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