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8#include <linux/acpi.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/iio/buffer.h>
12#include <linux/iio/iio.h>
13#include <linux/iio/sysfs.h>
14#include <linux/spi/spi.h>
15#include <linux/iio/trigger_consumer.h>
16#include <linux/iio/triggered_buffer.h>
17
18#define BMA220_REG_ID 0x00
19#define BMA220_REG_ACCEL_X 0x02
20#define BMA220_REG_ACCEL_Y 0x03
21#define BMA220_REG_ACCEL_Z 0x04
22#define BMA220_REG_RANGE 0x11
23#define BMA220_REG_SUSPEND 0x18
24
25#define BMA220_CHIP_ID 0xDD
26#define BMA220_READ_MASK 0x80
27#define BMA220_RANGE_MASK 0x03
28#define BMA220_DATA_SHIFT 2
29#define BMA220_SUSPEND_SLEEP 0xFF
30#define BMA220_SUSPEND_WAKE 0x00
31
32#define BMA220_DEVICE_NAME "bma220"
33#define BMA220_SCALE_AVAILABLE "0.623 1.248 2.491 4.983"
34
35#define BMA220_ACCEL_CHANNEL(index, reg, axis) { \
36 .type = IIO_ACCEL, \
37 .address = reg, \
38 .modified = 1, \
39 .channel2 = IIO_MOD_##axis, \
40 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
41 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
42 .scan_index = index, \
43 .scan_type = { \
44 .sign = 's', \
45 .realbits = 6, \
46 .storagebits = 8, \
47 .shift = BMA220_DATA_SHIFT, \
48 .endianness = IIO_CPU, \
49 }, \
50}
51
52enum bma220_axis {
53 AXIS_X,
54 AXIS_Y,
55 AXIS_Z,
56};
57
58static IIO_CONST_ATTR(in_accel_scale_available, BMA220_SCALE_AVAILABLE);
59
60static struct attribute *bma220_attributes[] = {
61 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
62 NULL,
63};
64
65static const struct attribute_group bma220_attribute_group = {
66 .attrs = bma220_attributes,
67};
68
69static const int bma220_scale_table[][4] = {
70 {0, 623000}, {1, 248000}, {2, 491000}, {4, 983000}
71};
72
73struct bma220_data {
74 struct spi_device *spi_device;
75 struct mutex lock;
76 s8 buffer[16];
77 u8 tx_buf[2] ____cacheline_aligned;
78};
79
80static const struct iio_chan_spec bma220_channels[] = {
81 BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
82 BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
83 BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
84 IIO_CHAN_SOFT_TIMESTAMP(3),
85};
86
87static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
88{
89 return spi_w8r8(spi, reg | BMA220_READ_MASK);
90}
91
92static const unsigned long bma220_accel_scan_masks[] = {
93 BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
94 0
95};
96
97static irqreturn_t bma220_trigger_handler(int irq, void *p)
98{
99 int ret;
100 struct iio_poll_func *pf = p;
101 struct iio_dev *indio_dev = pf->indio_dev;
102 struct bma220_data *data = iio_priv(indio_dev);
103 struct spi_device *spi = data->spi_device;
104
105 mutex_lock(&data->lock);
106 data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
107 ret = spi_write_then_read(spi, data->tx_buf, 1, data->buffer,
108 ARRAY_SIZE(bma220_channels) - 1);
109 if (ret < 0)
110 goto err;
111
112 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
113 pf->timestamp);
114err:
115 mutex_unlock(&data->lock);
116 iio_trigger_notify_done(indio_dev->trig);
117
118 return IRQ_HANDLED;
119}
120
121static int bma220_read_raw(struct iio_dev *indio_dev,
122 struct iio_chan_spec const *chan,
123 int *val, int *val2, long mask)
124{
125 int ret;
126 u8 range_idx;
127 struct bma220_data *data = iio_priv(indio_dev);
128
129 switch (mask) {
130 case IIO_CHAN_INFO_RAW:
131 ret = bma220_read_reg(data->spi_device, chan->address);
132 if (ret < 0)
133 return -EINVAL;
134 *val = sign_extend32(ret >> BMA220_DATA_SHIFT, 5);
135 return IIO_VAL_INT;
136 case IIO_CHAN_INFO_SCALE:
137 ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
138 if (ret < 0)
139 return ret;
140 range_idx = ret & BMA220_RANGE_MASK;
141 *val = bma220_scale_table[range_idx][0];
142 *val2 = bma220_scale_table[range_idx][1];
143 return IIO_VAL_INT_PLUS_MICRO;
144 }
145
146 return -EINVAL;
147}
148
149static int bma220_write_raw(struct iio_dev *indio_dev,
150 struct iio_chan_spec const *chan,
151 int val, int val2, long mask)
152{
153 int i;
154 int ret;
155 int index = -1;
156 struct bma220_data *data = iio_priv(indio_dev);
157
158 switch (mask) {
159 case IIO_CHAN_INFO_SCALE:
160 for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
161 if (val == bma220_scale_table[i][0] &&
162 val2 == bma220_scale_table[i][1]) {
163 index = i;
164 break;
165 }
166 if (index < 0)
167 return -EINVAL;
168
169 mutex_lock(&data->lock);
170 data->tx_buf[0] = BMA220_REG_RANGE;
171 data->tx_buf[1] = index;
172 ret = spi_write(data->spi_device, data->tx_buf,
173 sizeof(data->tx_buf));
174 if (ret < 0)
175 dev_err(&data->spi_device->dev,
176 "failed to set measurement range\n");
177 mutex_unlock(&data->lock);
178
179 return 0;
180 }
181
182 return -EINVAL;
183}
184
185static const struct iio_info bma220_info = {
186 .read_raw = bma220_read_raw,
187 .write_raw = bma220_write_raw,
188 .attrs = &bma220_attribute_group,
189};
190
191static int bma220_init(struct spi_device *spi)
192{
193 int ret;
194
195 ret = bma220_read_reg(spi, BMA220_REG_ID);
196 if (ret != BMA220_CHIP_ID)
197 return -ENODEV;
198
199
200 ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
201 if (ret < 0)
202 return ret;
203 else if (ret == BMA220_SUSPEND_WAKE)
204 return bma220_read_reg(spi, BMA220_REG_SUSPEND);
205
206 return 0;
207}
208
209static int bma220_deinit(struct spi_device *spi)
210{
211 int ret;
212
213
214 ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
215 if (ret < 0)
216 return ret;
217 else if (ret == BMA220_SUSPEND_SLEEP)
218 return bma220_read_reg(spi, BMA220_REG_SUSPEND);
219
220 return 0;
221}
222
223static int bma220_probe(struct spi_device *spi)
224{
225 int ret;
226 struct iio_dev *indio_dev;
227 struct bma220_data *data;
228
229 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
230 if (!indio_dev) {
231 dev_err(&spi->dev, "iio allocation failed!\n");
232 return -ENOMEM;
233 }
234
235 data = iio_priv(indio_dev);
236 data->spi_device = spi;
237 spi_set_drvdata(spi, indio_dev);
238 mutex_init(&data->lock);
239
240 indio_dev->dev.parent = &spi->dev;
241 indio_dev->info = &bma220_info;
242 indio_dev->name = BMA220_DEVICE_NAME;
243 indio_dev->modes = INDIO_DIRECT_MODE;
244 indio_dev->channels = bma220_channels;
245 indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
246 indio_dev->available_scan_masks = bma220_accel_scan_masks;
247
248 ret = bma220_init(data->spi_device);
249 if (ret < 0)
250 return ret;
251
252 ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
253 bma220_trigger_handler, NULL);
254 if (ret < 0) {
255 dev_err(&spi->dev, "iio triggered buffer setup failed\n");
256 goto err_suspend;
257 }
258
259 ret = iio_device_register(indio_dev);
260 if (ret < 0) {
261 dev_err(&spi->dev, "iio_device_register failed\n");
262 iio_triggered_buffer_cleanup(indio_dev);
263 goto err_suspend;
264 }
265
266 return 0;
267
268err_suspend:
269 return bma220_deinit(spi);
270}
271
272static int bma220_remove(struct spi_device *spi)
273{
274 struct iio_dev *indio_dev = spi_get_drvdata(spi);
275
276 iio_device_unregister(indio_dev);
277 iio_triggered_buffer_cleanup(indio_dev);
278
279 return bma220_deinit(spi);
280}
281
282#ifdef CONFIG_PM_SLEEP
283static int bma220_suspend(struct device *dev)
284{
285 struct bma220_data *data =
286 iio_priv(spi_get_drvdata(to_spi_device(dev)));
287
288
289 return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
290}
291
292static int bma220_resume(struct device *dev)
293{
294 struct bma220_data *data =
295 iio_priv(spi_get_drvdata(to_spi_device(dev)));
296
297 return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
298}
299
300static SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
301
302#define BMA220_PM_OPS (&bma220_pm_ops)
303#else
304#define BMA220_PM_OPS NULL
305#endif
306
307static const struct spi_device_id bma220_spi_id[] = {
308 {"bma220", 0},
309 {}
310};
311
312static const struct acpi_device_id bma220_acpi_id[] = {
313 {"BMA0220", 0},
314 {}
315};
316
317MODULE_DEVICE_TABLE(spi, bma220_spi_id);
318
319static struct spi_driver bma220_driver = {
320 .driver = {
321 .name = "bma220_spi",
322 .pm = BMA220_PM_OPS,
323 .acpi_match_table = ACPI_PTR(bma220_acpi_id),
324 },
325 .probe = bma220_probe,
326 .remove = bma220_remove,
327 .id_table = bma220_spi_id,
328};
329
330module_spi_driver(bma220_driver);
331
332MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
333MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
334MODULE_LICENSE("GPL v2");
335
