iio: dac: ad5360: Replace indio_dev->mlock with own device lock

As part of the general cleanup of indio_dev->mlock, this change replaces
it with a local lock on the device's state structure.
This also changes some internal functions to pass the pointer to the
state-struct vs a ref to indio_dev just to access the state-struct again.

Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/dac/ad5360.c b/drivers/iio/dac/ad5360.c
index 2ac428b..3e0c9e8 100644 (file)
--- a/drivers/iio/dac/ad5360.c
+++ b/drivers/iio/dac/ad5360.c
@@ -67,6 +67,7 @@ struct ad5360_chip_info {
  * @chip_info:         chip model specific constants, available modes etc
  * @vref_reg:          vref supply regulators
  * @ctrl:              control register cache
+ * @lock               lock to protect the data buffer during SPI ops
  * @data:              spi transfer buffers
  */
 
@@ -75,6 +76,7 @@ struct ad5360_state {
        const struct ad5360_chip_info   *chip_info;
        struct regulator_bulk_data      vref_reg[3];
        unsigned int                    ctrl;
+       struct mutex                    lock;
 
        /*
         * DMA (thus cache coherency maintenance) requires the
@@ -205,10 +207,11 @@ static int ad5360_write(struct iio_dev *indio_dev, unsigned int cmd,
        unsigned int addr, unsigned int val, unsigned int shift)
 {
        int ret;
+       struct ad5360_state *st = iio_priv(indio_dev);
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
        ret = ad5360_write_unlocked(indio_dev, cmd, addr, val, shift);
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        return ret;
 }
@@ -229,7 +232,7 @@ static int ad5360_read(struct iio_dev *indio_dev, unsigned int type,
                },
        };
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
 
        st->data[0].d32 = cpu_to_be32(AD5360_CMD(AD5360_CMD_SPECIAL_FUNCTION) |
                AD5360_ADDR(AD5360_REG_SF_READBACK) |
@@ -240,7 +243,7 @@ static int ad5360_read(struct iio_dev *indio_dev, unsigned int type,
        if (ret >= 0)
                ret = be32_to_cpu(st->data[1].d32) & 0xffff;
 
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        return ret;
 }
@@ -261,7 +264,7 @@ static int ad5360_update_ctrl(struct iio_dev *indio_dev, unsigned int set,
        struct ad5360_state *st = iio_priv(indio_dev);
        unsigned int ret;
 
-       mutex_lock(&indio_dev->mlock);
+       mutex_lock(&st->lock);
 
        st->ctrl |= set;
        st->ctrl &= ~clr;
@@ -269,7 +272,7 @@ static int ad5360_update_ctrl(struct iio_dev *indio_dev, unsigned int set,
        ret = ad5360_write_unlocked(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,
                        AD5360_REG_SF_CTRL, st->ctrl, 0);
 
-       mutex_unlock(&indio_dev->mlock);
+       mutex_unlock(&st->lock);
 
        return ret;
 }
@@ -479,6 +482,8 @@ static int ad5360_probe(struct spi_device *spi)
        indio_dev->modes = INDIO_DIRECT_MODE;
        indio_dev->num_channels = st->chip_info->num_channels;
 
+       mutex_init(&st->lock);
+
        ret = ad5360_alloc_channels(indio_dev);
        if (ret) {
                dev_err(&spi->dev, "Failed to allocate channel spec: %d\n", ret);