On Fri, 24 Aug 2018 22:24:40 +0200
Marcus Folkesson <marcus.folkesson@xxxxxxxxx> wrote:
> Do not try to write negative values and make sure that the write goes well.
>
+CC Michael as it's his driver.
I'll take this as it 'appears' straight forward but I won't be pushing
it out as a non rebasing branch for a few days if I've missed anything.
Applied to the togreg branch of iio.git and pushed out for now as testing
for the autobuilders to play with it.
Thanks,
Jonathan
> Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> ---
> drivers/iio/dac/mcp4922.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/dac/mcp4922.c b/drivers/iio/dac/mcp4922.c
> index bf9aa3fc0534..b5190d1dae8e 100644
> --- a/drivers/iio/dac/mcp4922.c
> +++ b/drivers/iio/dac/mcp4922.c
> @@ -94,17 +94,22 @@ static int mcp4922_write_raw(struct iio_dev *indio_dev,
> long mask)
> {
> struct mcp4922_state *state = iio_priv(indio_dev);
> + int ret;
>
> if (val2 != 0)
> return -EINVAL;
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> - if (val > GENMASK(chan->scan_type.realbits-1, 0))
> + if (val < 0 || val > GENMASK(chan->scan_type.realbits - 1, 0))
> return -EINVAL;
> val <<= chan->scan_type.shift;
> - state->value[chan->channel] = val;
> - return mcp4922_spi_write(state, chan->channel, val);
> +
> + ret = mcp4922_spi_write(state, chan->channel, val);
> + if (!ret)
> + state->value[chan->channel] = val;
> + return ret;
> +
> default:
> return -EINVAL;
> }
