Merge branch 'dt_fixed_phy'

Thomas Petazzoni says:

====================
Add DT support for fixed PHYs

Here is a fourth version of the patch set that adds a Device Tree
binding and the related code to support fixed PHYs. I'm hoping to get
this merged in 3.16.

Changes since v3:

 * Rebased on top of v3.15-rc5

 * In patch "net: phy: decouple PHY id and PHY address in fixed PHY
   driver", changed the PHY ID of fixed PHYs from 0xdeadbeef to 0x0,
   as suggested by Grant Likely.

 * Fixed the !CONFIG_PHY_FIXED case in patch "net: phy: extend fixed
   driver with fixed_phy_register()". Noticed by Florian Fainelli.

 * Added Acked-by from Grant Likely and Florian Fainelli on patch
   "net: phy: extend fixed driver with fixed_phy_register()".

 * Reworked the new fixed-link DT binding to be just a sub-node of the
   Ethernet MAC node, and not a node referenced by the 'phy'
   property. This was requested by Grant Likely.

 * Reworked the code implementing the new DT binding to also make it
   accept the old, single property based, DT binding.

 * Added a patch that actually uses the new fixed link DT binding for
   the Armada XP Matrix board.

Changes since v2:

 * Rebased on top of v3.14-rc1, and re-tested on hardware.

 * Removed the RFC tag, since there seems to be some real interest in
   this feature, and the code has gone through several iterations
   already.

 * The error handling in fixed_phy_register() has been fixed.

Changes since v1:

 * Instead of using a 'fixed-link' property inside the Ethernet device
   DT node, with a fairly cryptic succession of integer values, we now
   use a PHY subnode under the Ethernet device DT node, with explicit
   properties to configure the duplex, speed, pause and other PHY
   properties.

 * The PHY address is automatically allocated by the kernel and no
   longer visible in the Device Tree binding.

 * The PHY device is created directly when the network driver calls
   of_phy_connect_fixed_link(), and associated to the PHY DT node,
   which allows the existing of_phy_connect() function to work,
   without the need to use the deprecated of_phy_connect_fixed_link().

Posts of previous versions:

  RFCv1:   http://www.spinics.net/lists/netdev/msg243253.html
  RFCv2:   http://lists.infradead.org/pipermail/linux-arm-kernel/2013-September/196919.html
  PATCHv3: http://www.spinics.net/lists/netdev/msg273117.html
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/fixed-link.txt

+Fixed link Device Tree binding
+------------------------------
+
+Some Ethernet MACs have a "fixed link", and are not connected to a
+normal MDIO-managed PHY device. For those situations, a Device Tree
+binding allows to describe a "fixed link".
+
+Such a fixed link situation is described by creating a 'fixed-link'
+sub-node of the Ethernet MAC device node, with the following
+properties:
+
+* 'speed' (integer, mandatory), to indicate the link speed. Accepted
+  values are 10, 100 and 1000
+* 'full-duplex' (boolean, optional), to indicate that full duplex is
+  used. When absent, half duplex is assumed.
+* 'pause' (boolean, optional), to indicate that pause should be
+  enabled.
+* 'asym-pause' (boolean, optional), to indicate that asym_pause should
+  be enabled.
+
+Example:
+
+ethernet@0 {
+	...
+	fixed-link {
+	      speed = <1000>;
+	      full-duplex;
+	};
+	...
+};

arch/arm/boot/dts/armada-xp-matrix.dts

@@ -61,6 +61,10 @@ sata@a0000 {
 			ethernet@30000 {
 				status = "okay";
 				phy-mode = "sgmii";
+				fixed-link {
+					speed = <1000>;
+					full-duplex;
+				};
 			};
 
 			pcie-controller {

drivers/net/ethernet/marvell/mvneta.c

@@ -2797,11 +2797,24 @@ static int mvneta_probe(struct platform_device *pdev)
 
 	phy_node = of_parse_phandle(dn, "phy", 0);
 	if (!phy_node) {
-		dev_err(&pdev->dev, "no associated PHY\n");
+		if (!of_phy_is_fixed_link(dn)) {
+			dev_err(&pdev->dev, "no PHY specified\n");
 			err = -ENODEV;
 			goto err_free_irq;
 		}
 
+		err = of_phy_register_fixed_link(dn);
+		if (err < 0) {
+			dev_err(&pdev->dev, "cannot register fixed PHY\n");
+			goto err_free_irq;
+		}
+
+		/* In the case of a fixed PHY, the DT node associated
+		 * to the PHY is the Ethernet MAC DT node.
+		 */
+		phy_node = dn;
+	}
+
 	phy_mode = of_get_phy_mode(dn);
 	if (phy_mode < 0) {
 		dev_err(&pdev->dev, "incorrect phy-mode\n");

drivers/net/phy/fixed.c

@@ -21,6 +21,7 @@
 #include <linux/phy_fixed.h>
 #include <linux/err.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 #define MII_REGS_NUM 29
 
@@ -31,7 +32,7 @@ struct fixed_mdio_bus {
 };
 
 struct fixed_phy {
-	int id;
+	int addr;
 	u16 regs[MII_REGS_NUM];
 	struct phy_device *phydev;
 	struct fixed_phy_status status;
@@ -104,8 +105,8 @@ static int fixed_phy_update_regs(struct fixed_phy *fp)
 	if (fp->status.asym_pause)
 		lpa |= LPA_PAUSE_ASYM;
 
-	fp->regs[MII_PHYSID1] = fp->id >> 16;
-	fp->regs[MII_PHYSID2] = fp->id;
+	fp->regs[MII_PHYSID1] = 0;
+	fp->regs[MII_PHYSID2] = 0;
 
 	fp->regs[MII_BMSR] = bmsr;
 	fp->regs[MII_BMCR] = bmcr;
@@ -115,7 +116,7 @@ static int fixed_phy_update_regs(struct fixed_phy *fp)
 	return 0;
 }
 
-static int fixed_mdio_read(struct mii_bus *bus, int phy_id, int reg_num)
+static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)
 {
 	struct fixed_mdio_bus *fmb = bus->priv;
 	struct fixed_phy *fp;
@@ -124,7 +125,7 @@ static int fixed_mdio_read(struct mii_bus *bus, int phy_id, int reg_num)
 		return -1;
 
 	list_for_each_entry(fp, &fmb->phys, node) {
-		if (fp->id == phy_id) {
+		if (fp->addr == phy_addr) {
 			/* Issue callback if user registered it. */
 			if (fp->link_update) {
 				fp->link_update(fp->phydev->attached_dev,
@@ -138,7 +139,7 @@ static int fixed_mdio_read(struct mii_bus *bus, int phy_id, int reg_num)
 	return 0xFFFF;
 }
 
-static int fixed_mdio_write(struct mii_bus *bus, int phy_id, int reg_num,
+static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num,
 			    u16 val)
 {
 	return 0;
@@ -160,7 +161,7 @@ int fixed_phy_set_link_update(struct phy_device *phydev,
 		return -EINVAL;
 
 	list_for_each_entry(fp, &fmb->phys, node) {
-		if (fp->id == phydev->phy_id) {
+		if (fp->addr == phydev->addr) {
 			fp->link_update = link_update;
 			fp->phydev = phydev;
 			return 0;
@@ -171,7 +172,7 @@ int fixed_phy_set_link_update(struct phy_device *phydev,
 }
 EXPORT_SYMBOL_GPL(fixed_phy_set_link_update);
 
-int fixed_phy_add(unsigned int irq, int phy_id,
+int fixed_phy_add(unsigned int irq, int phy_addr,
 		  struct fixed_phy_status *status)
 {
 	int ret;
@@ -184,9 +185,9 @@ int fixed_phy_add(unsigned int irq, int phy_id,
 
 	memset(fp->regs, 0xFF,  sizeof(fp->regs[0]) * MII_REGS_NUM);
 
-	fmb->irqs[phy_id] = irq;
+	fmb->irqs[phy_addr] = irq;
 
-	fp->id = phy_id;
+	fp->addr = phy_addr;
 	fp->status = *status;
 
 	ret = fixed_phy_update_regs(fp);
@@ -203,6 +204,66 @@ int fixed_phy_add(unsigned int irq, int phy_id,
 }
 EXPORT_SYMBOL_GPL(fixed_phy_add);
 
+void fixed_phy_del(int phy_addr)
+{
+	struct fixed_mdio_bus *fmb = &platform_fmb;
+	struct fixed_phy *fp, *tmp;
+
+	list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
+		if (fp->addr == phy_addr) {
+			list_del(&fp->node);
+			kfree(fp);
+			return;
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(fixed_phy_del);
+
+static int phy_fixed_addr;
+static DEFINE_SPINLOCK(phy_fixed_addr_lock);
+
+int fixed_phy_register(unsigned int irq,
+		       struct fixed_phy_status *status,
+		       struct device_node *np)
+{
+	struct fixed_mdio_bus *fmb = &platform_fmb;
+	struct phy_device *phy;
+	int phy_addr;
+	int ret;
+
+	/* Get the next available PHY address, up to PHY_MAX_ADDR */
+	spin_lock(&phy_fixed_addr_lock);
+	if (phy_fixed_addr == PHY_MAX_ADDR) {
+		spin_unlock(&phy_fixed_addr_lock);
+		return -ENOSPC;
+	}
+	phy_addr = phy_fixed_addr++;
+	spin_unlock(&phy_fixed_addr_lock);
+
+	ret = fixed_phy_add(PHY_POLL, phy_addr, status);
+	if (ret < 0)
+		return ret;
+
+	phy = get_phy_device(fmb->mii_bus, phy_addr, false);
+	if (!phy || IS_ERR(phy)) {
+		fixed_phy_del(phy_addr);
+		return -EINVAL;
+	}
+
+	of_node_get(np);
+	phy->dev.of_node = np;
+
+	ret = phy_device_register(phy);
+	if (ret) {
+		phy_device_free(phy);
+		of_node_put(np);
+		fixed_phy_del(phy_addr);
+		return ret;
+	}
+
+	return 0;
+}
+
 static int __init fixed_mdio_bus_init(void)
 {
 	struct fixed_mdio_bus *fmb = &platform_fmb;

drivers/of/of_mdio.c

@@ -14,6 +14,7 @@
 #include <linux/netdevice.h>
 #include <linux/err.h>
 #include <linux/phy.h>
+#include <linux/phy_fixed.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_mdio.h>
@@ -301,3 +302,69 @@ struct phy_device *of_phy_attach(struct net_device *dev,
 	return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
 }
 EXPORT_SYMBOL(of_phy_attach);
+
+#if defined(CONFIG_FIXED_PHY)
+/*
+ * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
+ * support two DT bindings:
+ * - the old DT binding, where 'fixed-link' was a property with 5
+ *   cells encoding various informations about the fixed PHY
+ * - the new DT binding, where 'fixed-link' is a sub-node of the
+ *   Ethernet device.
+ */
+bool of_phy_is_fixed_link(struct device_node *np)
+{
+	struct device_node *dn;
+	int len;
+
+	/* New binding */
+	dn = of_get_child_by_name(np, "fixed-link");
+	if (dn) {
+		of_node_put(dn);
+		return true;
+	}
+
+	/* Old binding */
+	if (of_get_property(np, "fixed-link", &len) &&
+	    len == (5 * sizeof(__be32)))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL(of_phy_is_fixed_link);
+
+int of_phy_register_fixed_link(struct device_node *np)
+{
+	struct fixed_phy_status status = {};
+	struct device_node *fixed_link_node;
+	const __be32 *fixed_link_prop;
+	int len;
+
+	/* New binding */
+	fixed_link_node = of_get_child_by_name(np, "fixed-link");
+	if (fixed_link_node) {
+		status.link = 1;
+		status.duplex = of_property_read_bool(np, "full-duplex");
+		if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
+			return -EINVAL;
+		status.pause = of_property_read_bool(np, "pause");
+		status.asym_pause = of_property_read_bool(np, "asym-pause");
+		of_node_put(fixed_link_node);
+		return fixed_phy_register(PHY_POLL, &status, np);
+	}
+
+	/* Old binding */
+	fixed_link_prop = of_get_property(np, "fixed-link", &len);
+	if (fixed_link_prop && len == (5 * sizeof(__be32))) {
+		status.link = 1;
+		status.duplex = be32_to_cpu(fixed_link_prop[1]);
+		status.speed = be32_to_cpu(fixed_link_prop[2]);
+		status.pause = be32_to_cpu(fixed_link_prop[3]);
+		status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
+		return fixed_phy_register(PHY_POLL, &status, np);
+	}
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL(of_phy_register_fixed_link);
+#endif

include/linux/of_mdio.h

@@ -72,4 +72,19 @@ static inline struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np)
 }
 #endif /* CONFIG_OF */
 
+#if defined(CONFIG_OF) && defined(CONFIG_FIXED_PHY)
+extern int of_phy_register_fixed_link(struct device_node *np);
+extern bool of_phy_is_fixed_link(struct device_node *np);
+#else
+static inline int of_phy_register_fixed_link(struct device_node *np)
+{
+	return -ENOSYS;
+}
+static inline bool of_phy_is_fixed_link(struct device_node *np)
+{
+	return false;
+}
+#endif
+
+
 #endif /* __LINUX_OF_MDIO_H */

include/linux/phy_fixed.h

@@ -9,15 +9,26 @@ struct fixed_phy_status {
 	int asym_pause;
 };
 
+struct device_node;
+
 #ifdef CONFIG_FIXED_PHY
 extern int fixed_phy_add(unsigned int irq, int phy_id,
 			 struct fixed_phy_status *status);
+extern int fixed_phy_register(unsigned int irq,
+			      struct fixed_phy_status *status,
+			      struct device_node *np);
 #else
 static inline int fixed_phy_add(unsigned int irq, int phy_id,
 				struct fixed_phy_status *status)
 {
 	return -ENODEV;
 }
+static inline int fixed_phy_register(unsigned int irq,
+				     struct fixed_phy_status *status,
+				     struct device_node *np)
+{
+	return -ENODEV;
+}
 #endif /* CONFIG_FIXED_PHY */
 
 /*