From: William Breathitt Gray Date: Sat, 11 Mar 2023 00:22:48 +0000 (-0500) Subject: iio: dac: cio-dac: Fix max DAC write value check for 12-bit X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c3701185ee1973845db088d8b0fc443397ab0eb2;p=linux.git iio: dac: cio-dac: Fix max DAC write value check for 12-bit The CIO-DAC series of devices only supports DAC values up to 12-bit rather than 16-bit. Trying to write a 16-bit value results in only the lower 12 bits affecting the DAC output which is not what the user expects. Instead, adjust the DAC write value check to reject values larger than 12-bit so that they fail explicitly as invalid for the user. Fixes: 3b8df5fd526e ("iio: Add IIO support for the Measurement Computing CIO-DAC family") Cc: stable@vger.kernel.org Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/20230311002248.8548-1-william.gray@linaro.org Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/dac/cio-dac.c b/drivers/iio/dac/cio-dac.c index 791dd999cf291..18a64f72fc188 100644 --- a/drivers/iio/dac/cio-dac.c +++ b/drivers/iio/dac/cio-dac.c @@ -66,8 +66,8 @@ static int cio_dac_write_raw(struct iio_dev *indio_dev, if (mask != IIO_CHAN_INFO_RAW) return -EINVAL; - /* DAC can only accept up to a 16-bit value */ - if ((unsigned int)val > 65535) + /* DAC can only accept up to a 12-bit value */ + if ((unsigned int)val > 4095) return -EINVAL; priv->chan_out_states[chan->channel] = val;