/**
* struct mbox_controller - Controller of a class of communication channels
- * @dev: Device backing this controller
- * @ops: Operators that work on each communication chan
- * @chans: Array of channels
- * @num_chans: Number of channels in the 'chans' array.
+ * @dev: Device backing this controller. Required.
+ * @ops: Operators that work on each communication chan. Required.
+ * @chans: Array of channels. Required.
+ * @num_chans: Number of channels in the 'chans' array. Required.
* @txdone_irq: Indicates if the controller can report to API when
* the last transmitted data was read by the remote.
* Eg, if it has some TX ACK irq.
* @of_xlate: Controller driver specific mapping of channel via DT
* @poll_hrt: API private. hrtimer used to poll for TXDONE on all
* channels.
+ * @poll_hrt_lock: API private. Lock protecting access to poll_hrt.
* @node: API private. To hook into list of controllers.
*/
struct mbox_controller {