[PATCH v3 4/8] iio: adc: max1027: Prepare the introduction of different resolutions

Miquel Raynal
2019-10-07T13:27:27Z

Maxim's max1027/29/31 series returns the measured voltages with a
resolution of 10 bits. There is a very similar series, max1227/29/31
which works identically but uses a resolution of 12 bits. Prepare the
support for these chips by turning the 'depth' into a macro parameter
instead of hardcoding it everywhere. Also reorganize just a bit the
macros at the top to avoid repeating tens of lines when adding support
for a new chip.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
drivers/iio/adc/max1027.c | 74 +++++++++++++++++----------------------
1 file changed, 32 insertions(+), 42 deletions(-)

diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
index f9b473ee6711..8b449044bef5 100644
--- a/drivers/iio/adc/max1027.c
+++ b/drivers/iio/adc/max1027.c
@@ -83,7 +83,7 @@ static const struct of_device_id max1027_adc_dt_ids[] = {
MODULE_DEVICE_TABLE(of, max1027_adc_dt_ids);
#endif

-#define MAX1027_V_CHAN(index) \
+#define MAX1027_V_CHAN(index, depth) \
{ \
.type = IIO_VOLTAGE, \
.indexed = 1, \
@@ -93,7 +93,7 @@ MODULE_DEVICE_TABLE(of, max1027_adc_dt_ids);
.scan_index = index + 1, \
.scan_type = { \
.sign = 'u', \
- .realbits = 10, \
+ .realbits = depth, \
.storagebits = 16, \
.shift = 2, \
.endianness = IIO_BE, \
@@ -115,52 +115,42 @@ MODULE_DEVICE_TABLE(of, max1027_adc_dt_ids);
}, \
}

+#define MAX1X27_CHANNELS(depth) \
+ MAX1027_T_CHAN, \
+ MAX1027_V_CHAN(0, depth), \
+ MAX1027_V_CHAN(1, depth), \
+ MAX1027_V_CHAN(2, depth), \
+ MAX1027_V_CHAN(3, depth), \
+ MAX1027_V_CHAN(4, depth), \
+ MAX1027_V_CHAN(5, depth), \
+ MAX1027_V_CHAN(6, depth), \
+ MAX1027_V_CHAN(7, depth)
+
+#define MAX1X29_CHANNELS(depth) \
+ MAX1X27_CHANNELS(depth), \
+ MAX1027_V_CHAN(8, depth), \
+ MAX1027_V_CHAN(9, depth), \
+ MAX1027_V_CHAN(10, depth), \
+ MAX1027_V_CHAN(11, depth)
+
+#define MAX1X31_CHANNELS(depth) \
+ MAX1X27_CHANNELS(depth), \
+ MAX1X29_CHANNELS(depth), \
+ MAX1027_V_CHAN(12, depth), \
+ MAX1027_V_CHAN(13, depth), \
+ MAX1027_V_CHAN(14, depth), \
+ MAX1027_V_CHAN(15, depth)
+
static const struct iio_chan_spec max1027_channels[] = {
- MAX1027_T_CHAN,
- MAX1027_V_CHAN(0),
- MAX1027_V_CHAN(1),
- MAX1027_V_CHAN(2),
- MAX1027_V_CHAN(3),
- MAX1027_V_CHAN(4),
- MAX1027_V_CHAN(5),
- MAX1027_V_CHAN(6),
- MAX1027_V_CHAN(7)
+ MAX1X27_CHANNELS(10),
};

static const struct iio_chan_spec max1029_channels[] = {
- MAX1027_T_CHAN,
- MAX1027_V_CHAN(0),
- MAX1027_V_CHAN(1),
- MAX1027_V_CHAN(2),
- MAX1027_V_CHAN(3),
- MAX1027_V_CHAN(4),
- MAX1027_V_CHAN(5),
- MAX1027_V_CHAN(6),
- MAX1027_V_CHAN(7),
- MAX1027_V_CHAN(8),
- MAX1027_V_CHAN(9),
- MAX1027_V_CHAN(10),
- MAX1027_V_CHAN(11)
+ MAX1X29_CHANNELS(10),
};

static const struct iio_chan_spec max1031_channels[] = {
- MAX1027_T_CHAN,
- MAX1027_V_CHAN(0),
- MAX1027_V_CHAN(1),
- MAX1027_V_CHAN(2),
- MAX1027_V_CHAN(3),
- MAX1027_V_CHAN(4),
- MAX1027_V_CHAN(5),
- MAX1027_V_CHAN(6),
- MAX1027_V_CHAN(7),
- MAX1027_V_CHAN(8),
- MAX1027_V_CHAN(9),
- MAX1027_V_CHAN(10),
- MAX1027_V_CHAN(11),
- MAX1027_V_CHAN(12),
- MAX1027_V_CHAN(13),
- MAX1027_V_CHAN(14),
- MAX1027_V_CHAN(15)
+ MAX1X31_CHANNELS(10),
};

static const unsigned long max1027_available_scan_masks[] = {
@@ -284,7 +274,7 @@ static int max1027_read_raw(struct iio_dev *indio_dev,
break;
case IIO_VOLTAGE:
*val = 2500;
- *val2 = 10;
+ *val2 = chan->scan_type.realbits;
ret = IIO_VAL_FRACTIONAL_LOG2;
break;
default:
--
2.20.1