1 files changed, 15 insertions, 24 deletions

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 636fd2efad88..ff23d1bdd230 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -381,6 +381,7 @@ static irqreturn_t atmel_twi_interrupt(int irq, void *dev_id)
 static int at91_do_twi_transfer(struct at91_twi_dev *dev)
 {
 	int ret;
+	unsigned long time_left;
 	bool has_unre_flag = dev->pdata->has_unre_flag;
 
 	dev_dbg(dev->dev, "transfer: %s %d bytes.\n",
@@ -436,9 +437,9 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
 		}
 	}
 
-	ret = wait_for_completion_timeout(&dev->cmd_complete,
-					     dev->adapter.timeout);
-	if (ret == 0) {
+	time_left = wait_for_completion_timeout(&dev->cmd_complete,
+					      dev->adapter.timeout);
+	if (time_left == 0) {
 		dev_err(dev->dev, "controller timed out\n");
 		at91_init_twi_bus(dev);
 		ret = -ETIMEDOUT;
@@ -487,30 +488,10 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
 	if (ret < 0)
 		goto out;
 
-	/*
-	 * The hardware can handle at most two messages concatenated by a
-	 * repeated start via it's internal address feature.
-	 */
-	if (num > 2) {
-		dev_err(dev->dev,
-			"cannot handle more than two concatenated messages.\n");
-		ret = 0;
-		goto out;
-	} else if (num == 2) {
+	if (num == 2) {
 		int internal_address = 0;
 		int i;
 
-		if (msg->flags & I2C_M_RD) {
-			dev_err(dev->dev, "first transfer must be write.\n");
-			ret = -EINVAL;
-			goto out;
-		}
-		if (msg->len > 3) {
-			dev_err(dev->dev, "first message size must be <= 3.\n");
-			ret = -EINVAL;
-			goto out;
-		}
-
 		/* 1st msg is put into the internal address, start with 2nd */
 		m_start = &msg[1];
 		for (i = 0; i < msg->len; ++i) {
@@ -540,6 +521,15 @@ out:
 	return ret;
 }
 
+/*
+ * The hardware can handle at most two messages concatenated by a
+ * repeated start via it's internal address feature.
+ */
+static struct i2c_adapter_quirks at91_twi_quirks = {
+	.flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR,
+	.max_comb_1st_msg_len = 3,
+};
+
 static u32 at91_twi_func(struct i2c_adapter *adapter)
 {
 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
@@ -777,6 +767,7 @@ static int at91_twi_probe(struct platform_device *pdev)
 	dev->adapter.owner = THIS_MODULE;
 	dev->adapter.class = I2C_CLASS_DEPRECATED;
 	dev->adapter.algo = &at91_twi_algorithm;
+	dev->adapter.quirks = &at91_twi_quirks;
 	dev->adapter.dev.parent = dev->dev;
 	dev->adapter.nr = pdev->id;
 	dev->adapter.timeout = AT91_I2C_TIMEOUT;