[PATCH v2] soundwire: Fix a signedness bug

Dan Carpenter
2018-01-10T12:29:11Z

"ret" is an int and "buf" is a u8. sdw_read() returns negative error
codes which are truncated to the u8, 0-255 range before being stored as
an int. It means that "ret" can't be less than zero.

Fixes: b0a9c37b0178 ("soundwire: Add slave status handling")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: style change

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index 4c345197eb55..ae698e63bdf6 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -771,7 +771,7 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave)
sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);

/* Read Instat 1, Instat 2 and Instat 3 registers */
- ret = buf = sdw_read(slave, SDW_SCP_INT1);
+ buf = ret = sdw_read(slave, SDW_SCP_INT1);
if (ret < 0) {
dev_err(slave->bus->dev,
"SDW_SCP_INT1 read failed:%d", ret);
@@ -870,7 +870,7 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave)
* Read status again to ensure no new interrupts arrived
* while servicing interrupts.
*/
- ret = _buf = sdw_read(slave, SDW_SCP_INT1);
+ _buf = ret = sdw_read(slave, SDW_SCP_INT1);
if (ret < 0) {
dev_err(slave->bus->dev,
"SDW_SCP_INT1 read failed:%d", ret);