[PATCH v4] staging: iio: ade7753: Replace mlock with driver private lock

simran singhal
2017-03-23T18:35:27Z

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: simran singhal <singhalsimran0@gmail.com>
---

v4:
-Add mutex_init

drivers/staging/iio/meter/ade7753.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/iio/meter/ade7753.c b/drivers/staging/iio/meter/ade7753.c
index b71fbd3..30aebaf 100644
--- a/drivers/staging/iio/meter/ade7753.c
+++ b/drivers/staging/iio/meter/ade7753.c
@@ -80,11 +80,13 @@
* @us: actual spi_device
* @tx: transmit buffer
* @rx: receive buffer
+ * @lock: protect sensor state
* @buf_lock: mutex to protect tx and rx
**/
struct ade7753_state {
struct spi_device *us;
struct mutex buf_lock;
+ struct mutex lock; /* protect sensor state */
u8 tx[ADE7753_MAX_TX] ____cacheline_aligned;
u8 rx[ADE7753_MAX_RX];
};
@@ -484,7 +486,7 @@ static ssize_t ade7753_write_frequency(struct device *dev,
if (!val)
return -EINVAL;

- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);

t = 27900 / val;
if (t > 0)
@@ -505,7 +507,7 @@ static ssize_t ade7753_write_frequency(struct device *dev,
ret = ade7753_spi_write_reg_16(dev, ADE7753_MODE, reg);

out:
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);

return ret ? ret : len;
}
@@ -581,6 +583,7 @@ static int ade7753_probe(struct spi_device *spi)
st = iio_priv(indio_dev);
st->us = spi;
mutex_init(&st->buf_lock);
+ mutex_init(&st->lock);

indio_dev->name = spi->dev.driver->name;
indio_dev->dev.parent = &spi->dev;
--
2.7.4