[PATCH v1] iio: potentiometer: mcp4131: fix double application of wiper shift

[PATCH v1] iio: potentiometer: mcp4131: fix double application of wiper shift

[Lukas Schmid]

The MCP4131 wiper address is shifted twice when preparing the SPI
command in mcp4131_write_raw().

The address is already shifted when assigned to the local variable
"address", but is then shifted again when written to data->buf[0].
This results in an incorrect command being sent to the device and
breaks wiper writes to the second channel.

Remove the second shift and use the pre-shifted address directly
when composing the SPI transfer.

Signed-off-by: Lukas Schmid <lukas.schmid@netcube.li>
---
 drivers/iio/potentiometer/mcp4131.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/potentiometer/mcp4131.c b/drivers/iio/potentiometer/mcp4131.c
index ad082827aad5..56c9111ef5e8 100644
--- a/drivers/iio/potentiometer/mcp4131.c
+++ b/drivers/iio/potentiometer/mcp4131.c
@@ -221,7 +221,7 @@ static int mcp4131_write_raw(struct iio_dev *indio_dev,
 
 	mutex_lock(&data->lock);
 
-	data->buf[0] = address << MCP4131_WIPER_SHIFT;
+	data->buf[0] = address;
 	data->buf[0] |= MCP4131_WRITE | (val >> 8);
 	data->buf[1] = val & 0xFF; /* 8 bits here */
 
-- 
2.47.3