/*
* iio/adc/ad799x.c
* Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc.
*
* based on iio/adc/max1363
* Copyright (C) 2008-2010 Jonathan Cameron
*
* based on linux/drivers/i2c/chips/max123x
* Copyright (C) 2002-2004 Stefan Eletzhofer
*
* based on linux/drivers/acron/char/pcf8583.c
* Copyright (C) 2000 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* ad799x.c
*
* Support for ad7991, ad7995, ad7999, ad7992, ad7993, ad7994, ad7997,
* ad7998 and similar chips.
*
*/
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/sysfs.h>
#include <linux/i2c.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#define AD799X_CHANNEL_SHIFT 4
#define AD799X_STORAGEBITS 16
/*
* AD7991, AD7995 and AD7999 defines
*/
#define AD7991_REF_SEL 0x08
#define AD7991_FLTR 0x04
#define AD7991_BIT_TRIAL_DELAY 0x02
#define AD7991_SAMPLE_DELAY 0x01
/*
* AD7992, AD7993, AD7994, AD7997 and AD7998 defines
*/
#define AD7998_FLTR 0x08
#define AD7998_ALERT_EN 0x04
#define AD7998_BUSY_ALERT 0x02
#define AD7998_BUSY_ALERT_POL 0x01
#define AD7998_CONV_RES_REG 0x0
#define AD7998_ALERT_STAT_REG 0x1
#define AD7998_CONF_REG 0x2
#define AD7998_CYCLE_TMR_REG 0x3
#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
#define AD7998_CYC_TCONF_32 0x1
#define AD7998_CYC_TCONF_64 0x2
#define AD7998_CYC_TCONF_128 0x3
#define AD7998_CYC_TCONF_256 0x4
#define AD7998_CYC_TCONF_512 0x5
#define AD7998_CYC_TCONF_1024 0x6
#define AD7998_CYC_TCONF_2048 0x7
#define AD7998_ALERT_STAT_CLEAR 0xFF
/*
* AD7997 and AD7997 defines
*/
#define AD7997_8_READ_SINGLE 0x80
#define AD7997_8_READ_SEQUENCE 0x70
/* TODO: move this into a common header */
#define RES_MASK(bits) ((1 << (bits)) - 1)
enum {
ad7991,
ad7995,
ad7999,
ad7992,
ad7993,
ad7994,
ad7997,
ad7998
};
/**
* struct ad799x_chip_info - chip specific information
* @channel: channel specification
* @num_channels: number of channels
* @monitor_mode: whether the chip supports monitor interrupts
* @default_config: device default configuration
* @event_attrs: pointer to the monitor event attribute group
*/
struct ad799x_chip_info {
struct iio_chan_spec channel[9];
int num_channels;
u16 default_config;
const struct iio_info *info;
};
struct ad799x_state {
struct i2c_client *client;
const struct ad799x_chip_info *chip_info;
struct regulator *reg;
struct regulator *vref;
unsigned id;
u16 config;
u8 *rx_buf;
unsigned int transfer_size;
};
/**
* ad799x_trigger_handler() bh of trigger launched polling to ring buffer
*
* Currently there is no option in this driver to disable the saving of
* timestamps within the ring.
**/
static irqreturn_t ad799x_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct ad799x_state *st = iio_priv(indio_dev);
int b_sent;
u8 cmd;
switch (st->id) {
case ad7991:
case ad7995:
case ad7999:
cmd = st->config |
(*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT);
break;
case ad7992:
case ad7993:
case ad7994:
cmd = (*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT) |
AD7998_CONV_RES_REG;
break;
case ad7997:
case ad7998:
cmd = AD7997_8_READ_SEQUENCE | AD7998_CONV_RES_REG;
break;
default:
cmd = 0;
}
b_sent = i2c_smbus_read_i2c_block_data(st->client,
cmd, st->transfer_size, st->rx_buf);
if (b_sent < 0)
goto out;
iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
iio_get_time_ns());
out:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
/*
* ad799x register access by I2C
*/
static int ad799x_i2c_read16(struct ad799x_state *st, u8 reg, u16 *data)
{
struct i2c_client *client = st->client;
int ret = 0;
ret = i2c_smbus_read_word_swapped(client, reg);
if (ret < 0) {
dev_err(&client->dev, "I2C read error\n");
return ret;
}
*data = (u16)ret;
return 0;
}
static int ad799x_i2c_read8(struct ad799x_state *st, u8 reg, u8 *data)
{
struct i2c_client *client = st->client;
int ret = 0;
ret = i2c_smbus_read_byte_data(client, reg);
if (ret < 0) {
dev_err(&client->dev, "I2C read error\n");
return ret;
}
*data = (u8)ret;
return 0;
}
static int ad799x_i2c_write16(struct ad799x_state *st, u8 reg, u16 data)
{
struct i2c_client *client = st->client;
int ret = 0;
ret = i2c_smbus_write_word_swapped(client, reg, data);
if (ret < 0)
dev_err(&client->dev, "I2C write error\n");
return ret;
}
static int ad799x_i2c_write8(struct ad799x_state *st, u8 reg, u8 data)
{
struct i2c_client *client = st->client;
int ret = 0;
ret = i2c_smbus_write_byte_data(client, reg, data);
if (ret < 0)
dev_err(&client->dev, "I2C write error\n");
return ret;
}
static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *scan_mask)
{
struct ad799x_state *st = iio_priv(indio_dev);
kfree(st->rx_buf);
st->rx_buf = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
if (!st->rx_buf)
return -ENOMEM;
st->transfer_size = bitmap_weight(scan_mask, indio_dev->masklength) * 2;
switch (st->id) {
case ad7997:
case ad7998:
return ad799x_i2c_write16(st, AD7998_CONF_REG,
st->config | (*scan_mask << AD799X_CHANNEL_SHIFT));
default:
break;
}
return 0;
}
static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
{
u16 rxbuf;
u8 cmd;
int ret;
switch (st->id) {
case ad7991:
case ad7995:
case ad7999:
cmd = st->config | ((1 << ch) << AD799X_CHANNEL_SHIFT);
break;
case ad7992:
case ad7993:
case ad7994:
cmd = (1 << ch) << AD799X_CHANNEL_SHIFT;
break;
case ad7997:
case ad7998:
cmd = (ch << AD799X_CHANNEL_SHIFT) | AD7997_8_READ_SINGLE;
break;
default:
return -EINVAL;
}
ret = ad799x_i2c_read16(st, cmd, &rxbuf);
if (ret < 0)
return ret;
return rxbuf;
}
static int ad799x_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
int ret;
struct ad799x_state *st = iio_priv(indio_dev);
switch (m) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&indio_dev->mlock);
if (iio_buffer_enabled(indio_dev))
ret = -EBUSY;
else
ret = ad799x_scan_direct(st, chan->scan_index);
mutex_unlock(&indio_dev->mlock);
if (ret < 0)
return ret;
*val = (ret >> chan->scan_type.shift) &
RES_MASK(chan->scan_type.realbits);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
ret = regulator_get_voltage(st->vref);
if (ret < 0)
return ret;
*val = ret / 1000;
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
}
return -EINVAL;
}
static const unsigned int ad7998_frequencies[] = {
[AD7998_CYC_DIS] = 0,
[AD7998_CYC_TCONF_32] = 15625,
[AD7998_CYC_TCONF_64] = 7812,
[AD7998_CYC_TCONF_128] = 3906,
[AD7998_CYC_TCONF_512] = 976,
[AD7998_CYC_TCONF_1024] = 488,
[AD7998_CYC_TCONF_2048] = 244,
};
static ssize_t ad799x_read_frequency(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad799x_state *st = iio_priv(indio_dev);
int ret;
u8 val;
ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &val);
if (ret)
return ret;
val &= AD7998_CYC_MASK;
return sprintf(buf, "%u\n", ad7998_frequencies[val]);
}
static ssize_t ad799x_write_frequency(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad799x_state *st = iio_priv(indio_dev);
long val;
int ret, i;
u8 t;
ret = kstrtol(buf, 10, &val);
if (ret)
return ret;
mutex_lock(&indio_dev->mlock);
ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &t);
if (ret)
goto error_ret_mutex;
/* Wipe the bits clean */
t &= ~AD7998_CYC_MASK;
for (i = 0; i < ARRAY_SIZE(ad7998_frequencies); i++)
if (val == ad7998_frequencies[i])
break;
if (i == ARRAY_SIZE(ad7998_frequencies)) {
ret = -EINVAL;
goto error_ret_mutex;
}
t |= i;
ret = ad799x_i2c_write8(st, AD7998_CYCLE_TMR_REG, t);
error_ret_mutex:
mutex_unlock(&indio_dev->mlock);
return ret ? ret : len;
}
static int ad799x_read_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir)
{
return 1;
}
static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
enum iio_event_direction dir,
enum iio_event_info info)
{
switch (info) {
case IIO_EV_INFO_VALUE:
if (dir == IIO_EV_DIR_FALLING)
return AD7998_DATALOW_REG(chan->channel);
else
return AD7998_DATAHIGH_REG(chan->channel);
case IIO_EV_INFO_HYSTERESIS:
return AD7998_HYST_REG(chan->channel);
default:
return -EINVAL;
}
return 0;
}
static int ad799x_write_event_value(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
enum iio_event_info info,
int val, int val2)
{
int ret;
struct ad799x_state *st = iio_priv(indio_dev);
if (val < 0 || val > RES_MASK(chan->scan_type.realbits))
return -EINVAL;
mutex_lock(&indio_dev->mlock);
ret = ad799x_i2c_write16(st, ad799x_threshold_reg(chan, dir, info),
val << chan->scan_type.shift);
mutex_unlock(&indio_dev->mlock);
return ret;
}
static int ad799x_read_event_value(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
enum iio_event_info info,
int *val, int *val2)
{
int ret;
struct ad799x_state *st = iio_priv(indio_dev);
u16 valin;
mutex_lock(&indio_dev->mlock);
ret = ad799x_i2c_read16(st, ad799x_threshold_reg(chan, dir, info),
&valin);
mutex_unlock(&indio_dev->mlock);
if (ret < 0)
return ret;
*val = (valin >> chan->scan_type.shift) &
RES_MASK(chan->scan_type.realbits);
return IIO_VAL_INT;
}
static irqreturn_t ad799x_event_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct ad799x_state *st = iio_priv(private);
u8 status;
int i, ret;
ret = ad799x_i2c_read8(st, AD7998_ALERT_STAT_REG, &status);
if (ret)
goto done;
if (!status)
goto done;
ad799x_i2c_write8(st, AD7998_ALERT_STAT_REG, AD7998_ALERT_STAT_CLEAR);
for (i = 0; i < 8; i++) {
if (status & (1 << i))
iio_push_event(indio_dev,
i & 0x1 ?
IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
(i >> 1),
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING) :
IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
(i >> 1),
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_FALLING),
iio_get_time_ns());
}
done:
return IRQ_HANDLED;
}
static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
ad799x_read_frequency,
ad799x_write_frequency);
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("15625 7812 3906 1953 976 488 244 0");
static struct attribute *ad799x_event_attributes[] = {
&iio_dev_attr_sampling_frequency.dev_attr.attr,
&iio_const_attr_sampling_frequency_available.dev_attr.attr,
NULL,
};
static struct attribute_group ad799x_event_attrs_group = {
.attrs = ad799x_event_attributes,
.name = "events",
};
static const struct iio_info ad7991_info = {
.read_raw = &ad799x_read_raw,
.driver_module = THIS_MODULE,
};
static const struct iio_info ad7993_4_7_8_info = {
.read_raw = &ad799x_read_raw,
.event_attrs = &ad799x_event_attrs_group,
.read_event_config = &ad799x_read_event_config,
.read_event_value = &ad799x_read_event_value,
.write_event_value = &ad799x_write_event_value,
.driver_module = THIS_MODULE,
.update_scan_mode = ad7997_8_update_scan_mode,
};
static const struct iio_event_spec ad799x_events[] = {
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_RISING,
.mask_separate = BIT(IIO_EV_INFO_VALUE) |
BIT(IIO_EV_INFO_ENABLE),
}, {
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_FALLING,
.mask_separate = BIT(IIO_EV_INFO_VALUE) |
BIT(IIO_EV_INFO_ENABLE),
}, {
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_EITHER,
.mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
},
};
#define _AD799X_CHANNEL(_index, _realbits, _ev_spec, _num_ev_spec) { \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = (_index), \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.scan_index = (_index), \
.scan_type = { \
.sign = 'u', \
.realbits = (_realbits), \
.storagebits = 16, \
.shift = 12 - (_realbits), \
.endianness = IIO_BE, \
}, \
.event_spec = _ev_spec, \
.num_event_specs = _num_ev_spec, \
}
#define AD799X_CHANNEL(_index, _realbits) \
_AD799X_CHANNEL(_index, _realbits, NULL, 0)
#define AD799X_CHANNEL_WITH_EVENTS(_index, _realbits) \
_AD799X_CHANNEL(_index, _realbits, ad799x_events, \
ARRAY_SIZE(ad799x_events))
static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
[ad7991] = {
.channel = {
AD799X_CHANNEL(0, 12),
AD799X_CHANNEL(1, 12),
AD799X_CHANNEL(2, 12),
AD799X_CHANNEL(3, 12),
IIO_CHAN_SOFT_TIMESTAMP(4),
},
.num_channels = 5,
.info = &ad7991_info,
},
[ad7995] = {
.channel = {
AD799X_CHANNEL(0, 10),
AD799X_CHANNEL(1, 10),
AD799X_CHANNEL(2, 10),
AD799X_CHANNEL(3, 10),
IIO_CHAN_SOFT_TIMESTAMP(4),
},
.num_channels = 5,
.info = &ad7991_info,
},
[ad7999] = {
.channel = {
AD799X_CHANNEL(0, 8),
AD799X_CHANNEL(1, 8),
AD799X_CHANNEL(2, 8),
AD799X_CHANNEL(3, 8),
IIO_CHAN_SOFT_TIMESTAMP(4),
},
.num_channels = 5,
.info = &ad7991_info,
},
[ad7992] = {
.channel = {
AD799X_CHANNEL_WITH_EVENTS(0, 12),
AD799X_CHANNEL_WITH_EVENTS(1, 12),
IIO_CHAN_SOFT_TIMESTAMP(3),
},
.num_channels = 3,
.default_config = AD7998_ALERT_EN,
.info = &ad7993_4_7_8_info,
},
[ad7993] = {
.channel = {
AD799X_CHANNEL_WITH_EVENTS(0, 10),
AD799X_CHANNEL_WITH_EVENTS(1, 10),
AD799X_CHANNEL_WITH_EVENTS(2, 10),
AD799X_CHANNEL_WITH_EVENTS(3, 10),
IIO_CHAN_SOFT_TIMESTAMP(4),
},
.num_channels = 5,
.default_config = AD7998_ALERT_EN,
.info = &ad7993_4_7_8_info,
},
[ad7994] = {
.channel = {
AD799X_CHANNEL_WITH_EVENTS(0, 12),
AD799X_CHANNEL_WITH_EVENTS(1, 12),
AD799X_CHANNEL_WITH_EVENTS(2, 12),
AD799X_CHANNEL_WITH_EVENTS(3, 12),
IIO_CHAN_SOFT_TIMESTAMP(4),
},
.num_channels = 5,
.default_config = AD7998_ALERT_EN,
.info = &ad7993_4_7_8_info,
},
[ad7997] = {
.channel = {
AD799X_CHANNEL_WITH_EVENTS(0, 10),
AD799X_CHANNEL_WITH_EVENTS(1, 10),
AD799X_CHANNEL_WITH_EVENTS(2, 10),
AD799X_CHANNEL_WITH_EVENTS(3, 10),
AD799X_CHANNEL(4, 10),
AD799X_CHANNEL(5, 10),
AD799X_CHANNEL(6, 10),
AD799X_CHANNEL(7, 10),
IIO_CHAN_SOFT_TIMESTAMP(8),
},
.num_channels = 9,
.default_config = AD7998_ALERT_EN,
.info = &ad7993_4_7_8_info,
},
[ad7998] = {
.channel = {
AD799X_CHANNEL_WITH_EVENTS(0, 12),
AD799X_CHANNEL_WITH_EVENTS(1, 12),
AD799X_CHANNEL_WITH_EVENTS(2, 12),
AD799X_CHANNEL_WITH_EVENTS(3, 12),
AD799X_CHANNEL(4, 12),
AD799X_CHANNEL(5, 12),
AD799X_CHANNEL(6, 12),
AD799X_CHANNEL(7, 12),
IIO_CHAN_SOFT_TIMESTAMP(8),
},
.num_channels = 9,
.default_config = AD7998_ALERT_EN,
.info = &ad7993_4_7_8_info,
},
};
static int ad799x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct ad799x_state *st;
struct iio_dev *indio_dev;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
if (indio_dev == NULL)
return -ENOMEM;
st = iio_priv(indio_dev);
/* this is only used for device removal purposes */
i2c_set_clientdata(client, indio_dev);
st->id = id->driver_data;
st->chip_info = &ad799x_chip_info_tbl[st->id];
st->config = st->chip_info->default_config;
/* TODO: Add pdata options for filtering and bit delay */
st->reg = devm_regulator_get(&client->dev, "vcc");
if (IS_ERR(st->reg))
return PTR_ERR(st->reg);
ret = regulator_enable(st->reg);
if (ret)
return ret;
st->vref = devm_regulator_get(&client->dev, "vref");
if (IS_ERR(st->vref)) {
ret = PTR_ERR(st->vref);
goto error_disable_reg;
}
ret = regulator_enable(st->vref);
if (ret)
goto error_disable_reg;
st->client = client;
indio_dev->dev.parent = &client->dev;
indio_dev->name = id->name;
indio_dev->info = st->chip_info->info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = st->chip_info->channel;
indio_dev->num_channels = st->chip_info->num_channels;
ret = iio_triggered_buffer_setup(indio_dev, NULL,
&ad799x_trigger_handler, NULL);
if (ret)
goto error_disable_vref;
if (client->irq > 0) {
ret = devm_request_threaded_irq(&client->dev,
client->irq,
NULL,
ad799x_event_handler,
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
client->name,
indio_dev);
if (ret)
goto error_cleanup_ring;
}
ret = iio_device_register(indio_dev);
if (ret)
goto error_cleanup_ring;
return 0;
error_cleanup_ring:
iio_triggered_buffer_cleanup(indio_dev);
error_disable_vref:
regulator_disable(st->vref);
error_disable_reg:
regulator_disable(st->reg);
return ret;
}
static int ad799x_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct ad799x_state *st = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
regulator_disable(st->vref);
regulator_disable(st->reg);
kfree(st->rx_buf);
return 0;
}
static const struct i2c_device_id ad799x_id[] = {
{ "ad7991", ad7991 },
{ "ad7995", ad7995 },
{ "ad7999", ad7999 },
{ "ad7992", ad7992 },
{ "ad7993", ad7993 },
{ "ad7994", ad7994 },
{ "ad7997", ad7997 },
{ "ad7998", ad7998 },
{}
};
MODULE_DEVICE_TABLE(i2c, ad799x_id);
static struct i2c_driver ad799x_driver = {
.driver = {
.name = "ad799x",
},
.probe = ad799x_probe,
.remove = ad799x_remove,
.id_table = ad799x_id,
};
module_i2c_driver(ad799x_driver);
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD799x ADC");
MODULE_LICENSE("GPL v2");
