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 return -EINVAL;
151 ret = kxsd9_write_scale(indio_dev, val2);
152 }
153
154 pm_runtime_mark_last_busy(st->dev);
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_mark_last_busy(st->dev);
203 pm_runtime_put_autosuspend(st->dev);
204
205 return ret;
206 };
207
kxsd9_trigger_handler(int irq,void * p)208 static irqreturn_t kxsd9_trigger_handler(int irq, void *p)
209 {
210 const struct iio_poll_func *pf = p;
211 struct iio_dev *indio_dev = pf->indio_dev;
212 struct kxsd9_state *st = iio_priv(indio_dev);
213 /*
214 * Ensure correct positioning and alignment of timestamp.
215 * No need to zero initialize as all elements written.
216 */
217 struct {
218 __be16 chan[4];
219 aligned_s64 ts;
220 } hw_values;
221 int ret;
222
223 ret = regmap_bulk_read(st->map,
224 KXSD9_REG_X,
225 hw_values.chan,
226 sizeof(hw_values.chan));
227 if (ret) {
228 dev_err(st->dev, "error reading data: %d\n", ret);
229 goto out;
230 }
231
232 iio_push_to_buffers_with_ts(indio_dev, &hw_values, sizeof(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_clear_bits(st->map, KXSD9_REG_CTRL_B, KXSD9_CTRL_B_ENABLE);
374 if (ret)
375 return ret;
376
377 /* Disable the regulators */
378 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs);
379 if (ret) {
380 dev_err(st->dev, "Cannot disable regulators\n");
381 return ret;
382 }
383
384 return 0;
385 }
386
387 static const struct iio_info kxsd9_info = {
388 .read_raw = &kxsd9_read_raw,
389 .write_raw = &kxsd9_write_raw,
390 .attrs = &kxsd9_attribute_group,
391 };
392
393 /* Four channels apart from timestamp, scan mask = 0x0f */
394 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 };
395
kxsd9_common_probe(struct device * dev,struct regmap * map,const char * name)396 int kxsd9_common_probe(struct device *dev,
397 struct regmap *map,
398 const char *name)
399 {
400 struct iio_dev *indio_dev;
401 struct kxsd9_state *st;
402 int ret;
403
404 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
405 if (!indio_dev)
406 return -ENOMEM;
407
408 st = iio_priv(indio_dev);
409 st->dev = dev;
410 st->map = map;
411
412 indio_dev->channels = kxsd9_channels;
413 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels);
414 indio_dev->name = name;
415 indio_dev->info = &kxsd9_info;
416 indio_dev->modes = INDIO_DIRECT_MODE;
417 indio_dev->available_scan_masks = kxsd9_scan_masks;
418
419 /* Read the mounting matrix, if present */
420 ret = iio_read_mount_matrix(dev, &st->orientation);
421 if (ret)
422 return ret;
423
424 /* Fetch and turn on regulators */
425 st->regs[0].supply = kxsd9_reg_vdd;
426 st->regs[1].supply = kxsd9_reg_iovdd;
427 ret = devm_regulator_bulk_get(dev,
428 ARRAY_SIZE(st->regs),
429 st->regs);
430 if (ret) {
431 dev_err(dev, "Cannot get regulators\n");
432 return ret;
433 }
434 /* Default scaling */
435 st->scale = KXSD9_CTRL_C_FS_2G;
436
437 kxsd9_power_up(st);
438
439 ret = iio_triggered_buffer_setup(indio_dev,
440 iio_pollfunc_store_time,
441 kxsd9_trigger_handler,
442 &kxsd9_buffer_setup_ops);
443 if (ret) {
444 dev_err(dev, "triggered buffer setup failed\n");
445 goto err_power_down;
446 }
447
448 ret = iio_device_register(indio_dev);
449 if (ret)
450 goto err_cleanup_buffer;
451
452 dev_set_drvdata(dev, indio_dev);
453
454 /* Enable runtime PM */
455 pm_runtime_get_noresume(dev);
456 pm_runtime_set_active(dev);
457 pm_runtime_enable(dev);
458 /*
459 * Set autosuspend to two orders of magnitude larger than the
460 * start-up time. 20ms start-up time means 2000ms autosuspend,
461 * i.e. 2 seconds.
462 */
463 pm_runtime_set_autosuspend_delay(dev, 2000);
464 pm_runtime_use_autosuspend(dev);
465 pm_runtime_put(dev);
466
467 return 0;
468
469 err_cleanup_buffer:
470 iio_triggered_buffer_cleanup(indio_dev);
471 err_power_down:
472 kxsd9_power_down(st);
473
474 return ret;
475 }
476 EXPORT_SYMBOL_NS(kxsd9_common_probe, "IIO_KXSD9");
477
kxsd9_common_remove(struct device * dev)478 void kxsd9_common_remove(struct device *dev)
479 {
480 struct iio_dev *indio_dev = dev_get_drvdata(dev);
481 struct kxsd9_state *st = iio_priv(indio_dev);
482
483 iio_triggered_buffer_cleanup(indio_dev);
484 iio_device_unregister(indio_dev);
485 pm_runtime_get_sync(dev);
486 pm_runtime_put_noidle(dev);
487 pm_runtime_disable(dev);
488 kxsd9_power_down(st);
489 }
490 EXPORT_SYMBOL_NS(kxsd9_common_remove, "IIO_KXSD9");
491
kxsd9_runtime_suspend(struct device * dev)492 static int kxsd9_runtime_suspend(struct device *dev)
493 {
494 struct iio_dev *indio_dev = dev_get_drvdata(dev);
495 struct kxsd9_state *st = iio_priv(indio_dev);
496
497 return kxsd9_power_down(st);
498 }
499
kxsd9_runtime_resume(struct device * dev)500 static int kxsd9_runtime_resume(struct device *dev)
501 {
502 struct iio_dev *indio_dev = dev_get_drvdata(dev);
503 struct kxsd9_state *st = iio_priv(indio_dev);
504
505 return kxsd9_power_up(st);
506 }
507
508 EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend,
509 kxsd9_runtime_resume, NULL, IIO_KXSD9);
510
511 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
512 MODULE_DESCRIPTION("Kionix KXSD9 driver");
513 MODULE_LICENSE("GPL v2");
514