[PATCH v3 net-next 3/4] net: dsa: microchip: get port link status

[<Tristram.Ha@microchip.com>]

From: Tristram Ha <Tristram.Ha@microchip.com>

Get port link status to know whether to read MIB counters when the link
is going down.  Add port_cleanup function to read MIB counters the last
time as when the port is disabled the PHY is also powered down.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
---
 drivers/net/dsa/microchip/ksz9477.c    |  2 ++
 drivers/net/dsa/microchip/ksz_common.c | 39 ++++++++++++++++++++++++++++++++--
 drivers/net/dsa/microchip/ksz_common.h |  3 +++
 drivers/net/dsa/microchip/ksz_priv.h   |  1 +
 4 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
index e2d74c7..6ad28e2 100644
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -1191,6 +1191,7 @@ static int ksz9477_setup(struct dsa_switch *ds)
 	.setup			= ksz9477_setup,
 	.phy_read		= ksz9477_phy_read16,
 	.phy_write		= ksz9477_phy_write16,
+	.adjust_link		= ksz_adjust_link,
 	.port_enable		= ksz_enable_port,
 	.port_disable		= ksz_disable_port,
 	.get_strings		= ksz9477_get_strings,
@@ -1340,6 +1341,7 @@ static void ksz9477_switch_exit(struct ksz_device *dev)
 	.cfg_port_member = ksz9477_cfg_port_member,
 	.flush_dyn_mac_table = ksz9477_flush_dyn_mac_table,
 	.phy_setup = ksz9477_phy_setup,
+	.port_cleanup = ksz_port_cleanup,
 	.port_setup = ksz9477_port_setup,
 	.r_mib_cnt = ksz9477_r_mib_cnt,
 	.r_mib_pkt = ksz9477_r_mib_pkt,
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index ff32ace..dd66056 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -20,6 +20,22 @@
 
 #include "ksz_priv.h"
 
+void ksz_port_cleanup(struct ksz_device *dev, int port)
+{
+	/* Read all MIB counters when the link is going down. */
+	if (dev->live_ports & (1 << port)) {
+		struct ksz_port *p = &dev->ports[port];
+
+		p->read = true;
+		schedule_work(&dev->mib_read);
+	}
+
+	/* Common code for port cleanup. */
+	dev->on_ports &= ~(1 << port);
+	dev->live_ports &= ~(1 << port);
+}
+EXPORT_SYMBOL_GPL(ksz_port_cleanup);
+
 void ksz_update_port_member(struct ksz_device *dev, int port)
 {
 	struct ksz_port *p;
@@ -156,6 +172,26 @@ int ksz_phy_write16(struct dsa_switch *ds, int addr, int reg, u16 val)
 }
 EXPORT_SYMBOL_GPL(ksz_phy_write16);
 
+void ksz_adjust_link(struct dsa_switch *ds, int port,
+		     struct phy_device *phydev)
+{
+	struct ksz_device *dev = ds->priv;
+	struct ksz_port *p = &dev->ports[port];
+
+	if (!phydev->link) {
+		/* Read all MIB counters when the link is going down. */
+		if (dev->live_ports & (1 << port)) {
+			p->read = true;
+			schedule_work(&dev->mib_read);
+		}
+		dev->live_ports &= ~(1 << port);
+	} else {
+		/* Remember which port is connected and active. */
+		dev->live_ports |= (1 << port) & dev->on_ports;
+	}
+}
+EXPORT_SYMBOL_GPL(ksz_adjust_link);
+
 int ksz_sset_count(struct dsa_switch *ds, int port, int sset)
 {
 	struct ksz_device *dev = ds->priv;
@@ -367,8 +403,7 @@ void ksz_disable_port(struct dsa_switch *ds, int port, struct phy_device *phy)
 {
 	struct ksz_device *dev = ds->priv;
 
-	dev->on_ports &= ~(1 << port);
-	dev->live_ports &= ~(1 << port);
+	dev->dev_ops->port_cleanup(dev, port);
 
 	/* port_stp_state_set() will be called after to disable the port so
 	 * there is no need to do anything.
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 0b0ed3d..ebe6f8e 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -7,6 +7,7 @@
 #ifndef __KSZ_COMMON_H
 #define __KSZ_COMMON_H
 
+void ksz_port_cleanup(struct ksz_device *dev, int port);
 void ksz_update_port_member(struct ksz_device *dev, int port);
 void ksz_init_mib_timer(struct ksz_device *dev);
 
@@ -14,6 +15,8 @@
 
 int ksz_phy_read16(struct dsa_switch *ds, int addr, int reg);
 int ksz_phy_write16(struct dsa_switch *ds, int addr, int reg, u16 val);
+void ksz_adjust_link(struct dsa_switch *ds, int port,
+		     struct phy_device *phydev);
 int ksz_sset_count(struct dsa_switch *ds, int port, int sset);
 void ksz_get_ethtool_stats(struct dsa_switch *ds, int port, uint64_t *buf);
 int ksz_port_bridge_join(struct dsa_switch *ds, int port,
diff --git a/drivers/net/dsa/microchip/ksz_priv.h b/drivers/net/dsa/microchip/ksz_priv.h
index 1d2d98f..a1d84c1 100644
--- a/drivers/net/dsa/microchip/ksz_priv.h
+++ b/drivers/net/dsa/microchip/ksz_priv.h
@@ -137,6 +137,7 @@ struct ksz_dev_ops {
 	void (*flush_dyn_mac_table)(struct ksz_device *dev, int port);
 	void (*phy_setup)(struct ksz_device *dev, int port,
 			  struct phy_device *phy);
+	void (*port_cleanup)(struct ksz_device *dev, int port);
 	void (*port_setup)(struct ksz_device *dev, int port, bool cpu_port);
 	void (*r_phy)(struct ksz_device *dev, u16 phy, u16 reg, u16 *val);
 	void (*w_phy)(struct ksz_device *dev, u16 phy, u16 reg, u16 val);
-- 
1.9.1