[PATCH] iio: dac: ad5686: Replace indio_dev->mlock with own device lock

From: Sergiu Cuciurean
Date: Thu May 14 2020 - 05:20:13 EST


As part of the general cleanup of indio_dev->mlock, this change replaces
it with a local lock on the device's state structure.

Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
---
drivers/iio/dac/ad5686.c | 10 ++++++----
drivers/iio/dac/ad5686.h | 2 ++
2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index e06b29c565b9..8dd67da0a7da 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -127,9 +127,9 @@ static int ad5686_read_raw(struct iio_dev *indio_dev,

switch (m) {
case IIO_CHAN_INFO_RAW:
- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
ret = st->read(st, chan->address);
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);
if (ret < 0)
return ret;
*val = (ret >> chan->scan_type.shift) &
@@ -157,12 +157,12 @@ static int ad5686_write_raw(struct iio_dev *indio_dev,
if (val > (1 << chan->scan_type.realbits) || val < 0)
return -EINVAL;

- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
ret = st->write(st,
AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
chan->address,
val << chan->scan_type.shift);
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);
break;
default:
ret = -EINVAL;
@@ -468,6 +468,8 @@ int ad5686_probe(struct device *dev,
indio_dev->channels = st->chip_info->channels;
indio_dev->num_channels = st->chip_info->num_channels;

+ mutex_init(&st->lock);
+
switch (st->chip_info->regmap_type) {
case AD5310_REGMAP:
cmd = AD5686_CMD_CONTROL_REG;
diff --git a/drivers/iio/dac/ad5686.h b/drivers/iio/dac/ad5686.h
index 70a779939ddb..52009b5eef88 100644
--- a/drivers/iio/dac/ad5686.h
+++ b/drivers/iio/dac/ad5686.h
@@ -117,6 +117,7 @@ struct ad5686_chip_info {
* @pwr_down_mask: power down mask
* @pwr_down_mode: current power down mode
* @use_internal_vref: set to true if the internal reference voltage is used
+ * @lock lock to protect the data buffer during regmap ops
* @data: spi transfer buffers
*/

@@ -130,6 +131,7 @@ struct ad5686_state {
ad5686_write_func write;
ad5686_read_func read;
bool use_internal_vref;
+ struct mutex lock;

/*
* DMA (thus cache coherency maintenance) requires the
--
2.17.1