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Merge tag 'for-linus-20190706' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / iio / accel / sca3000.c
blob274ce2f8bddfcae5a5e9ff3292a8d80c68d400b3
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * sca3000_core.c -- support VTI sca3000 series accelerometers via SPI
4 *
5 * Copyright (c) 2009 Jonathan Cameron <jic23@kernel.org>
6 *
7 * See industrialio/accels/sca3000.h for comments.
8 */
9
10 #include <linux/interrupt.h>
11 #include <linux/fs.h>
12 #include <linux/device.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/spi/spi.h>
16 #include <linux/sysfs.h>
17 #include <linux/module.h>
18 #include <linux/uaccess.h>
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/iio/events.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/kfifo_buf.h>
24
25 #define SCA3000_WRITE_REG(a) (((a) << 2) | 0x02)
26 #define SCA3000_READ_REG(a) ((a) << 2)
27
28 #define SCA3000_REG_REVID_ADDR 0x00
29 #define SCA3000_REG_REVID_MAJOR_MASK GENMASK(8, 4)
30 #define SCA3000_REG_REVID_MINOR_MASK GENMASK(3, 0)
31
32 #define SCA3000_REG_STATUS_ADDR 0x02
33 #define SCA3000_LOCKED BIT(5)
34 #define SCA3000_EEPROM_CS_ERROR BIT(1)
35 #define SCA3000_SPI_FRAME_ERROR BIT(0)
36
37 /* All reads done using register decrement so no need to directly access LSBs */
38 #define SCA3000_REG_X_MSB_ADDR 0x05
39 #define SCA3000_REG_Y_MSB_ADDR 0x07
40 #define SCA3000_REG_Z_MSB_ADDR 0x09
41
42 #define SCA3000_REG_RING_OUT_ADDR 0x0f
43
44 /* Temp read untested - the e05 doesn't have the sensor */
45 #define SCA3000_REG_TEMP_MSB_ADDR 0x13
46
47 #define SCA3000_REG_MODE_ADDR 0x14
48 #define SCA3000_MODE_PROT_MASK 0x28
49 #define SCA3000_REG_MODE_RING_BUF_ENABLE BIT(7)
50 #define SCA3000_REG_MODE_RING_BUF_8BIT BIT(6)
51
52 /*
53 * Free fall detection triggers an interrupt if the acceleration
54 * is below a threshold for equivalent of 25cm drop
55 */
56 #define SCA3000_REG_MODE_FREE_FALL_DETECT BIT(4)
57 #define SCA3000_REG_MODE_MEAS_MODE_NORMAL 0x00
58 #define SCA3000_REG_MODE_MEAS_MODE_OP_1 0x01
59 #define SCA3000_REG_MODE_MEAS_MODE_OP_2 0x02
60
61 /*
62 * In motion detection mode the accelerations are band pass filtered
63 * (approx 1 - 25Hz) and then a programmable threshold used to trigger
64 * and interrupt.
65 */
66 #define SCA3000_REG_MODE_MEAS_MODE_MOT_DET 0x03
67 #define SCA3000_REG_MODE_MODE_MASK 0x03
68
69 #define SCA3000_REG_BUF_COUNT_ADDR 0x15
70
71 #define SCA3000_REG_INT_STATUS_ADDR 0x16
72 #define SCA3000_REG_INT_STATUS_THREE_QUARTERS BIT(7)
73 #define SCA3000_REG_INT_STATUS_HALF BIT(6)
74
75 #define SCA3000_INT_STATUS_FREE_FALL BIT(3)
76 #define SCA3000_INT_STATUS_Y_TRIGGER BIT(2)
77 #define SCA3000_INT_STATUS_X_TRIGGER BIT(1)
78 #define SCA3000_INT_STATUS_Z_TRIGGER BIT(0)
79
80 /* Used to allow access to multiplexed registers */
81 #define SCA3000_REG_CTRL_SEL_ADDR 0x18
82 /* Only available for SCA3000-D03 and SCA3000-D01 */
83 #define SCA3000_REG_CTRL_SEL_I2C_DISABLE 0x01
84 #define SCA3000_REG_CTRL_SEL_MD_CTRL 0x02
85 #define SCA3000_REG_CTRL_SEL_MD_Y_TH 0x03
86 #define SCA3000_REG_CTRL_SEL_MD_X_TH 0x04
87 #define SCA3000_REG_CTRL_SEL_MD_Z_TH 0x05
88 /*
89 * BE VERY CAREFUL WITH THIS, IF 3 BITS ARE NOT SET the device
90 * will not function
91 */
92 #define SCA3000_REG_CTRL_SEL_OUT_CTRL 0x0B
93
94 #define SCA3000_REG_OUT_CTRL_PROT_MASK 0xE0
95 #define SCA3000_REG_OUT_CTRL_BUF_X_EN 0x10
96 #define SCA3000_REG_OUT_CTRL_BUF_Y_EN 0x08
97 #define SCA3000_REG_OUT_CTRL_BUF_Z_EN 0x04
98 #define SCA3000_REG_OUT_CTRL_BUF_DIV_MASK 0x03
99 #define SCA3000_REG_OUT_CTRL_BUF_DIV_4 0x02
100 #define SCA3000_REG_OUT_CTRL_BUF_DIV_2 0x01
101
102
103 /*
104 * Control which motion detector interrupts are on.
105 * For now only OR combinations are supported.
106 */
107 #define SCA3000_MD_CTRL_PROT_MASK 0xC0
108 #define SCA3000_MD_CTRL_OR_Y BIT(0)
109 #define SCA3000_MD_CTRL_OR_X BIT(1)
110 #define SCA3000_MD_CTRL_OR_Z BIT(2)
111 /* Currently unsupported */
112 #define SCA3000_MD_CTRL_AND_Y BIT(3)
113 #define SCA3000_MD_CTRL_AND_X BIT(4)
114 #define SAC3000_MD_CTRL_AND_Z BIT(5)
115
116 /*
117 * Some control registers of complex access methods requiring this register to
118 * be used to remove a lock.
119 */
120 #define SCA3000_REG_UNLOCK_ADDR 0x1e
121
122 #define SCA3000_REG_INT_MASK_ADDR 0x21
123 #define SCA3000_REG_INT_MASK_PROT_MASK 0x1C
124
125 #define SCA3000_REG_INT_MASK_RING_THREE_QUARTER BIT(7)
126 #define SCA3000_REG_INT_MASK_RING_HALF BIT(6)
127
128 #define SCA3000_REG_INT_MASK_ALL_INTS 0x02
129 #define SCA3000_REG_INT_MASK_ACTIVE_HIGH 0x01
130 #define SCA3000_REG_INT_MASK_ACTIVE_LOW 0x00
131 /* Values of multiplexed registers (write to ctrl_data after select) */
132 #define SCA3000_REG_CTRL_DATA_ADDR 0x22
133
134 /*
135 * Measurement modes available on some sca3000 series chips. Code assumes others
136 * may become available in the future.
137 *
138 * Bypass - Bypass the low-pass filter in the signal channel so as to increase
139 * signal bandwidth.
140 *
141 * Narrow - Narrow low-pass filtering of the signal channel and half output
142 * data rate by decimation.
143 *
144 * Wide - Widen low-pass filtering of signal channel to increase bandwidth
145 */
146 #define SCA3000_OP_MODE_BYPASS 0x01
147 #define SCA3000_OP_MODE_NARROW 0x02
148 #define SCA3000_OP_MODE_WIDE 0x04
149 #define SCA3000_MAX_TX 6
150 #define SCA3000_MAX_RX 2
151
152 /**
153 * struct sca3000_state - device instance state information
154 * @us: the associated spi device
155 * @info: chip variant information
156 * @last_timestamp: the timestamp of the last event
157 * @mo_det_use_count: reference counter for the motion detection unit
158 * @lock: lock used to protect elements of sca3000_state
159 * and the underlying device state.
160 * @tx: dma-able transmit buffer
161 * @rx: dma-able receive buffer
162 **/
163 struct sca3000_state {
164 struct spi_device *us;
165 const struct sca3000_chip_info *info;
166 s64 last_timestamp;
167 int mo_det_use_count;
168 struct mutex lock;
169 /* Can these share a cacheline ? */
170 u8 rx[384] ____cacheline_aligned;
171 u8 tx[6] ____cacheline_aligned;
172 };
173
174 /**
175 * struct sca3000_chip_info - model dependent parameters
176 * @scale: scale * 10^-6
177 * @temp_output: some devices have temperature sensors.
178 * @measurement_mode_freq: normal mode sampling frequency
179 * @measurement_mode_3db_freq: 3db cutoff frequency of the low pass filter for
180 * the normal measurement mode.
181 * @option_mode_1: first optional mode. Not all models have one
182 * @option_mode_1_freq: option mode 1 sampling frequency
183 * @option_mode_1_3db_freq: 3db cutoff frequency of the low pass filter for
184 * the first option mode.
185 * @option_mode_2: second optional mode. Not all chips have one
186 * @option_mode_2_freq: option mode 2 sampling frequency
187 * @option_mode_2_3db_freq: 3db cutoff frequency of the low pass filter for
188 * the second option mode.
189 * @mod_det_mult_xz: Bit wise multipliers to calculate the threshold
190 * for motion detection in the x and z axis.
191 * @mod_det_mult_y: Bit wise multipliers to calculate the threshold
192 * for motion detection in the y axis.
193 *
194 * This structure is used to hold information about the functionality of a given
195 * sca3000 variant.
196 **/
197 struct sca3000_chip_info {
198 unsigned int scale;
199 bool temp_output;
200 int measurement_mode_freq;
201 int measurement_mode_3db_freq;
202 int option_mode_1;
203 int option_mode_1_freq;
204 int option_mode_1_3db_freq;
205 int option_mode_2;
206 int option_mode_2_freq;
207 int option_mode_2_3db_freq;
208 int mot_det_mult_xz[6];
209 int mot_det_mult_y[7];
210 };
211
212 enum sca3000_variant {
213 d01,
214 e02,
215 e04,
216 e05,
217 };
218
219 /*
220 * Note where option modes are not defined, the chip simply does not
221 * support any.
222 * Other chips in the sca3000 series use i2c and are not included here.
223 *
224 * Some of these devices are only listed in the family data sheet and
225 * do not actually appear to be available.
226 */
227 static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = {
228 [d01] = {
229 .scale = 7357,
230 .temp_output = true,
231 .measurement_mode_freq = 250,
232 .measurement_mode_3db_freq = 45,
233 .option_mode_1 = SCA3000_OP_MODE_BYPASS,
234 .option_mode_1_freq = 250,
235 .option_mode_1_3db_freq = 70,
236 .mot_det_mult_xz = {50, 100, 200, 350, 650, 1300},
237 .mot_det_mult_y = {50, 100, 150, 250, 450, 850, 1750},
238 },
239 [e02] = {
240 .scale = 9810,
241 .measurement_mode_freq = 125,
242 .measurement_mode_3db_freq = 40,
243 .option_mode_1 = SCA3000_OP_MODE_NARROW,
244 .option_mode_1_freq = 63,
245 .option_mode_1_3db_freq = 11,
246 .mot_det_mult_xz = {100, 150, 300, 550, 1050, 2050},
247 .mot_det_mult_y = {50, 100, 200, 350, 700, 1350, 2700},
248 },
249 [e04] = {
250 .scale = 19620,
251 .measurement_mode_freq = 100,
252 .measurement_mode_3db_freq = 38,
253 .option_mode_1 = SCA3000_OP_MODE_NARROW,
254 .option_mode_1_freq = 50,
255 .option_mode_1_3db_freq = 9,
256 .option_mode_2 = SCA3000_OP_MODE_WIDE,
257 .option_mode_2_freq = 400,
258 .option_mode_2_3db_freq = 70,
259 .mot_det_mult_xz = {200, 300, 600, 1100, 2100, 4100},
260 .mot_det_mult_y = {100, 200, 400, 7000, 1400, 2700, 54000},
261 },
262 [e05] = {
263 .scale = 61313,
264 .measurement_mode_freq = 200,
265 .measurement_mode_3db_freq = 60,
266 .option_mode_1 = SCA3000_OP_MODE_NARROW,
267 .option_mode_1_freq = 50,
268 .option_mode_1_3db_freq = 9,
269 .option_mode_2 = SCA3000_OP_MODE_WIDE,
270 .option_mode_2_freq = 400,
271 .option_mode_2_3db_freq = 75,
272 .mot_det_mult_xz = {600, 900, 1700, 3200, 6100, 11900},
273 .mot_det_mult_y = {300, 600, 1200, 2000, 4100, 7800, 15600},
274 },
275 };
276
277 static int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val)
278 {
279 st->tx[0] = SCA3000_WRITE_REG(address);
280 st->tx[1] = val;
281 return spi_write(st->us, st->tx, 2);
282 }
283
284 static int sca3000_read_data_short(struct sca3000_state *st,
285 u8 reg_address_high,
286 int len)
287 {
288 struct spi_transfer xfer[2] = {
289 {
290 .len = 1,
291 .tx_buf = st->tx,
292 }, {
293 .len = len,
294 .rx_buf = st->rx,
295 }
296 };
297 st->tx[0] = SCA3000_READ_REG(reg_address_high);
298
299 return spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
300 }
301
302 /**
303 * sca3000_reg_lock_on() - test if the ctrl register lock is on
304 * @st: Driver specific device instance data.
305 *
306 * Lock must be held.
307 **/
308 static int sca3000_reg_lock_on(struct sca3000_state *st)
309 {
310 int ret;
311
312 ret = sca3000_read_data_short(st, SCA3000_REG_STATUS_ADDR, 1);
313 if (ret < 0)
314 return ret;
315
316 return !(st->rx[0] & SCA3000_LOCKED);
317 }
318
319 /**
320 * __sca3000_unlock_reg_lock() - unlock the control registers
321 * @st: Driver specific device instance data.
322 *
323 * Note the device does not appear to support doing this in a single transfer.
324 * This should only ever be used as part of ctrl reg read.
325 * Lock must be held before calling this
326 */
327 static int __sca3000_unlock_reg_lock(struct sca3000_state *st)
328 {
329 struct spi_transfer xfer[3] = {
330 {
331 .len = 2,
332 .cs_change = 1,
333 .tx_buf = st->tx,
334 }, {
335 .len = 2,
336 .cs_change = 1,
337 .tx_buf = st->tx + 2,
338 }, {
339 .len = 2,
340 .tx_buf = st->tx + 4,
341 },
342 };
343 st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_UNLOCK_ADDR);
344 st->tx[1] = 0x00;
345 st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_UNLOCK_ADDR);
346 st->tx[3] = 0x50;
347 st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_UNLOCK_ADDR);
348 st->tx[5] = 0xA0;
349
350 return spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
351 }
352
353 /**
354 * sca3000_write_ctrl_reg() write to a lock protect ctrl register
355 * @st: Driver specific device instance data.
356 * @sel: selects which registers we wish to write to
357 * @val: the value to be written
358 *
359 * Certain control registers are protected against overwriting by the lock
360 * register and use a shared write address. This function allows writing of
361 * these registers.
362 * Lock must be held.
363 */
364 static int sca3000_write_ctrl_reg(struct sca3000_state *st,
365 u8 sel,
366 uint8_t val)
367 {
368 int ret;
369
370 ret = sca3000_reg_lock_on(st);
371 if (ret < 0)
372 goto error_ret;
373 if (ret) {
374 ret = __sca3000_unlock_reg_lock(st);
375 if (ret)
376 goto error_ret;
377 }
378
379 /* Set the control select register */
380 ret = sca3000_write_reg(st, SCA3000_REG_CTRL_SEL_ADDR, sel);
381 if (ret)
382 goto error_ret;
383
384 /* Write the actual value into the register */
385 ret = sca3000_write_reg(st, SCA3000_REG_CTRL_DATA_ADDR, val);
386
387 error_ret:
388 return ret;
389 }
390
391 /**
392 * sca3000_read_ctrl_reg() read from lock protected control register.
393 * @st: Driver specific device instance data.
394 * @ctrl_reg: Which ctrl register do we want to read.
395 *
396 * Lock must be held.
397 */
398 static int sca3000_read_ctrl_reg(struct sca3000_state *st,
399 u8 ctrl_reg)
400 {
401 int ret;
402
403 ret = sca3000_reg_lock_on(st);
404 if (ret < 0)
405 goto error_ret;
406 if (ret) {
407 ret = __sca3000_unlock_reg_lock(st);
408 if (ret)
409 goto error_ret;
410 }
411 /* Set the control select register */
412 ret = sca3000_write_reg(st, SCA3000_REG_CTRL_SEL_ADDR, ctrl_reg);
413 if (ret)
414 goto error_ret;
415 ret = sca3000_read_data_short(st, SCA3000_REG_CTRL_DATA_ADDR, 1);
416 if (ret)
417 goto error_ret;
418 return st->rx[0];
419 error_ret:
420 return ret;
421 }
422
423 /**
424 * sca3000_show_rev() - sysfs interface to read the chip revision number
425 * @indio_dev: Device instance specific generic IIO data.
426 * Driver specific device instance data can be obtained via
427 * via iio_priv(indio_dev)
428 */
429 static int sca3000_print_rev(struct iio_dev *indio_dev)
430 {
431 int ret;
432 struct sca3000_state *st = iio_priv(indio_dev);
433
434 mutex_lock(&st->lock);
435 ret = sca3000_read_data_short(st, SCA3000_REG_REVID_ADDR, 1);
436 if (ret < 0)
437 goto error_ret;
438 dev_info(&indio_dev->dev,
439 "sca3000 revision major=%lu, minor=%lu\n",
440 st->rx[0] & SCA3000_REG_REVID_MAJOR_MASK,
441 st->rx[0] & SCA3000_REG_REVID_MINOR_MASK);
442 error_ret:
443 mutex_unlock(&st->lock);
444
445 return ret;
446 }
447
448 static ssize_t
449 sca3000_show_available_3db_freqs(struct device *dev,
450 struct device_attribute *attr,
451 char *buf)
452 {
453 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
454 struct sca3000_state *st = iio_priv(indio_dev);
455 int len;
456
457 len = sprintf(buf, "%d", st->info->measurement_mode_3db_freq);
458 if (st->info->option_mode_1)
459 len += sprintf(buf + len, " %d",
460 st->info->option_mode_1_3db_freq);
461 if (st->info->option_mode_2)
462 len += sprintf(buf + len, " %d",
463 st->info->option_mode_2_3db_freq);
464 len += sprintf(buf + len, "\n");
465
466 return len;
467 }
468
469 static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available,
470 S_IRUGO, sca3000_show_available_3db_freqs,
471 NULL, 0);
472
473 static const struct iio_event_spec sca3000_event = {
474 .type = IIO_EV_TYPE_MAG,
475 .dir = IIO_EV_DIR_RISING,
476 .mask_separate = BIT(IIO_EV_INFO_VALUE) | BIT(IIO_EV_INFO_ENABLE),
477 };
478
479 /*
480 * Note the hack in the number of bits to pretend we have 2 more than
481 * we do in the fifo.
482 */
483 #define SCA3000_CHAN(index, mod) \
484 { \
485 .type = IIO_ACCEL, \
486 .modified = 1, \
487 .channel2 = mod, \
488 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
489 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |\
490 BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),\
491 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
492 .address = index, \
493 .scan_index = index, \
494 .scan_type = { \
495 .sign = 's', \
496 .realbits = 13, \
497 .storagebits = 16, \
498 .shift = 3, \
499 .endianness = IIO_BE, \
500 }, \
501 .event_spec = &sca3000_event, \
502 .num_event_specs = 1, \
503 }
504
505 static const struct iio_event_spec sca3000_freefall_event_spec = {
506 .type = IIO_EV_TYPE_MAG,
507 .dir = IIO_EV_DIR_FALLING,
508 .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
509 BIT(IIO_EV_INFO_PERIOD),
510 };
511
512 static const struct iio_chan_spec sca3000_channels[] = {
513 SCA3000_CHAN(0, IIO_MOD_X),
514 SCA3000_CHAN(1, IIO_MOD_Y),
515 SCA3000_CHAN(2, IIO_MOD_Z),
516 {
517 .type = IIO_ACCEL,
518 .modified = 1,
519 .channel2 = IIO_MOD_X_AND_Y_AND_Z,
520 .scan_index = -1, /* Fake channel */
521 .event_spec = &sca3000_freefall_event_spec,
522 .num_event_specs = 1,
523 },
524 };
525
526 static const struct iio_chan_spec sca3000_channels_with_temp[] = {
527 SCA3000_CHAN(0, IIO_MOD_X),
528 SCA3000_CHAN(1, IIO_MOD_Y),
529 SCA3000_CHAN(2, IIO_MOD_Z),
530 {
531 .type = IIO_TEMP,
532 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
533 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
534 BIT(IIO_CHAN_INFO_OFFSET),
535 /* No buffer support */
536 .scan_index = -1,
537 },
538 {
539 .type = IIO_ACCEL,
540 .modified = 1,
541 .channel2 = IIO_MOD_X_AND_Y_AND_Z,
542 .scan_index = -1, /* Fake channel */
543 .event_spec = &sca3000_freefall_event_spec,
544 .num_event_specs = 1,
545 },
546 };
547
548 static u8 sca3000_addresses[3][3] = {
549 [0] = {SCA3000_REG_X_MSB_ADDR, SCA3000_REG_CTRL_SEL_MD_X_TH,
550 SCA3000_MD_CTRL_OR_X},
551 [1] = {SCA3000_REG_Y_MSB_ADDR, SCA3000_REG_CTRL_SEL_MD_Y_TH,
552 SCA3000_MD_CTRL_OR_Y},
553 [2] = {SCA3000_REG_Z_MSB_ADDR, SCA3000_REG_CTRL_SEL_MD_Z_TH,
554 SCA3000_MD_CTRL_OR_Z},
555 };
556
557 /**
558 * __sca3000_get_base_freq() - obtain mode specific base frequency
559 * @st: Private driver specific device instance specific state.
560 * @info: chip type specific information.
561 * @base_freq: Base frequency for the current measurement mode.
562 *
563 * lock must be held
564 */
565 static inline int __sca3000_get_base_freq(struct sca3000_state *st,
566 const struct sca3000_chip_info *info,
567 int *base_freq)
568 {
569 int ret;
570
571 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
572 if (ret)
573 goto error_ret;
574 switch (SCA3000_REG_MODE_MODE_MASK & st->rx[0]) {
575 case SCA3000_REG_MODE_MEAS_MODE_NORMAL:
576 *base_freq = info->measurement_mode_freq;
577 break;
578 case SCA3000_REG_MODE_MEAS_MODE_OP_1:
579 *base_freq = info->option_mode_1_freq;
580 break;
581 case SCA3000_REG_MODE_MEAS_MODE_OP_2:
582 *base_freq = info->option_mode_2_freq;
583 break;
584 default:
585 ret = -EINVAL;
586 }
587 error_ret:
588 return ret;
589 }
590
591 /**
592 * sca3000_read_raw_samp_freq() - read_raw handler for IIO_CHAN_INFO_SAMP_FREQ
593 * @st: Private driver specific device instance specific state.
594 * @val: The frequency read back.
595 *
596 * lock must be held
597 **/
598 static int sca3000_read_raw_samp_freq(struct sca3000_state *st, int *val)
599 {
600 int ret;
601
602 ret = __sca3000_get_base_freq(st, st->info, val);
603 if (ret)
604 return ret;
605
606 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
607 if (ret < 0)
608 return ret;
609
610 if (*val > 0) {
611 ret &= SCA3000_REG_OUT_CTRL_BUF_DIV_MASK;
612 switch (ret) {
613 case SCA3000_REG_OUT_CTRL_BUF_DIV_2:
614 *val /= 2;
615 break;
616 case SCA3000_REG_OUT_CTRL_BUF_DIV_4:
617 *val /= 4;
618 break;
619 }
620 }
621
622 return 0;
623 }
624
625 /**
626 * sca3000_write_raw_samp_freq() - write_raw handler for IIO_CHAN_INFO_SAMP_FREQ
627 * @st: Private driver specific device instance specific state.
628 * @val: The frequency desired.
629 *
630 * lock must be held
631 */
632 static int sca3000_write_raw_samp_freq(struct sca3000_state *st, int val)
633 {
634 int ret, base_freq, ctrlval;
635
636 ret = __sca3000_get_base_freq(st, st->info, &base_freq);
637 if (ret)
638 return ret;
639
640 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
641 if (ret < 0)
642 return ret;
643
644 ctrlval = ret & ~SCA3000_REG_OUT_CTRL_BUF_DIV_MASK;
645
646 if (val == base_freq / 2)
647 ctrlval |= SCA3000_REG_OUT_CTRL_BUF_DIV_2;
648 if (val == base_freq / 4)
649 ctrlval |= SCA3000_REG_OUT_CTRL_BUF_DIV_4;
650 else if (val != base_freq)
651 return -EINVAL;
652
653 return sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
654 ctrlval);
655 }
656
657 static int sca3000_read_3db_freq(struct sca3000_state *st, int *val)
658 {
659 int ret;
660
661 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
662 if (ret)
663 return ret;
664
665 /* mask bottom 2 bits - only ones that are relevant */
666 st->rx[0] &= SCA3000_REG_MODE_MODE_MASK;
667 switch (st->rx[0]) {
668 case SCA3000_REG_MODE_MEAS_MODE_NORMAL:
669 *val = st->info->measurement_mode_3db_freq;
670 return IIO_VAL_INT;
671 case SCA3000_REG_MODE_MEAS_MODE_MOT_DET:
672 return -EBUSY;
673 case SCA3000_REG_MODE_MEAS_MODE_OP_1:
674 *val = st->info->option_mode_1_3db_freq;
675 return IIO_VAL_INT;
676 case SCA3000_REG_MODE_MEAS_MODE_OP_2:
677 *val = st->info->option_mode_2_3db_freq;
678 return IIO_VAL_INT;
679 default:
680 return -EINVAL;
681 }
682 }
683
684 static int sca3000_write_3db_freq(struct sca3000_state *st, int val)
685 {
686 int ret;
687 int mode;
688
689 if (val == st->info->measurement_mode_3db_freq)
690 mode = SCA3000_REG_MODE_MEAS_MODE_NORMAL;
691 else if (st->info->option_mode_1 &&
692 (val == st->info->option_mode_1_3db_freq))
693 mode = SCA3000_REG_MODE_MEAS_MODE_OP_1;
694 else if (st->info->option_mode_2 &&
695 (val == st->info->option_mode_2_3db_freq))
696 mode = SCA3000_REG_MODE_MEAS_MODE_OP_2;
697 else
698 return -EINVAL;
699 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
700 if (ret)
701 return ret;
702
703 st->rx[0] &= ~SCA3000_REG_MODE_MODE_MASK;
704 st->rx[0] |= (mode & SCA3000_REG_MODE_MODE_MASK);
705
706 return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR, st->rx[0]);
707 }
708
709 static int sca3000_read_raw(struct iio_dev *indio_dev,
710 struct iio_chan_spec const *chan,
711 int *val,
712 int *val2,
713 long mask)
714 {
715 struct sca3000_state *st = iio_priv(indio_dev);
716 int ret;
717 u8 address;
718
719 switch (mask) {
720 case IIO_CHAN_INFO_RAW:
721 mutex_lock(&st->lock);
722 if (chan->type == IIO_ACCEL) {
723 if (st->mo_det_use_count) {
724 mutex_unlock(&st->lock);
725 return -EBUSY;
726 }
727 address = sca3000_addresses[chan->address][0];
728 ret = sca3000_read_data_short(st, address, 2);
729 if (ret < 0) {
730 mutex_unlock(&st->lock);
731 return ret;
732 }
733 *val = (be16_to_cpup((__be16 *)st->rx) >> 3) & 0x1FFF;
734 *val = ((*val) << (sizeof(*val) * 8 - 13)) >>
735 (sizeof(*val) * 8 - 13);
736 } else {
737 /* get the temperature when available */
738 ret = sca3000_read_data_short(st,
739 SCA3000_REG_TEMP_MSB_ADDR,
740 2);
741 if (ret < 0) {
742 mutex_unlock(&st->lock);
743 return ret;
744 }
745 *val = ((st->rx[0] & 0x3F) << 3) |
746 ((st->rx[1] & 0xE0) >> 5);
747 }
748 mutex_unlock(&st->lock);
749 return IIO_VAL_INT;
750 case IIO_CHAN_INFO_SCALE:
751 *val = 0;
752 if (chan->type == IIO_ACCEL)
753 *val2 = st->info->scale;
754 else /* temperature */
755 *val2 = 555556;
756 return IIO_VAL_INT_PLUS_MICRO;
757 case IIO_CHAN_INFO_OFFSET:
758 *val = -214;
759 *val2 = 600000;
760 return IIO_VAL_INT_PLUS_MICRO;
761 case IIO_CHAN_INFO_SAMP_FREQ:
762 mutex_lock(&st->lock);
763 ret = sca3000_read_raw_samp_freq(st, val);
764 mutex_unlock(&st->lock);
765 return ret ? ret : IIO_VAL_INT;
766 case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
767 mutex_lock(&st->lock);
768 ret = sca3000_read_3db_freq(st, val);
769 mutex_unlock(&st->lock);
770 return ret;
771 default:
772 return -EINVAL;
773 }
774 }
775
776 static int sca3000_write_raw(struct iio_dev *indio_dev,
777 struct iio_chan_spec const *chan,
778 int val, int val2, long mask)
779 {
780 struct sca3000_state *st = iio_priv(indio_dev);
781 int ret;
782
783 switch (mask) {
784 case IIO_CHAN_INFO_SAMP_FREQ:
785 if (val2)
786 return -EINVAL;
787 mutex_lock(&st->lock);
788 ret = sca3000_write_raw_samp_freq(st, val);
789 mutex_unlock(&st->lock);
790 return ret;
791 case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
792 if (val2)
793 return -EINVAL;
794 mutex_lock(&st->lock);
795 ret = sca3000_write_3db_freq(st, val);
796 mutex_unlock(&st->lock);
797 return ret;
798 default:
799 return -EINVAL;
800 }
801
802 return ret;
803 }
804
805 /**
806 * sca3000_read_av_freq() - sysfs function to get available frequencies
807 * @dev: Device structure for this device.
808 * @attr: Description of the attribute.
809 * @buf: Incoming string
810 *
811 * The later modes are only relevant to the ring buffer - and depend on current
812 * mode. Note that data sheet gives rather wide tolerances for these so integer
813 * division will give good enough answer and not all chips have them specified
814 * at all.
815 **/
816 static ssize_t sca3000_read_av_freq(struct device *dev,
817 struct device_attribute *attr,
818 char *buf)
819 {
820 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
821 struct sca3000_state *st = iio_priv(indio_dev);
822 int len = 0, ret, val;
823
824 mutex_lock(&st->lock);
825 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
826 val = st->rx[0];
827 mutex_unlock(&st->lock);
828 if (ret)
829 goto error_ret;
830
831 switch (val & SCA3000_REG_MODE_MODE_MASK) {
832 case SCA3000_REG_MODE_MEAS_MODE_NORMAL:
833 len += sprintf(buf + len, "%d %d %d\n",
834 st->info->measurement_mode_freq,
835 st->info->measurement_mode_freq / 2,
836 st->info->measurement_mode_freq / 4);
837 break;
838 case SCA3000_REG_MODE_MEAS_MODE_OP_1:
839 len += sprintf(buf + len, "%d %d %d\n",
840 st->info->option_mode_1_freq,
841 st->info->option_mode_1_freq / 2,
842 st->info->option_mode_1_freq / 4);
843 break;
844 case SCA3000_REG_MODE_MEAS_MODE_OP_2:
845 len += sprintf(buf + len, "%d %d %d\n",
846 st->info->option_mode_2_freq,
847 st->info->option_mode_2_freq / 2,
848 st->info->option_mode_2_freq / 4);
849 break;
850 }
851 return len;
852 error_ret:
853 return ret;
854 }
855
856 /*
857 * Should only really be registered if ring buffer support is compiled in.
858 * Does no harm however and doing it right would add a fair bit of complexity
859 */
860 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sca3000_read_av_freq);
861
862 /**
863 * sca3000_read_event_value() - query of a threshold or period
864 **/
865 static int sca3000_read_event_value(struct iio_dev *indio_dev,
866 const struct iio_chan_spec *chan,
867 enum iio_event_type type,
868 enum iio_event_direction dir,
869 enum iio_event_info info,
870 int *val, int *val2)
871 {
872 int ret, i;
873 struct sca3000_state *st = iio_priv(indio_dev);
874
875 switch (info) {
876 case IIO_EV_INFO_VALUE:
877 mutex_lock(&st->lock);
878 ret = sca3000_read_ctrl_reg(st,
879 sca3000_addresses[chan->address][1]);
880 mutex_unlock(&st->lock);
881 if (ret < 0)
882 return ret;
883 *val = 0;
884 if (chan->channel2 == IIO_MOD_Y)
885 for_each_set_bit(i, (unsigned long *)&ret,
886 ARRAY_SIZE(st->info->mot_det_mult_y))
887 *val += st->info->mot_det_mult_y[i];
888 else
889 for_each_set_bit(i, (unsigned long *)&ret,
890 ARRAY_SIZE(st->info->mot_det_mult_xz))
891 *val += st->info->mot_det_mult_xz[i];
892
893 return IIO_VAL_INT;
894 case IIO_EV_INFO_PERIOD:
895 *val = 0;
896 *val2 = 226000;
897 return IIO_VAL_INT_PLUS_MICRO;
898 default:
899 return -EINVAL;
900 }
901 }
902
903 /**
904 * sca3000_write_value() - control of threshold and period
905 * @indio_dev: Device instance specific IIO information.
906 * @chan: Description of the channel for which the event is being
907 * configured.
908 * @type: The type of event being configured, here magnitude rising
909 * as everything else is read only.
910 * @dir: Direction of the event (here rising)
911 * @info: What information about the event are we configuring.
912 * Here the threshold only.
913 * @val: Integer part of the value being written..
914 * @val2: Non integer part of the value being written. Here always 0.
915 */
916 static int sca3000_write_event_value(struct iio_dev *indio_dev,
917 const struct iio_chan_spec *chan,
918 enum iio_event_type type,
919 enum iio_event_direction dir,
920 enum iio_event_info info,
921 int val, int val2)
922 {
923 struct sca3000_state *st = iio_priv(indio_dev);
924 int ret;
925 int i;
926 u8 nonlinear = 0;
927
928 if (chan->channel2 == IIO_MOD_Y) {
929 i = ARRAY_SIZE(st->info->mot_det_mult_y);
930 while (i > 0)
931 if (val >= st->info->mot_det_mult_y[--i]) {
932 nonlinear |= (1 << i);
933 val -= st->info->mot_det_mult_y[i];
934 }
935 } else {
936 i = ARRAY_SIZE(st->info->mot_det_mult_xz);
937 while (i > 0)
938 if (val >= st->info->mot_det_mult_xz[--i]) {
939 nonlinear |= (1 << i);
940 val -= st->info->mot_det_mult_xz[i];
941 }
942 }
943
944 mutex_lock(&st->lock);
945 ret = sca3000_write_ctrl_reg(st,
946 sca3000_addresses[chan->address][1],
947 nonlinear);
948 mutex_unlock(&st->lock);
949
950 return ret;
951 }
952
953 static struct attribute *sca3000_attributes[] = {
954 &iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr,
955 &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
956 NULL,
957 };
958
959 static const struct attribute_group sca3000_attribute_group = {
960 .attrs = sca3000_attributes,
961 };
962
963 static int sca3000_read_data(struct sca3000_state *st,
964 u8 reg_address_high,
965 u8 *rx,
966 int len)
967 {
968 int ret;
969 struct spi_transfer xfer[2] = {
970 {
971 .len = 1,
972 .tx_buf = st->tx,
973 }, {
974 .len = len,
975 .rx_buf = rx,
976 }
977 };
978
979 st->tx[0] = SCA3000_READ_REG(reg_address_high);
980 ret = spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
981 if (ret) {
982 dev_err(get_device(&st->us->dev), "problem reading register");
983 return ret;
984 }
985
986 return 0;
987 }
988
989 /**
990 * sca3000_ring_int_process() - ring specific interrupt handling.
991 * @val: Value of the interrupt status register.
992 * @indio_dev: Device instance specific IIO device structure.
993 */
994 static void sca3000_ring_int_process(u8 val, struct iio_dev *indio_dev)
995 {
996 struct sca3000_state *st = iio_priv(indio_dev);
997 int ret, i, num_available;
998
999 mutex_lock(&st->lock);
1000
1001 if (val & SCA3000_REG_INT_STATUS_HALF) {
1002 ret = sca3000_read_data_short(st, SCA3000_REG_BUF_COUNT_ADDR,
1003 1);
1004 if (ret)
1005 goto error_ret;
1006 num_available = st->rx[0];
1007 /*
1008 * num_available is the total number of samples available
1009 * i.e. number of time points * number of channels.
1010 */
1011 ret = sca3000_read_data(st, SCA3000_REG_RING_OUT_ADDR, st->rx,
1012 num_available * 2);
1013 if (ret)
1014 goto error_ret;
1015 for (i = 0; i < num_available / 3; i++) {
1016 /*
1017 * Dirty hack to cover for 11 bit in fifo, 13 bit
1018 * direct reading.
1019 *
1020 * In theory the bottom two bits are undefined.
1021 * In reality they appear to always be 0.
1022 */
1023 iio_push_to_buffers(indio_dev, st->rx + i * 3 * 2);
1024 }
1025 }
1026 error_ret:
1027 mutex_unlock(&st->lock);
1028 }
1029
1030 /**
1031 * sca3000_event_handler() - handling ring and non ring events
1032 * @irq: The irq being handled.
1033 * @private: struct iio_device pointer for the device.
1034 *
1035 * Ring related interrupt handler. Depending on event, push to
1036 * the ring buffer event chrdev or the event one.
1037 *
1038 * This function is complicated by the fact that the devices can signify ring
1039 * and non ring events via the same interrupt line and they can only
1040 * be distinguished via a read of the relevant status register.
1041 */
1042 static irqreturn_t sca3000_event_handler(int irq, void *private)
1043 {
1044 struct iio_dev *indio_dev = private;
1045 struct sca3000_state *st = iio_priv(indio_dev);
1046 int ret, val;
1047 s64 last_timestamp = iio_get_time_ns(indio_dev);
1048
1049 /*
1050 * Could lead if badly timed to an extra read of status reg,
1051 * but ensures no interrupt is missed.
1052 */
1053 mutex_lock(&st->lock);
1054 ret = sca3000_read_data_short(st, SCA3000_REG_INT_STATUS_ADDR, 1);
1055 val = st->rx[0];
1056 mutex_unlock(&st->lock);
1057 if (ret)
1058 goto done;
1059
1060 sca3000_ring_int_process(val, indio_dev);
1061
1062 if (val & SCA3000_INT_STATUS_FREE_FALL)
1063 iio_push_event(indio_dev,
1064 IIO_MOD_EVENT_CODE(IIO_ACCEL,
1065 0,
1066 IIO_MOD_X_AND_Y_AND_Z,
1067 IIO_EV_TYPE_MAG,
1068 IIO_EV_DIR_FALLING),
1069 last_timestamp);
1070
1071 if (val & SCA3000_INT_STATUS_Y_TRIGGER)
1072 iio_push_event(indio_dev,
1073 IIO_MOD_EVENT_CODE(IIO_ACCEL,
1074 0,
1075 IIO_MOD_Y,
1076 IIO_EV_TYPE_MAG,
1077 IIO_EV_DIR_RISING),
1078 last_timestamp);
1079
1080 if (val & SCA3000_INT_STATUS_X_TRIGGER)
1081 iio_push_event(indio_dev,
1082 IIO_MOD_EVENT_CODE(IIO_ACCEL,
1083 0,
1084 IIO_MOD_X,
1085 IIO_EV_TYPE_MAG,
1086 IIO_EV_DIR_RISING),
1087 last_timestamp);
1088
1089 if (val & SCA3000_INT_STATUS_Z_TRIGGER)
1090 iio_push_event(indio_dev,
1091 IIO_MOD_EVENT_CODE(IIO_ACCEL,
1092 0,
1093 IIO_MOD_Z,
1094 IIO_EV_TYPE_MAG,
1095 IIO_EV_DIR_RISING),
1096 last_timestamp);
1097
1098 done:
1099 return IRQ_HANDLED;
1100 }
1101
1102 /**
1103 * sca3000_read_event_config() what events are enabled
1104 **/
1105 static int sca3000_read_event_config(struct iio_dev *indio_dev,
1106 const struct iio_chan_spec *chan,
1107 enum iio_event_type type,
1108 enum iio_event_direction dir)
1109 {
1110 struct sca3000_state *st = iio_priv(indio_dev);
1111 int ret;
1112 /* read current value of mode register */
1113 mutex_lock(&st->lock);
1114
1115 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
1116 if (ret)
1117 goto error_ret;
1118
1119 switch (chan->channel2) {
1120 case IIO_MOD_X_AND_Y_AND_Z:
1121 ret = !!(st->rx[0] & SCA3000_REG_MODE_FREE_FALL_DETECT);
1122 break;
1123 case IIO_MOD_X:
1124 case IIO_MOD_Y:
1125 case IIO_MOD_Z:
1126 /*
1127 * Motion detection mode cannot run at the same time as
1128 * acceleration data being read.
1129 */
1130 if ((st->rx[0] & SCA3000_REG_MODE_MODE_MASK)
1131 != SCA3000_REG_MODE_MEAS_MODE_MOT_DET) {
1132 ret = 0;
1133 } else {
1134 ret = sca3000_read_ctrl_reg(st,
1135 SCA3000_REG_CTRL_SEL_MD_CTRL);
1136 if (ret < 0)
1137 goto error_ret;
1138 /* only supporting logical or's for now */
1139 ret = !!(ret & sca3000_addresses[chan->address][2]);
1140 }
1141 break;
1142 default:
1143 ret = -EINVAL;
1144 }
1145
1146 error_ret:
1147 mutex_unlock(&st->lock);
1148
1149 return ret;
1150 }
1151
1152 static int sca3000_freefall_set_state(struct iio_dev *indio_dev, int state)
1153 {
1154 struct sca3000_state *st = iio_priv(indio_dev);
1155 int ret;
1156
1157 /* read current value of mode register */
1158 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
1159 if (ret)
1160 return ret;
1161
1162 /* if off and should be on */
1163 if (state && !(st->rx[0] & SCA3000_REG_MODE_FREE_FALL_DETECT))
1164 return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR,
1165 st->rx[0] | SCA3000_REG_MODE_FREE_FALL_DETECT);
1166 /* if on and should be off */
1167 else if (!state && (st->rx[0] & SCA3000_REG_MODE_FREE_FALL_DETECT))
1168 return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR,
1169 st->rx[0] & ~SCA3000_REG_MODE_FREE_FALL_DETECT);
1170 else
1171 return 0;
1172 }
1173
1174 static int sca3000_motion_detect_set_state(struct iio_dev *indio_dev, int axis,
1175 int state)
1176 {
1177 struct sca3000_state *st = iio_priv(indio_dev);
1178 int ret, ctrlval;
1179
1180 /*
1181 * First read the motion detector config to find out if
1182 * this axis is on
1183 */
1184 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
1185 if (ret < 0)
1186 return ret;
1187 ctrlval = ret;
1188 /* if off and should be on */
1189 if (state && !(ctrlval & sca3000_addresses[axis][2])) {
1190 ret = sca3000_write_ctrl_reg(st,
1191 SCA3000_REG_CTRL_SEL_MD_CTRL,
1192 ctrlval |
1193 sca3000_addresses[axis][2]);
1194 if (ret)
1195 return ret;
1196 st->mo_det_use_count++;
1197 } else if (!state && (ctrlval & sca3000_addresses[axis][2])) {
1198 ret = sca3000_write_ctrl_reg(st,
1199 SCA3000_REG_CTRL_SEL_MD_CTRL,
1200 ctrlval &
1201 ~(sca3000_addresses[axis][2]));
1202 if (ret)
1203 return ret;
1204 st->mo_det_use_count--;
1205 }
1206
1207 /* read current value of mode register */
1208 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
1209 if (ret)
1210 return ret;
1211 /* if off and should be on */
1212 if ((st->mo_det_use_count) &&
1213 ((st->rx[0] & SCA3000_REG_MODE_MODE_MASK)
1214 != SCA3000_REG_MODE_MEAS_MODE_MOT_DET))
1215 return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR,
1216 (st->rx[0] & ~SCA3000_REG_MODE_MODE_MASK)
1217 | SCA3000_REG_MODE_MEAS_MODE_MOT_DET);
1218 /* if on and should be off */
1219 else if (!(st->mo_det_use_count) &&
1220 ((st->rx[0] & SCA3000_REG_MODE_MODE_MASK)
1221 == SCA3000_REG_MODE_MEAS_MODE_MOT_DET))
1222 return sca3000_write_reg(st, SCA3000_REG_MODE_ADDR,
1223 st->rx[0] & SCA3000_REG_MODE_MODE_MASK);
1224 else
1225 return 0;
1226 }
1227
1228 /**
1229 * sca3000_write_event_config() - simple on off control for motion detector
1230 * @indio_dev: IIO device instance specific structure. Data specific to this
1231 * particular driver may be accessed via iio_priv(indio_dev).
1232 * @chan: Description of the channel whose event we are configuring.
1233 * @type: The type of event.
1234 * @dir: The direction of the event.
1235 * @state: Desired state of event being configured.
1236 *
1237 * This is a per axis control, but enabling any will result in the
1238 * motion detector unit being enabled.
1239 * N.B. enabling motion detector stops normal data acquisition.
1240 * There is a complexity in knowing which mode to return to when
1241 * this mode is disabled. Currently normal mode is assumed.
1242 **/
1243 static int sca3000_write_event_config(struct iio_dev *indio_dev,
1244 const struct iio_chan_spec *chan,
1245 enum iio_event_type type,
1246 enum iio_event_direction dir,
1247 int state)
1248 {
1249 struct sca3000_state *st = iio_priv(indio_dev);
1250 int ret;
1251
1252 mutex_lock(&st->lock);
1253 switch (chan->channel2) {
1254 case IIO_MOD_X_AND_Y_AND_Z:
1255 ret = sca3000_freefall_set_state(indio_dev, state);
1256 break;
1257
1258 case IIO_MOD_X:
1259 case IIO_MOD_Y:
1260 case IIO_MOD_Z:
1261 ret = sca3000_motion_detect_set_state(indio_dev,
1262 chan->address,
1263 state);
1264 break;
1265 default:
1266 ret = -EINVAL;
1267 break;
1268 }
1269 mutex_unlock(&st->lock);
1270
1271 return ret;
1272 }
1273
1274 static int sca3000_configure_ring(struct iio_dev *indio_dev)
1275 {
1276 struct iio_buffer *buffer;
1277
1278 buffer = devm_iio_kfifo_allocate(&indio_dev->dev);
1279 if (!buffer)
1280 return -ENOMEM;
1281
1282 iio_device_attach_buffer(indio_dev, buffer);
1283 indio_dev->modes |= INDIO_BUFFER_SOFTWARE;
1284
1285 return 0;
1286 }
1287
1288 static inline
1289 int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state)
1290 {
1291 struct sca3000_state *st = iio_priv(indio_dev);
1292 int ret;
1293
1294 mutex_lock(&st->lock);
1295 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
1296 if (ret)
1297 goto error_ret;
1298 if (state) {
1299 dev_info(&indio_dev->dev, "supposedly enabling ring buffer\n");
1300 ret = sca3000_write_reg(st,
1301 SCA3000_REG_MODE_ADDR,
1302 (st->rx[0] | SCA3000_REG_MODE_RING_BUF_ENABLE));
1303 } else
1304 ret = sca3000_write_reg(st,
1305 SCA3000_REG_MODE_ADDR,
1306 (st->rx[0] & ~SCA3000_REG_MODE_RING_BUF_ENABLE));
1307 error_ret:
1308 mutex_unlock(&st->lock);
1309
1310 return ret;
1311 }
1312
1313 /**
1314 * sca3000_hw_ring_preenable() - hw ring buffer preenable function
1315 * @indio_dev: structure representing the IIO device. Device instance
1316 * specific state can be accessed via iio_priv(indio_dev).
1317 *
1318 * Very simple enable function as the chip will allows normal reads
1319 * during ring buffer operation so as long as it is indeed running
1320 * before we notify the core, the precise ordering does not matter.
1321 */
1322 static int sca3000_hw_ring_preenable(struct iio_dev *indio_dev)
1323 {
1324 int ret;
1325 struct sca3000_state *st = iio_priv(indio_dev);
1326
1327 mutex_lock(&st->lock);
1328
1329 /* Enable the 50% full interrupt */
1330 ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1);
1331 if (ret)
1332 goto error_unlock;
1333 ret = sca3000_write_reg(st,
1334 SCA3000_REG_INT_MASK_ADDR,
1335 st->rx[0] | SCA3000_REG_INT_MASK_RING_HALF);
1336 if (ret)
1337 goto error_unlock;
1338
1339 mutex_unlock(&st->lock);
1340
1341 return __sca3000_hw_ring_state_set(indio_dev, 1);
1342
1343 error_unlock:
1344 mutex_unlock(&st->lock);
1345
1346 return ret;
1347 }
1348
1349 static int sca3000_hw_ring_postdisable(struct iio_dev *indio_dev)
1350 {
1351 int ret;
1352 struct sca3000_state *st = iio_priv(indio_dev);
1353
1354 ret = __sca3000_hw_ring_state_set(indio_dev, 0);
1355 if (ret)
1356 return ret;
1357
1358 /* Disable the 50% full interrupt */
1359 mutex_lock(&st->lock);
1360
1361 ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1);
1362 if (ret)
1363 goto unlock;
1364 ret = sca3000_write_reg(st,
1365 SCA3000_REG_INT_MASK_ADDR,
1366 st->rx[0] & ~SCA3000_REG_INT_MASK_RING_HALF);
1367 unlock:
1368 mutex_unlock(&st->lock);
1369 return ret;
1370 }
1371
1372 static const struct iio_buffer_setup_ops sca3000_ring_setup_ops = {
1373 .preenable = &sca3000_hw_ring_preenable,
1374 .postdisable = &sca3000_hw_ring_postdisable,
1375 };
1376
1377 /**
1378 * sca3000_clean_setup() - get the device into a predictable state
1379 * @st: Device instance specific private data structure
1380 *
1381 * Devices use flash memory to store many of the register values
1382 * and hence can come up in somewhat unpredictable states.
1383 * Hence reset everything on driver load.
1384 */
1385 static int sca3000_clean_setup(struct sca3000_state *st)
1386 {
1387 int ret;
1388
1389 mutex_lock(&st->lock);
1390 /* Ensure all interrupts have been acknowledged */
1391 ret = sca3000_read_data_short(st, SCA3000_REG_INT_STATUS_ADDR, 1);
1392 if (ret)
1393 goto error_ret;
1394
1395 /* Turn off all motion detection channels */
1396 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
1397 if (ret < 0)
1398 goto error_ret;
1399 ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL,
1400 ret & SCA3000_MD_CTRL_PROT_MASK);
1401 if (ret)
1402 goto error_ret;
1403
1404 /* Disable ring buffer */
1405 ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
1406 if (ret < 0)
1407 goto error_ret;
1408 ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
1409 (ret & SCA3000_REG_OUT_CTRL_PROT_MASK)
1410 | SCA3000_REG_OUT_CTRL_BUF_X_EN
1411 | SCA3000_REG_OUT_CTRL_BUF_Y_EN
1412 | SCA3000_REG_OUT_CTRL_BUF_Z_EN
1413 | SCA3000_REG_OUT_CTRL_BUF_DIV_4);
1414 if (ret)
1415 goto error_ret;
1416 /* Enable interrupts, relevant to mode and set up as active low */
1417 ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1);
1418 if (ret)
1419 goto error_ret;
1420 ret = sca3000_write_reg(st,
1421 SCA3000_REG_INT_MASK_ADDR,
1422 (ret & SCA3000_REG_INT_MASK_PROT_MASK)
1423 | SCA3000_REG_INT_MASK_ACTIVE_LOW);
1424 if (ret)
1425 goto error_ret;
1426 /*
1427 * Select normal measurement mode, free fall off, ring off
1428 * Ring in 12 bit mode - it is fine to overwrite reserved bits 3,5
1429 * as that occurs in one of the example on the datasheet
1430 */
1431 ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
1432 if (ret)
1433 goto error_ret;
1434 ret = sca3000_write_reg(st, SCA3000_REG_MODE_ADDR,
1435 (st->rx[0] & SCA3000_MODE_PROT_MASK));
1436
1437 error_ret:
1438 mutex_unlock(&st->lock);
1439 return ret;
1440 }
1441
1442 static const struct iio_info sca3000_info = {
1443 .attrs = &sca3000_attribute_group,
1444 .read_raw = &sca3000_read_raw,
1445 .write_raw = &sca3000_write_raw,
1446 .read_event_value = &sca3000_read_event_value,
1447 .write_event_value = &sca3000_write_event_value,
1448 .read_event_config = &sca3000_read_event_config,
1449 .write_event_config = &sca3000_write_event_config,
1450 };
1451
1452 static int sca3000_probe(struct spi_device *spi)
1453 {
1454 int ret;
1455 struct sca3000_state *st;
1456 struct iio_dev *indio_dev;
1457
1458 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
1459 if (!indio_dev)
1460 return -ENOMEM;
1461
1462 st = iio_priv(indio_dev);
1463 spi_set_drvdata(spi, indio_dev);
1464 st->us = spi;
1465 mutex_init(&st->lock);
1466 st->info = &sca3000_spi_chip_info_tbl[spi_get_device_id(spi)
1467 ->driver_data];
1468
1469 indio_dev->dev.parent = &spi->dev;
1470 indio_dev->name = spi_get_device_id(spi)->name;
1471 indio_dev->info = &sca3000_info;
1472 if (st->info->temp_output) {
1473 indio_dev->channels = sca3000_channels_with_temp;
1474 indio_dev->num_channels =
1475 ARRAY_SIZE(sca3000_channels_with_temp);
1476 } else {
1477 indio_dev->channels = sca3000_channels;
1478 indio_dev->num_channels = ARRAY_SIZE(sca3000_channels);
1479 }
1480 indio_dev->modes = INDIO_DIRECT_MODE;
1481
1482 ret = sca3000_configure_ring(indio_dev);
1483 if (ret)
1484 return ret;
1485
1486 if (spi->irq) {
1487 ret = request_threaded_irq(spi->irq,
1488 NULL,
1489 &sca3000_event_handler,
1490 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
1491 "sca3000",
1492 indio_dev);
1493 if (ret)
1494 return ret;
1495 }
1496 indio_dev->setup_ops = &sca3000_ring_setup_ops;
1497 ret = sca3000_clean_setup(st);
1498 if (ret)
1499 goto error_free_irq;
1500
1501 ret = sca3000_print_rev(indio_dev);
1502 if (ret)
1503 goto error_free_irq;
1504
1505 return iio_device_register(indio_dev);
1506
1507 error_free_irq:
1508 if (spi->irq)
1509 free_irq(spi->irq, indio_dev);
1510
1511 return ret;
1512 }
1513
1514 static int sca3000_stop_all_interrupts(struct sca3000_state *st)
1515 {
1516 int ret;
1517
1518 mutex_lock(&st->lock);
1519 ret = sca3000_read_data_short(st, SCA3000_REG_INT_MASK_ADDR, 1);
1520 if (ret)
1521 goto error_ret;
1522 ret = sca3000_write_reg(st, SCA3000_REG_INT_MASK_ADDR,
1523 (st->rx[0] &
1524 ~(SCA3000_REG_INT_MASK_RING_THREE_QUARTER |
1525 SCA3000_REG_INT_MASK_RING_HALF |
1526 SCA3000_REG_INT_MASK_ALL_INTS)));
1527 error_ret:
1528 mutex_unlock(&st->lock);
1529 return ret;
1530 }
1531
1532 static int sca3000_remove(struct spi_device *spi)
1533 {
1534 struct iio_dev *indio_dev = spi_get_drvdata(spi);
1535 struct sca3000_state *st = iio_priv(indio_dev);
1536
1537 iio_device_unregister(indio_dev);
1538
1539 /* Must ensure no interrupts can be generated after this! */
1540 sca3000_stop_all_interrupts(st);
1541 if (spi->irq)
1542 free_irq(spi->irq, indio_dev);
1543
1544 return 0;
1545 }
1546
1547 static const struct spi_device_id sca3000_id[] = {
1548 {"sca3000_d01", d01},
1549 {"sca3000_e02", e02},
1550 {"sca3000_e04", e04},
1551 {"sca3000_e05", e05},
1552 {}
1553 };
1554 MODULE_DEVICE_TABLE(spi, sca3000_id);
1555
1556 static struct spi_driver sca3000_driver = {
1557 .driver = {
1558 .name = "sca3000",
1559 },
1560 .probe = sca3000_probe,
1561 .remove = sca3000_remove,
1562 .id_table = sca3000_id,
1563 };
1564 module_spi_driver(sca3000_driver);
1565
1566 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1567 MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver");
1568 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support