This patch is used to update the documents of D-release.

[kvmfornfv.git] / kernel / drivers / iio / industrialio-trigger.c

diff --git a/kernel/drivers/iio/industrialio-trigger.c b/kernel/drivers/iio/industrialio-trigger.c
index d31098e..0c52dfe 100644 (file)
--- 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)
@@ -203,22 +210,35 @@ static int iio_trigger_attach_poll_func(struct iio_trigger *trig,
 
        /* Prevent the module from being removed whilst attached to a trigger */
        __module_get(pf->indio_dev->info->driver_module);
+
+       /* Get irq number */
        pf->irq = iio_trigger_get_irq(trig);
+       if (pf->irq < 0)
+               goto out_put_module;
+
+       /* Request irq */
        ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
                                   pf->type, pf->name,
                                   pf);
-       if (ret < 0) {
-               module_put(pf->indio_dev->info->driver_module);
-               return ret;
-       }
+       if (ret < 0)
+               goto out_put_irq;
 
+       /* Enable trigger in driver */
        if (trig->ops && trig->ops->set_trigger_state && notinuse) {
                ret = trig->ops->set_trigger_state(trig, true);
                if (ret < 0)
-                       module_put(pf->indio_dev->info->driver_module);
+                       goto out_free_irq;
        }
 
        return ret;
+
+out_free_irq:
+       free_irq(pf->irq, pf);
+out_put_irq:
+       iio_trigger_put_irq(trig, pf->irq);
+out_put_module:
+       module_put(pf->indio_dev->info->driver_module);
+       return ret;
 }
 
 static int iio_trigger_detach_poll_func(struct iio_trigger *trig,
@@ -288,10 +308,17 @@ 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 +332,18 @@ 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 +379,18 @@ 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;
 }