net: phy: allow to expose and i2c controller

Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
bootlin · Apr 1, 2020 · 61645af · 61645af
1 parent 834e2c6
commit 61645af
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Showing 3 changed files with 65 additions and 0 deletions.
diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
@@ -5,6 +5,7 @@
 #include <linux/export.h>
 #include <linux/phy.h>
 #include <linux/of.h>
+#include <linux/i2c.h>
 
 const char *phy_speed_to_str(int speed)
 {
@@ -303,6 +304,61 @@ void phy_resolve_aneg_pause(struct phy_device *phydev)
 }
 EXPORT_SYMBOL_GPL(phy_resolve_aneg_pause);
 
+static int mdio_i2c_master_xfer(struct i2c_adapter *adap,
+			        struct i2c_msg msgs[], int num)
+{
+	struct phy_device *phydev = adap->algo_data;
+
+	if (!phydev->drv->i2c_xfer)
+		return -EOPNOTSUPP;
+
+	return phydev->drv->i2c_xfer(phydev, msgs, num);
+}
+
+static u32 mdio_i2c_func(struct i2c_adapter *adapter)
+{
+	return I2C_FUNC_I2C;
+}
+
+/* I2C support */
+static struct i2c_algorithm mdio_i2c_algo = {
+	.master_xfer	= mdio_i2c_master_xfer,
+	.functionality	= mdio_i2c_func,
+};
+
+int of_phy_init_i2c(struct device *dev, struct device_node *node)
+{
+	struct device_node *i2c_node;
+	struct i2c_adapter *adap;
+	int ret;
+
+	/* This is optional */
+	i2c_node = of_find_node_by_name(node, "i2c-controller");
+	if (!i2c_node)
+		return 0;
+
+	adap = kzalloc(sizeof(*adap), GFP_KERNEL);
+	if (!adap)
+		return -ENOMEM;
+
+	adap->owner = THIS_MODULE;
+	adap->dev.of_node = i2c_node;
+	adap->algo = &mdio_i2c_algo;
+	adap->timeout = msecs_to_jiffies(1000);
+	adap->retries = 3;
+	adap->algo_data = dev;
+	adap->dev.parent = dev;
+	strcpy(adap->name, "mdio-i2c");
+
+	ret = i2c_add_adapter(adap);
+	pr_info("%s : Added mdio i2c adapter : %d\n", __func__, ret);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL(of_phy_init_i2c);
+
 /**
  * phy_resolve_aneg_linkmode - resolve the advertisements into phy settings
  * @phydev: The phy_device struct

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
@@ -767,6 +767,11 @@ struct phylink *phylink_create(struct phylink_config *config,
 
 	pl->cur_link_an_mode = pl->cfg_link_an_mode;
 
+	if (config->type == PHYLINK_NETDEV)
+		of_phy_init_i2c(&pl->netdev->dev, to_of_node(fwnode));
+	else
+		of_phy_init_i2c(pl->dev, to_of_node(fwnode));
+
 	ret = phylink_register_sfp(pl, fwnode);
 	if (ret < 0) {
 		kfree(pl);

diff --git a/include/linux/phy.h b/include/linux/phy.h
@@ -14,6 +14,7 @@
 #include <linux/compiler.h>
 #include <linux/spinlock.h>
 #include <linux/ethtool.h>
+#include <linux/i2c.h>
 #include <linux/linkmode.h>
 #include <linux/mdio.h>
 #include <linux/mii.h>
@@ -652,6 +653,8 @@ struct phy_driver {
 			    struct ethtool_tunable *tuna,
 			    const void *data);
 	int (*set_loopback)(struct phy_device *dev, bool enable);
+
+	int (*i2c_xfer)(struct phy_device *dev, struct i2c_msg msgs[], int num);
 };
 #define to_phy_driver(d) container_of(to_mdio_common_driver(d),		\
 				      struct phy_driver, mdiodrv)
@@ -692,6 +695,7 @@ size_t phy_speeds(unsigned int *speeds, size_t size,
 void of_set_phy_supported(struct phy_device *phydev);
 void of_set_phy_eee_broken(struct phy_device *phydev);
 int phy_speed_down_core(struct phy_device *phydev);
+int of_phy_init_i2c(struct device *dev, struct device_node *node);
 
 /**
  * phy_is_started - Convenience function to check whether PHY is started