIO2_CTRL_CLK_REF) |
+			       FIELD_PREP(DP83822_IOCTRL2_GPIO2_CLK_SRC,
+					  dp83822->gpio2_clk_out));
+
 	if (phy_interface_is_rgmii(phydev)) {
 		rx_int_delay = phy_get_internal_delay(phydev, dev, NULL, 0,
 						      true);
@@ -611,6 +635,7 @@ static int dp83822_of_init(struct phy_device *phydev)
 {
 	struct dp83822_private *dp83822 = phydev->priv;
 	struct device *dev = &phydev->mdio.dev;
+	const char *of_val;
 
 	/* Signal detection for the PHY is only enabled if the FX_EN and the
 	 * SD_EN pins are strapped. Signal detection can only enabled if FX_EN
@@ -623,6 +648,29 @@ static int dp83822_of_init(struct phy_device *phydev)
 		dp83822->fx_enabled = device_property_present(dev,
 							      "ti,fiber-mode");
 
+	if (!device_property_read_string(dev, "ti,gpio2-clk-out", &of_val)) {
+		if (strcmp(of_val, "mac-if") == 0) {
+			dp83822->gpio2_clk_out = DP83822_CLK_SRC_MAC_IF;
+		} else if (strcmp(of_val, "xi") == 0) {
+			dp83822->gpio2_clk_out = DP83822_CLK_SRC_XI;
+		} else if (strcmp(of_val, "int-ref") == 0) {
+			dp83822->gpio2_clk_out = DP83822_CLK_SRC_INT_REF;
+		} else if (strcmp(of_val, "rmii-master-mode-ref") == 0) {
+			dp83822->gpio2_clk_out = DP83822_CLK_SRC_RMII_MASTER_MODE_REF;
+		} else if (strcmp(of_val, "free-running") == 0) {
+			dp83822->gpio2_clk_out = DP83822_CLK_SRC_FREE_RUNNING;
+		} else if (strcmp(of_val, "recovered") == 0) {
+			dp83822->gpio2_clk_out = DP83822_CLK_SRC_RECOVERED;
+		} else {
+			phydev_err(phydev,
+				   "Invalid value for ti,gpio2-clk-out property (%s)\n",
+				   of_val);
+			return -EINVAL;
+		}
+
+		dp83822->set_gpio2_clk_out = true;
+	}
+
 	return 0;
 }