diff options
| author | Oleksij Rempel <o.rempel@pengutronix.de> | 2026-02-04 15:00:33 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-03-19 16:15:29 +0100 |
| commit | 8d6a232f918eac3b5dd05481f9902c1d8f4d5204 (patch) | |
| tree | 23b09634eeca69b5746f15bca0e7c30a44463520 | |
| parent | e7b9356d8f4a6864529e0436f0dcc604d3b63b69 (diff) | |
iio: dac: ds4424: reject -128 RAW value
commit 5187e03b817c26c1c3bcb2645a612ea935c4be89 upstream.
The DS442x DAC uses sign-magnitude encoding, so -128 cannot be represented
in hardware (7-bit magnitude).
Previously, passing -128 resulted in a truncated value that programmed
0mA (magnitude 0) instead of the expected maximum negative current,
effectively failing silently.
Reject -128 to avoid producing the wrong current.
Fixes: d632a2bd8ffc ("iio: dac: ds4422/ds4424 dac driver")
Cc: stable@vger.kernel.org
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/iio/dac/ds4424.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/iio/dac/ds4424.c b/drivers/iio/dac/ds4424.c index a8198ba4f98a..059acca45f64 100644 --- a/drivers/iio/dac/ds4424.c +++ b/drivers/iio/dac/ds4424.c @@ -141,7 +141,7 @@ static int ds4424_write_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_RAW: - if (val < S8_MIN || val > S8_MAX) + if (val <= S8_MIN || val > S8_MAX) return -EINVAL; if (val > 0) { |