input: rohm_bu21023: switch to i2c_lock_bus(..., I2C_LOCK_SEGMENT)

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 <peda@axentia.se>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/input/touchscreen/rohm_bu21023.c b/drivers/input/touchscreen/rohm_bu21023.c
index bda0500c9b5779ba250b7260b0d368f4462334aa..714affdd742fdaa446344fceb57ffaa80cdac492 100644 (file)
--- 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 i2c_client *client, u8 start, void *buf,
        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 i2c_client *client, u8 start, void *buf,
                }
        }
 
-       i2c_unlock_adapter(adap);
+       i2c_unlock_bus(adap, I2C_LOCK_SEGMENT);
 
        return ret;
 }