[v4,08/12] eventdev: improve doxygen comments for control APIs

The doxygen comments for the port attributes, start and stop (and
related functions) are improved.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

---
V3: add missing "." on end of sentences/lines.
---
 lib/eventdev/rte_eventdev.h | 47 +++++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 18 deletions(-)
  

> The doxygen comments for the port attributes, start and stop (and
> related functions) are improved.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Acked-by: Pavan Nikhilesh <pbhagavatula@marvell.com>

> 
> ---
> V3: add missing "." on end of sentences/lines.
> ---
>  lib/eventdev/rte_eventdev.h | 47 +++++++++++++++++++++++--------------
>  1 file changed, 29 insertions(+), 18 deletions(-)
> 
> diff --git a/lib/eventdev/rte_eventdev.h b/lib/eventdev/rte_eventdev.h
> index e38354cedd..72814719b2 100644
> --- a/lib/eventdev/rte_eventdev.h
> +++ b/lib/eventdev/rte_eventdev.h
> @@ -1201,19 +1201,21 @@ rte_event_port_quiesce(uint8_t dev_id, uint8_t
> port_id,
>  		       rte_eventdev_port_flush_t release_cb, void *args);
> 
>  /**
> - * The queue depth of the port on the enqueue side
> + * Port attribute id for the maximum size of a burst enqueue operation
> supported on a port.
>   */
>  #define RTE_EVENT_PORT_ATTR_ENQ_DEPTH 0
>  /**
> - * The queue depth of the port on the dequeue side
> + * Port attribute id for the maximum size of a dequeue burst which can be
> returned from a port.
>   */
>  #define RTE_EVENT_PORT_ATTR_DEQ_DEPTH 1
>  /**
> - * The new event threshold of the port
> + * Port attribute id for the new event threshold of the port.
> + * Once the number of events in the system exceeds this threshold, the
> enqueue of NEW-type
> + * events will fail.
>   */
>  #define RTE_EVENT_PORT_ATTR_NEW_EVENT_THRESHOLD 2
>  /**
> - * The implicit release disable attribute of the port
> + * Port attribute id for the implicit release disable attribute of the port.
>   */
>  #define RTE_EVENT_PORT_ATTR_IMPLICIT_RELEASE_DISABLE 3
> 
> @@ -1221,17 +1223,18 @@ rte_event_port_quiesce(uint8_t dev_id, uint8_t
> port_id,
>   * Get an attribute from a port.
>   *
>   * @param dev_id
> - *   Eventdev id
> + *   The identifier of the device.
>   * @param port_id
> - *   Eventdev port id
> + *   The index of the event port to query. The value must be less than
> + *   @ref rte_event_dev_config.nb_event_ports previously supplied to
> rte_event_dev_configure().
>   * @param attr_id
> - *   The attribute ID to retrieve
> + *   The attribute ID to retrieve (RTE_EVENT_PORT_ATTR_*)
>   * @param[out] attr_value
>   *   A pointer that will be filled in with the attribute value if successful
>   *
>   * @return
> - *   - 0: Successfully returned value
> - *   - (-EINVAL) Invalid device, port or attr_id, or attr_value was NULL
> + *   - 0: Successfully returned value.
> + *   - (-EINVAL) Invalid device, port or attr_id, or attr_value was NULL.
>   */
>  int
>  rte_event_port_attr_get(uint8_t dev_id, uint8_t port_id, uint32_t attr_id,
> @@ -1240,17 +1243,19 @@ rte_event_port_attr_get(uint8_t dev_id, uint8_t
> port_id, uint32_t attr_id,
>  /**
>   * Start an event device.
>   *
> - * The device start step is the last one and consists of setting the event
> - * queues to start accepting the events and schedules to event ports.
> + * The device start step is the last one in device setup, and enables the event
> + * ports and queues to start accepting events and scheduling them to event
> ports.
>   *
>   * On success, all basic functions exported by the API (event enqueue,
>   * event dequeue and so on) can be invoked.
>   *
>   * @param dev_id
> - *   Event device identifier
> + *   Event device identifier.
>   * @return
>   *   - 0: Success, device started.
> - *   - -ESTALE : Not all ports of the device are configured
> + *   - -EINVAL:  Invalid device id provided.
> + *   - -ENOTSUP: Device does not support this operation.
> + *   - -ESTALE : Not all ports of the device are configured.
>   *   - -ENOLINK: Not all queues are linked, which could lead to deadlock.
>   */
>  int
> @@ -1292,18 +1297,22 @@ typedef void
> (*rte_eventdev_stop_flush_t)(uint8_t dev_id,
>   * callback function must be registered in every process that can call
>   * rte_event_dev_stop().
>   *
> + * Only one callback function may be registered. Each new call replaces
> + * the existing registered callback function with the new function passed in.
> + *
>   * To unregister a callback, call this function with a NULL callback pointer.
>   *
>   * @param dev_id
>   *   The identifier of the device.
>   * @param callback
> - *   Callback function invoked once per flushed event.
> + *   Callback function to be invoked once per flushed event.
> + *   Pass NULL to unset any previously-registered callback function.
>   * @param userdata
>   *   Argument supplied to callback.
>   *
>   * @return
>   *  - 0 on success.
> - *  - -EINVAL if *dev_id* is invalid
> + *  - -EINVAL if *dev_id* is invalid.
>   *
>   * @see rte_event_dev_stop()
>   */
> @@ -1314,12 +1323,14 @@ int
> rte_event_dev_stop_flush_callback_register(uint8_t dev_id,
>   * Close an event device. The device cannot be restarted!
>   *
>   * @param dev_id
> - *   Event device identifier
> + *   Event device identifier.
>   *
>   * @return
>   *  - 0 on successfully closing device
> - *  - <0 on failure to close device
> - *  - (-EAGAIN) if device is busy
> + *  - <0 on failure to close device.
> + *    - -EINVAL - invalid device id.
> + *    - -ENOTSUP - operation not supported for this device.
> + *    - -EAGAIN - device is busy.
>   */
>  int
>  rte_event_dev_close(uint8_t dev_id);
> --
> 2.40.1