1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * cros_ec_sensors_core - Common function for Chrome OS EC sensor driver.
4 *
5 * Copyright (C) 2016 Google, Inc
6 */
7
8 #include <linux/delay.h>
9 #include <linux/device.h>
10 #include <linux/iio/buffer.h>
11 #include <linux/iio/common/cros_ec_sensors_core.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/kfifo_buf.h>
14 #include <linux/iio/sysfs.h>
15 #include <linux/iio/trigger.h>
16 #include <linux/iio/trigger_consumer.h>
17 #include <linux/iio/triggered_buffer.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
21 #include <linux/platform_data/cros_ec_commands.h>
22 #include <linux/platform_data/cros_ec_proto.h>
23 #include <linux/platform_data/cros_ec_sensorhub.h>
24 #include <linux/platform_device.h>
25
26 /*
27 * Hard coded to the first device to support sensor fifo. The EC has a 2048
28 * byte fifo and will trigger an interrupt when fifo is 2/3 full.
29 */
30 #define CROS_EC_FIFO_SIZE (2048 * 2 / 3)
31
cros_ec_get_host_cmd_version_mask(struct cros_ec_device * ec_dev,u16 cmd_offset,u16 cmd,u32 * mask)32 static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev,
33 u16 cmd_offset, u16 cmd, u32 *mask)
34 {
35 int ret;
36 struct {
37 struct cros_ec_command msg;
38 union {
39 struct ec_params_get_cmd_versions params;
40 struct ec_response_get_cmd_versions resp;
41 };
42 } __packed buf = {
43 .msg = {
44 .command = EC_CMD_GET_CMD_VERSIONS + cmd_offset,
45 .insize = sizeof(struct ec_response_get_cmd_versions),
46 .outsize = sizeof(struct ec_params_get_cmd_versions)
47 },
48 .params = {.cmd = cmd}
49 };
50
51 ret = cros_ec_cmd_xfer_status(ec_dev, &buf.msg);
52 if (ret >= 0)
53 *mask = buf.resp.version_mask;
54 return ret;
55 }
56
get_default_min_max_freq(enum motionsensor_type type,u32 * min_freq,u32 * max_freq,u32 * max_fifo_events)57 static void get_default_min_max_freq(enum motionsensor_type type,
58 u32 *min_freq,
59 u32 *max_freq,
60 u32 *max_fifo_events)
61 {
62 /*
63 * We don't know fifo size, set to size previously used by older
64 * hardware.
65 */
66 *max_fifo_events = CROS_EC_FIFO_SIZE;
67
68 switch (type) {
69 case MOTIONSENSE_TYPE_ACCEL:
70 *min_freq = 12500;
71 *max_freq = 100000;
72 break;
73 case MOTIONSENSE_TYPE_GYRO:
74 *min_freq = 25000;
75 *max_freq = 100000;
76 break;
77 case MOTIONSENSE_TYPE_MAG:
78 *min_freq = 5000;
79 *max_freq = 25000;
80 break;
81 case MOTIONSENSE_TYPE_PROX:
82 case MOTIONSENSE_TYPE_LIGHT:
83 *min_freq = 100;
84 *max_freq = 50000;
85 break;
86 case MOTIONSENSE_TYPE_BARO:
87 *min_freq = 250;
88 *max_freq = 20000;
89 break;
90 case MOTIONSENSE_TYPE_ACTIVITY:
91 default:
92 *min_freq = 0;
93 *max_freq = 0;
94 break;
95 }
96 }
97
cros_ec_sensor_set_ec_rate(struct cros_ec_sensors_core_state * st,int rate)98 static int cros_ec_sensor_set_ec_rate(struct cros_ec_sensors_core_state *st,
99 int rate)
100 {
101 int ret;
102
103 if (rate > U16_MAX)
104 rate = U16_MAX;
105
106 mutex_lock(&st->cmd_lock);
107 st->param.cmd = MOTIONSENSE_CMD_EC_RATE;
108 st->param.ec_rate.data = rate;
109 ret = cros_ec_motion_send_host_cmd(st, 0);
110 mutex_unlock(&st->cmd_lock);
111 return ret;
112 }
113
cros_ec_sensor_set_report_latency(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)114 static ssize_t cros_ec_sensor_set_report_latency(struct device *dev,
115 struct device_attribute *attr,
116 const char *buf, size_t len)
117 {
118 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
119 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
120 int integer, fract, ret;
121 int latency;
122
123 ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
124 if (ret)
125 return ret;
126
127 /* EC rate is in ms. */
128 latency = integer * 1000 + fract / 1000;
129 ret = cros_ec_sensor_set_ec_rate(st, latency);
130 if (ret < 0)
131 return ret;
132
133 return len;
134 }
135
cros_ec_sensor_get_report_latency(struct device * dev,struct device_attribute * attr,char * buf)136 static ssize_t cros_ec_sensor_get_report_latency(struct device *dev,
137 struct device_attribute *attr,
138 char *buf)
139 {
140 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
141 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
142 int latency, ret;
143
144 mutex_lock(&st->cmd_lock);
145 st->param.cmd = MOTIONSENSE_CMD_EC_RATE;
146 st->param.ec_rate.data = EC_MOTION_SENSE_NO_VALUE;
147
148 ret = cros_ec_motion_send_host_cmd(st, 0);
149 latency = st->resp->ec_rate.ret;
150 mutex_unlock(&st->cmd_lock);
151 if (ret < 0)
152 return ret;
153
154 return sprintf(buf, "%d.%06u\n",
155 latency / 1000,
156 (latency % 1000) * 1000);
157 }
158
159 static IIO_DEVICE_ATTR(hwfifo_timeout, 0644,
160 cros_ec_sensor_get_report_latency,
161 cros_ec_sensor_set_report_latency, 0);
162
hwfifo_watermark_max_show(struct device * dev,struct device_attribute * attr,char * buf)163 static ssize_t hwfifo_watermark_max_show(struct device *dev,
164 struct device_attribute *attr,
165 char *buf)
166 {
167 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
168 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
169
170 return sprintf(buf, "%d\n", st->fifo_max_event_count);
171 }
172
173 static IIO_DEVICE_ATTR_RO(hwfifo_watermark_max, 0);
174
175 static const struct iio_dev_attr *cros_ec_sensor_fifo_attributes[] = {
176 &iio_dev_attr_hwfifo_timeout,
177 &iio_dev_attr_hwfifo_watermark_max,
178 NULL,
179 };
180
cros_ec_sensors_push_data(struct iio_dev * indio_dev,s16 * data,s64 timestamp)181 int cros_ec_sensors_push_data(struct iio_dev *indio_dev,
182 s16 *data,
183 s64 timestamp)
184 {
185 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
186 s16 *out;
187 s64 delta;
188 unsigned int i;
189
190 /*
191 * Ignore samples if the buffer is not set: it is needed if the ODR is
192 * set but the buffer is not enabled yet.
193 *
194 * Note: iio_device_claim_buffer_mode() returns -EBUSY if the buffer
195 * is not enabled.
196 */
197 if (iio_device_claim_buffer_mode(indio_dev) < 0)
198 return 0;
199
200 out = (s16 *)st->samples;
201 for_each_set_bit(i,
202 indio_dev->active_scan_mask,
203 indio_dev->masklength) {
204 *out = data[i];
205 out++;
206 }
207
208 if (iio_device_get_clock(indio_dev) != CLOCK_BOOTTIME)
209 delta = iio_get_time_ns(indio_dev) - cros_ec_get_time_ns();
210 else
211 delta = 0;
212
213 iio_push_to_buffers_with_timestamp(indio_dev, st->samples,
214 timestamp + delta);
215
216 iio_device_release_buffer_mode(indio_dev);
217 return 0;
218 }
219 EXPORT_SYMBOL_GPL(cros_ec_sensors_push_data);
220
cros_ec_sensors_core_clean(void * arg)221 static void cros_ec_sensors_core_clean(void *arg)
222 {
223 struct platform_device *pdev = (struct platform_device *)arg;
224 struct cros_ec_sensorhub *sensor_hub =
225 dev_get_drvdata(pdev->dev.parent);
226 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
227 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
228 u8 sensor_num = st->param.info.sensor_num;
229
230 cros_ec_sensorhub_unregister_push_data(sensor_hub, sensor_num);
231 }
232
233 /**
234 * cros_ec_sensors_core_init() - basic initialization of the core structure
235 * @pdev: platform device created for the sensor
236 * @indio_dev: iio device structure of the device
237 * @physical_device: true if the device refers to a physical device
238 * @trigger_capture: function pointer to call buffer is triggered,
239 * for backward compatibility.
240 *
241 * Return: 0 on success, -errno on failure.
242 */
cros_ec_sensors_core_init(struct platform_device * pdev,struct iio_dev * indio_dev,bool physical_device,cros_ec_sensors_capture_t trigger_capture)243 int cros_ec_sensors_core_init(struct platform_device *pdev,
244 struct iio_dev *indio_dev,
245 bool physical_device,
246 cros_ec_sensors_capture_t trigger_capture)
247 {
248 struct device *dev = &pdev->dev;
249 struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
250 struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(dev->parent);
251 struct cros_ec_dev *ec = sensor_hub->ec;
252 struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
253 u32 ver_mask, temp;
254 int frequencies[ARRAY_SIZE(state->frequencies) / 2] = { 0 };
255 int ret, i;
256
257 platform_set_drvdata(pdev, indio_dev);
258
259 state->ec = ec->ec_dev;
260 state->msg = devm_kzalloc(&pdev->dev, sizeof(*state->msg) +
261 max((u16)sizeof(struct ec_params_motion_sense),
262 state->ec->max_response), GFP_KERNEL);
263 if (!state->msg)
264 return -ENOMEM;
265
266 state->resp = (struct ec_response_motion_sense *)state->msg->data;
267
268 mutex_init(&state->cmd_lock);
269
270 ret = cros_ec_get_host_cmd_version_mask(state->ec,
271 ec->cmd_offset,
272 EC_CMD_MOTION_SENSE_CMD,
273 &ver_mask);
274 if (ret < 0)
275 return ret;
276
277 /* Set up the host command structure. */
278 state->msg->version = fls(ver_mask) - 1;
279 state->msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
280 state->msg->outsize = sizeof(struct ec_params_motion_sense);
281
282 indio_dev->name = pdev->name;
283
284 if (physical_device) {
285 enum motionsensor_location loc;
286
287 state->param.cmd = MOTIONSENSE_CMD_INFO;
288 state->param.info.sensor_num = sensor_platform->sensor_num;
289 ret = cros_ec_motion_send_host_cmd(state, 0);
290 if (ret) {
291 dev_warn(dev, "Can not access sensor info\n");
292 return ret;
293 }
294 state->type = state->resp->info.type;
295 loc = state->resp->info.location;
296 if (loc == MOTIONSENSE_LOC_BASE)
297 indio_dev->label = "accel-base";
298 else if (loc == MOTIONSENSE_LOC_LID)
299 indio_dev->label = "accel-display";
300 else if (loc == MOTIONSENSE_LOC_CAMERA)
301 indio_dev->label = "accel-camera";
302
303 /* Set sign vector, only used for backward compatibility. */
304 memset(state->sign, 1, CROS_EC_SENSOR_MAX_AXIS);
305
306 for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++)
307 state->calib[i].scale = MOTION_SENSE_DEFAULT_SCALE;
308
309 /* 0 is a correct value used to stop the device */
310 if (state->msg->version < 3) {
311 get_default_min_max_freq(state->resp->info.type,
312 &frequencies[1],
313 &frequencies[2],
314 &state->fifo_max_event_count);
315 } else {
316 if (state->resp->info_3.max_frequency == 0) {
317 get_default_min_max_freq(state->resp->info.type,
318 &frequencies[1],
319 &frequencies[2],
320 &temp);
321 } else {
322 frequencies[1] = state->resp->info_3.min_frequency;
323 frequencies[2] = state->resp->info_3.max_frequency;
324 }
325 state->fifo_max_event_count = state->resp->info_3.fifo_max_event_count;
326 }
327 for (i = 0; i < ARRAY_SIZE(frequencies); i++) {
328 state->frequencies[2 * i] = frequencies[i] / 1000;
329 state->frequencies[2 * i + 1] =
330 (frequencies[i] % 1000) * 1000;
331 }
332
333 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
334 /*
335 * Create a software buffer, feed by the EC FIFO.
336 * We can not use trigger here, as events are generated
337 * as soon as sample_frequency is set.
338 */
339 ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev, NULL,
340 cros_ec_sensor_fifo_attributes);
341 if (ret)
342 return ret;
343
344 /* Timestamp coming from FIFO are in ns since boot. */
345 ret = iio_device_set_clock(indio_dev, CLOCK_BOOTTIME);
346 if (ret)
347 return ret;
348
349 } else {
350 /*
351 * The only way to get samples in buffer is to set a
352 * software trigger (systrig, hrtimer).
353 */
354 ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
355 NULL, trigger_capture, NULL);
356 if (ret)
357 return ret;
358 }
359 }
360
361 return 0;
362 }
363 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_init);
364
365 /**
366 * cros_ec_sensors_core_register() - Register callback to FIFO and IIO when
367 * sensor is ready.
368 * It must be called at the end of the sensor probe routine.
369 * @dev: device created for the sensor
370 * @indio_dev: iio device structure of the device
371 * @push_data: function to call when cros_ec_sensorhub receives
372 * a sample for that sensor.
373 *
374 * Return: 0 on success, -errno on failure.
375 */
cros_ec_sensors_core_register(struct device * dev,struct iio_dev * indio_dev,cros_ec_sensorhub_push_data_cb_t push_data)376 int cros_ec_sensors_core_register(struct device *dev,
377 struct iio_dev *indio_dev,
378 cros_ec_sensorhub_push_data_cb_t push_data)
379 {
380 struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
381 struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(dev->parent);
382 struct platform_device *pdev = to_platform_device(dev);
383 struct cros_ec_dev *ec = sensor_hub->ec;
384 int ret;
385
386 ret = devm_iio_device_register(dev, indio_dev);
387 if (ret)
388 return ret;
389
390 if (!push_data ||
391 !cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
392 return 0;
393
394 ret = cros_ec_sensorhub_register_push_data(
395 sensor_hub, sensor_platform->sensor_num,
396 indio_dev, push_data);
397 if (ret)
398 return ret;
399
400 return devm_add_action_or_reset(
401 dev, cros_ec_sensors_core_clean, pdev);
402 }
403 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_register);
404
405 /**
406 * cros_ec_motion_send_host_cmd() - send motion sense host command
407 * @state: pointer to state information for device
408 * @opt_length: optional length to reduce the response size, useful on the data
409 * path. Otherwise, the maximal allowed response size is used
410 *
411 * When called, the sub-command is assumed to be set in param->cmd.
412 *
413 * Return: 0 on success, -errno on failure.
414 */
cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state * state,u16 opt_length)415 int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *state,
416 u16 opt_length)
417 {
418 int ret;
419
420 if (opt_length)
421 state->msg->insize = min(opt_length, state->ec->max_response);
422 else
423 state->msg->insize = state->ec->max_response;
424
425 memcpy(state->msg->data, &state->param, sizeof(state->param));
426
427 ret = cros_ec_cmd_xfer_status(state->ec, state->msg);
428 if (ret < 0)
429 return ret;
430
431 if (ret &&
432 state->resp != (struct ec_response_motion_sense *)state->msg->data)
433 memcpy(state->resp, state->msg->data, ret);
434
435 return 0;
436 }
437 EXPORT_SYMBOL_GPL(cros_ec_motion_send_host_cmd);
438
cros_ec_sensors_calibrate(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)439 static ssize_t cros_ec_sensors_calibrate(struct iio_dev *indio_dev,
440 uintptr_t private, const struct iio_chan_spec *chan,
441 const char *buf, size_t len)
442 {
443 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
444 int ret, i;
445 bool calibrate;
446
447 ret = kstrtobool(buf, &calibrate);
448 if (ret < 0)
449 return ret;
450 if (!calibrate)
451 return -EINVAL;
452
453 mutex_lock(&st->cmd_lock);
454 st->param.cmd = MOTIONSENSE_CMD_PERFORM_CALIB;
455 ret = cros_ec_motion_send_host_cmd(st, 0);
456 if (ret != 0) {
457 dev_warn(&indio_dev->dev, "Unable to calibrate sensor\n");
458 } else {
459 /* Save values */
460 for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++)
461 st->calib[i].offset = st->resp->perform_calib.offset[i];
462 }
463 mutex_unlock(&st->cmd_lock);
464
465 return ret ? ret : len;
466 }
467
cros_ec_sensors_id(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)468 static ssize_t cros_ec_sensors_id(struct iio_dev *indio_dev,
469 uintptr_t private,
470 const struct iio_chan_spec *chan, char *buf)
471 {
472 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
473
474 return snprintf(buf, PAGE_SIZE, "%d\n", st->param.info.sensor_num);
475 }
476
477 const struct iio_chan_spec_ext_info cros_ec_sensors_ext_info[] = {
478 {
479 .name = "calibrate",
480 .shared = IIO_SHARED_BY_ALL,
481 .write = cros_ec_sensors_calibrate
482 },
483 {
484 .name = "id",
485 .shared = IIO_SHARED_BY_ALL,
486 .read = cros_ec_sensors_id
487 },
488 { },
489 };
490 EXPORT_SYMBOL_GPL(cros_ec_sensors_ext_info);
491
492 /**
493 * cros_ec_sensors_idx_to_reg - convert index into offset in shared memory
494 * @st: pointer to state information for device
495 * @idx: sensor index (should be element of enum sensor_index)
496 *
497 * Return: address to read at
498 */
cros_ec_sensors_idx_to_reg(struct cros_ec_sensors_core_state * st,unsigned int idx)499 static unsigned int cros_ec_sensors_idx_to_reg(
500 struct cros_ec_sensors_core_state *st,
501 unsigned int idx)
502 {
503 /*
504 * When using LPC interface, only space for 2 Accel and one Gyro.
505 * First halfword of MOTIONSENSE_TYPE_ACCEL is used by angle.
506 */
507 if (st->type == MOTIONSENSE_TYPE_ACCEL)
508 return EC_MEMMAP_ACC_DATA + sizeof(u16) *
509 (1 + idx + st->param.info.sensor_num *
510 CROS_EC_SENSOR_MAX_AXIS);
511
512 return EC_MEMMAP_GYRO_DATA + sizeof(u16) * idx;
513 }
514
cros_ec_sensors_cmd_read_u8(struct cros_ec_device * ec,unsigned int offset,u8 * dest)515 static int cros_ec_sensors_cmd_read_u8(struct cros_ec_device *ec,
516 unsigned int offset, u8 *dest)
517 {
518 return ec->cmd_readmem(ec, offset, 1, dest);
519 }
520
cros_ec_sensors_cmd_read_u16(struct cros_ec_device * ec,unsigned int offset,u16 * dest)521 static int cros_ec_sensors_cmd_read_u16(struct cros_ec_device *ec,
522 unsigned int offset, u16 *dest)
523 {
524 __le16 tmp;
525 int ret = ec->cmd_readmem(ec, offset, 2, &tmp);
526
527 if (ret >= 0)
528 *dest = le16_to_cpu(tmp);
529
530 return ret;
531 }
532
533 /**
534 * cros_ec_sensors_read_until_not_busy() - read until is not busy
535 *
536 * @st: pointer to state information for device
537 *
538 * Read from EC status byte until it reads not busy.
539 * Return: 8-bit status if ok, -errno on failure.
540 */
cros_ec_sensors_read_until_not_busy(struct cros_ec_sensors_core_state * st)541 static int cros_ec_sensors_read_until_not_busy(
542 struct cros_ec_sensors_core_state *st)
543 {
544 struct cros_ec_device *ec = st->ec;
545 u8 status;
546 int ret, attempts = 0;
547
548 ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
549 if (ret < 0)
550 return ret;
551
552 while (status & EC_MEMMAP_ACC_STATUS_BUSY_BIT) {
553 /* Give up after enough attempts, return error. */
554 if (attempts++ >= 50)
555 return -EIO;
556
557 /* Small delay every so often. */
558 if (attempts % 5 == 0)
559 msleep(25);
560
561 ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS,
562 &status);
563 if (ret < 0)
564 return ret;
565 }
566
567 return status;
568 }
569
570 /**
571 * cros_ec_sensors_read_data_unsafe() - read acceleration data from EC shared memory
572 * @indio_dev: pointer to IIO device
573 * @scan_mask: bitmap of the sensor indices to scan
574 * @data: location to store data
575 *
576 * This is the unsafe function for reading the EC data. It does not guarantee
577 * that the EC will not modify the data as it is being read in.
578 *
579 * Return: 0 on success, -errno on failure.
580 */
cros_ec_sensors_read_data_unsafe(struct iio_dev * indio_dev,unsigned long scan_mask,s16 * data)581 static int cros_ec_sensors_read_data_unsafe(struct iio_dev *indio_dev,
582 unsigned long scan_mask, s16 *data)
583 {
584 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
585 struct cros_ec_device *ec = st->ec;
586 unsigned int i;
587 int ret;
588
589 /* Read all sensors enabled in scan_mask. Each value is 2 bytes. */
590 for_each_set_bit(i, &scan_mask, indio_dev->masklength) {
591 ret = cros_ec_sensors_cmd_read_u16(ec,
592 cros_ec_sensors_idx_to_reg(st, i),
593 data);
594 if (ret < 0)
595 return ret;
596
597 *data *= st->sign[i];
598 data++;
599 }
600
601 return 0;
602 }
603
604 /**
605 * cros_ec_sensors_read_lpc() - read acceleration data from EC shared memory.
606 * @indio_dev: pointer to IIO device.
607 * @scan_mask: bitmap of the sensor indices to scan.
608 * @data: location to store data.
609 *
610 * Note: this is the safe function for reading the EC data. It guarantees
611 * that the data sampled was not modified by the EC while being read.
612 *
613 * Return: 0 on success, -errno on failure.
614 */
cros_ec_sensors_read_lpc(struct iio_dev * indio_dev,unsigned long scan_mask,s16 * data)615 int cros_ec_sensors_read_lpc(struct iio_dev *indio_dev,
616 unsigned long scan_mask, s16 *data)
617 {
618 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
619 struct cros_ec_device *ec = st->ec;
620 u8 samp_id = 0xff, status = 0;
621 int ret, attempts = 0;
622
623 /*
624 * Continually read all data from EC until the status byte after
625 * all reads reflects that the EC is not busy and the sample id
626 * matches the sample id from before all reads. This guarantees
627 * that data read in was not modified by the EC while reading.
628 */
629 while ((status & (EC_MEMMAP_ACC_STATUS_BUSY_BIT |
630 EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK)) != samp_id) {
631 /* If we have tried to read too many times, return error. */
632 if (attempts++ >= 5)
633 return -EIO;
634
635 /* Read status byte until EC is not busy. */
636 ret = cros_ec_sensors_read_until_not_busy(st);
637 if (ret < 0)
638 return ret;
639
640 /*
641 * Store the current sample id so that we can compare to the
642 * sample id after reading the data.
643 */
644 samp_id = ret & EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK;
645
646 /* Read all EC data, format it, and store it into data. */
647 ret = cros_ec_sensors_read_data_unsafe(indio_dev, scan_mask,
648 data);
649 if (ret < 0)
650 return ret;
651
652 /* Read status byte. */
653 ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS,
654 &status);
655 if (ret < 0)
656 return ret;
657 }
658
659 return 0;
660 }
661 EXPORT_SYMBOL_GPL(cros_ec_sensors_read_lpc);
662
663 /**
664 * cros_ec_sensors_read_cmd() - retrieve data using the EC command protocol
665 * @indio_dev: pointer to IIO device
666 * @scan_mask: bitmap of the sensor indices to scan
667 * @data: location to store data
668 *
669 * Return: 0 on success, -errno on failure.
670 */
cros_ec_sensors_read_cmd(struct iio_dev * indio_dev,unsigned long scan_mask,s16 * data)671 int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev,
672 unsigned long scan_mask, s16 *data)
673 {
674 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
675 int ret;
676 unsigned int i;
677
678 /* Read all sensor data through a command. */
679 st->param.cmd = MOTIONSENSE_CMD_DATA;
680 ret = cros_ec_motion_send_host_cmd(st, sizeof(st->resp->data));
681 if (ret != 0) {
682 dev_warn(&indio_dev->dev, "Unable to read sensor data\n");
683 return ret;
684 }
685
686 for_each_set_bit(i, &scan_mask, indio_dev->masklength) {
687 *data = st->resp->data.data[i];
688 data++;
689 }
690
691 return 0;
692 }
693 EXPORT_SYMBOL_GPL(cros_ec_sensors_read_cmd);
694
695 /**
696 * cros_ec_sensors_capture() - the trigger handler function
697 * @irq: the interrupt number.
698 * @p: a pointer to the poll function.
699 *
700 * On a trigger event occurring, if the pollfunc is attached then this
701 * handler is called as a threaded interrupt (and hence may sleep). It
702 * is responsible for grabbing data from the device and pushing it into
703 * the associated buffer.
704 *
705 * Return: IRQ_HANDLED
706 */
cros_ec_sensors_capture(int irq,void * p)707 irqreturn_t cros_ec_sensors_capture(int irq, void *p)
708 {
709 struct iio_poll_func *pf = p;
710 struct iio_dev *indio_dev = pf->indio_dev;
711 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
712 int ret;
713
714 mutex_lock(&st->cmd_lock);
715
716 /* Clear capture data. */
717 memset(st->samples, 0, indio_dev->scan_bytes);
718
719 /* Read data based on which channels are enabled in scan mask. */
720 ret = st->read_ec_sensors_data(indio_dev,
721 *(indio_dev->active_scan_mask),
722 (s16 *)st->samples);
723 if (ret < 0)
724 goto done;
725
726 iio_push_to_buffers_with_timestamp(indio_dev, st->samples,
727 iio_get_time_ns(indio_dev));
728
729 done:
730 /*
731 * Tell the core we are done with this trigger and ready for the
732 * next one.
733 */
734 iio_trigger_notify_done(indio_dev->trig);
735
736 mutex_unlock(&st->cmd_lock);
737
738 return IRQ_HANDLED;
739 }
740 EXPORT_SYMBOL_GPL(cros_ec_sensors_capture);
741
742 /**
743 * cros_ec_sensors_core_read() - function to request a value from the sensor
744 * @st: pointer to state information for device
745 * @chan: channel specification structure table
746 * @val: will contain one element making up the returned value
747 * @val2: will contain another element making up the returned value
748 * @mask: specifies which values to be requested
749 *
750 * Return: the type of value returned by the device
751 */
cros_ec_sensors_core_read(struct cros_ec_sensors_core_state * st,struct iio_chan_spec const * chan,int * val,int * val2,long mask)752 int cros_ec_sensors_core_read(struct cros_ec_sensors_core_state *st,
753 struct iio_chan_spec const *chan,
754 int *val, int *val2, long mask)
755 {
756 int ret, frequency;
757
758 switch (mask) {
759 case IIO_CHAN_INFO_SAMP_FREQ:
760 st->param.cmd = MOTIONSENSE_CMD_SENSOR_ODR;
761 st->param.sensor_odr.data =
762 EC_MOTION_SENSE_NO_VALUE;
763
764 ret = cros_ec_motion_send_host_cmd(st, 0);
765 if (ret)
766 break;
767
768 frequency = st->resp->sensor_odr.ret;
769 *val = frequency / 1000;
770 *val2 = (frequency % 1000) * 1000;
771 ret = IIO_VAL_INT_PLUS_MICRO;
772 break;
773 default:
774 ret = -EINVAL;
775 break;
776 }
777
778 return ret;
779 }
780 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_read);
781
782 /**
783 * cros_ec_sensors_core_read_avail() - get available values
784 * @indio_dev: pointer to state information for device
785 * @chan: channel specification structure table
786 * @vals: list of available values
787 * @type: type of data returned
788 * @length: number of data returned in the array
789 * @mask: specifies which values to be requested
790 *
791 * Return: an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST
792 */
cros_ec_sensors_core_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)793 int cros_ec_sensors_core_read_avail(struct iio_dev *indio_dev,
794 struct iio_chan_spec const *chan,
795 const int **vals,
796 int *type,
797 int *length,
798 long mask)
799 {
800 struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
801
802 switch (mask) {
803 case IIO_CHAN_INFO_SAMP_FREQ:
804 *length = ARRAY_SIZE(state->frequencies);
805 *vals = (const int *)&state->frequencies;
806 *type = IIO_VAL_INT_PLUS_MICRO;
807 return IIO_AVAIL_LIST;
808 }
809
810 return -EINVAL;
811 }
812 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_read_avail);
813
814 /**
815 * cros_ec_sensors_core_write() - function to write a value to the sensor
816 * @st: pointer to state information for device
817 * @chan: channel specification structure table
818 * @val: first part of value to write
819 * @val2: second part of value to write
820 * @mask: specifies which values to write
821 *
822 * Return: the type of value returned by the device
823 */
cros_ec_sensors_core_write(struct cros_ec_sensors_core_state * st,struct iio_chan_spec const * chan,int val,int val2,long mask)824 int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st,
825 struct iio_chan_spec const *chan,
826 int val, int val2, long mask)
827 {
828 int ret, frequency;
829
830 switch (mask) {
831 case IIO_CHAN_INFO_SAMP_FREQ:
832 frequency = val * 1000 + val2 / 1000;
833 st->param.cmd = MOTIONSENSE_CMD_SENSOR_ODR;
834 st->param.sensor_odr.data = frequency;
835
836 /* Always roundup, so caller gets at least what it asks for. */
837 st->param.sensor_odr.roundup = 1;
838
839 ret = cros_ec_motion_send_host_cmd(st, 0);
840 break;
841 default:
842 ret = -EINVAL;
843 break;
844 }
845 return ret;
846 }
847 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_write);
848
cros_ec_sensors_resume(struct device * dev)849 static int __maybe_unused cros_ec_sensors_resume(struct device *dev)
850 {
851 struct iio_dev *indio_dev = dev_get_drvdata(dev);
852 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
853 int ret = 0;
854
855 if (st->range_updated) {
856 mutex_lock(&st->cmd_lock);
857 st->param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
858 st->param.sensor_range.data = st->curr_range;
859 st->param.sensor_range.roundup = 1;
860 ret = cros_ec_motion_send_host_cmd(st, 0);
861 mutex_unlock(&st->cmd_lock);
862 }
863 return ret;
864 }
865
866 SIMPLE_DEV_PM_OPS(cros_ec_sensors_pm_ops, NULL, cros_ec_sensors_resume);
867 EXPORT_SYMBOL_GPL(cros_ec_sensors_pm_ops);
868
869 MODULE_DESCRIPTION("ChromeOS EC sensor hub core functions");
870 MODULE_LICENSE("GPL v2");
871