diff --git a/drivers/staging/comedi/drivers/das1800.c b/drivers/staging/comedi/drivers/das1800.c
index e24d0c9ca13a..6795f3e03d1a 100644
--- a/drivers/staging/comedi/drivers/das1800.c
+++ b/drivers/staging/comedi/drivers/das1800.c
@@ -229,7 +229,6 @@ struct das1800_board {
 	int ai_speed;		/* max conversion period in nanoseconds */
 	int resolution;		/* bits of ai resolution */
 	int qram_len;		/* length of card's channel / gain queue */
-	int common;		/* supports AREF_COMMON flag */
 	int do_n_chan;		/* number of digital output channels */
 	int ao_ability;		/* 0 == no analog out, 1 == basic analog out, 2 == waveform analog out */
 	int ao_n_chan;		/* number of analog out channels */
@@ -247,7 +246,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 6250,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 0,
 		.ao_n_chan	= 0,
@@ -259,7 +257,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 6250,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 1,
 		.ao_n_chan	= 4,
@@ -271,7 +268,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 6250,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 0,
 		.ao_n_chan	= 0,
@@ -283,7 +279,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 6250,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 1,
 		.ao_n_chan	= 4,
@@ -295,7 +290,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 20000,
 		.resolution	= 16,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 0,
 		.ao_n_chan	= 0,
@@ -307,7 +301,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 20000,
 		.resolution	= 16,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 1,
 		.ao_n_chan	= 2,
@@ -319,7 +312,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 6250,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 2,
 		.ao_n_chan	= 2,
@@ -331,7 +323,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 6250,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 2,
 		.ao_n_chan	= 2,
@@ -343,7 +334,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 0,
 		.ao_n_chan	= 0,
@@ -355,7 +345,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 1,
 		.ao_n_chan	= 4,
@@ -367,7 +356,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 0,
 		.ao_n_chan	= 0,
@@ -379,7 +367,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 1,
 		.ao_n_chan	= 4,
@@ -391,7 +378,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 10000,
 		.resolution	= 16,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 0,
 		.ao_n_chan	= 0,
@@ -403,7 +389,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 10000,
 		.resolution	= 16,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 1,
 		.ao_n_chan	= 2,
@@ -415,7 +400,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 64,
-		.common		= 0,
 		.do_n_chan	= 8,
 		.ao_ability	= 1,
 		.ao_n_chan	= 2,
@@ -427,7 +411,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 64,
-		.common		= 0,
 		.do_n_chan	= 8,
 		.ao_ability	= 1,
 		.ao_n_chan	= 2,
@@ -439,7 +422,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 2,
 		.ao_n_chan	= 2,
@@ -451,7 +433,6 @@ static const struct das1800_board das1800_boards[] = {
 		.ai_speed	= 3000,
 		.resolution	= 12,
 		.qram_len	= 256,
-		.common		= 1,
 		.do_n_chan	= 4,
 		.ao_ability	= 2,
 		.ao_n_chan	= 2,
@@ -1394,7 +1375,7 @@ static int das1800_attach(struct comedi_device *dev,
 	s = &dev->subdevices[0];
 	s->type		= COMEDI_SUBD_AI;
 	s->subdev_flags	= SDF_READABLE | SDF_DIFF | SDF_GROUND;
-	if (board->common)
+	if (board->id != DAS1800_ID_HC)
 		s->subdev_flags	|= SDF_COMMON;
 	s->n_chan	= board->qram_len;
 	s->maxdata	= (1 << board->resolution) - 1;