staging: comedi: das1800: refactor 'range_ai' boardinfo

The boards supported by this driver have analog inputs with gains
of 1, 10, 50, and 250 ("01" type) or 1, 2, 4, and 8 ("02" type).
Unfortunately, the "01"/"02" type cannot be determined from the
boards id or by probing.

Replace the 'range_ai' member of the boardinfo with a bit-field flag,
'is_01_series' and only set it for the "01" type boards. Remove the
unnecessary initialization for the "02" type boards.

For aesthetics, rename the comedi_lrange arrays and document the gain.

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>

diff --git a/drivers/staging/comedi/drivers/das1800.c b/drivers/staging/comedi/drivers/das1800.c
index 5d40811..3280763 100644 (file)
--- a/drivers/staging/comedi/drivers/das1800.c
+++ b/drivers/staging/comedi/drivers/das1800.c
@@ -167,30 +167,29 @@ TODO:
 
 #define IOBASE2                   0x400        /* offset of additional ioports used on 'ao' cards */
 
-/* analog input ranges */
-static const struct comedi_lrange range_ai_das1801 = {
+static const struct comedi_lrange das1801_ai_range = {
        8, {
-               BIP_RANGE(5),
-               BIP_RANGE(1),
-               BIP_RANGE(0.1),
-               BIP_RANGE(0.02),
-               UNI_RANGE(5),
-               UNI_RANGE(1),
-               UNI_RANGE(0.1),
-               UNI_RANGE(0.02)
+               BIP_RANGE(5),           /* bipolar gain = 1 */
+               BIP_RANGE(1),           /* bipolar gain = 10 */
+               BIP_RANGE(0.1),         /* bipolar gain = 50 */
+               BIP_RANGE(0.02),        /* bipolar gain = 250 */
+               UNI_RANGE(5),           /* unipolar gain = 1 */
+               UNI_RANGE(1),           /* unipolar gain = 10 */
+               UNI_RANGE(0.1),         /* unipolar gain = 50 */
+               UNI_RANGE(0.02)         /* unipolar gain = 250 */
        }
 };
 
-static const struct comedi_lrange range_ai_das1802 = {
+static const struct comedi_lrange das1802_ai_range = {
        8, {
-               BIP_RANGE(10),
-               BIP_RANGE(5),
-               BIP_RANGE(2.5),
-               BIP_RANGE(1.25),
-               UNI_RANGE(10),
-               UNI_RANGE(5),
-               UNI_RANGE(2.5),
-               UNI_RANGE(1.25)
+               BIP_RANGE(10),          /* bipolar gain = 1 */
+               BIP_RANGE(5),           /* bipolar gain = 2 */
+               BIP_RANGE(2.5),         /* bipolar gain = 4 */
+               BIP_RANGE(1.25),        /* bipolar gain = 8 */
+               UNI_RANGE(10),          /* unipolar gain = 1 */
+               UNI_RANGE(5),           /* unipolar gain = 2 */
+               UNI_RANGE(2.5),         /* unipolar gain = 4 */
+               UNI_RANGE(1.25)         /* unipolar gain = 8 */
        }
 };
 
@@ -228,7 +227,7 @@ struct das1800_board {
        unsigned char id;
        int ai_speed;           /* max conversion period in nanoseconds */
        int qram_len;           /* length of card's channel / gain queue */
-       const struct comedi_lrange *range_ai;   /* available input ranges */
+       unsigned int is_01_series:1;
 };
 
 /* Warning: the maximum conversion speeds listed below are
@@ -241,126 +240,115 @@ static const struct das1800_board das1800_boards[] = {
                .id             = DAS1800_ID_ST,
                .ai_speed       = 6250,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1701ST_DA] = {
                .name           = "das-1701st-da",
                .id             = DAS1800_ID_ST_DA,
                .ai_speed       = 6250,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1702ST] = {
                .name           = "das-1702st",
                .id             = DAS1800_ID_ST,
                .ai_speed       = 6250,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1702ST_DA] = {
                .name           = "das-1702st-da",
                .id             = DAS1800_ID_ST_DA,
                .ai_speed       = 6250,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1702HR] = {
                .name           = "das-1702hr",
                .id             = DAS1800_ID_HR,
                .ai_speed       = 20000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1702HR_DA] = {
                .name           = "das-1702hr-da",
                .id             = DAS1800_ID_HR_DA,
                .ai_speed       = 20000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1701AO] = {
                .name           = "das-1701ao",
                .id             = DAS1800_ID_AO,
                .ai_speed       = 6250,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1702AO] = {
                .name           = "das-1702ao",
                .id             = DAS1800_ID_AO,
                .ai_speed       = 6250,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1801ST] = {
                .name           = "das-1801st",
                .id             = DAS1800_ID_ST,
                .ai_speed       = 3000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1801ST_DA] = {
                .name           = "das-1801st-da",
                .id             = DAS1800_ID_ST_DA,
                .ai_speed       = 3000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1802ST] = {
                .name           = "das-1802st",
                .id             = DAS1800_ID_ST,
                .ai_speed       = 3000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1802ST_DA] = {
                .name           = "das-1802st-da",
                .id             = DAS1800_ID_ST_DA,
                .ai_speed       = 3000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1802HR] = {
                .name           = "das-1802hr",
                .id             = DAS1800_ID_HR,
                .ai_speed       = 10000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1802HR_DA] = {
                .name           = "das-1802hr-da",
                .id             = DAS1800_ID_HR_DA,
                .ai_speed       = 10000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1801HC] = {
                .name           = "das-1801hc",
                .id             = DAS1800_ID_HC,
                .ai_speed       = 3000,
                .qram_len       = 64,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1802HC] = {
                .name           = "das-1802hc",
                .id             = DAS1800_ID_HC,
                .ai_speed       = 3000,
                .qram_len       = 64,
-               .range_ai       = &range_ai_das1802,
        },
        [BOARD_DAS1801AO] = {
                .name           = "das-1801ao",
                .id             = DAS1800_ID_AO,
                .ai_speed       = 3000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1801,
+               .is_01_series   = 1,
        },
        [BOARD_DAS1802AO] = {
                .name           = "das-1802ao",
                .id             = DAS1800_ID_AO,
                .ai_speed       = 3000,
                .qram_len       = 256,
-               .range_ai       = &range_ai_das1802,
        },
 };
 
@@ -1312,7 +1300,8 @@ static int das1800_attach(struct comedi_device *dev,
                s->subdev_flags |= SDF_COMMON;
        s->n_chan       = board->qram_len;
        s->maxdata      = is_16bit ? 0xffff : 0x0fff;
-       s->range_table  = board->range_ai;
+       s->range_table  = board->is_01_series ? &das1801_ai_range
+                                             : &das1802_ai_range;
        s->insn_read    = das1800_ai_insn_read;
        if (dev->irq) {
                dev->read_subdev = s;