Add FSI interrupt support for hub

index 3d382e6..36dde94 100644
@@ -778,22 +778,32 @@ static void fsi_master_unscan(struct fsi_master *master)
 	master->slave_list = false;
 }
 
-static void fsi_master_irq(struct fsi_master *master, int link, uint32_t si1s)
+static int __fsi_dev_irq(struct device *dev, void *data)
 {
-	struct fsi_slave *slave;
-	struct fsi_device *fsi_dev;
-
-	if (list_empty(&master->my_slaves))
-		return;
+	uint32_t *si1s = data;
+	struct fsi_device *fsi_dev = to_fsi_dev(dev);
 
-	slave = list_first_entry(&master->my_slaves, struct fsi_slave,
-				list_link);
+	if (!fsi_dev || !si1s) {
+		dev_dbg(dev, "Invalid input: %p %p\n", fsi_dev, si1s);
+		return -EINVAL;
+	}
 
-	list_for_each_entry(fsi_dev, &slave->my_engines, link) {
-		if (si1s & (0x80000000 >> fsi_dev->si1s_bit) &&
-		    fsi_dev->irq_handler)
-			fsi_dev->irq_handler(0, &fsi_dev->dev);
+	if (*si1s & (0x80000000 >> fsi_dev->si1s_bit) && fsi_dev->irq_handler) {
+		fsi_dev->irq_handler(0, &fsi_dev->dev);
+		return 1;
 	}
+
+	return 0;
+}
+
+static int __fsi_slave_irq(struct device *dev, void *data)
+{
+	return device_for_each_child(dev, data, __fsi_dev_irq);
+}
+
+static void fsi_master_irq(struct fsi_master *master, int link, uint32_t si1s)
+{
+	device_for_each_child(master->dev, &si1s, __fsi_slave_irq);
 }
 
 static int fsi_master_ipoll(void *data)

index 36dde94..45e1171 100644
@@ -98,6 +98,11 @@ static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
 #define FSI_SI1S		0x1C	/* R: IRQ status */
 
 /*
+ * SI1S, SI1M fields
+ */
+#define FSI_SI1_HUB_SRC		0x00100000	/* hub IRQ source */
+
+/*
  * SMODE fields
  */
 #define	FSI_SMODE_WSC		0x80000000	/* Warm start done */

@@ -793,6 +798,13 @@ static int __fsi_dev_irq(struct device *dev, void *data)
 		return 1;
 	}
 
+	if (!(*si1s & FSI_SI1_HUB_SRC)) {
+		dev_dbg(dev, "IRQ not from a hub source\n");
+		return 0;
+	}
+
+	/* TODO: handle hub sourced IRQ */
+
 	return 0;
 }
 

index 45e1171..72f3a35 100644
@@ -96,6 +96,10 @@ static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
 #define	FSI_SMODE		0x0	/* R/W: Mode register */
 #define FSI_SI1M		0x18	/* R/W: IRQ mask */
 #define FSI_SI1S		0x1C	/* R: IRQ status */
+#define FSI_SRSIC0		0x68	/* R/W: Remote IRQ condition 0 */
+#define FSI_SRSIC1		0x6C	/* R/W: Remote IRQ condition 1 */
+#define FSI_SRSIM0		0x70	/* R/W: Remote IRQ mask 0 */
+#define FSI_SRSIS0		0x78	/* R: Remote IRQ status 0 */
 
 /*
  * SI1S, SI1M fields

@@ -116,6 +120,13 @@ static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
 #define	FSI_SMODE_LBCRR_SHIFT	8		/* Clk ratio shift */
 #define	FSI_SMODE_LBCRR_MASK	0xf		/* Clk ratio mask */
 
+/*
+ * SRSIS, SRSIM, SRSIC fields
+ */
+#define	FSI_SRSIX_IRQ1_MASK	0x00aaaaaa	/* SI1 IRQ sources */
+#define	FSI_SRSIX_BITS_PER_LINK	8
+
+
 /* FSI endpoint-device support */
 int fsi_device_read(struct fsi_device *dev, uint32_t addr, void *val,
 		size_t size)

@@ -584,6 +595,21 @@ static struct bin_attribute fsi_slave_raw_attr = {
 	.write = fsi_slave_sysfs_raw_write,
 };
 
+static int fsi_slave_irq_clear(struct fsi_slave *slave)
+{
+	uint32_t clear = ~0;
+	int rc;
+
+	rc = fsi_slave_write(slave, FSI_SLAVE_BASE + FSI_SRSIC0, &clear,
+				sizeof(clear));
+	if (rc) {
+		dev_dbg(&slave->dev, "Failed on write to SRSIC0\n");
+		return rc;
+	}
+	return fsi_slave_write(slave, FSI_SLAVE_BASE + FSI_SRSIC1, &clear,
+				sizeof(clear));
+}
+
 static int fsi_slave_init(struct fsi_master *master,
 		int link, uint8_t slave_id)
 {

@@ -649,8 +675,11 @@ static int fsi_slave_init(struct fsi_master *master,
 		dev_warn(&slave->dev, "failed to create raw attr: %d\n", rc);
 
 	list_add(&slave->list_link, &master->my_slaves);
-	fsi_slave_scan(slave);
-	return 0;
+	rc = fsi_slave_scan(slave);
+	if (rc)
+		return rc;
+
+	return fsi_slave_irq_clear(slave);
 }
 
 /* FSI master support */

@@ -783,10 +812,62 @@ static void fsi_master_unscan(struct fsi_master *master)
 	master->slave_list = false;
 }
 
+/* TODO: Add support for hub links 4-7 */
+static int next_hublink_source(struct fsi_slave *slave, uint32_t srsis)
+{
+	int index;
+
+	if (!slave)
+		return -EINVAL;
+
+	if (!(srsis & FSI_SRSIX_IRQ1_MASK)) {
+		dev_dbg(&slave->dev, "Unexpected IRQ source SRSIS:0x%08x\n",
+			srsis);
+		return -EINVAL;
+	}
+
+	/*
+	 * TODO: add a fair scheduler to ensure we don't favor lower
+	 * hublink IRQ sources over others
+	 */
+	index = __clz(srsis);
+	dev_dbg(&slave->dev, "SRSIS:0x%08x index:%d\n", srsis, index);
+	return index / FSI_SRSIX_BITS_PER_LINK;
+}
+
+static int __fsi_dev_irq(struct device *dev, void *data);
+
+static int __fsi_hub_slave_irq(struct device *dev, void *data)
+{
+	int rc;
+	struct fsi_slave *hub_slave = to_fsi_slave(dev);
+	uint32_t si1s;
+
+	if (!hub_slave) {
+		dev_dbg(dev, "Could not find hub slave\n");
+		return -ENODEV;
+	}
+
+	rc = fsi_slave_read(hub_slave, FSI_SLAVE_BASE + FSI_SI1S, &si1s,
+			sizeof(si1s));
+	if (rc) {
+		dev_dbg(dev, "Fail on read of hub slave si1s\n");
+		return rc;
+	}
+
+	if (!si1s)
+		return 0;
+
+	return device_for_each_child(dev, &si1s, __fsi_dev_irq);
+}
+
 static int __fsi_dev_irq(struct device *dev, void *data)
 {
-	uint32_t *si1s = data;
+	uint32_t *si1s = data, srsis;
 	struct fsi_device *fsi_dev = to_fsi_dev(dev);
+	struct fsi_slave *slave;
+	struct fsi_master_hub *hub;
+	int rc, hublink;
 
 	if (!fsi_dev || !si1s) {
 		dev_dbg(dev, "Invalid input: %p %p\n", fsi_dev, si1s);

@@ -803,9 +884,47 @@ static int __fsi_dev_irq(struct device *dev, void *data)
 		return 0;
 	}
 
-	/* TODO: handle hub sourced IRQ */
+	hub = dev_get_drvdata(dev);
+	if (!hub) {
+		dev_dbg(dev, "Not a hub device\n");
+		return 0;
+	}
 
-	return 0;
+	/* Scan the hub links for the source of IRQ */
+	slave = to_fsi_slave(dev->parent);
+	if (!slave) {
+		dev_dbg(dev, "Could not retrieve device's slave\n");
+		return -ENODEV;
+	}
+
+	rc = fsi_slave_read(slave, FSI_SLAVE_BASE + FSI_SRSIS0, &srsis,
+			sizeof(srsis));
+	if (rc) {
+		dev_dbg(&slave->dev, "Failed to read SRSIS0\n");
+		return rc;
+	}
+	if (srsis) {
+		hublink = next_hublink_source(slave, srsis);
+
+		if (!hub->master.dev)
+			return 0;
+
+		device_for_each_child(dev, &hublink, __fsi_hub_slave_irq);
+
+		/* Clear out the interrupting condition */
+		srsis = 0xff000000 >> (hublink * FSI_SRSIX_BITS_PER_LINK);
+		rc =  fsi_slave_write(slave, FSI_SLAVE_BASE + FSI_SRSIC0,
+					&srsis, sizeof(srsis));
+		if (rc) {
+			dev_dbg(&slave->dev, "Failed to clear out SRSIC\n");
+			return rc;
+		}
+	} else {
+		dev_dbg(&slave->dev, "SI1S HUB src but no SRSIS0 bits!\n");
+		return -EINVAL;
+	}
+
+	return 1;
 }
 
 static int __fsi_slave_irq(struct device *dev, void *data)

index 72f3a35..9f55d69 100644
@@ -1086,17 +1086,140 @@ void fsi_driver_unregister(struct fsi_driver *fsi_drv)
 }
 EXPORT_SYMBOL_GPL(fsi_driver_unregister);
 
+static uint32_t link_to_srsim_mask(int link)
+{
+	return ((0x80000000 >> 6) >> FSI_SRSIX_BITS_PER_LINK*link);
+}
+
+static uint32_t link_to_msiep_mask(int link)
+{
+	return (0xf0000000 >> (FSI_MSIEP_BITS_PER_LINK*link));
+}
+
+static int set_si1m(struct fsi_slave *slave, uint32_t mask, int on)
+{
+	int rc;
+	uint32_t si1m;
+
+	rc = fsi_slave_read(slave, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+			sizeof(si1m));
+	if (rc) {
+		dev_dbg(&slave->dev, "Failed to read SI1M\n");
+		return rc;
+	}
+
+	if (on)
+		si1m |= mask;
+	else
+		si1m &= ~mask;
+
+	return fsi_slave_write(slave, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+			sizeof(si1m));
+}
+
+static int set_upstream_irq_masks(struct fsi_master *master,
+				struct fsi_slave *slave, int on)
+{
+	struct fsi_slave *upstream_slave;
+	struct fsi_master *upstream_master;
+	uint32_t mask, si1m;
+	int rc;
+
+	if (!master->idx)
+		return 0;
+
+	upstream_slave = to_fsi_slave(slave->master->dev->parent);
+	if (!upstream_slave) {
+		dev_dbg(&slave->dev, "No upstream slave found\n");
+		return -ENODEV;
+	}
+
+	rc = fsi_slave_read(upstream_slave, FSI_SLAVE_BASE + FSI_SRSIM0, &si1m,
+			sizeof(si1m));
+	if (rc) {
+		dev_dbg(&slave->dev, "Failed to read SRSIM0\n");
+		return rc;
+	}
+
+	mask = link_to_srsim_mask(slave->link);
+	if (on)
+		si1m |= mask;
+	else
+		si1m &= ~mask;
+	rc = fsi_slave_write(upstream_slave, FSI_SLAVE_BASE + FSI_SRSIM0, &si1m,
+			sizeof(si1m));
+	if (rc) {
+		dev_dbg(&slave->dev, "Failed to write SRSIM0\n");
+		return rc;
+	}
+
+	upstream_master = upstream_slave->master;
+	if (!upstream_master) {
+		dev_dbg(&upstream_slave->dev, "Cannot find master\n");
+		return -ENODEV;
+	}
+
+	rc = upstream_master->read(upstream_master, 0, 0,
+				FSI_HUB_CONTROL + FSI_MSIEP0, &si1m,
+				sizeof(si1m));
+	if (rc) {
+		dev_dbg(&upstream_slave->dev,
+			"Could not read master's MSIEP\n");
+		return rc;
+	}
+
+	/* TODO: merge this into above on/off check */
+	mask = link_to_msiep_mask(slave->link);
+	if (on) {
+		upstream_master->ipoll |= FSI_SI1_HUB_SRC;
+		si1m |= mask;
+	} else {
+		upstream_master->ipoll &= ~FSI_SI1_HUB_SRC;
+		si1m &= ~mask;
+	}
+
+	rc = upstream_master->write(upstream_master, 0, 0,
+				FSI_HUB_CONTROL + FSI_MSIEP0, &si1m,
+				sizeof(si1m));
+	if (rc) {
+		dev_dbg(&upstream_slave->dev,
+			"Failed to write to master's MSIEP\n");
+		return rc;
+	}
+	si1m = 0xd0040410;
+	rc = upstream_master->write(upstream_master, 0, 0,
+				FSI_HUB_CONTROL + FSI_MMODE, &si1m,
+				sizeof(si1m));
+	if (rc) {
+		dev_dbg(&upstream_slave->dev,
+			"Failed to set hub I POLL\n");
+	}
+
+	si1m = FSI_SI1_HUB_SRC;
+	rc = upstream_master->write(upstream_master, 0, 0,
+				FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+				sizeof(si1m));
+	if (rc) {
+		dev_dbg(&upstream_slave->dev,
+			"Failed to set hub mask in SI1M\n");
+	}
+
+	return set_si1m(upstream_slave, FSI_SI1_HUB_SRC, on);
+}
+
 int fsi_enable_irq(struct fsi_device *dev)
 {
 	int rc;
 	u32 si1m;
 	u32 bit = 0x80000000 >> dev->si1s_bit;
 	struct fsi_master *master = dev->slave->master;
+	struct fsi_slave *slave = dev->slave;
+	int link = slave->link;
 
 	if (!dev->irq_handler)
 		return -EINVAL;
 
-	rc = master->read(master, 0, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+	rc = master->read(master, link, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
 			sizeof(u32));
 	if (rc) {
 		dev_err(master->dev, "couldn't read si1m:%d\n", rc);

@@ -1104,7 +1227,7 @@ int fsi_enable_irq(struct fsi_device *dev)
 	}
 
 	si1m |= bit;
-	rc = master->write(master, 0, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+	rc = master->write(master, link, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
 			sizeof(u32));
 	if (rc) {
 		dev_err(master->dev, "couldn't write si1m:%d\n", rc);

@@ -1112,7 +1235,7 @@ int fsi_enable_irq(struct fsi_device *dev)
 	}
 
 	master->ipoll |= bit;
-	return 0;
+	return set_upstream_irq_masks(master, slave, 1);
 }
 EXPORT_SYMBOL_GPL(fsi_enable_irq);
 

@@ -1122,10 +1245,12 @@ void fsi_disable_irq(struct fsi_device *dev)
 	u32 si1m;
 	u32 bits = ~(0x80000000 >> dev->si1s_bit);
 	struct fsi_master *master = dev->slave->master;
+	struct fsi_slave *slave = dev->slave;
+	int link = dev->slave->link;
 
 	master->ipoll &= bits;
 
-	rc = master->read(master, 0, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+	rc = master->read(master, link, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
 			sizeof(u32));
 	if (rc) {
 		dev_err(master->dev, "couldn't read si1m:%d\n", rc);

@@ -1133,12 +1258,15 @@ void fsi_disable_irq(struct fsi_device *dev)
 	}
 
 	si1m &= bits;
-	rc = master->write(master, 0, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
+	rc = master->write(master, link, 0, FSI_SLAVE_BASE + FSI_SI1M, &si1m,
 			sizeof(u32));
 	if (rc) {
 		dev_err(master->dev, "couldn't write si1m:%d\n", rc);
 		return;
 	}
+
+	if (!master->ipoll)
+		set_upstream_irq_masks(master, slave, 0);
 }
 
 struct bus_type fsi_bus_type = {

index 54723a7..7c9c3fa 100644
@@ -27,6 +27,7 @@
 #define FSI_MLEVP0		0x18		/* R: plug detect */
 #define FSI_MSENP0		0x18		/* S: Set enable */
 #define FSI_MCENP0		0x20		/* C: Clear enable */
+#define FSI_MSIEP0		0x30		/* R/W: Slave IRQ enable */
 #define FSI_MAEB		0x70		/* R: Error address */
 #define FSI_MVER		0x74		/* R: master version/type */
 #define FSI_MRESP0		0xd0		/* W: Port reset */

@@ -47,6 +48,9 @@
 #define FSI_MMODE_CRS1SHFT	8		/* Clk rate selection 1 shift */
 #define FSI_MMODE_CRS1MASK	0x3ff		/* Clk rate selection 1 mask */
 
+/* MSIEP: Slave interrupt enable */
+#define FSI_MSIEP_BITS_PER_LINK	4
+
 /* MRESB: Reset brindge */
 #define FSI_MRESB_RST_GEN	0x80000000	/* General reset */
 #define FSI_MRESB_RST_ERR	0x40000000	/* Error Reset */