2 * mpl3115.c - Support for Freescale MPL3115A2 pressure/temperature sensor
4 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
6 * This file is subject to the terms and conditions of version 2 of
7 * the GNU General Public License. See the file COPYING in the main
8 * directory of this archive for more details.
10 * (7-bit I2C slave address 0x60)
12 * TODO: FIFO buffer, altimeter mode, oversampling, continuous mode,
13 * interrupts, user offset correction, raw mode
16 #include <linux/module.h>
17 #include <linux/i2c.h>
18 #include <linux/iio/iio.h>
19 #include <linux/iio/sysfs.h>
20 #include <linux/iio/trigger_consumer.h>
21 #include <linux/iio/buffer.h>
22 #include <linux/iio/triggered_buffer.h>
23 #include <linux/delay.h>
25 #define MPL3115_STATUS 0x00
26 #define MPL3115_OUT_PRESS 0x01 /* MSB first, 20 bit */
27 #define MPL3115_OUT_TEMP 0x04 /* MSB first, 12 bit */
28 #define MPL3115_WHO_AM_I 0x0c
29 #define MPL3115_CTRL_REG1 0x26
31 #define MPL3115_DEVICE_ID 0xc4
33 #define MPL3115_STATUS_PRESS_RDY BIT(2)
34 #define MPL3115_STATUS_TEMP_RDY BIT(1)
36 #define MPL3115_CTRL_RESET BIT(2) /* software reset */
37 #define MPL3115_CTRL_OST BIT(1) /* initiate measurement */
38 #define MPL3115_CTRL_ACTIVE BIT(0) /* continuous measurement */
39 #define MPL3115_CTRL_OS_258MS (BIT(5) | BIT(4)) /* 64x oversampling */
42 struct i2c_client *client;
47 static int mpl3115_request(struct mpl3115_data *data)
51 /* trigger measurement */
52 ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
53 data->ctrl_reg1 | MPL3115_CTRL_OST);
58 ret = i2c_smbus_read_byte_data(data->client, MPL3115_CTRL_REG1);
61 /* wait for data ready, i.e. OST cleared */
62 if (!(ret & MPL3115_CTRL_OST))
68 dev_err(&data->client->dev, "data not ready\n");
75 static int mpl3115_read_raw(struct iio_dev *indio_dev,
76 struct iio_chan_spec const *chan,
77 int *val, int *val2, long mask)
79 struct mpl3115_data *data = iio_priv(indio_dev);
84 case IIO_CHAN_INFO_RAW:
85 ret = iio_device_claim_direct_mode(indio_dev);
90 case IIO_PRESSURE: /* in 0.25 pascal / LSB */
91 mutex_lock(&data->lock);
92 ret = mpl3115_request(data);
94 mutex_unlock(&data->lock);
97 ret = i2c_smbus_read_i2c_block_data(data->client,
98 MPL3115_OUT_PRESS, 3, (u8 *) &tmp);
99 mutex_unlock(&data->lock);
102 *val = be32_to_cpu(tmp) >> 12;
105 case IIO_TEMP: /* in 0.0625 celsius / LSB */
106 mutex_lock(&data->lock);
107 ret = mpl3115_request(data);
109 mutex_unlock(&data->lock);
112 ret = i2c_smbus_read_i2c_block_data(data->client,
113 MPL3115_OUT_TEMP, 2, (u8 *) &tmp);
114 mutex_unlock(&data->lock);
117 *val = sign_extend32(be32_to_cpu(tmp) >> 20, 11);
125 iio_device_release_direct_mode(indio_dev);
128 case IIO_CHAN_INFO_SCALE:
129 switch (chan->type) {
132 *val2 = 250; /* want kilopascal */
133 return IIO_VAL_INT_PLUS_MICRO;
137 return IIO_VAL_INT_PLUS_MICRO;
145 static irqreturn_t mpl3115_trigger_handler(int irq, void *p)
147 struct iio_poll_func *pf = p;
148 struct iio_dev *indio_dev = pf->indio_dev;
149 struct mpl3115_data *data = iio_priv(indio_dev);
150 u8 buffer[16]; /* 32-bit channel + 16-bit channel + padding + ts */
153 mutex_lock(&data->lock);
154 ret = mpl3115_request(data);
156 mutex_unlock(&data->lock);
160 memset(buffer, 0, sizeof(buffer));
161 if (test_bit(0, indio_dev->active_scan_mask)) {
162 ret = i2c_smbus_read_i2c_block_data(data->client,
163 MPL3115_OUT_PRESS, 3, &buffer[pos]);
165 mutex_unlock(&data->lock);
171 if (test_bit(1, indio_dev->active_scan_mask)) {
172 ret = i2c_smbus_read_i2c_block_data(data->client,
173 MPL3115_OUT_TEMP, 2, &buffer[pos]);
175 mutex_unlock(&data->lock);
179 mutex_unlock(&data->lock);
181 iio_push_to_buffers_with_timestamp(indio_dev, buffer,
182 iio_get_time_ns(indio_dev));
185 iio_trigger_notify_done(indio_dev->trig);
189 static const struct iio_chan_spec mpl3115_channels[] = {
191 .type = IIO_PRESSURE,
192 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
193 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
200 .endianness = IIO_BE,
205 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
206 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
213 .endianness = IIO_BE,
216 IIO_CHAN_SOFT_TIMESTAMP(2),
219 static const struct iio_info mpl3115_info = {
220 .read_raw = &mpl3115_read_raw,
223 static int mpl3115_probe(struct i2c_client *client,
224 const struct i2c_device_id *id)
226 struct mpl3115_data *data;
227 struct iio_dev *indio_dev;
230 ret = i2c_smbus_read_byte_data(client, MPL3115_WHO_AM_I);
233 if (ret != MPL3115_DEVICE_ID)
236 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
240 data = iio_priv(indio_dev);
241 data->client = client;
242 mutex_init(&data->lock);
244 i2c_set_clientdata(client, indio_dev);
245 indio_dev->info = &mpl3115_info;
246 indio_dev->name = id->name;
247 indio_dev->dev.parent = &client->dev;
248 indio_dev->modes = INDIO_DIRECT_MODE;
249 indio_dev->channels = mpl3115_channels;
250 indio_dev->num_channels = ARRAY_SIZE(mpl3115_channels);
252 /* software reset, I2C transfer is aborted (fails) */
253 i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
257 data->ctrl_reg1 = MPL3115_CTRL_OS_258MS;
258 ret = i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
263 ret = iio_triggered_buffer_setup(indio_dev, NULL,
264 mpl3115_trigger_handler, NULL);
268 ret = iio_device_register(indio_dev);
274 iio_triggered_buffer_cleanup(indio_dev);
278 static int mpl3115_standby(struct mpl3115_data *data)
280 return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
281 data->ctrl_reg1 & ~MPL3115_CTRL_ACTIVE);
284 static int mpl3115_remove(struct i2c_client *client)
286 struct iio_dev *indio_dev = i2c_get_clientdata(client);
288 iio_device_unregister(indio_dev);
289 iio_triggered_buffer_cleanup(indio_dev);
290 mpl3115_standby(iio_priv(indio_dev));
295 #ifdef CONFIG_PM_SLEEP
296 static int mpl3115_suspend(struct device *dev)
298 return mpl3115_standby(iio_priv(i2c_get_clientdata(
299 to_i2c_client(dev))));
302 static int mpl3115_resume(struct device *dev)
304 struct mpl3115_data *data = iio_priv(i2c_get_clientdata(
305 to_i2c_client(dev)));
307 return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
311 static SIMPLE_DEV_PM_OPS(mpl3115_pm_ops, mpl3115_suspend, mpl3115_resume);
312 #define MPL3115_PM_OPS (&mpl3115_pm_ops)
314 #define MPL3115_PM_OPS NULL
317 static const struct i2c_device_id mpl3115_id[] = {
321 MODULE_DEVICE_TABLE(i2c, mpl3115_id);
323 static const struct of_device_id mpl3115_of_match[] = {
324 { .compatible = "fsl,mpl3115" },
327 MODULE_DEVICE_TABLE(of, mpl3115_of_match);
329 static struct i2c_driver mpl3115_driver = {
332 .of_match_table = mpl3115_of_match,
333 .pm = MPL3115_PM_OPS,
335 .probe = mpl3115_probe,
336 .remove = mpl3115_remove,
337 .id_table = mpl3115_id,
339 module_i2c_driver(mpl3115_driver);
341 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
342 MODULE_DESCRIPTION("Freescale MPL3115 pressure/temperature driver");
343 MODULE_LICENSE("GPL");