staging:iio:adc:ad7152 bring more into line with abi.
authorJonathan Cameron <jic23@cam.ac.uk>
Fri, 2 Sep 2011 16:25:25 +0000 (17:25 +0100)
committerGreg Kroah-Hartman <gregkh@suse.de>
Tue, 6 Sep 2011 23:03:28 +0000 (16:03 -0700)
Get rid of explicit writes to registers and conversion mode
control.

Couple of bits I'm unsure about.
* Do calibration modes self reset when done?  How do you tell they are
done?

* Should we poll the status register just to be sure we have a new conversion?

All done sans hardware.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Michael Hennerich <Michael.Hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/staging/iio/adc/ad7152.c

index 1ec012d..4ac5d7f 100644 (file)
@@ -13,6 +13,7 @@
 #include <linux/sysfs.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
+#include <linux/delay.h>
 
 #include "../iio.h"
 #include "../sysfs.h"
 
 struct ad7152_chip_info {
        struct i2c_client *client;
-       u8  ch1_setup;
-       u8  ch2_setup;
        /*
         * Capacitive channel digital filter setup;
         * conversion time/update rate setup per channel
         */
        u8  filter_rate_setup;
-       char *conversion_mode;
 };
 
-struct ad7152_conversion_mode {
-       char *name;
-       u8 reg_cfg;
-};
-
-static struct ad7152_conversion_mode
-ad7152_conv_mode_table[AD7152_MAX_CONV_MODE] = {
-       { "idle", 0 },
-       { "continuous-conversion", 1 },
-       { "single-conversion", 2 },
-       { "power-down", 3 },
-       { "offset-calibration", 5 },
-       { "gain-calibration", 6 },
-};
-
-/*
- * sysfs nodes
- */
-
-#define IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(_show)                     \
-       IIO_DEVICE_ATTR(available_conversion_modes, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_CONVERSION_MODE(_mode, _show, _store)              \
-       IIO_DEVICE_ATTR(conversion_mode, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CH1_SETUP(_mode, _show, _store)           \
-       IIO_DEVICE_ATTR(ch1_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CH2_SETUP(_mode, _show, _store)              \
-       IIO_DEVICE_ATTR(ch2_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_FILTER_RATE_SETUP(_mode, _show, _store)              \
-       IIO_DEVICE_ATTR(filter_rate_setup, _mode, _show, _store, 0)
-
-static ssize_t ad7152_show_conversion_modes(struct device *dev,
-               struct device_attribute *attr,
-               char *buf)
-{
-       int i;
-       int len = 0;
-
-       for (i = 0; i < AD7152_MAX_CONV_MODE; i++)
-               len += sprintf(buf + len, "%s ",
-                              ad7152_conv_mode_table[i].name);
-
-       len += sprintf(buf + len, "\n");
-
-       return len;
-}
-
-static IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(ad7152_show_conversion_modes);
-
-static ssize_t ad7152_show_conversion_mode(struct device *dev,
-               struct device_attribute *attr,
-               char *buf)
+static inline ssize_t ad7152_start_calib(struct device *dev,
+                                        struct device_attribute *attr,
+                                        const char *buf,
+                                        size_t len,
+                                        u8 regval)
 {
        struct iio_dev *dev_info = dev_get_drvdata(dev);
        struct ad7152_chip_info *chip = iio_priv(dev_info);
+       struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+       bool doit;
+       int ret;
 
-       return sprintf(buf, "%s\n", chip->conversion_mode);
-}
-
-static ssize_t ad7152_store_conversion_mode(struct device *dev,
-               struct device_attribute *attr,
-               const char *buf,
-               size_t len)
-{
-       struct iio_dev *dev_info = dev_get_drvdata(dev);
-       struct ad7152_chip_info *chip = iio_priv(dev_info);
-       u8 cfg;
-       int i, ret;
-
-       ret = i2c_smbus_read_byte_data(chip->client, AD7152_CFG);
+       ret = strtobool(buf, &doit);
        if (ret < 0)
                return ret;
-       cfg = ret;
-
-       for (i = 0; i < AD7152_MAX_CONV_MODE; i++)
-               if (strncmp(buf, ad7152_conv_mode_table[i].name,
-                               strlen(ad7152_conv_mode_table[i].name) - 1) ==
-                   0) {
-                       chip->conversion_mode = ad7152_conv_mode_table[i].name;
-                       cfg |= 0x18 | ad7152_conv_mode_table[i].reg_cfg;
-                       ret = i2c_smbus_write_byte_data(chip->client,
-                                                       AD7152_CFG, cfg);
-                       if (ret < 0)
-                               return ret;
-                       return len;
-               }
-
-       dev_err(dev, "not supported conversion mode\n");
-
-       return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CONVERSION_MODE(S_IRUGO | S_IWUSR,
-               ad7152_show_conversion_mode,
-               ad7152_store_conversion_mode);
-
-static ssize_t ad7152_show_ch1_setup(struct device *dev,
-               struct device_attribute *attr,
-               char *buf)
-{
-       struct iio_dev *dev_info = dev_get_drvdata(dev);
-       struct ad7152_chip_info *chip = iio_priv(dev_info);
-
-       return sprintf(buf, "0x%02x\n", chip->ch1_setup);
-}
 
-static ssize_t ad7152_store_ch1_setup(struct device *dev,
-               struct device_attribute *attr,
-               const char *buf,
-               size_t len)
-{
-       struct iio_dev *dev_info = dev_get_drvdata(dev);
-       struct ad7152_chip_info *chip = iio_priv(dev_info);
-       u8 data;
-       int ret;
+       if (!doit)
+               return 0;
 
-       ret = kstrtou8(buf, 10, &data);
-       if (ret < 0)
-               return ret;
+       if (this_attr->address == 0)
+               regval |= (1 << 4);
+       else
+               regval |= (1 << 3);
 
-       ret = i2c_smbus_write_byte_data(chip->client, AD7152_CH1_SETUP, data);
+       ret = i2c_smbus_write_byte_data(chip->client, AD7152_CFG, regval);
        if (ret < 0)
                return ret;
-
-       chip->ch1_setup = data;
-
+       /* Unclear on period this should be set for or whether it flips back
+        * to idle automatically */
        return len;
 }
-
-static IIO_DEV_ATTR_CH1_SETUP(S_IRUGO | S_IWUSR,
-               ad7152_show_ch1_setup,
-               ad7152_store_ch1_setup);
-
-static ssize_t ad7152_show_ch2_setup(struct device *dev,
-               struct device_attribute *attr,
-               char *buf)
+static ssize_t ad7152_start_offset_calib(struct device *dev,
+                                        struct device_attribute *attr,
+                                        const char *buf,
+                                        size_t len)
 {
-       struct iio_dev *dev_info = dev_get_drvdata(dev);
-       struct ad7152_chip_info *chip = iio_priv(dev_info);
 
-       return sprintf(buf, "0x%02x\n", chip->ch2_setup);
+       return ad7152_start_calib(dev, attr, buf, len, 5);
 }
-
-static ssize_t ad7152_store_ch2_setup(struct device *dev,
-               struct device_attribute *attr,
-               const char *buf,
-               size_t len)
+static ssize_t ad7152_start_gain_calib(struct device *dev,
+                                      struct device_attribute *attr,
+                                      const char *buf,
+                                      size_t len)
 {
-       struct iio_dev *dev_info = dev_get_drvdata(dev);
-       struct ad7152_chip_info *chip = iio_priv(dev_info);
-       u8 data;
-       int ret;
-
-       ret = kstrtou8(buf, 10, &data);
-       if (ret < 0)
-               return ret;
-
-       ret = i2c_smbus_write_byte_data(chip->client, AD7152_CH2_SETUP, data);
-       if (ret < 0)
-               return ret;
-
-       chip->ch2_setup = data;
-
-       return len;
+       return ad7152_start_calib(dev, attr, buf, len, 6);
 }
 
-static IIO_DEV_ATTR_CH2_SETUP(S_IRUGO | S_IWUSR,
-               ad7152_show_ch2_setup,
-               ad7152_store_ch2_setup);
+static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
+                      S_IWUSR, NULL, ad7152_start_offset_calib, 0);
+static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration,
+                      S_IWUSR, NULL, ad7152_start_offset_calib, 1);
+static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration,
+                      S_IWUSR, NULL, ad7152_start_gain_calib, 0);
+static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration,
+                      S_IWUSR, NULL, ad7152_start_gain_calib, 1);
+
+#define IIO_DEV_ATTR_FILTER_RATE_SETUP(_mode, _show, _store)              \
+       IIO_DEVICE_ATTR(filter_rate_setup, _mode, _show, _store, 0)
 
 static ssize_t ad7152_show_filter_rate_setup(struct device *dev,
                struct device_attribute *attr,
@@ -266,11 +154,11 @@ static IIO_DEV_ATTR_FILTER_RATE_SETUP(S_IRUGO | S_IWUSR,
                ad7152_store_filter_rate_setup);
 
 static struct attribute *ad7152_attributes[] = {
-       &iio_dev_attr_available_conversion_modes.dev_attr.attr,
-       &iio_dev_attr_conversion_mode.dev_attr.attr,
-       &iio_dev_attr_ch1_setup.dev_attr.attr,
-       &iio_dev_attr_ch2_setup.dev_attr.attr,
        &iio_dev_attr_filter_rate_setup.dev_attr.attr,
+       &iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr,
+       &iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr,
+       &iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr,
+       &iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr,
        NULL,
 };
 
@@ -278,10 +166,18 @@ static const struct attribute_group ad7152_attribute_group = {
        .attrs = ad7152_attributes,
 };
 
-static const u8 ad7152_addresses[][3] = {
-       { AD7152_CH1_DATA_HIGH, AD7152_CH1_OFFS_HIGH, AD7152_CH1_GAIN_HIGH },
-       { AD7152_CH2_DATA_HIGH, AD7152_CH2_OFFS_HIGH, AD7152_CH2_GAIN_HIGH },
+static const u8 ad7152_addresses[][4] = {
+       { AD7152_CH1_DATA_HIGH, AD7152_CH1_OFFS_HIGH,
+         AD7152_CH1_GAIN_HIGH, AD7152_CH1_SETUP },
+       { AD7152_CH2_DATA_HIGH, AD7152_CH2_OFFS_HIGH,
+         AD7152_CH2_GAIN_HIGH, AD7152_CH2_SETUP },
+};
+
+/* Values are micro relative to pf base. */
+static const int ad7152_scale_table[] = {
+       488, 244, 122, 61
 };
+
 static int ad7152_write_raw(struct iio_dev *dev_info,
                            struct iio_chan_spec const *chan,
                            int val,
@@ -289,7 +185,7 @@ static int ad7152_write_raw(struct iio_dev *dev_info,
                            long mask)
 {
        struct ad7152_chip_info *chip = iio_priv(dev_info);
-       int ret;
+       int ret, i;
 
        switch (mask) {
        case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
@@ -313,7 +209,24 @@ static int ad7152_write_raw(struct iio_dev *dev_info,
                        return ret;
 
                return 0;
-
+       case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
+               if (val != 0)
+                       return -EINVAL;
+               for (i = 0; i < ARRAY_SIZE(ad7152_scale_table); i++)
+                       if (val2 <= ad7152_scale_table[i])
+                               break;
+               ret = i2c_smbus_read_byte_data(chip->client,
+                                       ad7152_addresses[chan->channel][3]);
+               if (ret < 0)
+                       return ret;
+               if ((ret & 0xC0) != i)
+                       ret = i2c_smbus_write_byte_data(chip->client,
+                                       ad7152_addresses[chan->channel][3],
+                                       (ret & ~0xC0) | i);
+               if (ret < 0)
+                       return ret;
+               else
+                       return 0;
        default:
                return -EINVAL;
        }
@@ -325,14 +238,34 @@ static int ad7152_read_raw(struct iio_dev *dev_info,
 {
        struct ad7152_chip_info *chip = iio_priv(dev_info);
        int ret;
-
+       u8 regval = 0;
        switch (mask) {
        case 0:
+               /* First set whether in differential mode */
+               if (chan->differential)
+                       regval = (1 << 5);
+
+               /* Make sure the channel is enabled */
+               if (chan->channel == 0)
+                       regval |= (1 << 4);
+               else
+                       regval |= (1 << 3);
+               /* Trigger a single read */
+               regval |= 0x02;
+               ret = i2c_smbus_write_byte_data(chip->client,
+                                       ad7152_addresses[chan->channel][3],
+                                       regval);
+               if (ret < 0)
+                       return ret;
+
+               msleep(60); /* Slowest conversion time */
+               /* Now read the actual register */
                ret = i2c_smbus_read_word_data(chip->client,
                                        ad7152_addresses[chan->channel][0]);
                if (ret < 0)
                        return ret;
                *val = ret;
+
                return IIO_VAL_INT;
        case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
                /* FIXME: Hmm. very small. it's 1+ 1/(2^16 *val) */
@@ -341,6 +274,7 @@ static int ad7152_read_raw(struct iio_dev *dev_info,
                if (ret < 0)
                        return ret;
                *val = ret;
+
                return IIO_VAL_INT;
        case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
                ret = i2c_smbus_read_word_data(chip->client,
@@ -348,7 +282,17 @@ static int ad7152_read_raw(struct iio_dev *dev_info,
                if (ret < 0)
                        return ret;
                *val = ret;
+
                return IIO_VAL_INT;
+       case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
+               ret = i2c_smbus_read_byte_data(chip->client,
+                                       ad7152_addresses[chan->channel][3]);
+               if (ret < 0)
+                       return ret;
+               *val = 0;
+               *val2 = ad7152_scale_table[ret >> 6];
+
+               return IIO_VAL_INT_PLUS_MICRO;
        default:
                return -EINVAL;
        };
@@ -366,13 +310,33 @@ static const struct iio_chan_spec ad7152_channels[] = {
                .indexed = 1,
                .channel = 0,
                .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
-               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
+               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE) |
+               (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
+       }, {
+               .type = IIO_CAPACITANCE,
+               .indexed = 1,
+               .channel = 1,
+               .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE) |
+               (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
+       }, {
+               .type = IIO_CAPACITANCE,
+               .differential = 1,
+               .indexed = 1,
+               .channel = 0,
+               .channel2 = 2,
+               .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE) |
+               (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
        }, {
                .type = IIO_CAPACITANCE,
+               .differential = 1,
                .indexed = 1,
                .channel = 1,
+               .channel2 = 3,
                .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
-               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
+               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE) |
+               (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
        }
 };
 /*
@@ -405,7 +369,7 @@ static int __devinit ad7152_probe(struct i2c_client *client,
        if (id->driver_data == 0)
                indio_dev->num_channels = ARRAY_SIZE(ad7152_channels);
        else
-               indio_dev->num_channels = 1;
+               indio_dev->num_channels = 2;
        indio_dev->num_channels = ARRAY_SIZE(ad7152_channels);
        indio_dev->modes = INDIO_DIRECT_MODE;