diff options
Diffstat (limited to 'drivers/iio/adc/lpc32xx_adc.c')
-rw-r--r-- | drivers/iio/adc/lpc32xx_adc.c | 11 |
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; |