--- /dev/null
+/*
+ * 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_CALIB_STATUS, ATLAS_REG_CALIB_STATUS),
+ regmap_reg_range(ATLAS_REG_TEMP_DATA, ATLAS_REG_TEMP_DATA + 4),
+ 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_FLAT,
+};
+
+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 = i2c_smbus_read_i2c_block_data(data->client, ATLAS_REG_PH_DATA,
+ sizeof(data->buffer[0]), (u8 *) &data->buffer);
+
+ if (ret > 0)
+ 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");
projects / deliverable / linux.git / commitdiff
