[PATCH v1 1/4] iio: adc: ad7949: define and use bitfield names

Liam Beguin
2021-07-08T23:56:43Z

From: Liam Beguin <lvb@xiphos.com>

Replace raw configuration register values by using FIELD_PREP and
defines to improve readability.

Signed-off-by: Liam Beguin <lvb@xiphos.com>
---
drivers/iio/adc/ad7949.c | 38 +++++++++++++++++++++++++++++++-------
1 file changed, 31 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/adc/ad7949.c b/drivers/iio/adc/ad7949.c
index 1b4b3203e428..93aacf4f680b 100644
--- a/drivers/iio/adc/ad7949.c
+++ b/drivers/iio/adc/ad7949.c
@@ -12,12 +12,27 @@
#include <linux/regulator/consumer.h>
#include <linux/spi/spi.h>

-#define AD7949_MASK_CHANNEL_SEL GENMASK(9, 7)
#define AD7949_MASK_TOTAL GENMASK(13, 0)
-#define AD7949_OFFSET_CHANNEL_SEL 7
-#define AD7949_CFG_READ_BACK 0x1
#define AD7949_CFG_REG_SIZE_BITS 14

+#define AD7949_CFG_BIT_CFG BIT(13)
+#define AD7949_CFG_VAL_CFG_OVERWRITE 1
+#define AD7949_CFG_VAL_CFG_KEEP 0
+#define AD7949_CFG_BIT_INCC GENMASK(12, 10)
+#define AD7949_CFG_VAL_INCC_UNIPOLAR_GND 7
+#define AD7949_CFG_VAL_INCC_UNIPOLAR_COMM 6
+#define AD7949_CFG_VAL_INCC_UNIPOLAR_DIFF 4
+#define AD7949_CFG_VAL_INCC_TEMP 3
+#define AD7949_CFG_VAL_INCC_BIPOLAR 2
+#define AD7949_CFG_VAL_INCC_BIPOLAR_DIFF 0
+#define AD7949_CFG_BIT_INX GENMASK(9, 7)
+#define AD7949_CFG_BIT_BW BIT(6)
+#define AD7949_CFG_VAL_BW_FULL 1
+#define AD7949_CFG_VAL_BW_QUARTER 0
+#define AD7949_CFG_BIT_REF GENMASK(5, 3)
+#define AD7949_CFG_BIT_SEQ GENMASK(2, 1)
+#define AD7949_CFG_BIT_RBN BIT(0)
+
enum {
ID_AD7949 = 0,
ID_AD7682,
@@ -109,8 +124,8 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val,
*/
for (i = 0; i < 2; i++) {
ret = ad7949_spi_write_cfg(ad7949_adc,
- channel << AD7949_OFFSET_CHANNEL_SEL,
- AD7949_MASK_CHANNEL_SEL);
+ FIELD_PREP(AD7949_CFG_BIT_INX, channel),
+ AD7949_CFG_BIT_INX);
if (ret)
return ret;
if (channel == ad7949_adc->current_channel)
@@ -214,10 +229,19 @@ static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc)
{
int ret;
int val;
+ u16 cfg;

- /* Sequencer disabled, CFG readback disabled, IN0 as default channel */
ad7949_adc->current_channel = 0;
- ret = ad7949_spi_write_cfg(ad7949_adc, 0x3C79, AD7949_MASK_TOTAL);
+
+ cfg = FIELD_PREP(AD7949_CFG_BIT_CFG, AD7949_CFG_VAL_CFG_OVERWRITE) |
+ FIELD_PREP(AD7949_CFG_BIT_INCC, AD7949_CFG_VAL_INCC_UNIPOLAR_GND) |
+ FIELD_PREP(AD7949_CFG_BIT_INX, ad7949_adc->current_channel) |
+ FIELD_PREP(AD7949_CFG_BIT_BW, AD7949_CFG_VAL_BW_FULL) |
+ FIELD_PREP(AD7949_CFG_BIT_REF, AD7949_REF_EXT_BUF) |
+ FIELD_PREP(AD7949_CFG_BIT_SEQ, 0x0) |
+ FIELD_PREP(AD7949_CFG_BIT_RBN, 1);
+
+ ret = ad7949_spi_write_cfg(ad7949_adc, cfg, AD7949_MASK_TOTAL);

/*
* Do two dummy conversions to apply the first configuration setting.
--
2.30.1.489.g328c10930387