+ return 0;
+}
+
+static int ni_ao_insn_config(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn, unsigned int *data)
+{
+ const struct ni_board_struct *board = dev->board_ptr;
+ struct ni_private *devpriv = dev->private;
+ unsigned int nbytes;
+
+ switch (data[0]) {
+ case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE:
+ switch (data[1]) {
+ case COMEDI_OUTPUT:
+ nbytes = comedi_samples_to_bytes(s,
+ board->ao_fifo_depth);
+ data[2] = 1 + nbytes;
+ if (devpriv->mite)
+ data[2] += devpriv->mite->fifo_size;
+ break;
+ case COMEDI_INPUT:
+ data[2] = 0;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+ case INSN_CONFIG_ARM:
+ return ni_ao_arm(dev, s);
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static int ni_ao_inttrig(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ unsigned int trig_num)
+{
+ struct ni_private *devpriv = dev->private;
+ struct comedi_cmd *cmd = &s->async->cmd;
+ int ret;
+
+ /*
+ * Require trig_num == cmd->start_arg when cmd->start_src == TRIG_INT.
+ * For backwards compatibility, also allow trig_num == 0 when
+ * cmd->start_src != TRIG_INT (i.e. when cmd->start_src == TRIG_EXT);
+ * in that case, the internal trigger is being used as a pre-trigger
+ * before the external trigger.
+ */
+ if (!(trig_num == cmd->start_arg ||
+ (trig_num == 0 && cmd->start_src != TRIG_INT)))
+ return -EINVAL;
+
+ /*
+ * Null trig at beginning prevent ao start trigger from executing more
+ * than once per command.
+ */
+ s->async->inttrig = NULL;
+
+ if (devpriv->ao_needs_arming) {
+ /* only arm this device if it still needs arming */
+ ret = ni_ao_arm(dev, s);
+ if (ret)
+ return ret;
+ }
+