| Message ID | 20180824202440.21754-1-marcus.folkesson@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: dac: mcp4922: fix error handling in mcp4922_write_raw | expand |
On Fri, 24 Aug 2018 22:24:40 +0200 Marcus Folkesson <marcus.folkesson@gmail.com> 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@gmail.com> > --- > 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; > }
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; }
Do not try to write negative values and make sure that the write goes well. Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> --- drivers/iio/dac/mcp4922.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)