summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/drm_mipi_dsi.c
blob: 2d5ca8eec13a9611668a90756a756f6f40a0506b (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
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
/*
 * MIPI DSI Bus
 *
 * Copyright (C) 2012-2013, Samsung Electronics, Co., Ltd.
 * Andrzej Hajda <a.hajda@samsung.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include <drm/drm_mipi_dsi.h>

#include <linux/device.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>

#include <video/mipi_display.h>

/**
 * DOC: dsi helpers
 *
 * These functions contain some common logic and helpers to deal with MIPI DSI
 * peripherals.
 *
 * Helpers are provided for a number of standard MIPI DSI command as well as a
 * subset of the MIPI DCS command set.
 */

static int mipi_dsi_device_match(struct device *dev, struct device_driver *drv)
{
	return of_driver_match_device(dev, drv);
}

static const struct dev_pm_ops mipi_dsi_device_pm_ops = {
	.runtime_suspend = pm_generic_runtime_suspend,
	.runtime_resume = pm_generic_runtime_resume,
	.suspend = pm_generic_suspend,
	.resume = pm_generic_resume,
	.freeze = pm_generic_freeze,
	.thaw = pm_generic_thaw,
	.poweroff = pm_generic_poweroff,
	.restore = pm_generic_restore,
};

static struct bus_type mipi_dsi_bus_type = {
	.name = "mipi-dsi",
	.match = mipi_dsi_device_match,
	.pm = &mipi_dsi_device_pm_ops,
};

static int of_device_match(struct device *dev, void *data)
{
	return dev->of_node == data;
}

/**
 * of_find_mipi_dsi_device_by_node() - find the MIPI DSI device matching a
 *    device tree node
 * @np: device tree node
 *
 * Return: A pointer to the MIPI DSI device corresponding to @np or NULL if no
 *    such device exists (or has not been registered yet).
 */
struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node *np)
{
	struct device *dev;

	dev = bus_find_device(&mipi_dsi_bus_type, NULL, np, of_device_match);

	return dev ? to_mipi_dsi_device(dev) : NULL;
}
EXPORT_SYMBOL(of_find_mipi_dsi_device_by_node);

static void mipi_dsi_dev_release(struct device *dev)
{
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);

	of_node_put(dev->of_node);
	kfree(dsi);
}

static const struct device_type mipi_dsi_device_type = {
	.release = mipi_dsi_dev_release,
};

static struct mipi_dsi_device *mipi_dsi_device_alloc(struct mipi_dsi_host *host)
{
	struct mipi_dsi_device *dsi;

	dsi = kzalloc(sizeof(*dsi), GFP_KERNEL);
	if (!dsi)
		return ERR_PTR(-ENOMEM);

	dsi->host = host;
	dsi->dev.bus = &mipi_dsi_bus_type;
	dsi->dev.parent = host->dev;
	dsi->dev.type = &mipi_dsi_device_type;

	device_initialize(&dsi->dev);

	return dsi;
}

static int mipi_dsi_device_add(struct mipi_dsi_device *dsi)
{
	struct mipi_dsi_host *host = dsi->host;

	dev_set_name(&dsi->dev, "%s.%d", dev_name(host->dev),  dsi->channel);

	return device_add(&dsi->dev);
}

static struct mipi_dsi_device *
of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
{
	struct mipi_dsi_device *dsi;
	struct device *dev = host->dev;
	int ret;
	u32 reg;

	ret = of_property_read_u32(node, "reg", &reg);
	if (ret) {
		dev_err(dev, "device node %s has no valid reg property: %d\n",
			node->full_name, ret);
		return ERR_PTR(-EINVAL);
	}

	if (reg > 3) {
		dev_err(dev, "device node %s has invalid reg property: %u\n",
			node->full_name, reg);
		return ERR_PTR(-EINVAL);
	}

	dsi = mipi_dsi_device_alloc(host);
	if (IS_ERR(dsi)) {
		dev_err(dev, "failed to allocate DSI device %s: %ld\n",
			node->full_name, PTR_ERR(dsi));
		return dsi;
	}

	dsi->dev.of_node = of_node_get(node);
	dsi->channel = reg;

	ret = mipi_dsi_device_add(dsi);
	if (ret) {
		dev_err(dev, "failed to add DSI device %s: %d\n",
			node->full_name, ret);
		kfree(dsi);
		return ERR_PTR(ret);
	}

	return dsi;
}

int mipi_dsi_host_register(struct mipi_dsi_host *host)
{
	struct device_node *node;

	for_each_available_child_of_node(host->dev->of_node, node) {
		/* skip nodes without reg property */
		if (!of_find_property(node, "reg", NULL))
			continue;
		of_mipi_dsi_device_add(host, node);
	}

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_host_register);

static int mipi_dsi_remove_device_fn(struct device *dev, void *priv)
{
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);

	device_unregister(&dsi->dev);

	return 0;
}

void mipi_dsi_host_unregister(struct mipi_dsi_host *host)
{
	device_for_each_child(host->dev, NULL, mipi_dsi_remove_device_fn);
}
EXPORT_SYMBOL(mipi_dsi_host_unregister);

/**
 * mipi_dsi_attach - attach a DSI device to its DSI host
 * @dsi: DSI peripheral
 */
int mipi_dsi_attach(struct mipi_dsi_device *dsi)
{
	const struct mipi_dsi_host_ops *ops = dsi->host->ops;

	if (!ops || !ops->attach)
		return -ENOSYS;

	return ops->attach(dsi->host, dsi);
}
EXPORT_SYMBOL(mipi_dsi_attach);

/**
 * mipi_dsi_detach - detach a DSI device from its DSI host
 * @dsi: DSI peripheral
 */
int mipi_dsi_detach(struct mipi_dsi_device *dsi)
{
	const struct mipi_dsi_host_ops *ops = dsi->host->ops;

	if (!ops || !ops->detach)
		return -ENOSYS;

	return ops->detach(dsi->host, dsi);
}
EXPORT_SYMBOL(mipi_dsi_detach);

static ssize_t mipi_dsi_device_transfer(struct mipi_dsi_device *dsi,
					struct mipi_dsi_msg *msg)
{
	const struct mipi_dsi_host_ops *ops = dsi->host->ops;

	if (!ops || !ops->transfer)
		return -ENOSYS;

	if (dsi->mode_flags & MIPI_DSI_MODE_LPM)
		msg->flags |= MIPI_DSI_MSG_USE_LPM;

	return ops->transfer(dsi->host, msg);
}

/**
 * mipi_dsi_packet_format_is_short - check if a packet is of the short format
 * @type: MIPI DSI data type of the packet
 *
 * Return: true if the packet for the given data type is a short packet, false
 * otherwise.
 */
bool mipi_dsi_packet_format_is_short(u8 type)
{
	switch (type) {
	case MIPI_DSI_V_SYNC_START:
	case MIPI_DSI_V_SYNC_END:
	case MIPI_DSI_H_SYNC_START:
	case MIPI_DSI_H_SYNC_END:
	case MIPI_DSI_END_OF_TRANSMISSION:
	case MIPI_DSI_COLOR_MODE_OFF:
	case MIPI_DSI_COLOR_MODE_ON:
	case MIPI_DSI_SHUTDOWN_PERIPHERAL:
	case MIPI_DSI_TURN_ON_PERIPHERAL:
	case MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM:
	case MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM:
	case MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM:
	case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM:
	case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM:
	case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM:
	case MIPI_DSI_DCS_SHORT_WRITE:
	case MIPI_DSI_DCS_SHORT_WRITE_PARAM:
	case MIPI_DSI_DCS_READ:
	case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
		return true;
	}

	return false;
}
EXPORT_SYMBOL(mipi_dsi_packet_format_is_short);

/**
 * mipi_dsi_packet_format_is_long - check if a packet is of the long format
 * @type: MIPI DSI data type of the packet
 *
 * Return: true if the packet for the given data type is a long packet, false
 * otherwise.
 */
bool mipi_dsi_packet_format_is_long(u8 type)
{
	switch (type) {
	case MIPI_DSI_NULL_PACKET:
	case MIPI_DSI_BLANKING_PACKET:
	case MIPI_DSI_GENERIC_LONG_WRITE:
	case MIPI_DSI_DCS_LONG_WRITE:
	case MIPI_DSI_LOOSELY_PACKED_PIXEL_STREAM_YCBCR20:
	case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR24:
	case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR16:
	case MIPI_DSI_PACKED_PIXEL_STREAM_30:
	case MIPI_DSI_PACKED_PIXEL_STREAM_36:
	case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR12:
	case MIPI_DSI_PACKED_PIXEL_STREAM_16:
	case MIPI_DSI_PACKED_PIXEL_STREAM_18:
	case MIPI_DSI_PIXEL_STREAM_3BYTE_18:
	case MIPI_DSI_PACKED_PIXEL_STREAM_24:
		return true;
	}

	return false;
}
EXPORT_SYMBOL(mipi_dsi_packet_format_is_long);

/**
 * mipi_dsi_create_packet - create a packet from a message according to the
 *     DSI protocol
 * @packet: pointer to a DSI packet structure
 * @msg: message to translate into a packet
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
			   const struct mipi_dsi_msg *msg)
{
	if (!packet || !msg)
		return -EINVAL;

	/* do some minimum sanity checking */
	if (!mipi_dsi_packet_format_is_short(msg->type) &&
	    !mipi_dsi_packet_format_is_long(msg->type))
		return -EINVAL;

	if (msg->channel > 3)
		return -EINVAL;

	memset(packet, 0, sizeof(*packet));
	packet->header[0] = ((msg->channel & 0x3) << 6) | (msg->type & 0x3f);

	/* TODO: compute ECC if hardware support is not available */

	/*
	 * Long write packets contain the word count in header bytes 1 and 2.
	 * The payload follows the header and is word count bytes long.
	 *
	 * Short write packets encode up to two parameters in header bytes 1
	 * and 2.
	 */
	if (mipi_dsi_packet_format_is_long(msg->type)) {
		packet->header[1] = (msg->tx_len >> 0) & 0xff;
		packet->header[2] = (msg->tx_len >> 8) & 0xff;

		packet->payload_length = msg->tx_len;
		packet->payload = msg->tx_buf;
	} else {
		const u8 *tx = msg->tx_buf;

		packet->header[1] = (msg->tx_len > 0) ? tx[0] : 0;
		packet->header[2] = (msg->tx_len > 1) ? tx[1] : 0;
	}

	packet->size = sizeof(packet->header) + packet->payload_length;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_create_packet);

/*
 * mipi_dsi_set_maximum_return_packet_size() - specify the maximum size of the
 *    the payload in a long packet transmitted from the peripheral back to the
 *    host processor
 * @dsi: DSI peripheral device
 * @value: the maximum size of the payload
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
					    u16 value)
{
	u8 tx[2] = { value & 0xff, value >> 8 };
	struct mipi_dsi_msg msg = {
		.channel = dsi->channel,
		.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE,
		.tx_len = sizeof(tx),
		.tx_buf = tx,
	};

	return mipi_dsi_device_transfer(dsi, &msg);
}
EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);

/**
 * mipi_dsi_generic_write() - transmit data using a generic write packet
 * @dsi: DSI peripheral device
 * @payload: buffer containing the payload
 * @size: size of payload buffer
 *
 * This function will automatically choose the right data type depending on
 * the payload length.
 *
 * Return: The number of bytes transmitted on success or a negative error code
 * on failure.
 */
ssize_t mipi_dsi_generic_write(struct mipi_dsi_device *dsi, const void *payload,
			       size_t size)
{
	struct mipi_dsi_msg msg = {
		.channel = dsi->channel,
		.tx_buf = payload,
		.tx_len = size
	};

	switch (size) {
	case 0:
		msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM;
		break;

	case 1:
		msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM;
		break;

	case 2:
		msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM;
		break;

	default:
		msg.type = MIPI_DSI_GENERIC_LONG_WRITE;
		break;
	}

	return mipi_dsi_device_transfer(dsi, &msg);
}
EXPORT_SYMBOL(mipi_dsi_generic_write);

/**
 * mipi_dsi_generic_read() - receive data using a generic read packet
 * @dsi: DSI peripheral device
 * @params: buffer containing the request parameters
 * @num_params: number of request parameters
 * @data: buffer in which to return the received data
 * @size: size of receive buffer
 *
 * This function will automatically choose the right data type depending on
 * the number of parameters passed in.
 *
 * Return: The number of bytes successfully read or a negative error code on
 * failure.
 */
ssize_t mipi_dsi_generic_read(struct mipi_dsi_device *dsi, const void *params,
			      size_t num_params, void *data, size_t size)
{
	struct mipi_dsi_msg msg = {
		.channel = dsi->channel,
		.tx_len = num_params,
		.tx_buf = params,
		.rx_len = size,
		.rx_buf = data
	};

	switch (num_params) {
	case 0:
		msg.type = MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM;
		break;

	case 1:
		msg.type = MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM;
		break;

	case 2:
		msg.type = MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM;
		break;

	default:
		return -EINVAL;
	}

	return mipi_dsi_device_transfer(dsi, &msg);
}
EXPORT_SYMBOL(mipi_dsi_generic_read);

/**
 * mipi_dsi_dcs_write_buffer() - transmit a DCS command with payload
 * @dsi: DSI peripheral device
 * @data: buffer containing data to be transmitted
 * @len: size of transmission buffer
 *
 * This function will automatically choose the right data type depending on
 * the command payload length.
 *
 * Return: The number of bytes successfully transmitted or a negative error
 * code on failure.
 */
ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi,
				  const void *data, size_t len)
{
	struct mipi_dsi_msg msg = {
		.channel = dsi->channel,
		.tx_buf = data,
		.tx_len = len
	};

	switch (len) {
	case 0:
		return -EINVAL;

	case 1:
		msg.type = MIPI_DSI_DCS_SHORT_WRITE;
		break;

	case 2:
		msg.type = MIPI_DSI_DCS_SHORT_WRITE_PARAM;
		break;

	default:
		msg.type = MIPI_DSI_DCS_LONG_WRITE;
		break;
	}

	return mipi_dsi_device_transfer(dsi, &msg);
}
EXPORT_SYMBOL(mipi_dsi_dcs_write_buffer);

/**
 * mipi_dsi_dcs_write() - send DCS write command
 * @dsi: DSI peripheral device
 * @cmd: DCS command
 * @data: buffer containing the command payload
 * @len: command payload length
 *
 * This function will automatically choose the right data type depending on
 * the command payload length.
 *
 * Return: The number of bytes successfully transmitted or a negative error
 * code on failure.
 */
ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, u8 cmd,
			   const void *data, size_t len)
{
	ssize_t err;
	size_t size;
	u8 *tx;

	if (len > 0) {
		size = 1 + len;

		tx = kmalloc(size, GFP_KERNEL);
		if (!tx)
			return -ENOMEM;

		/* concatenate the DCS command byte and the payload */
		tx[0] = cmd;
		memcpy(&tx[1], data, len);
	} else {
		tx = &cmd;
		size = 1;
	}

	err = mipi_dsi_dcs_write_buffer(dsi, tx, size);

	if (len > 0)
		kfree(tx);

	return err;
}
EXPORT_SYMBOL(mipi_dsi_dcs_write);

/**
 * mipi_dsi_dcs_read() - send DCS read request command
 * @dsi: DSI peripheral device
 * @cmd: DCS command
 * @data: buffer in which to receive data
 * @len: size of receive buffer
 *
 * Return: The number of bytes read or a negative error code on failure.
 */
ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,
			  size_t len)
{
	struct mipi_dsi_msg msg = {
		.channel = dsi->channel,
		.type = MIPI_DSI_DCS_READ,
		.tx_buf = &cmd,
		.tx_len = 1,
		.rx_buf = data,
		.rx_len = len
	};

	return mipi_dsi_device_transfer(dsi, &msg);
}
EXPORT_SYMBOL(mipi_dsi_dcs_read);

/**
 * mipi_dsi_dcs_nop() - send DCS nop packet
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_nop(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_NOP, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_nop);

/**
 * mipi_dsi_dcs_soft_reset() - perform a software reset of the display module
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_soft_reset(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SOFT_RESET, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_soft_reset);

/**
 * mipi_dsi_dcs_get_power_mode() - query the display module's current power
 *    mode
 * @dsi: DSI peripheral device
 * @mode: return location for the current power mode
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_get_power_mode(struct mipi_dsi_device *dsi, u8 *mode)
{
	ssize_t err;

	err = mipi_dsi_dcs_read(dsi, MIPI_DCS_GET_POWER_MODE, mode,
				sizeof(*mode));
	if (err <= 0) {
		if (err == 0)
			err = -ENODATA;

		return err;
	}

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_get_power_mode);

/**
 * mipi_dsi_dcs_get_pixel_format() - gets the pixel format for the RGB image
 *    data used by the interface
 * @dsi: DSI peripheral device
 * @format: return location for the pixel format
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_get_pixel_format(struct mipi_dsi_device *dsi, u8 *format)
{
	ssize_t err;

	err = mipi_dsi_dcs_read(dsi, MIPI_DCS_GET_PIXEL_FORMAT, format,
				sizeof(*format));
	if (err <= 0) {
		if (err == 0)
			err = -ENODATA;

		return err;
	}

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_get_pixel_format);

/**
 * mipi_dsi_dcs_enter_sleep_mode() - disable all unnecessary blocks inside the
 *    display module except interface communication
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_enter_sleep_mode(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_ENTER_SLEEP_MODE, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_enter_sleep_mode);

/**
 * mipi_dsi_dcs_exit_sleep_mode() - enable all blocks inside the display
 *    module
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_exit_sleep_mode(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_EXIT_SLEEP_MODE, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_exit_sleep_mode);

/**
 * mipi_dsi_dcs_set_display_off() - stop displaying the image data on the
 *    display device
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_set_display_off(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_OFF, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_display_off);

/**
 * mipi_dsi_dcs_set_display_on() - start displaying the image data on the
 *    display device
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure
 */
int mipi_dsi_dcs_set_display_on(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_ON, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_display_on);

/**
 * mipi_dsi_dcs_set_column_address() - define the column extent of the frame
 *    memory accessed by the host processor
 * @dsi: DSI peripheral device
 * @start: first column of frame memory
 * @end: last column of frame memory
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_set_column_address(struct mipi_dsi_device *dsi, u16 start,
				    u16 end)
{
	u8 payload[4] = { start >> 8, start & 0xff, end >> 8, end & 0xff };
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_COLUMN_ADDRESS, payload,
				 sizeof(payload));
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_column_address);

/**
 * mipi_dsi_dcs_set_page_address() - define the page extent of the frame
 *    memory accessed by the host processor
 * @dsi: DSI peripheral device
 * @start: first page of frame memory
 * @end: last page of frame memory
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_set_page_address(struct mipi_dsi_device *dsi, u16 start,
				  u16 end)
{
	u8 payload[4] = { start >> 8, start & 0xff, end >> 8, end & 0xff };
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_PAGE_ADDRESS, payload,
				 sizeof(payload));
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_page_address);

/**
 * mipi_dsi_dcs_set_tear_off() - turn off the display module's Tearing Effect
 *    output signal on the TE signal line
 * @dsi: DSI peripheral device
 *
 * Return: 0 on success or a negative error code on failure
 */
int mipi_dsi_dcs_set_tear_off(struct mipi_dsi_device *dsi)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_TEAR_OFF, NULL, 0);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_tear_off);

/**
 * mipi_dsi_dcs_set_tear_on() - turn on the display module's Tearing Effect
 *    output signal on the TE signal line.
 * @dsi: DSI peripheral device
 * @mode: the Tearing Effect Output Line mode
 *
 * Return: 0 on success or a negative error code on failure
 */
int mipi_dsi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
			     enum mipi_dsi_dcs_tear_mode mode)
{
	u8 value = mode;
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_TEAR_ON, &value,
				 sizeof(value));
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_tear_on);

/**
 * mipi_dsi_dcs_set_pixel_format() - sets the pixel format for the RGB image
 *    data used by the interface
 * @dsi: DSI peripheral device
 * @format: pixel format
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_dcs_set_pixel_format(struct mipi_dsi_device *dsi, u8 format)
{
	ssize_t err;

	err = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_PIXEL_FORMAT, &format,
				 sizeof(format));
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL(mipi_dsi_dcs_set_pixel_format);

static int mipi_dsi_drv_probe(struct device *dev)
{
	struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);

	return drv->probe(dsi);
}

static int mipi_dsi_drv_remove(struct device *dev)
{
	struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);

	return drv->remove(dsi);
}

static void mipi_dsi_drv_shutdown(struct device *dev)
{
	struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);

	drv->shutdown(dsi);
}

/**
 * mipi_dsi_driver_register_full() - register a driver for DSI devices
 * @drv: DSI driver structure
 * @owner: owner module
 *
 * Return: 0 on success or a negative error code on failure.
 */
int mipi_dsi_driver_register_full(struct mipi_dsi_driver *drv,
				  struct module *owner)
{
	drv->driver.bus = &mipi_dsi_bus_type;
	drv->driver.owner = owner;

	if (drv->probe)
		drv->driver.probe = mipi_dsi_drv_probe;
	if (drv->remove)
		drv->driver.remove = mipi_dsi_drv_remove;
	if (drv->shutdown)
		drv->driver.shutdown = mipi_dsi_drv_shutdown;

	return driver_register(&drv->driver);
}
EXPORT_SYMBOL(mipi_dsi_driver_register_full);

/**
 * mipi_dsi_driver_unregister() - unregister a driver for DSI devices
 * @drv: DSI driver structure
 *
 * Return: 0 on success or a negative error code on failure.
 */
void mipi_dsi_driver_unregister(struct mipi_dsi_driver *drv)
{
	driver_unregister(&drv->driver);
}
EXPORT_SYMBOL(mipi_dsi_driver_unregister);

static int __init mipi_dsi_bus_init(void)
{
	return bus_register(&mipi_dsi_bus_type);
}
postcore_initcall(mipi_dsi_bus_init);

MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
MODULE_DESCRIPTION("MIPI DSI Bus");
MODULE_LICENSE("GPL and additional rights");