iio: 104-quad-8: Provide defines for magic numbers

This patch adds several register and bit defines to help improve the
clarity of the code by cleaning up magic numbers throughout the driver.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/counter/104-quad-8.c b/drivers/iio/counter/104-quad-8.c
index 4be85ec54af4cc862df1d5f8ba2afce9beb6db71..92be8d0f7735fa0f7c3496b0550de4f9e721d791 100644 (file)
--- a/drivers/iio/counter/104-quad-8.c
+++ b/drivers/iio/counter/104-quad-8.c
@@ -59,6 +59,39 @@ struct quad8_iio {
        unsigned int base;
 };
 
+#define QUAD8_REG_CHAN_OP 0x11
+#define QUAD8_REG_INDEX_INPUT_LEVELS 0x16
+/* Borrow Toggle flip-flop */
+#define QUAD8_FLAG_BT BIT(0)
+/* Carry Toggle flip-flop */
+#define QUAD8_FLAG_CT BIT(1)
+/* Error flag */
+#define QUAD8_FLAG_E BIT(4)
+/* Up/Down flag */
+#define QUAD8_FLAG_UD BIT(5)
+/* Reset and Load Signal Decoders */
+#define QUAD8_CTR_RLD 0x00
+/* Counter Mode Register */
+#define QUAD8_CTR_CMR 0x20
+/* Input / Output Control Register */
+#define QUAD8_CTR_IOR 0x40
+/* Index Control Register */
+#define QUAD8_CTR_IDR 0x60
+/* Reset Byte Pointer (three byte data pointer) */
+#define QUAD8_RLD_RESET_BP 0x01
+/* Reset Counter */
+#define QUAD8_RLD_RESET_CNTR 0x02
+/* Reset Borrow Toggle, Carry Toggle, Compare Toggle, and Sign flags */
+#define QUAD8_RLD_RESET_FLAGS 0x04
+/* Reset Error flag */
+#define QUAD8_RLD_RESET_E 0x06
+/* Preset Register to Counter */
+#define QUAD8_RLD_PRESET_CNTR 0x08
+/* Transfer Counter to Output Latch */
+#define QUAD8_RLD_CNTR_OUT 0x10
+#define QUAD8_CHAN_OP_ENABLE_COUNTERS 0x00
+#define QUAD8_CHAN_OP_RESET_COUNTERS 0x01
+
 static int quad8_read_raw(struct iio_dev *indio_dev,
        struct iio_chan_spec const *chan, int *val, int *val2, long mask)
 {
@@ -72,19 +105,21 @@ static int quad8_read_raw(struct iio_dev *indio_dev,
        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                if (chan->type == IIO_INDEX) {
-                       *val = !!(inb(priv->base + 0x16) & BIT(chan->channel));
+                       *val = !!(inb(priv->base + QUAD8_REG_INDEX_INPUT_LEVELS)
+                               & BIT(chan->channel));
                        return IIO_VAL_INT;
                }
 
                flags = inb(base_offset + 1);
-               borrow = flags & BIT(0);
-               carry = !!(flags & BIT(1));
+               borrow = flags & QUAD8_FLAG_BT;
+               carry = !!(flags & QUAD8_FLAG_CT);
 
                /* Borrow XOR Carry effectively doubles count range */
                *val = (borrow ^ carry) << 24;
 
                /* Reset Byte Pointer; transfer Counter to Output Latch */
-               outb(0x11, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_CNTR_OUT,
+                    base_offset + 1);
 
                for (i = 0; i < 3; i++)
                        *val |= (unsigned int)inb(base_offset) << (8 * i);
@@ -120,17 +155,17 @@ static int quad8_write_raw(struct iio_dev *indio_dev,
                        return -EINVAL;
 
                /* Reset Byte Pointer */
-               outb(0x01, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
 
                /* Counter can only be set via Preset Register */
                for (i = 0; i < 3; i++)
                        outb(val >> (8 * i), base_offset);
 
                /* Transfer Preset Register to Counter */
-               outb(0x08, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_PRESET_CNTR, base_offset + 1);
 
                /* Reset Byte Pointer */
-               outb(0x01, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
 
                /* Set Preset Register back to original value */
                val = priv->preset[chan->channel];
@@ -138,9 +173,9 @@ static int quad8_write_raw(struct iio_dev *indio_dev,
                        outb(val >> (8 * i), base_offset);
 
                /* Reset Borrow, Carry, Compare, and Sign flags */
-               outb(0x04, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
                /* Reset Error flag */
-               outb(0x06, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
 
                return 0;
        case IIO_CHAN_INFO_ENABLE:
@@ -153,7 +188,7 @@ static int quad8_write_raw(struct iio_dev *indio_dev,
                ior_cfg = val | priv->preset_enable[chan->channel] << 1;
 
                /* Load I/O control configuration */
-               outb(0x40 | ior_cfg, base_offset + 1);
+               outb(QUAD8_CTR_IOR | ior_cfg, base_offset + 1);
 
                return 0;
        case IIO_CHAN_INFO_SCALE:
@@ -217,7 +252,7 @@ static ssize_t quad8_write_preset(struct iio_dev *indio_dev, uintptr_t private,
        priv->preset[chan->channel] = preset;
 
        /* Reset Byte Pointer */
-       outb(0x01, base_offset + 1);
+       outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
 
        /* Set Preset Register */
        for (i = 0; i < 3; i++)
@@ -258,7 +293,7 @@ static ssize_t quad8_write_set_to_preset_on_index(struct iio_dev *indio_dev,
                (unsigned int)preset_enable << 1;
 
        /* Load I/O control configuration to Input / Output Control Register */
-       outb(0x40 | ior_cfg, base_offset);
+       outb(QUAD8_CTR_IOR | ior_cfg, base_offset);
 
        return len;
 }
@@ -274,7 +309,7 @@ static int quad8_get_noise_error(struct iio_dev *indio_dev,
        struct quad8_iio *const priv = iio_priv(indio_dev);
        const int base_offset = priv->base + 2 * chan->channel + 1;
 
-       return !!(inb(base_offset) & BIT(4));
+       return !!(inb(base_offset) & QUAD8_FLAG_E);
 }
 
 static const struct iio_enum quad8_noise_error_enum = {
@@ -294,7 +329,7 @@ static int quad8_get_count_direction(struct iio_dev *indio_dev,
        struct quad8_iio *const priv = iio_priv(indio_dev);
        const int base_offset = priv->base + 2 * chan->channel + 1;
 
-       return !!(inb(base_offset) & BIT(5));
+       return !!(inb(base_offset) & QUAD8_FLAG_UD);
 }
 
 static const struct iio_enum quad8_count_direction_enum = {
@@ -324,7 +359,7 @@ static int quad8_set_count_mode(struct iio_dev *indio_dev,
                mode_cfg |= (priv->quadrature_scale[chan->channel] + 1) << 3;
 
        /* Load mode configuration to Counter Mode Register */
-       outb(0x20 | mode_cfg, base_offset);
+       outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
 
        return 0;
 }
@@ -364,7 +399,7 @@ static int quad8_set_synchronous_mode(struct iio_dev *indio_dev,
        priv->synchronous_mode[chan->channel] = synchronous_mode;
 
        /* Load Index Control configuration to Index Control Register */
-       outb(0x60 | idr_cfg, base_offset);
+       outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
 
        return 0;
 }
@@ -410,7 +445,7 @@ static int quad8_set_quadrature_mode(struct iio_dev *indio_dev,
        priv->quadrature_mode[chan->channel] = quadrature_mode;
 
        /* Load mode configuration to Counter Mode Register */
-       outb(0x20 | mode_cfg, base_offset);
+       outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
 
        return 0;
 }
@@ -446,7 +481,7 @@ static int quad8_set_index_polarity(struct iio_dev *indio_dev,
        priv->index_polarity[chan->channel] = index_polarity;
 
        /* Load Index Control configuration to Index Control Register */
-       outb(0x60 | idr_cfg, base_offset);
+       outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
 
        return 0;
 }
@@ -556,28 +591,28 @@ static int quad8_probe(struct device *dev, unsigned int id)
        priv->base = base[id];
 
        /* Reset all counters and disable interrupt function */
-       outb(0x01, base[id] + 0x11);
+       outb(QUAD8_CHAN_OP_RESET_COUNTERS, base[id] + QUAD8_REG_CHAN_OP);
        /* Set initial configuration for all counters */
        for (i = 0; i < QUAD8_NUM_COUNTERS; i++) {
                base_offset = base[id] + 2 * i;
                /* Reset Byte Pointer */
-               outb(0x01, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
                /* Reset Preset Register */
                for (j = 0; j < 3; j++)
                        outb(0x00, base_offset);
                /* Reset Borrow, Carry, Compare, and Sign flags */
-               outb(0x04, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
                /* Reset Error flag */
-               outb(0x06, base_offset + 1);
+               outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
                /* Binary encoding; Normal count; non-quadrature mode */
-               outb(0x20, base_offset + 1);
+               outb(QUAD8_CTR_CMR, base_offset + 1);
                /* Disable A and B inputs; preset on index; FLG1 as Carry */
-               outb(0x40, base_offset + 1);
+               outb(QUAD8_CTR_IOR, base_offset + 1);
                /* Disable index function; negative index polarity */
-               outb(0x60, base_offset + 1);
+               outb(QUAD8_CTR_IDR, base_offset + 1);
        }
        /* Enable all counters */
-       outb(0x00, base[id] + 0x11);
+       outb(QUAD8_CHAN_OP_ENABLE_COUNTERS, base[id] + QUAD8_REG_CHAN_OP);
 
        return devm_iio_device_register(dev, indio_dev);
 }