3.11.10.11 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Wolfram Sang <[email protected]> commit d7653964c590ba846aa11a8f6edf409773cbc492 upstream. This hardware does not support zero length transfers. Instead, the driver does one (random) byte transfers currently with undefined results for the slaves. We now bail out. Signed-off-by: Wolfram Sang <[email protected]> Signed-off-by: Wolfram Sang <[email protected]> Signed-off-by: Luis Henriques <[email protected]> --- drivers/i2c/busses/i2c-rcar.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 0fc585861610..820b140061c9 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -541,6 +541,12 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap, ret = -EINVAL; for (i = 0; i < num; i++) { + /* This HW can't send STOP after address phase */ + if (msgs[i].len == 0) { + ret = -EOPNOTSUPP; + break; + } + /*-------------- spin lock -----------------*/ spin_lock_irqsave(&priv->lock, flags); @@ -605,7 +611,8 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap, static u32 rcar_i2c_func(struct i2c_adapter *adap) { - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; + /* This HW can't do SMBUS_QUICK and NOSTART */ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); } static const struct i2c_algorithm rcar_i2c_algo = { -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
