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Subject: [PATCH v2 03/10] input: rohm_bu21023: switch to i2c_lock_bus(..., I2C_LOCK_SEGMENT)
Date:   Wed, 20 Jun 2018 07:17:56 +0200
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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>
---
 drivers/input/touchscreen/rohm_bu21023.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/input/touchscreen/rohm_bu21023.c b/drivers/input/touchscreen/rohm_bu21023.c
index bda0500c9b57..714affdd742f 100644
--- 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;
 }
-- 
2.11.0