1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * kxsd9.c simple support for the Kionix KXSD9 3D
4 * accelerometer.
5 *
6 * Copyright (c) 2008-2009 Jonathan Cameron <jic23@kernel.org>
7 *
8 * The i2c interface is very similar, so shouldn't be a problem once
9 * I have a suitable wire made up.
10 *
11 * TODO: Support the motion detector
12 */
13
14 #include <linux/device.h>
15 #include <linux/kernel.h>
16 #include <linux/sysfs.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <linux/regmap.h>
20 #include <linux/bitops.h>
21 #include <linux/delay.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/iio/iio.h>
25 #include <linux/iio/sysfs.h>
26 #include <linux/iio/buffer.h>
27 #include <linux/iio/triggered_buffer.h>
28 #include <linux/iio/trigger_consumer.h>
29
30 #include "kxsd9.h"
31
32 #define KXSD9_REG_X 0x00
33 #define KXSD9_REG_Y 0x02
34 #define KXSD9_REG_Z 0x04
35 #define KXSD9_REG_AUX 0x06
36 #define KXSD9_REG_RESET 0x0a
37 #define KXSD9_REG_CTRL_C 0x0c
38
39 #define KXSD9_CTRL_C_FS_MASK 0x03
40 #define KXSD9_CTRL_C_FS_8G 0x00
41 #define KXSD9_CTRL_C_FS_6G 0x01
42 #define KXSD9_CTRL_C_FS_4G 0x02
43 #define KXSD9_CTRL_C_FS_2G 0x03
44 #define KXSD9_CTRL_C_MOT_LAT BIT(3)
45 #define KXSD9_CTRL_C_MOT_LEV BIT(4)
46 #define KXSD9_CTRL_C_LP_MASK 0xe0
47 #define KXSD9_CTRL_C_LP_NONE 0x00
48 #define KXSD9_CTRL_C_LP_2000HZC BIT(5)
49 #define KXSD9_CTRL_C_LP_2000HZB BIT(6)
50 #define KXSD9_CTRL_C_LP_2000HZA (BIT(5)|BIT(6))
51 #define KXSD9_CTRL_C_LP_1000HZ BIT(7)
52 #define KXSD9_CTRL_C_LP_500HZ (BIT(7)|BIT(5))
53 #define KXSD9_CTRL_C_LP_100HZ (BIT(7)|BIT(6))
54 #define KXSD9_CTRL_C_LP_50HZ (BIT(7)|BIT(6)|BIT(5))
55
56 #define KXSD9_REG_CTRL_B 0x0d
57
58 #define KXSD9_CTRL_B_CLK_HLD BIT(7)
59 #define KXSD9_CTRL_B_ENABLE BIT(6)
60 #define KXSD9_CTRL_B_ST BIT(5) /* Self-test */
61
62 #define KXSD9_REG_CTRL_A 0x0e
63
64 /**
65 * struct kxsd9_state - device related storage
66 * @dev: pointer to the parent device
67 * @map: regmap to the device
68 * @orientation: mounting matrix, flipped axis etc
69 * @regs: regulators for this device, VDD and IOVDD
70 * @scale: the current scaling setting
71 */
72 struct kxsd9_state {
73 struct device *dev;
74 struct regmap *map;
75 struct iio_mount_matrix orientation;
76 struct regulator_bulk_data regs[2];
77 u8 scale;
78 };
79
80 #define KXSD9_SCALE_2G "0.011978"
81 #define KXSD9_SCALE_4G "0.023927"
82 #define KXSD9_SCALE_6G "0.035934"
83 #define KXSD9_SCALE_8G "0.047853"
84
85 /* reverse order */
86 static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 };
87
88 #define KXSD9_ZERO_G_OFFSET -2048
89
90 /*
91 * Regulator names
92 */
93 static const char kxsd9_reg_vdd[] = "vdd";
94 static const char kxsd9_reg_iovdd[] = "iovdd";
95
kxsd9_write_scale(struct iio_dev * indio_dev,int micro)96 static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro)
97 {
98 int ret, i;
99 struct kxsd9_state *st = iio_priv(indio_dev);
100 bool foundit = false;
101
102 for (i = 0; i < 4; i++)
103 if (micro == kxsd9_micro_scales[i]) {
104 foundit = true;
105 break;
106 }
107 if (!foundit)
108 return -EINVAL;
109
110 ret = regmap_update_bits(st->map,
111 KXSD9_REG_CTRL_C,
112 KXSD9_CTRL_C_FS_MASK,
113 i);
114 if (ret < 0)
115 goto error_ret;
116
117 /* Cached scale when the sensor is powered down */
118 st->scale = i;
119
120 error_ret:
121 return ret;
122 }
123
124 static IIO_CONST_ATTR(accel_scale_available,
125 KXSD9_SCALE_2G " "
126 KXSD9_SCALE_4G " "
127 KXSD9_SCALE_6G " "
128 KXSD9_SCALE_8G);
129
130 static struct attribute *kxsd9_attributes[] = {
131 &iio_const_attr_accel_scale_available.dev_attr.attr,
132 NULL,
133 };
134
kxsd9_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)135 static int kxsd9_write_raw(struct iio_dev *indio_dev,
136 struct iio_chan_spec const *chan,
137 int val,
138 int val2,
139 long mask)
140 {
141 int ret = -EINVAL;
142 struct kxsd9_state *st = iio_priv(indio_dev);
143
144 pm_runtime_get_sync(st->dev);
145
146 if (mask == IIO_CHAN_INFO_SCALE) {
147 /* Check no integer component */
148 if (val)
149 return -EINVAL;
150 ret = kxsd9_write_scale(indio_dev, val2);
151 }
152
153 pm_runtime_mark_last_busy(st->dev);
154 pm_runtime_put_autosuspend(st->dev);
155
156 return ret;
157 }
158
kxsd9_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)159 static int kxsd9_read_raw(struct iio_dev *indio_dev,
160 struct iio_chan_spec const *chan,
161 int *val, int *val2, long mask)
162 {
163 int ret = -EINVAL;
164 struct kxsd9_state *st = iio_priv(indio_dev);
165 unsigned int regval;
166 __be16 raw_val;
167 u16 nval;
168
169 pm_runtime_get_sync(st->dev);
170
171 switch (mask) {
172 case IIO_CHAN_INFO_RAW:
173 ret = regmap_bulk_read(st->map, chan->address, &raw_val,
174 sizeof(raw_val));
175 if (ret)
176 goto error_ret;
177 nval = be16_to_cpu(raw_val);
178 /* Only 12 bits are valid */
179 nval >>= 4;
180 *val = nval;
181 ret = IIO_VAL_INT;
182 break;
183 case IIO_CHAN_INFO_OFFSET:
184 /* This has a bias of -2048 */
185 *val = KXSD9_ZERO_G_OFFSET;
186 ret = IIO_VAL_INT;
187 break;
188 case IIO_CHAN_INFO_SCALE:
189 ret = regmap_read(st->map,
190 KXSD9_REG_CTRL_C,
191 ®val);
192 if (ret < 0)
193 goto error_ret;
194 *val = 0;
195 *val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK];
196 ret = IIO_VAL_INT_PLUS_MICRO;
197 break;
198 }
199
200 error_ret:
201 pm_runtime_mark_last_busy(st->dev);
202 pm_runtime_put_autosuspend(st->dev);
203
204 return ret;
205 };
206
kxsd9_trigger_handler(int irq,void * p)207 static irqreturn_t kxsd9_trigger_handler(int irq, void *p)
208 {
209 const struct iio_poll_func *pf = p;
210 struct iio_dev *indio_dev = pf->indio_dev;
211 struct kxsd9_state *st = iio_priv(indio_dev);
212 /*
213 * Ensure correct positioning and alignment of timestamp.
214 * No need to zero initialize as all elements written.
215 */
216 struct {
217 __be16 chan[4];
218 s64 ts __aligned(8);
219 } hw_values;
220 int ret;
221
222 ret = regmap_bulk_read(st->map,
223 KXSD9_REG_X,
224 hw_values.chan,
225 sizeof(hw_values.chan));
226 if (ret) {
227 dev_err(st->dev, "error reading data: %d\n", ret);
228 goto out;
229 }
230
231 iio_push_to_buffers_with_timestamp(indio_dev,
232 &hw_values,
233 iio_get_time_ns(indio_dev));
234 out:
235 iio_trigger_notify_done(indio_dev->trig);
236
237 return IRQ_HANDLED;
238 }
239
kxsd9_buffer_preenable(struct iio_dev * indio_dev)240 static int kxsd9_buffer_preenable(struct iio_dev *indio_dev)
241 {
242 struct kxsd9_state *st = iio_priv(indio_dev);
243
244 pm_runtime_get_sync(st->dev);
245
246 return 0;
247 }
248
kxsd9_buffer_postdisable(struct iio_dev * indio_dev)249 static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev)
250 {
251 struct kxsd9_state *st = iio_priv(indio_dev);
252
253 pm_runtime_mark_last_busy(st->dev);
254 pm_runtime_put_autosuspend(st->dev);
255
256 return 0;
257 }
258
259 static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = {
260 .preenable = kxsd9_buffer_preenable,
261 .postdisable = kxsd9_buffer_postdisable,
262 };
263
264 static const struct iio_mount_matrix *
kxsd9_get_mount_matrix(const struct iio_dev * indio_dev,const struct iio_chan_spec * chan)265 kxsd9_get_mount_matrix(const struct iio_dev *indio_dev,
266 const struct iio_chan_spec *chan)
267 {
268 struct kxsd9_state *st = iio_priv(indio_dev);
269
270 return &st->orientation;
271 }
272
273 static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = {
274 IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix),
275 { },
276 };
277
278 #define KXSD9_ACCEL_CHAN(axis, index) \
279 { \
280 .type = IIO_ACCEL, \
281 .modified = 1, \
282 .channel2 = IIO_MOD_##axis, \
283 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
284 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
285 BIT(IIO_CHAN_INFO_OFFSET), \
286 .ext_info = kxsd9_ext_info, \
287 .address = KXSD9_REG_##axis, \
288 .scan_index = index, \
289 .scan_type = { \
290 .sign = 'u', \
291 .realbits = 12, \
292 .storagebits = 16, \
293 .shift = 4, \
294 .endianness = IIO_BE, \
295 }, \
296 }
297
298 static const struct iio_chan_spec kxsd9_channels[] = {
299 KXSD9_ACCEL_CHAN(X, 0),
300 KXSD9_ACCEL_CHAN(Y, 1),
301 KXSD9_ACCEL_CHAN(Z, 2),
302 {
303 .type = IIO_VOLTAGE,
304 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
305 .indexed = 1,
306 .address = KXSD9_REG_AUX,
307 .scan_index = 3,
308 .scan_type = {
309 .sign = 'u',
310 .realbits = 12,
311 .storagebits = 16,
312 .shift = 4,
313 .endianness = IIO_BE,
314 },
315 },
316 IIO_CHAN_SOFT_TIMESTAMP(4),
317 };
318
319 static const struct attribute_group kxsd9_attribute_group = {
320 .attrs = kxsd9_attributes,
321 };
322
kxsd9_power_up(struct kxsd9_state * st)323 static int kxsd9_power_up(struct kxsd9_state *st)
324 {
325 int ret;
326
327 /* Enable the regulators */
328 ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs);
329 if (ret) {
330 dev_err(st->dev, "Cannot enable regulators\n");
331 return ret;
332 }
333
334 /* Power up */
335 ret = regmap_write(st->map,
336 KXSD9_REG_CTRL_B,
337 KXSD9_CTRL_B_ENABLE);
338 if (ret)
339 return ret;
340
341 /*
342 * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g,
343 * latched wakeup
344 */
345 ret = regmap_write(st->map,
346 KXSD9_REG_CTRL_C,
347 KXSD9_CTRL_C_LP_1000HZ |
348 KXSD9_CTRL_C_MOT_LEV |
349 KXSD9_CTRL_C_MOT_LAT |
350 st->scale);
351 if (ret)
352 return ret;
353
354 /*
355 * Power-up time depends on the LPF setting, but typ 15.9 ms, let's
356 * set 20 ms to allow for some slack.
357 */
358 msleep(20);
359
360 return 0;
361 };
362
kxsd9_power_down(struct kxsd9_state * st)363 static int kxsd9_power_down(struct kxsd9_state *st)
364 {
365 int ret;
366
367 /*
368 * Set into low power mode - since there may be more users of the
369 * regulators this is the first step of the power saving: it will
370 * make sure we conserve power even if there are others users on the
371 * regulators.
372 */
373 ret = regmap_update_bits(st->map,
374 KXSD9_REG_CTRL_B,
375 KXSD9_CTRL_B_ENABLE,
376 0);
377 if (ret)
378 return ret;
379
380 /* Disable the regulators */
381 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs);
382 if (ret) {
383 dev_err(st->dev, "Cannot disable regulators\n");
384 return ret;
385 }
386
387 return 0;
388 }
389
390 static const struct iio_info kxsd9_info = {
391 .read_raw = &kxsd9_read_raw,
392 .write_raw = &kxsd9_write_raw,
393 .attrs = &kxsd9_attribute_group,
394 };
395
396 /* Four channels apart from timestamp, scan mask = 0x0f */
397 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 };
398
kxsd9_common_probe(struct device * dev,struct regmap * map,const char * name)399 int kxsd9_common_probe(struct device *dev,
400 struct regmap *map,
401 const char *name)
402 {
403 struct iio_dev *indio_dev;
404 struct kxsd9_state *st;
405 int ret;
406
407 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
408 if (!indio_dev)
409 return -ENOMEM;
410
411 st = iio_priv(indio_dev);
412 st->dev = dev;
413 st->map = map;
414
415 indio_dev->channels = kxsd9_channels;
416 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels);
417 indio_dev->name = name;
418 indio_dev->info = &kxsd9_info;
419 indio_dev->modes = INDIO_DIRECT_MODE;
420 indio_dev->available_scan_masks = kxsd9_scan_masks;
421
422 /* Read the mounting matrix, if present */
423 ret = iio_read_mount_matrix(dev, "mount-matrix", &st->orientation);
424 if (ret)
425 return ret;
426
427 /* Fetch and turn on regulators */
428 st->regs[0].supply = kxsd9_reg_vdd;
429 st->regs[1].supply = kxsd9_reg_iovdd;
430 ret = devm_regulator_bulk_get(dev,
431 ARRAY_SIZE(st->regs),
432 st->regs);
433 if (ret) {
434 dev_err(dev, "Cannot get regulators\n");
435 return ret;
436 }
437 /* Default scaling */
438 st->scale = KXSD9_CTRL_C_FS_2G;
439
440 kxsd9_power_up(st);
441
442 ret = iio_triggered_buffer_setup(indio_dev,
443 iio_pollfunc_store_time,
444 kxsd9_trigger_handler,
445 &kxsd9_buffer_setup_ops);
446 if (ret) {
447 dev_err(dev, "triggered buffer setup failed\n");
448 goto err_power_down;
449 }
450
451 ret = iio_device_register(indio_dev);
452 if (ret)
453 goto err_cleanup_buffer;
454
455 dev_set_drvdata(dev, indio_dev);
456
457 /* Enable runtime PM */
458 pm_runtime_get_noresume(dev);
459 pm_runtime_set_active(dev);
460 pm_runtime_enable(dev);
461 /*
462 * Set autosuspend to two orders of magnitude larger than the
463 * start-up time. 20ms start-up time means 2000ms autosuspend,
464 * i.e. 2 seconds.
465 */
466 pm_runtime_set_autosuspend_delay(dev, 2000);
467 pm_runtime_use_autosuspend(dev);
468 pm_runtime_put(dev);
469
470 return 0;
471
472 err_cleanup_buffer:
473 iio_triggered_buffer_cleanup(indio_dev);
474 err_power_down:
475 kxsd9_power_down(st);
476
477 return ret;
478 }
479 EXPORT_SYMBOL(kxsd9_common_probe);
480
kxsd9_common_remove(struct device * dev)481 int kxsd9_common_remove(struct device *dev)
482 {
483 struct iio_dev *indio_dev = dev_get_drvdata(dev);
484 struct kxsd9_state *st = iio_priv(indio_dev);
485
486 iio_triggered_buffer_cleanup(indio_dev);
487 iio_device_unregister(indio_dev);
488 pm_runtime_get_sync(dev);
489 pm_runtime_put_noidle(dev);
490 pm_runtime_disable(dev);
491 kxsd9_power_down(st);
492
493 return 0;
494 }
495 EXPORT_SYMBOL(kxsd9_common_remove);
496
497 #ifdef CONFIG_PM
kxsd9_runtime_suspend(struct device * dev)498 static int kxsd9_runtime_suspend(struct device *dev)
499 {
500 struct iio_dev *indio_dev = dev_get_drvdata(dev);
501 struct kxsd9_state *st = iio_priv(indio_dev);
502
503 return kxsd9_power_down(st);
504 }
505
kxsd9_runtime_resume(struct device * dev)506 static int kxsd9_runtime_resume(struct device *dev)
507 {
508 struct iio_dev *indio_dev = dev_get_drvdata(dev);
509 struct kxsd9_state *st = iio_priv(indio_dev);
510
511 return kxsd9_power_up(st);
512 }
513 #endif /* CONFIG_PM */
514
515 const struct dev_pm_ops kxsd9_dev_pm_ops = {
516 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
517 pm_runtime_force_resume)
518 SET_RUNTIME_PM_OPS(kxsd9_runtime_suspend,
519 kxsd9_runtime_resume, NULL)
520 };
521 EXPORT_SYMBOL(kxsd9_dev_pm_ops);
522
523 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
524 MODULE_DESCRIPTION("Kionix KXSD9 driver");
525 MODULE_LICENSE("GPL v2");
526