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path: root/drivers/iio/adc/lpc32xx_adc.c
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Diffstat (limited to 'drivers/iio/adc/lpc32xx_adc.c')
-rw-r--r--drivers/iio/adc/lpc32xx_adc.c11
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/iio/adc/lpc32xx_adc.c b/drivers/iio/adc/lpc32xx_adc.c
index b56ce15255cf..732c924a976d 100644
--- a/drivers/iio/adc/lpc32xx_adc.c
+++ b/drivers/iio/adc/lpc32xx_adc.c
@@ -15,6 +15,7 @@
#include <linux/io.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
@@ -49,6 +50,8 @@ struct lpc32xx_adc_state {
struct clk *clk;
struct completion completion;
struct regulator *vref;
+ /* lock to protect against multiple access to the device */
+ struct mutex lock;
u32 value;
};
@@ -64,10 +67,10 @@ static int lpc32xx_read_raw(struct iio_dev *indio_dev,
switch (mask) {
case IIO_CHAN_INFO_RAW:
- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
ret = clk_prepare_enable(st->clk);
if (ret) {
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);
return ret;
}
/* Measurement setup */
@@ -80,7 +83,7 @@ static int lpc32xx_read_raw(struct iio_dev *indio_dev,
wait_for_completion(&st->completion); /* set by ISR */
clk_disable_unprepare(st->clk);
*val = st->value;
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);
return IIO_VAL_INT;
@@ -201,6 +204,8 @@ static int lpc32xx_adc_probe(struct platform_device *pdev)
iodev->modes = INDIO_DIRECT_MODE;
iodev->num_channels = ARRAY_SIZE(lpc32xx_adc_iio_channels);
+ mutex_init(&st->lock);
+
retval = devm_iio_device_register(&pdev->dev, iodev);
if (retval)
return retval;