1// SPDX-License-Identifier: GPL-2.0-only
2/**
3 * BMA220 Digital triaxial acceleration sensor driver
4 *
5 * Copyright (c) 2016,2020 Intel Corporation.
6 */
7
8#include <linux/bits.h>
9#include <linux/kernel.h>
10#include <linux/mod_devicetable.h>
11#include <linux/module.h>
12#include <linux/spi/spi.h>
13
14#include <linux/iio/buffer.h>
15#include <linux/iio/iio.h>
16#include <linux/iio/sysfs.h>
17#include <linux/iio/trigger_consumer.h>
18#include <linux/iio/triggered_buffer.h>
19
20#define BMA220_REG_ID				0x00
21#define BMA220_REG_ACCEL_X			0x02
22#define BMA220_REG_ACCEL_Y			0x03
23#define BMA220_REG_ACCEL_Z			0x04
24#define BMA220_REG_RANGE			0x11
25#define BMA220_REG_SUSPEND			0x18
26
27#define BMA220_CHIP_ID				0xDD
28#define BMA220_READ_MASK			BIT(7)
29#define BMA220_RANGE_MASK			GENMASK(1, 0)
30#define BMA220_DATA_SHIFT			2
31#define BMA220_SUSPEND_SLEEP			0xFF
32#define BMA220_SUSPEND_WAKE			0x00
33
34#define BMA220_DEVICE_NAME			"bma220"
35
36#define BMA220_ACCEL_CHANNEL(index, reg, axis) {			\
37	.type = IIO_ACCEL,						\
38	.address = reg,							\
39	.modified = 1,							\
40	.channel2 = IIO_MOD_##axis,					\
41	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
42	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
43	.scan_index = index,						\
44	.scan_type = {							\
45		.sign = 's',						\
46		.realbits = 6,						\
47		.storagebits = 8,					\
48		.shift = BMA220_DATA_SHIFT,				\
49		.endianness = IIO_CPU,					\
50	},								\
51}
52
53enum bma220_axis {
54	AXIS_X,
55	AXIS_Y,
56	AXIS_Z,
57};
58
59static const int bma220_scale_table[][2] = {
60	{0, 623000}, {1, 248000}, {2, 491000}, {4, 983000},
61};
62
63struct bma220_data {
64	struct spi_device *spi_device;
65	struct mutex lock;
66	struct {
67		s8 chans[3];
68		/* Ensure timestamp is naturally aligned. */
69		s64 timestamp __aligned(8);
70	} scan;
71	u8 tx_buf[2] ____cacheline_aligned;
72};
73
74static const struct iio_chan_spec bma220_channels[] = {
75	BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
76	BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
77	BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
78	IIO_CHAN_SOFT_TIMESTAMP(3),
79};
80
81static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
82{
83	return spi_w8r8(spi, reg | BMA220_READ_MASK);
84}
85
86static const unsigned long bma220_accel_scan_masks[] = {
87	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
88	0
89};
90
91static irqreturn_t bma220_trigger_handler(int irq, void *p)
92{
93	int ret;
94	struct iio_poll_func *pf = p;
95	struct iio_dev *indio_dev = pf->indio_dev;
96	struct bma220_data *data = iio_priv(indio_dev);
97	struct spi_device *spi = data->spi_device;
98
99	mutex_lock(&data->lock);
100	data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
101	ret = spi_write_then_read(spi, data->tx_buf, 1, &data->scan.chans,
102				  ARRAY_SIZE(bma220_channels) - 1);
103	if (ret < 0)
104		goto err;
105
106	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
107					   pf->timestamp);
108err:
109	mutex_unlock(&data->lock);
110	iio_trigger_notify_done(indio_dev->trig);
111
112	return IRQ_HANDLED;
113}
114
115static int bma220_read_raw(struct iio_dev *indio_dev,
116			   struct iio_chan_spec const *chan,
117			   int *val, int *val2, long mask)
118{
119	int ret;
120	u8 range_idx;
121	struct bma220_data *data = iio_priv(indio_dev);
122
123	switch (mask) {
124	case IIO_CHAN_INFO_RAW:
125		ret = bma220_read_reg(data->spi_device, chan->address);
126		if (ret < 0)
127			return -EINVAL;
128		*val = sign_extend32(ret >> BMA220_DATA_SHIFT, 5);
129		return IIO_VAL_INT;
130	case IIO_CHAN_INFO_SCALE:
131		ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
132		if (ret < 0)
133			return ret;
134		range_idx = ret & BMA220_RANGE_MASK;
135		*val = bma220_scale_table[range_idx][0];
136		*val2 = bma220_scale_table[range_idx][1];
137		return IIO_VAL_INT_PLUS_MICRO;
138	}
139
140	return -EINVAL;
141}
142
143static int bma220_write_raw(struct iio_dev *indio_dev,
144			    struct iio_chan_spec const *chan,
145			    int val, int val2, long mask)
146{
147	int i;
148	int ret;
149	int index = -1;
150	struct bma220_data *data = iio_priv(indio_dev);
151
152	switch (mask) {
153	case IIO_CHAN_INFO_SCALE:
154		for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
155			if (val == bma220_scale_table[i][0] &&
156			    val2 == bma220_scale_table[i][1]) {
157				index = i;
158				break;
159			}
160		if (index < 0)
161			return -EINVAL;
162
163		mutex_lock(&data->lock);
164		data->tx_buf[0] = BMA220_REG_RANGE;
165		data->tx_buf[1] = index;
166		ret = spi_write(data->spi_device, data->tx_buf,
167				sizeof(data->tx_buf));
168		if (ret < 0)
169			dev_err(&data->spi_device->dev,
170				"failed to set measurement range\n");
171		mutex_unlock(&data->lock);
172
173		return 0;
174	}
175
176	return -EINVAL;
177}
178
179static int bma220_read_avail(struct iio_dev *indio_dev,
180			     struct iio_chan_spec const *chan,
181			     const int **vals, int *type, int *length,
182			     long mask)
183{
184	switch (mask) {
185	case IIO_CHAN_INFO_SCALE:
186		*vals = (int *)bma220_scale_table;
187		*type = IIO_VAL_INT_PLUS_MICRO;
188		*length = ARRAY_SIZE(bma220_scale_table) * 2;
189		return IIO_AVAIL_LIST;
190	default:
191		return -EINVAL;
192	}
193}
194
195static const struct iio_info bma220_info = {
196	.read_raw		= bma220_read_raw,
197	.write_raw		= bma220_write_raw,
198	.read_avail		= bma220_read_avail,
199};
200
201static int bma220_init(struct spi_device *spi)
202{
203	int ret;
204
205	ret = bma220_read_reg(spi, BMA220_REG_ID);
206	if (ret != BMA220_CHIP_ID)
207		return -ENODEV;
208
209	/* Make sure the chip is powered on */
210	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
211	if (ret == BMA220_SUSPEND_WAKE)
212		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
213	if (ret < 0)
214		return ret;
215	if (ret == BMA220_SUSPEND_WAKE)
216		return -EBUSY;
217
218	return 0;
219}
220
221static int bma220_deinit(struct spi_device *spi)
222{
223	int ret;
224
225	/* Make sure the chip is powered off */
226	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
227	if (ret == BMA220_SUSPEND_SLEEP)
228		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
229	if (ret < 0)
230		return ret;
231	if (ret == BMA220_SUSPEND_SLEEP)
232		return -EBUSY;
233
234	return 0;
235}
236
237static int bma220_probe(struct spi_device *spi)
238{
239	int ret;
240	struct iio_dev *indio_dev;
241	struct bma220_data *data;
242
243	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
244	if (!indio_dev) {
245		dev_err(&spi->dev, "iio allocation failed!\n");
246		return -ENOMEM;
247	}
248
249	data = iio_priv(indio_dev);
250	data->spi_device = spi;
251	spi_set_drvdata(spi, indio_dev);
252	mutex_init(&data->lock);
253
254	indio_dev->info = &bma220_info;
255	indio_dev->name = BMA220_DEVICE_NAME;
256	indio_dev->modes = INDIO_DIRECT_MODE;
257	indio_dev->channels = bma220_channels;
258	indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
259	indio_dev->available_scan_masks = bma220_accel_scan_masks;
260
261	ret = bma220_init(data->spi_device);
262	if (ret)
263		return ret;
264
265	ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
266					 bma220_trigger_handler, NULL);
267	if (ret < 0) {
268		dev_err(&spi->dev, "iio triggered buffer setup failed\n");
269		goto err_suspend;
270	}
271
272	ret = iio_device_register(indio_dev);
273	if (ret < 0) {
274		dev_err(&spi->dev, "iio_device_register failed\n");
275		iio_triggered_buffer_cleanup(indio_dev);
276		goto err_suspend;
277	}
278
279	return 0;
280
281err_suspend:
282	return bma220_deinit(spi);
283}
284
285static int bma220_remove(struct spi_device *spi)
286{
287	struct iio_dev *indio_dev = spi_get_drvdata(spi);
288
289	iio_device_unregister(indio_dev);
290	iio_triggered_buffer_cleanup(indio_dev);
291
292	return bma220_deinit(spi);
293}
294
295static __maybe_unused int bma220_suspend(struct device *dev)
296{
297	struct bma220_data *data = iio_priv(dev_get_drvdata(dev));
298
299	/* The chip can be suspended/woken up by a simple register read. */
300	return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
301}
302
303static __maybe_unused int bma220_resume(struct device *dev)
304{
305	struct bma220_data *data = iio_priv(dev_get_drvdata(dev));
306
307	return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
308}
309static SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
310
311static const struct spi_device_id bma220_spi_id[] = {
312	{"bma220", 0},
313	{}
314};
315
316static const struct acpi_device_id bma220_acpi_id[] = {
317	{"BMA0220", 0},
318	{}
319};
320MODULE_DEVICE_TABLE(spi, bma220_spi_id);
321
322static struct spi_driver bma220_driver = {
323	.driver = {
324		.name = "bma220_spi",
325		.pm = &bma220_pm_ops,
326		.acpi_match_table = bma220_acpi_id,
327	},
328	.probe =            bma220_probe,
329	.remove =           bma220_remove,
330	.id_table =         bma220_spi_id,
331};
332module_spi_driver(bma220_driver);
333
334MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
335MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
336MODULE_LICENSE("GPL v2");
337