diff options
| author | Marcus Folkesson <marcus.folkesson@gmail.com> | 2018-08-24 22:24:40 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-11-25 09:51:59 +0100 |
| commit | b7f8108a1cd47a12fd1f9d432d69ad4f049d0582 (patch) | |
| tree | e4250bab056fd0e7635641646e31d1132764ff92 | |
| parent | 35940da897ed4760608b7fb01850a9923fd0965f (diff) | |
iio: dac: mcp4922: fix error handling in mcp4922_write_raw
[ Upstream commit 0833627fc3f757a0dca11e2a9c46c96335a900ee ]
Do not try to write negative values and make sure that the write goes well.
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/iio/dac/mcp4922.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/iio/dac/mcp4922.c b/drivers/iio/dac/mcp4922.c index 3854d201a5d6..68dd0be1ac07 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; } |