5 files changed, 91 insertions, 70 deletions

diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c
index 8abfa4a03ce..ce1a32b71e4 100644
--- a/drivers/i2c/busses/i2c-eg20t.c
+++ b/drivers/i2c/busses/i2c-eg20t.c
@@ -673,32 +673,33 @@ static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap,
 	/* transfer not completed */
 	adap->pch_i2c_xfer_in_progress = true;
 
-	pmsg = &msgs[0];
-	pmsg->flags |= adap->pch_buff_mode_en;
-	status = pmsg->flags;
-	pch_dbg(adap,
-		"After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
-	/* calculate sub address length and message length */
-	/* these are applicable only for buffer mode */
-	subaddrlen = pmsg->buf[0];
-	/* calculate actual message length excluding
-	 * the sub address fields */
-	msglen = (pmsg->len) - (subaddrlen + 1);
-	if (status & (I2C_M_RD)) {
-		pch_dbg(adap, "invoking pch_i2c_readbytes\n");
-		ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
-				   (i == 0));
-	} else {
-		pch_dbg(adap, "invoking pch_i2c_writebytes\n");
-		ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num),
-				    (i == 0));
+	for (i = 0; i < num && ret >= 0; i++) {
+		pmsg = &msgs[i];
+		pmsg->flags |= adap->pch_buff_mode_en;
+		status = pmsg->flags;
+		pch_dbg(adap,
+			"After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
+		/* calculate sub address length and message length */
+		/* these are applicable only for buffer mode */
+		subaddrlen = pmsg->buf[0];
+		/* calculate actual message length excluding
+		 * the sub address fields */
+		msglen = (pmsg->len) - (subaddrlen + 1);
+
+		if ((status & (I2C_M_RD)) != false) {
+			ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
+						(i == 0));
+		} else {
+			ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num),
+						 (i == 0));
+		}
 	}
 
 	adap->pch_i2c_xfer_in_progress = false;	/* transfer completed */
 
 	mutex_unlock(&pch_mutex);
 
-	return ret;
+	return (ret < 0) ? ret : num;
 }
 
 /**
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 0c731ca69f1..b228e09c5d0 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -146,6 +146,7 @@ struct i2c_nmk_client {
  * @stop: stop condition
  * @xfer_complete: acknowledge completion for a I2C message
  * @result: controller propogated result
+ * @regulator: pointer to i2c regulator
  * @busy: Busy doing transfer
  */
 struct nmk_i2c_dev {
@@ -417,12 +418,12 @@ static int read_i2c(struct nmk_i2c_dev *dev)
 	writel(readl(dev->virtbase + I2C_IMSCR) | irq_mask,
 			dev->virtbase + I2C_IMSCR);
 
-	timeout = wait_for_completion_interruptible_timeout(
+	timeout = wait_for_completion_timeout(
 		&dev->xfer_complete, dev->adap.timeout);
 
 	if (timeout < 0) {
 		dev_err(&dev->pdev->dev,
-			"wait_for_completion_interruptible_timeout"
+			"wait_for_completion_timeout"
 			"returned %d waiting for event\n", timeout);
 		status = timeout;
 	}
@@ -504,12 +505,12 @@ static int write_i2c(struct nmk_i2c_dev *dev)
 	writel(readl(dev->virtbase + I2C_IMSCR) | irq_mask,
 			dev->virtbase + I2C_IMSCR);
 
-	timeout = wait_for_completion_interruptible_timeout(
+	timeout = wait_for_completion_timeout(
 		&dev->xfer_complete, dev->adap.timeout);
 
 	if (timeout < 0) {
 		dev_err(&dev->pdev->dev,
-			"wait_for_completion_interruptible_timeout"
+			"wait_for_completion_timeout "
 			"returned %d waiting for event\n", timeout);
 		status = timeout;
 	}
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 1a766cf74f6..2dfb6317685 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1139,41 +1139,12 @@ omap_i2c_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_SUSPEND
-static int omap_i2c_suspend(struct device *dev)
-{
-	if (!pm_runtime_suspended(dev))
-		if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_suspend)
-			dev->bus->pm->runtime_suspend(dev);
-
-	return 0;
-}
-
-static int omap_i2c_resume(struct device *dev)
-{
-	if (!pm_runtime_suspended(dev))
-		if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_resume)
-			dev->bus->pm->runtime_resume(dev);
-
-	return 0;
-}
-
-static struct dev_pm_ops omap_i2c_pm_ops = {
-	.suspend = omap_i2c_suspend,
-	.resume = omap_i2c_resume,
-};
-#define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
-#else
-#define OMAP_I2C_PM_OPS NULL
-#endif
-
 static struct platform_driver omap_i2c_driver = {
 	.probe		= omap_i2c_probe,
 	.remove		= omap_i2c_remove,
 	.driver		= {
 		.name	= "omap_i2c",
 		.owner	= THIS_MODULE,
-		.pm	= OMAP_I2C_PM_OPS,
 	},
 };
 
diff --git a/drivers/i2c/busses/i2c-pxa-pci.c b/drivers/i2c/busses/i2c-pxa-pci.c
index 6659d269b84..b73da6cd6f9 100644
--- a/drivers/i2c/busses/i2c-pxa-pci.c
+++ b/drivers/i2c/busses/i2c-pxa-pci.c
@@ -109,12 +109,15 @@ static int __devinit ce4100_i2c_probe(struct pci_dev *dev,
 		return -EINVAL;
 	}
 	sds = kzalloc(sizeof(*sds), GFP_KERNEL);
-	if (!sds)
+	if (!sds) {
+		ret = -ENOMEM;
 		goto err_mem;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) {
 		sds->pdev[i] = add_i2c_device(dev, i);
 		if (IS_ERR(sds->pdev[i])) {
+			ret = PTR_ERR(sds->pdev[i]);
 			while (--i >= 0)
 				platform_device_unregister(sds->pdev[i]);
 			goto err_dev_add;
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index fb3b4f8f815..3c94c4a81a5 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -26,6 +26,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/i2c-tegra.h>
+#include <linux/of_i2c.h>
 
 #include <asm/unaligned.h>
 
@@ -269,14 +270,30 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
 
 	/* Rounds down to not include partial word at the end of buf */
 	words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD;
-	if (words_to_transfer > tx_fifo_avail)
-		words_to_transfer = tx_fifo_avail;
 
-	i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer);
-
-	buf += words_to_transfer * BYTES_PER_FIFO_WORD;
-	buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
-	tx_fifo_avail -= words_to_transfer;
+	/* It's very common to have < 4 bytes, so optimize that case. */
+	if (words_to_transfer) {
+		if (words_to_transfer > tx_fifo_avail)
+			words_to_transfer = tx_fifo_avail;
+
+		/*
+		 * Update state before writing to FIFO.  If this casues us
+		 * to finish writing all bytes (AKA buf_remaining goes to 0) we
+		 * have a potential for an interrupt (PACKET_XFER_COMPLETE is
+		 * not maskable).  We need to make sure that the isr sees
+		 * buf_remaining as 0 and doesn't call us back re-entrantly.
+		 */
+		buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
+		tx_fifo_avail -= words_to_transfer;
+		i2c_dev->msg_buf_remaining = buf_remaining;
+		i2c_dev->msg_buf = buf +
+			words_to_transfer * BYTES_PER_FIFO_WORD;
+		barrier();
+
+		i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer);
+
+		buf += words_to_transfer * BYTES_PER_FIFO_WORD;
+	}
 
 	/*
 	 * If there is a partial word at the end of buf, handle it manually to
@@ -286,14 +303,15 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
 	if (tx_fifo_avail > 0 && buf_remaining > 0) {
 		BUG_ON(buf_remaining > 3);
 		memcpy(&val, buf, buf_remaining);
+
+		/* Again update before writing to FIFO to make sure isr sees. */
+		i2c_dev->msg_buf_remaining = 0;
+		i2c_dev->msg_buf = NULL;
+		barrier();
+
 		i2c_writel(i2c_dev, val, I2C_TX_FIFO);
-		buf_remaining = 0;
-		tx_fifo_avail--;
 	}
 
-	BUG_ON(tx_fifo_avail > 0 && buf_remaining > 0);
-	i2c_dev->msg_buf_remaining = buf_remaining;
-	i2c_dev->msg_buf = buf;
 	return 0;
 }
 
@@ -410,9 +428,10 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 			tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ);
 	}
 
-	if ((status & I2C_INT_PACKET_XFER_COMPLETE) &&
-			!i2c_dev->msg_buf_remaining)
+	if (status & I2C_INT_PACKET_XFER_COMPLETE) {
+		BUG_ON(i2c_dev->msg_buf_remaining);
 		complete(&i2c_dev->msg_complete);
+	}
 
 	i2c_writel(i2c_dev, status, I2C_INT_STATUS);
 	if (i2c_dev->is_dvc)
@@ -530,7 +549,7 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 
 static u32 tegra_i2c_func(struct i2c_adapter *adap)
 {
-	return I2C_FUNC_I2C;
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 }
 
 static const struct i2c_algorithm tegra_i2c_algo = {
@@ -546,6 +565,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	struct resource *iomem;
 	struct clk *clk;
 	struct clk *i2c_clk;
+	const unsigned int *prop;
 	void *base;
 	int irq;
 	int ret = 0;
@@ -603,7 +623,17 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	i2c_dev->irq = irq;
 	i2c_dev->cont_id = pdev->id;
 	i2c_dev->dev = &pdev->dev;
-	i2c_dev->bus_clk_rate = pdata ? pdata->bus_clk_rate : 100000;
+
+	i2c_dev->bus_clk_rate = 100000; /* default clock rate */
+	if (pdata) {
+		i2c_dev->bus_clk_rate = pdata->bus_clk_rate;
+
+	} else if (i2c_dev->dev->of_node) {    /* if there is a device tree node ... */
+		prop = of_get_property(i2c_dev->dev->of_node,
+				"clock-frequency", NULL);
+		if (prop)
+			i2c_dev->bus_clk_rate = be32_to_cpup(prop);
+	}
 
 	if (pdev->id == 3)
 		i2c_dev->is_dvc = 1;
@@ -633,6 +663,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	i2c_dev->adapter.algo = &tegra_i2c_algo;
 	i2c_dev->adapter.dev.parent = &pdev->dev;
 	i2c_dev->adapter.nr = pdev->id;
+	i2c_dev->adapter.dev.of_node = pdev->dev.of_node;
 
 	ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
 	if (ret) {
@@ -640,6 +671,8 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 		goto err_free_irq;
 	}
 
+	of_i2c_register_devices(&i2c_dev->adapter);
+
 	return 0;
 err_free_irq:
 	free_irq(i2c_dev->irq, i2c_dev);
@@ -704,6 +737,17 @@ static int tegra_i2c_resume(struct platform_device *pdev)
 }
 #endif
 
+#if defined(CONFIG_OF)
+/* Match table for of_platform binding */
+static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
+	{ .compatible = "nvidia,tegra20-i2c", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
+#else
+#define tegra_i2c_of_match NULL
+#endif
+
 static struct platform_driver tegra_i2c_driver = {
 	.probe   = tegra_i2c_probe,
 	.remove  = tegra_i2c_remove,
@@ -714,6 +758,7 @@ static struct platform_driver tegra_i2c_driver = {
 	.driver  = {
 		.name  = "tegra-i2c",
 		.owner = THIS_MODULE,
+		.of_match_table = tegra_i2c_of_match,
 	},
 };