[RESEND PATCH] staging: ad7606: Replace mlock with driver private lock

From: Arushi Singhal
Date: Mon Mar 20 2017 - 11:23:07 EST


The IIO subsystem is redefining iio_dev->mlock to be used by
the IIO core only for protecting device operating mode changes.
ie. Changes between INDIO_DIRECT_MODE, INDIO_BUFFER_* modes.

In this driver, mlock was being used to protect hardware state
changes. Replace it with a lock in the devices global data.

Signed-off-by: Arushi Singhal <arushisinghal19971997@xxxxxxxxx>
---
drivers/staging/iio/adc/ad7606.c | 8 ++++----
drivers/staging/iio/adc/ad7606.h | 2 ++
2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7606.c b/drivers/staging/iio/adc/ad7606.c
index 9dbfa64b1e53..9f529b34e018 100644
--- a/drivers/staging/iio/adc/ad7606.c
+++ b/drivers/staging/iio/adc/ad7606.c
@@ -208,7 +208,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
switch (mask) {
case IIO_CHAN_INFO_SCALE:
ret = -EINVAL;
- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
for (i = 0; i < ARRAY_SIZE(scale_avail); i++)
if (val2 == scale_avail[i][1]) {
gpiod_set_value(st->gpio_range, i);
@@ -217,7 +217,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
ret = 0;
break;
}
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);

return ret;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
@@ -231,11 +231,11 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
values[1] = (ret >> 1) & 1;
values[2] = (ret >> 2) & 1;

- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
values);
st->oversampling = val;
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);

return 0;
default:
diff --git a/drivers/staging/iio/adc/ad7606.h b/drivers/staging/iio/adc/ad7606.h
index 746f9553d2ba..5d59bdd78727 100644
--- a/drivers/staging/iio/adc/ad7606.h
+++ b/drivers/staging/iio/adc/ad7606.h
@@ -14,6 +14,7 @@
* @name: identification string for chip
* @channels: channel specification
* @num_channels: number of channels
+ * @lock protect sensor state
*/

struct ad7606_chip_info {
@@ -37,6 +38,7 @@ struct ad7606_state {
bool done;
void __iomem *base_address;

+ struct mutex lock; /* protect sensor state */
struct gpio_desc *gpio_convst;
struct gpio_desc *gpio_reset;
struct gpio_desc *gpio_range;
--
2.11.0