diff options
Diffstat (limited to 'drivers/iio/chemical/atlas-ph-sensor.c')
| -rw-r--r-- | drivers/iio/chemical/atlas-ph-sensor.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/drivers/iio/chemical/atlas-ph-sensor.c b/drivers/iio/chemical/atlas-ph-sensor.c new file mode 100644 index 000000000..62b37cd8f --- /dev/null +++ b/drivers/iio/chemical/atlas-ph-sensor.c @@ -0,0 +1,509 @@ +/* + * 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 *) ®, 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, ®); + + 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, + ®, 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"); |