This is a note to let you know that I've just added the patch titled
iio: addac: stx104: Fix race condition when converting
to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-next branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release during the merge window.
If you have any questions about this process, please let me know.
From 4f9b80aefb9e2f542a49d9ec087cf5919730e1dd Mon Sep 17 00:00:00 2001 From: William Breathitt Gray william.gray@linaro.org Date: Thu, 6 Apr 2023 10:40:11 -0400 Subject: 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/2ae5e40eed5006ca735e4c12181a9ff5ced65547.168079058... Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- drivers/iio/addac/stx104.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/iio/addac/stx104.c b/drivers/iio/addac/stx104.c index 4239aafe42fc..8730b79e921c 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 */