From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> --- 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 636fd2efad8850..b3a70e8fc653c5 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_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 +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; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html