staging: comedi: addi_apci_3xxx: remove 'i_NbrAiChannelDiff' boardinfo

The number of differential analog input channels is always half the
number of single-ended channels, 'ai_n_chan', or all the channels
if the board does not support single-ended channels. We can use the
'ai_subdev_flags' boardinfo to determine if the board does not support
single-ended channels.

To simplify the boardinfo, remove the 'i_NbrAiChannelDiff' and just
use 'ai_n_chan' to specify the number of channels.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/addi_apci_3xxx.c

@@ -83,7 +83,6 @@ struct apci3xxx_boardinfo {
 	const char *name;
 	int ai_subdev_flags;
 	int ai_n_chan;
-	int i_NbrAiChannelDiff;
 	unsigned int ai_maxdata;
 	unsigned char ai_conv_units;
 	unsigned int ai_min_acq_ns;
@@ -98,7 +97,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3000-16",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -108,7 +106,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3000-8",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -118,7 +115,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3000-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 4,
-		.i_NbrAiChannelDiff	= 2,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -128,7 +124,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3006-16",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -138,7 +133,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3006-8",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -148,7 +142,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3006-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 4,
-		.i_NbrAiChannelDiff	= 2,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -158,7 +151,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3010-16",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -170,7 +162,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3010-8",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -182,7 +173,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3010-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 4,
-		.i_NbrAiChannelDiff	= 2,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -194,7 +184,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3016-16",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -206,7 +195,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3016-8",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -218,7 +206,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3016-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 4,
-		.i_NbrAiChannelDiff	= 2,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -230,7 +217,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3100-16-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -241,7 +227,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3100-8-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -252,7 +237,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3106-16-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -263,7 +247,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3106-8-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 10000,
@@ -274,7 +257,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3110-16-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -287,7 +269,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3110-8-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0x0fff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -300,7 +281,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3116-16-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 16,
-		.i_NbrAiChannelDiff	= 8,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -313,7 +293,6 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 		.name			= "apci3116-8-4",
 		.ai_subdev_flags	= SDF_COMMON | SDF_GROUND | SDF_DIFF,
 		.ai_n_chan		= 8,
-		.i_NbrAiChannelDiff	= 4,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -325,7 +304,7 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 	[BOARD_APCI3003] = {
 		.name			= "apci3003",
 		.ai_subdev_flags	= SDF_DIFF,
-		.i_NbrAiChannelDiff	= 4,
+		.ai_n_chan		= 4,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US |
 					  CONV_UNIT_NS,
@@ -336,7 +315,7 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 	[BOARD_APCI3002_16] = {
 		.name			= "apci3002-16",
 		.ai_subdev_flags	= SDF_DIFF,
-		.i_NbrAiChannelDiff	= 16,
+		.ai_n_chan		= 16,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -346,7 +325,7 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 	[BOARD_APCI3002_8] = {
 		.name			= "apci3002-8",
 		.ai_subdev_flags	= SDF_DIFF,
-		.i_NbrAiChannelDiff	= 8,
+		.ai_n_chan		= 8,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -356,7 +335,7 @@ static const struct apci3xxx_boardinfo apci3xxx_boardtypes[] = {
 	[BOARD_APCI3002_4] = {
 		.name			= "apci3002-4",
 		.ai_subdev_flags	= SDF_DIFF,
-		.i_NbrAiChannelDiff	= 4,
+		.ai_n_chan		= 4,
 		.ai_maxdata		= 0xffff,
 		.ai_conv_units		= CONV_UNIT_MS | CONV_UNIT_US,
 		.ai_min_acq_ns		= 5000,
@@ -621,24 +600,20 @@ static int apci3xxx_auto_attach(struct comedi_device *dev,
 
 	/*  Allocate and Initialise AI Subdevice Structures */
 	s = &dev->subdevices[0];
-	if (board->ai_n_chan || board->i_NbrAiChannelDiff) {
+	if (board->ai_n_chan) {
 		dev->read_subdev = s;
 		s->type = COMEDI_SUBD_AI;
 		s->subdev_flags = SDF_READABLE | board->ai_subdev_flags;
-		if (board->ai_n_chan) {
-			s->n_chan = board->ai_n_chan;
-			devpriv->b_SingelDiff = 0;
-		} else {
-			s->n_chan = board->i_NbrAiChannelDiff;
-			devpriv->b_SingelDiff = 1;
-		}
+		s->n_chan = board->ai_n_chan;
 		s->maxdata = board->ai_maxdata;
 		s->len_chanlist = s->n_chan;
 		s->range_table = &apci3xxx_ai_range;
-
 		s->insn_config = apci3xxx_ai_insn_config;
 		s->insn_read = apci3xxx_ai_insn_read;
 
+		if ((board->ai_subdev_flags & (SDF_COMMON | SDF_GROUND)) == 0)
+			devpriv->b_SingelDiff = 1;
+
 	} else {
 		s->type = COMEDI_SUBD_UNUSED;
 	}