summaryrefslogtreecommitdiff
path: root/drivers/iio/chemical/atlas-ph-sensor.c
blob: 62b37cd8fb56d840c66b819df65a48ea56461c61 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
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 *) &reg, 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, &reg);

			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,
				 &reg, 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");