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11#include <linux/acpi.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/iio/buffer.h>
15#include <linux/iio/iio.h>
16#include <linux/iio/sysfs.h>
17#include <linux/spi/spi.h>
18#include <linux/iio/trigger_consumer.h>
19#include <linux/iio/triggered_buffer.h>
20
21#define BMA220_REG_ID 0x00
22#define BMA220_REG_ACCEL_X 0x02
23#define BMA220_REG_ACCEL_Y 0x03
24#define BMA220_REG_ACCEL_Z 0x04
25#define BMA220_REG_RANGE 0x11
26#define BMA220_REG_SUSPEND 0x18
27
28#define BMA220_CHIP_ID 0xDD
29#define BMA220_READ_MASK 0x80
30#define BMA220_RANGE_MASK 0x03
31#define BMA220_DATA_SHIFT 2
32#define BMA220_SUSPEND_SLEEP 0xFF
33#define BMA220_SUSPEND_WAKE 0x00
34
35#define BMA220_DEVICE_NAME "bma220"
36#define BMA220_SCALE_AVAILABLE "0.623 1.248 2.491 4.983"
37
38#define BMA220_ACCEL_CHANNEL(index, reg, axis) { \
39 .type = IIO_ACCEL, \
40 .address = reg, \
41 .modified = 1, \
42 .channel2 = IIO_MOD_##axis, \
43 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
44 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
45 .scan_index = index, \
46 .scan_type = { \
47 .sign = 's', \
48 .realbits = 6, \
49 .storagebits = 8, \
50 .shift = BMA220_DATA_SHIFT, \
51 .endianness = IIO_CPU, \
52 }, \
53}
54
55enum bma220_axis {
56 AXIS_X,
57 AXIS_Y,
58 AXIS_Z,
59};
60
61static IIO_CONST_ATTR(in_accel_scale_available, BMA220_SCALE_AVAILABLE);
62
63static struct attribute *bma220_attributes[] = {
64 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
65 NULL,
66};
67
68static const struct attribute_group bma220_attribute_group = {
69 .attrs = bma220_attributes,
70};
71
72static const int bma220_scale_table[][4] = {
73 {0, 623000}, {1, 248000}, {2, 491000}, {4, 983000}
74};
75
76struct bma220_data {
77 struct spi_device *spi_device;
78 struct mutex lock;
79 s8 buffer[16];
80 u8 tx_buf[2] ____cacheline_aligned;
81};
82
83static const struct iio_chan_spec bma220_channels[] = {
84 BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
85 BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
86 BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
87 IIO_CHAN_SOFT_TIMESTAMP(3),
88};
89
90static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
91{
92 return spi_w8r8(spi, reg | BMA220_READ_MASK);
93}
94
95static const unsigned long bma220_accel_scan_masks[] = {
96 BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
97 0
98};
99
100static irqreturn_t bma220_trigger_handler(int irq, void *p)
101{
102 int ret;
103 struct iio_poll_func *pf = p;
104 struct iio_dev *indio_dev = pf->indio_dev;
105 struct bma220_data *data = iio_priv(indio_dev);
106 struct spi_device *spi = data->spi_device;
107
108 mutex_lock(&data->lock);
109 data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
110 ret = spi_write_then_read(spi, data->tx_buf, 1, data->buffer,
111 ARRAY_SIZE(bma220_channels) - 1);
112 if (ret < 0)
113 goto err;
114
115 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
116 pf->timestamp);
117err:
118 mutex_unlock(&data->lock);
119 iio_trigger_notify_done(indio_dev->trig);
120
121 return IRQ_HANDLED;
122}
123
124static int bma220_read_raw(struct iio_dev *indio_dev,
125 struct iio_chan_spec const *chan,
126 int *val, int *val2, long mask)
127{
128 int ret;
129 u8 range_idx;
130 struct bma220_data *data = iio_priv(indio_dev);
131
132 switch (mask) {
133 case IIO_CHAN_INFO_RAW:
134 ret = bma220_read_reg(data->spi_device, chan->address);
135 if (ret < 0)
136 return -EINVAL;
137 *val = sign_extend32(ret >> BMA220_DATA_SHIFT, 5);
138 return IIO_VAL_INT;
139 case IIO_CHAN_INFO_SCALE:
140 ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
141 if (ret < 0)
142 return ret;
143 range_idx = ret & BMA220_RANGE_MASK;
144 *val = bma220_scale_table[range_idx][0];
145 *val2 = bma220_scale_table[range_idx][1];
146 return IIO_VAL_INT_PLUS_MICRO;
147 }
148
149 return -EINVAL;
150}
151
152static int bma220_write_raw(struct iio_dev *indio_dev,
153 struct iio_chan_spec const *chan,
154 int val, int val2, long mask)
155{
156 int i;
157 int ret;
158 int index = -1;
159 struct bma220_data *data = iio_priv(indio_dev);
160
161 switch (mask) {
162 case IIO_CHAN_INFO_SCALE:
163 for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
164 if (val == bma220_scale_table[i][0] &&
165 val2 == bma220_scale_table[i][1]) {
166 index = i;
167 break;
168 }
169 if (index < 0)
170 return -EINVAL;
171
172 mutex_lock(&data->lock);
173 data->tx_buf[0] = BMA220_REG_RANGE;
174 data->tx_buf[1] = index;
175 ret = spi_write(data->spi_device, data->tx_buf,
176 sizeof(data->tx_buf));
177 if (ret < 0)
178 dev_err(&data->spi_device->dev,
179 "failed to set measurement range\n");
180 mutex_unlock(&data->lock);
181
182 return 0;
183 }
184
185 return -EINVAL;
186}
187
188static const struct iio_info bma220_info = {
189 .driver_module = THIS_MODULE,
190 .read_raw = bma220_read_raw,
191 .write_raw = bma220_write_raw,
192 .attrs = &bma220_attribute_group,
193};
194
195static int bma220_init(struct spi_device *spi)
196{
197 int ret;
198
199 ret = bma220_read_reg(spi, BMA220_REG_ID);
200 if (ret != BMA220_CHIP_ID)
201 return -ENODEV;
202
203
204 ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
205 if (ret < 0)
206 return ret;
207 else if (ret == BMA220_SUSPEND_WAKE)
208 return bma220_read_reg(spi, BMA220_REG_SUSPEND);
209
210 return 0;
211}
212
213static int bma220_deinit(struct spi_device *spi)
214{
215 int ret;
216
217
218 ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
219 if (ret < 0)
220 return ret;
221 else if (ret == BMA220_SUSPEND_SLEEP)
222 return bma220_read_reg(spi, BMA220_REG_SUSPEND);
223
224 return 0;
225}
226
227static int bma220_probe(struct spi_device *spi)
228{
229 int ret;
230 struct iio_dev *indio_dev;
231 struct bma220_data *data;
232
233 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
234 if (!indio_dev) {
235 dev_err(&spi->dev, "iio allocation failed!\n");
236 return -ENOMEM;
237 }
238
239 data = iio_priv(indio_dev);
240 data->spi_device = spi;
241 spi_set_drvdata(spi, indio_dev);
242 mutex_init(&data->lock);
243
244 indio_dev->dev.parent = &spi->dev;
245 indio_dev->info = &bma220_info;
246 indio_dev->name = BMA220_DEVICE_NAME;
247 indio_dev->modes = INDIO_DIRECT_MODE;
248 indio_dev->channels = bma220_channels;
249 indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
250 indio_dev->available_scan_masks = bma220_accel_scan_masks;
251
252 ret = bma220_init(data->spi_device);
253 if (ret < 0)
254 return ret;
255
256 ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
257 bma220_trigger_handler, NULL);
258 if (ret < 0) {
259 dev_err(&spi->dev, "iio triggered buffer setup failed\n");
260 goto err_suspend;
261 }
262
263 ret = iio_device_register(indio_dev);
264 if (ret < 0) {
265 dev_err(&spi->dev, "iio_device_register failed\n");
266 iio_triggered_buffer_cleanup(indio_dev);
267 goto err_suspend;
268 }
269
270 return 0;
271
272err_suspend:
273 return bma220_deinit(spi);
274}
275
276static int bma220_remove(struct spi_device *spi)
277{
278 struct iio_dev *indio_dev = spi_get_drvdata(spi);
279
280 iio_device_unregister(indio_dev);
281 iio_triggered_buffer_cleanup(indio_dev);
282
283 return bma220_deinit(spi);
284}
285
286#ifdef CONFIG_PM_SLEEP
287static int bma220_suspend(struct device *dev)
288{
289 struct bma220_data *data =
290 iio_priv(spi_get_drvdata(to_spi_device(dev)));
291
292
293 return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
294}
295
296static int bma220_resume(struct device *dev)
297{
298 struct bma220_data *data =
299 iio_priv(spi_get_drvdata(to_spi_device(dev)));
300
301 return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
302}
303
304static SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
305
306#define BMA220_PM_OPS (&bma220_pm_ops)
307#else
308#define BMA220_PM_OPS NULL
309#endif
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};
320
321MODULE_DEVICE_TABLE(spi, bma220_spi_id);
322
323static struct spi_driver bma220_driver = {
324 .driver = {
325 .name = "bma220_spi",
326 .pm = BMA220_PM_OPS,
327 .acpi_match_table = ACPI_PTR(bma220_acpi_id),
328 },
329 .probe = bma220_probe,
330 .remove = bma220_remove,
331 .id_table = bma220_spi_id,
332};
333
334module_spi_driver(bma220_driver);
335
336MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
337MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
338MODULE_LICENSE("GPL v2");
339
