This is a note to let you know that I've just added the patch titled
iio: adc: ad9467: add mutex to struct ad9467_state
to the 6.6-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-adc-ad9467-add-mutex-to-struct-ad9467_state.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit bcff0530ed788c98b41c0424d6275952c3e420ee
Author: Nuno Sa <nuno.sa@xxxxxxxxxx>
Date: Thu Dec 7 13:39:26 2023 +0100
iio: adc: ad9467: add mutex to struct ad9467_state
[ Upstream commit 737720197be445bb9eec2986101e4a386e019337 ]
When calling ad9467_set_scale(), multiple calls to ad9467_spi_write()
are done which means we need to properly protect the whole operation so
we are sure we will be in a sane state if two concurrent calls occur.
Fixes: ad6797120238 ("iio: adc: ad9467: add support AD9467 ADC")
Signed-off-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
Reviewed-by: David Lechner <dlechner@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20231207-iio-backend-prep-v2-3-a4a33bc4d70e@xxxxxxxxxx
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c
index d3c98c4eccd3..104c6d394a3e 100644
--- a/drivers/iio/adc/ad9467.c
+++ b/drivers/iio/adc/ad9467.c
@@ -4,8 +4,9 @@
*
* Copyright 2012-2020 Analog Devices Inc.
*/
-
+#include <linux/cleanup.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
@@ -121,6 +122,8 @@ struct ad9467_state {
unsigned int output_mode;
struct gpio_desc *pwrdown_gpio;
+ /* ensure consistent state obtained on multiple related accesses */
+ struct mutex lock;
};
static int ad9467_spi_read(struct spi_device *spi, unsigned int reg)
@@ -161,6 +164,7 @@ static int ad9467_reg_access(struct adi_axi_adc_conv *conv, unsigned int reg,
int ret;
if (readval == NULL) {
+ guard(mutex)(&st->lock);
ret = ad9467_spi_write(spi, reg, writeval);
if (ret)
return ret;
@@ -310,6 +314,7 @@ static int ad9467_set_scale(struct adi_axi_adc_conv *conv, int val, int val2)
if (scale_val[0] != val || scale_val[1] != val2)
continue;
+ guard(mutex)(&st->lock);
ret = ad9467_spi_write(st->spi, AN877_ADC_REG_VREF,
info->scale_table[i][1]);
if (ret < 0)
