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