xref: /kernel/linux/linux-6.6/drivers/iio/accel/kxsd9.c (revision 62306a36)
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 */
72struct 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 */
86static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 };
87
88#define KXSD9_ZERO_G_OFFSET -2048
89
90/*
91 * Regulator names
92 */
93static const char kxsd9_reg_vdd[] = "vdd";
94static const char kxsd9_reg_iovdd[] = "iovdd";
95
96static 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
120error_ret:
121	return ret;
122}
123
124static IIO_CONST_ATTR(accel_scale_available,
125		KXSD9_SCALE_2G " "
126		KXSD9_SCALE_4G " "
127		KXSD9_SCALE_6G " "
128		KXSD9_SCALE_8G);
129
130static struct attribute *kxsd9_attributes[] = {
131	&iio_const_attr_accel_scale_available.dev_attr.attr,
132	NULL,
133};
134
135static 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
159static 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				  &regval);
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
200error_ret:
201	pm_runtime_mark_last_busy(st->dev);
202	pm_runtime_put_autosuspend(st->dev);
203
204	return ret;
205};
206
207static 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));
234out:
235	iio_trigger_notify_done(indio_dev->trig);
236
237	return IRQ_HANDLED;
238}
239
240static 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
249static 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
259static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = {
260	.preenable = kxsd9_buffer_preenable,
261	.postdisable = kxsd9_buffer_postdisable,
262};
263
264static const struct iio_mount_matrix *
265kxsd9_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
273static 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
298static 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
319static const struct attribute_group kxsd9_attribute_group = {
320	.attrs = kxsd9_attributes,
321};
322
323static 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
363static 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
390static 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 */
397static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 };
398
399int 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, &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
472err_cleanup_buffer:
473	iio_triggered_buffer_cleanup(indio_dev);
474err_power_down:
475	kxsd9_power_down(st);
476
477	return ret;
478}
479EXPORT_SYMBOL_NS(kxsd9_common_probe, IIO_KXSD9);
480
481void 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}
493EXPORT_SYMBOL_NS(kxsd9_common_remove, IIO_KXSD9);
494
495static int kxsd9_runtime_suspend(struct device *dev)
496{
497	struct iio_dev *indio_dev = dev_get_drvdata(dev);
498	struct kxsd9_state *st = iio_priv(indio_dev);
499
500	return kxsd9_power_down(st);
501}
502
503static int kxsd9_runtime_resume(struct device *dev)
504{
505	struct iio_dev *indio_dev = dev_get_drvdata(dev);
506	struct kxsd9_state *st = iio_priv(indio_dev);
507
508	return kxsd9_power_up(st);
509}
510
511EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend,
512			     kxsd9_runtime_resume, NULL, IIO_KXSD9);
513
514MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
515MODULE_DESCRIPTION("Kionix KXSD9 driver");
516MODULE_LICENSE("GPL v2");
517