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/types.h>
19 #include <linux/module.h>
20 #include <linux/regmap.h>
21 #include <linux/bitops.h>
22 #include <linux/delay.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/iio/iio.h>
26 #include <linux/iio/sysfs.h>
27 #include <linux/iio/buffer.h>
28 #include <linux/iio/triggered_buffer.h>
29 #include <linux/iio/trigger_consumer.h>
30
31 #include "kxsd9.h"
32
33 #define KXSD9_REG_X 0x00
34 #define KXSD9_REG_Y 0x02
35 #define KXSD9_REG_Z 0x04
36 #define KXSD9_REG_AUX 0x06
37 #define KXSD9_REG_RESET 0x0a
38 #define KXSD9_REG_CTRL_C 0x0c
39
40 #define KXSD9_CTRL_C_FS_MASK 0x03
41 #define KXSD9_CTRL_C_FS_8G 0x00
42 #define KXSD9_CTRL_C_FS_6G 0x01
43 #define KXSD9_CTRL_C_FS_4G 0x02
44 #define KXSD9_CTRL_C_FS_2G 0x03
45 #define KXSD9_CTRL_C_MOT_LAT BIT(3)
46 #define KXSD9_CTRL_C_MOT_LEV BIT(4)
47 #define KXSD9_CTRL_C_LP_MASK 0xe0
48 #define KXSD9_CTRL_C_LP_NONE 0x00
49 #define KXSD9_CTRL_C_LP_2000HZC BIT(5)
50 #define KXSD9_CTRL_C_LP_2000HZB BIT(6)
51 #define KXSD9_CTRL_C_LP_2000HZA (BIT(5)|BIT(6))
52 #define KXSD9_CTRL_C_LP_1000HZ BIT(7)
53 #define KXSD9_CTRL_C_LP_500HZ (BIT(7)|BIT(5))
54 #define KXSD9_CTRL_C_LP_100HZ (BIT(7)|BIT(6))
55 #define KXSD9_CTRL_C_LP_50HZ (BIT(7)|BIT(6)|BIT(5))
56
57 #define KXSD9_REG_CTRL_B 0x0d
58
59 #define KXSD9_CTRL_B_CLK_HLD BIT(7)
60 #define KXSD9_CTRL_B_ENABLE BIT(6)
61 #define KXSD9_CTRL_B_ST BIT(5) /* Self-test */
62
63 #define KXSD9_REG_CTRL_A 0x0e
64
65 /**
66 * struct kxsd9_state - device related storage
67 * @dev: pointer to the parent device
68 * @map: regmap to the device
69 * @orientation: mounting matrix, flipped axis etc
70 * @regs: regulators for this device, VDD and IOVDD
71 * @scale: the current scaling setting
72 */
73 struct kxsd9_state {
74 struct device *dev;
75 struct regmap *map;
76 struct iio_mount_matrix orientation;
77 struct regulator_bulk_data regs[2];
78 u8 scale;
79 };
80
81 #define KXSD9_SCALE_2G "0.011978"
82 #define KXSD9_SCALE_4G "0.023927"
83 #define KXSD9_SCALE_6G "0.035934"
84 #define KXSD9_SCALE_8G "0.047853"
85
86 /* reverse order */
87 static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 };
88
89 #define KXSD9_ZERO_G_OFFSET -2048
90
91 /*
92 * Regulator names
93 */
94 static const char kxsd9_reg_vdd[] = "vdd";
95 static const char kxsd9_reg_iovdd[] = "iovdd";
96
kxsd9_write_scale(struct iio_dev * indio_dev,int micro)97 static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro)
98 {
99 int ret, i;
100 struct kxsd9_state *st = iio_priv(indio_dev);
101 bool foundit = false;
102
103 for (i = 0; i < 4; i++)
104 if (micro == kxsd9_micro_scales[i]) {
105 foundit = true;
106 break;
107 }
108 if (!foundit)
109 return -EINVAL;
110
111 ret = regmap_update_bits(st->map,
112 KXSD9_REG_CTRL_C,
113 KXSD9_CTRL_C_FS_MASK,
114 i);
115 if (ret < 0)
116 goto error_ret;
117
118 /* Cached scale when the sensor is powered down */
119 st->scale = i;
120
121 error_ret:
122 return ret;
123 }
124
125 static IIO_CONST_ATTR(accel_scale_available,
126 KXSD9_SCALE_2G " "
127 KXSD9_SCALE_4G " "
128 KXSD9_SCALE_6G " "
129 KXSD9_SCALE_8G);
130
131 static struct attribute *kxsd9_attributes[] = {
132 &iio_const_attr_accel_scale_available.dev_attr.attr,
133 NULL,
134 };
135
kxsd9_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)136 static int kxsd9_write_raw(struct iio_dev *indio_dev,
137 struct iio_chan_spec const *chan,
138 int val,
139 int val2,
140 long mask)
141 {
142 int ret = -EINVAL;
143 struct kxsd9_state *st = iio_priv(indio_dev);
144
145 pm_runtime_get_sync(st->dev);
146
147 if (mask == IIO_CHAN_INFO_SCALE) {
148 /* Check no integer component */
149 if (val)
150 ret = -EINVAL;
151 else
152 ret = kxsd9_write_scale(indio_dev, val2);
153 }
154
155 pm_runtime_put_autosuspend(st->dev);
156
157 return ret;
158 }
159
kxsd9_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)160 static int kxsd9_read_raw(struct iio_dev *indio_dev,
161 struct iio_chan_spec const *chan,
162 int *val, int *val2, long mask)
163 {
164 int ret = -EINVAL;
165 struct kxsd9_state *st = iio_priv(indio_dev);
166 unsigned int regval;
167 __be16 raw_val;
168 u16 nval;
169
170 pm_runtime_get_sync(st->dev);
171
172 switch (mask) {
173 case IIO_CHAN_INFO_RAW:
174 ret = regmap_bulk_read(st->map, chan->address, &raw_val,
175 sizeof(raw_val));
176 if (ret)
177 goto error_ret;
178 nval = be16_to_cpu(raw_val);
179 /* Only 12 bits are valid */
180 nval >>= 4;
181 *val = nval;
182 ret = IIO_VAL_INT;
183 break;
184 case IIO_CHAN_INFO_OFFSET:
185 /* This has a bias of -2048 */
186 *val = KXSD9_ZERO_G_OFFSET;
187 ret = IIO_VAL_INT;
188 break;
189 case IIO_CHAN_INFO_SCALE:
190 ret = regmap_read(st->map,
191 KXSD9_REG_CTRL_C,
192 ®val);
193 if (ret < 0)
194 goto error_ret;
195 *val = 0;
196 *val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK];
197 ret = IIO_VAL_INT_PLUS_MICRO;
198 break;
199 }
200
201 error_ret:
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 aligned_s64 ts;
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_ts(indio_dev, &hw_values, sizeof(hw_values),
232 iio_get_time_ns(indio_dev));
233 out:
234 iio_trigger_notify_done(indio_dev->trig);
235
236 return IRQ_HANDLED;
237 }
238
kxsd9_buffer_preenable(struct iio_dev * indio_dev)239 static int kxsd9_buffer_preenable(struct iio_dev *indio_dev)
240 {
241 struct kxsd9_state *st = iio_priv(indio_dev);
242
243 pm_runtime_get_sync(st->dev);
244
245 return 0;
246 }
247
kxsd9_buffer_postdisable(struct iio_dev * indio_dev)248 static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev)
249 {
250 struct kxsd9_state *st = iio_priv(indio_dev);
251
252 pm_runtime_put_autosuspend(st->dev);
253
254 return 0;
255 }
256
257 static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = {
258 .preenable = kxsd9_buffer_preenable,
259 .postdisable = kxsd9_buffer_postdisable,
260 };
261
262 static const struct iio_mount_matrix *
kxsd9_get_mount_matrix(const struct iio_dev * indio_dev,const struct iio_chan_spec * chan)263 kxsd9_get_mount_matrix(const struct iio_dev *indio_dev,
264 const struct iio_chan_spec *chan)
265 {
266 struct kxsd9_state *st = iio_priv(indio_dev);
267
268 return &st->orientation;
269 }
270
271 static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = {
272 IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix),
273 { }
274 };
275
276 #define KXSD9_ACCEL_CHAN(axis, index) \
277 { \
278 .type = IIO_ACCEL, \
279 .modified = 1, \
280 .channel2 = IIO_MOD_##axis, \
281 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
282 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
283 BIT(IIO_CHAN_INFO_OFFSET), \
284 .ext_info = kxsd9_ext_info, \
285 .address = KXSD9_REG_##axis, \
286 .scan_index = index, \
287 .scan_type = { \
288 .sign = 'u', \
289 .realbits = 12, \
290 .storagebits = 16, \
291 .shift = 4, \
292 .endianness = IIO_BE, \
293 }, \
294 }
295
296 static const struct iio_chan_spec kxsd9_channels[] = {
297 KXSD9_ACCEL_CHAN(X, 0),
298 KXSD9_ACCEL_CHAN(Y, 1),
299 KXSD9_ACCEL_CHAN(Z, 2),
300 {
301 .type = IIO_VOLTAGE,
302 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
303 .indexed = 1,
304 .address = KXSD9_REG_AUX,
305 .scan_index = 3,
306 .scan_type = {
307 .sign = 'u',
308 .realbits = 12,
309 .storagebits = 16,
310 .shift = 4,
311 .endianness = IIO_BE,
312 },
313 },
314 IIO_CHAN_SOFT_TIMESTAMP(4),
315 };
316
317 static const struct attribute_group kxsd9_attribute_group = {
318 .attrs = kxsd9_attributes,
319 };
320
kxsd9_power_up(struct kxsd9_state * st)321 static int kxsd9_power_up(struct kxsd9_state *st)
322 {
323 int ret;
324
325 /* Enable the regulators */
326 ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs);
327 if (ret) {
328 dev_err(st->dev, "Cannot enable regulators\n");
329 return ret;
330 }
331
332 /* Power up */
333 ret = regmap_write(st->map,
334 KXSD9_REG_CTRL_B,
335 KXSD9_CTRL_B_ENABLE);
336 if (ret)
337 return ret;
338
339 /*
340 * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g,
341 * latched wakeup
342 */
343 ret = regmap_write(st->map,
344 KXSD9_REG_CTRL_C,
345 KXSD9_CTRL_C_LP_1000HZ |
346 KXSD9_CTRL_C_MOT_LEV |
347 KXSD9_CTRL_C_MOT_LAT |
348 st->scale);
349 if (ret)
350 return ret;
351
352 /*
353 * Power-up time depends on the LPF setting, but typ 15.9 ms, let's
354 * set 20 ms to allow for some slack.
355 */
356 msleep(20);
357
358 return 0;
359 };
360
kxsd9_power_down(struct kxsd9_state * st)361 static int kxsd9_power_down(struct kxsd9_state *st)
362 {
363 int ret;
364
365 /*
366 * Set into low power mode - since there may be more users of the
367 * regulators this is the first step of the power saving: it will
368 * make sure we conserve power even if there are others users on the
369 * regulators.
370 */
371 ret = regmap_clear_bits(st->map, KXSD9_REG_CTRL_B, KXSD9_CTRL_B_ENABLE);
372 if (ret)
373 return ret;
374
375 /* Disable the regulators */
376 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs);
377 if (ret) {
378 dev_err(st->dev, "Cannot disable regulators\n");
379 return ret;
380 }
381
382 return 0;
383 }
384
385 static const struct iio_info kxsd9_info = {
386 .read_raw = &kxsd9_read_raw,
387 .write_raw = &kxsd9_write_raw,
388 .attrs = &kxsd9_attribute_group,
389 };
390
391 /* Four channels apart from timestamp, scan mask = 0x0f */
392 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 };
393
kxsd9_common_probe(struct device * dev,struct regmap * map,const char * name)394 int kxsd9_common_probe(struct device *dev,
395 struct regmap *map,
396 const char *name)
397 {
398 struct iio_dev *indio_dev;
399 struct kxsd9_state *st;
400 int ret;
401
402 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
403 if (!indio_dev)
404 return -ENOMEM;
405
406 st = iio_priv(indio_dev);
407 st->dev = dev;
408 st->map = map;
409
410 indio_dev->channels = kxsd9_channels;
411 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels);
412 indio_dev->name = name;
413 indio_dev->info = &kxsd9_info;
414 indio_dev->modes = INDIO_DIRECT_MODE;
415 indio_dev->available_scan_masks = kxsd9_scan_masks;
416
417 /* Read the mounting matrix, if present */
418 ret = iio_read_mount_matrix(dev, &st->orientation);
419 if (ret)
420 return ret;
421
422 /* Fetch and turn on regulators */
423 st->regs[0].supply = kxsd9_reg_vdd;
424 st->regs[1].supply = kxsd9_reg_iovdd;
425 ret = devm_regulator_bulk_get(dev,
426 ARRAY_SIZE(st->regs),
427 st->regs);
428 if (ret) {
429 dev_err(dev, "Cannot get regulators\n");
430 return ret;
431 }
432 /* Default scaling */
433 st->scale = KXSD9_CTRL_C_FS_2G;
434
435 kxsd9_power_up(st);
436
437 ret = iio_triggered_buffer_setup(indio_dev,
438 iio_pollfunc_store_time,
439 kxsd9_trigger_handler,
440 &kxsd9_buffer_setup_ops);
441 if (ret) {
442 dev_err(dev, "triggered buffer setup failed\n");
443 goto err_power_down;
444 }
445
446 ret = iio_device_register(indio_dev);
447 if (ret)
448 goto err_cleanup_buffer;
449
450 dev_set_drvdata(dev, indio_dev);
451
452 /* Enable runtime PM */
453 pm_runtime_get_noresume(dev);
454 pm_runtime_set_active(dev);
455 pm_runtime_enable(dev);
456 /*
457 * Set autosuspend to two orders of magnitude larger than the
458 * start-up time. 20ms start-up time means 2000ms autosuspend,
459 * i.e. 2 seconds.
460 */
461 pm_runtime_set_autosuspend_delay(dev, 2000);
462 pm_runtime_use_autosuspend(dev);
463 pm_runtime_put(dev);
464
465 return 0;
466
467 err_cleanup_buffer:
468 iio_triggered_buffer_cleanup(indio_dev);
469 err_power_down:
470 kxsd9_power_down(st);
471
472 return ret;
473 }
474 EXPORT_SYMBOL_NS(kxsd9_common_probe, "IIO_KXSD9");
475
kxsd9_common_remove(struct device * dev)476 void kxsd9_common_remove(struct device *dev)
477 {
478 struct iio_dev *indio_dev = dev_get_drvdata(dev);
479 struct kxsd9_state *st = iio_priv(indio_dev);
480
481 iio_triggered_buffer_cleanup(indio_dev);
482 iio_device_unregister(indio_dev);
483 pm_runtime_get_sync(dev);
484 pm_runtime_put_noidle(dev);
485 pm_runtime_disable(dev);
486 kxsd9_power_down(st);
487 }
488 EXPORT_SYMBOL_NS(kxsd9_common_remove, "IIO_KXSD9");
489
kxsd9_runtime_suspend(struct device * dev)490 static int kxsd9_runtime_suspend(struct device *dev)
491 {
492 struct iio_dev *indio_dev = dev_get_drvdata(dev);
493 struct kxsd9_state *st = iio_priv(indio_dev);
494
495 return kxsd9_power_down(st);
496 }
497
kxsd9_runtime_resume(struct device * dev)498 static int kxsd9_runtime_resume(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_up(st);
504 }
505
506 EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend,
507 kxsd9_runtime_resume, NULL, IIO_KXSD9);
508
509 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
510 MODULE_DESCRIPTION("Kionix KXSD9 driver");
511 MODULE_LICENSE("GPL v2");
512