1 /*
2  * lis3l02dq.c	support STMicroelectronics LISD02DQ
3  *		3d 2g Linear Accelerometers via SPI
4  *
5  * Copyright (c) 2007 Jonathan Cameron <jic23@kernel.org>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * Settings:
12  * 16 bit left justified mode used.
13  */
14 
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/gpio.h>
18 #include <linux/of_gpio.h>
19 #include <linux/mutex.h>
20 #include <linux/device.h>
21 #include <linux/kernel.h>
22 #include <linux/spi/spi.h>
23 #include <linux/slab.h>
24 #include <linux/sysfs.h>
25 #include <linux/module.h>
26 
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/iio/events.h>
30 #include <linux/iio/buffer.h>
31 
32 #include "lis3l02dq.h"
33 
34 /* At the moment the spi framework doesn't allow global setting of cs_change.
35  * It's in the likely to be added comment at the top of spi.h.
36  * This means that use cannot be made of spi_write etc.
37  */
38 /* direct copy of the irq_default_primary_handler */
39 #ifndef CONFIG_IIO_BUFFER
lis3l02dq_nobuffer(int irq,void * private)40 static irqreturn_t lis3l02dq_nobuffer(int irq, void *private)
41 {
42 	return IRQ_WAKE_THREAD;
43 }
44 #endif
45 
46 /**
47  * lis3l02dq_spi_read_reg_8() - read single byte from a single register
48  * @indio_dev: iio_dev for this actual device
49  * @reg_address: the address of the register to be read
50  * @val: pass back the resulting value
51  **/
lis3l02dq_spi_read_reg_8(struct iio_dev * indio_dev,u8 reg_address,u8 * val)52 int lis3l02dq_spi_read_reg_8(struct iio_dev *indio_dev,
53 			     u8 reg_address, u8 *val)
54 {
55 	struct lis3l02dq_state *st = iio_priv(indio_dev);
56 	int ret;
57 	struct spi_transfer xfer = {
58 		.tx_buf = st->tx,
59 		.rx_buf = st->rx,
60 		.bits_per_word = 8,
61 		.len = 2,
62 	};
63 
64 	mutex_lock(&st->buf_lock);
65 	st->tx[0] = LIS3L02DQ_READ_REG(reg_address);
66 	st->tx[1] = 0;
67 
68 	ret = spi_sync_transfer(st->us, &xfer, 1);
69 	*val = st->rx[1];
70 	mutex_unlock(&st->buf_lock);
71 
72 	return ret;
73 }
74 
75 /**
76  * lis3l02dq_spi_write_reg_8() - write single byte to a register
77  * @indio_dev: iio_dev for this device
78  * @reg_address: the address of the register to be written
79  * @val: the value to write
80  **/
lis3l02dq_spi_write_reg_8(struct iio_dev * indio_dev,u8 reg_address,u8 val)81 int lis3l02dq_spi_write_reg_8(struct iio_dev *indio_dev,
82 			      u8 reg_address,
83 			      u8 val)
84 {
85 	int ret;
86 	struct lis3l02dq_state *st = iio_priv(indio_dev);
87 
88 	mutex_lock(&st->buf_lock);
89 	st->tx[0] = LIS3L02DQ_WRITE_REG(reg_address);
90 	st->tx[1] = val;
91 	ret = spi_write(st->us, st->tx, 2);
92 	mutex_unlock(&st->buf_lock);
93 
94 	return ret;
95 }
96 
97 /**
98  * lisl302dq_spi_write_reg_s16() - write 2 bytes to a pair of registers
99  * @indio_dev: iio_dev for this device
100  * @lower_reg_address: the address of the lower of the two registers.
101  *               Second register is assumed to have address one greater.
102  * @value: value to be written
103  **/
lis3l02dq_spi_write_reg_s16(struct iio_dev * indio_dev,u8 lower_reg_address,s16 value)104 static int lis3l02dq_spi_write_reg_s16(struct iio_dev *indio_dev,
105 				       u8 lower_reg_address,
106 				       s16 value)
107 {
108 	int ret;
109 	struct lis3l02dq_state *st = iio_priv(indio_dev);
110 	struct spi_transfer xfers[] = { {
111 			.tx_buf = st->tx,
112 			.bits_per_word = 8,
113 			.len = 2,
114 			.cs_change = 1,
115 		}, {
116 			.tx_buf = st->tx + 2,
117 			.bits_per_word = 8,
118 			.len = 2,
119 		},
120 	};
121 
122 	mutex_lock(&st->buf_lock);
123 	st->tx[0] = LIS3L02DQ_WRITE_REG(lower_reg_address);
124 	st->tx[1] = value & 0xFF;
125 	st->tx[2] = LIS3L02DQ_WRITE_REG(lower_reg_address + 1);
126 	st->tx[3] = (value >> 8) & 0xFF;
127 
128 	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
129 	mutex_unlock(&st->buf_lock);
130 
131 	return ret;
132 }
133 
lis3l02dq_read_reg_s16(struct iio_dev * indio_dev,u8 lower_reg_address,int * val)134 static int lis3l02dq_read_reg_s16(struct iio_dev *indio_dev,
135 				  u8 lower_reg_address,
136 				  int *val)
137 {
138 	struct lis3l02dq_state *st = iio_priv(indio_dev);
139 	int ret;
140 	s16 tempval;
141 	struct spi_transfer xfers[] = { {
142 			.tx_buf = st->tx,
143 			.rx_buf = st->rx,
144 			.bits_per_word = 8,
145 			.len = 2,
146 			.cs_change = 1,
147 		}, {
148 			.tx_buf = st->tx + 2,
149 			.rx_buf = st->rx + 2,
150 			.bits_per_word = 8,
151 			.len = 2,
152 		},
153 	};
154 
155 	mutex_lock(&st->buf_lock);
156 	st->tx[0] = LIS3L02DQ_READ_REG(lower_reg_address);
157 	st->tx[1] = 0;
158 	st->tx[2] = LIS3L02DQ_READ_REG(lower_reg_address + 1);
159 	st->tx[3] = 0;
160 
161 	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
162 	if (ret) {
163 		dev_err(&st->us->dev, "problem when reading 16 bit register");
164 		goto error_ret;
165 	}
166 	tempval = (s16)(st->rx[1]) | ((s16)(st->rx[3]) << 8);
167 
168 	*val = tempval;
169 error_ret:
170 	mutex_unlock(&st->buf_lock);
171 	return ret;
172 }
173 
174 enum lis3l02dq_rm_ind {
175 	LIS3L02DQ_ACCEL,
176 	LIS3L02DQ_GAIN,
177 	LIS3L02DQ_BIAS,
178 };
179 
180 static u8 lis3l02dq_axis_map[3][3] = {
181 	[LIS3L02DQ_ACCEL] = { LIS3L02DQ_REG_OUT_X_L_ADDR,
182 			      LIS3L02DQ_REG_OUT_Y_L_ADDR,
183 			      LIS3L02DQ_REG_OUT_Z_L_ADDR },
184 	[LIS3L02DQ_GAIN] = { LIS3L02DQ_REG_GAIN_X_ADDR,
185 			     LIS3L02DQ_REG_GAIN_Y_ADDR,
186 			     LIS3L02DQ_REG_GAIN_Z_ADDR },
187 	[LIS3L02DQ_BIAS] = { LIS3L02DQ_REG_OFFSET_X_ADDR,
188 			     LIS3L02DQ_REG_OFFSET_Y_ADDR,
189 			     LIS3L02DQ_REG_OFFSET_Z_ADDR }
190 };
191 
lis3l02dq_read_thresh(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,enum iio_event_info info,int * val,int * val2)192 static int lis3l02dq_read_thresh(struct iio_dev *indio_dev,
193 				 const struct iio_chan_spec *chan,
194 				 enum iio_event_type type,
195 				 enum iio_event_direction dir,
196 				 enum iio_event_info info,
197 				 int *val, int *val2)
198 {
199 	int ret;
200 
201 	ret = lis3l02dq_read_reg_s16(indio_dev, LIS3L02DQ_REG_THS_L_ADDR, val);
202 	if (ret)
203 		return ret;
204 	return IIO_VAL_INT;
205 }
206 
lis3l02dq_write_thresh(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,enum iio_event_info info,int val,int val2)207 static int lis3l02dq_write_thresh(struct iio_dev *indio_dev,
208 				  const struct iio_chan_spec *chan,
209 				  enum iio_event_type type,
210 				  enum iio_event_direction dir,
211 				  enum iio_event_info info,
212 				  int val, int val2)
213 {
214 	u16 value = val;
215 
216 	return lis3l02dq_spi_write_reg_s16(indio_dev,
217 					   LIS3L02DQ_REG_THS_L_ADDR,
218 					   value);
219 }
220 
lis3l02dq_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)221 static int lis3l02dq_write_raw(struct iio_dev *indio_dev,
222 			       struct iio_chan_spec const *chan,
223 			       int val,
224 			       int val2,
225 			       long mask)
226 {
227 	int ret = -EINVAL, reg;
228 	u8 uval;
229 	s8 sval;
230 
231 	switch (mask) {
232 	case IIO_CHAN_INFO_CALIBBIAS:
233 		if (val > 255 || val < -256)
234 			return -EINVAL;
235 		sval = val;
236 		reg = lis3l02dq_axis_map[LIS3L02DQ_BIAS][chan->address];
237 		ret = lis3l02dq_spi_write_reg_8(indio_dev, reg, sval);
238 		break;
239 	case IIO_CHAN_INFO_CALIBSCALE:
240 		if (val & ~0xFF)
241 			return -EINVAL;
242 		uval = val;
243 		reg = lis3l02dq_axis_map[LIS3L02DQ_GAIN][chan->address];
244 		ret = lis3l02dq_spi_write_reg_8(indio_dev, reg, uval);
245 		break;
246 	}
247 	return ret;
248 }
249 
lis3l02dq_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)250 static int lis3l02dq_read_raw(struct iio_dev *indio_dev,
251 			      struct iio_chan_spec const *chan,
252 			      int *val,
253 			      int *val2,
254 			      long mask)
255 {
256 	u8 utemp;
257 	s8 stemp;
258 	ssize_t ret = 0;
259 	u8 reg;
260 
261 	switch (mask) {
262 	case IIO_CHAN_INFO_RAW:
263 		/* Take the iio_dev status lock */
264 		mutex_lock(&indio_dev->mlock);
265 		if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
266 			ret = -EBUSY;
267 		} else {
268 			reg = lis3l02dq_axis_map
269 				[LIS3L02DQ_ACCEL][chan->address];
270 			ret = lis3l02dq_read_reg_s16(indio_dev, reg, val);
271 		}
272 		mutex_unlock(&indio_dev->mlock);
273 		if (ret < 0)
274 			goto error_ret;
275 		return IIO_VAL_INT;
276 	case IIO_CHAN_INFO_SCALE:
277 		*val = 0;
278 		*val2 = 9580;
279 		return IIO_VAL_INT_PLUS_MICRO;
280 	case IIO_CHAN_INFO_CALIBSCALE:
281 		reg = lis3l02dq_axis_map[LIS3L02DQ_GAIN][chan->address];
282 		ret = lis3l02dq_spi_read_reg_8(indio_dev, reg, &utemp);
283 		if (ret)
284 			goto error_ret;
285 		/* to match with what previous code does */
286 		*val = utemp;
287 		return IIO_VAL_INT;
288 
289 	case IIO_CHAN_INFO_CALIBBIAS:
290 		reg = lis3l02dq_axis_map[LIS3L02DQ_BIAS][chan->address];
291 		ret = lis3l02dq_spi_read_reg_8(indio_dev, reg, (u8 *)&stemp);
292 		/* to match with what previous code does */
293 		*val = stemp;
294 		return IIO_VAL_INT;
295 	}
296 error_ret:
297 	return ret;
298 }
299 
lis3l02dq_read_frequency(struct device * dev,struct device_attribute * attr,char * buf)300 static ssize_t lis3l02dq_read_frequency(struct device *dev,
301 					struct device_attribute *attr,
302 					char *buf)
303 {
304 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
305 	int ret, len = 0;
306 	s8 t;
307 
308 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
309 				       LIS3L02DQ_REG_CTRL_1_ADDR,
310 				       (u8 *)&t);
311 	if (ret)
312 		return ret;
313 	t &= LIS3L02DQ_DEC_MASK;
314 	switch (t) {
315 	case LIS3L02DQ_REG_CTRL_1_DF_128:
316 		len = sprintf(buf, "280\n");
317 		break;
318 	case LIS3L02DQ_REG_CTRL_1_DF_64:
319 		len = sprintf(buf, "560\n");
320 		break;
321 	case LIS3L02DQ_REG_CTRL_1_DF_32:
322 		len = sprintf(buf, "1120\n");
323 		break;
324 	case LIS3L02DQ_REG_CTRL_1_DF_8:
325 		len = sprintf(buf, "4480\n");
326 		break;
327 	}
328 	return len;
329 }
330 
lis3l02dq_write_frequency(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)331 static ssize_t lis3l02dq_write_frequency(struct device *dev,
332 					 struct device_attribute *attr,
333 					 const char *buf,
334 					 size_t len)
335 {
336 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
337 	unsigned long val;
338 	int ret;
339 	u8 t;
340 
341 	ret = kstrtoul(buf, 10, &val);
342 	if (ret)
343 		return ret;
344 
345 	mutex_lock(&indio_dev->mlock);
346 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
347 				       LIS3L02DQ_REG_CTRL_1_ADDR,
348 				       &t);
349 	if (ret)
350 		goto error_ret_mutex;
351 	/* Wipe the bits clean */
352 	t &= ~LIS3L02DQ_DEC_MASK;
353 	switch (val) {
354 	case 280:
355 		t |= LIS3L02DQ_REG_CTRL_1_DF_128;
356 		break;
357 	case 560:
358 		t |= LIS3L02DQ_REG_CTRL_1_DF_64;
359 		break;
360 	case 1120:
361 		t |= LIS3L02DQ_REG_CTRL_1_DF_32;
362 		break;
363 	case 4480:
364 		t |= LIS3L02DQ_REG_CTRL_1_DF_8;
365 		break;
366 	default:
367 		ret = -EINVAL;
368 		goto error_ret_mutex;
369 	}
370 
371 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
372 					LIS3L02DQ_REG_CTRL_1_ADDR,
373 					t);
374 
375 error_ret_mutex:
376 	mutex_unlock(&indio_dev->mlock);
377 
378 	return ret ? ret : len;
379 }
380 
lis3l02dq_initial_setup(struct iio_dev * indio_dev)381 static int lis3l02dq_initial_setup(struct iio_dev *indio_dev)
382 {
383 	struct lis3l02dq_state *st = iio_priv(indio_dev);
384 	int ret;
385 	u8 val, valtest;
386 
387 	st->us->mode = SPI_MODE_3;
388 
389 	spi_setup(st->us);
390 
391 	val = LIS3L02DQ_DEFAULT_CTRL1;
392 	/* Write suitable defaults to ctrl1 */
393 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
394 					LIS3L02DQ_REG_CTRL_1_ADDR,
395 					val);
396 	if (ret) {
397 		dev_err(&st->us->dev, "problem with setup control register 1");
398 		goto err_ret;
399 	}
400 	/* Repeat as sometimes doesn't work first time? */
401 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
402 					LIS3L02DQ_REG_CTRL_1_ADDR,
403 					val);
404 	if (ret) {
405 		dev_err(&st->us->dev, "problem with setup control register 1");
406 		goto err_ret;
407 	}
408 
409 	/* Read back to check this has worked acts as loose test of correct
410 	 * chip */
411 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
412 				       LIS3L02DQ_REG_CTRL_1_ADDR,
413 				       &valtest);
414 	if (ret || (valtest != val)) {
415 		dev_err(&indio_dev->dev,
416 			"device not playing ball %d %d\n", valtest, val);
417 		ret = -EINVAL;
418 		goto err_ret;
419 	}
420 
421 	val = LIS3L02DQ_DEFAULT_CTRL2;
422 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
423 					LIS3L02DQ_REG_CTRL_2_ADDR,
424 					val);
425 	if (ret) {
426 		dev_err(&st->us->dev, "problem with setup control register 2");
427 		goto err_ret;
428 	}
429 
430 	val = LIS3L02DQ_REG_WAKE_UP_CFG_LATCH_SRC;
431 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
432 					LIS3L02DQ_REG_WAKE_UP_CFG_ADDR,
433 					val);
434 	if (ret)
435 		dev_err(&st->us->dev, "problem with interrupt cfg register");
436 err_ret:
437 
438 	return ret;
439 }
440 
441 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
442 			      lis3l02dq_read_frequency,
443 			      lis3l02dq_write_frequency);
444 
445 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("280 560 1120 4480");
446 
lis3l02dq_event_handler(int irq,void * private)447 static irqreturn_t lis3l02dq_event_handler(int irq, void *private)
448 {
449 	struct iio_dev *indio_dev = private;
450 	u8 t;
451 
452 	s64 timestamp = iio_get_time_ns();
453 
454 	lis3l02dq_spi_read_reg_8(indio_dev,
455 				 LIS3L02DQ_REG_WAKE_UP_SRC_ADDR,
456 				 &t);
457 
458 	if (t & LIS3L02DQ_REG_WAKE_UP_SRC_INTERRUPT_Z_HIGH)
459 		iio_push_event(indio_dev,
460 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
461 						  0,
462 						  IIO_MOD_Z,
463 						  IIO_EV_TYPE_THRESH,
464 						  IIO_EV_DIR_RISING),
465 			       timestamp);
466 
467 	if (t & LIS3L02DQ_REG_WAKE_UP_SRC_INTERRUPT_Z_LOW)
468 		iio_push_event(indio_dev,
469 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
470 						  0,
471 						  IIO_MOD_Z,
472 						  IIO_EV_TYPE_THRESH,
473 						  IIO_EV_DIR_FALLING),
474 			       timestamp);
475 
476 	if (t & LIS3L02DQ_REG_WAKE_UP_SRC_INTERRUPT_Y_HIGH)
477 		iio_push_event(indio_dev,
478 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
479 						  0,
480 						  IIO_MOD_Y,
481 						  IIO_EV_TYPE_THRESH,
482 						  IIO_EV_DIR_RISING),
483 			       timestamp);
484 
485 	if (t & LIS3L02DQ_REG_WAKE_UP_SRC_INTERRUPT_Y_LOW)
486 		iio_push_event(indio_dev,
487 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
488 						  0,
489 						  IIO_MOD_Y,
490 						  IIO_EV_TYPE_THRESH,
491 						  IIO_EV_DIR_FALLING),
492 			       timestamp);
493 
494 	if (t & LIS3L02DQ_REG_WAKE_UP_SRC_INTERRUPT_X_HIGH)
495 		iio_push_event(indio_dev,
496 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
497 						  0,
498 						  IIO_MOD_X,
499 						  IIO_EV_TYPE_THRESH,
500 						  IIO_EV_DIR_RISING),
501 			       timestamp);
502 
503 	if (t & LIS3L02DQ_REG_WAKE_UP_SRC_INTERRUPT_X_LOW)
504 		iio_push_event(indio_dev,
505 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
506 						  0,
507 						  IIO_MOD_X,
508 						  IIO_EV_TYPE_THRESH,
509 						  IIO_EV_DIR_FALLING),
510 			       timestamp);
511 
512 	/* Ack and allow for new interrupts */
513 	lis3l02dq_spi_read_reg_8(indio_dev,
514 				 LIS3L02DQ_REG_WAKE_UP_ACK_ADDR,
515 				 &t);
516 
517 	return IRQ_HANDLED;
518 }
519 
520 static const struct iio_event_spec lis3l02dq_event[] = {
521 	{
522 		.type = IIO_EV_TYPE_THRESH,
523 		.dir = IIO_EV_DIR_RISING,
524 		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
525 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
526 	}, {
527 		.type = IIO_EV_TYPE_THRESH,
528 		.dir = IIO_EV_DIR_FALLING,
529 		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
530 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
531 	}
532 };
533 
534 #define LIS3L02DQ_CHAN(index, mod)				\
535 	{							\
536 		.type = IIO_ACCEL,				\
537 		.modified = 1,					\
538 		.channel2 = mod,				\
539 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
540 			BIT(IIO_CHAN_INFO_CALIBSCALE) |		\
541 			BIT(IIO_CHAN_INFO_CALIBBIAS),		\
542 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
543 		.address = index,				\
544 		.scan_index = index,				\
545 		.scan_type = {					\
546 			.sign = 's',				\
547 			.realbits = 12,				\
548 			.storagebits = 16,			\
549 		},						\
550 		.event_spec = lis3l02dq_event,			\
551 		.num_event_specs = ARRAY_SIZE(lis3l02dq_event),	\
552 	 }
553 
554 static const struct iio_chan_spec lis3l02dq_channels[] = {
555 	LIS3L02DQ_CHAN(0, IIO_MOD_X),
556 	LIS3L02DQ_CHAN(1, IIO_MOD_Y),
557 	LIS3L02DQ_CHAN(2, IIO_MOD_Z),
558 	IIO_CHAN_SOFT_TIMESTAMP(3)
559 };
560 
lis3l02dq_read_event_config(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir)561 static int lis3l02dq_read_event_config(struct iio_dev *indio_dev,
562 				       const struct iio_chan_spec *chan,
563 				       enum iio_event_type type,
564 				       enum iio_event_direction dir)
565 {
566 	u8 val;
567 	int ret;
568 	u8 mask = (1 << (chan->channel2*2 + (dir == IIO_EV_DIR_RISING)));
569 
570 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
571 				       LIS3L02DQ_REG_WAKE_UP_CFG_ADDR,
572 				       &val);
573 	if (ret < 0)
574 		return ret;
575 
576 	return !!(val & mask);
577 }
578 
lis3l02dq_disable_all_events(struct iio_dev * indio_dev)579 int lis3l02dq_disable_all_events(struct iio_dev *indio_dev)
580 {
581 	int ret;
582 	u8 control, val;
583 
584 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
585 				       LIS3L02DQ_REG_CTRL_2_ADDR,
586 				       &control);
587 
588 	control &= ~LIS3L02DQ_REG_CTRL_2_ENABLE_INTERRUPT;
589 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
590 					LIS3L02DQ_REG_CTRL_2_ADDR,
591 					control);
592 	if (ret)
593 		goto error_ret;
594 	/* Also for consistency clear the mask */
595 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
596 				       LIS3L02DQ_REG_WAKE_UP_CFG_ADDR,
597 				       &val);
598 	if (ret)
599 		goto error_ret;
600 	val &= ~0x3f;
601 
602 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
603 					LIS3L02DQ_REG_WAKE_UP_CFG_ADDR,
604 					val);
605 	if (ret)
606 		goto error_ret;
607 
608 	ret = control;
609 error_ret:
610 	return ret;
611 }
612 
lis3l02dq_write_event_config(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,int state)613 static int lis3l02dq_write_event_config(struct iio_dev *indio_dev,
614 					const struct iio_chan_spec *chan,
615 					enum iio_event_type type,
616 					enum iio_event_direction dir,
617 					int state)
618 {
619 	int ret = 0;
620 	u8 val, control;
621 	u8 currentlyset;
622 	bool changed = false;
623 	u8 mask = (1 << (chan->channel2*2 + (dir == IIO_EV_DIR_RISING)));
624 
625 	mutex_lock(&indio_dev->mlock);
626 	/* read current control */
627 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
628 				       LIS3L02DQ_REG_CTRL_2_ADDR,
629 				       &control);
630 	if (ret)
631 		goto error_ret;
632 	ret = lis3l02dq_spi_read_reg_8(indio_dev,
633 				       LIS3L02DQ_REG_WAKE_UP_CFG_ADDR,
634 				       &val);
635 	if (ret < 0)
636 		goto error_ret;
637 	currentlyset = val & mask;
638 
639 	if (!currentlyset && state) {
640 		changed = true;
641 		val |= mask;
642 	} else if (currentlyset && !state) {
643 		changed = true;
644 		val &= ~mask;
645 	}
646 
647 	if (changed) {
648 		ret = lis3l02dq_spi_write_reg_8(indio_dev,
649 						LIS3L02DQ_REG_WAKE_UP_CFG_ADDR,
650 						val);
651 		if (ret)
652 			goto error_ret;
653 		control = val & 0x3f ?
654 			(control | LIS3L02DQ_REG_CTRL_2_ENABLE_INTERRUPT) :
655 			(control & ~LIS3L02DQ_REG_CTRL_2_ENABLE_INTERRUPT);
656 		ret = lis3l02dq_spi_write_reg_8(indio_dev,
657 						LIS3L02DQ_REG_CTRL_2_ADDR,
658 						control);
659 		if (ret)
660 			goto error_ret;
661 	}
662 
663 error_ret:
664 	mutex_unlock(&indio_dev->mlock);
665 	return ret;
666 }
667 
668 static struct attribute *lis3l02dq_attributes[] = {
669 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
670 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
671 	NULL
672 };
673 
674 static const struct attribute_group lis3l02dq_attribute_group = {
675 	.attrs = lis3l02dq_attributes,
676 };
677 
678 static const struct iio_info lis3l02dq_info = {
679 	.read_raw = &lis3l02dq_read_raw,
680 	.write_raw = &lis3l02dq_write_raw,
681 	.read_event_value = &lis3l02dq_read_thresh,
682 	.write_event_value = &lis3l02dq_write_thresh,
683 	.write_event_config = &lis3l02dq_write_event_config,
684 	.read_event_config = &lis3l02dq_read_event_config,
685 	.driver_module = THIS_MODULE,
686 	.attrs = &lis3l02dq_attribute_group,
687 };
688 
lis3l02dq_probe(struct spi_device * spi)689 static int lis3l02dq_probe(struct spi_device *spi)
690 {
691 	int ret;
692 	struct lis3l02dq_state *st;
693 	struct iio_dev *indio_dev;
694 
695 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
696 	if (!indio_dev)
697 		return -ENOMEM;
698 	st = iio_priv(indio_dev);
699 	/* this is only used for removal purposes */
700 	spi_set_drvdata(spi, indio_dev);
701 
702 	st->us = spi;
703 	st->gpio = of_get_gpio(spi->dev.of_node, 0);
704 	mutex_init(&st->buf_lock);
705 	indio_dev->name = spi->dev.driver->name;
706 	indio_dev->dev.parent = &spi->dev;
707 	indio_dev->info = &lis3l02dq_info;
708 	indio_dev->channels = lis3l02dq_channels;
709 	indio_dev->num_channels = ARRAY_SIZE(lis3l02dq_channels);
710 
711 	indio_dev->modes = INDIO_DIRECT_MODE;
712 
713 	ret = lis3l02dq_configure_buffer(indio_dev);
714 	if (ret)
715 		return ret;
716 
717 	if (spi->irq) {
718 		ret = request_threaded_irq(st->us->irq,
719 					   &lis3l02dq_th,
720 					   &lis3l02dq_event_handler,
721 					   IRQF_TRIGGER_RISING,
722 					   "lis3l02dq",
723 					   indio_dev);
724 		if (ret)
725 			goto error_unreg_buffer_funcs;
726 
727 		ret = lis3l02dq_probe_trigger(indio_dev);
728 		if (ret)
729 			goto error_free_interrupt;
730 	}
731 
732 	/* Get the device into a sane initial state */
733 	ret = lis3l02dq_initial_setup(indio_dev);
734 	if (ret)
735 		goto error_remove_trigger;
736 
737 	ret = iio_device_register(indio_dev);
738 	if (ret)
739 		goto error_remove_trigger;
740 
741 	return 0;
742 
743 error_remove_trigger:
744 	if (spi->irq)
745 		lis3l02dq_remove_trigger(indio_dev);
746 error_free_interrupt:
747 	if (spi->irq)
748 		free_irq(st->us->irq, indio_dev);
749 error_unreg_buffer_funcs:
750 	lis3l02dq_unconfigure_buffer(indio_dev);
751 	return ret;
752 }
753 
754 /* Power down the device */
lis3l02dq_stop_device(struct iio_dev * indio_dev)755 static int lis3l02dq_stop_device(struct iio_dev *indio_dev)
756 {
757 	int ret;
758 	struct lis3l02dq_state *st = iio_priv(indio_dev);
759 	u8 val = 0;
760 
761 	mutex_lock(&indio_dev->mlock);
762 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
763 					LIS3L02DQ_REG_CTRL_1_ADDR,
764 					val);
765 	if (ret) {
766 		dev_err(&st->us->dev, "problem with turning device off: ctrl1");
767 		goto err_ret;
768 	}
769 
770 	ret = lis3l02dq_spi_write_reg_8(indio_dev,
771 					LIS3L02DQ_REG_CTRL_2_ADDR,
772 					val);
773 	if (ret)
774 		dev_err(&st->us->dev, "problem with turning device off: ctrl2");
775 err_ret:
776 	mutex_unlock(&indio_dev->mlock);
777 	return ret;
778 }
779 
780 /* fixme, confirm ordering in this function */
lis3l02dq_remove(struct spi_device * spi)781 static int lis3l02dq_remove(struct spi_device *spi)
782 {
783 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
784 	struct lis3l02dq_state *st = iio_priv(indio_dev);
785 
786 	iio_device_unregister(indio_dev);
787 
788 	lis3l02dq_disable_all_events(indio_dev);
789 	lis3l02dq_stop_device(indio_dev);
790 
791 	if (spi->irq)
792 		free_irq(st->us->irq, indio_dev);
793 
794 	lis3l02dq_remove_trigger(indio_dev);
795 	lis3l02dq_unconfigure_buffer(indio_dev);
796 
797 	return 0;
798 }
799 
800 static struct spi_driver lis3l02dq_driver = {
801 	.driver = {
802 		.name = "lis3l02dq",
803 		.owner = THIS_MODULE,
804 	},
805 	.probe = lis3l02dq_probe,
806 	.remove = lis3l02dq_remove,
807 };
808 module_spi_driver(lis3l02dq_driver);
809 
810 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
811 MODULE_DESCRIPTION("ST LIS3L02DQ Accelerometer SPI driver");
812 MODULE_LICENSE("GPL v2");
813 MODULE_ALIAS("spi:lis3l02dq");
814