Commit 85e46145 authored by Lukas Schmid's avatar Lukas Schmid Committed by Jonathan Cameron
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iio: potentiometer: mcp4131: fix double application of wiper shift 



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.

Fixes: 22d199a5 ("iio: potentiometer: add driver for Microchip MCP413X/414X/415X/416X/423X/424X/425X/426X")
Signed-off-by: default avatarLukas Schmid <lukas.schmid@netcube.li&gt;#>
Cc: <Stable@vger.kernel.org>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent d23d763e

drivers/iio/potentiometer/mcp4131.c

+1 −1
Original line number Diff line number Diff line
@@ -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 */