Commit c991bf9b authored by Alexandru Ardelean's avatar Alexandru Ardelean Committed by Jonathan Cameron
Browse files

iio: dac: ad7303: replace mlock with own lock 



This change replaces indio_dev's mlock with the driver's own lock. The lock
is mostly needed to protect state when changing the `dac_cache` info.
The lock has been extended to `ad7303_read_raw()`, to make sure that the
cache is updated if an SPI-write is already in progress.

Signed-off-by: default avatarAlexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent af8dc7bf

drivers/iio/dac/ad7303.c

+9 −4
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ struct ad7303_state { 
	struct regulator *vdd_reg;

	struct regulator *vref_reg;



	struct mutex lock;

	/*

	 * DMA (thus cache coherency maintenance) requires the

	 * transfer buffers to live in their own cache lines.
@@ -79,7 +80,7 @@ static ssize_t ad7303_write_dac_powerdown(struct iio_dev *indio_dev, 
	if (ret)

		return ret;



	mutex_lock(&indio_dev->mlock);

	mutex_lock(&st->lock);



	if (pwr_down)

		st->config |= AD7303_CFG_POWER_DOWN(chan->channel);
@@ -90,7 +91,7 @@ static ssize_t ad7303_write_dac_powerdown(struct iio_dev *indio_dev, 
	 * mode, so just write one of the DAC channels again */

	ad7303_write(st, chan->channel, st->dac_cache[chan->channel]);



	mutex_unlock(&indio_dev->mlock);

	mutex_unlock(&st->lock);

	return len;

}
@@ -116,7 +117,9 @@ static int ad7303_read_raw(struct iio_dev *indio_dev, 


	switch (info) {

	case IIO_CHAN_INFO_RAW:

		mutex_lock(&st->lock);

		*val = st->dac_cache[chan->channel];

		mutex_unlock(&st->lock);

		return IIO_VAL_INT;

	case IIO_CHAN_INFO_SCALE:

		vref_uv = ad7303_get_vref(st, chan);
@@ -144,11 +147,11 @@ static int ad7303_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 = ad7303_write(st, chan->address, val);

		if (ret == 0)

			st->dac_cache[chan->channel] = val;

		mutex_unlock(&indio_dev->mlock);

		mutex_unlock(&st->lock);

		break;

	default:

		ret = -EINVAL;
@@ -211,6 +214,8 @@ static int ad7303_probe(struct spi_device *spi) 


	st->spi = spi;



	mutex_init(&st->lock);



	st->vdd_reg = devm_regulator_get(&spi->dev, "Vdd");

	if (IS_ERR(st->vdd_reg))

		return PTR_ERR(st->vdd_reg);

CRA Git | Maintained and supported by SUSTech CRA and CCSE