[PATCH 4/6] staging: comedi: addi_apci_1564: add a subdevice for Change-of-State interrupt support

[Chase Southwood <chase.southwood@gmail.com>]

This board supports an interrupt that can be generated by an AND/OR
combination of 16 of the input channels.

Create a separate subdevice to handle this interrupt.

Signed-off-by: Chase Southwood <chase.southwood@gmail.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
---
 drivers/staging/comedi/drivers/addi_apci_1564.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/comedi/drivers/addi_apci_1564.c b/drivers/staging/comedi/drivers/addi_apci_1564.c
index 5901143..183fdc3 100644
--- a/drivers/staging/comedi/drivers/addi_apci_1564.c
+++ b/drivers/staging/comedi/drivers/addi_apci_1564.c
@@ -105,7 +105,7 @@ static int apci1564_auto_attach(struct comedi_device *dev,
 			dev->irq = pcidev->irq;
 	}
 
-	ret = comedi_alloc_subdevices(dev, 3);
+	ret = comedi_alloc_subdevices(dev, 4);
 	if (ret)
 		return ret;
 
@@ -144,6 +144,20 @@ static int apci1564_auto_attach(struct comedi_device *dev,
 	s->insn_read = apci1564_timer_read;
 	s->insn_config = apci1564_timer_config;
 
+	/* Change-Of-State (COS) interrupt subdevice */
+	s = &dev->subdevices[3];
+	if (dev->irq) {
+		dev->read_subdev = s;
+		s->type = COMEDI_SUBD_DI;
+		s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
+		s->n_chan = 1;
+		s->maxdata = 1;
+		s->range_table = &range_digital;
+		s->len_chanlist = 1;
+	} else {
+		s->type = COMEDI_SUBD_UNUSED;
+	}
+
 	return 0;
 }
 
-- 
1.9.3