1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
4 */
5
6#define pr_fmt(fmt)	"[drm-dp] %s: " fmt, __func__
7
8#include <drm/drm_print.h>
9
10#include "dp_reg.h"
11#include "dp_link.h"
12#include "dp_panel.h"
13
14#define DP_TEST_REQUEST_MASK		0x7F
15
16enum audio_sample_rate {
17	AUDIO_SAMPLE_RATE_32_KHZ	= 0x00,
18	AUDIO_SAMPLE_RATE_44_1_KHZ	= 0x01,
19	AUDIO_SAMPLE_RATE_48_KHZ	= 0x02,
20	AUDIO_SAMPLE_RATE_88_2_KHZ	= 0x03,
21	AUDIO_SAMPLE_RATE_96_KHZ	= 0x04,
22	AUDIO_SAMPLE_RATE_176_4_KHZ	= 0x05,
23	AUDIO_SAMPLE_RATE_192_KHZ	= 0x06,
24};
25
26enum audio_pattern_type {
27	AUDIO_TEST_PATTERN_OPERATOR_DEFINED	= 0x00,
28	AUDIO_TEST_PATTERN_SAWTOOTH		= 0x01,
29};
30
31struct dp_link_request {
32	u32 test_requested;
33	u32 test_link_rate;
34	u32 test_lane_count;
35};
36
37struct dp_link_private {
38	u32 prev_sink_count;
39	struct device *dev;
40	struct drm_dp_aux *aux;
41	struct dp_link dp_link;
42
43	struct dp_link_request request;
44	struct mutex psm_mutex;
45	u8 link_status[DP_LINK_STATUS_SIZE];
46};
47
48static int dp_aux_link_power_up(struct drm_dp_aux *aux,
49					struct dp_link_info *link)
50{
51	u8 value;
52	int err;
53
54	if (link->revision < 0x11)
55		return 0;
56
57	err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
58	if (err < 0)
59		return err;
60
61	value &= ~DP_SET_POWER_MASK;
62	value |= DP_SET_POWER_D0;
63
64	err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
65	if (err < 0)
66		return err;
67
68	usleep_range(1000, 2000);
69
70	return 0;
71}
72
73static int dp_aux_link_power_down(struct drm_dp_aux *aux,
74					struct dp_link_info *link)
75{
76	u8 value;
77	int err;
78
79	if (link->revision < 0x11)
80		return 0;
81
82	err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
83	if (err < 0)
84		return err;
85
86	value &= ~DP_SET_POWER_MASK;
87	value |= DP_SET_POWER_D3;
88
89	err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
90	if (err < 0)
91		return err;
92
93	return 0;
94}
95
96static int dp_link_get_period(struct dp_link_private *link, int const addr)
97{
98	int ret = 0;
99	u8 data;
100	u32 const max_audio_period = 0xA;
101
102	/* TEST_AUDIO_PERIOD_CH_XX */
103	if (drm_dp_dpcd_readb(link->aux, addr, &data) < 0) {
104		DRM_ERROR("failed to read test_audio_period (0x%x)\n", addr);
105		ret = -EINVAL;
106		goto exit;
107	}
108
109	/* Period - Bits 3:0 */
110	data = data & 0xF;
111	if ((int)data > max_audio_period) {
112		DRM_ERROR("invalid test_audio_period_ch_1 = 0x%x\n", data);
113		ret = -EINVAL;
114		goto exit;
115	}
116
117	ret = data;
118exit:
119	return ret;
120}
121
122static int dp_link_parse_audio_channel_period(struct dp_link_private *link)
123{
124	int ret = 0;
125	struct dp_link_test_audio *req = &link->dp_link.test_audio;
126
127	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH1);
128	if (ret == -EINVAL)
129		goto exit;
130
131	req->test_audio_period_ch_1 = ret;
132	DRM_DEBUG_DP("test_audio_period_ch_1 = 0x%x\n", ret);
133
134	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH2);
135	if (ret == -EINVAL)
136		goto exit;
137
138	req->test_audio_period_ch_2 = ret;
139	DRM_DEBUG_DP("test_audio_period_ch_2 = 0x%x\n", ret);
140
141	/* TEST_AUDIO_PERIOD_CH_3 (Byte 0x275) */
142	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH3);
143	if (ret == -EINVAL)
144		goto exit;
145
146	req->test_audio_period_ch_3 = ret;
147	DRM_DEBUG_DP("test_audio_period_ch_3 = 0x%x\n", ret);
148
149	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH4);
150	if (ret == -EINVAL)
151		goto exit;
152
153	req->test_audio_period_ch_4 = ret;
154	DRM_DEBUG_DP("test_audio_period_ch_4 = 0x%x\n", ret);
155
156	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH5);
157	if (ret == -EINVAL)
158		goto exit;
159
160	req->test_audio_period_ch_5 = ret;
161	DRM_DEBUG_DP("test_audio_period_ch_5 = 0x%x\n", ret);
162
163	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH6);
164	if (ret == -EINVAL)
165		goto exit;
166
167	req->test_audio_period_ch_6 = ret;
168	DRM_DEBUG_DP("test_audio_period_ch_6 = 0x%x\n", ret);
169
170	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH7);
171	if (ret == -EINVAL)
172		goto exit;
173
174	req->test_audio_period_ch_7 = ret;
175	DRM_DEBUG_DP("test_audio_period_ch_7 = 0x%x\n", ret);
176
177	ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH8);
178	if (ret == -EINVAL)
179		goto exit;
180
181	req->test_audio_period_ch_8 = ret;
182	DRM_DEBUG_DP("test_audio_period_ch_8 = 0x%x\n", ret);
183exit:
184	return ret;
185}
186
187static int dp_link_parse_audio_pattern_type(struct dp_link_private *link)
188{
189	int ret = 0;
190	u8 data;
191	ssize_t rlen;
192	int const max_audio_pattern_type = 0x1;
193
194	rlen = drm_dp_dpcd_readb(link->aux,
195				DP_TEST_AUDIO_PATTERN_TYPE, &data);
196	if (rlen < 0) {
197		DRM_ERROR("failed to read link audio mode. rlen=%zd\n", rlen);
198		return rlen;
199	}
200
201	/* Audio Pattern Type - Bits 7:0 */
202	if ((int)data > max_audio_pattern_type) {
203		DRM_ERROR("invalid audio pattern type = 0x%x\n", data);
204		ret = -EINVAL;
205		goto exit;
206	}
207
208	link->dp_link.test_audio.test_audio_pattern_type = data;
209	DRM_DEBUG_DP("audio pattern type = 0x%x\n", data);
210exit:
211	return ret;
212}
213
214static int dp_link_parse_audio_mode(struct dp_link_private *link)
215{
216	int ret = 0;
217	u8 data;
218	ssize_t rlen;
219	int const max_audio_sampling_rate = 0x6;
220	int const max_audio_channel_count = 0x8;
221	int sampling_rate = 0x0;
222	int channel_count = 0x0;
223
224	rlen = drm_dp_dpcd_readb(link->aux, DP_TEST_AUDIO_MODE, &data);
225	if (rlen < 0) {
226		DRM_ERROR("failed to read link audio mode. rlen=%zd\n", rlen);
227		return rlen;
228	}
229
230	/* Sampling Rate - Bits 3:0 */
231	sampling_rate = data & 0xF;
232	if (sampling_rate > max_audio_sampling_rate) {
233		DRM_ERROR("sampling rate (0x%x) greater than max (0x%x)\n",
234				sampling_rate, max_audio_sampling_rate);
235		ret = -EINVAL;
236		goto exit;
237	}
238
239	/* Channel Count - Bits 7:4 */
240	channel_count = ((data & 0xF0) >> 4) + 1;
241	if (channel_count > max_audio_channel_count) {
242		DRM_ERROR("channel_count (0x%x) greater than max (0x%x)\n",
243				channel_count, max_audio_channel_count);
244		ret = -EINVAL;
245		goto exit;
246	}
247
248	link->dp_link.test_audio.test_audio_sampling_rate = sampling_rate;
249	link->dp_link.test_audio.test_audio_channel_count = channel_count;
250	DRM_DEBUG_DP("sampling_rate = 0x%x, channel_count = 0x%x\n",
251					sampling_rate, channel_count);
252exit:
253	return ret;
254}
255
256static int dp_link_parse_audio_pattern_params(struct dp_link_private *link)
257{
258	int ret = 0;
259
260	ret = dp_link_parse_audio_mode(link);
261	if (ret)
262		goto exit;
263
264	ret = dp_link_parse_audio_pattern_type(link);
265	if (ret)
266		goto exit;
267
268	ret = dp_link_parse_audio_channel_period(link);
269
270exit:
271	return ret;
272}
273
274static bool dp_link_is_video_pattern_valid(u32 pattern)
275{
276	switch (pattern) {
277	case DP_NO_TEST_PATTERN:
278	case DP_COLOR_RAMP:
279	case DP_BLACK_AND_WHITE_VERTICAL_LINES:
280	case DP_COLOR_SQUARE:
281		return true;
282	default:
283		return false;
284	}
285}
286
287/**
288 * dp_link_is_bit_depth_valid() - validates the bit depth requested
289 * @tbd: bit depth requested by the sink
290 *
291 * Returns true if the requested bit depth is supported.
292 */
293static bool dp_link_is_bit_depth_valid(u32 tbd)
294{
295	/* DP_TEST_VIDEO_PATTERN_NONE is treated as invalid */
296	switch (tbd) {
297	case DP_TEST_BIT_DEPTH_6:
298	case DP_TEST_BIT_DEPTH_8:
299	case DP_TEST_BIT_DEPTH_10:
300		return true;
301	default:
302		return false;
303	}
304}
305
306static int dp_link_parse_timing_params1(struct dp_link_private *link,
307					int addr, int len, u32 *val)
308{
309	u8 bp[2];
310	int rlen;
311
312	if (len != 2)
313		return -EINVAL;
314
315	/* Read the requested video link pattern (Byte 0x221). */
316	rlen = drm_dp_dpcd_read(link->aux, addr, bp, len);
317	if (rlen < len) {
318		DRM_ERROR("failed to read 0x%x\n", addr);
319		return -EINVAL;
320	}
321
322	*val = bp[1] | (bp[0] << 8);
323
324	return 0;
325}
326
327static int dp_link_parse_timing_params2(struct dp_link_private *link,
328					int addr, int len,
329					u32 *val1, u32 *val2)
330{
331	u8 bp[2];
332	int rlen;
333
334	if (len != 2)
335		return -EINVAL;
336
337	/* Read the requested video link pattern (Byte 0x221). */
338	rlen = drm_dp_dpcd_read(link->aux, addr, bp, len);
339	if (rlen < len) {
340		DRM_ERROR("failed to read 0x%x\n", addr);
341		return -EINVAL;
342	}
343
344	*val1 = (bp[0] & BIT(7)) >> 7;
345	*val2 = bp[1] | ((bp[0] & 0x7F) << 8);
346
347	return 0;
348}
349
350static int dp_link_parse_timing_params3(struct dp_link_private *link,
351					int addr, u32 *val)
352{
353	u8 bp;
354	u32 len = 1;
355	int rlen;
356
357	rlen = drm_dp_dpcd_read(link->aux, addr, &bp, len);
358	if (rlen < 1) {
359		DRM_ERROR("failed to read 0x%x\n", addr);
360		return -EINVAL;
361	}
362	*val = bp;
363
364	return 0;
365}
366
367/**
368 * dp_parse_video_pattern_params() - parses video pattern parameters from DPCD
369 * @link: Display Port Driver data
370 *
371 * Returns 0 if it successfully parses the video link pattern and the link
372 * bit depth requested by the sink and, and if the values parsed are valid.
373 */
374static int dp_link_parse_video_pattern_params(struct dp_link_private *link)
375{
376	int ret = 0;
377	ssize_t rlen;
378	u8 bp;
379
380	rlen = drm_dp_dpcd_readb(link->aux, DP_TEST_PATTERN, &bp);
381	if (rlen < 0) {
382		DRM_ERROR("failed to read link video pattern. rlen=%zd\n",
383			rlen);
384		return rlen;
385	}
386
387	if (!dp_link_is_video_pattern_valid(bp)) {
388		DRM_ERROR("invalid link video pattern = 0x%x\n", bp);
389		ret = -EINVAL;
390		return ret;
391	}
392
393	link->dp_link.test_video.test_video_pattern = bp;
394
395	/* Read the requested color bit depth and dynamic range (Byte 0x232) */
396	rlen = drm_dp_dpcd_readb(link->aux, DP_TEST_MISC0, &bp);
397	if (rlen < 0) {
398		DRM_ERROR("failed to read link bit depth. rlen=%zd\n", rlen);
399		return rlen;
400	}
401
402	/* Dynamic Range */
403	link->dp_link.test_video.test_dyn_range =
404			(bp & DP_TEST_DYNAMIC_RANGE_CEA);
405
406	/* Color bit depth */
407	bp &= DP_TEST_BIT_DEPTH_MASK;
408	if (!dp_link_is_bit_depth_valid(bp)) {
409		DRM_ERROR("invalid link bit depth = 0x%x\n", bp);
410		ret = -EINVAL;
411		return ret;
412	}
413
414	link->dp_link.test_video.test_bit_depth = bp;
415
416	/* resolution timing params */
417	ret = dp_link_parse_timing_params1(link, DP_TEST_H_TOTAL_HI, 2,
418			&link->dp_link.test_video.test_h_total);
419	if (ret) {
420		DRM_ERROR("failed to parse test_htotal(DP_TEST_H_TOTAL_HI)\n");
421		return ret;
422	}
423
424	ret = dp_link_parse_timing_params1(link, DP_TEST_V_TOTAL_HI, 2,
425			&link->dp_link.test_video.test_v_total);
426	if (ret) {
427		DRM_ERROR("failed to parse test_v_total(DP_TEST_V_TOTAL_HI)\n");
428		return ret;
429	}
430
431	ret = dp_link_parse_timing_params1(link, DP_TEST_H_START_HI, 2,
432			&link->dp_link.test_video.test_h_start);
433	if (ret) {
434		DRM_ERROR("failed to parse test_h_start(DP_TEST_H_START_HI)\n");
435		return ret;
436	}
437
438	ret = dp_link_parse_timing_params1(link, DP_TEST_V_START_HI, 2,
439			&link->dp_link.test_video.test_v_start);
440	if (ret) {
441		DRM_ERROR("failed to parse test_v_start(DP_TEST_V_START_HI)\n");
442		return ret;
443	}
444
445	ret = dp_link_parse_timing_params2(link, DP_TEST_HSYNC_HI, 2,
446			&link->dp_link.test_video.test_hsync_pol,
447			&link->dp_link.test_video.test_hsync_width);
448	if (ret) {
449		DRM_ERROR("failed to parse (DP_TEST_HSYNC_HI)\n");
450		return ret;
451	}
452
453	ret = dp_link_parse_timing_params2(link, DP_TEST_VSYNC_HI, 2,
454			&link->dp_link.test_video.test_vsync_pol,
455			&link->dp_link.test_video.test_vsync_width);
456	if (ret) {
457		DRM_ERROR("failed to parse (DP_TEST_VSYNC_HI)\n");
458		return ret;
459	}
460
461	ret = dp_link_parse_timing_params1(link, DP_TEST_H_WIDTH_HI, 2,
462			&link->dp_link.test_video.test_h_width);
463	if (ret) {
464		DRM_ERROR("failed to parse test_h_width(DP_TEST_H_WIDTH_HI)\n");
465		return ret;
466	}
467
468	ret = dp_link_parse_timing_params1(link, DP_TEST_V_HEIGHT_HI, 2,
469			&link->dp_link.test_video.test_v_height);
470	if (ret) {
471		DRM_ERROR("failed to parse test_v_height\n");
472		return ret;
473	}
474
475	ret = dp_link_parse_timing_params3(link, DP_TEST_MISC1,
476		&link->dp_link.test_video.test_rr_d);
477	link->dp_link.test_video.test_rr_d &= DP_TEST_REFRESH_DENOMINATOR;
478	if (ret) {
479		DRM_ERROR("failed to parse test_rr_d (DP_TEST_MISC1)\n");
480		return ret;
481	}
482
483	ret = dp_link_parse_timing_params3(link, DP_TEST_REFRESH_RATE_NUMERATOR,
484		&link->dp_link.test_video.test_rr_n);
485	if (ret) {
486		DRM_ERROR("failed to parse test_rr_n\n");
487		return ret;
488	}
489
490	DRM_DEBUG_DP("link video pattern = 0x%x\n"
491		"link dynamic range = 0x%x\n"
492		"link bit depth = 0x%x\n"
493		"TEST_H_TOTAL = %d, TEST_V_TOTAL = %d\n"
494		"TEST_H_START = %d, TEST_V_START = %d\n"
495		"TEST_HSYNC_POL = %d\n"
496		"TEST_HSYNC_WIDTH = %d\n"
497		"TEST_VSYNC_POL = %d\n"
498		"TEST_VSYNC_WIDTH = %d\n"
499		"TEST_H_WIDTH = %d\n"
500		"TEST_V_HEIGHT = %d\n"
501		"TEST_REFRESH_DENOMINATOR = %d\n"
502		 "TEST_REFRESH_NUMERATOR = %d\n",
503		link->dp_link.test_video.test_video_pattern,
504		link->dp_link.test_video.test_dyn_range,
505		link->dp_link.test_video.test_bit_depth,
506		link->dp_link.test_video.test_h_total,
507		link->dp_link.test_video.test_v_total,
508		link->dp_link.test_video.test_h_start,
509		link->dp_link.test_video.test_v_start,
510		link->dp_link.test_video.test_hsync_pol,
511		link->dp_link.test_video.test_hsync_width,
512		link->dp_link.test_video.test_vsync_pol,
513		link->dp_link.test_video.test_vsync_width,
514		link->dp_link.test_video.test_h_width,
515		link->dp_link.test_video.test_v_height,
516		link->dp_link.test_video.test_rr_d,
517		link->dp_link.test_video.test_rr_n);
518
519	return ret;
520}
521
522/**
523 * dp_link_parse_link_training_params() - parses link training parameters from
524 * DPCD
525 * @link: Display Port Driver data
526 *
527 * Returns 0 if it successfully parses the link rate (Byte 0x219) and lane
528 * count (Byte 0x220), and if these values parse are valid.
529 */
530static int dp_link_parse_link_training_params(struct dp_link_private *link)
531{
532	u8 bp;
533	ssize_t rlen;
534
535	rlen = drm_dp_dpcd_readb(link->aux, DP_TEST_LINK_RATE,	&bp);
536	if (rlen < 0) {
537		DRM_ERROR("failed to read link rate. rlen=%zd\n", rlen);
538		return rlen;
539	}
540
541	if (!is_link_rate_valid(bp)) {
542		DRM_ERROR("invalid link rate = 0x%x\n", bp);
543		return -EINVAL;
544	}
545
546	link->request.test_link_rate = bp;
547	DRM_DEBUG_DP("link rate = 0x%x\n", link->request.test_link_rate);
548
549	rlen = drm_dp_dpcd_readb(link->aux, DP_TEST_LANE_COUNT, &bp);
550	if (rlen < 0) {
551		DRM_ERROR("failed to read lane count. rlen=%zd\n", rlen);
552		return rlen;
553	}
554	bp &= DP_MAX_LANE_COUNT_MASK;
555
556	if (!is_lane_count_valid(bp)) {
557		DRM_ERROR("invalid lane count = 0x%x\n", bp);
558		return -EINVAL;
559	}
560
561	link->request.test_lane_count = bp;
562	DRM_DEBUG_DP("lane count = 0x%x\n", link->request.test_lane_count);
563	return 0;
564}
565
566/**
567 * dp_parse_phy_test_params() - parses the phy link parameters
568 * @link: Display Port Driver data
569 *
570 * Parses the DPCD (Byte 0x248) for the DP PHY link pattern that is being
571 * requested.
572 */
573static int dp_link_parse_phy_test_params(struct dp_link_private *link)
574{
575	u8 data;
576	ssize_t rlen;
577
578	rlen = drm_dp_dpcd_readb(link->aux, DP_PHY_TEST_PATTERN,
579					&data);
580	if (rlen < 0) {
581		DRM_ERROR("failed to read phy link pattern. rlen=%zd\n", rlen);
582		return rlen;
583	}
584
585	link->dp_link.phy_params.phy_test_pattern_sel = data & 0x07;
586
587	DRM_DEBUG_DP("phy_test_pattern_sel = 0x%x\n", data);
588
589	switch (data) {
590	case DP_PHY_TEST_PATTERN_SEL_MASK:
591	case DP_PHY_TEST_PATTERN_NONE:
592	case DP_PHY_TEST_PATTERN_D10_2:
593	case DP_PHY_TEST_PATTERN_ERROR_COUNT:
594	case DP_PHY_TEST_PATTERN_PRBS7:
595	case DP_PHY_TEST_PATTERN_80BIT_CUSTOM:
596	case DP_PHY_TEST_PATTERN_CP2520:
597		return 0;
598	default:
599		return -EINVAL;
600	}
601}
602
603/**
604 * dp_link_is_video_audio_test_requested() - checks for audio/video link request
605 * @link: link requested by the sink
606 *
607 * Returns true if the requested link is a permitted audio/video link.
608 */
609static bool dp_link_is_video_audio_test_requested(u32 link)
610{
611	u8 video_audio_test = (DP_TEST_LINK_VIDEO_PATTERN |
612				DP_TEST_LINK_AUDIO_PATTERN |
613				DP_TEST_LINK_AUDIO_DISABLED_VIDEO);
614
615	return ((link & video_audio_test) &&
616		!(link & ~video_audio_test));
617}
618
619/**
620 * dp_link_parse_request() - parses link request parameters from sink
621 * @link: Display Port Driver data
622 *
623 * Parses the DPCD to check if an automated link is requested (Byte 0x201),
624 * and what type of link automation is being requested (Byte 0x218).
625 */
626static int dp_link_parse_request(struct dp_link_private *link)
627{
628	int ret = 0;
629	u8 data;
630	ssize_t rlen;
631
632	/**
633	 * Read the device service IRQ vector (Byte 0x201) to determine
634	 * whether an automated link has been requested by the sink.
635	 */
636	rlen = drm_dp_dpcd_readb(link->aux,
637				DP_DEVICE_SERVICE_IRQ_VECTOR, &data);
638	if (rlen < 0) {
639		DRM_ERROR("aux read failed. rlen=%zd\n", rlen);
640		return rlen;
641	}
642
643	DRM_DEBUG_DP("device service irq vector = 0x%x\n", data);
644
645	if (!(data & DP_AUTOMATED_TEST_REQUEST)) {
646		DRM_DEBUG_DP("no test requested\n");
647		return 0;
648	}
649
650	/**
651	 * Read the link request byte (Byte 0x218) to determine what type
652	 * of automated link has been requested by the sink.
653	 */
654	rlen = drm_dp_dpcd_readb(link->aux, DP_TEST_REQUEST, &data);
655	if (rlen < 0) {
656		DRM_ERROR("aux read failed. rlen=%zd\n", rlen);
657		return rlen;
658	}
659
660	if (!data || (data == DP_TEST_LINK_FAUX_PATTERN)) {
661		DRM_DEBUG_DP("link 0x%x not supported\n", data);
662		goto end;
663	}
664
665	DRM_DEBUG_DP("Test:(0x%x) requested\n", data);
666	link->request.test_requested = data;
667	if (link->request.test_requested == DP_TEST_LINK_PHY_TEST_PATTERN) {
668		ret = dp_link_parse_phy_test_params(link);
669		if (ret)
670			goto end;
671		ret = dp_link_parse_link_training_params(link);
672		if (ret)
673			goto end;
674	}
675
676	if (link->request.test_requested == DP_TEST_LINK_TRAINING) {
677		ret = dp_link_parse_link_training_params(link);
678		if (ret)
679			goto end;
680	}
681
682	if (dp_link_is_video_audio_test_requested(
683			link->request.test_requested)) {
684		ret = dp_link_parse_video_pattern_params(link);
685		if (ret)
686			goto end;
687
688		ret = dp_link_parse_audio_pattern_params(link);
689	}
690end:
691	/*
692	 * Send a DP_TEST_ACK if all link parameters are valid, otherwise send
693	 * a DP_TEST_NAK.
694	 */
695	if (ret) {
696		link->dp_link.test_response = DP_TEST_NAK;
697	} else {
698		if (link->request.test_requested != DP_TEST_LINK_EDID_READ)
699			link->dp_link.test_response = DP_TEST_ACK;
700		else
701			link->dp_link.test_response =
702				DP_TEST_EDID_CHECKSUM_WRITE;
703	}
704
705	return ret;
706}
707
708/**
709 * dp_link_parse_sink_count() - parses the sink count
710 * @dp_link: pointer to link module data
711 *
712 * Parses the DPCD to check if there is an update to the sink count
713 * (Byte 0x200), and whether all the sink devices connected have Content
714 * Protection enabled.
715 */
716static int dp_link_parse_sink_count(struct dp_link *dp_link)
717{
718	ssize_t rlen;
719	bool cp_ready;
720
721	struct dp_link_private *link = container_of(dp_link,
722			struct dp_link_private, dp_link);
723
724	rlen = drm_dp_dpcd_readb(link->aux, DP_SINK_COUNT,
725				 &link->dp_link.sink_count);
726	if (rlen < 0) {
727		DRM_ERROR("sink count read failed. rlen=%zd\n", rlen);
728		return rlen;
729	}
730
731	cp_ready = link->dp_link.sink_count & DP_SINK_CP_READY;
732
733	link->dp_link.sink_count =
734		DP_GET_SINK_COUNT(link->dp_link.sink_count);
735
736	DRM_DEBUG_DP("sink_count = 0x%x, cp_ready = 0x%x\n",
737		link->dp_link.sink_count, cp_ready);
738	return 0;
739}
740
741static void dp_link_parse_sink_status_field(struct dp_link_private *link)
742{
743	int len = 0;
744
745	link->prev_sink_count = link->dp_link.sink_count;
746	dp_link_parse_sink_count(&link->dp_link);
747
748	len = drm_dp_dpcd_read_link_status(link->aux,
749		link->link_status);
750	if (len < DP_LINK_STATUS_SIZE)
751		DRM_ERROR("DP link status read failed\n");
752	dp_link_parse_request(link);
753}
754
755/**
756 * dp_link_process_link_training_request() - processes new training requests
757 * @link: Display Port link data
758 *
759 * This function will handle new link training requests that are initiated by
760 * the sink. In particular, it will update the requested lane count and link
761 * rate, and then trigger the link retraining procedure.
762 *
763 * The function will return 0 if a link training request has been processed,
764 * otherwise it will return -EINVAL.
765 */
766static int dp_link_process_link_training_request(struct dp_link_private *link)
767{
768	if (link->request.test_requested != DP_TEST_LINK_TRAINING)
769		return -EINVAL;
770
771	DRM_DEBUG_DP("Test:0x%x link rate = 0x%x, lane count = 0x%x\n",
772			DP_TEST_LINK_TRAINING,
773			link->request.test_link_rate,
774			link->request.test_lane_count);
775
776	link->dp_link.link_params.num_lanes = link->request.test_lane_count;
777	link->dp_link.link_params.rate =
778		drm_dp_bw_code_to_link_rate(link->request.test_link_rate);
779
780	return 0;
781}
782
783bool dp_link_send_test_response(struct dp_link *dp_link)
784{
785	struct dp_link_private *link = NULL;
786	int ret = 0;
787
788	if (!dp_link) {
789		DRM_ERROR("invalid input\n");
790		return false;
791	}
792
793	link = container_of(dp_link, struct dp_link_private, dp_link);
794
795	ret = drm_dp_dpcd_writeb(link->aux, DP_TEST_RESPONSE,
796			dp_link->test_response);
797
798	return ret == 1;
799}
800
801int dp_link_psm_config(struct dp_link *dp_link,
802			      struct dp_link_info *link_info, bool enable)
803{
804	struct dp_link_private *link = NULL;
805	int ret = 0;
806
807	if (!dp_link) {
808		DRM_ERROR("invalid params\n");
809		return -EINVAL;
810	}
811
812	link = container_of(dp_link, struct dp_link_private, dp_link);
813
814	mutex_lock(&link->psm_mutex);
815	if (enable)
816		ret = dp_aux_link_power_down(link->aux, link_info);
817	else
818		ret = dp_aux_link_power_up(link->aux, link_info);
819
820	if (ret)
821		DRM_ERROR("Failed to %s low power mode\n", enable ?
822							"enter" : "exit");
823	else
824		dp_link->psm_enabled = enable;
825
826	mutex_unlock(&link->psm_mutex);
827	return ret;
828}
829
830bool dp_link_send_edid_checksum(struct dp_link *dp_link, u8 checksum)
831{
832	struct dp_link_private *link = NULL;
833	int ret = 0;
834
835	if (!dp_link) {
836		DRM_ERROR("invalid input\n");
837		return false;
838	}
839
840	link = container_of(dp_link, struct dp_link_private, dp_link);
841
842	ret = drm_dp_dpcd_writeb(link->aux, DP_TEST_EDID_CHECKSUM,
843						checksum);
844	return ret == 1;
845}
846
847static int dp_link_parse_vx_px(struct dp_link_private *link)
848{
849	int ret = 0;
850
851	DRM_DEBUG_DP("vx: 0=%d, 1=%d, 2=%d, 3=%d\n",
852		drm_dp_get_adjust_request_voltage(link->link_status, 0),
853		drm_dp_get_adjust_request_voltage(link->link_status, 1),
854		drm_dp_get_adjust_request_voltage(link->link_status, 2),
855		drm_dp_get_adjust_request_voltage(link->link_status, 3));
856
857	DRM_DEBUG_DP("px: 0=%d, 1=%d, 2=%d, 3=%d\n",
858		drm_dp_get_adjust_request_pre_emphasis(link->link_status, 0),
859		drm_dp_get_adjust_request_pre_emphasis(link->link_status, 1),
860		drm_dp_get_adjust_request_pre_emphasis(link->link_status, 2),
861		drm_dp_get_adjust_request_pre_emphasis(link->link_status, 3));
862
863	/**
864	 * Update the voltage and pre-emphasis levels as per DPCD request
865	 * vector.
866	 */
867	DRM_DEBUG_DP("Current: v_level = 0x%x, p_level = 0x%x\n",
868			link->dp_link.phy_params.v_level,
869			link->dp_link.phy_params.p_level);
870	link->dp_link.phy_params.v_level =
871		drm_dp_get_adjust_request_voltage(link->link_status, 0);
872	link->dp_link.phy_params.p_level =
873		drm_dp_get_adjust_request_pre_emphasis(link->link_status, 0);
874
875	link->dp_link.phy_params.p_level >>= DP_TRAIN_PRE_EMPHASIS_SHIFT;
876
877	DRM_DEBUG_DP("Requested: v_level = 0x%x, p_level = 0x%x\n",
878			link->dp_link.phy_params.v_level,
879			link->dp_link.phy_params.p_level);
880
881	return ret;
882}
883
884/**
885 * dp_link_process_phy_test_pattern_request() - process new phy link requests
886 * @link: Display Port Driver data
887 *
888 * This function will handle new phy link pattern requests that are initiated
889 * by the sink. The function will return 0 if a phy link pattern has been
890 * processed, otherwise it will return -EINVAL.
891 */
892static int dp_link_process_phy_test_pattern_request(
893		struct dp_link_private *link)
894{
895	int ret = 0;
896
897	if (!(link->request.test_requested & DP_TEST_LINK_PHY_TEST_PATTERN)) {
898		DRM_DEBUG_DP("no phy test\n");
899		return -EINVAL;
900	}
901
902	if (!is_link_rate_valid(link->request.test_link_rate) ||
903		!is_lane_count_valid(link->request.test_lane_count)) {
904		DRM_ERROR("Invalid: link rate = 0x%x,lane count = 0x%x\n",
905				link->request.test_link_rate,
906				link->request.test_lane_count);
907		return -EINVAL;
908	}
909
910	DRM_DEBUG_DP("Current: rate = 0x%x, lane count = 0x%x\n",
911			link->dp_link.link_params.rate,
912			link->dp_link.link_params.num_lanes);
913
914	DRM_DEBUG_DP("Requested: rate = 0x%x, lane count = 0x%x\n",
915			link->request.test_link_rate,
916			link->request.test_lane_count);
917
918	link->dp_link.link_params.num_lanes = link->request.test_lane_count;
919	link->dp_link.link_params.rate =
920		drm_dp_bw_code_to_link_rate(link->request.test_link_rate);
921
922	ret = dp_link_parse_vx_px(link);
923
924	if (ret)
925		DRM_ERROR("parse_vx_px failed. ret=%d\n", ret);
926
927	return ret;
928}
929
930static u8 get_link_status(const u8 link_status[DP_LINK_STATUS_SIZE], int r)
931{
932	return link_status[r - DP_LANE0_1_STATUS];
933}
934
935/**
936 * dp_link_process_link_status_update() - processes link status updates
937 * @link: Display Port link module data
938 *
939 * This function will check for changes in the link status, e.g. clock
940 * recovery done on all lanes, and trigger link training if there is a
941 * failure/error on the link.
942 *
943 * The function will return 0 if the a link status update has been processed,
944 * otherwise it will return -EINVAL.
945 */
946static int dp_link_process_link_status_update(struct dp_link_private *link)
947{
948       bool channel_eq_done = drm_dp_channel_eq_ok(link->link_status,
949                       link->dp_link.link_params.num_lanes);
950
951       bool clock_recovery_done = drm_dp_clock_recovery_ok(link->link_status,
952                       link->dp_link.link_params.num_lanes);
953
954       DRM_DEBUG_DP("channel_eq_done = %d, clock_recovery_done = %d\n",
955                        channel_eq_done, clock_recovery_done);
956
957       if (channel_eq_done && clock_recovery_done)
958               return -EINVAL;
959
960
961       return 0;
962}
963
964/**
965 * dp_link_process_downstream_port_status_change() - process port status changes
966 * @link: Display Port Driver data
967 *
968 * This function will handle downstream port updates that are initiated by
969 * the sink. If the downstream port status has changed, the EDID is read via
970 * AUX.
971 *
972 * The function will return 0 if a downstream port update has been
973 * processed, otherwise it will return -EINVAL.
974 */
975static int dp_link_process_ds_port_status_change(struct dp_link_private *link)
976{
977	if (get_link_status(link->link_status, DP_LANE_ALIGN_STATUS_UPDATED) &
978					DP_DOWNSTREAM_PORT_STATUS_CHANGED)
979		goto reset;
980
981	if (link->prev_sink_count == link->dp_link.sink_count)
982		return -EINVAL;
983
984reset:
985	/* reset prev_sink_count */
986	link->prev_sink_count = link->dp_link.sink_count;
987
988	return 0;
989}
990
991static bool dp_link_is_video_pattern_requested(struct dp_link_private *link)
992{
993	return (link->request.test_requested & DP_TEST_LINK_VIDEO_PATTERN)
994		&& !(link->request.test_requested &
995		DP_TEST_LINK_AUDIO_DISABLED_VIDEO);
996}
997
998static bool dp_link_is_audio_pattern_requested(struct dp_link_private *link)
999{
1000	return (link->request.test_requested & DP_TEST_LINK_AUDIO_PATTERN);
1001}
1002
1003static void dp_link_reset_data(struct dp_link_private *link)
1004{
1005	link->request = (const struct dp_link_request){ 0 };
1006	link->dp_link.test_video = (const struct dp_link_test_video){ 0 };
1007	link->dp_link.test_video.test_bit_depth = DP_TEST_BIT_DEPTH_UNKNOWN;
1008	link->dp_link.test_audio = (const struct dp_link_test_audio){ 0 };
1009	link->dp_link.phy_params.phy_test_pattern_sel = 0;
1010	link->dp_link.sink_request = 0;
1011	link->dp_link.test_response = 0;
1012}
1013
1014/**
1015 * dp_link_process_request() - handle HPD IRQ transition to HIGH
1016 * @dp_link: pointer to link module data
1017 *
1018 * This function will handle the HPD IRQ state transitions from LOW to HIGH
1019 * (including cases when there are back to back HPD IRQ HIGH) indicating
1020 * the start of a new link training request or sink status update.
1021 */
1022int dp_link_process_request(struct dp_link *dp_link)
1023{
1024	int ret = 0;
1025	struct dp_link_private *link;
1026
1027	if (!dp_link) {
1028		DRM_ERROR("invalid input\n");
1029		return -EINVAL;
1030	}
1031
1032	link = container_of(dp_link, struct dp_link_private, dp_link);
1033
1034	dp_link_reset_data(link);
1035
1036	dp_link_parse_sink_status_field(link);
1037
1038	if (link->request.test_requested == DP_TEST_LINK_EDID_READ) {
1039		dp_link->sink_request |= DP_TEST_LINK_EDID_READ;
1040		return ret;
1041	}
1042
1043	ret = dp_link_process_ds_port_status_change(link);
1044	if (!ret) {
1045		dp_link->sink_request |= DS_PORT_STATUS_CHANGED;
1046		return ret;
1047	}
1048
1049	ret = dp_link_process_link_training_request(link);
1050	if (!ret) {
1051		dp_link->sink_request |= DP_TEST_LINK_TRAINING;
1052		return ret;
1053	}
1054
1055	ret = dp_link_process_phy_test_pattern_request(link);
1056	if (!ret) {
1057		dp_link->sink_request |= DP_TEST_LINK_PHY_TEST_PATTERN;
1058		return ret;
1059	}
1060
1061	ret = dp_link_process_link_status_update(link);
1062	if (!ret) {
1063		dp_link->sink_request |= DP_LINK_STATUS_UPDATED;
1064		return ret;
1065	}
1066
1067	if (dp_link_is_video_pattern_requested(link)) {
1068		ret = 0;
1069		dp_link->sink_request |= DP_TEST_LINK_VIDEO_PATTERN;
1070	}
1071
1072	if (dp_link_is_audio_pattern_requested(link)) {
1073		dp_link->sink_request |= DP_TEST_LINK_AUDIO_PATTERN;
1074		return -EINVAL;
1075	}
1076
1077	return ret;
1078}
1079
1080int dp_link_get_colorimetry_config(struct dp_link *dp_link)
1081{
1082	u32 cc = DP_MISC0_COLORIMERY_CFG_LEGACY_RGB;
1083	struct dp_link_private *link;
1084
1085	if (!dp_link) {
1086		DRM_ERROR("invalid input\n");
1087		return -EINVAL;
1088	}
1089
1090	link = container_of(dp_link, struct dp_link_private, dp_link);
1091
1092	/*
1093	 * Unless a video pattern CTS test is ongoing, use RGB_VESA
1094	 * Only RGB_VESA and RGB_CEA supported for now
1095	 */
1096	if (dp_link_is_video_pattern_requested(link)) {
1097		if (link->dp_link.test_video.test_dyn_range &
1098					DP_TEST_DYNAMIC_RANGE_CEA)
1099			cc = DP_MISC0_COLORIMERY_CFG_CEA_RGB;
1100	}
1101
1102	return cc;
1103}
1104
1105int dp_link_adjust_levels(struct dp_link *dp_link, u8 *link_status)
1106{
1107	int i;
1108	int v_max = 0, p_max = 0;
1109
1110	if (!dp_link) {
1111		DRM_ERROR("invalid input\n");
1112		return -EINVAL;
1113	}
1114
1115	/* use the max level across lanes */
1116	for (i = 0; i < dp_link->link_params.num_lanes; i++) {
1117		u8 data_v = drm_dp_get_adjust_request_voltage(link_status, i);
1118		u8 data_p = drm_dp_get_adjust_request_pre_emphasis(link_status,
1119									 i);
1120		DRM_DEBUG_DP("lane=%d req_vol_swing=%d req_pre_emphasis=%d\n",
1121				i, data_v, data_p);
1122		if (v_max < data_v)
1123			v_max = data_v;
1124		if (p_max < data_p)
1125			p_max = data_p;
1126	}
1127
1128	dp_link->phy_params.v_level = v_max >> DP_TRAIN_VOLTAGE_SWING_SHIFT;
1129	dp_link->phy_params.p_level = p_max >> DP_TRAIN_PRE_EMPHASIS_SHIFT;
1130
1131	/**
1132	 * Adjust the voltage swing and pre-emphasis level combination to within
1133	 * the allowable range.
1134	 */
1135	if (dp_link->phy_params.v_level > DP_TRAIN_VOLTAGE_SWING_MAX) {
1136		DRM_DEBUG_DP("Requested vSwingLevel=%d, change to %d\n",
1137			dp_link->phy_params.v_level,
1138			DP_TRAIN_VOLTAGE_SWING_MAX);
1139		dp_link->phy_params.v_level = DP_TRAIN_VOLTAGE_SWING_MAX;
1140	}
1141
1142	if (dp_link->phy_params.p_level > DP_TRAIN_PRE_EMPHASIS_MAX) {
1143		DRM_DEBUG_DP("Requested preEmphasisLevel=%d, change to %d\n",
1144			dp_link->phy_params.p_level,
1145			DP_TRAIN_PRE_EMPHASIS_MAX);
1146		dp_link->phy_params.p_level = DP_TRAIN_PRE_EMPHASIS_MAX;
1147	}
1148
1149	if ((dp_link->phy_params.p_level > DP_TRAIN_PRE_EMPHASIS_LVL_1)
1150		&& (dp_link->phy_params.v_level ==
1151			DP_TRAIN_VOLTAGE_SWING_LVL_2)) {
1152		DRM_DEBUG_DP("Requested preEmphasisLevel=%d, change to %d\n",
1153			dp_link->phy_params.p_level,
1154			DP_TRAIN_PRE_EMPHASIS_LVL_1);
1155		dp_link->phy_params.p_level = DP_TRAIN_PRE_EMPHASIS_LVL_1;
1156	}
1157
1158	DRM_DEBUG_DP("adjusted: v_level=%d, p_level=%d\n",
1159		dp_link->phy_params.v_level, dp_link->phy_params.p_level);
1160
1161	return 0;
1162}
1163
1164void dp_link_reset_phy_params_vx_px(struct dp_link *dp_link)
1165{
1166	dp_link->phy_params.v_level = 0;
1167	dp_link->phy_params.p_level = 0;
1168}
1169
1170u32 dp_link_get_test_bits_depth(struct dp_link *dp_link, u32 bpp)
1171{
1172	u32 tbd;
1173
1174	/*
1175	 * Few simplistic rules and assumptions made here:
1176	 *    1. Test bit depth is bit depth per color component
1177	 *    2. Assume 3 color components
1178	 */
1179	switch (bpp) {
1180	case 18:
1181		tbd = DP_TEST_BIT_DEPTH_6;
1182		break;
1183	case 24:
1184		tbd = DP_TEST_BIT_DEPTH_8;
1185		break;
1186	case 30:
1187		tbd = DP_TEST_BIT_DEPTH_10;
1188		break;
1189	default:
1190		tbd = DP_TEST_BIT_DEPTH_UNKNOWN;
1191		break;
1192	}
1193
1194	if (tbd != DP_TEST_BIT_DEPTH_UNKNOWN)
1195		tbd = (tbd >> DP_TEST_BIT_DEPTH_SHIFT);
1196
1197	return tbd;
1198}
1199
1200struct dp_link *dp_link_get(struct device *dev, struct drm_dp_aux *aux)
1201{
1202	struct dp_link_private *link;
1203	struct dp_link *dp_link;
1204
1205	if (!dev || !aux) {
1206		DRM_ERROR("invalid input\n");
1207		return ERR_PTR(-EINVAL);
1208	}
1209
1210	link = devm_kzalloc(dev, sizeof(*link), GFP_KERNEL);
1211	if (!link)
1212		return ERR_PTR(-ENOMEM);
1213
1214	link->dev   = dev;
1215	link->aux   = aux;
1216
1217	mutex_init(&link->psm_mutex);
1218	dp_link = &link->dp_link;
1219
1220	return dp_link;
1221}
1222