Merge branch 'dp83826'

Jérémie Dautheribes says:

====================
Add support for TI DP83826 configuration

This short patch series introduces the possibility of overriding
some parameters which are latched by default by hardware straps on the
TI DP83826 PHY.

The settings that can be overridden include:
  - Configuring the PHY in either MII mode or RMII mode.
  - When in RMII mode, configuring the PHY in RMII slave mode or RMII
  master mode.

The RMII master/slave mode is TI-specific and determines whether the PHY
operates from a 25MHz reference clock (master mode) or from a 50MHz
reference clock (slave mode).

While these features should be supported by all the TI DP8382x family,
I have only been able to test them on TI DP83826 hardware.  Therefore,
support has been added specifically for this PHY in this patch series.
====================

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

2 files changed, 60 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/net/ti,dp83822.yaml b/Documentation/devicetree/bindings/net/ti,dp83822.yaml
index 8f4350be689c..8f23254c0458 100644
--- a/Documentation/devicetree/bindings/net/ti,dp83822.yaml
+++ b/Documentation/devicetree/bindings/net/ti,dp83822.yaml
@@ -80,6 +80,22 @@ properties:
            10625, 11250, 11875, 12500, 13125, 13750, 14375, 15000]
     default: 10000
 
+  ti,rmii-mode:
+    description: |
+       If present, select the RMII operation mode. Two modes are
+       available:
+         - RMII master, where the PHY operates from a 25MHz clock reference,
+         provided by a crystal or a CMOS-level oscillator
+         - RMII slave, where the PHY operates from a 50MHz clock reference,
+         provided by a CMOS-level oscillator
+       The RMII operation mode can also be configured by its straps.
+       If the strap pin is not set correctly or not set at all, then this can be
+       used to configure it.
+    $ref: /schemas/types.yaml#/definitions/string
+    enum:
+      - master
+      - slave
+
 required:
   - reg
 
diff --git a/drivers/net/phy/dp83822.c b/drivers/net/phy/dp83822.c
index 30f2616ab1c2..edc39ae4c241 100644
--- a/drivers/net/phy/dp83822.c
+++ b/drivers/net/phy/dp83822.c
@@ -100,6 +100,8 @@
 #define DP83822_WOL_CLR_INDICATION BIT(11)
 
 /* RCSR bits */
+#define DP83822_RMII_MODE_EN	BIT(5)
+#define DP83822_RMII_MODE_SEL	BIT(7)
 #define DP83822_RGMII_MODE_EN	BIT(9)
 #define DP83822_RX_CLK_SHIFT	BIT(12)
 #define DP83822_TX_CLK_SHIFT	BIT(11)
@@ -494,12 +496,54 @@ static int dp83822_config_init(struct phy_device *phydev)
 	return dp8382x_disable_wol(phydev);
 }
 
+static int dp83826_config_rmii_mode(struct phy_device *phydev)
+{
+	struct device *dev = &phydev->mdio.dev;
+	const char *of_val;
+	int ret;
+
+	if (!device_property_read_string(dev, "ti,rmii-mode", &of_val)) {
+		if (strcmp(of_val, "master") == 0) {
+			ret = phy_clear_bits_mmd(phydev, DP83822_DEVADDR, MII_DP83822_RCSR,
+						 DP83822_RMII_MODE_SEL);
+		} else if (strcmp(of_val, "slave") == 0) {
+			ret = phy_set_bits_mmd(phydev, DP83822_DEVADDR, MII_DP83822_RCSR,
+					       DP83822_RMII_MODE_SEL);
+		} else {
+			phydev_err(phydev, "Invalid value for ti,rmii-mode property (%s)\n",
+				   of_val);
+			ret = -EINVAL;
+		}
+
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static int dp83826_config_init(struct phy_device *phydev)
 {
 	struct dp83822_private *dp83822 = phydev->priv;
 	u16 val, mask;
 	int ret;
 
+	if (phydev->interface == PHY_INTERFACE_MODE_RMII) {
+		ret = phy_set_bits_mmd(phydev, DP83822_DEVADDR, MII_DP83822_RCSR,
+				       DP83822_RMII_MODE_EN);
+		if (ret)
+			return ret;
+
+		ret = dp83826_config_rmii_mode(phydev);
+		if (ret)
+			return ret;
+	} else {
+		ret = phy_clear_bits_mmd(phydev, DP83822_DEVADDR, MII_DP83822_RCSR,
+					 DP83822_RMII_MODE_EN);
+		if (ret)
+			return ret;
+	}
+
 	if (dp83822->cfg_dac_minus != DP83826_CFG_DAC_MINUS_DEFAULT) {
 		val = FIELD_PREP(DP83826_VOD_CFG1_MINUS_MDI_MASK, dp83822->cfg_dac_minus) |
 		      FIELD_PREP(DP83826_VOD_CFG1_MINUS_MDIX_MASK,