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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 u8 buffer[16];
148 int ret, pos = 0;
149
150 mutex_lock(&data->lock);
151 ret = mpl3115_request(data);
152 if (ret < 0) {
153 mutex_unlock(&data->lock);
154 goto done;
155 }
156
157 memset(buffer, 0, sizeof(buffer));
158 if (test_bit(0, indio_dev->active_scan_mask)) {
159 ret = i2c_smbus_read_i2c_block_data(data->client,
160 MPL3115_OUT_PRESS, 3, &buffer[pos]);
161 if (ret < 0) {
162 mutex_unlock(&data->lock);
163 goto done;
164 }
165 pos += 4;
166 }
167
168 if (test_bit(1, indio_dev->active_scan_mask)) {
169 ret = i2c_smbus_read_i2c_block_data(data->client,
170 MPL3115_OUT_TEMP, 2, &buffer[pos]);
171 if (ret < 0) {
172 mutex_unlock(&data->lock);
173 goto done;
174 }
175 }
176 mutex_unlock(&data->lock);
177
178 iio_push_to_buffers_with_timestamp(indio_dev, buffer,
179 iio_get_time_ns(indio_dev));
180
181done:
182 iio_trigger_notify_done(indio_dev->trig);
183 return IRQ_HANDLED;
184}
185
186static const struct iio_chan_spec mpl3115_channels[] = {
187 {
188 .type = IIO_PRESSURE,
189 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
190 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
191 .scan_index = 0,
192 .scan_type = {
193 .sign = 'u',
194 .realbits = 20,
195 .storagebits = 32,
196 .shift = 12,
197 .endianness = IIO_BE,
198 }
199 },
200 {
201 .type = IIO_TEMP,
202 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
203 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
204 .scan_index = 1,
205 .scan_type = {
206 .sign = 's',
207 .realbits = 12,
208 .storagebits = 16,
209 .shift = 4,
210 .endianness = IIO_BE,
211 }
212 },
213 IIO_CHAN_SOFT_TIMESTAMP(2),
214};
215
216static const struct iio_info mpl3115_info = {
217 .read_raw = &mpl3115_read_raw,
218};
219
220static int mpl3115_probe(struct i2c_client *client,
221 const struct i2c_device_id *id)
222{
223 struct mpl3115_data *data;
224 struct iio_dev *indio_dev;
225 int ret;
226
227 ret = i2c_smbus_read_byte_data(client, MPL3115_WHO_AM_I);
228 if (ret < 0)
229 return ret;
230 if (ret != MPL3115_DEVICE_ID)
231 return -ENODEV;
232
233 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
234 if (!indio_dev)
235 return -ENOMEM;
236
237 data = iio_priv(indio_dev);
238 data->client = client;
239 mutex_init(&data->lock);
240
241 i2c_set_clientdata(client, indio_dev);
242 indio_dev->info = &mpl3115_info;
243 indio_dev->name = id->name;
244 indio_dev->dev.parent = &client->dev;
245 indio_dev->modes = INDIO_DIRECT_MODE;
246 indio_dev->channels = mpl3115_channels;
247 indio_dev->num_channels = ARRAY_SIZE(mpl3115_channels);
248
249
250 i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
251 MPL3115_CTRL_RESET);
252 msleep(50);
253
254 data->ctrl_reg1 = MPL3115_CTRL_OS_258MS;
255 ret = i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
256 data->ctrl_reg1);
257 if (ret < 0)
258 return ret;
259
260 ret = iio_triggered_buffer_setup(indio_dev, NULL,
261 mpl3115_trigger_handler, NULL);
262 if (ret < 0)
263 return ret;
264
265 ret = iio_device_register(indio_dev);
266 if (ret < 0)
267 goto buffer_cleanup;
268 return 0;
269
270buffer_cleanup:
271 iio_triggered_buffer_cleanup(indio_dev);
272 return ret;
273}
274
275static int mpl3115_standby(struct mpl3115_data *data)
276{
277 return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
278 data->ctrl_reg1 & ~MPL3115_CTRL_ACTIVE);
279}
280
281static int mpl3115_remove(struct i2c_client *client)
282{
283 struct iio_dev *indio_dev = i2c_get_clientdata(client);
284
285 iio_device_unregister(indio_dev);
286 iio_triggered_buffer_cleanup(indio_dev);
287 mpl3115_standby(iio_priv(indio_dev));
288
289 return 0;
290}
291
292#ifdef CONFIG_PM_SLEEP
293static int mpl3115_suspend(struct device *dev)
294{
295 return mpl3115_standby(iio_priv(i2c_get_clientdata(
296 to_i2c_client(dev))));
297}
298
299static int mpl3115_resume(struct device *dev)
300{
301 struct mpl3115_data *data = iio_priv(i2c_get_clientdata(
302 to_i2c_client(dev)));
303
304 return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
305 data->ctrl_reg1);
306}
307
308static SIMPLE_DEV_PM_OPS(mpl3115_pm_ops, mpl3115_suspend, mpl3115_resume);
309#define MPL3115_PM_OPS (&mpl3115_pm_ops)
310#else
311#define MPL3115_PM_OPS NULL
312#endif
313
314static const struct i2c_device_id mpl3115_id[] = {
315 { "mpl3115", 0 },
316 { }
317};
318MODULE_DEVICE_TABLE(i2c, mpl3115_id);
319
320static const struct of_device_id mpl3115_of_match[] = {
321 { .compatible = "fsl,mpl3115" },
322 { }
323};
324MODULE_DEVICE_TABLE(of, mpl3115_of_match);
325
326static struct i2c_driver mpl3115_driver = {
327 .driver = {
328 .name = "mpl3115",
329 .of_match_table = mpl3115_of_match,
330 .pm = MPL3115_PM_OPS,
331 },
332 .probe = mpl3115_probe,
333 .remove = mpl3115_remove,
334 .id_table = mpl3115_id,
335};
336module_i2c_driver(mpl3115_driver);
337
338MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
339MODULE_DESCRIPTION("Freescale MPL3115 pressure/temperature driver");
340MODULE_LICENSE("GPL");
341
