staging: iio: cdc: ad7746: Break up use of chan->address and use FIELD_PREP etc

Instead of encoding several different fields into chan->address use
an indirection to a separate per channel structure where the various
fields can be expressed in a more readable form.  This also allows
the register values to be constructed at runtime using FIELD_PREP().

Drop the now redundant _SHIFT macros.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220626122938.582107-9-jic23@kernel.org

diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
index bc03760e44e07697f618c52aac2994cefec19c8b..3e4448f3f3dd11dba9ad0fc3f7eb3f06ac99668c 100644 (file)
--- a/drivers/staging/iio/cdc/ad7746.c
+++ b/drivers/staging/iio/cdc/ad7746.c
@@ -5,6 +5,7 @@
  * Copyright 2011 Analog Devices Inc.
  */
 
+#include <linux/bitfield.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/i2c.h>
@@ -50,11 +51,12 @@
 #define AD7746_CAPSETUP_CACHOP         BIT(0)
 
 /* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */
-#define AD7746_VTSETUP_VTEN            (1 << 7)
-#define AD7746_VTSETUP_VTMD_INT_TEMP   (0 << 5)
-#define AD7746_VTSETUP_VTMD_EXT_TEMP   (1 << 5)
-#define AD7746_VTSETUP_VTMD_VDD_MON    (2 << 5)
-#define AD7746_VTSETUP_VTMD_EXT_VIN    (3 << 5)
+#define AD7746_VTSETUP_VTEN            BIT(7)
+#define AD7746_VTSETUP_VTMD_MASK       GENMASK(6, 5)
+#define AD7746_VTSETUP_VTMD_INT_TEMP   0
+#define AD7746_VTSETUP_VTMD_EXT_TEMP   1
+#define AD7746_VTSETUP_VTMD_VDD_MON    2
+#define AD7746_VTSETUP_VTMD_EXT_VIN    3
 #define AD7746_VTSETUP_EXTREF          BIT(4)
 #define AD7746_VTSETUP_VTSHORT         BIT(1)
 #define AD7746_VTSETUP_VTCHOP          BIT(0)
@@ -66,23 +68,22 @@
 #define AD7746_EXCSETUP_NEXCB          BIT(4)
 #define AD7746_EXCSETUP_EXCA           BIT(3)
 #define AD7746_EXCSETUP_NEXCA          BIT(2)
-#define AD7746_EXCSETUP_EXCLVL(x)      (((x) & 0x3) << 0)
+#define AD7746_EXCSETUP_EXCLVL_MASK    GENMASK(1, 0)
 
 /* Config Register Bit Designations (AD7746_REG_CFG) */
-#define AD7746_CONF_VTFS_SHIFT         6
-#define AD7746_CONF_CAPFS_SHIFT                3
 #define AD7746_CONF_VTFS_MASK          GENMASK(7, 6)
 #define AD7746_CONF_CAPFS_MASK         GENMASK(5, 3)
-#define AD7746_CONF_MODE_IDLE          (0 << 0)
-#define AD7746_CONF_MODE_CONT_CONV     (1 << 0)
-#define AD7746_CONF_MODE_SINGLE_CONV   (2 << 0)
-#define AD7746_CONF_MODE_PWRDN         (3 << 0)
-#define AD7746_CONF_MODE_OFFS_CAL      (5 << 0)
-#define AD7746_CONF_MODE_GAIN_CAL      (6 << 0)
+#define AD7746_CONF_MODE_MASK          GENMASK(2, 0)
+#define AD7746_CONF_MODE_IDLE          0
+#define AD7746_CONF_MODE_CONT_CONV     1
+#define AD7746_CONF_MODE_SINGLE_CONV   2
+#define AD7746_CONF_MODE_PWRDN         3
+#define AD7746_CONF_MODE_OFFS_CAL      5
+#define AD7746_CONF_MODE_GAIN_CAL      6
 
 /* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */
 #define AD7746_CAPDAC_DACEN            BIT(7)
-#define AD7746_CAPDAC_DACP(x)          ((x) & 0x7F)
+#define AD7746_CAPDAC_DACP_MASK                GENMASK(6, 0)
 
 struct ad7746_chip_info {
        struct i2c_client *client;
@@ -109,6 +110,52 @@ enum ad7746_chan {
        CIN2_DIFF,
 };
 
+struct ad7746_chan_info {
+       u8 addr;
+       union {
+               u8 vtmd;
+               struct { /* CAP SETUP fields */
+                       unsigned int cin2 : 1;
+                       unsigned int capdiff : 1;
+               };
+       };
+};
+
+static const struct ad7746_chan_info ad7746_chan_info[] = {
+       [VIN] = {
+               .addr = AD7746_REG_VT_DATA_HIGH,
+               .vtmd = AD7746_VTSETUP_VTMD_EXT_VIN,
+       },
+       [VIN_VDD] = {
+               .addr = AD7746_REG_VT_DATA_HIGH,
+               .vtmd = AD7746_VTSETUP_VTMD_VDD_MON,
+       },
+       [TEMP_INT] = {
+               .addr = AD7746_REG_VT_DATA_HIGH,
+               .vtmd = AD7746_VTSETUP_VTMD_INT_TEMP,
+       },
+       [TEMP_EXT] = {
+               .addr = AD7746_REG_VT_DATA_HIGH,
+               .vtmd = AD7746_VTSETUP_VTMD_EXT_TEMP,
+       },
+       [CIN1] = {
+               .addr = AD7746_REG_CAP_DATA_HIGH,
+       },
+       [CIN1_DIFF] = {
+               .addr =  AD7746_REG_CAP_DATA_HIGH,
+               .capdiff = 1,
+       },
+       [CIN2] = {
+               .addr = AD7746_REG_CAP_DATA_HIGH,
+               .cin2 = 1,
+       },
+       [CIN2_DIFF] = {
+               .addr = AD7746_REG_CAP_DATA_HIGH,
+               .cin2 = 1,
+               .capdiff = 1,
+       },
+};
+
 static const struct iio_chan_spec ad7746_channels[] = {
        [VIN] = {
                .type = IIO_VOLTAGE,
@@ -116,8 +163,7 @@ static const struct iio_chan_spec ad7746_channels[] = {
                .channel = 0,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
-               .address = AD7746_REG_VT_DATA_HIGH << 8 |
-                       AD7746_VTSETUP_VTMD_EXT_VIN,
+               .address = VIN,
        },
        [VIN_VDD] = {
                .type = IIO_VOLTAGE,
@@ -126,24 +172,21 @@ static const struct iio_chan_spec ad7746_channels[] = {
                .extend_name = "supply",
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
-               .address = AD7746_REG_VT_DATA_HIGH << 8 |
-                       AD7746_VTSETUP_VTMD_VDD_MON,
+               .address = VIN_VDD,
        },
        [TEMP_INT] = {
                .type = IIO_TEMP,
                .indexed = 1,
                .channel = 0,
                .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
-               .address = AD7746_REG_VT_DATA_HIGH << 8 |
-                       AD7746_VTSETUP_VTMD_INT_TEMP,
+               .address = TEMP_INT,
        },
        [TEMP_EXT] = {
                .type = IIO_TEMP,
                .indexed = 1,
                .channel = 1,
                .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
-               .address = AD7746_REG_VT_DATA_HIGH << 8 |
-                       AD7746_VTSETUP_VTMD_EXT_TEMP,
+               .address = TEMP_EXT,
        },
        [CIN1] = {
                .type = IIO_CAPACITANCE,
@@ -153,7 +196,7 @@ static const struct iio_chan_spec ad7746_channels[] = {
                BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
                BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
-               .address = AD7746_REG_CAP_DATA_HIGH << 8,
+               .address = CIN1,
        },
        [CIN1_DIFF] = {
                .type = IIO_CAPACITANCE,
@@ -165,8 +208,7 @@ static const struct iio_chan_spec ad7746_channels[] = {
                BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
                BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
-               .address = AD7746_REG_CAP_DATA_HIGH << 8 |
-                       AD7746_CAPSETUP_CAPDIFF
+               .address = CIN1_DIFF,
        },
        [CIN2] = {
                .type = IIO_CAPACITANCE,
@@ -176,8 +218,7 @@ static const struct iio_chan_spec ad7746_channels[] = {
                BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
                BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
-               .address = AD7746_REG_CAP_DATA_HIGH << 8 |
-                       AD7746_CAPSETUP_CIN2,
+               .address = CIN2,
        },
        [CIN2_DIFF] = {
                .type = IIO_CAPACITANCE,
@@ -189,8 +230,7 @@ static const struct iio_chan_spec ad7746_channels[] = {
                BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
                BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
-               .address = AD7746_REG_CAP_DATA_HIGH << 8 |
-                       AD7746_CAPSETUP_CAPDIFF | AD7746_CAPSETUP_CIN2,
+               .address = CIN2_DIFF,
        }
 };
 
@@ -226,10 +266,13 @@ static int ad7746_select_channel(struct iio_dev *indio_dev,
 
        switch (chan->type) {
        case IIO_CAPACITANCE:
-               cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
+               cap_setup = FIELD_PREP(AD7746_CAPSETUP_CIN2,
+                                      ad7746_chan_info[chan->address].cin2) |
+                       FIELD_PREP(AD7746_CAPSETUP_CAPDIFF,
+                                  ad7746_chan_info[chan->address].capdiff) |
+                       FIELD_PREP(AD7746_CAPSETUP_CAPEN, 1);
                vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
-               idx = (chip->config & AD7746_CONF_CAPFS_MASK) >>
-                       AD7746_CONF_CAPFS_SHIFT;
+               idx = FIELD_GET(AD7746_CONF_CAPFS_MASK, chip->config);
                delay = ad7746_cap_filter_rate_table[idx][1];
 
                ret = ad7746_set_capdac(chip, chan->channel);
@@ -241,10 +284,11 @@ static int ad7746_select_channel(struct iio_dev *indio_dev,
                break;
        case IIO_VOLTAGE:
        case IIO_TEMP:
-               vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
+               vt_setup = FIELD_PREP(AD7746_VTSETUP_VTMD_MASK,
+                                     ad7746_chan_info[chan->address].vtmd) |
+                       FIELD_PREP(AD7746_VTSETUP_VTEN, 1);
                cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
-               idx = (chip->config & AD7746_CONF_VTFS_MASK) >>
-                       AD7746_CONF_VTFS_SHIFT;
+               idx = FIELD_GET(AD7746_CONF_VTFS_MASK, chip->config);
                delay = ad7746_cap_filter_rate_table[idx][1];
                break;
        default:
@@ -327,7 +371,8 @@ static ssize_t ad7746_start_offset_calib(struct device *dev,
                return ret;
 
        return ad7746_start_calib(dev, attr, buf, len,
-                                 AD7746_CONF_MODE_OFFS_CAL);
+                                 FIELD_PREP(AD7746_CONF_MODE_MASK,
+                                            AD7746_CONF_MODE_OFFS_CAL));
 }
 
 static ssize_t ad7746_start_gain_calib(struct device *dev,
@@ -342,7 +387,8 @@ static ssize_t ad7746_start_gain_calib(struct device *dev,
                return ret;
 
        return ad7746_start_calib(dev, attr, buf, len,
-                                 AD7746_CONF_MODE_GAIN_CAL);
+                                 FIELD_PREP(AD7746_CONF_MODE_MASK,
+                                            AD7746_CONF_MODE_GAIN_CAL));
 }
 
 static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
@@ -369,7 +415,7 @@ static int ad7746_store_cap_filter_rate_setup(struct ad7746_chip_info *chip,
                i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
 
        chip->config &= ~AD7746_CONF_CAPFS_MASK;
-       chip->config |= i << AD7746_CONF_CAPFS_SHIFT;
+       chip->config |= FIELD_PREP(AD7746_CONF_CAPFS_MASK, i);
 
        return 0;
 }
@@ -387,7 +433,7 @@ static int ad7746_store_vt_filter_rate_setup(struct ad7746_chip_info *chip,
                i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
 
        chip->config &= ~AD7746_CONF_VTFS_MASK;
-       chip->config |= i << AD7746_CONF_VTFS_SHIFT;
+       chip->config |= FIELD_PREP(AD7746_CONF_VTFS_MASK, i);
 
        return 0;
 }
@@ -470,7 +516,7 @@ static int ad7746_write_raw(struct iio_dev *indio_dev,
                val /= 338646;
                mutex_lock(&chip->lock);
                chip->capdac[chan->channel][chan->differential] = val > 0 ?
-                       AD7746_CAPDAC_DACP(val) | AD7746_CAPDAC_DACEN : 0;
+                       FIELD_PREP(AD7746_CAPDAC_DACP_MASK, val) | AD7746_CAPDAC_DACEN : 0;
 
                ret = ad7746_set_capdac(chip, chan->channel);
                if (ret < 0) {
@@ -519,14 +565,16 @@ static int ad7746_read_channel(struct iio_dev *indio_dev,
                return ret;
        delay = ret;
 
-       regval = chip->config | AD7746_CONF_MODE_SINGLE_CONV;
+       regval = chip->config | FIELD_PREP(AD7746_CONF_MODE_MASK,
+                                          AD7746_CONF_MODE_SINGLE_CONV);
        ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
        if (ret < 0)
                return ret;
 
        msleep(delay);
        /* Now read the actual register */
-       ret = i2c_smbus_read_i2c_block_data(chip->client,  chan->address >> 8,
+       ret = i2c_smbus_read_i2c_block_data(chip->client,
+                                           ad7746_chan_info[chan->address].addr,
                                            sizeof(data), data);
        if (ret < 0)
                return ret;
@@ -600,8 +648,8 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
 
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_OFFSET:
-               *val = AD7746_CAPDAC_DACP(chip->capdac[chan->channel]
-                                         [chan->differential]) * 338646;
+               *val = FIELD_GET(AD7746_CAPDAC_DACP_MASK,
+                                chip->capdac[chan->channel][chan->differential]) * 338646;
 
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
@@ -624,13 +672,11 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
        case IIO_CHAN_INFO_SAMP_FREQ:
                switch (chan->type) {
                case IIO_CAPACITANCE:
-                       idx = (chip->config & AD7746_CONF_CAPFS_MASK) >>
-                               AD7746_CONF_CAPFS_SHIFT;
+                       idx = FIELD_GET(AD7746_CONF_CAPFS_MASK, chip->config);
                        *val = ad7746_cap_filter_rate_table[idx][0];
                        return IIO_VAL_INT;
                case IIO_VOLTAGE:
-                       idx = (chip->config & AD7746_CONF_VTFS_MASK) >>
-                               AD7746_CONF_VTFS_SHIFT;
+                       idx = FIELD_GET(AD7746_CONF_VTFS_MASK, chip->config);
                        *val = ad7746_vt_filter_rate_table[idx][0];
                        return IIO_VAL_INT;
                default:
@@ -696,16 +742,16 @@ static int ad7746_probe(struct i2c_client *client,
        if (!ret) {
                switch (vdd_permille) {
                case 125:
-                       regval |= AD7746_EXCSETUP_EXCLVL(0);
+                       regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 0);
                        break;
                case 250:
-                       regval |= AD7746_EXCSETUP_EXCLVL(1);
+                       regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 1);
                        break;
                case 375:
-                       regval |= AD7746_EXCSETUP_EXCLVL(2);
+                       regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 2);
                        break;
                case 500:
-                       regval |= AD7746_EXCSETUP_EXCLVL(3);
+                       regval |= FIELD_PREP(AD7746_EXCSETUP_EXCLVL_MASK, 3);
                        break;
                default:
                        break;