[PATCH 3.10 312/319] hwmon: (adt7411) set bit 3 in CFG1 register

Willy Tarreau
2017-02-05T19:56:00Z

From: Michael Walle <michael@walle.cc>

commit b53893aae441a034bf4dbbad42fe218561d7d81f upstream.

According to the datasheet you should only write 1 to this bit. If it is
not set, at least AIN3 will return bad values on newer silicon revisions.

Fixes: d84ca5b345c2 ("hwmon: Add driver for ADT7411 voltage and temperature sensor")
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/hwmon/adt7411.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/adt7411.c b/drivers/hwmon/adt7411.c
index d9299dee..dddaa16 100644
--- a/drivers/hwmon/adt7411.c
+++ b/drivers/hwmon/adt7411.c
@@ -30,6 +30,7 @@

#define ADT7411_REG_CFG1 0x18
#define ADT7411_CFG1_START_MONITOR (1 << 0)
+#define ADT7411_CFG1_RESERVED_BIT3 (1 << 3)

#define ADT7411_REG_CFG2 0x19
#define ADT7411_CFG2_DISABLE_AVG (1 << 5)
@@ -292,8 +293,10 @@ static int adt7411_probe(struct i2c_client *client,
mutex_init(&data->device_lock);
mutex_init(&data->update_lock);

+ /* According to the datasheet, we must only write 1 to bit 3 */
ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
- ADT7411_CFG1_START_MONITOR, 1);
+ ADT7411_CFG1_RESERVED_BIT3
+ | ADT7411_CFG1_START_MONITOR, 1);
if (ret < 0)
return ret;

--
2.8.0.rc2.1.gbe9624a