Fix R-Car I2C data byte sent twice issue

index aa3730d..c2498b45 100644
@@ -653,19 +653,23 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 		return PTR_ERR(priv->clk);
 	}
 
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->io = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->io))
+		return PTR_ERR(priv->io);
+
 	bus_speed = 100000; /* default 100 kHz */
 	of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
 
 	priv->devtype = (enum rcar_i2c_type)of_match_device(rcar_i2c_dt_ids, dev)->data;
 
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
 	ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
 	if (ret < 0)
-		return ret;
+		goto out_pm_put;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	priv->io = devm_ioremap_resource(dev, res);
-	if (IS_ERR(priv->io))
-		return PTR_ERR(priv->io);
+	pm_runtime_put(dev);
 
 	irq = platform_get_irq(pdev, 0);
 	init_waitqueue_head(&priv->wait);

@@ -685,22 +689,26 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 			       dev_name(dev), priv);
 	if (ret < 0) {
 		dev_err(dev, "cannot get irq %d\n", irq);
-		return ret;
+		goto out_pm_disable;
 	}
 
-	pm_runtime_enable(dev);
 	platform_set_drvdata(pdev, priv);
 
 	ret = i2c_add_numbered_adapter(adap);
 	if (ret < 0) {
 		dev_err(dev, "reg adap failed: %d\n", ret);
-		pm_runtime_disable(dev);
-		return ret;
+		goto out_pm_disable;
 	}
 
 	dev_info(dev, "probed\n");
 
 	return 0;
+
+ out_pm_put:
+	pm_runtime_put(dev);
+ out_pm_disable:
+	pm_runtime_disable(dev);
+	return ret;
 }
 
 static int rcar_i2c_remove(struct platform_device *pdev)

index c2498b45..fd76b15 100644
@@ -144,9 +144,10 @@ static void rcar_i2c_init(struct rcar_i2c_priv *priv)
 {
 	/* reset master mode */
 	rcar_i2c_write(priv, ICMIER, 0);
-	rcar_i2c_write(priv, ICMCR, 0);
+	rcar_i2c_write(priv, ICMCR, MDBS);
 	rcar_i2c_write(priv, ICMSR, 0);
-	rcar_i2c_write(priv, ICMAR, 0);
+	/* start clock */
+	rcar_i2c_write(priv, ICCCR, priv->icccr);
 }
 
 static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)

@@ -496,16 +497,6 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 
 	pm_runtime_get_sync(dev);
 
-	/*-------------- spin lock -----------------*/
-	spin_lock_irqsave(&priv->lock, flags);
-
-	rcar_i2c_init(priv);
-	/* start clock */
-	rcar_i2c_write(priv, ICCCR, priv->icccr);
-
-	spin_unlock_irqrestore(&priv->lock, flags);
-	/*-------------- spin unlock -----------------*/
-
 	ret = rcar_i2c_bus_barrier(priv);
 	if (ret < 0)
 		goto out;

@@ -669,6 +660,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto out_pm_put;
 
+	rcar_i2c_init(priv);
 	pm_runtime_put(dev);
 
 	irq = platform_get_irq(pdev, 0);

index fd76b15..30daad1 100644
@@ -94,7 +94,6 @@
 #define RCAR_IRQ_ACK_RECV	(~(MAT | MDR) & 0xFF)
 
 #define ID_LAST_MSG	(1 << 0)
-#define ID_IOERROR	(1 << 1)
 #define ID_DONE		(1 << 2)
 #define ID_ARBLOST	(1 << 3)
 #define ID_NACK		(1 << 4)

@@ -541,11 +540,6 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 			break;
 		}
 
-		if (rcar_i2c_flags_has(priv, ID_IOERROR)) {
-			ret = -EIO;
-			break;
-		}
-
 		ret = i + 1; /* The number of transfer */
 	}
 out:

index 30daad1..1c4566a 100644
@@ -33,7 +33,6 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
 
 /* register offsets */
 #define ICSCR	0x00	/* slave ctrl */

@@ -110,7 +109,6 @@ struct rcar_i2c_priv {
 	struct i2c_msg	*msg;
 	struct clk *clk;
 
-	spinlock_t lock;
 	wait_queue_head_t wait;
 
 	int pos;

@@ -429,9 +427,6 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
 	irqreturn_t result = IRQ_HANDLED;
 	u32 msr;
 
-	/*-------------- spin lock -----------------*/
-	spin_lock(&priv->lock);
-
 	if (rcar_i2c_slave_irq(priv))
 		goto exit;
 

@@ -478,9 +473,6 @@ out:
 	}
 
 exit:
-	spin_unlock(&priv->lock);
-	/*-------------- spin unlock -----------------*/
-
 	return result;
 }
 

@@ -490,9 +482,8 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 {
 	struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
 	struct device *dev = rcar_i2c_priv_to_dev(priv);
-	unsigned long flags;
 	int i, ret;
-	long timeout;
+	long time_left;
 
 	pm_runtime_get_sync(dev);
 

@@ -507,9 +498,6 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 			break;
 		}
 
-		/*-------------- spin lock -----------------*/
-		spin_lock_irqsave(&priv->lock, flags);
-
 		/* init each data */
 		priv->msg	= &msgs[i];
 		priv->pos	= 0;

@@ -519,13 +507,11 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 
 		rcar_i2c_prepare_msg(priv);
 
-		spin_unlock_irqrestore(&priv->lock, flags);
-		/*-------------- spin unlock -----------------*/
-
-		timeout = wait_event_timeout(priv->wait,
+		time_left = wait_event_timeout(priv->wait,
 					     rcar_i2c_flags_has(priv, ID_DONE),
 					     adap->timeout);
-		if (!timeout) {
+		if (!time_left) {
+			rcar_i2c_init(priv);
 			ret = -ETIMEDOUT;
 			break;
 		}

@@ -659,7 +645,6 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 
 	irq = platform_get_irq(pdev, 0);
 	init_waitqueue_head(&priv->wait);
-	spin_lock_init(&priv->lock);
 
 	adap = &priv->adap;
 	adap->nr = pdev->id;

index 1c4566a..c57ba96 100644
@@ -106,7 +106,8 @@ enum rcar_i2c_type {
 struct rcar_i2c_priv {
 	void __iomem *io;
 	struct i2c_adapter adap;
-	struct i2c_msg	*msg;
+	struct i2c_msg *msg;
+	int msgs_left;
 	struct clk *clk;
 
 	wait_queue_head_t wait;

@@ -255,6 +256,11 @@ static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
 {
 	int read = !!rcar_i2c_is_recv(priv);
 
+	priv->pos = 0;
+	priv->flags = 0;
+	if (priv->msgs_left == 1)
+		rcar_i2c_flags_set(priv, ID_LAST_MSG);
+
 	rcar_i2c_write(priv, ICMAR, (priv->msg->addr << 1) | read);
 	rcar_i2c_write(priv, ICMSR, 0);
 	rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);

@@ -499,11 +505,8 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 		}
 
 		/* init each data */
-		priv->msg	= &msgs[i];
-		priv->pos	= 0;
-		priv->flags	= 0;
-		if (i == num - 1)
-			rcar_i2c_flags_set(priv, ID_LAST_MSG);
+		priv->msg = &msgs[i];
+		priv->msgs_left = num - i;
 
 		rcar_i2c_prepare_msg(priv);
 

index c57ba96..37aa8a3 100644
@@ -267,10 +267,17 @@ static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
 	rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
 }
 
+static void rcar_i2c_next_msg(struct rcar_i2c_priv *priv)
+{
+	priv->msg++;
+	priv->msgs_left--;
+	rcar_i2c_prepare_msg(priv);
+}
+
 /*
  *		interrupt functions
  */
-static int rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
+static void rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
 {
 	struct i2c_msg *msg = priv->msg;
 

@@ -280,7 +287,7 @@ static int rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
 	 * Do nothing
 	 */
 	if (!(msr & MDE))
-		return 0;
+		return;
 
 	/*
 	 * If address transfer phase finished,

@@ -309,29 +316,23 @@ static int rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
 		 * [ICRXTX] -> [SHIFT] -> [I2C bus]
 		 */
 
-		if (priv->flags & ID_LAST_MSG)
+		if (priv->flags & ID_LAST_MSG) {
 			/*
 			 * If current msg is the _LAST_ msg,
 			 * prepare stop condition here.
 			 * ID_DONE will be set on STOP irq.
 			 */
 			rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
-		else
-			/*
-			 * If current msg is _NOT_ last msg,
-			 * it doesn't call stop phase.
-			 * thus, there is no STOP irq.
-			 * return ID_DONE here.
-			 */
-			return ID_DONE;
+		} else {
+			rcar_i2c_next_msg(priv);
+			return;
+		}
 	}
 
 	rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_SEND);
-
-	return 0;
 }
 
-static int rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
+static void rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
 {
 	struct i2c_msg *msg = priv->msg;
 

@@ -341,7 +342,7 @@ static int rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
 	 * Do nothing
 	 */
 	if (!(msr & MDR))
-		return 0;
+		return;
 
 	if (msr & MAT) {
 		/*

@@ -367,9 +368,10 @@ static int rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
 	else
 		rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
 
-	rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_RECV);
-
-	return 0;
+	if (priv->pos == msg->len && !(priv->flags & ID_LAST_MSG))
+		rcar_i2c_next_msg(priv);
+	else
+		rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_RECV);
 }
 
 static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)

@@ -462,14 +464,15 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
 
 	/* Stop */
 	if (msr & MST) {
+		priv->msgs_left--; /* The last message also made it */
 		rcar_i2c_flags_set(priv, ID_DONE);
 		goto out;
 	}
 
 	if (rcar_i2c_is_recv(priv))
-		rcar_i2c_flags_set(priv, rcar_i2c_irq_recv(priv, msr));
+		rcar_i2c_irq_recv(priv, msr);
 	else
-		rcar_i2c_flags_set(priv, rcar_i2c_irq_send(priv, msr));
+		rcar_i2c_irq_send(priv, msr);
 
 out:
 	if (rcar_i2c_flags_has(priv, ID_DONE)) {

@@ -501,35 +504,28 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 		/* This HW can't send STOP after address phase */
 		if (msgs[i].len == 0) {
 			ret = -EOPNOTSUPP;
-			break;
-		}
-
-		/* init each data */
-		priv->msg = &msgs[i];
-		priv->msgs_left = num - i;
-
-		rcar_i2c_prepare_msg(priv);
-
-		time_left = wait_event_timeout(priv->wait,
-					     rcar_i2c_flags_has(priv, ID_DONE),
-					     adap->timeout);
-		if (!time_left) {
-			rcar_i2c_init(priv);
-			ret = -ETIMEDOUT;
-			break;
-		}
-
-		if (rcar_i2c_flags_has(priv, ID_NACK)) {
-			ret = -ENXIO;
-			break;
-		}
-
-		if (rcar_i2c_flags_has(priv, ID_ARBLOST)) {
-			ret = -EAGAIN;
-			break;
+			goto out;
 		}
+	}
 
-		ret = i + 1; /* The number of transfer */
+	/* init data */
+	priv->msg = msgs;
+	priv->msgs_left = num;
+
+	rcar_i2c_prepare_msg(priv);
+
+	time_left = wait_event_timeout(priv->wait,
+				     rcar_i2c_flags_has(priv, ID_DONE),
+				     num * adap->timeout);
+	if (!time_left) {
+		rcar_i2c_init(priv);
+		ret = -ETIMEDOUT;
+	} else if (rcar_i2c_flags_has(priv, ID_NACK)) {
+		ret = -ENXIO;
+	} else if (rcar_i2c_flags_has(priv, ID_ARBLOST)) {
+		ret = -EAGAIN;
+	} else {
+		ret = num - priv->msgs_left; /* The number of transfer */
 	}
 out:
 	pm_runtime_put(dev);