The i2c-powermac driver doesn't support arbitrary multi-message I2C transactions, only SMBus ones. Make it clear by returning an error if a multi-message I2C transaction is attempted. This is better than only processing the first message, because most callers won't recover from the short transaction. Anyone wishing to issue multi-message transactions should use the SMBus API instead of the raw I2C API.
Signed-off-by: Jean Delvare <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> --- drivers/i2c/busses/i2c-powermac.c | 6 ++++++ 1 file changed, 6 insertions(+) --- linux-2.6.32-rc1.orig/drivers/i2c/busses/i2c-powermac.c 2009-06-10 05:05:27.000000000 +0200 +++ linux-2.6.32-rc1/drivers/i2c/busses/i2c-powermac.c 2009-09-30 20:29:42.000000000 +0200 @@ -146,6 +146,12 @@ static int i2c_powermac_master_xfer( str int read; int addrdir; + if (num != 1) { + dev_err(&adap->dev, + "Multi-message I2C transactions not supported\n"); + return -EOPNOTSUPP; + } + if (msgs->flags & I2C_M_TEN) return -EINVAL; read = (msgs->flags & I2C_M_RD) != 0; -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
