Signed-off-by: Wolfram Sang <w...@the-dreams.de>
---
 drivers/i2c/busses/i2c-at91.c | 32 +++++++++++---------------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 636fd2efad88..8be7cf6e2747 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -487,30 +487,10 @@ 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 +520,15 @@ 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_ADAPTER_QUIRK_COMB_WRITE_FIRST,
+       .max_comb_write_len = 3,
+};
+
 static u32 at91_twi_func(struct i2c_adapter *adapter)
 {
        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
@@ -777,6 +766,7 @@ 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;
-- 
2.1.3

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