From c3701185ee1973845db088d8b0fc443397ab0eb2 Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Fri, 10 Mar 2023 19:22:48 -0500 Subject: 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 --- drivers/iio/dac/cio-dac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/iio/dac/cio-dac.c') diff --git a/drivers/iio/dac/cio-dac.c b/drivers/iio/dac/cio-dac.c index 791dd999cf29..18a64f72fc18 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; -- cgit v1.2.3-58-ga151