1 /*
2  * ADIS16203 Programmable Digital Vibration Sensor driver
3  *
4  * Copyright 2010 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/delay.h>
10 #include <linux/mutex.h>
11 #include <linux/device.h>
12 #include <linux/kernel.h>
13 #include <linux/spi/spi.h>
14 #include <linux/slab.h>
15 #include <linux/sysfs.h>
16 #include <linux/module.h>
17 
18 #include "../iio.h"
19 #include "../sysfs.h"
20 #include "../buffer.h"
21 
22 #include "adis16203.h"
23 
24 #define DRIVER_NAME		"adis16203"
25 
26 /**
27  * adis16203_spi_write_reg_8() - write single byte to a register
28  * @indio_dev: iio device associated with child of actual device
29  * @reg_address: the address of the register to be written
30  * @val: the value to write
31  **/
adis16203_spi_write_reg_8(struct iio_dev * indio_dev,u8 reg_address,u8 val)32 static int adis16203_spi_write_reg_8(struct iio_dev *indio_dev,
33 				     u8 reg_address,
34 				     u8 val)
35 {
36 	int ret;
37 	struct adis16203_state *st = iio_priv(indio_dev);
38 
39 	mutex_lock(&st->buf_lock);
40 	st->tx[0] = ADIS16203_WRITE_REG(reg_address);
41 	st->tx[1] = val;
42 
43 	ret = spi_write(st->us, st->tx, 2);
44 	mutex_unlock(&st->buf_lock);
45 
46 	return ret;
47 }
48 
49 /**
50  * adis16203_spi_write_reg_16() - write 2 bytes to a pair of registers
51  * @indio_dev: iio device associated with child of actual device
52  * @reg_address: the address of the lower of the two registers. Second register
53  *               is assumed to have address one greater.
54  * @val: value to be written
55  **/
adis16203_spi_write_reg_16(struct iio_dev * indio_dev,u8 lower_reg_address,u16 value)56 static int adis16203_spi_write_reg_16(struct iio_dev *indio_dev,
57 				      u8 lower_reg_address,
58 				      u16 value)
59 {
60 	int ret;
61 	struct spi_message msg;
62 	struct adis16203_state *st = iio_priv(indio_dev);
63 	struct spi_transfer xfers[] = {
64 		{
65 			.tx_buf = st->tx,
66 			.bits_per_word = 8,
67 			.len = 2,
68 			.cs_change = 1,
69 		}, {
70 			.tx_buf = st->tx + 2,
71 			.bits_per_word = 8,
72 			.len = 2,
73 		},
74 	};
75 
76 	mutex_lock(&st->buf_lock);
77 	st->tx[0] = ADIS16203_WRITE_REG(lower_reg_address);
78 	st->tx[1] = value & 0xFF;
79 	st->tx[2] = ADIS16203_WRITE_REG(lower_reg_address + 1);
80 	st->tx[3] = (value >> 8) & 0xFF;
81 
82 	spi_message_init(&msg);
83 	spi_message_add_tail(&xfers[0], &msg);
84 	spi_message_add_tail(&xfers[1], &msg);
85 	ret = spi_sync(st->us, &msg);
86 	mutex_unlock(&st->buf_lock);
87 
88 	return ret;
89 }
90 
91 /**
92  * adis16203_spi_read_reg_16() - read 2 bytes from a 16-bit register
93  * @indio_dev: iio device associated with child of actual device
94  * @reg_address: the address of the lower of the two registers. Second register
95  *               is assumed to have address one greater.
96  * @val: somewhere to pass back the value read
97  **/
adis16203_spi_read_reg_16(struct iio_dev * indio_dev,u8 lower_reg_address,u16 * val)98 static int adis16203_spi_read_reg_16(struct iio_dev *indio_dev,
99 		u8 lower_reg_address,
100 		u16 *val)
101 {
102 	struct spi_message msg;
103 	struct adis16203_state *st = iio_priv(indio_dev);
104 	int ret;
105 	struct spi_transfer xfers[] = {
106 		{
107 			.tx_buf = st->tx,
108 			.bits_per_word = 8,
109 			.len = 2,
110 			.cs_change = 1,
111 			.delay_usecs = 20,
112 		}, {
113 			.rx_buf = st->rx,
114 			.bits_per_word = 8,
115 			.len = 2,
116 			.delay_usecs = 20,
117 		},
118 	};
119 
120 	mutex_lock(&st->buf_lock);
121 	st->tx[0] = ADIS16203_READ_REG(lower_reg_address);
122 	st->tx[1] = 0;
123 
124 	spi_message_init(&msg);
125 	spi_message_add_tail(&xfers[0], &msg);
126 	spi_message_add_tail(&xfers[1], &msg);
127 	ret = spi_sync(st->us, &msg);
128 	if (ret) {
129 		dev_err(&st->us->dev, "problem when reading 16 bit register 0x%02X",
130 				lower_reg_address);
131 		goto error_ret;
132 	}
133 	*val = (st->rx[0] << 8) | st->rx[1];
134 
135 error_ret:
136 	mutex_unlock(&st->buf_lock);
137 	return ret;
138 }
139 
adis16203_check_status(struct iio_dev * indio_dev)140 static int adis16203_check_status(struct iio_dev *indio_dev)
141 {
142 	u16 status;
143 	int ret;
144 
145 	ret = adis16203_spi_read_reg_16(indio_dev,
146 					ADIS16203_DIAG_STAT,
147 					&status);
148 	if (ret < 0) {
149 		dev_err(&indio_dev->dev, "Reading status failed\n");
150 		goto error_ret;
151 	}
152 	ret = status & 0x1F;
153 
154 	if (status & ADIS16203_DIAG_STAT_SELFTEST_FAIL)
155 		dev_err(&indio_dev->dev, "Self test failure\n");
156 	if (status & ADIS16203_DIAG_STAT_SPI_FAIL)
157 		dev_err(&indio_dev->dev, "SPI failure\n");
158 	if (status & ADIS16203_DIAG_STAT_FLASH_UPT)
159 		dev_err(&indio_dev->dev, "Flash update failed\n");
160 	if (status & ADIS16203_DIAG_STAT_POWER_HIGH)
161 		dev_err(&indio_dev->dev, "Power supply above 3.625V\n");
162 	if (status & ADIS16203_DIAG_STAT_POWER_LOW)
163 		dev_err(&indio_dev->dev, "Power supply below 3.15V\n");
164 
165 error_ret:
166 	return ret;
167 }
168 
adis16203_reset(struct iio_dev * indio_dev)169 static int adis16203_reset(struct iio_dev *indio_dev)
170 {
171 	int ret;
172 	ret = adis16203_spi_write_reg_8(indio_dev,
173 			ADIS16203_GLOB_CMD,
174 			ADIS16203_GLOB_CMD_SW_RESET);
175 	if (ret)
176 		dev_err(&indio_dev->dev, "problem resetting device");
177 
178 	return ret;
179 }
180 
adis16203_write_reset(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)181 static ssize_t adis16203_write_reset(struct device *dev,
182 		struct device_attribute *attr,
183 		const char *buf, size_t len)
184 {
185 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
186 	if (len < 1)
187 		return -EINVAL;
188 	switch (buf[0]) {
189 	case '1':
190 	case 'y':
191 	case 'Y':
192 		return adis16203_reset(indio_dev);
193 	}
194 	return -EINVAL;
195 }
196 
adis16203_set_irq(struct iio_dev * indio_dev,bool enable)197 int adis16203_set_irq(struct iio_dev *indio_dev, bool enable)
198 {
199 	int ret = 0;
200 	u16 msc;
201 
202 	ret = adis16203_spi_read_reg_16(indio_dev, ADIS16203_MSC_CTRL, &msc);
203 	if (ret)
204 		goto error_ret;
205 
206 	msc |= ADIS16203_MSC_CTRL_ACTIVE_HIGH;
207 	msc &= ~ADIS16203_MSC_CTRL_DATA_RDY_DIO1;
208 	if (enable)
209 		msc |= ADIS16203_MSC_CTRL_DATA_RDY_EN;
210 	else
211 		msc &= ~ADIS16203_MSC_CTRL_DATA_RDY_EN;
212 
213 	ret = adis16203_spi_write_reg_16(indio_dev, ADIS16203_MSC_CTRL, msc);
214 
215 error_ret:
216 	return ret;
217 }
218 
adis16203_self_test(struct iio_dev * indio_dev)219 static int adis16203_self_test(struct iio_dev *indio_dev)
220 {
221 	int ret;
222 	ret = adis16203_spi_write_reg_16(indio_dev,
223 			ADIS16203_MSC_CTRL,
224 			ADIS16203_MSC_CTRL_SELF_TEST_EN);
225 	if (ret) {
226 		dev_err(&indio_dev->dev, "problem starting self test");
227 		goto err_ret;
228 	}
229 
230 	adis16203_check_status(indio_dev);
231 
232 err_ret:
233 	return ret;
234 }
235 
adis16203_initial_setup(struct iio_dev * indio_dev)236 static int adis16203_initial_setup(struct iio_dev *indio_dev)
237 {
238 	int ret;
239 
240 	/* Disable IRQ */
241 	ret = adis16203_set_irq(indio_dev, false);
242 	if (ret) {
243 		dev_err(&indio_dev->dev, "disable irq failed");
244 		goto err_ret;
245 	}
246 
247 	/* Do self test */
248 	ret = adis16203_self_test(indio_dev);
249 	if (ret) {
250 		dev_err(&indio_dev->dev, "self test failure");
251 		goto err_ret;
252 	}
253 
254 	/* Read status register to check the result */
255 	ret = adis16203_check_status(indio_dev);
256 	if (ret) {
257 		adis16203_reset(indio_dev);
258 		dev_err(&indio_dev->dev, "device not playing ball -> reset");
259 		msleep(ADIS16203_STARTUP_DELAY);
260 		ret = adis16203_check_status(indio_dev);
261 		if (ret) {
262 			dev_err(&indio_dev->dev, "giving up");
263 			goto err_ret;
264 		}
265 	}
266 
267 err_ret:
268 	return ret;
269 }
270 
271 enum adis16203_chan {
272 	in_supply,
273 	in_aux,
274 	incli_x,
275 	incli_y,
276 	temp,
277 };
278 
279 static u8 adis16203_addresses[5][2] = {
280 	[in_supply] = { ADIS16203_SUPPLY_OUT },
281 	[in_aux] = { ADIS16203_AUX_ADC },
282 	[incli_x] = { ADIS16203_XINCL_OUT, ADIS16203_INCL_NULL},
283 	[incli_y] = { ADIS16203_YINCL_OUT },
284 	[temp] = { ADIS16203_TEMP_OUT }
285 };
286 
adis16203_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)287 static int adis16203_write_raw(struct iio_dev *indio_dev,
288 			       struct iio_chan_spec const *chan,
289 			       int val,
290 			       int val2,
291 			       long mask)
292 {
293 	/* currently only one writable parameter which keeps this simple */
294 	u8 addr = adis16203_addresses[chan->address][1];
295 	return adis16203_spi_write_reg_16(indio_dev, addr, val & 0x3FFF);
296 }
297 
adis16203_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)298 static int adis16203_read_raw(struct iio_dev *indio_dev,
299 			      struct iio_chan_spec const *chan,
300 			      int *val, int *val2,
301 			      long mask)
302 {
303 	int ret;
304 	int bits;
305 	u8 addr;
306 	s16 val16;
307 	switch (mask) {
308 	case 0:
309 		mutex_lock(&indio_dev->mlock);
310 		addr = adis16203_addresses[chan->address][0];
311 		ret = adis16203_spi_read_reg_16(indio_dev, addr, &val16);
312 		if (ret) {
313 			mutex_unlock(&indio_dev->mlock);
314 			return ret;
315 		}
316 
317 		if (val16 & ADIS16203_ERROR_ACTIVE) {
318 			ret = adis16203_check_status(indio_dev);
319 			if (ret) {
320 				mutex_unlock(&indio_dev->mlock);
321 				return ret;
322 			}
323 		}
324 		val16 = val16 & ((1 << chan->scan_type.realbits) - 1);
325 		if (chan->scan_type.sign == 's')
326 			val16 = (s16)(val16 <<
327 				      (16 - chan->scan_type.realbits)) >>
328 				(16 - chan->scan_type.realbits);
329 		*val = val16;
330 		mutex_unlock(&indio_dev->mlock);
331 		return IIO_VAL_INT;
332 	case IIO_CHAN_INFO_SCALE:
333 		switch (chan->type) {
334 		case IIO_VOLTAGE:
335 			*val = 0;
336 			if (chan->channel == 0)
337 				*val2 = 1220;
338 			else
339 				*val2 = 610;
340 			return IIO_VAL_INT_PLUS_MICRO;
341 		case IIO_TEMP:
342 			*val = 0;
343 			*val2 = -470000;
344 			return IIO_VAL_INT_PLUS_MICRO;
345 		case IIO_INCLI:
346 			*val = 0;
347 			*val2 = 25000;
348 			return IIO_VAL_INT_PLUS_MICRO;
349 		default:
350 			return -EINVAL;
351 		}
352 	case IIO_CHAN_INFO_OFFSET:
353 		*val = 25;
354 		return IIO_VAL_INT;
355 	case IIO_CHAN_INFO_CALIBBIAS:
356 		bits = 14;
357 		mutex_lock(&indio_dev->mlock);
358 		addr = adis16203_addresses[chan->address][1];
359 		ret = adis16203_spi_read_reg_16(indio_dev, addr, &val16);
360 		if (ret) {
361 			mutex_unlock(&indio_dev->mlock);
362 			return ret;
363 		}
364 		val16 &= (1 << bits) - 1;
365 		val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
366 		*val = val16;
367 		mutex_unlock(&indio_dev->mlock);
368 		return IIO_VAL_INT;
369 	default:
370 		return -EINVAL;
371 	}
372 }
373 
374 static struct iio_chan_spec adis16203_channels[] = {
375 	IIO_CHAN(IIO_VOLTAGE, 0, 1, 0, "supply", 0, 0,
376 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
377 		 in_supply, ADIS16203_SCAN_SUPPLY,
378 		 IIO_ST('u', 12, 16, 0), 0),
379 	IIO_CHAN(IIO_VOLTAGE, 0, 1, 0, NULL, 1, 0,
380 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
381 		 in_aux, ADIS16203_SCAN_AUX_ADC,
382 		 IIO_ST('u', 12, 16, 0), 0),
383 	IIO_CHAN(IIO_INCLI, 1, 0, 0, NULL, 0, IIO_MOD_X,
384 		 IIO_CHAN_INFO_SCALE_SHARED_BIT |
385 		 IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT,
386 		 incli_x, ADIS16203_SCAN_INCLI_X,
387 		 IIO_ST('s', 14, 16, 0), 0),
388 	/* Fixme: Not what it appears to be - see data sheet */
389 	IIO_CHAN(IIO_INCLI, 1, 0, 0, NULL, 0, IIO_MOD_Y,
390 		 IIO_CHAN_INFO_SCALE_SHARED_BIT,
391 		 incli_y, ADIS16203_SCAN_INCLI_Y,
392 		 IIO_ST('s', 14, 16, 0), 0),
393 	IIO_CHAN(IIO_TEMP, 0, 1, 0, NULL, 0, 0,
394 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT |
395 		 IIO_CHAN_INFO_OFFSET_SEPARATE_BIT,
396 		 temp, ADIS16203_SCAN_TEMP,
397 		 IIO_ST('u', 12, 16, 0), 0),
398 	IIO_CHAN_SOFT_TIMESTAMP(5),
399 };
400 
401 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16203_write_reset, 0);
402 
403 static struct attribute *adis16203_attributes[] = {
404 	&iio_dev_attr_reset.dev_attr.attr,
405 	NULL
406 };
407 
408 static const struct attribute_group adis16203_attribute_group = {
409 	.attrs = adis16203_attributes,
410 };
411 
412 static const struct iio_info adis16203_info = {
413 	.attrs = &adis16203_attribute_group,
414 	.read_raw = &adis16203_read_raw,
415 	.write_raw = &adis16203_write_raw,
416 	.driver_module = THIS_MODULE,
417 };
418 
adis16203_probe(struct spi_device * spi)419 static int __devinit adis16203_probe(struct spi_device *spi)
420 {
421 	int ret;
422 	struct iio_dev *indio_dev;
423 	struct adis16203_state *st;
424 
425 	/* setup the industrialio driver allocated elements */
426 	indio_dev = iio_allocate_device(sizeof(*st));
427 	if (indio_dev == NULL) {
428 		ret = -ENOMEM;
429 		goto error_ret;
430 	}
431 	st = iio_priv(indio_dev);
432 	/* this is only used for removal purposes */
433 	spi_set_drvdata(spi, indio_dev);
434 	st->us = spi;
435 	mutex_init(&st->buf_lock);
436 
437 	indio_dev->name = spi->dev.driver->name;
438 	indio_dev->dev.parent = &spi->dev;
439 	indio_dev->channels = adis16203_channels;
440 	indio_dev->num_channels = ARRAY_SIZE(adis16203_channels);
441 	indio_dev->info = &adis16203_info;
442 	indio_dev->modes = INDIO_DIRECT_MODE;
443 
444 	ret = adis16203_configure_ring(indio_dev);
445 	if (ret)
446 		goto error_free_dev;
447 
448 	ret = iio_buffer_register(indio_dev,
449 				  adis16203_channels,
450 				  ARRAY_SIZE(adis16203_channels));
451 	if (ret) {
452 		printk(KERN_ERR "failed to initialize the ring\n");
453 		goto error_unreg_ring_funcs;
454 	}
455 
456 	if (spi->irq) {
457 		ret = adis16203_probe_trigger(indio_dev);
458 		if (ret)
459 			goto error_uninitialize_ring;
460 	}
461 
462 	/* Get the device into a sane initial state */
463 	ret = adis16203_initial_setup(indio_dev);
464 	if (ret)
465 		goto error_remove_trigger;
466 
467 	ret = iio_device_register(indio_dev);
468 	if (ret)
469 		goto error_remove_trigger;
470 
471 	return 0;
472 
473 error_remove_trigger:
474 	adis16203_remove_trigger(indio_dev);
475 error_uninitialize_ring:
476 	iio_buffer_unregister(indio_dev);
477 error_unreg_ring_funcs:
478 	adis16203_unconfigure_ring(indio_dev);
479 error_free_dev:
480 	iio_free_device(indio_dev);
481 error_ret:
482 	return ret;
483 }
484 
adis16203_remove(struct spi_device * spi)485 static int adis16203_remove(struct spi_device *spi)
486 {
487 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
488 
489 	iio_device_unregister(indio_dev);
490 	adis16203_remove_trigger(indio_dev);
491 	iio_buffer_unregister(indio_dev);
492 	adis16203_unconfigure_ring(indio_dev);
493 	iio_free_device(indio_dev);
494 
495 	return 0;
496 }
497 
498 static struct spi_driver adis16203_driver = {
499 	.driver = {
500 		.name = "adis16203",
501 		.owner = THIS_MODULE,
502 	},
503 	.probe = adis16203_probe,
504 	.remove = __devexit_p(adis16203_remove),
505 };
506 module_spi_driver(adis16203_driver);
507 
508 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
509 MODULE_DESCRIPTION("Analog Devices ADIS16203 Programmable Digital Vibration Sensor driver");
510 MODULE_LICENSE("GPL v2");
511 MODULE_ALIAS("spi:adis16203");
512