From 0833627fc3f757a0dca11e2a9c46c96335a900ee Mon Sep 17 00:00:00 2001 From: Marcus Folkesson Date: Fri, 24 Aug 2018 22:24:40 +0200 Subject: [PATCH] iio: dac: mcp4922: fix error handling in mcp4922_write_raw Do not try to write negative values and make sure that the write goes well. Signed-off-by: Marcus Folkesson Signed-off-by: Jonathan Cameron --- 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; }