Richard Weinberger schrieb am 03.12.2014 um 00:32: > Make sure that the read function is not interrupted... There is already a mutex iio_dev->info_exist_lock used to serialize iio_channel_read(), which in turn accesses _read_raw(). See [1].
[1]http://lxr.free-electrons.com/ident?i=iio_channel_read > > Signed-off-by: Richard Weinberger <[email protected]> > --- > drivers/iio/humidity/dht11.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/iio/humidity/dht11.c b/drivers/iio/humidity/dht11.c > index d8771f5..168ebc4 100644 > --- a/drivers/iio/humidity/dht11.c > +++ b/drivers/iio/humidity/dht11.c > @@ -29,6 +29,7 @@ > #include <linux/wait.h> > #include <linux/bitops.h> > #include <linux/completion.h> > +#include <linux/mutex.h> > #include <linux/delay.h> > #include <linux/gpio.h> > #include <linux/of_gpio.h> > @@ -57,6 +58,7 @@ struct dht11 { > int irq; > > struct completion completion; > + struct mutex lock; > > s64 timestamp; > int temperature; > @@ -145,6 +147,7 @@ static int dht11_read_raw(struct iio_dev *iio_dev, > struct dht11 *dht11 = iio_priv(iio_dev); > int ret; > > + mutex_lock(&dht11->lock); > if (dht11->timestamp + DHT11_DATA_VALID_TIME < iio_get_time_ns()) { > reinit_completion(&dht11->completion); > > @@ -185,6 +188,7 @@ static int dht11_read_raw(struct iio_dev *iio_dev, > ret = -EINVAL; > err: > dht11->num_edges = -1; > + mutex_unlock(&dht11->lock); > return ret; > } > > @@ -268,6 +272,7 @@ static int dht11_probe(struct platform_device *pdev) > platform_set_drvdata(pdev, iio); > > init_completion(&dht11->completion); > + mutex_init(&dht11->lock); > iio->name = pdev->name; > iio->dev.parent = &pdev->dev; > iio->info = &dht11_iio_info; > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
