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 **/
32static 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 **/
56static 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 **/
98static 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
135error_ret:
136	mutex_unlock(&st->buf_lock);
137	return ret;
138}
139
140static 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
165error_ret:
166	return ret;
167}
168
169static 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
181static 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
197int 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
215error_ret:
216	return ret;
217}
218
219static 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
232err_ret:
233	return ret;
234}
235
236static 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
267err_ret:
268	return ret;
269}
270
271enum adis16203_chan {
272	in_supply,
273	in_aux,
274	incli_x,
275	incli_y,
276	temp,
277};
278
279static 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
287static 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
298static 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
374static 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
401static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16203_write_reset, 0);
402
403static struct attribute *adis16203_attributes[] = {
404	&iio_dev_attr_reset.dev_attr.attr,
405	NULL
406};
407
408static const struct attribute_group adis16203_attribute_group = {
409	.attrs = adis16203_attributes,
410};
411
412static 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
419static 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
473error_remove_trigger:
474	adis16203_remove_trigger(indio_dev);
475error_uninitialize_ring:
476	iio_buffer_unregister(indio_dev);
477error_unreg_ring_funcs:
478	adis16203_unconfigure_ring(indio_dev);
479error_free_dev:
480	iio_free_device(indio_dev);
481error_ret:
482	return ret;
483}
484
485static 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
498static 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};
506module_spi_driver(adis16203_driver);
507
508MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
509MODULE_DESCRIPTION("Analog Devices ADIS16203 Programmable Digital Vibration Sensor driver");
510MODULE_LICENSE("GPL v2");
511MODULE_ALIAS("spi:adis16203");
512