staging: iio: ad7280: Replace mlock with driver private lock

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: Gargi Sharma <gs051095@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
index ee679ac0368f86dd1671abf9aef3297401ca805a..6a85e284c8a424955dc8d3b77eeabcb975dbbea5 100644 (file)
--- a/drivers/staging/iio/adc/ad7280a.c
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -134,6 +134,7 @@ struct ad7280_state {
        unsigned char                   aux_threshhigh;
        unsigned char                   aux_threshlow;
        unsigned char                   cb_mask[AD7280A_MAX_CHAIN];
+       struct mutex                    lock; /* protect sensor state */
 
        __be32                          buf[2] ____cacheline_aligned;
 };
@@ -410,7 +411,7 @@ static ssize_t ad7280_store_balance_sw(struct device *dev,
        devaddr = this_attr->address >> 8;
        ch = this_attr->address & 0xFF;
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
        if (readin)
                st->cb_mask[devaddr] |= 1 << (ch + 2);
        else
@@ -418,7 +419,7 @@ static ssize_t ad7280_store_balance_sw(struct device *dev,
 
        ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
                           0, st->cb_mask[devaddr]);
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        return ret ? ret : len;
 }
@@ -433,10 +434,10 @@ static ssize_t ad7280_show_balance_timer(struct device *dev,
        int ret;
        unsigned int msecs;
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
        ret = ad7280_read(st, this_attr->address >> 8,
                          this_attr->address & 0xFF);
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        if (ret < 0)
                return ret;
@@ -466,11 +467,11 @@ static ssize_t ad7280_store_balance_timer(struct device *dev,
        if (val > 31)
                return -EINVAL;
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
        ret = ad7280_write(st, this_attr->address >> 8,
                           this_attr->address & 0xFF,
                           0, (val & 0x1F) << 3);
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        return ret ? ret : len;
 }
@@ -655,7 +656,7 @@ static ssize_t ad7280_write_channel_config(struct device *dev,
 
        val = clamp(val, 0L, 0xFFL);
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
        switch ((u32)this_attr->address) {
        case AD7280A_CELL_OVERVOLTAGE:
                st->cell_threshhigh = val;
@@ -674,7 +675,7 @@ static ssize_t ad7280_write_channel_config(struct device *dev,
        ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
                           this_attr->address, 1, val);
 
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        return ret ? ret : len;
 }
@@ -792,13 +793,13 @@ static int ad7280_read_raw(struct iio_dev *indio_dev,
 
        switch (m) {
        case IIO_CHAN_INFO_RAW:
-               mutex_lock(&indio_dev->mlock);
+               mutex_lock(&st->lock);
                if (chan->address == AD7280A_ALL_CELLS)
                        ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
                else
                        ret = ad7280_read_channel(st, chan->address >> 8,
                                                  chan->address & 0xFF);
-               mutex_unlock(&indio_dev->mlock);
+               mutex_unlock(&st->lock);
 
                if (ret < 0)
                        return ret;
@@ -847,6 +848,7 @@ static int ad7280_probe(struct spi_device *spi)
        st = iio_priv(indio_dev);
        spi_set_drvdata(spi, indio_dev);
        st->spi = spi;
+       mutex_init(&st->lock);
 
        if (!pdata)
                pdata = &ad7793_default_pdata;