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Diffstat (limited to 'kernel/drivers/iio/industrialio-trigger.c')
-rw-r--r--kernel/drivers/iio/industrialio-trigger.c39
1 files changed, 34 insertions, 5 deletions
diff --git a/kernel/drivers/iio/industrialio-trigger.c b/kernel/drivers/iio/industrialio-trigger.c
index d31098e0c..ae2806aaf 100644
--- a/kernel/drivers/iio/industrialio-trigger.c
+++ b/kernel/drivers/iio/industrialio-trigger.c
@@ -40,7 +40,14 @@ static DEFINE_MUTEX(iio_trigger_list_lock);
/**
* iio_trigger_read_name() - retrieve useful identifying name
- **/
+ * @dev: device associated with the iio_trigger
+ * @attr: pointer to the device_attribute structure that is
+ * being processed
+ * @buf: buffer to print the name into
+ *
+ * Return: a negative number on failure or the number of written
+ * characters on success.
+ */
static ssize_t iio_trigger_read_name(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -288,10 +295,17 @@ EXPORT_SYMBOL_GPL(iio_dealloc_pollfunc);
/**
* iio_trigger_read_current() - trigger consumer sysfs query current trigger
+ * @dev: device associated with an industrial I/O device
+ * @attr: pointer to the device_attribute structure that
+ * is being processed
+ * @buf: buffer where the current trigger name will be printed into
*
* For trigger consumers the current_trigger interface allows the trigger
* used by the device to be queried.
- **/
+ *
+ * Return: a negative number on failure, the number of characters written
+ * on success or 0 if no trigger is available
+ */
static ssize_t iio_trigger_read_current(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -305,11 +319,18 @@ static ssize_t iio_trigger_read_current(struct device *dev,
/**
* iio_trigger_write_current() - trigger consumer sysfs set current trigger
+ * @dev: device associated with an industrial I/O device
+ * @attr: device attribute that is being processed
+ * @buf: string buffer that holds the name of the trigger
+ * @len: length of the trigger name held by buf
*
* For trigger consumers the current_trigger interface allows the trigger
* used for this device to be specified at run time based on the trigger's
* name.
- **/
+ *
+ * Return: negative error code on failure or length of the buffer
+ * on success
+ */
static ssize_t iio_trigger_write_current(struct device *dev,
struct device_attribute *attr,
const char *buf,
@@ -345,10 +366,18 @@ static ssize_t iio_trigger_write_current(struct device *dev,
indio_dev->trig = trig;
- if (oldtrig)
+ if (oldtrig) {
+ if (indio_dev->modes & INDIO_EVENT_TRIGGERED)
+ iio_trigger_detach_poll_func(oldtrig,
+ indio_dev->pollfunc_event);
iio_trigger_put(oldtrig);
- if (indio_dev->trig)
+ }
+ if (indio_dev->trig) {
iio_trigger_get(indio_dev->trig);
+ if (indio_dev->modes & INDIO_EVENT_TRIGGERED)
+ iio_trigger_attach_poll_func(indio_dev->trig,
+ indio_dev->pollfunc_event);
+ }
return len;
}