summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/iio/common/ssp_sensors/ssp_spi.c
blob: 704284a475aeca0218bbf83517d8479e4fbcd4e2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
/*
 *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 */

#include "ssp.h"

#define SSP_DEV (&data->spi->dev)
#define SSP_GET_MESSAGE_TYPE(data) (data & (3 << SSP_RW))

/*
 * SSP -> AP Instruction
 * They tell what packet type can be expected. In the future there will
 * be less of them. BYPASS means common sensor packets with accel, gyro,
 * hrm etc. data. LIBRARY and META are mock-up's for now.
 */
#define SSP_MSG2AP_INST_BYPASS_DATA		0x37
#define SSP_MSG2AP_INST_LIBRARY_DATA		0x01
#define SSP_MSG2AP_INST_DEBUG_DATA		0x03
#define SSP_MSG2AP_INST_BIG_DATA		0x04
#define SSP_MSG2AP_INST_META_DATA		0x05
#define SSP_MSG2AP_INST_TIME_SYNC		0x06
#define SSP_MSG2AP_INST_RESET			0x07

#define SSP_UNIMPLEMENTED -1

struct ssp_msg_header {
	u8 cmd;
	__le16 length;
	__le16 options;
	__le32 data;
} __attribute__((__packed__));

struct ssp_msg {
	u16 length;
	u16 options;
	struct list_head list;
	struct completion *done;
	struct ssp_msg_header *h;
	char *buffer;
};

static const int ssp_offset_map[SSP_SENSOR_MAX] = {
	[SSP_ACCELEROMETER_SENSOR] =		SSP_ACCELEROMETER_SIZE +
						SSP_TIME_SIZE,
	[SSP_GYROSCOPE_SENSOR] =		SSP_GYROSCOPE_SIZE +
						SSP_TIME_SIZE,
	[SSP_GEOMAGNETIC_UNCALIB_SENSOR] =	SSP_UNIMPLEMENTED,
	[SSP_GEOMAGNETIC_RAW] =			SSP_UNIMPLEMENTED,
	[SSP_GEOMAGNETIC_SENSOR] =		SSP_UNIMPLEMENTED,
	[SSP_PRESSURE_SENSOR] =			SSP_UNIMPLEMENTED,
	[SSP_GESTURE_SENSOR] =			SSP_UNIMPLEMENTED,
	[SSP_PROXIMITY_SENSOR] =		SSP_UNIMPLEMENTED,
	[SSP_TEMPERATURE_HUMIDITY_SENSOR] =	SSP_UNIMPLEMENTED,
	[SSP_LIGHT_SENSOR] =			SSP_UNIMPLEMENTED,
	[SSP_PROXIMITY_RAW] =			SSP_UNIMPLEMENTED,
	[SSP_ORIENTATION_SENSOR] =		SSP_UNIMPLEMENTED,
	[SSP_STEP_DETECTOR] =			SSP_UNIMPLEMENTED,
	[SSP_SIG_MOTION_SENSOR] =		SSP_UNIMPLEMENTED,
	[SSP_GYRO_UNCALIB_SENSOR] =		SSP_UNIMPLEMENTED,
	[SSP_GAME_ROTATION_VECTOR] =		SSP_UNIMPLEMENTED,
	[SSP_ROTATION_VECTOR] =			SSP_UNIMPLEMENTED,
	[SSP_STEP_COUNTER] =			SSP_UNIMPLEMENTED,
	[SSP_BIO_HRM_RAW] =			SSP_BIO_HRM_RAW_SIZE +
						SSP_TIME_SIZE,
	[SSP_BIO_HRM_RAW_FAC] =			SSP_BIO_HRM_RAW_FAC_SIZE +
						SSP_TIME_SIZE,
	[SSP_BIO_HRM_LIB] =			SSP_BIO_HRM_LIB_SIZE +
						SSP_TIME_SIZE,
};

#define SSP_HEADER_SIZE		(sizeof(struct ssp_msg_header))
#define SSP_HEADER_SIZE_ALIGNED	(ALIGN(SSP_HEADER_SIZE, 4))

static struct ssp_msg *ssp_create_msg(u8 cmd, u16 len, u16 opt, u32 data)
{
	struct ssp_msg_header h;
	struct ssp_msg *msg;

	msg = kzalloc(sizeof(*msg), GFP_KERNEL);
	if (!msg)
		return NULL;

	h.cmd = cmd;
	h.length = cpu_to_le16(len);
	h.options = cpu_to_le16(opt);
	h.data = cpu_to_le32(data);

	msg->buffer = kzalloc(SSP_HEADER_SIZE_ALIGNED + len,
			      GFP_KERNEL | GFP_DMA);
	if (!msg->buffer) {
		kfree(msg);
		return NULL;
	}

	msg->length = len;
	msg->options = opt;

	memcpy(msg->buffer, &h, SSP_HEADER_SIZE);

	return msg;
}

/*
 * It is a bit heavy to do it this way but often the function is used to compose
 * the message from smaller chunks which are placed on the stack.  Often the
 * chunks are small so memcpy should be optimalized.
 */
static inline void ssp_fill_buffer(struct ssp_msg *m, unsigned int offset,
				   const void *src, unsigned int len)
{
	memcpy(&m->buffer[SSP_HEADER_SIZE_ALIGNED + offset], src, len);
}

static inline void ssp_get_buffer(struct ssp_msg *m, unsigned int offset,
				  void *dest, unsigned int len)
{
	memcpy(dest, &m->buffer[SSP_HEADER_SIZE_ALIGNED + offset],  len);
}

#define SSP_GET_BUFFER_AT_INDEX(m, index) \
	(m->buffer[SSP_HEADER_SIZE_ALIGNED + index])
#define SSP_SET_BUFFER_AT_INDEX(m, index, val) \
	(m->buffer[SSP_HEADER_SIZE_ALIGNED + index] = val)

static void ssp_clean_msg(struct ssp_msg *m)
{
	kfree(m->buffer);
	kfree(m);
}

static int ssp_print_mcu_debug(char *data_frame, int *data_index,
			       int received_len)
{
	int length = data_frame[(*data_index)++];

	if (length > received_len - *data_index || length <= 0) {
		ssp_dbg("[SSP]: MSG From MCU-invalid debug length(%d/%d)\n",
			length, received_len);
		return length ? length : -EPROTO;
	}

	ssp_dbg("[SSP]: MSG From MCU - %s\n", &data_frame[*data_index]);

	*data_index += length;

	return 0;
}

/*
 * It was designed that way - additional lines to some kind of handshake,
 * please do not ask why - only the firmware guy can know it.
 */
static int ssp_check_lines(struct ssp_data *data, bool state)
{
	int delay_cnt = 0;

	gpio_set_value_cansleep(data->ap_mcu_gpio, state);

	while (gpio_get_value_cansleep(data->mcu_ap_gpio) != state) {
		usleep_range(3000, 3500);

		if (data->shut_down || delay_cnt++ > 500) {
			dev_err(SSP_DEV, "%s:timeout, hw ack wait fail %d\n",
				__func__, state);

			if (!state)
				gpio_set_value_cansleep(data->ap_mcu_gpio, 1);

			return -ETIMEDOUT;
		}
	}

	return 0;
}

static int ssp_do_transfer(struct ssp_data *data, struct ssp_msg *msg,
			   struct completion *done, int timeout)
{
	int status;
	/*
	 * check if this is a short one way message or the whole transfer has
	 * second part after an interrupt
	 */
	const bool use_no_irq = msg->length == 0;

	if (data->shut_down)
		return -EPERM;

	msg->done = done;

	mutex_lock(&data->comm_lock);

	status = ssp_check_lines(data, false);
	if (status < 0)
		goto _error_locked;

	status = spi_write(data->spi, msg->buffer, SSP_HEADER_SIZE);
	if (status < 0) {
		gpio_set_value_cansleep(data->ap_mcu_gpio, 1);
		dev_err(SSP_DEV, "%s spi_write fail\n", __func__);
		goto _error_locked;
	}

	if (!use_no_irq) {
		mutex_lock(&data->pending_lock);
		list_add_tail(&msg->list, &data->pending_list);
		mutex_unlock(&data->pending_lock);
	}

	status = ssp_check_lines(data, true);
	if (status < 0) {
		if (!use_no_irq) {
			mutex_lock(&data->pending_lock);
			list_del(&msg->list);
			mutex_unlock(&data->pending_lock);
		}
		goto _error_locked;
	}

	mutex_unlock(&data->comm_lock);

	if (!use_no_irq && done)
		if (wait_for_completion_timeout(done,
						msecs_to_jiffies(timeout)) ==
		    0) {
			mutex_lock(&data->pending_lock);
			list_del(&msg->list);
			mutex_unlock(&data->pending_lock);

			data->timeout_cnt++;
			return -ETIMEDOUT;
		}

	return 0;

_error_locked:
	mutex_unlock(&data->comm_lock);
	data->timeout_cnt++;
	return status;
}

static inline int ssp_spi_sync_command(struct ssp_data *data,
				       struct ssp_msg *msg)
{
	return ssp_do_transfer(data, msg, NULL, 0);
}

static int ssp_spi_sync(struct ssp_data *data, struct ssp_msg *msg,
			int timeout)
{
	DECLARE_COMPLETION_ONSTACK(done);

	if (WARN_ON(!msg->length))
		return -EPERM;

	return ssp_do_transfer(data, msg, &done, timeout);
}

static int ssp_handle_big_data(struct ssp_data *data, char *dataframe, int *idx)
{
	/* mock-up, it will be changed with adding another sensor types */
	*idx += 8;
	return 0;
}

static int ssp_parse_dataframe(struct ssp_data *data, char *dataframe, int len)
{
	int idx, sd;
	struct timespec ts;
	struct ssp_sensor_data *spd;
	struct iio_dev **indio_devs = data->sensor_devs;

	getnstimeofday(&ts);

	for (idx = 0; idx < len;) {
		switch (dataframe[idx++]) {
		case SSP_MSG2AP_INST_BYPASS_DATA:
			sd = dataframe[idx++];
			if (sd < 0 || sd >= SSP_SENSOR_MAX) {
				dev_err(SSP_DEV,
					"Mcu data frame1 error %d\n", sd);
				return -EPROTO;
			}

			if (indio_devs[sd]) {
				spd = iio_priv(indio_devs[sd]);
				if (spd->process_data)
					spd->process_data(indio_devs[sd],
							  &dataframe[idx],
							  data->timestamp);
			} else {
				dev_err(SSP_DEV, "no client for frame\n");
			}

			idx += ssp_offset_map[sd];
			break;
		case SSP_MSG2AP_INST_DEBUG_DATA:
			sd = ssp_print_mcu_debug(dataframe, &idx, len);
			if (sd) {
				dev_err(SSP_DEV,
					"Mcu data frame3 error %d\n", sd);
				return sd;
			}
			break;
		case SSP_MSG2AP_INST_LIBRARY_DATA:
			idx += len;
			break;
		case SSP_MSG2AP_INST_BIG_DATA:
			ssp_handle_big_data(data, dataframe, &idx);
			break;
		case SSP_MSG2AP_INST_TIME_SYNC:
			data->time_syncing = true;
			break;
		case SSP_MSG2AP_INST_RESET:
			ssp_queue_ssp_refresh_task(data, 0);
			break;
		}
	}

	if (data->time_syncing)
		data->timestamp = ts.tv_sec * 1000000000ULL + ts.tv_nsec;

	return 0;
}

/* threaded irq */
int ssp_irq_msg(struct ssp_data *data)
{
	bool found = false;
	char *buffer;
	u8 msg_type;
	int ret;
	u16 length, msg_options;
	struct ssp_msg *msg, *n;

	ret = spi_read(data->spi, data->header_buffer, SSP_HEADER_BUFFER_SIZE);
	if (ret < 0) {
		dev_err(SSP_DEV, "header read fail\n");
		return ret;
	}

	length = le16_to_cpu(data->header_buffer[1]);
	msg_options = le16_to_cpu(data->header_buffer[0]);

	if (length == 0) {
		dev_err(SSP_DEV, "length received from mcu is 0\n");
		return -EINVAL;
	}

	msg_type = SSP_GET_MESSAGE_TYPE(msg_options);

	switch (msg_type) {
	case SSP_AP2HUB_READ:
	case SSP_AP2HUB_WRITE:
		/*
		 * this is a small list, a few elements - the packets can be
		 * received with no order
		 */
		mutex_lock(&data->pending_lock);
		list_for_each_entry_safe(msg, n, &data->pending_list, list) {
			if (msg->options == msg_options) {
				list_del(&msg->list);
				found = true;
				break;
			}
		}

		if (!found) {
			/*
			 * here can be implemented dead messages handling
			 * but the slave should not send such ones - it is to
			 * check but let's handle this
			 */
			buffer = kmalloc(length, GFP_KERNEL | GFP_DMA);
			if (!buffer) {
				ret = -ENOMEM;
				goto _unlock;
			}

			/* got dead packet so it is always an error */
			ret = spi_read(data->spi, buffer, length);
			if (ret >= 0)
				ret = -EPROTO;

			kfree(buffer);

			dev_err(SSP_DEV, "No match error %x\n",
				msg_options);

			goto _unlock;
		}

		if (msg_type == SSP_AP2HUB_READ)
			ret = spi_read(data->spi,
				       &msg->buffer[SSP_HEADER_SIZE_ALIGNED],
				       msg->length);

		if (msg_type == SSP_AP2HUB_WRITE) {
			ret = spi_write(data->spi,
					&msg->buffer[SSP_HEADER_SIZE_ALIGNED],
					msg->length);
			if (msg_options & SSP_AP2HUB_RETURN) {
				msg->options =
					SSP_AP2HUB_READ | SSP_AP2HUB_RETURN;
				msg->length = 1;

				list_add_tail(&msg->list, &data->pending_list);
				goto _unlock;
			}
		}

		if (msg->done)
			if (!completion_done(msg->done))
				complete(msg->done);
_unlock:
		mutex_unlock(&data->pending_lock);
		break;
	case SSP_HUB2AP_WRITE:
		buffer = kzalloc(length, GFP_KERNEL | GFP_DMA);
		if (!buffer)
			return -ENOMEM;

		ret = spi_read(data->spi, buffer, length);
		if (ret < 0) {
			dev_err(SSP_DEV, "spi read fail\n");
			kfree(buffer);
			break;
		}

		ret = ssp_parse_dataframe(data, buffer, length);

		kfree(buffer);
		break;

	default:
		dev_err(SSP_DEV, "unknown msg type\n");
		return -EPROTO;
	}

	return ret;
}

void ssp_clean_pending_list(struct ssp_data *data)
{
	struct ssp_msg *msg, *n;

	mutex_lock(&data->pending_lock);
	list_for_each_entry_safe(msg, n, &data->pending_list, list) {
		list_del(&msg->list);

		if (msg->done)
			if (!completion_done(msg->done))
				complete(msg->done);
	}
	mutex_unlock(&data->pending_lock);
}

int ssp_command(struct ssp_data *data, char command, int arg)
{
	int ret;
	struct ssp_msg *msg;

	msg = ssp_create_msg(command, 0, SSP_AP2HUB_WRITE, arg);
	if (!msg)
		return -ENOMEM;

	ssp_dbg("%s - command 0x%x %d\n", __func__, command, arg);

	ret = ssp_spi_sync_command(data, msg);
	ssp_clean_msg(msg);

	return ret;
}

int ssp_send_instruction(struct ssp_data *data, u8 inst, u8 sensor_type,
			 u8 *send_buf, u8 length)
{
	int ret;
	struct ssp_msg *msg;

	if (data->fw_dl_state == SSP_FW_DL_STATE_DOWNLOADING) {
		dev_err(SSP_DEV, "%s - Skip Inst! DL state = %d\n",
			__func__, data->fw_dl_state);
		return -EBUSY;
	} else if (!(data->available_sensors & BIT(sensor_type)) &&
		   (inst <= SSP_MSG2SSP_INST_CHANGE_DELAY)) {
		dev_err(SSP_DEV, "%s - Bypass Inst Skip! - %u\n",
			__func__, sensor_type);
		return -EIO; /* just fail */
	}

	msg = ssp_create_msg(inst, length + 2, SSP_AP2HUB_WRITE, 0);
	if (!msg)
		return -ENOMEM;

	ssp_fill_buffer(msg, 0, &sensor_type, 1);
	ssp_fill_buffer(msg, 1, send_buf, length);

	ssp_dbg("%s - Inst = 0x%x, Sensor Type = 0x%x, data = %u\n",
		__func__, inst, sensor_type, send_buf[1]);

	ret = ssp_spi_sync(data, msg, 1000);
	ssp_clean_msg(msg);

	return ret;
}

int ssp_get_chipid(struct ssp_data *data)
{
	int ret;
	char buffer;
	struct ssp_msg *msg;

	msg = ssp_create_msg(SSP_MSG2SSP_AP_WHOAMI, 1, SSP_AP2HUB_READ, 0);
	if (!msg)
		return -ENOMEM;

	ret = ssp_spi_sync(data, msg, 1000);

	buffer = SSP_GET_BUFFER_AT_INDEX(msg, 0);

	ssp_clean_msg(msg);

	return ret < 0 ? ret : buffer;
}

int ssp_set_magnetic_matrix(struct ssp_data *data)
{
	int ret;
	struct ssp_msg *msg;

	msg = ssp_create_msg(SSP_MSG2SSP_AP_SET_MAGNETIC_STATIC_MATRIX,
			     data->sensorhub_info->mag_length, SSP_AP2HUB_WRITE,
			     0);
	if (!msg)
		return -ENOMEM;

	ssp_fill_buffer(msg, 0, data->sensorhub_info->mag_table,
			data->sensorhub_info->mag_length);

	ret = ssp_spi_sync(data, msg, 1000);
	ssp_clean_msg(msg);

	return ret;
}

unsigned int ssp_get_sensor_scanning_info(struct ssp_data *data)
{
	int ret;
	__le32 result;
	u32 cpu_result = 0;

	struct ssp_msg *msg = ssp_create_msg(SSP_MSG2SSP_AP_SENSOR_SCANNING, 4,
					     SSP_AP2HUB_READ, 0);
	if (!msg)
		return 0;

	ret = ssp_spi_sync(data, msg, 1000);
	if (ret < 0) {
		dev_err(SSP_DEV, "%s - spi read fail %d\n", __func__, ret);
		goto _exit;
	}

	ssp_get_buffer(msg, 0, &result, 4);
	cpu_result = le32_to_cpu(result);

	dev_info(SSP_DEV, "%s state: 0x%08x\n", __func__, cpu_result);

_exit:
	ssp_clean_msg(msg);
	return cpu_result;
}

unsigned int ssp_get_firmware_rev(struct ssp_data *data)
{
	int ret;
	__le32 result;

	struct ssp_msg *msg = ssp_create_msg(SSP_MSG2SSP_AP_FIRMWARE_REV, 4,
					     SSP_AP2HUB_READ, 0);
	if (!msg)
		return SSP_INVALID_REVISION;

	ret = ssp_spi_sync(data, msg, 1000);
	if (ret < 0) {
		dev_err(SSP_DEV, "%s - transfer fail %d\n", __func__, ret);
		ret = SSP_INVALID_REVISION;
		goto _exit;
	}

	ssp_get_buffer(msg, 0, &result, 4);
	ret = le32_to_cpu(result);

_exit:
	ssp_clean_msg(msg);
	return ret;
}