Zero-length message support (SMBUS QUICK or i2c) never worked with the Octeon hardware. Disable SMBUS QUICK support and bail out in case of a zero-length i2c request.
After this change 'i2c-detect -q' will return an error on Octeon but the previously reported results were wrong anyway. Signed-off-by: Jan Glauber <jglau...@cavium.com> --- drivers/i2c/busses/i2c-octeon.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c index 9f11e19..e8a65f5 100644 --- a/drivers/i2c/busses/i2c-octeon.c +++ b/drivers/i2c/busses/i2c-octeon.c @@ -837,9 +837,6 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target, int i, result, length = *rlength; bool final_read = false; - if (length < 1) - return -EINVAL; - octeon_i2c_data_write(i2c, (target << 1) | 1); octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); @@ -925,6 +922,12 @@ static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, for (i = 0; ret == 0 && i < num; i++) { struct i2c_msg *pmsg = &msgs[i]; + /* zero-length messages are not supported */ + if (!pmsg->len) { + ret = -EOPNOTSUPP; + break; + } + ret = octeon_i2c_start(i2c); if (ret) return ret; @@ -998,7 +1001,7 @@ static struct i2c_bus_recovery_info octeon_i2c_recovery_info = { static u32 octeon_i2c_functionality(struct i2c_adapter *adap) { - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL; } -- 1.9.1