[PATCH 1/7] iio: adc: ad7606: add 'bits' parameter to channels macros

[Alexandru Ardelean <aardelean@baylibre.com>]

There are some newer additions to the AD7606 family, which support 18 bit
precision.
Up until now, all chips were 16 bit.

This change adds a 'bits' parameter to the AD760X_CHANNEL macro and renames
'ad7606_channels' -> 'ad7606_channels_16bit' for the current devices.

The AD7606_CHANNEL_PER_CHAN_SCALE() macro is also introduced, as it will
also require that the number of bits be correctly adjusted (for 18 bit
parts).

Signed-off-by: Alexandru Ardelean <aardelean@baylibre.com>
---
 drivers/iio/adc/ad7606.c     | 58 ++++++++++++++++++------------------
 drivers/iio/adc/ad7606.h     | 18 ++++++-----
 drivers/iio/adc/ad7606_spi.c | 16 +++++-----
 3 files changed, 47 insertions(+), 45 deletions(-)

diff --git a/drivers/iio/adc/ad7606.c b/drivers/iio/adc/ad7606.c
index 539e4a8621fe..dba1f28782e4 100644
--- a/drivers/iio/adc/ad7606.c
+++ b/drivers/iio/adc/ad7606.c
@@ -333,16 +333,16 @@ static const struct iio_chan_spec ad7605_channels[] = {
 	AD7605_CHANNEL(3),
 };
 
-static const struct iio_chan_spec ad7606_channels[] = {
+static const struct iio_chan_spec ad7606_channels_16bit[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(8),
-	AD7606_CHANNEL(0),
-	AD7606_CHANNEL(1),
-	AD7606_CHANNEL(2),
-	AD7606_CHANNEL(3),
-	AD7606_CHANNEL(4),
-	AD7606_CHANNEL(5),
-	AD7606_CHANNEL(6),
-	AD7606_CHANNEL(7),
+	AD7606_CHANNEL(0, 16),
+	AD7606_CHANNEL(1, 16),
+	AD7606_CHANNEL(2, 16),
+	AD7606_CHANNEL(3, 16),
+	AD7606_CHANNEL(4, 16),
+	AD7606_CHANNEL(5, 16),
+	AD7606_CHANNEL(6, 16),
+	AD7606_CHANNEL(7, 16),
 };
 
 /*
@@ -357,22 +357,22 @@ static const struct iio_chan_spec ad7606_channels[] = {
  */
 static const struct iio_chan_spec ad7616_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(16),
-	AD7606_CHANNEL(0),
-	AD7606_CHANNEL(1),
-	AD7606_CHANNEL(2),
-	AD7606_CHANNEL(3),
-	AD7606_CHANNEL(4),
-	AD7606_CHANNEL(5),
-	AD7606_CHANNEL(6),
-	AD7606_CHANNEL(7),
-	AD7606_CHANNEL(8),
-	AD7606_CHANNEL(9),
-	AD7606_CHANNEL(10),
-	AD7606_CHANNEL(11),
-	AD7606_CHANNEL(12),
-	AD7606_CHANNEL(13),
-	AD7606_CHANNEL(14),
-	AD7606_CHANNEL(15),
+	AD7606_CHANNEL(0, 16),
+	AD7606_CHANNEL(1, 16),
+	AD7606_CHANNEL(2, 16),
+	AD7606_CHANNEL(3, 16),
+	AD7606_CHANNEL(4, 16),
+	AD7606_CHANNEL(5, 16),
+	AD7606_CHANNEL(6, 16),
+	AD7606_CHANNEL(7, 16),
+	AD7606_CHANNEL(8, 16),
+	AD7606_CHANNEL(9, 16),
+	AD7606_CHANNEL(10, 16),
+	AD7606_CHANNEL(11, 16),
+	AD7606_CHANNEL(12, 16),
+	AD7606_CHANNEL(13, 16),
+	AD7606_CHANNEL(14, 16),
+	AD7606_CHANNEL(15, 16),
 };
 
 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
@@ -382,25 +382,25 @@ static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
 		.num_channels = 5,
 	},
 	[ID_AD7606_8] = {
-		.channels = ad7606_channels,
+		.channels = ad7606_channels_16bit,
 		.num_channels = 9,
 		.oversampling_avail = ad7606_oversampling_avail,
 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
 	},
 	[ID_AD7606_6] = {
-		.channels = ad7606_channels,
+		.channels = ad7606_channels_16bit,
 		.num_channels = 7,
 		.oversampling_avail = ad7606_oversampling_avail,
 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
 	},
 	[ID_AD7606_4] = {
-		.channels = ad7606_channels,
+		.channels = ad7606_channels_16bit,
 		.num_channels = 5,
 		.oversampling_avail = ad7606_oversampling_avail,
 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
 	},
 	[ID_AD7606B] = {
-		.channels = ad7606_channels,
+		.channels = ad7606_channels_16bit,
 		.num_channels = 9,
 		.oversampling_avail = ad7606_oversampling_avail,
 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
diff --git a/drivers/iio/adc/ad7606.h b/drivers/iio/adc/ad7606.h
index 0c6a88cc4695..771121350f98 100644
--- a/drivers/iio/adc/ad7606.h
+++ b/drivers/iio/adc/ad7606.h
@@ -8,7 +8,7 @@
 #ifndef IIO_ADC_AD7606_H_
 #define IIO_ADC_AD7606_H_
 
-#define AD760X_CHANNEL(num, mask_sep, mask_type, mask_all) {	\
+#define AD760X_CHANNEL(num, mask_sep, mask_type, mask_all, bits) {	\
 		.type = IIO_VOLTAGE,				\
 		.indexed = 1,					\
 		.channel = num,					\
@@ -19,24 +19,26 @@
 		.scan_index = num,				\
 		.scan_type = {					\
 			.sign = 's',				\
-			.realbits = 16,				\
-			.storagebits = 16,			\
+			.realbits = (bits),			\
+			.storagebits = (bits),			\
 			.endianness = IIO_CPU,			\
 		},						\
 }
 
 #define AD7605_CHANNEL(num)				\
 	AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_RAW),	\
-		BIT(IIO_CHAN_INFO_SCALE), 0)
+		BIT(IIO_CHAN_INFO_SCALE), 0, 16)
 
-#define AD7606_CHANNEL(num)				\
+#define AD7606_CHANNEL(num, bits)			\
 	AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_RAW),	\
 		BIT(IIO_CHAN_INFO_SCALE),		\
-		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO))
+		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), bits)
 
-#define AD7616_CHANNEL(num)	\
+#define AD7606_SW_CHANNEL(num, bits)	\
 	AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),\
-		0, BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO))
+		0, BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), bits)
+
+#define AD7616_CHANNEL(num)	AD7606_SW_CHANNEL(num, 16)
 
 /**
  * struct ad7606_chip_info - chip specific information
diff --git a/drivers/iio/adc/ad7606_spi.c b/drivers/iio/adc/ad7606_spi.c
index 287a0591533b..dd0075c97c24 100644
--- a/drivers/iio/adc/ad7606_spi.c
+++ b/drivers/iio/adc/ad7606_spi.c
@@ -67,14 +67,14 @@ static const struct iio_chan_spec ad7616_sw_channels[] = {
 
 static const struct iio_chan_spec ad7606b_sw_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(8),
-	AD7616_CHANNEL(0),
-	AD7616_CHANNEL(1),
-	AD7616_CHANNEL(2),
-	AD7616_CHANNEL(3),
-	AD7616_CHANNEL(4),
-	AD7616_CHANNEL(5),
-	AD7616_CHANNEL(6),
-	AD7616_CHANNEL(7),
+	AD7606_SW_CHANNEL(0, 16),
+	AD7606_SW_CHANNEL(1, 16),
+	AD7606_SW_CHANNEL(2, 16),
+	AD7606_SW_CHANNEL(3, 16),
+	AD7606_SW_CHANNEL(4, 16),
+	AD7606_SW_CHANNEL(5, 16),
+	AD7606_SW_CHANNEL(6, 16),
+	AD7606_SW_CHANNEL(7, 16),
 };
 
 static const unsigned int ad7606B_oversampling_avail[9] = {
-- 
2.46.0