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13#include <linux/module.h>
14#include <linux/i2c.h>
15#include <linux/iio/iio.h>
16#include <linux/iio/sysfs.h>
17#include <linux/iio/trigger_consumer.h>
18#include <linux/iio/buffer.h>
19#include <linux/iio/triggered_buffer.h>
20#include <linux/delay.h>
21
22#define MPL3115_STATUS 0x00
23#define MPL3115_OUT_PRESS 0x01
24#define MPL3115_OUT_TEMP 0x04
25#define MPL3115_WHO_AM_I 0x0c
26#define MPL3115_CTRL_REG1 0x26
27
28#define MPL3115_DEVICE_ID 0xc4
29
30#define MPL3115_STATUS_PRESS_RDY BIT(2)
31#define MPL3115_STATUS_TEMP_RDY BIT(1)
32
33#define MPL3115_CTRL_RESET BIT(2)
34#define MPL3115_CTRL_OST BIT(1)
35#define MPL3115_CTRL_ACTIVE BIT(0)
36#define MPL3115_CTRL_OS_258MS (BIT(5) | BIT(4))
37
38struct mpl3115_data {
39 struct i2c_client *client;
40 struct mutex lock;
41 u8 ctrl_reg1;
42};
43
44static int mpl3115_request(struct mpl3115_data *data)
45{
46 int ret, tries = 15;
47
48
49 ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
50 data->ctrl_reg1 | MPL3115_CTRL_OST);
51 if (ret < 0)
52 return ret;
53
54 while (tries-- > 0) {
55 ret = i2c_smbus_read_byte_data(data->client, MPL3115_CTRL_REG1);
56 if (ret < 0)
57 return ret;
58
59 if (!(ret & MPL3115_CTRL_OST))
60 break;
61 msleep(20);
62 }
63
64 if (tries < 0) {
65 dev_err(&data->client->dev, "data not ready\n");
66 return -EIO;
67 }
68
69 return 0;
70}
71
72static int mpl3115_read_raw(struct iio_dev *indio_dev,
73 struct iio_chan_spec const *chan,
74 int *val, int *val2, long mask)
75{
76 struct mpl3115_data *data = iio_priv(indio_dev);
77 __be32 tmp = 0;
78 int ret;
79
80 switch (mask) {
81 case IIO_CHAN_INFO_RAW:
82 ret = iio_device_claim_direct_mode(indio_dev);
83 if (ret)
84 return ret;
85
86 switch (chan->type) {
87 case IIO_PRESSURE:
88 mutex_lock(&data->lock);
89 ret = mpl3115_request(data);
90 if (ret < 0) {
91 mutex_unlock(&data->lock);
92 break;
93 }
94 ret = i2c_smbus_read_i2c_block_data(data->client,
95 MPL3115_OUT_PRESS, 3, (u8 *) &tmp);
96 mutex_unlock(&data->lock);
97 if (ret < 0)
98 break;
99 *val = be32_to_cpu(tmp) >> 12;
100 ret = IIO_VAL_INT;
101 break;
102 case IIO_TEMP:
103 mutex_lock(&data->lock);
104 ret = mpl3115_request(data);
105 if (ret < 0) {
106 mutex_unlock(&data->lock);
107 break;
108 }
109 ret = i2c_smbus_read_i2c_block_data(data->client,
110 MPL3115_OUT_TEMP, 2, (u8 *) &tmp);
111 mutex_unlock(&data->lock);
112 if (ret < 0)
113 break;
114 *val = sign_extend32(be32_to_cpu(tmp) >> 20, 11);
115 ret = IIO_VAL_INT;
116 break;
117 default:
118 ret = -EINVAL;
119 break;
120 }
121
122 iio_device_release_direct_mode(indio_dev);
123 return ret;
124
125 case IIO_CHAN_INFO_SCALE:
126 switch (chan->type) {
127 case IIO_PRESSURE:
128 *val = 0;
129 *val2 = 250;
130 return IIO_VAL_INT_PLUS_MICRO;
131 case IIO_TEMP:
132 *val = 0;
133 *val2 = 62500;
134 return IIO_VAL_INT_PLUS_MICRO;
135 default:
136 return -EINVAL;
137 }
138 }
139 return -EINVAL;
140}
141
142static irqreturn_t mpl3115_trigger_handler(int irq, void *p)
143{
144 struct iio_poll_func *pf = p;
145 struct iio_dev *indio_dev = pf->indio_dev;
146 struct mpl3115_data *data = iio_priv(indio_dev);
147
148
149
150
151
152
153
154 u8 buffer[16] __aligned(8);
155 int ret, pos = 0;
156
157 mutex_lock(&data->lock);
158 ret = mpl3115_request(data);
159 if (ret < 0) {
160 mutex_unlock(&data->lock);
161 goto done;
162 }
163
164 memset(buffer, 0, sizeof(buffer));
165 if (test_bit(0, indio_dev->active_scan_mask)) {
166 ret = i2c_smbus_read_i2c_block_data(data->client,
167 MPL3115_OUT_PRESS, 3, &buffer[pos]);
168 if (ret < 0) {
169 mutex_unlock(&data->lock);
170 goto done;
171 }
172 pos += 4;
173 }
174
175 if (test_bit(1, indio_dev->active_scan_mask)) {
176 ret = i2c_smbus_read_i2c_block_data(data->client,
177 MPL3115_OUT_TEMP, 2, &buffer[pos]);
178 if (ret < 0) {
179 mutex_unlock(&data->lock);
180 goto done;
181 }
182 }
183 mutex_unlock(&data->lock);
184
185 iio_push_to_buffers_with_timestamp(indio_dev, buffer,
186 iio_get_time_ns(indio_dev));
187
188done:
189 iio_trigger_notify_done(indio_dev->trig);
190 return IRQ_HANDLED;
191}
192
193static const struct iio_chan_spec mpl3115_channels[] = {
194 {
195 .type = IIO_PRESSURE,
196 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
197 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
198 .scan_index = 0,
199 .scan_type = {
200 .sign = 'u',
201 .realbits = 20,
202 .storagebits = 32,
203 .shift = 12,
204 .endianness = IIO_BE,
205 }
206 },
207 {
208 .type = IIO_TEMP,
209 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
210 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
211 .scan_index = 1,
212 .scan_type = {
213 .sign = 's',
214 .realbits = 12,
215 .storagebits = 16,
216 .shift = 4,
217 .endianness = IIO_BE,
218 }
219 },
220 IIO_CHAN_SOFT_TIMESTAMP(2),
221};
222
223static const struct iio_info mpl3115_info = {
224 .read_raw = &mpl3115_read_raw,
225};
226
227static int mpl3115_probe(struct i2c_client *client,
228 const struct i2c_device_id *id)
229{
230 struct mpl3115_data *data;
231 struct iio_dev *indio_dev;
232 int ret;
233
234 ret = i2c_smbus_read_byte_data(client, MPL3115_WHO_AM_I);
235 if (ret < 0)
236 return ret;
237 if (ret != MPL3115_DEVICE_ID)
238 return -ENODEV;
239
240 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
241 if (!indio_dev)
242 return -ENOMEM;
243
244 data = iio_priv(indio_dev);
245 data->client = client;
246 mutex_init(&data->lock);
247
248 i2c_set_clientdata(client, indio_dev);
249 indio_dev->info = &mpl3115_info;
250 indio_dev->name = id->name;
251 indio_dev->modes = INDIO_DIRECT_MODE;
252 indio_dev->channels = mpl3115_channels;
253 indio_dev->num_channels = ARRAY_SIZE(mpl3115_channels);
254
255
256 i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
257 MPL3115_CTRL_RESET);
258 msleep(50);
259
260 data->ctrl_reg1 = MPL3115_CTRL_OS_258MS;
261 ret = i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
262 data->ctrl_reg1);
263 if (ret < 0)
264 return ret;
265
266 ret = iio_triggered_buffer_setup(indio_dev, NULL,
267 mpl3115_trigger_handler, NULL);
268 if (ret < 0)
269 return ret;
270
271 ret = iio_device_register(indio_dev);
272 if (ret < 0)
273 goto buffer_cleanup;
274 return 0;
275
276buffer_cleanup:
277 iio_triggered_buffer_cleanup(indio_dev);
278 return ret;
279}
280
281static int mpl3115_standby(struct mpl3115_data *data)
282{
283 return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
284 data->ctrl_reg1 & ~MPL3115_CTRL_ACTIVE);
285}
286
287static int mpl3115_remove(struct i2c_client *client)
288{
289 struct iio_dev *indio_dev = i2c_get_clientdata(client);
290
291 iio_device_unregister(indio_dev);
292 iio_triggered_buffer_cleanup(indio_dev);
293 mpl3115_standby(iio_priv(indio_dev));
294
295 return 0;
296}
297
298#ifdef CONFIG_PM_SLEEP
299static int mpl3115_suspend(struct device *dev)
300{
301 return mpl3115_standby(iio_priv(i2c_get_clientdata(
302 to_i2c_client(dev))));
303}
304
305static int mpl3115_resume(struct device *dev)
306{
307 struct mpl3115_data *data = iio_priv(i2c_get_clientdata(
308 to_i2c_client(dev)));
309
310 return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
311 data->ctrl_reg1);
312}
313
314static SIMPLE_DEV_PM_OPS(mpl3115_pm_ops, mpl3115_suspend, mpl3115_resume);
315#define MPL3115_PM_OPS (&mpl3115_pm_ops)
316#else
317#define MPL3115_PM_OPS NULL
318#endif
319
320static const struct i2c_device_id mpl3115_id[] = {
321 { "mpl3115", 0 },
322 { }
323};
324MODULE_DEVICE_TABLE(i2c, mpl3115_id);
325
326static const struct of_device_id mpl3115_of_match[] = {
327 { .compatible = "fsl,mpl3115" },
328 { }
329};
330MODULE_DEVICE_TABLE(of, mpl3115_of_match);
331
332static struct i2c_driver mpl3115_driver = {
333 .driver = {
334 .name = "mpl3115",
335 .of_match_table = mpl3115_of_match,
336 .pm = MPL3115_PM_OPS,
337 },
338 .probe = mpl3115_probe,
339 .remove = mpl3115_remove,
340 .id_table = mpl3115_id,
341};
342module_i2c_driver(mpl3115_driver);
343
344MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
345MODULE_DESCRIPTION("Freescale MPL3115 pressure/temperature driver");
346MODULE_LICENSE("GPL");
347
