Patch "iio: addac: stx104: Fix race condition when converting analog-to-digital" has been added to the 6.1-stable tree

[<gregkh@xxxxxxxxxxxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    iio: addac: stx104: Fix race condition when converting analog-to-digital

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     iio-addac-stx104-fix-race-condition-when-converting-analog-to-digital.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 4f9b80aefb9e2f542a49d9ec087cf5919730e1dd Mon Sep 17 00:00:00 2001
From: William Breathitt Gray <william.gray@xxxxxxxxxx>
Date: Thu, 6 Apr 2023 10:40:11 -0400
Subject: iio: addac: stx104: Fix race condition when converting analog-to-digital

From: William Breathitt Gray <william.gray@xxxxxxxxxx>

commit 4f9b80aefb9e2f542a49d9ec087cf5919730e1dd upstream.

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@xxxxxxxxxx>
Link: https://lore.kernel.org/r/2ae5e40eed5006ca735e4c12181a9ff5ced65547.1680790580.git.william.gray@xxxxxxxxxx
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/iio/addac/stx104.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/iio/addac/stx104.c
+++ b/drivers/iio/addac/stx104.c
@@ -114,6 +114,8 @@ static int stx104_read_raw(struct iio_de
 			return IIO_VAL_INT;
 		}
 
+		mutex_lock(&priv->lock);
+
 		/* select ADC channel */
 		iowrite8(chan->channel | (chan->channel << 4), &reg->achan);
 
@@ -124,6 +126,8 @@ static int stx104_read_raw(struct iio_de
 		while (ioread8(&reg->cir_asr) & BIT(7));
 
 		*val = ioread16(&reg->ssr_ad);
+
+		mutex_unlock(&priv->lock);
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_OFFSET:
 		/* get ADC bipolar/unipolar configuration */


Patches currently in stable-queue which might be from william.gray@xxxxxxxxxx are

queue-6.1/iio-addac-stx104-fix-race-condition-when-converting-analog-to-digital.patch
queue-6.1/iio-addac-stx104-fix-race-condition-for-stx104_write_raw.patch