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 iio_for_each_active_channel(indio_dev, i) {
202 *out = data[i];
203 out++;
204 }
205
206 if (iio_device_get_clock(indio_dev) != CLOCK_BOOTTIME)
207 delta = iio_get_time_ns(indio_dev) - cros_ec_get_time_ns();
208 else
209 delta = 0;
210
211 iio_push_to_buffers_with_timestamp(indio_dev, st->samples,
212 timestamp + delta);
213
214 iio_device_release_buffer_mode(indio_dev);
215 return 0;
216 }
217 EXPORT_SYMBOL_GPL(cros_ec_sensors_push_data);
218
cros_ec_sensors_core_clean(void * arg)219 static void cros_ec_sensors_core_clean(void *arg)
220 {
221 struct platform_device *pdev = (struct platform_device *)arg;
222 struct cros_ec_sensorhub *sensor_hub =
223 dev_get_drvdata(pdev->dev.parent);
224 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
225 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
226 u8 sensor_num = st->param.info.sensor_num;
227
228 cros_ec_sensorhub_unregister_push_data(sensor_hub, sensor_num);
229 }
230
231 /**
232 * cros_ec_sensors_core_init() - basic initialization of the core structure
233 * @pdev: platform device created for the sensor
234 * @indio_dev: iio device structure of the device
235 * @physical_device: true if the device refers to a physical device
236 * @trigger_capture: function pointer to call buffer is triggered,
237 * for backward compatibility.
238 *
239 * Return: 0 on success, -errno on failure.
240 */
cros_ec_sensors_core_init(struct platform_device * pdev,struct iio_dev * indio_dev,bool physical_device,cros_ec_sensors_capture_t trigger_capture)241 int cros_ec_sensors_core_init(struct platform_device *pdev,
242 struct iio_dev *indio_dev,
243 bool physical_device,
244 cros_ec_sensors_capture_t trigger_capture)
245 {
246 struct device *dev = &pdev->dev;
247 struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
248 struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(dev->parent);
249 struct cros_ec_dev *ec = sensor_hub->ec;
250 struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
251 u32 ver_mask, temp;
252 int frequencies[ARRAY_SIZE(state->frequencies) / 2] = { 0 };
253 int ret, i;
254
255 platform_set_drvdata(pdev, indio_dev);
256
257 state->ec = ec->ec_dev;
258 state->msg = devm_kzalloc(&pdev->dev, sizeof(*state->msg) +
259 max((u16)sizeof(struct ec_params_motion_sense),
260 state->ec->max_response), GFP_KERNEL);
261 if (!state->msg)
262 return -ENOMEM;
263
264 state->resp = (struct ec_response_motion_sense *)state->msg->data;
265
266 mutex_init(&state->cmd_lock);
267
268 ret = cros_ec_get_host_cmd_version_mask(state->ec,
269 ec->cmd_offset,
270 EC_CMD_MOTION_SENSE_CMD,
271 &ver_mask);
272 if (ret < 0)
273 return ret;
274
275 /* Set up the host command structure. */
276 state->msg->version = fls(ver_mask) - 1;
277 state->msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
278 state->msg->outsize = sizeof(struct ec_params_motion_sense);
279
280 indio_dev->name = pdev->name;
281
282 if (physical_device) {
283 enum motionsensor_location loc;
284
285 state->param.cmd = MOTIONSENSE_CMD_INFO;
286 state->param.info.sensor_num = sensor_platform->sensor_num;
287 ret = cros_ec_motion_send_host_cmd(state, 0);
288 if (ret) {
289 dev_warn(dev, "Can not access sensor info\n");
290 return ret;
291 }
292 state->type = state->resp->info.type;
293 loc = state->resp->info.location;
294 if (loc == MOTIONSENSE_LOC_BASE)
295 indio_dev->label = "accel-base";
296 else if (loc == MOTIONSENSE_LOC_LID)
297 indio_dev->label = "accel-display";
298 else if (loc == MOTIONSENSE_LOC_CAMERA)
299 indio_dev->label = "accel-camera";
300
301 /* Set sign vector, only used for backward compatibility. */
302 memset(state->sign, 1, CROS_EC_SENSOR_MAX_AXIS);
303
304 for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++)
305 state->calib[i].scale = MOTION_SENSE_DEFAULT_SCALE;
306
307 /* 0 is a correct value used to stop the device */
308 if (state->msg->version < 3) {
309 get_default_min_max_freq(state->resp->info.type,
310 &frequencies[1],
311 &frequencies[2],
312 &state->fifo_max_event_count);
313 } else {
314 if (state->resp->info_3.max_frequency == 0) {
315 get_default_min_max_freq(state->resp->info.type,
316 &frequencies[1],
317 &frequencies[2],
318 &temp);
319 } else {
320 frequencies[1] = state->resp->info_3.min_frequency;
321 frequencies[2] = state->resp->info_3.max_frequency;
322 }
323 state->fifo_max_event_count = state->resp->info_3.fifo_max_event_count;
324 }
325 for (i = 0; i < ARRAY_SIZE(frequencies); i++) {
326 state->frequencies[2 * i] = frequencies[i] / 1000;
327 state->frequencies[2 * i + 1] =
328 (frequencies[i] % 1000) * 1000;
329 }
330
331 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
332 /*
333 * Create a software buffer, feed by the EC FIFO.
334 * We can not use trigger here, as events are generated
335 * as soon as sample_frequency is set.
336 */
337 ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev, NULL,
338 cros_ec_sensor_fifo_attributes);
339 if (ret)
340 return ret;
341
342 /* Timestamp coming from FIFO are in ns since boot. */
343 ret = iio_device_set_clock(indio_dev, CLOCK_BOOTTIME);
344 if (ret)
345 return ret;
346
347 } else {
348 /*
349 * The only way to get samples in buffer is to set a
350 * software trigger (systrig, hrtimer).
351 */
352 ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
353 NULL, trigger_capture, NULL);
354 if (ret)
355 return ret;
356 }
357 }
358
359 return 0;
360 }
361 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_init);
362
363 /**
364 * cros_ec_sensors_core_register() - Register callback to FIFO and IIO when
365 * sensor is ready.
366 * It must be called at the end of the sensor probe routine.
367 * @dev: device created for the sensor
368 * @indio_dev: iio device structure of the device
369 * @push_data: function to call when cros_ec_sensorhub receives
370 * a sample for that sensor.
371 *
372 * Return: 0 on success, -errno on failure.
373 */
cros_ec_sensors_core_register(struct device * dev,struct iio_dev * indio_dev,cros_ec_sensorhub_push_data_cb_t push_data)374 int cros_ec_sensors_core_register(struct device *dev,
375 struct iio_dev *indio_dev,
376 cros_ec_sensorhub_push_data_cb_t push_data)
377 {
378 struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
379 struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(dev->parent);
380 struct platform_device *pdev = to_platform_device(dev);
381 struct cros_ec_dev *ec = sensor_hub->ec;
382 int ret;
383
384 ret = devm_iio_device_register(dev, indio_dev);
385 if (ret)
386 return ret;
387
388 if (!push_data ||
389 !cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
390 return 0;
391
392 ret = cros_ec_sensorhub_register_push_data(
393 sensor_hub, sensor_platform->sensor_num,
394 indio_dev, push_data);
395 if (ret)
396 return ret;
397
398 return devm_add_action_or_reset(
399 dev, cros_ec_sensors_core_clean, pdev);
400 }
401 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_register);
402
403 /**
404 * cros_ec_motion_send_host_cmd() - send motion sense host command
405 * @state: pointer to state information for device
406 * @opt_length: optional length to reduce the response size, useful on the data
407 * path. Otherwise, the maximal allowed response size is used
408 *
409 * When called, the sub-command is assumed to be set in param->cmd.
410 *
411 * Return: 0 on success, -errno on failure.
412 */
cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state * state,u16 opt_length)413 int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *state,
414 u16 opt_length)
415 {
416 int ret;
417
418 if (opt_length)
419 state->msg->insize = min(opt_length, state->ec->max_response);
420 else
421 state->msg->insize = state->ec->max_response;
422
423 memcpy(state->msg->data, &state->param, sizeof(state->param));
424
425 ret = cros_ec_cmd_xfer_status(state->ec, state->msg);
426 if (ret < 0)
427 return ret;
428
429 if (ret &&
430 state->resp != (struct ec_response_motion_sense *)state->msg->data)
431 memcpy(state->resp, state->msg->data, ret);
432
433 return 0;
434 }
435 EXPORT_SYMBOL_GPL(cros_ec_motion_send_host_cmd);
436
cros_ec_sensors_calibrate(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)437 static ssize_t cros_ec_sensors_calibrate(struct iio_dev *indio_dev,
438 uintptr_t private, const struct iio_chan_spec *chan,
439 const char *buf, size_t len)
440 {
441 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
442 int ret, i;
443 bool calibrate;
444
445 ret = kstrtobool(buf, &calibrate);
446 if (ret < 0)
447 return ret;
448 if (!calibrate)
449 return -EINVAL;
450
451 mutex_lock(&st->cmd_lock);
452 st->param.cmd = MOTIONSENSE_CMD_PERFORM_CALIB;
453 ret = cros_ec_motion_send_host_cmd(st, 0);
454 if (ret != 0) {
455 dev_warn(&indio_dev->dev, "Unable to calibrate sensor\n");
456 } else {
457 /* Save values */
458 for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++)
459 st->calib[i].offset = st->resp->perform_calib.offset[i];
460 }
461 mutex_unlock(&st->cmd_lock);
462
463 return ret ? ret : len;
464 }
465
cros_ec_sensors_id(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)466 static ssize_t cros_ec_sensors_id(struct iio_dev *indio_dev,
467 uintptr_t private,
468 const struct iio_chan_spec *chan, char *buf)
469 {
470 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
471
472 return snprintf(buf, PAGE_SIZE, "%d\n", st->param.info.sensor_num);
473 }
474
475 const struct iio_chan_spec_ext_info cros_ec_sensors_ext_info[] = {
476 {
477 .name = "calibrate",
478 .shared = IIO_SHARED_BY_ALL,
479 .write = cros_ec_sensors_calibrate
480 },
481 {
482 .name = "id",
483 .shared = IIO_SHARED_BY_ALL,
484 .read = cros_ec_sensors_id
485 },
486 { },
487 };
488 EXPORT_SYMBOL_GPL(cros_ec_sensors_ext_info);
489
490 /**
491 * cros_ec_sensors_idx_to_reg - convert index into offset in shared memory
492 * @st: pointer to state information for device
493 * @idx: sensor index (should be element of enum sensor_index)
494 *
495 * Return: address to read at
496 */
cros_ec_sensors_idx_to_reg(struct cros_ec_sensors_core_state * st,unsigned int idx)497 static unsigned int cros_ec_sensors_idx_to_reg(
498 struct cros_ec_sensors_core_state *st,
499 unsigned int idx)
500 {
501 /*
502 * When using LPC interface, only space for 2 Accel and one Gyro.
503 * First halfword of MOTIONSENSE_TYPE_ACCEL is used by angle.
504 */
505 if (st->type == MOTIONSENSE_TYPE_ACCEL)
506 return EC_MEMMAP_ACC_DATA + sizeof(u16) *
507 (1 + idx + st->param.info.sensor_num *
508 CROS_EC_SENSOR_MAX_AXIS);
509
510 return EC_MEMMAP_GYRO_DATA + sizeof(u16) * idx;
511 }
512
cros_ec_sensors_cmd_read_u8(struct cros_ec_device * ec,unsigned int offset,u8 * dest)513 static int cros_ec_sensors_cmd_read_u8(struct cros_ec_device *ec,
514 unsigned int offset, u8 *dest)
515 {
516 return ec->cmd_readmem(ec, offset, 1, dest);
517 }
518
cros_ec_sensors_cmd_read_u16(struct cros_ec_device * ec,unsigned int offset,u16 * dest)519 static int cros_ec_sensors_cmd_read_u16(struct cros_ec_device *ec,
520 unsigned int offset, u16 *dest)
521 {
522 __le16 tmp;
523 int ret = ec->cmd_readmem(ec, offset, 2, &tmp);
524
525 if (ret >= 0)
526 *dest = le16_to_cpu(tmp);
527
528 return ret;
529 }
530
531 /**
532 * cros_ec_sensors_read_until_not_busy() - read until is not busy
533 *
534 * @st: pointer to state information for device
535 *
536 * Read from EC status byte until it reads not busy.
537 * Return: 8-bit status if ok, -errno on failure.
538 */
cros_ec_sensors_read_until_not_busy(struct cros_ec_sensors_core_state * st)539 static int cros_ec_sensors_read_until_not_busy(
540 struct cros_ec_sensors_core_state *st)
541 {
542 struct cros_ec_device *ec = st->ec;
543 u8 status;
544 int ret, attempts = 0;
545
546 ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
547 if (ret < 0)
548 return ret;
549
550 while (status & EC_MEMMAP_ACC_STATUS_BUSY_BIT) {
551 /* Give up after enough attempts, return error. */
552 if (attempts++ >= 50)
553 return -EIO;
554
555 /* Small delay every so often. */
556 if (attempts % 5 == 0)
557 msleep(25);
558
559 ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS,
560 &status);
561 if (ret < 0)
562 return ret;
563 }
564
565 return status;
566 }
567
568 /**
569 * cros_ec_sensors_read_data_unsafe() - read acceleration data from EC shared memory
570 * @indio_dev: pointer to IIO device
571 * @scan_mask: bitmap of the sensor indices to scan
572 * @data: location to store data
573 *
574 * This is the unsafe function for reading the EC data. It does not guarantee
575 * that the EC will not modify the data as it is being read in.
576 *
577 * Return: 0 on success, -errno on failure.
578 */
cros_ec_sensors_read_data_unsafe(struct iio_dev * indio_dev,unsigned long scan_mask,s16 * data)579 static int cros_ec_sensors_read_data_unsafe(struct iio_dev *indio_dev,
580 unsigned long scan_mask, s16 *data)
581 {
582 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
583 struct cros_ec_device *ec = st->ec;
584 unsigned int i;
585 int ret;
586
587 /* Read all sensors enabled in scan_mask. Each value is 2 bytes. */
588 for_each_set_bit(i, &scan_mask, iio_get_masklength(indio_dev)) {
589 ret = cros_ec_sensors_cmd_read_u16(ec,
590 cros_ec_sensors_idx_to_reg(st, i),
591 data);
592 if (ret < 0)
593 return ret;
594
595 *data *= st->sign[i];
596 data++;
597 }
598
599 return 0;
600 }
601
602 /**
603 * cros_ec_sensors_read_lpc() - read acceleration data from EC shared memory.
604 * @indio_dev: pointer to IIO device.
605 * @scan_mask: bitmap of the sensor indices to scan.
606 * @data: location to store data.
607 *
608 * Note: this is the safe function for reading the EC data. It guarantees
609 * that the data sampled was not modified by the EC while being read.
610 *
611 * Return: 0 on success, -errno on failure.
612 */
cros_ec_sensors_read_lpc(struct iio_dev * indio_dev,unsigned long scan_mask,s16 * data)613 int cros_ec_sensors_read_lpc(struct iio_dev *indio_dev,
614 unsigned long scan_mask, s16 *data)
615 {
616 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
617 struct cros_ec_device *ec = st->ec;
618 u8 samp_id = 0xff, status = 0;
619 int ret, attempts = 0;
620
621 /*
622 * Continually read all data from EC until the status byte after
623 * all reads reflects that the EC is not busy and the sample id
624 * matches the sample id from before all reads. This guarantees
625 * that data read in was not modified by the EC while reading.
626 */
627 while ((status & (EC_MEMMAP_ACC_STATUS_BUSY_BIT |
628 EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK)) != samp_id) {
629 /* If we have tried to read too many times, return error. */
630 if (attempts++ >= 5)
631 return -EIO;
632
633 /* Read status byte until EC is not busy. */
634 ret = cros_ec_sensors_read_until_not_busy(st);
635 if (ret < 0)
636 return ret;
637
638 /*
639 * Store the current sample id so that we can compare to the
640 * sample id after reading the data.
641 */
642 samp_id = ret & EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK;
643
644 /* Read all EC data, format it, and store it into data. */
645 ret = cros_ec_sensors_read_data_unsafe(indio_dev, scan_mask,
646 data);
647 if (ret < 0)
648 return ret;
649
650 /* Read status byte. */
651 ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS,
652 &status);
653 if (ret < 0)
654 return ret;
655 }
656
657 return 0;
658 }
659 EXPORT_SYMBOL_GPL(cros_ec_sensors_read_lpc);
660
661 /**
662 * cros_ec_sensors_read_cmd() - retrieve data using the EC command protocol
663 * @indio_dev: pointer to IIO device
664 * @scan_mask: bitmap of the sensor indices to scan
665 * @data: location to store data
666 *
667 * Return: 0 on success, -errno on failure.
668 */
cros_ec_sensors_read_cmd(struct iio_dev * indio_dev,unsigned long scan_mask,s16 * data)669 int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev,
670 unsigned long scan_mask, s16 *data)
671 {
672 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
673 int ret;
674 unsigned int i;
675
676 /* Read all sensor data through a command. */
677 st->param.cmd = MOTIONSENSE_CMD_DATA;
678 ret = cros_ec_motion_send_host_cmd(st, sizeof(st->resp->data));
679 if (ret != 0) {
680 dev_warn(&indio_dev->dev, "Unable to read sensor data\n");
681 return ret;
682 }
683
684 for_each_set_bit(i, &scan_mask, iio_get_masklength(indio_dev)) {
685 *data = st->resp->data.data[i];
686 data++;
687 }
688
689 return 0;
690 }
691 EXPORT_SYMBOL_GPL(cros_ec_sensors_read_cmd);
692
693 /**
694 * cros_ec_sensors_capture() - the trigger handler function
695 * @irq: the interrupt number.
696 * @p: a pointer to the poll function.
697 *
698 * On a trigger event occurring, if the pollfunc is attached then this
699 * handler is called as a threaded interrupt (and hence may sleep). It
700 * is responsible for grabbing data from the device and pushing it into
701 * the associated buffer.
702 *
703 * Return: IRQ_HANDLED
704 */
cros_ec_sensors_capture(int irq,void * p)705 irqreturn_t cros_ec_sensors_capture(int irq, void *p)
706 {
707 struct iio_poll_func *pf = p;
708 struct iio_dev *indio_dev = pf->indio_dev;
709 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
710 int ret;
711
712 mutex_lock(&st->cmd_lock);
713
714 /* Clear capture data. */
715 memset(st->samples, 0, indio_dev->scan_bytes);
716
717 /* Read data based on which channels are enabled in scan mask. */
718 ret = st->read_ec_sensors_data(indio_dev,
719 *(indio_dev->active_scan_mask),
720 (s16 *)st->samples);
721 if (ret < 0)
722 goto done;
723
724 iio_push_to_buffers_with_timestamp(indio_dev, st->samples,
725 iio_get_time_ns(indio_dev));
726
727 done:
728 /*
729 * Tell the core we are done with this trigger and ready for the
730 * next one.
731 */
732 iio_trigger_notify_done(indio_dev->trig);
733
734 mutex_unlock(&st->cmd_lock);
735
736 return IRQ_HANDLED;
737 }
738 EXPORT_SYMBOL_GPL(cros_ec_sensors_capture);
739
740 /**
741 * cros_ec_sensors_core_read() - function to request a value from the sensor
742 * @st: pointer to state information for device
743 * @chan: channel specification structure table
744 * @val: will contain one element making up the returned value
745 * @val2: will contain another element making up the returned value
746 * @mask: specifies which values to be requested
747 *
748 * Return: the type of value returned by the device
749 */
cros_ec_sensors_core_read(struct cros_ec_sensors_core_state * st,struct iio_chan_spec const * chan,int * val,int * val2,long mask)750 int cros_ec_sensors_core_read(struct cros_ec_sensors_core_state *st,
751 struct iio_chan_spec const *chan,
752 int *val, int *val2, long mask)
753 {
754 int ret, frequency;
755
756 switch (mask) {
757 case IIO_CHAN_INFO_SAMP_FREQ:
758 st->param.cmd = MOTIONSENSE_CMD_SENSOR_ODR;
759 st->param.sensor_odr.data =
760 EC_MOTION_SENSE_NO_VALUE;
761
762 ret = cros_ec_motion_send_host_cmd(st, 0);
763 if (ret)
764 break;
765
766 frequency = st->resp->sensor_odr.ret;
767 *val = frequency / 1000;
768 *val2 = (frequency % 1000) * 1000;
769 ret = IIO_VAL_INT_PLUS_MICRO;
770 break;
771 default:
772 ret = -EINVAL;
773 break;
774 }
775
776 return ret;
777 }
778 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_read);
779
780 /**
781 * cros_ec_sensors_core_read_avail() - get available values
782 * @indio_dev: pointer to state information for device
783 * @chan: channel specification structure table
784 * @vals: list of available values
785 * @type: type of data returned
786 * @length: number of data returned in the array
787 * @mask: specifies which values to be requested
788 *
789 * Return: an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST
790 */
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)791 int cros_ec_sensors_core_read_avail(struct iio_dev *indio_dev,
792 struct iio_chan_spec const *chan,
793 const int **vals,
794 int *type,
795 int *length,
796 long mask)
797 {
798 struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
799
800 switch (mask) {
801 case IIO_CHAN_INFO_SAMP_FREQ:
802 *length = ARRAY_SIZE(state->frequencies);
803 *vals = (const int *)&state->frequencies;
804 *type = IIO_VAL_INT_PLUS_MICRO;
805 return IIO_AVAIL_LIST;
806 }
807
808 return -EINVAL;
809 }
810 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_read_avail);
811
812 /**
813 * cros_ec_sensors_core_write() - function to write a value to the sensor
814 * @st: pointer to state information for device
815 * @chan: channel specification structure table
816 * @val: first part of value to write
817 * @val2: second part of value to write
818 * @mask: specifies which values to write
819 *
820 * Return: the type of value returned by the device
821 */
cros_ec_sensors_core_write(struct cros_ec_sensors_core_state * st,struct iio_chan_spec const * chan,int val,int val2,long mask)822 int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st,
823 struct iio_chan_spec const *chan,
824 int val, int val2, long mask)
825 {
826 int ret, frequency;
827
828 switch (mask) {
829 case IIO_CHAN_INFO_SAMP_FREQ:
830 frequency = val * 1000 + val2 / 1000;
831 st->param.cmd = MOTIONSENSE_CMD_SENSOR_ODR;
832 st->param.sensor_odr.data = frequency;
833
834 /* Always roundup, so caller gets at least what it asks for. */
835 st->param.sensor_odr.roundup = 1;
836
837 ret = cros_ec_motion_send_host_cmd(st, 0);
838 break;
839 default:
840 ret = -EINVAL;
841 break;
842 }
843 return ret;
844 }
845 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_write);
846
cros_ec_sensors_resume(struct device * dev)847 static int __maybe_unused cros_ec_sensors_resume(struct device *dev)
848 {
849 struct iio_dev *indio_dev = dev_get_drvdata(dev);
850 struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
851 int ret = 0;
852
853 if (st->range_updated) {
854 mutex_lock(&st->cmd_lock);
855 st->param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
856 st->param.sensor_range.data = st->curr_range;
857 st->param.sensor_range.roundup = 1;
858 ret = cros_ec_motion_send_host_cmd(st, 0);
859 mutex_unlock(&st->cmd_lock);
860 }
861 return ret;
862 }
863
864 SIMPLE_DEV_PM_OPS(cros_ec_sensors_pm_ops, NULL, cros_ec_sensors_resume);
865 EXPORT_SYMBOL_GPL(cros_ec_sensors_pm_ops);
866
867 MODULE_DESCRIPTION("ChromeOS EC sensor hub core functions");
868 MODULE_LICENSE("GPL v2");
869