4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Peter Rosin <[email protected]> [ Upstream commit 193c2a07cfaacb9249ab0e3d34bce32490879355 ] Locking the root adapter for __i2c_transfer will deadlock if the device sits behind a mux-locked I2C mux. Switch to the finer-grained i2c_lock_bus with the I2C_LOCK_SEGMENT flag. If the device does not sit behind a mux-locked mux, the two locking variants are equivalent. Signed-off-by: Peter Rosin <[email protected]> Acked-by: Dmitry Torokhov <[email protected]> Signed-off-by: Wolfram Sang <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/input/touchscreen/rohm_bu21023.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/input/touchscreen/rohm_bu21023.c +++ b/drivers/input/touchscreen/rohm_bu21023.c @@ -304,7 +304,7 @@ static int rohm_i2c_burst_read(struct i2 msg[1].len = len; msg[1].buf = buf; - i2c_lock_adapter(adap); + i2c_lock_bus(adap, I2C_LOCK_SEGMENT); for (i = 0; i < 2; i++) { if (__i2c_transfer(adap, &msg[i], 1) < 0) { @@ -313,7 +313,7 @@ static int rohm_i2c_burst_read(struct i2 } } - i2c_unlock_adapter(adap); + i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); return ret; }
