staging:iio:ad799x: Simplify threshold register look-up

Given a channel number the corresponding threshold and hysteresis registers can
easily be calculated. No need to use a look-up table.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/ad799x.h b/drivers/staging/iio/adc/ad799x.h
index b51680c1c331a65593a531a93ec6f1bd6f1b191c..a591aa6feae142dc0eaa3507e8f5ad0279396ab7 100644 (file)
--- a/drivers/staging/iio/adc/ad799x.h
+++ b/drivers/staging/iio/adc/ad799x.h
@@ -36,18 +36,10 @@
 #define AD7998_ALERT_STAT_REG                  0x1
 #define AD7998_CONF_REG                                0x2
 #define AD7998_CYCLE_TMR_REG                   0x3
-#define AD7998_DATALOW_CH1_REG                 0x4
-#define AD7998_DATAHIGH_CH1_REG                        0x5
-#define AD7998_HYST_CH1_REG                    0x6
-#define AD7998_DATALOW_CH2_REG                 0x7
-#define AD7998_DATAHIGH_CH2_REG                        0x8
-#define AD7998_HYST_CH2_REG                    0x9
-#define AD7998_DATALOW_CH3_REG                 0xA
-#define AD7998_DATAHIGH_CH3_REG                        0xB
-#define AD7998_HYST_CH3_REG                    0xC
-#define AD7998_DATALOW_CH4_REG                 0xD
-#define AD7998_DATAHIGH_CH4_REG                        0xE
-#define AD7998_HYST_CH4_REG                    0xF
+
+#define AD7998_DATALOW_REG(x)                  ((x) * 3 + 0x4)
+#define AD7998_DATAHIGH_REG(x)                 ((x) * 3 + 0x5)
+#define AD7998_HYST_REG(x)                     ((x) * 3 + 0x6)
 
 #define AD7998_CYC_MASK                                0x7
 #define AD7998_CYC_DIS                         0x0

diff --git a/drivers/staging/iio/adc/ad799x_core.c b/drivers/staging/iio/adc/ad799x_core.c
index 57bc540b14ae3001ad9c8a4105b699a5965aab31..fa0ada1b1c5263f5ca90f4a8eaf4720a68b4482d 100644 (file)
--- a/drivers/staging/iio/adc/ad799x_core.c
+++ b/drivers/staging/iio/adc/ad799x_core.c
@@ -259,12 +259,14 @@ static int ad799x_read_event_config(struct iio_dev *indio_dev,
        return 1;
 }
 
-static const u8 ad799x_threshold_addresses[][2] = {
-       { AD7998_DATALOW_CH1_REG, AD7998_DATAHIGH_CH1_REG },
-       { AD7998_DATALOW_CH2_REG, AD7998_DATAHIGH_CH2_REG },
-       { AD7998_DATALOW_CH3_REG, AD7998_DATAHIGH_CH3_REG },
-       { AD7998_DATALOW_CH4_REG, AD7998_DATAHIGH_CH4_REG },
-};
+static int ad799x_threshold_reg(const struct iio_chan_spec *chan,
+                                       enum iio_event_direction dir)
+{
+       if (dir == IIO_EV_DIR_FALLING)
+               return AD7998_DATALOW_REG(chan->channel);
+       else
+               return AD7998_DATAHIGH_REG(chan->channel);
+}
 
 static int ad799x_write_event_value(struct iio_dev *indio_dev,
                                    const struct iio_chan_spec *chan,
@@ -275,13 +277,9 @@ static int ad799x_write_event_value(struct iio_dev *indio_dev,
 {
        int ret;
        struct ad799x_state *st = iio_priv(indio_dev);
-       int direction = dir == IIO_EV_DIR_FALLING;
-       int number = chan->channel;
 
        mutex_lock(&indio_dev->mlock);
-       ret = ad799x_i2c_write16(st,
-                                ad799x_threshold_addresses[number][direction],
-                                val);
+       ret = ad799x_i2c_write16(st, ad799x_threshold_reg(chan, dir), val);
        mutex_unlock(&indio_dev->mlock);
 
        return ret;
@@ -296,14 +294,10 @@ static int ad799x_read_event_value(struct iio_dev *indio_dev,
 {
        int ret;
        struct ad799x_state *st = iio_priv(indio_dev);
-       int direction = dir == IIO_EV_DIR_FALLING;
-       int number = chan->channel;
        u16 valin;
 
        mutex_lock(&indio_dev->mlock);
-       ret = ad799x_i2c_read16(st,
-                               ad799x_threshold_addresses[number][direction],
-                               &valin);
+       ret = ad799x_i2c_read16(st, ad799x_threshold_reg(chan, dir), &valin);
        mutex_unlock(&indio_dev->mlock);
        if (ret < 0)
                return ret;
@@ -391,25 +385,25 @@ static IIO_DEVICE_ATTR(in_voltage0_thresh_both_hyst_raw,
                       S_IRUGO | S_IWUSR,
                       ad799x_read_channel_config,
                       ad799x_write_channel_config,
-                      AD7998_HYST_CH1_REG);
+                      AD7998_HYST_REG(0));
 
 static IIO_DEVICE_ATTR(in_voltage1_thresh_both_hyst_raw,
                       S_IRUGO | S_IWUSR,
                       ad799x_read_channel_config,
                       ad799x_write_channel_config,
-                      AD7998_HYST_CH2_REG);
+                      AD7998_HYST_REG(1));
 
 static IIO_DEVICE_ATTR(in_voltage2_thresh_both_hyst_raw,
                       S_IRUGO | S_IWUSR,
                       ad799x_read_channel_config,
                       ad799x_write_channel_config,
-                      AD7998_HYST_CH3_REG);
+                      AD7998_HYST_REG(2));
 
 static IIO_DEVICE_ATTR(in_voltage3_thresh_both_hyst_raw,
                       S_IRUGO | S_IWUSR,
                       ad799x_read_channel_config,
                       ad799x_write_channel_config,
-                      AD7998_HYST_CH4_REG);
+                      AD7998_HYST_REG(3));
 
 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
                              ad799x_read_frequency,