From: Lukas Schmid Date: Mon, 2 Feb 2026 20:15:35 +0000 (+0100) Subject: iio: potentiometer: mcp4131: fix double application of wiper shift X-Git-Tag: v7.0-rc4~15^2~7^2~14 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=85e4614524dca6c0a43874f475a17de2b9725648;p=thirdparty%2Fkernel%2Fstable.git 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: 22d199a53910 ("iio: potentiometer: add driver for Microchip MCP413X/414X/415X/416X/423X/424X/425X/426X") Signed-off-by: Lukas Schmid # Cc: Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/potentiometer/mcp4131.c b/drivers/iio/potentiometer/mcp4131.c index ad082827aad5e..56c9111ef5e81 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 */