1 /*
2  * ADIS16204 Programmable High-g Digital Impact Sensor and Recorder
3  *
4  * Copyright 2010 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/delay.h>
12 #include <linux/mutex.h>
13 #include <linux/device.h>
14 #include <linux/kernel.h>
15 #include <linux/spi/spi.h>
16 #include <linux/slab.h>
17 #include <linux/sysfs.h>
18 #include <linux/list.h>
19 #include <linux/module.h>
20 
21 #include "../iio.h"
22 #include "../sysfs.h"
23 #include "../buffer.h"
24 
25 #include "adis16204.h"
26 
27 #define DRIVER_NAME		"adis16204"
28 
29 /**
30  * adis16204_spi_write_reg_8() - write single byte to a register
31  * @dev: device associated with child of actual device (iio_dev or iio_trig)
32  * @reg_address: the address of the register to be written
33  * @val: the value to write
34  **/
adis16204_spi_write_reg_8(struct iio_dev * indio_dev,u8 reg_address,u8 val)35 static int adis16204_spi_write_reg_8(struct iio_dev *indio_dev,
36 		u8 reg_address,
37 		u8 val)
38 {
39 	int ret;
40 	struct adis16204_state *st = iio_priv(indio_dev);
41 
42 	mutex_lock(&st->buf_lock);
43 	st->tx[0] = ADIS16204_WRITE_REG(reg_address);
44 	st->tx[1] = val;
45 
46 	ret = spi_write(st->us, st->tx, 2);
47 	mutex_unlock(&st->buf_lock);
48 
49 	return ret;
50 }
51 
52 /**
53  * adis16204_spi_write_reg_16() - write 2 bytes to a pair of registers
54  * @indio_dev: iio device associated with child of actual device
55  * @reg_address: the address of the lower of the two registers. Second register
56  *               is assumed to have address one greater.
57  * @val: value to be written
58  **/
adis16204_spi_write_reg_16(struct iio_dev * indio_dev,u8 lower_reg_address,u16 value)59 static int adis16204_spi_write_reg_16(struct iio_dev *indio_dev,
60 		u8 lower_reg_address,
61 		u16 value)
62 {
63 	int ret;
64 	struct spi_message msg;
65 	struct adis16204_state *st = iio_priv(indio_dev);
66 	struct spi_transfer xfers[] = {
67 		{
68 			.tx_buf = st->tx,
69 			.bits_per_word = 8,
70 			.len = 2,
71 			.cs_change = 1,
72 		}, {
73 			.tx_buf = st->tx + 2,
74 			.bits_per_word = 8,
75 			.len = 2,
76 			.cs_change = 1,
77 		},
78 	};
79 
80 	mutex_lock(&st->buf_lock);
81 	st->tx[0] = ADIS16204_WRITE_REG(lower_reg_address);
82 	st->tx[1] = value & 0xFF;
83 	st->tx[2] = ADIS16204_WRITE_REG(lower_reg_address + 1);
84 	st->tx[3] = (value >> 8) & 0xFF;
85 
86 	spi_message_init(&msg);
87 	spi_message_add_tail(&xfers[0], &msg);
88 	spi_message_add_tail(&xfers[1], &msg);
89 	ret = spi_sync(st->us, &msg);
90 	mutex_unlock(&st->buf_lock);
91 
92 	return ret;
93 }
94 
95 /**
96  * adis16204_spi_read_reg_16() - read 2 bytes from a 16-bit register
97  * @indio_dev: iio device associated with child of actual device
98  * @reg_address: the address of the lower of the two registers. Second register
99  *               is assumed to have address one greater.
100  * @val: somewhere to pass back the value read
101  **/
adis16204_spi_read_reg_16(struct iio_dev * indio_dev,u8 lower_reg_address,u16 * val)102 static int adis16204_spi_read_reg_16(struct iio_dev *indio_dev,
103 				     u8 lower_reg_address,
104 				     u16 *val)
105 {
106 	struct spi_message msg;
107 	struct adis16204_state *st = iio_priv(indio_dev);
108 	int ret;
109 	struct spi_transfer xfers[] = {
110 		{
111 			.tx_buf = st->tx,
112 			.bits_per_word = 8,
113 			.len = 2,
114 			.cs_change = 1,
115 			.delay_usecs = 20,
116 		}, {
117 			.rx_buf = st->rx,
118 			.bits_per_word = 8,
119 			.len = 2,
120 			.delay_usecs = 20,
121 		},
122 	};
123 
124 	mutex_lock(&st->buf_lock);
125 	st->tx[0] = ADIS16204_READ_REG(lower_reg_address);
126 	st->tx[1] = 0;
127 
128 	spi_message_init(&msg);
129 	spi_message_add_tail(&xfers[0], &msg);
130 	spi_message_add_tail(&xfers[1], &msg);
131 	ret = spi_sync(st->us, &msg);
132 	if (ret) {
133 		dev_err(&st->us->dev, "problem when reading 16 bit register 0x%02X",
134 				lower_reg_address);
135 		goto error_ret;
136 	}
137 	*val = (st->rx[0] << 8) | st->rx[1];
138 
139 error_ret:
140 	mutex_unlock(&st->buf_lock);
141 	return ret;
142 }
143 
adis16204_check_status(struct iio_dev * indio_dev)144 static int adis16204_check_status(struct iio_dev *indio_dev)
145 {
146 	u16 status;
147 	int ret;
148 
149 	ret = adis16204_spi_read_reg_16(indio_dev,
150 					ADIS16204_DIAG_STAT, &status);
151 	if (ret < 0) {
152 		dev_err(&indio_dev->dev, "Reading status failed\n");
153 		goto error_ret;
154 	}
155 	ret = status & 0x1F;
156 
157 	if (status & ADIS16204_DIAG_STAT_SELFTEST_FAIL)
158 		dev_err(&indio_dev->dev, "Self test failure\n");
159 	if (status & ADIS16204_DIAG_STAT_SPI_FAIL)
160 		dev_err(&indio_dev->dev, "SPI failure\n");
161 	if (status & ADIS16204_DIAG_STAT_FLASH_UPT)
162 		dev_err(&indio_dev->dev, "Flash update failed\n");
163 	if (status & ADIS16204_DIAG_STAT_POWER_HIGH)
164 		dev_err(&indio_dev->dev, "Power supply above 3.625V\n");
165 	if (status & ADIS16204_DIAG_STAT_POWER_LOW)
166 		dev_err(&indio_dev->dev, "Power supply below 2.975V\n");
167 
168 error_ret:
169 	return ret;
170 }
171 
adis16204_read_14bit_signed(struct device * dev,struct device_attribute * attr,char * buf)172 static ssize_t adis16204_read_14bit_signed(struct device *dev,
173 		struct device_attribute *attr,
174 		char *buf)
175 {
176 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
177 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
178 	s16 val = 0;
179 	ssize_t ret;
180 
181 	mutex_lock(&indio_dev->mlock);
182 
183 	ret = adis16204_spi_read_reg_16(indio_dev,
184 					this_attr->address, (u16 *)&val);
185 	if (!ret) {
186 		if (val & ADIS16204_ERROR_ACTIVE)
187 			adis16204_check_status(indio_dev);
188 
189 		val = ((s16)(val << 2) >> 2);
190 		ret = sprintf(buf, "%d\n", val);
191 	}
192 
193 	mutex_unlock(&indio_dev->mlock);
194 
195 	return ret;
196 }
197 
adis16204_reset(struct iio_dev * indio_dev)198 static int adis16204_reset(struct iio_dev *indio_dev)
199 {
200 	int ret;
201 	ret = adis16204_spi_write_reg_8(indio_dev,
202 			ADIS16204_GLOB_CMD,
203 			ADIS16204_GLOB_CMD_SW_RESET);
204 	if (ret)
205 		dev_err(&indio_dev->dev, "problem resetting device");
206 
207 	return ret;
208 }
209 
adis16204_write_reset(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)210 static ssize_t adis16204_write_reset(struct device *dev,
211 		struct device_attribute *attr,
212 		const char *buf, size_t len)
213 {
214 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
215 
216 	if (len < 1)
217 		return -EINVAL;
218 	switch (buf[0]) {
219 	case '1':
220 	case 'y':
221 	case 'Y':
222 		return adis16204_reset(indio_dev);
223 	}
224 	return -EINVAL;
225 }
226 
adis16204_set_irq(struct iio_dev * indio_dev,bool enable)227 int adis16204_set_irq(struct iio_dev *indio_dev, bool enable)
228 {
229 	int ret = 0;
230 	u16 msc;
231 
232 	ret = adis16204_spi_read_reg_16(indio_dev, ADIS16204_MSC_CTRL, &msc);
233 	if (ret)
234 		goto error_ret;
235 
236 	msc |= ADIS16204_MSC_CTRL_ACTIVE_HIGH;
237 	msc &= ~ADIS16204_MSC_CTRL_DATA_RDY_DIO2;
238 	if (enable)
239 		msc |= ADIS16204_MSC_CTRL_DATA_RDY_EN;
240 	else
241 		msc &= ~ADIS16204_MSC_CTRL_DATA_RDY_EN;
242 
243 	ret = adis16204_spi_write_reg_16(indio_dev, ADIS16204_MSC_CTRL, msc);
244 
245 error_ret:
246 	return ret;
247 }
248 
adis16204_self_test(struct iio_dev * indio_dev)249 static int adis16204_self_test(struct iio_dev *indio_dev)
250 {
251 	int ret;
252 	ret = adis16204_spi_write_reg_16(indio_dev,
253 			ADIS16204_MSC_CTRL,
254 			ADIS16204_MSC_CTRL_SELF_TEST_EN);
255 	if (ret) {
256 		dev_err(&indio_dev->dev, "problem starting self test");
257 		goto err_ret;
258 	}
259 
260 	adis16204_check_status(indio_dev);
261 
262 err_ret:
263 	return ret;
264 }
265 
adis16204_initial_setup(struct iio_dev * indio_dev)266 static int adis16204_initial_setup(struct iio_dev *indio_dev)
267 {
268 	int ret;
269 
270 	/* Disable IRQ */
271 	ret = adis16204_set_irq(indio_dev, false);
272 	if (ret) {
273 		dev_err(&indio_dev->dev, "disable irq failed");
274 		goto err_ret;
275 	}
276 
277 	/* Do self test */
278 	ret = adis16204_self_test(indio_dev);
279 	if (ret) {
280 		dev_err(&indio_dev->dev, "self test failure");
281 		goto err_ret;
282 	}
283 
284 	/* Read status register to check the result */
285 	ret = adis16204_check_status(indio_dev);
286 	if (ret) {
287 		adis16204_reset(indio_dev);
288 		dev_err(&indio_dev->dev, "device not playing ball -> reset");
289 		msleep(ADIS16204_STARTUP_DELAY);
290 		ret = adis16204_check_status(indio_dev);
291 		if (ret) {
292 			dev_err(&indio_dev->dev, "giving up");
293 			goto err_ret;
294 		}
295 	}
296 
297 err_ret:
298 	return ret;
299 }
300 
301 /* Unique to this driver currently */
302 #define IIO_DEV_ATTR_ACCEL_XY(_show, _addr)			\
303 	IIO_DEVICE_ATTR(in_accel_xy, S_IRUGO, _show, NULL, _addr)
304 #define IIO_DEV_ATTR_ACCEL_XYPEAK(_show, _addr)		\
305 	IIO_DEVICE_ATTR(in_accel_xypeak, S_IRUGO, _show, NULL, _addr)
306 
307 static IIO_DEV_ATTR_ACCEL_XY(adis16204_read_14bit_signed,
308 		ADIS16204_XY_RSS_OUT);
309 static IIO_DEV_ATTR_ACCEL_XYPEAK(adis16204_read_14bit_signed,
310 		ADIS16204_XY_PEAK_OUT);
311 static IIO_CONST_ATTR(in_accel_xy_scale, "0.017125");
312 
313 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16204_write_reset, 0);
314 
315 enum adis16204_channel {
316 	in_supply,
317 	in_aux,
318 	temp,
319 	accel_x,
320 	accel_y,
321 };
322 
323 static u8 adis16204_addresses[5][3] = {
324 	[in_supply] = { ADIS16204_SUPPLY_OUT },
325 	[in_aux] = { ADIS16204_AUX_ADC },
326 	[temp] = { ADIS16204_TEMP_OUT },
327 	[accel_x] = { ADIS16204_XACCL_OUT, ADIS16204_XACCL_NULL,
328 		      ADIS16204_X_PEAK_OUT },
329 	[accel_y] = { ADIS16204_XACCL_OUT, ADIS16204_YACCL_NULL,
330 		      ADIS16204_Y_PEAK_OUT },
331 };
332 
adis16204_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)333 static int adis16204_read_raw(struct iio_dev *indio_dev,
334 			      struct iio_chan_spec const *chan,
335 			      int *val, int *val2,
336 			      long mask)
337 {
338 	int ret;
339 	int bits;
340 	u8 addr;
341 	s16 val16;
342 	int addrind;
343 
344 	switch (mask) {
345 	case 0:
346 		mutex_lock(&indio_dev->mlock);
347 		addr = adis16204_addresses[chan->address][0];
348 		ret = adis16204_spi_read_reg_16(indio_dev, addr, &val16);
349 		if (ret) {
350 			mutex_unlock(&indio_dev->mlock);
351 			return ret;
352 		}
353 
354 		if (val16 & ADIS16204_ERROR_ACTIVE) {
355 			ret = adis16204_check_status(indio_dev);
356 			if (ret) {
357 				mutex_unlock(&indio_dev->mlock);
358 				return ret;
359 			}
360 		}
361 		val16 = val16 & ((1 << chan->scan_type.realbits) - 1);
362 		if (chan->scan_type.sign == 's')
363 			val16 = (s16)(val16 <<
364 				      (16 - chan->scan_type.realbits)) >>
365 				(16 - chan->scan_type.realbits);
366 		*val = val16;
367 		mutex_unlock(&indio_dev->mlock);
368 		return IIO_VAL_INT;
369 	case IIO_CHAN_INFO_SCALE:
370 		switch (chan->type) {
371 		case IIO_VOLTAGE:
372 			*val = 0;
373 			if (chan->channel == 0)
374 				*val2 = 1220;
375 			else
376 				*val2 = 610;
377 			return IIO_VAL_INT_PLUS_MICRO;
378 		case IIO_TEMP:
379 			*val = 0;
380 			*val2 = -470000;
381 			return IIO_VAL_INT_PLUS_MICRO;
382 		case IIO_ACCEL:
383 			*val = 0;
384 			if (chan->channel == 'x')
385 				*val2 = 17125;
386 			else
387 				*val2 = 8407;
388 			return IIO_VAL_INT_PLUS_MICRO;
389 		default:
390 			return -EINVAL;
391 		}
392 		break;
393 	case IIO_CHAN_INFO_OFFSET:
394 		*val = 25;
395 		return IIO_VAL_INT;
396 	case IIO_CHAN_INFO_CALIBBIAS:
397 	case IIO_CHAN_INFO_PEAK:
398 		if (mask == IIO_CHAN_INFO_CALIBBIAS) {
399 			bits = 12;
400 			addrind = 1;
401 		} else { /* PEAK_SEPARATE */
402 			bits = 14;
403 			addrind = 2;
404 		}
405 		mutex_lock(&indio_dev->mlock);
406 		addr = adis16204_addresses[chan->address][addrind];
407 		ret = adis16204_spi_read_reg_16(indio_dev, addr, &val16);
408 		if (ret) {
409 			mutex_unlock(&indio_dev->mlock);
410 			return ret;
411 		}
412 		val16 &= (1 << bits) - 1;
413 		val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
414 		*val = val16;
415 		mutex_unlock(&indio_dev->mlock);
416 		return IIO_VAL_INT;
417 	}
418 	return -EINVAL;
419 }
420 
adis16204_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)421 static int adis16204_write_raw(struct iio_dev *indio_dev,
422 			       struct iio_chan_spec const *chan,
423 			       int val,
424 			       int val2,
425 			       long mask)
426 {
427 	int bits;
428 	s16 val16;
429 	u8 addr;
430 	switch (mask) {
431 	case IIO_CHAN_INFO_CALIBBIAS:
432 		switch (chan->type) {
433 		case IIO_ACCEL:
434 			bits = 12;
435 			break;
436 		default:
437 			return -EINVAL;
438 		};
439 		val16 = val & ((1 << bits) - 1);
440 		addr = adis16204_addresses[chan->address][1];
441 		return adis16204_spi_write_reg_16(indio_dev, addr, val16);
442 	}
443 	return -EINVAL;
444 }
445 
446 static struct iio_chan_spec adis16204_channels[] = {
447 	IIO_CHAN(IIO_VOLTAGE, 0, 0, 0, "supply", 0, 0,
448 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
449 		 in_supply, ADIS16204_SCAN_SUPPLY,
450 		 IIO_ST('u', 12, 16, 0), 0),
451 	IIO_CHAN(IIO_VOLTAGE, 0, 1, 0, NULL, 1, 0,
452 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
453 		 in_aux, ADIS16204_SCAN_AUX_ADC,
454 		 IIO_ST('u', 12, 16, 0), 0),
455 	IIO_CHAN(IIO_TEMP, 0, 1, 0, NULL, 0, 0,
456 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT |
457 		 IIO_CHAN_INFO_OFFSET_SEPARATE_BIT,
458 		 temp, ADIS16204_SCAN_TEMP,
459 		 IIO_ST('u', 12, 16, 0), 0),
460 	IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_X,
461 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT |
462 		 IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
463 		 IIO_CHAN_INFO_PEAK_SEPARATE_BIT,
464 		 accel_x, ADIS16204_SCAN_ACC_X,
465 		 IIO_ST('s', 14, 16, 0), 0),
466 	IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Y,
467 		 IIO_CHAN_INFO_SCALE_SEPARATE_BIT |
468 		 IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
469 		 IIO_CHAN_INFO_PEAK_SEPARATE_BIT,
470 		 accel_y, ADIS16204_SCAN_ACC_Y,
471 		 IIO_ST('s', 14, 16, 0), 0),
472 	IIO_CHAN_SOFT_TIMESTAMP(5),
473 };
474 
475 static struct attribute *adis16204_attributes[] = {
476 	&iio_dev_attr_reset.dev_attr.attr,
477 	&iio_dev_attr_in_accel_xy.dev_attr.attr,
478 	&iio_dev_attr_in_accel_xypeak.dev_attr.attr,
479 	&iio_const_attr_in_accel_xy_scale.dev_attr.attr,
480 	NULL
481 };
482 
483 static const struct attribute_group adis16204_attribute_group = {
484 	.attrs = adis16204_attributes,
485 };
486 
487 static const struct iio_info adis16204_info = {
488 	.attrs = &adis16204_attribute_group,
489 	.read_raw = &adis16204_read_raw,
490 	.write_raw = &adis16204_write_raw,
491 	.driver_module = THIS_MODULE,
492 };
493 
adis16204_probe(struct spi_device * spi)494 static int __devinit adis16204_probe(struct spi_device *spi)
495 {
496 	int ret;
497 	struct adis16204_state *st;
498 	struct iio_dev *indio_dev;
499 
500 	/* setup the industrialio driver allocated elements */
501 	indio_dev = iio_allocate_device(sizeof(*st));
502 	if (indio_dev == NULL) {
503 		ret = -ENOMEM;
504 		goto error_ret;
505 	}
506 	st = iio_priv(indio_dev);
507 	/* this is only used for removal purposes */
508 	spi_set_drvdata(spi, indio_dev);
509 	st->us = spi;
510 	mutex_init(&st->buf_lock);
511 
512 	indio_dev->name = spi->dev.driver->name;
513 	indio_dev->dev.parent = &spi->dev;
514 	indio_dev->info = &adis16204_info;
515 	indio_dev->channels = adis16204_channels;
516 	indio_dev->num_channels = ARRAY_SIZE(adis16204_channels);
517 	indio_dev->modes = INDIO_DIRECT_MODE;
518 
519 	ret = adis16204_configure_ring(indio_dev);
520 	if (ret)
521 		goto error_free_dev;
522 
523 	ret = iio_buffer_register(indio_dev,
524 				  adis16204_channels,
525 				  ARRAY_SIZE(adis16204_channels));
526 	if (ret) {
527 		printk(KERN_ERR "failed to initialize the ring\n");
528 		goto error_unreg_ring_funcs;
529 	}
530 
531 	if (spi->irq) {
532 		ret = adis16204_probe_trigger(indio_dev);
533 		if (ret)
534 			goto error_uninitialize_ring;
535 	}
536 
537 	/* Get the device into a sane initial state */
538 	ret = adis16204_initial_setup(indio_dev);
539 	if (ret)
540 		goto error_remove_trigger;
541 	ret = iio_device_register(indio_dev);
542 	if (ret)
543 		goto error_remove_trigger;
544 
545 	return 0;
546 
547 error_remove_trigger:
548 	adis16204_remove_trigger(indio_dev);
549 error_uninitialize_ring:
550 	iio_buffer_unregister(indio_dev);
551 error_unreg_ring_funcs:
552 	adis16204_unconfigure_ring(indio_dev);
553 error_free_dev:
554 	iio_free_device(indio_dev);
555 error_ret:
556 	return ret;
557 }
558 
adis16204_remove(struct spi_device * spi)559 static int adis16204_remove(struct spi_device *spi)
560 {
561 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
562 
563 	iio_device_unregister(indio_dev);
564 	adis16204_remove_trigger(indio_dev);
565 	iio_buffer_unregister(indio_dev);
566 	adis16204_unconfigure_ring(indio_dev);
567 	iio_free_device(indio_dev);
568 
569 	return 0;
570 }
571 
572 static struct spi_driver adis16204_driver = {
573 	.driver = {
574 		.name = "adis16204",
575 		.owner = THIS_MODULE,
576 	},
577 	.probe = adis16204_probe,
578 	.remove = __devexit_p(adis16204_remove),
579 };
580 module_spi_driver(adis16204_driver);
581 
582 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
583 MODULE_DESCRIPTION("ADIS16204 High-g Digital Impact Sensor and Recorder");
584 MODULE_LICENSE("GPL v2");
585 MODULE_ALIAS("spi:adis16204");
586