summaryrefslogtreecommitdiff
path: root/drivers/iio/adc
diff options
context:
space:
mode:
authorJustin Chen <justinpopo6@gmail.com>2019-03-01 01:16:48 +0300
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2019-04-04 22:19:41 +0300
commitabbde2792999c9ad3514dd25d7f8d9a96034fe16 (patch)
treea095942eb1564eab08838b695768564376653d73 /drivers/iio/adc
parentbe35d281da6af5f147383f06d050426901b2d25f (diff)
downloadlinux-abbde2792999c9ad3514dd25d7f8d9a96034fe16.tar.xz
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: Justin Chen <justinpopo6@gmail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio/adc')
-rw-r--r--drivers/iio/adc/ti-ads7950.c19
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c
index 0ad63592cc3c..1e47bef72bb7 100644
--- a/drivers/iio/adc/ti-ads7950.c
+++ b/drivers/iio/adc/ti-ads7950.c
@@ -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;
}