Commit abbde279 authored by Justin Chen's avatar Justin Chen Committed by Jonathan Cameron
Browse files

iio: adc: ti-ads7950: Fix improper use of mlock



Indio->mlock is used for protecting the different iio device modes.
It is currently not being used in this way. Replace the lock with
an internal lock specifically used for protecting the SPI transfer
buffer.

Signed-off-by: default avatarJustin Chen <justinpopo6@gmail.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent be35d281
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+15 −4
Original line number Diff line number Diff line
@@ -56,6 +56,9 @@ struct ti_ads7950_state {
	struct spi_message	ring_msg;
	struct spi_message	scan_single_msg;

	/* Lock to protect the spi xfer buffers */
	struct mutex		slock;

	struct regulator	*reg;
	unsigned int		vref_mv;

@@ -268,6 +271,7 @@ static irqreturn_t ti_ads7950_trigger_handler(int irq, void *p)
	struct ti_ads7950_state *st = iio_priv(indio_dev);
	int ret;

	mutex_lock(&st->slock);
	ret = spi_sync(st->spi, &st->ring_msg);
	if (ret < 0)
		goto out;
@@ -276,6 +280,7 @@ static irqreturn_t ti_ads7950_trigger_handler(int irq, void *p)
					   iio_get_time_ns(indio_dev));

out:
	mutex_unlock(&st->slock);
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
@@ -286,7 +291,7 @@ static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
	struct ti_ads7950_state *st = iio_priv(indio_dev);
	int ret, cmd;

	mutex_lock(&indio_dev->mlock);
	mutex_lock(&st->slock);

	cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(ch) | st->settings;
	st->single_tx = cmd;
@@ -298,7 +303,7 @@ static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
	ret = st->single_rx;

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

	return ret;
}
@@ -432,16 +437,19 @@ static int ti_ads7950_probe(struct spi_device *spi)
	if (ACPI_COMPANION(&spi->dev))
		st->vref_mv = TI_ADS7950_VA_MV_ACPI_DEFAULT;

	mutex_init(&st->slock);

	st->reg = devm_regulator_get(&spi->dev, "vref");
	if (IS_ERR(st->reg)) {
		dev_err(&spi->dev, "Failed get get regulator \"vref\"\n");
		return PTR_ERR(st->reg);
		ret = PTR_ERR(st->reg);
		goto error_destroy_mutex;
	}

	ret = regulator_enable(st->reg);
	if (ret) {
		dev_err(&spi->dev, "Failed to enable regulator \"vref\"\n");
		return ret;
		goto error_destroy_mutex;
	}

	ret = iio_triggered_buffer_setup(indio_dev, NULL,
@@ -463,6 +471,8 @@ error_cleanup_ring:
	iio_triggered_buffer_cleanup(indio_dev);
error_disable_reg:
	regulator_disable(st->reg);
error_destroy_mutex:
	mutex_destroy(&st->slock);

	return ret;
}
@@ -475,6 +485,7 @@ static int ti_ads7950_remove(struct spi_device *spi)
	iio_device_unregister(indio_dev);
	iio_triggered_buffer_cleanup(indio_dev);
	regulator_disable(st->reg);
	mutex_destroy(&st->slock);

	return 0;
}