net: dsa: bcm_sf2: add support for controlling EEE

When EEE is enabled, negotiate this feature with the PHY and make sure
that the capability checking, local EEE advertisement, link partner EEE
advertisement and auto-negotiation resolution returned by phy_init_eee()
is positive, and enable EEE at the switch level.

While querying the current EEE settings, verify the low-power indication
and indicate its status.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/bcm_sf2.c b/drivers/net/dsa/bcm_sf2.c
index 634e44e..b962596 100644
--- a/drivers/net/dsa/bcm_sf2.c
+++ b/drivers/net/dsa/bcm_sf2.c
@@ -220,6 +220,19 @@
 	core_writel(priv, reg, CORE_STS_OVERRIDE_IMP);
 }
 
+static void bcm_sf2_eee_enable_set(struct dsa_switch *ds, int port, bool enable)
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+	u32 reg;
+
+	reg = core_readl(priv, CORE_EEE_EN_CTRL);
+	if (enable)
+		reg |= 1 << port;
+	else
+		reg &= ~(1 << port);
+	core_writel(priv, reg, CORE_EEE_EN_CTRL);
+}
+
 static int bcm_sf2_port_setup(struct dsa_switch *ds, int port,
 			      struct phy_device *phy)
 {
@@ -247,6 +260,10 @@
 
 	bcm_sf2_imp_vlan_setup(ds, cpu_port);
 
+	/* If EEE was enabled, restore it */
+	if (priv->port_sts[port].eee.eee_enabled)
+		bcm_sf2_eee_enable_set(ds, port, true);
+
 	return 0;
 }
 
@@ -279,6 +296,60 @@
 	core_writel(priv, reg, CORE_MEM_PSM_VDD_CTRL);
 }
 
+/* Returns 0 if EEE was not enabled, or 1 otherwise
+ */
+static int bcm_sf2_eee_init(struct dsa_switch *ds, int port,
+			    struct phy_device *phy)
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+	struct ethtool_eee *p = &priv->port_sts[port].eee;
+	int ret;
+
+	p->supported = (SUPPORTED_1000baseT_Full | SUPPORTED_100baseT_Full);
+
+	ret = phy_init_eee(phy, 0);
+	if (ret)
+		return 0;
+
+	bcm_sf2_eee_enable_set(ds, port, true);
+
+	return 1;
+}
+
+static int bcm_sf2_sw_get_eee(struct dsa_switch *ds, int port,
+			      struct ethtool_eee *e)
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+	struct ethtool_eee *p = &priv->port_sts[port].eee;
+	u32 reg;
+
+	reg = core_readl(priv, CORE_EEE_LPI_INDICATE);
+	e->eee_enabled = p->eee_enabled;
+	e->eee_active = !!(reg & (1 << port));
+
+	return 0;
+}
+
+static int bcm_sf2_sw_set_eee(struct dsa_switch *ds, int port,
+			      struct phy_device *phydev,
+			      struct ethtool_eee *e)
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+	struct ethtool_eee *p = &priv->port_sts[port].eee;
+
+	p->eee_enabled = e->eee_enabled;
+
+	if (!p->eee_enabled) {
+		bcm_sf2_eee_enable_set(ds, port, false);
+	} else {
+		p->eee_enabled = bcm_sf2_eee_init(ds, port, phydev);
+		if (!p->eee_enabled)
+			return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
 static irqreturn_t bcm_sf2_switch_0_isr(int irq, void *dev_id)
 {
 	struct bcm_sf2_priv *priv = dev_id;
@@ -792,6 +863,8 @@
 	.set_wol		= bcm_sf2_sw_set_wol,
 	.port_enable		= bcm_sf2_port_setup,
 	.port_disable		= bcm_sf2_port_disable,
+	.get_eee		= bcm_sf2_sw_get_eee,
+	.set_eee		= bcm_sf2_sw_set_eee,
 };
 
 static int __init bcm_sf2_init(void)