[PATCH net-next v2 05/12] net: dsa: allow for more complex PHY setups

[Florian Fainelli <f.fainelli@gmail.com>]

Modify the DSA slave interface to be bound to an arbitray PHY, not just
the ones that are available as child PHY devices of the switch MDIO bus.

This allows us for instance to have external PHYs connected to a
separate MDIO bus, but yet also connected to a given switch port.

Under certain configurations, the physical port mask might not be a 1:1
mapping to the MII PHYs mask. This is the case, if e.g: Port 1 of the
switch is used and connects to a PHY at a MDIO address different than 1.

Introduce a phys_mii_mask variable which allows driver to implement and
divert their own MDIO read/writes operations for a subset of the MDIO
PHY addresses.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes in v2:
- introduce phys_mii_mask to allow switch drivers to divert MDIO operations
  for some PHY addresses

- use the latest fixed PHY API
- iron out non-OF setups

 include/net/dsa.h  |  1 +
 net/dsa/dsa.c      |  5 ++++
 net/dsa/dsa_priv.h |  4 +++
 net/dsa/slave.c    | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++---
 4 files changed, 83 insertions(+), 3 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index c435eaa772d5..35141155f368 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -127,6 +127,7 @@ struct dsa_switch {
 	 */
 	u32			dsa_port_mask;
 	u32			phys_port_mask;
+	u32			phys_mii_mask;
 	struct mii_bus		*slave_mii_bus;
 	struct net_device	*ports[DSA_MAX_PORTS];
 };
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 788b2b2f39f2..62f2f4e67d7d 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -144,6 +144,11 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index,
 		goto out;
 	}
 
+	/* Make the built-in MII bus mask match the number of ports,
+	 * switch drivers can override this later
+	 */
+	ds->phys_mii_mask = ds->phys_port_mask;
+
 	/*
 	 * If the CPU connects to this switch, set the switch tree
 	 * tagging protocol to the preferred tagging format of this
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index d4cf5cc747e3..a7f6f0c5fa31 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -33,6 +33,10 @@ struct dsa_slave_priv {
 	 * to this port.
 	 */
 	struct phy_device	*phy;
+	phy_interface_t		phy_interface;
+	int			old_link;
+	int			old_pause;
+	int			old_duplex;
 };
 
 /* dsa.c */
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 9e4d3816c54e..b4b6d457bfd0 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -12,6 +12,8 @@
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/phy.h>
+#include <linux/of_net.h>
+#include <linux/of_mdio.h>
 #include "dsa_priv.h"
 
 /* slave mii_bus handling ***************************************************/
@@ -19,7 +21,7 @@ static int dsa_slave_phy_read(struct mii_bus *bus, int addr, int reg)
 {
 	struct dsa_switch *ds = bus->priv;
 
-	if (ds->phys_port_mask & (1 << addr))
+	if (ds->phys_mii_mask & (1 << addr))
 		return ds->drv->phy_read(ds, addr, reg);
 
 	return 0xffff;
@@ -29,7 +31,7 @@ static int dsa_slave_phy_write(struct mii_bus *bus, int addr, int reg, u16 val)
 {
 	struct dsa_switch *ds = bus->priv;
 
-	if (ds->phys_port_mask & (1 << addr))
+	if (ds->phys_mii_mask & (1 << addr))
 		return ds->drv->phy_write(ds, addr, reg, val);
 
 	return 0;
@@ -330,7 +332,70 @@ static const struct net_device_ops trailer_netdev_ops = {
 };
 #endif
 
+static void dsa_slave_adjust_link(struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	unsigned int status_changed = 0;
+
+	if (p->old_link != p->phy->link) {
+		status_changed = 1;
+		p->old_link = p->phy->link;
+	}
+
+	if (p->old_duplex != p->phy->duplex) {
+		status_changed = 1;
+		p->old_duplex = p->phy->duplex;
+	}
+
+	if (p->old_pause != p->phy->pause) {
+		status_changed = 1;
+		p->old_pause = p->phy->pause;
+	}
+
+	if (status_changed)
+		phy_print_status(p->phy);
+}
+
 /* slave device setup *******************************************************/
+static void dsa_slave_phy_setup(struct dsa_slave_priv *p,
+				struct net_device *slave_dev)
+{
+	struct dsa_switch *ds = p->parent;
+	struct dsa_chip_data *cd = ds->pd;
+	struct device_node *phy_dn, *port_dn;
+	int ret;
+
+	port_dn = cd->port_dn[p->port];
+	p->phy_interface = of_get_phy_mode(port_dn);
+
+	phy_dn = of_parse_phandle(port_dn, "phy-handle", 0);
+	if (of_phy_is_fixed_link(port_dn)) {
+		/* In the case of a fixed PHY, the DT node associated
+		 * to the fixed PHY is the Port DT node
+		 */
+		ret = of_phy_register_fixed_link(port_dn);
+		if (ret) {
+			pr_err("failed to register fixed PHY\n");
+			return;
+		}
+		phy_dn = port_dn;
+	}
+
+	if (phy_dn)
+		p->phy = of_phy_connect(slave_dev, phy_dn,
+					dsa_slave_adjust_link, 0,
+					p->phy_interface);
+
+	/* We could not connect to a designated PHY, so use the switch internal
+	 * MDIO bus instead
+	 */
+	if (!p->phy)
+		p->phy = ds->slave_mii_bus->phy_map[p->port];
+	else
+		pr_info("attached PHY at address %d [%s]\n",
+			p->phy->addr, p->phy->drv->name);
+}
+
 struct net_device *
 dsa_slave_create(struct dsa_switch *ds, struct device *parent,
 		 int port, char *name)
@@ -378,7 +443,12 @@ dsa_slave_create(struct dsa_switch *ds, struct device *parent,
 	p->dev = slave_dev;
 	p->parent = ds;
 	p->port = port;
-	p->phy = ds->slave_mii_bus->phy_map[port];
+
+	p->old_pause = -1;
+	p->old_link = -1;
+	p->old_duplex = -1;
+
+	dsa_slave_phy_setup(p, slave_dev);
 
 	ret = register_netdev(slave_dev);
 	if (ret) {
-- 
1.9.1