diff options
| author | William Breathitt Gray <william.gray@linaro.org> | 2023-04-06 10:40:11 -0400 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2023-04-10 12:26:33 +0100 |
| commit | 4f9b80aefb9e2f542a49d9ec087cf5919730e1dd (patch) | |
| tree | 0aec9dc276c3bad1604534542e4c4797dff91d07 | |
| parent | 9740827468cea80c42db29e7171a50e99acf7328 (diff) | |
| download | iio-4f9b80aefb9e2f542a49d9ec087cf5919730e1dd.tar.gz | |
iio: addac: stx104: Fix race condition when converting analog-to-digital
The ADC conversion procedure requires several device I/O operations
performed in a particular sequence. If stx104_read_raw() is called
concurrently, the ADC conversion procedure could be clobbered. Prevent
such a race condition by utilizing a mutex.
Fixes: 4075a283ae83 ("iio: stx104: Add IIO support for the ADC channels")
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/2ae5e40eed5006ca735e4c12181a9ff5ced65547.1680790580.git.william.gray@linaro.org
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
| -rw-r--r-- | drivers/iio/addac/stx104.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/iio/addac/stx104.c b/drivers/iio/addac/stx104.c index 4239aafe42fc8..8730b79e921c8 100644 --- a/drivers/iio/addac/stx104.c +++ b/drivers/iio/addac/stx104.c @@ -117,6 +117,8 @@ static int stx104_read_raw(struct iio_dev *indio_dev, return IIO_VAL_INT; } + mutex_lock(&priv->lock); + /* select ADC channel */ iowrite8(chan->channel | (chan->channel << 4), ®->achan); @@ -127,6 +129,8 @@ static int stx104_read_raw(struct iio_dev *indio_dev, while (ioread8(®->cir_asr) & BIT(7)); *val = ioread16(®->ssr_ad); + + mutex_unlock(&priv->lock); return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: /* get ADC bipolar/unipolar configuration */ |