net: dsa: mt7530: add interrupt support

Add support for MT7530 interrupt controller to handle internal PHYs.
In order to assign an IRQ number to each PHY, the registration of MDIO bus
is also done in this driver.

Signed-off-by: DENG Qingfang <dqfext@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 238 insertions, 26 deletions

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 96f7c9eede35..db838343fb05 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -10,6 +10,7 @@
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
+#include <linux/of_irq.h>
 #include <linux/of_mdio.h>
 #include <linux/of_net.h>
 #include <linux/of_platform.h>
@@ -596,18 +597,14 @@ mt7530_mib_reset(struct dsa_switch *ds)
 	mt7530_write(priv, MT7530_MIB_CCR, CCR_MIB_ACTIVATE);
 }
 
-static int mt7530_phy_read(struct dsa_switch *ds, int port, int regnum)
+static int mt7530_phy_read(struct mt7530_priv *priv, int port, int regnum)
 {
-	struct mt7530_priv *priv = ds->priv;
-
 	return mdiobus_read_nested(priv->bus, port, regnum);
 }
 
-static int mt7530_phy_write(struct dsa_switch *ds, int port, int regnum,
+static int mt7530_phy_write(struct mt7530_priv *priv, int port, int regnum,
 			    u16 val)
 {
-	struct mt7530_priv *priv = ds->priv;
-
 	return mdiobus_write_nested(priv->bus, port, regnum, val);
 }
 
@@ -785,9 +782,8 @@ out:
 }
 
 static int
-mt7531_ind_phy_read(struct dsa_switch *ds, int port, int regnum)
+mt7531_ind_phy_read(struct mt7530_priv *priv, int port, int regnum)
 {
-	struct mt7530_priv *priv = ds->priv;
 	int devad;
 	int ret;
 
@@ -803,10 +799,9 @@ mt7531_ind_phy_read(struct dsa_switch *ds, int port, int regnum)
 }
 
 static int
-mt7531_ind_phy_write(struct dsa_switch *ds, int port, int regnum,
+mt7531_ind_phy_write(struct mt7530_priv *priv, int port, int regnum,
 		     u16 data)
 {
-	struct mt7530_priv *priv = ds->priv;
 	int devad;
 	int ret;
 
@@ -822,6 +817,22 @@ mt7531_ind_phy_write(struct dsa_switch *ds, int port, int regnum,
 	return ret;
 }
 
+static int
+mt753x_phy_read(struct mii_bus *bus, int port, int regnum)
+{
+	struct mt7530_priv *priv = bus->priv;
+
+	return priv->info->phy_read(priv, port, regnum);
+}
+
+static int
+mt753x_phy_write(struct mii_bus *bus, int port, int regnum, u16 val)
+{
+	struct mt7530_priv *priv = bus->priv;
+
+	return priv->info->phy_write(priv, port, regnum, val);
+}
+
 static void
 mt7530_get_strings(struct dsa_switch *ds, int port, u32 stringset,
 		   uint8_t *data)
@@ -1828,6 +1839,210 @@ mt7530_setup_gpio(struct mt7530_priv *priv)
 }
 #endif /* CONFIG_GPIOLIB */
 
+static irqreturn_t
+mt7530_irq_thread_fn(int irq, void *dev_id)
+{
+	struct mt7530_priv *priv = dev_id;
+	bool handled = false;
+	u32 val;
+	int p;
+
+	mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
+	val = mt7530_mii_read(priv, MT7530_SYS_INT_STS);
+	mt7530_mii_write(priv, MT7530_SYS_INT_STS, val);
+	mutex_unlock(&priv->bus->mdio_lock);
+
+	for (p = 0; p < MT7530_NUM_PHYS; p++) {
+		if (BIT(p) & val) {
+			unsigned int irq;
+
+			irq = irq_find_mapping(priv->irq_domain, p);
+			handle_nested_irq(irq);
+			handled = true;
+		}
+	}
+
+	return IRQ_RETVAL(handled);
+}
+
+static void
+mt7530_irq_mask(struct irq_data *d)
+{
+	struct mt7530_priv *priv = irq_data_get_irq_chip_data(d);
+
+	priv->irq_enable &= ~BIT(d->hwirq);
+}
+
+static void
+mt7530_irq_unmask(struct irq_data *d)
+{
+	struct mt7530_priv *priv = irq_data_get_irq_chip_data(d);
+
+	priv->irq_enable |= BIT(d->hwirq);
+}
+
+static void
+mt7530_irq_bus_lock(struct irq_data *d)
+{
+	struct mt7530_priv *priv = irq_data_get_irq_chip_data(d);
+
+	mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
+}
+
+static void
+mt7530_irq_bus_sync_unlock(struct irq_data *d)
+{
+	struct mt7530_priv *priv = irq_data_get_irq_chip_data(d);
+
+	mt7530_mii_write(priv, MT7530_SYS_INT_EN, priv->irq_enable);
+	mutex_unlock(&priv->bus->mdio_lock);
+}
+
+static struct irq_chip mt7530_irq_chip = {
+	.name = KBUILD_MODNAME,
+	.irq_mask = mt7530_irq_mask,
+	.irq_unmask = mt7530_irq_unmask,
+	.irq_bus_lock = mt7530_irq_bus_lock,
+	.irq_bus_sync_unlock = mt7530_irq_bus_sync_unlock,
+};
+
+static int
+mt7530_irq_map(struct irq_domain *domain, unsigned int irq,
+	       irq_hw_number_t hwirq)
+{
+	irq_set_chip_data(irq, domain->host_data);
+	irq_set_chip_and_handler(irq, &mt7530_irq_chip, handle_simple_irq);
+	irq_set_nested_thread(irq, true);
+	irq_set_noprobe(irq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops mt7530_irq_domain_ops = {
+	.map = mt7530_irq_map,
+	.xlate = irq_domain_xlate_onecell,
+};
+
+static void
+mt7530_setup_mdio_irq(struct mt7530_priv *priv)
+{
+	struct dsa_switch *ds = priv->ds;
+	int p;
+
+	for (p = 0; p < MT7530_NUM_PHYS; p++) {
+		if (BIT(p) & ds->phys_mii_mask) {
+			unsigned int irq;
+
+			irq = irq_create_mapping(priv->irq_domain, p);
+			ds->slave_mii_bus->irq[p] = irq;
+		}
+	}
+}
+
+static int
+mt7530_setup_irq(struct mt7530_priv *priv)
+{
+	struct device *dev = priv->dev;
+	struct device_node *np = dev->of_node;
+	int ret;
+
+	if (!of_property_read_bool(np, "interrupt-controller")) {
+		dev_info(dev, "no interrupt support\n");
+		return 0;
+	}
+
+	priv->irq = of_irq_get(np, 0);
+	if (priv->irq <= 0) {
+		dev_err(dev, "failed to get parent IRQ: %d\n", priv->irq);
+		return priv->irq ? : -EINVAL;
+	}
+
+	priv->irq_domain = irq_domain_add_linear(np, MT7530_NUM_PHYS,
+						 &mt7530_irq_domain_ops, priv);
+	if (!priv->irq_domain) {
+		dev_err(dev, "failed to create IRQ domain\n");
+		return -ENOMEM;
+	}
+
+	/* This register must be set for MT7530 to properly fire interrupts */
+	if (priv->id != ID_MT7531)
+		mt7530_set(priv, MT7530_TOP_SIG_CTRL, TOP_SIG_CTRL_NORMAL);
+
+	ret = request_threaded_irq(priv->irq, NULL, mt7530_irq_thread_fn,
+				   IRQF_ONESHOT, KBUILD_MODNAME, priv);
+	if (ret) {
+		irq_domain_remove(priv->irq_domain);
+		dev_err(dev, "failed to request IRQ: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void
+mt7530_free_mdio_irq(struct mt7530_priv *priv)
+{
+	int p;
+
+	for (p = 0; p < MT7530_NUM_PHYS; p++) {
+		if (BIT(p) & priv->ds->phys_mii_mask) {
+			unsigned int irq;
+
+			irq = irq_find_mapping(priv->irq_domain, p);
+			irq_dispose_mapping(irq);
+		}
+	}
+}
+
+static void
+mt7530_free_irq_common(struct mt7530_priv *priv)
+{
+	free_irq(priv->irq, priv);
+	irq_domain_remove(priv->irq_domain);
+}
+
+static void
+mt7530_free_irq(struct mt7530_priv *priv)
+{
+	mt7530_free_mdio_irq(priv);
+	mt7530_free_irq_common(priv);
+}
+
+static int
+mt7530_setup_mdio(struct mt7530_priv *priv)
+{
+	struct dsa_switch *ds = priv->ds;
+	struct device *dev = priv->dev;
+	struct mii_bus *bus;
+	static int idx;
+	int ret;
+
+	bus = devm_mdiobus_alloc(dev);
+	if (!bus)
+		return -ENOMEM;
+
+	ds->slave_mii_bus = bus;
+	bus->priv = priv;
+	bus->name = KBUILD_MODNAME "-mii";
+	snprintf(bus->id, MII_BUS_ID_SIZE, KBUILD_MODNAME "-%d", idx++);
+	bus->read = mt753x_phy_read;
+	bus->write = mt753x_phy_write;
+	bus->parent = dev;
+	bus->phy_mask = ~ds->phys_mii_mask;
+
+	if (priv->irq)
+		mt7530_setup_mdio_irq(priv);
+
+	ret = mdiobus_register(bus);
+	if (ret) {
+		dev_err(dev, "failed to register MDIO bus: %d\n", ret);
+		if (priv->irq)
+			mt7530_free_mdio_irq(priv);
+	}
+
+	return ret;
+}
+
 static int
 mt7530_setup(struct dsa_switch *ds)
 {
@@ -2791,24 +3006,20 @@ static int
 mt753x_setup(struct dsa_switch *ds)
 {
 	struct mt7530_priv *priv = ds->priv;
+	int ret = priv->info->sw_setup(ds);
 
-	return priv->info->sw_setup(ds);
-}
-
-static int
-mt753x_phy_read(struct dsa_switch *ds, int port, int regnum)
-{
-	struct mt7530_priv *priv = ds->priv;
+	if (ret)
+		return ret;
 
-	return priv->info->phy_read(ds, port, regnum);
-}
+	ret = mt7530_setup_irq(priv);
+	if (ret)
+		return ret;
 
-static int
-mt753x_phy_write(struct dsa_switch *ds, int port, int regnum, u16 val)
-{
-	struct mt7530_priv *priv = ds->priv;
+	ret = mt7530_setup_mdio(priv);
+	if (ret && priv->irq)
+		mt7530_free_irq_common(priv);
 
-	return priv->info->phy_write(ds, port, regnum, val);
+	return ret;
 }
 
 static int mt753x_get_mac_eee(struct dsa_switch *ds, int port,
@@ -2845,8 +3056,6 @@ static const struct dsa_switch_ops mt7530_switch_ops = {
 	.get_tag_protocol	= mtk_get_tag_protocol,
 	.setup			= mt753x_setup,
 	.get_strings		= mt7530_get_strings,
-	.phy_read		= mt753x_phy_read,
-	.phy_write		= mt753x_phy_write,
 	.get_ethtool_stats	= mt7530_get_ethtool_stats,
 	.get_sset_count		= mt7530_get_sset_count,
 	.set_ageing_time	= mt7530_set_ageing_time,
@@ -3029,6 +3238,9 @@ mt7530_remove(struct mdio_device *mdiodev)
 		dev_err(priv->dev, "Failed to disable io pwr: %d\n",
 			ret);
 
+	if (priv->irq)
+		mt7530_free_irq(priv);
+
 	dsa_unregister_switch(priv->ds);
 	mutex_destroy(&priv->reg_mutex);
 }