staging: iio: cdc: ad7746: add additional config defines

Introduce defines for shifting and mask under the config register for
better readability. Also, introduce helper variables for index
calculation.

Signed-off-by: Eva Rachel Retuya <eraretuya@gmail.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
index a5828f9..81f8b9e 100644 (file)
--- a/drivers/staging/iio/cdc/ad7746.c
+++ b/drivers/staging/iio/cdc/ad7746.c
@@ -70,8 +70,10 @@
 #define AD7746_EXCSETUP_EXCLVL(x)      (((x) & 0x3) << 0)
 
 /* Config Register Bit Designations (AD7746_REG_CFG) */
-#define AD7746_CONF_VTFS(x)            ((x) << 6)
-#define AD7746_CONF_CAPFS(x)           ((x) << 3)
+#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)
@@ -217,15 +219,16 @@ static int ad7746_select_channel(struct iio_dev *indio_dev,
                            struct iio_chan_spec const *chan)
 {
        struct ad7746_chip_info *chip = iio_priv(indio_dev);
-       int ret, delay;
+       int ret, delay, idx;
        u8 vt_setup, cap_setup;
 
        switch (chan->type) {
        case IIO_CAPACITANCE:
                cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
                vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
-               delay = ad7746_cap_filter_rate_table[(chip->config >> 3) &
-                       0x7][1];
+               idx = (chip->config & AD7746_CONF_CAPFS_MASK) >>
+                       AD7746_CONF_CAPFS_SHIFT;
+               delay = ad7746_cap_filter_rate_table[idx][1];
 
                if (chip->capdac_set != chan->channel) {
                        ret = i2c_smbus_write_byte_data(chip->client,
@@ -246,8 +249,9 @@ static int ad7746_select_channel(struct iio_dev *indio_dev,
        case IIO_TEMP:
                vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
                cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
-               delay = ad7746_cap_filter_rate_table[(chip->config >> 6) &
-                       0x3][1];
+               idx = (chip->config & AD7746_CONF_VTFS_MASK) >>
+                       AD7746_CONF_VTFS_SHIFT;
+               delay = ad7746_cap_filter_rate_table[idx][1];
                break;
        default:
                return -EINVAL;
@@ -369,8 +373,8 @@ static int ad7746_store_cap_filter_rate_setup(struct ad7746_chip_info *chip,
        if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table))
                i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
 
-       chip->config &= ~AD7746_CONF_CAPFS(0x7);
-       chip->config |= AD7746_CONF_CAPFS(i);
+       chip->config &= ~AD7746_CONF_CAPFS_MASK;
+       chip->config |= i << AD7746_CONF_CAPFS_SHIFT;
 
        return 0;
 }
@@ -387,8 +391,8 @@ static int ad7746_store_vt_filter_rate_setup(struct ad7746_chip_info *chip,
        if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table))
                i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
 
-       chip->config &= ~AD7746_CONF_VTFS(0x3);
-       chip->config |= AD7746_CONF_VTFS(i);
+       chip->config &= ~AD7746_CONF_VTFS_MASK;
+       chip->config |= i << AD7746_CONF_VTFS_SHIFT;
 
        return 0;
 }
@@ -527,7 +531,7 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
                           long mask)
 {
        struct ad7746_chip_info *chip = iio_priv(indio_dev);
-       int ret, delay;
+       int ret, delay, idx;
        u8 regval, reg;
 
        mutex_lock(&indio_dev->mlock);
@@ -635,13 +639,15 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
        case IIO_CHAN_INFO_SAMP_FREQ:
                switch (chan->type) {
                case IIO_CAPACITANCE:
-                       *val = ad7746_cap_filter_rate_table[
-                                       (chip->config >> 3) & 0x7][0];
+                       idx = (chip->config & AD7746_CONF_CAPFS_MASK) >>
+                               AD7746_CONF_CAPFS_SHIFT;
+                       *val = ad7746_cap_filter_rate_table[idx][0];
                        ret = IIO_VAL_INT;
                        break;
                case IIO_VOLTAGE:
-                       *val = ad7746_vt_filter_rate_table[
-                                       (chip->config >> 6) & 0x3][0];
+                       idx = (chip->config & AD7746_CONF_VTFS_MASK) >>
+                               AD7746_CONF_VTFS_SHIFT;
+                       *val = ad7746_vt_filter_rate_table[idx][0];
                        ret = IIO_VAL_INT;
                        break;
                default: