linux/drivers/iio/chemical/atlas-ph-sensor.c

510 lines
12 KiB
C

/*
* atlas-ph-sensor.c - Support for Atlas Scientific OEM pH-SM sensor
*
* Copyright (C) 2015 Matt Ranostay <mranostay@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/err.h>
#include <linux/irq.h>
#include <linux/irq_work.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/pm_runtime.h>
#define ATLAS_REGMAP_NAME "atlas_ph_regmap"
#define ATLAS_DRV_NAME "atlas_ph"
#define ATLAS_REG_DEV_TYPE 0x00
#define ATLAS_REG_DEV_VERSION 0x01
#define ATLAS_REG_INT_CONTROL 0x04
#define ATLAS_REG_INT_CONTROL_EN BIT(3)
#define ATLAS_REG_PWR_CONTROL 0x06
#define ATLAS_REG_CALIB_STATUS 0x0d
#define ATLAS_REG_CALIB_STATUS_MASK 0x07
#define ATLAS_REG_CALIB_STATUS_LOW BIT(0)
#define ATLAS_REG_CALIB_STATUS_MID BIT(1)
#define ATLAS_REG_CALIB_STATUS_HIGH BIT(2)
#define ATLAS_REG_TEMP_DATA 0x0e
#define ATLAS_REG_PH_DATA 0x16
#define ATLAS_PH_INT_TIME_IN_US 450000
struct atlas_data {
struct i2c_client *client;
struct iio_trigger *trig;
struct regmap *regmap;
struct irq_work work;
__be32 buffer[4]; /* 32-bit pH data + 32-bit pad + 64-bit timestamp */
};
static const struct regmap_range atlas_volatile_ranges[] = {
regmap_reg_range(ATLAS_REG_INT_CONTROL, ATLAS_REG_INT_CONTROL),
regmap_reg_range(ATLAS_REG_PH_DATA, ATLAS_REG_PH_DATA + 4),
};
static const struct regmap_access_table atlas_volatile_table = {
.yes_ranges = atlas_volatile_ranges,
.n_yes_ranges = ARRAY_SIZE(atlas_volatile_ranges),
};
static const struct regmap_config atlas_regmap_config = {
.name = ATLAS_REGMAP_NAME,
.reg_bits = 8,
.val_bits = 8,
.volatile_table = &atlas_volatile_table,
.max_register = ATLAS_REG_PH_DATA + 4,
.cache_type = REGCACHE_RBTREE,
};
static const struct iio_chan_spec atlas_channels[] = {
{
.type = IIO_PH,
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
.scan_index = 0,
.scan_type = {
.sign = 'u',
.realbits = 32,
.storagebits = 32,
.endianness = IIO_BE,
},
},
IIO_CHAN_SOFT_TIMESTAMP(1),
{
.type = IIO_TEMP,
.address = ATLAS_REG_TEMP_DATA,
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
.output = 1,
.scan_index = -1
},
};
static int atlas_set_powermode(struct atlas_data *data, int on)
{
return regmap_write(data->regmap, ATLAS_REG_PWR_CONTROL, on);
}
static int atlas_set_interrupt(struct atlas_data *data, bool state)
{
return regmap_update_bits(data->regmap, ATLAS_REG_INT_CONTROL,
ATLAS_REG_INT_CONTROL_EN,
state ? ATLAS_REG_INT_CONTROL_EN : 0);
}
static int atlas_buffer_postenable(struct iio_dev *indio_dev)
{
struct atlas_data *data = iio_priv(indio_dev);
int ret;
ret = iio_triggered_buffer_postenable(indio_dev);
if (ret)
return ret;
ret = pm_runtime_get_sync(&data->client->dev);
if (ret < 0) {
pm_runtime_put_noidle(&data->client->dev);
return ret;
}
return atlas_set_interrupt(data, true);
}
static int atlas_buffer_predisable(struct iio_dev *indio_dev)
{
struct atlas_data *data = iio_priv(indio_dev);
int ret;
ret = iio_triggered_buffer_predisable(indio_dev);
if (ret)
return ret;
ret = atlas_set_interrupt(data, false);
if (ret)
return ret;
pm_runtime_mark_last_busy(&data->client->dev);
return pm_runtime_put_autosuspend(&data->client->dev);
}
static const struct iio_trigger_ops atlas_interrupt_trigger_ops = {
.owner = THIS_MODULE,
};
static const struct iio_buffer_setup_ops atlas_buffer_setup_ops = {
.postenable = atlas_buffer_postenable,
.predisable = atlas_buffer_predisable,
};
static void atlas_work_handler(struct irq_work *work)
{
struct atlas_data *data = container_of(work, struct atlas_data, work);
iio_trigger_poll(data->trig);
}
static irqreturn_t atlas_trigger_handler(int irq, void *private)
{
struct iio_poll_func *pf = private;
struct iio_dev *indio_dev = pf->indio_dev;
struct atlas_data *data = iio_priv(indio_dev);
int ret;
ret = regmap_bulk_read(data->regmap, ATLAS_REG_PH_DATA,
(u8 *) &data->buffer, sizeof(data->buffer[0]));
if (!ret)
iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
iio_get_time_ns());
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static irqreturn_t atlas_interrupt_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct atlas_data *data = iio_priv(indio_dev);
irq_work_queue(&data->work);
return IRQ_HANDLED;
}
static int atlas_read_ph_measurement(struct atlas_data *data, __be32 *val)
{
struct device *dev = &data->client->dev;
int suspended = pm_runtime_suspended(dev);
int ret;
ret = pm_runtime_get_sync(dev);
if (ret < 0) {
pm_runtime_put_noidle(dev);
return ret;
}
if (suspended)
usleep_range(ATLAS_PH_INT_TIME_IN_US,
ATLAS_PH_INT_TIME_IN_US + 100000);
ret = regmap_bulk_read(data->regmap, ATLAS_REG_PH_DATA,
(u8 *) val, sizeof(*val));
pm_runtime_mark_last_busy(dev);
pm_runtime_put_autosuspend(dev);
return ret;
}
static int atlas_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct atlas_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW: {
int ret;
__be32 reg;
switch (chan->type) {
case IIO_TEMP:
ret = regmap_bulk_read(data->regmap, chan->address,
(u8 *) &reg, sizeof(reg));
break;
case IIO_PH:
mutex_lock(&indio_dev->mlock);
if (iio_buffer_enabled(indio_dev))
ret = -EBUSY;
else
ret = atlas_read_ph_measurement(data, &reg);
mutex_unlock(&indio_dev->mlock);
break;
default:
ret = -EINVAL;
}
if (!ret) {
*val = be32_to_cpu(reg);
ret = IIO_VAL_INT;
}
return ret;
}
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_TEMP:
*val = 1; /* 0.01 */
*val2 = 100;
break;
case IIO_PH:
*val = 1; /* 0.001 */
*val2 = 1000;
break;
default:
return -EINVAL;
}
return IIO_VAL_FRACTIONAL;
}
return -EINVAL;
}
static int atlas_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct atlas_data *data = iio_priv(indio_dev);
__be32 reg = cpu_to_be32(val);
if (val2 != 0 || val < 0 || val > 20000)
return -EINVAL;
if (mask != IIO_CHAN_INFO_RAW || chan->type != IIO_TEMP)
return -EINVAL;
return regmap_bulk_write(data->regmap, chan->address,
&reg, sizeof(reg));
}
static const struct iio_info atlas_info = {
.driver_module = THIS_MODULE,
.read_raw = atlas_read_raw,
.write_raw = atlas_write_raw,
};
static int atlas_check_calibration(struct atlas_data *data)
{
struct device *dev = &data->client->dev;
int ret;
unsigned int val;
ret = regmap_read(data->regmap, ATLAS_REG_CALIB_STATUS, &val);
if (ret)
return ret;
if (!(val & ATLAS_REG_CALIB_STATUS_MASK)) {
dev_warn(dev, "device has not been calibrated\n");
return 0;
}
if (!(val & ATLAS_REG_CALIB_STATUS_LOW))
dev_warn(dev, "device missing low point calibration\n");
if (!(val & ATLAS_REG_CALIB_STATUS_MID))
dev_warn(dev, "device missing mid point calibration\n");
if (!(val & ATLAS_REG_CALIB_STATUS_HIGH))
dev_warn(dev, "device missing high point calibration\n");
return 0;
};
static int atlas_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct atlas_data *data;
struct iio_trigger *trig;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
indio_dev->info = &atlas_info;
indio_dev->name = ATLAS_DRV_NAME;
indio_dev->channels = atlas_channels;
indio_dev->num_channels = ARRAY_SIZE(atlas_channels);
indio_dev->modes = INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE;
indio_dev->dev.parent = &client->dev;
trig = devm_iio_trigger_alloc(&client->dev, "%s-dev%d",
indio_dev->name, indio_dev->id);
if (!trig)
return -ENOMEM;
data = iio_priv(indio_dev);
data->client = client;
data->trig = trig;
trig->dev.parent = indio_dev->dev.parent;
trig->ops = &atlas_interrupt_trigger_ops;
iio_trigger_set_drvdata(trig, indio_dev);
i2c_set_clientdata(client, indio_dev);
data->regmap = devm_regmap_init_i2c(client, &atlas_regmap_config);
if (IS_ERR(data->regmap)) {
dev_err(&client->dev, "regmap initialization failed\n");
return PTR_ERR(data->regmap);
}
ret = pm_runtime_set_active(&client->dev);
if (ret)
return ret;
if (client->irq <= 0) {
dev_err(&client->dev, "no valid irq defined\n");
return -EINVAL;
}
ret = atlas_check_calibration(data);
if (ret)
return ret;
ret = iio_trigger_register(trig);
if (ret) {
dev_err(&client->dev, "failed to register trigger\n");
return ret;
}
ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
&atlas_trigger_handler, &atlas_buffer_setup_ops);
if (ret) {
dev_err(&client->dev, "cannot setup iio trigger\n");
goto unregister_trigger;
}
init_irq_work(&data->work, atlas_work_handler);
/* interrupt pin toggles on new conversion */
ret = devm_request_threaded_irq(&client->dev, client->irq,
NULL, atlas_interrupt_handler,
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
"atlas_irq",
indio_dev);
if (ret) {
dev_err(&client->dev, "request irq (%d) failed\n", client->irq);
goto unregister_buffer;
}
ret = atlas_set_powermode(data, 1);
if (ret) {
dev_err(&client->dev, "cannot power device on");
goto unregister_buffer;
}
pm_runtime_enable(&client->dev);
pm_runtime_set_autosuspend_delay(&client->dev, 2500);
pm_runtime_use_autosuspend(&client->dev);
ret = iio_device_register(indio_dev);
if (ret) {
dev_err(&client->dev, "unable to register device\n");
goto unregister_pm;
}
return 0;
unregister_pm:
pm_runtime_disable(&client->dev);
atlas_set_powermode(data, 0);
unregister_buffer:
iio_triggered_buffer_cleanup(indio_dev);
unregister_trigger:
iio_trigger_unregister(data->trig);
return ret;
}
static int atlas_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct atlas_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
iio_trigger_unregister(data->trig);
pm_runtime_disable(&client->dev);
pm_runtime_set_suspended(&client->dev);
pm_runtime_put_noidle(&client->dev);
return atlas_set_powermode(data, 0);
}
#ifdef CONFIG_PM
static int atlas_runtime_suspend(struct device *dev)
{
struct atlas_data *data =
iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
return atlas_set_powermode(data, 0);
}
static int atlas_runtime_resume(struct device *dev)
{
struct atlas_data *data =
iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
return atlas_set_powermode(data, 1);
}
#endif
static const struct dev_pm_ops atlas_pm_ops = {
SET_RUNTIME_PM_OPS(atlas_runtime_suspend,
atlas_runtime_resume, NULL)
};
static const struct i2c_device_id atlas_id[] = {
{ "atlas-ph-sm", 0 },
{}
};
MODULE_DEVICE_TABLE(i2c, atlas_id);
static const struct of_device_id atlas_dt_ids[] = {
{ .compatible = "atlas,ph-sm" },
{ }
};
MODULE_DEVICE_TABLE(of, atlas_dt_ids);
static struct i2c_driver atlas_driver = {
.driver = {
.name = ATLAS_DRV_NAME,
.of_match_table = of_match_ptr(atlas_dt_ids),
.pm = &atlas_pm_ops,
},
.probe = atlas_probe,
.remove = atlas_remove,
.id_table = atlas_id,
};
module_i2c_driver(atlas_driver);
MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
MODULE_DESCRIPTION("Atlas Scientific pH-SM sensor");
MODULE_LICENSE("GPL");