123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533 |
- /*
- * AD7152 capacitive sensor driver supporting AD7152/3
- *
- * Copyright 2010-2011a Analog Devices Inc.
- *
- * Licensed under the GPL-2 or later.
- */
- #include <linux/interrupt.h>
- #include <linux/device.h>
- #include <linux/kernel.h>
- #include <linux/slab.h>
- #include <linux/sysfs.h>
- #include <linux/i2c.h>
- #include <linux/module.h>
- #include <linux/delay.h>
- #include <linux/iio/iio.h>
- #include <linux/iio/sysfs.h>
- /*
- * TODO: Check compliance of calibbias with abi (units)
- */
- /*
- * AD7152 registers definition
- */
- #define AD7152_REG_STATUS 0
- #define AD7152_REG_CH1_DATA_HIGH 1
- #define AD7152_REG_CH2_DATA_HIGH 3
- #define AD7152_REG_CH1_OFFS_HIGH 5
- #define AD7152_REG_CH2_OFFS_HIGH 7
- #define AD7152_REG_CH1_GAIN_HIGH 9
- #define AD7152_REG_CH1_SETUP 11
- #define AD7152_REG_CH2_GAIN_HIGH 12
- #define AD7152_REG_CH2_SETUP 14
- #define AD7152_REG_CFG 15
- #define AD7152_REG_RESEVERD 16
- #define AD7152_REG_CAPDAC_POS 17
- #define AD7152_REG_CAPDAC_NEG 18
- #define AD7152_REG_CFG2 26
- /* Status Register Bit Designations (AD7152_REG_STATUS) */
- #define AD7152_STATUS_RDY1 (1 << 0)
- #define AD7152_STATUS_RDY2 (1 << 1)
- #define AD7152_STATUS_C1C2 (1 << 2)
- #define AD7152_STATUS_PWDN (1 << 7)
- /* Setup Register Bit Designations (AD7152_REG_CHx_SETUP) */
- #define AD7152_SETUP_CAPDIFF (1 << 5)
- #define AD7152_SETUP_RANGE_2pF (0 << 6)
- #define AD7152_SETUP_RANGE_0_5pF (1 << 6)
- #define AD7152_SETUP_RANGE_1pF (2 << 6)
- #define AD7152_SETUP_RANGE_4pF (3 << 6)
- #define AD7152_SETUP_RANGE(x) ((x) << 6)
- /* Config Register Bit Designations (AD7152_REG_CFG) */
- #define AD7152_CONF_CH2EN (1 << 3)
- #define AD7152_CONF_CH1EN (1 << 4)
- #define AD7152_CONF_MODE_IDLE (0 << 0)
- #define AD7152_CONF_MODE_CONT_CONV (1 << 0)
- #define AD7152_CONF_MODE_SINGLE_CONV (2 << 0)
- #define AD7152_CONF_MODE_OFFS_CAL (5 << 0)
- #define AD7152_CONF_MODE_GAIN_CAL (6 << 0)
- /* Capdac Register Bit Designations (AD7152_REG_CAPDAC_XXX) */
- #define AD7152_CAPDAC_DACEN (1 << 7)
- #define AD7152_CAPDAC_DACP(x) ((x) & 0x1F)
- /* CFG2 Register Bit Designations (AD7152_REG_CFG2) */
- #define AD7152_CFG2_OSR(x) (((x) & 0x3) << 4)
- enum {
- AD7152_DATA,
- AD7152_OFFS,
- AD7152_GAIN,
- AD7152_SETUP
- };
- /*
- * struct ad7152_chip_info - chip specific information
- */
- struct ad7152_chip_info {
- struct i2c_client *client;
- /*
- * Capacitive channel digital filter setup;
- * conversion time/update rate setup per channel
- */
- u8 filter_rate_setup;
- u8 setup[2];
- };
- 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 *indio_dev = dev_to_iio_dev(dev);
- struct ad7152_chip_info *chip = iio_priv(indio_dev);
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- bool doit;
- int ret, timeout = 10;
- ret = strtobool(buf, &doit);
- if (ret < 0)
- return ret;
- if (!doit)
- return 0;
- if (this_attr->address == 0)
- regval |= AD7152_CONF_CH1EN;
- else
- regval |= AD7152_CONF_CH2EN;
- mutex_lock(&indio_dev->mlock);
- ret = i2c_smbus_write_byte_data(chip->client, AD7152_REG_CFG, regval);
- if (ret < 0) {
- mutex_unlock(&indio_dev->mlock);
- return ret;
- }
- do {
- mdelay(20);
- ret = i2c_smbus_read_byte_data(chip->client, AD7152_REG_CFG);
- if (ret < 0) {
- mutex_unlock(&indio_dev->mlock);
- return ret;
- }
- } while ((ret == regval) && timeout--);
- mutex_unlock(&indio_dev->mlock);
- return len;
- }
- static ssize_t ad7152_start_offset_calib(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
- {
- return ad7152_start_calib(dev, attr, buf, len,
- AD7152_CONF_MODE_OFFS_CAL);
- }
- static ssize_t ad7152_start_gain_calib(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
- {
- return ad7152_start_calib(dev, attr, buf, len,
- AD7152_CONF_MODE_GAIN_CAL);
- }
- 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);
- /* Values are Update Rate (Hz), Conversion Time (ms) + 1*/
- static const unsigned char ad7152_filter_rate_table[][2] = {
- {200, 5 + 1}, {50, 20 + 1}, {20, 50 + 1}, {17, 60 + 1},
- };
- static ssize_t ad7152_show_filter_rate_setup(struct device *dev,
- struct device_attribute *attr,
- char *buf)
- {
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct ad7152_chip_info *chip = iio_priv(indio_dev);
- return sprintf(buf, "%d\n",
- ad7152_filter_rate_table[chip->filter_rate_setup][0]);
- }
- static ssize_t ad7152_store_filter_rate_setup(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
- {
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct ad7152_chip_info *chip = iio_priv(indio_dev);
- u8 data;
- int ret, i;
- ret = kstrtou8(buf, 10, &data);
- if (ret < 0)
- return ret;
- for (i = 0; i < ARRAY_SIZE(ad7152_filter_rate_table); i++)
- if (data >= ad7152_filter_rate_table[i][0])
- break;
- if (i >= ARRAY_SIZE(ad7152_filter_rate_table))
- i = ARRAY_SIZE(ad7152_filter_rate_table) - 1;
- mutex_lock(&indio_dev->mlock);
- ret = i2c_smbus_write_byte_data(chip->client,
- AD7152_REG_CFG2, AD7152_CFG2_OSR(i));
- if (ret < 0) {
- mutex_unlock(&indio_dev->mlock);
- return ret;
- }
- chip->filter_rate_setup = i;
- mutex_unlock(&indio_dev->mlock);
- return len;
- }
- static IIO_DEV_ATTR_SAMP_FREQ(S_IRUGO | S_IWUSR,
- ad7152_show_filter_rate_setup,
- ad7152_store_filter_rate_setup);
- static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("200 50 20 17");
- static IIO_CONST_ATTR(in_capacitance_scale_available,
- "0.000061050 0.000030525 0.000015263 0.000007631");
- static struct attribute *ad7152_attributes[] = {
- &iio_dev_attr_sampling_frequency.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,
- &iio_const_attr_in_capacitance_scale_available.dev_attr.attr,
- &iio_const_attr_sampling_frequency_available.dev_attr.attr,
- NULL,
- };
- static const struct attribute_group ad7152_attribute_group = {
- .attrs = ad7152_attributes,
- };
- static const u8 ad7152_addresses[][4] = {
- { AD7152_REG_CH1_DATA_HIGH, AD7152_REG_CH1_OFFS_HIGH,
- AD7152_REG_CH1_GAIN_HIGH, AD7152_REG_CH1_SETUP },
- { AD7152_REG_CH2_DATA_HIGH, AD7152_REG_CH2_OFFS_HIGH,
- AD7152_REG_CH2_GAIN_HIGH, AD7152_REG_CH2_SETUP },
- };
- /* Values are nano relative to pf base. */
- static const int ad7152_scale_table[] = {
- 30525, 7631, 15263, 61050
- };
- static int ad7152_write_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int val,
- int val2,
- long mask)
- {
- struct ad7152_chip_info *chip = iio_priv(indio_dev);
- int ret, i;
- mutex_lock(&indio_dev->mlock);
- switch (mask) {
- case IIO_CHAN_INFO_CALIBSCALE:
- if (val != 1) {
- ret = -EINVAL;
- goto out;
- }
- val = (val2 * 1024) / 15625;
- ret = i2c_smbus_write_word_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_GAIN],
- swab16(val));
- if (ret < 0)
- goto out;
- ret = 0;
- break;
- case IIO_CHAN_INFO_CALIBBIAS:
- if ((val < 0) | (val > 0xFFFF)) {
- ret = -EINVAL;
- goto out;
- }
- ret = i2c_smbus_write_word_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_OFFS],
- swab16(val));
- if (ret < 0)
- goto out;
- ret = 0;
- break;
- case IIO_CHAN_INFO_SCALE:
- if (val) {
- ret = -EINVAL;
- goto out;
- }
- for (i = 0; i < ARRAY_SIZE(ad7152_scale_table); i++)
- if (val2 == ad7152_scale_table[i])
- break;
- chip->setup[chan->channel] &= ~AD7152_SETUP_RANGE_4pF;
- chip->setup[chan->channel] |= AD7152_SETUP_RANGE(i);
- ret = i2c_smbus_write_byte_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_SETUP],
- chip->setup[chan->channel]);
- if (ret < 0)
- goto out;
- ret = 0;
- break;
- default:
- ret = -EINVAL;
- }
- out:
- mutex_unlock(&indio_dev->mlock);
- return ret;
- }
- static int ad7152_read_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val, int *val2,
- long mask)
- {
- struct ad7152_chip_info *chip = iio_priv(indio_dev);
- int ret;
- u8 regval = 0;
- mutex_lock(&indio_dev->mlock);
- switch (mask) {
- case IIO_CHAN_INFO_RAW:
- /* First set whether in differential mode */
- regval = chip->setup[chan->channel];
- if (chan->differential)
- chip->setup[chan->channel] |= AD7152_SETUP_CAPDIFF;
- else
- chip->setup[chan->channel] &= ~AD7152_SETUP_CAPDIFF;
- if (regval != chip->setup[chan->channel]) {
- ret = i2c_smbus_write_byte_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_SETUP],
- chip->setup[chan->channel]);
- if (ret < 0)
- goto out;
- }
- /* Make sure the channel is enabled */
- if (chan->channel == 0)
- regval = AD7152_CONF_CH1EN;
- else
- regval = AD7152_CONF_CH2EN;
- /* Trigger a single read */
- regval |= AD7152_CONF_MODE_SINGLE_CONV;
- ret = i2c_smbus_write_byte_data(chip->client, AD7152_REG_CFG,
- regval);
- if (ret < 0)
- goto out;
- msleep(ad7152_filter_rate_table[chip->filter_rate_setup][1]);
- /* Now read the actual register */
- ret = i2c_smbus_read_word_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_DATA]);
- if (ret < 0)
- goto out;
- *val = swab16(ret);
- if (chan->differential)
- *val -= 0x8000;
- ret = IIO_VAL_INT;
- break;
- case IIO_CHAN_INFO_CALIBSCALE:
- ret = i2c_smbus_read_word_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_GAIN]);
- if (ret < 0)
- goto out;
- /* 1 + gain_val / 2^16 */
- *val = 1;
- *val2 = (15625 * swab16(ret)) / 1024;
- ret = IIO_VAL_INT_PLUS_MICRO;
- break;
- case IIO_CHAN_INFO_CALIBBIAS:
- ret = i2c_smbus_read_word_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_OFFS]);
- if (ret < 0)
- goto out;
- *val = swab16(ret);
- ret = IIO_VAL_INT;
- break;
- case IIO_CHAN_INFO_SCALE:
- ret = i2c_smbus_read_byte_data(chip->client,
- ad7152_addresses[chan->channel][AD7152_SETUP]);
- if (ret < 0)
- goto out;
- *val = 0;
- *val2 = ad7152_scale_table[ret >> 6];
- ret = IIO_VAL_INT_PLUS_NANO;
- break;
- default:
- ret = -EINVAL;
- }
- out:
- mutex_unlock(&indio_dev->mlock);
- return ret;
- }
- static int ad7152_write_raw_get_fmt(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- long mask)
- {
- switch (mask) {
- case IIO_CHAN_INFO_SCALE:
- return IIO_VAL_INT_PLUS_NANO;
- default:
- return IIO_VAL_INT_PLUS_MICRO;
- }
- }
- static const struct iio_info ad7152_info = {
- .attrs = &ad7152_attribute_group,
- .read_raw = &ad7152_read_raw,
- .write_raw = &ad7152_write_raw,
- .write_raw_get_fmt = &ad7152_write_raw_get_fmt,
- .driver_module = THIS_MODULE,
- };
- static const struct iio_chan_spec ad7152_channels[] = {
- {
- .type = IIO_CAPACITANCE,
- .indexed = 1,
- .channel = 0,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_CALIBSCALE) |
- BIT(IIO_CHAN_INFO_CALIBBIAS) |
- BIT(IIO_CHAN_INFO_SCALE),
- }, {
- .type = IIO_CAPACITANCE,
- .differential = 1,
- .indexed = 1,
- .channel = 0,
- .channel2 = 2,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_CALIBSCALE) |
- BIT(IIO_CHAN_INFO_CALIBBIAS) |
- BIT(IIO_CHAN_INFO_SCALE),
- }, {
- .type = IIO_CAPACITANCE,
- .indexed = 1,
- .channel = 1,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_CALIBSCALE) |
- BIT(IIO_CHAN_INFO_CALIBBIAS) |
- BIT(IIO_CHAN_INFO_SCALE),
- }, {
- .type = IIO_CAPACITANCE,
- .differential = 1,
- .indexed = 1,
- .channel = 1,
- .channel2 = 3,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_CALIBSCALE) |
- BIT(IIO_CHAN_INFO_CALIBBIAS) |
- BIT(IIO_CHAN_INFO_SCALE),
- }
- };
- /*
- * device probe and remove
- */
- static int ad7152_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
- {
- int ret = 0;
- struct ad7152_chip_info *chip;
- struct iio_dev *indio_dev;
- indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
- if (!indio_dev)
- return -ENOMEM;
- chip = iio_priv(indio_dev);
- /* this is only used for device removal purposes */
- i2c_set_clientdata(client, indio_dev);
- chip->client = client;
- /* Establish that the iio_dev is a child of the i2c device */
- indio_dev->name = id->name;
- indio_dev->dev.parent = &client->dev;
- indio_dev->info = &ad7152_info;
- indio_dev->channels = ad7152_channels;
- if (id->driver_data == 0)
- indio_dev->num_channels = ARRAY_SIZE(ad7152_channels);
- else
- indio_dev->num_channels = 2;
- indio_dev->num_channels = ARRAY_SIZE(ad7152_channels);
- indio_dev->modes = INDIO_DIRECT_MODE;
- ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
- if (ret)
- return ret;
- dev_err(&client->dev, "%s capacitive sensor registered\n", id->name);
- return 0;
- }
- static const struct i2c_device_id ad7152_id[] = {
- { "ad7152", 0 },
- { "ad7153", 1 },
- {}
- };
- MODULE_DEVICE_TABLE(i2c, ad7152_id);
- static struct i2c_driver ad7152_driver = {
- .driver = {
- .name = KBUILD_MODNAME,
- },
- .probe = ad7152_probe,
- .id_table = ad7152_id,
- };
- module_i2c_driver(ad7152_driver);
- MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
- MODULE_DESCRIPTION("Analog Devices AD7152/3 capacitive sensor driver");
- MODULE_LICENSE("GPL v2");
|