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_device *drm_dev;
41 struct drm_dp_aux *aux;
42 struct dp_link dp_link;
43
44 struct dp_link_request request;
45 struct mutex psm_mutex;
46 u8 link_status[DP_LINK_STATUS_SIZE];
47};
48
49static int dp_aux_link_power_up(struct drm_dp_aux *aux,
50 struct dp_link_info *link)
51{
52 u8 value;
53 ssize_t len;
54 int i;
55
56 if (link->revision < 0x11)
57 return 0;
58
59 len = drm_dp_dpcd_readb(aux, DP_SET_POWER, valuep: &value);
60 if (len < 0)
61 return len;
62
63 value &= ~DP_SET_POWER_MASK;
64 value |= DP_SET_POWER_D0;
65
66 /* retry for 1ms to give the sink time to wake up */
67 for (i = 0; i < 3; i++) {
68 len = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
69 usleep_range(min: 1000, max: 2000);
70 if (len == 1)
71 break;
72 }
73
74 return 0;
75}
76
77static int dp_aux_link_power_down(struct drm_dp_aux *aux,
78 struct dp_link_info *link)
79{
80 u8 value;
81 int err;
82
83 if (link->revision < 0x11)
84 return 0;
85
86 err = drm_dp_dpcd_readb(aux, DP_SET_POWER, valuep: &value);
87 if (err < 0)
88 return err;
89
90 value &= ~DP_SET_POWER_MASK;
91 value |= DP_SET_POWER_D3;
92
93 err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
94 if (err < 0)
95 return err;
96
97 return 0;
98}
99
100static int dp_link_get_period(struct dp_link_private *link, int const addr)
101{
102 int ret = 0;
103 u8 data;
104 u32 const max_audio_period = 0xA;
105
106 /* TEST_AUDIO_PERIOD_CH_XX */
107 if (drm_dp_dpcd_readb(aux: link->aux, offset: addr, valuep: &data) < 0) {
108 DRM_ERROR("failed to read test_audio_period (0x%x)\n", addr);
109 ret = -EINVAL;
110 goto exit;
111 }
112
113 /* Period - Bits 3:0 */
114 data = data & 0xF;
115 if ((int)data > max_audio_period) {
116 DRM_ERROR("invalid test_audio_period_ch_1 = 0x%x\n", data);
117 ret = -EINVAL;
118 goto exit;
119 }
120
121 ret = data;
122exit:
123 return ret;
124}
125
126static int dp_link_parse_audio_channel_period(struct dp_link_private *link)
127{
128 int ret = 0;
129 struct dp_link_test_audio *req = &link->dp_link.test_audio;
130
131 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH1);
132 if (ret == -EINVAL)
133 goto exit;
134
135 req->test_audio_period_ch_1 = ret;
136 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_1 = 0x%x\n", ret);
137
138 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH2);
139 if (ret == -EINVAL)
140 goto exit;
141
142 req->test_audio_period_ch_2 = ret;
143 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_2 = 0x%x\n", ret);
144
145 /* TEST_AUDIO_PERIOD_CH_3 (Byte 0x275) */
146 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH3);
147 if (ret == -EINVAL)
148 goto exit;
149
150 req->test_audio_period_ch_3 = ret;
151 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_3 = 0x%x\n", ret);
152
153 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH4);
154 if (ret == -EINVAL)
155 goto exit;
156
157 req->test_audio_period_ch_4 = ret;
158 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_4 = 0x%x\n", ret);
159
160 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH5);
161 if (ret == -EINVAL)
162 goto exit;
163
164 req->test_audio_period_ch_5 = ret;
165 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_5 = 0x%x\n", ret);
166
167 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH6);
168 if (ret == -EINVAL)
169 goto exit;
170
171 req->test_audio_period_ch_6 = ret;
172 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_6 = 0x%x\n", ret);
173
174 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH7);
175 if (ret == -EINVAL)
176 goto exit;
177
178 req->test_audio_period_ch_7 = ret;
179 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_7 = 0x%x\n", ret);
180
181 ret = dp_link_get_period(link, DP_TEST_AUDIO_PERIOD_CH8);
182 if (ret == -EINVAL)
183 goto exit;
184
185 req->test_audio_period_ch_8 = ret;
186 drm_dbg_dp(link->drm_dev, "test_audio_period_ch_8 = 0x%x\n", ret);
187exit:
188 return ret;
189}
190
191static int dp_link_parse_audio_pattern_type(struct dp_link_private *link)
192{
193 int ret = 0;
194 u8 data;
195 ssize_t rlen;
196 int const max_audio_pattern_type = 0x1;
197
198 rlen = drm_dp_dpcd_readb(aux: link->aux,
199 DP_TEST_AUDIO_PATTERN_TYPE, valuep: &data);
200 if (rlen < 0) {
201 DRM_ERROR("failed to read link audio mode. rlen=%zd\n", rlen);
202 return rlen;
203 }
204
205 /* Audio Pattern Type - Bits 7:0 */
206 if ((int)data > max_audio_pattern_type) {
207 DRM_ERROR("invalid audio pattern type = 0x%x\n", data);
208 ret = -EINVAL;
209 goto exit;
210 }
211
212 link->dp_link.test_audio.test_audio_pattern_type = data;
213 drm_dbg_dp(link->drm_dev, "audio pattern type = 0x%x\n", data);
214exit:
215 return ret;
216}
217
218static int dp_link_parse_audio_mode(struct dp_link_private *link)
219{
220 int ret = 0;
221 u8 data;
222 ssize_t rlen;
223 int const max_audio_sampling_rate = 0x6;
224 int const max_audio_channel_count = 0x8;
225 int sampling_rate = 0x0;
226 int channel_count = 0x0;
227
228 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_TEST_AUDIO_MODE, valuep: &data);
229 if (rlen < 0) {
230 DRM_ERROR("failed to read link audio mode. rlen=%zd\n", rlen);
231 return rlen;
232 }
233
234 /* Sampling Rate - Bits 3:0 */
235 sampling_rate = data & 0xF;
236 if (sampling_rate > max_audio_sampling_rate) {
237 DRM_ERROR("sampling rate (0x%x) greater than max (0x%x)\n",
238 sampling_rate, max_audio_sampling_rate);
239 ret = -EINVAL;
240 goto exit;
241 }
242
243 /* Channel Count - Bits 7:4 */
244 channel_count = ((data & 0xF0) >> 4) + 1;
245 if (channel_count > max_audio_channel_count) {
246 DRM_ERROR("channel_count (0x%x) greater than max (0x%x)\n",
247 channel_count, max_audio_channel_count);
248 ret = -EINVAL;
249 goto exit;
250 }
251
252 link->dp_link.test_audio.test_audio_sampling_rate = sampling_rate;
253 link->dp_link.test_audio.test_audio_channel_count = channel_count;
254 drm_dbg_dp(link->drm_dev,
255 "sampling_rate = 0x%x, channel_count = 0x%x\n",
256 sampling_rate, channel_count);
257exit:
258 return ret;
259}
260
261static int dp_link_parse_audio_pattern_params(struct dp_link_private *link)
262{
263 int ret = 0;
264
265 ret = dp_link_parse_audio_mode(link);
266 if (ret)
267 goto exit;
268
269 ret = dp_link_parse_audio_pattern_type(link);
270 if (ret)
271 goto exit;
272
273 ret = dp_link_parse_audio_channel_period(link);
274
275exit:
276 return ret;
277}
278
279static bool dp_link_is_video_pattern_valid(u32 pattern)
280{
281 switch (pattern) {
282 case DP_NO_TEST_PATTERN:
283 case DP_COLOR_RAMP:
284 case DP_BLACK_AND_WHITE_VERTICAL_LINES:
285 case DP_COLOR_SQUARE:
286 return true;
287 default:
288 return false;
289 }
290}
291
292/**
293 * dp_link_is_bit_depth_valid() - validates the bit depth requested
294 * @tbd: bit depth requested by the sink
295 *
296 * Returns true if the requested bit depth is supported.
297 */
298static bool dp_link_is_bit_depth_valid(u32 tbd)
299{
300 /* DP_TEST_VIDEO_PATTERN_NONE is treated as invalid */
301 switch (tbd) {
302 case DP_TEST_BIT_DEPTH_6:
303 case DP_TEST_BIT_DEPTH_8:
304 case DP_TEST_BIT_DEPTH_10:
305 return true;
306 default:
307 return false;
308 }
309}
310
311static int dp_link_parse_timing_params1(struct dp_link_private *link,
312 int addr, int len, u32 *val)
313{
314 u8 bp[2];
315 int rlen;
316
317 if (len != 2)
318 return -EINVAL;
319
320 /* Read the requested video link pattern (Byte 0x221). */
321 rlen = drm_dp_dpcd_read(aux: link->aux, offset: addr, buffer: bp, size: len);
322 if (rlen < len) {
323 DRM_ERROR("failed to read 0x%x\n", addr);
324 return -EINVAL;
325 }
326
327 *val = bp[1] | (bp[0] << 8);
328
329 return 0;
330}
331
332static int dp_link_parse_timing_params2(struct dp_link_private *link,
333 int addr, int len,
334 u32 *val1, u32 *val2)
335{
336 u8 bp[2];
337 int rlen;
338
339 if (len != 2)
340 return -EINVAL;
341
342 /* Read the requested video link pattern (Byte 0x221). */
343 rlen = drm_dp_dpcd_read(aux: link->aux, offset: addr, buffer: bp, size: len);
344 if (rlen < len) {
345 DRM_ERROR("failed to read 0x%x\n", addr);
346 return -EINVAL;
347 }
348
349 *val1 = (bp[0] & BIT(7)) >> 7;
350 *val2 = bp[1] | ((bp[0] & 0x7F) << 8);
351
352 return 0;
353}
354
355static int dp_link_parse_timing_params3(struct dp_link_private *link,
356 int addr, u32 *val)
357{
358 u8 bp;
359 u32 len = 1;
360 int rlen;
361
362 rlen = drm_dp_dpcd_read(aux: link->aux, offset: addr, buffer: &bp, size: len);
363 if (rlen < 1) {
364 DRM_ERROR("failed to read 0x%x\n", addr);
365 return -EINVAL;
366 }
367 *val = bp;
368
369 return 0;
370}
371
372/**
373 * dp_link_parse_video_pattern_params() - parses video pattern parameters from DPCD
374 * @link: Display Port Driver data
375 *
376 * Returns 0 if it successfully parses the video link pattern and the link
377 * bit depth requested by the sink and, and if the values parsed are valid.
378 */
379static int dp_link_parse_video_pattern_params(struct dp_link_private *link)
380{
381 int ret = 0;
382 ssize_t rlen;
383 u8 bp;
384
385 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_TEST_PATTERN, valuep: &bp);
386 if (rlen < 0) {
387 DRM_ERROR("failed to read link video pattern. rlen=%zd\n",
388 rlen);
389 return rlen;
390 }
391
392 if (!dp_link_is_video_pattern_valid(pattern: bp)) {
393 DRM_ERROR("invalid link video pattern = 0x%x\n", bp);
394 ret = -EINVAL;
395 return ret;
396 }
397
398 link->dp_link.test_video.test_video_pattern = bp;
399
400 /* Read the requested color bit depth and dynamic range (Byte 0x232) */
401 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_TEST_MISC0, valuep: &bp);
402 if (rlen < 0) {
403 DRM_ERROR("failed to read link bit depth. rlen=%zd\n", rlen);
404 return rlen;
405 }
406
407 /* Dynamic Range */
408 link->dp_link.test_video.test_dyn_range =
409 (bp & DP_TEST_DYNAMIC_RANGE_CEA);
410
411 /* Color bit depth */
412 bp &= DP_TEST_BIT_DEPTH_MASK;
413 if (!dp_link_is_bit_depth_valid(tbd: bp)) {
414 DRM_ERROR("invalid link bit depth = 0x%x\n", bp);
415 ret = -EINVAL;
416 return ret;
417 }
418
419 link->dp_link.test_video.test_bit_depth = bp;
420
421 /* resolution timing params */
422 ret = dp_link_parse_timing_params1(link, DP_TEST_H_TOTAL_HI, len: 2,
423 val: &link->dp_link.test_video.test_h_total);
424 if (ret) {
425 DRM_ERROR("failed to parse test_htotal(DP_TEST_H_TOTAL_HI)\n");
426 return ret;
427 }
428
429 ret = dp_link_parse_timing_params1(link, DP_TEST_V_TOTAL_HI, len: 2,
430 val: &link->dp_link.test_video.test_v_total);
431 if (ret) {
432 DRM_ERROR("failed to parse test_v_total(DP_TEST_V_TOTAL_HI)\n");
433 return ret;
434 }
435
436 ret = dp_link_parse_timing_params1(link, DP_TEST_H_START_HI, len: 2,
437 val: &link->dp_link.test_video.test_h_start);
438 if (ret) {
439 DRM_ERROR("failed to parse test_h_start(DP_TEST_H_START_HI)\n");
440 return ret;
441 }
442
443 ret = dp_link_parse_timing_params1(link, DP_TEST_V_START_HI, len: 2,
444 val: &link->dp_link.test_video.test_v_start);
445 if (ret) {
446 DRM_ERROR("failed to parse test_v_start(DP_TEST_V_START_HI)\n");
447 return ret;
448 }
449
450 ret = dp_link_parse_timing_params2(link, DP_TEST_HSYNC_HI, len: 2,
451 val1: &link->dp_link.test_video.test_hsync_pol,
452 val2: &link->dp_link.test_video.test_hsync_width);
453 if (ret) {
454 DRM_ERROR("failed to parse (DP_TEST_HSYNC_HI)\n");
455 return ret;
456 }
457
458 ret = dp_link_parse_timing_params2(link, DP_TEST_VSYNC_HI, len: 2,
459 val1: &link->dp_link.test_video.test_vsync_pol,
460 val2: &link->dp_link.test_video.test_vsync_width);
461 if (ret) {
462 DRM_ERROR("failed to parse (DP_TEST_VSYNC_HI)\n");
463 return ret;
464 }
465
466 ret = dp_link_parse_timing_params1(link, DP_TEST_H_WIDTH_HI, len: 2,
467 val: &link->dp_link.test_video.test_h_width);
468 if (ret) {
469 DRM_ERROR("failed to parse test_h_width(DP_TEST_H_WIDTH_HI)\n");
470 return ret;
471 }
472
473 ret = dp_link_parse_timing_params1(link, DP_TEST_V_HEIGHT_HI, len: 2,
474 val: &link->dp_link.test_video.test_v_height);
475 if (ret) {
476 DRM_ERROR("failed to parse test_v_height\n");
477 return ret;
478 }
479
480 ret = dp_link_parse_timing_params3(link, DP_TEST_MISC1,
481 val: &link->dp_link.test_video.test_rr_d);
482 link->dp_link.test_video.test_rr_d &= DP_TEST_REFRESH_DENOMINATOR;
483 if (ret) {
484 DRM_ERROR("failed to parse test_rr_d (DP_TEST_MISC1)\n");
485 return ret;
486 }
487
488 ret = dp_link_parse_timing_params3(link, DP_TEST_REFRESH_RATE_NUMERATOR,
489 val: &link->dp_link.test_video.test_rr_n);
490 if (ret) {
491 DRM_ERROR("failed to parse test_rr_n\n");
492 return ret;
493 }
494
495 drm_dbg_dp(link->drm_dev,
496 "link video pattern = 0x%x\n"
497 "link dynamic range = 0x%x\n"
498 "link bit depth = 0x%x\n"
499 "TEST_H_TOTAL = %d, TEST_V_TOTAL = %d\n"
500 "TEST_H_START = %d, TEST_V_START = %d\n"
501 "TEST_HSYNC_POL = %d\n"
502 "TEST_HSYNC_WIDTH = %d\n"
503 "TEST_VSYNC_POL = %d\n"
504 "TEST_VSYNC_WIDTH = %d\n"
505 "TEST_H_WIDTH = %d\n"
506 "TEST_V_HEIGHT = %d\n"
507 "TEST_REFRESH_DENOMINATOR = %d\n"
508 "TEST_REFRESH_NUMERATOR = %d\n",
509 link->dp_link.test_video.test_video_pattern,
510 link->dp_link.test_video.test_dyn_range,
511 link->dp_link.test_video.test_bit_depth,
512 link->dp_link.test_video.test_h_total,
513 link->dp_link.test_video.test_v_total,
514 link->dp_link.test_video.test_h_start,
515 link->dp_link.test_video.test_v_start,
516 link->dp_link.test_video.test_hsync_pol,
517 link->dp_link.test_video.test_hsync_width,
518 link->dp_link.test_video.test_vsync_pol,
519 link->dp_link.test_video.test_vsync_width,
520 link->dp_link.test_video.test_h_width,
521 link->dp_link.test_video.test_v_height,
522 link->dp_link.test_video.test_rr_d,
523 link->dp_link.test_video.test_rr_n);
524
525 return ret;
526}
527
528/**
529 * dp_link_parse_link_training_params() - parses link training parameters from
530 * DPCD
531 * @link: Display Port Driver data
532 *
533 * Returns 0 if it successfully parses the link rate (Byte 0x219) and lane
534 * count (Byte 0x220), and if these values parse are valid.
535 */
536static int dp_link_parse_link_training_params(struct dp_link_private *link)
537{
538 u8 bp;
539 ssize_t rlen;
540
541 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_TEST_LINK_RATE, valuep: &bp);
542 if (rlen < 0) {
543 DRM_ERROR("failed to read link rate. rlen=%zd\n", rlen);
544 return rlen;
545 }
546
547 if (!is_link_rate_valid(bw_code: bp)) {
548 DRM_ERROR("invalid link rate = 0x%x\n", bp);
549 return -EINVAL;
550 }
551
552 link->request.test_link_rate = bp;
553 drm_dbg_dp(link->drm_dev, "link rate = 0x%x\n",
554 link->request.test_link_rate);
555
556 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_TEST_LANE_COUNT, valuep: &bp);
557 if (rlen < 0) {
558 DRM_ERROR("failed to read lane count. rlen=%zd\n", rlen);
559 return rlen;
560 }
561 bp &= DP_MAX_LANE_COUNT_MASK;
562
563 if (!is_lane_count_valid(lane_count: bp)) {
564 DRM_ERROR("invalid lane count = 0x%x\n", bp);
565 return -EINVAL;
566 }
567
568 link->request.test_lane_count = bp;
569 drm_dbg_dp(link->drm_dev, "lane count = 0x%x\n",
570 link->request.test_lane_count);
571 return 0;
572}
573
574/**
575 * dp_link_parse_phy_test_params() - parses the phy link parameters
576 * @link: Display Port Driver data
577 *
578 * Parses the DPCD (Byte 0x248) for the DP PHY link pattern that is being
579 * requested.
580 */
581static int dp_link_parse_phy_test_params(struct dp_link_private *link)
582{
583 u8 data;
584 ssize_t rlen;
585
586 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_PHY_TEST_PATTERN,
587 valuep: &data);
588 if (rlen < 0) {
589 DRM_ERROR("failed to read phy link pattern. rlen=%zd\n", rlen);
590 return rlen;
591 }
592
593 link->dp_link.phy_params.phy_test_pattern_sel = data & 0x07;
594
595 drm_dbg_dp(link->drm_dev, "phy_test_pattern_sel = 0x%x\n", data);
596
597 switch (data) {
598 case DP_PHY_TEST_PATTERN_SEL_MASK:
599 case DP_PHY_TEST_PATTERN_NONE:
600 case DP_PHY_TEST_PATTERN_D10_2:
601 case DP_PHY_TEST_PATTERN_ERROR_COUNT:
602 case DP_PHY_TEST_PATTERN_PRBS7:
603 case DP_PHY_TEST_PATTERN_80BIT_CUSTOM:
604 case DP_PHY_TEST_PATTERN_CP2520:
605 return 0;
606 default:
607 return -EINVAL;
608 }
609}
610
611/**
612 * dp_link_is_video_audio_test_requested() - checks for audio/video link request
613 * @link: link requested by the sink
614 *
615 * Returns true if the requested link is a permitted audio/video link.
616 */
617static bool dp_link_is_video_audio_test_requested(u32 link)
618{
619 u8 video_audio_test = (DP_TEST_LINK_VIDEO_PATTERN |
620 DP_TEST_LINK_AUDIO_PATTERN |
621 DP_TEST_LINK_AUDIO_DISABLED_VIDEO);
622
623 return ((link & video_audio_test) &&
624 !(link & ~video_audio_test));
625}
626
627/**
628 * dp_link_parse_request() - parses link request parameters from sink
629 * @link: Display Port Driver data
630 *
631 * Parses the DPCD to check if an automated link is requested (Byte 0x201),
632 * and what type of link automation is being requested (Byte 0x218).
633 */
634static int dp_link_parse_request(struct dp_link_private *link)
635{
636 int ret = 0;
637 u8 data;
638 ssize_t rlen;
639
640 /**
641 * Read the device service IRQ vector (Byte 0x201) to determine
642 * whether an automated link has been requested by the sink.
643 */
644 rlen = drm_dp_dpcd_readb(aux: link->aux,
645 DP_DEVICE_SERVICE_IRQ_VECTOR, valuep: &data);
646 if (rlen < 0) {
647 DRM_ERROR("aux read failed. rlen=%zd\n", rlen);
648 return rlen;
649 }
650
651 drm_dbg_dp(link->drm_dev, "device service irq vector = 0x%x\n", data);
652
653 if (!(data & DP_AUTOMATED_TEST_REQUEST)) {
654 drm_dbg_dp(link->drm_dev, "no test requested\n");
655 return 0;
656 }
657
658 /**
659 * Read the link request byte (Byte 0x218) to determine what type
660 * of automated link has been requested by the sink.
661 */
662 rlen = drm_dp_dpcd_readb(aux: link->aux, DP_TEST_REQUEST, valuep: &data);
663 if (rlen < 0) {
664 DRM_ERROR("aux read failed. rlen=%zd\n", rlen);
665 return rlen;
666 }
667
668 if (!data || (data == DP_TEST_LINK_FAUX_PATTERN)) {
669 drm_dbg_dp(link->drm_dev, "link 0x%x not supported\n", data);
670 goto end;
671 }
672
673 drm_dbg_dp(link->drm_dev, "Test:(0x%x) requested\n", data);
674 link->request.test_requested = data;
675 if (link->request.test_requested == DP_TEST_LINK_PHY_TEST_PATTERN) {
676 ret = dp_link_parse_phy_test_params(link);
677 if (ret)
678 goto end;
679 ret = dp_link_parse_link_training_params(link);
680 if (ret)
681 goto end;
682 }
683
684 if (link->request.test_requested == DP_TEST_LINK_TRAINING) {
685 ret = dp_link_parse_link_training_params(link);
686 if (ret)
687 goto end;
688 }
689
690 if (dp_link_is_video_audio_test_requested(
691 link: link->request.test_requested)) {
692 ret = dp_link_parse_video_pattern_params(link);
693 if (ret)
694 goto end;
695
696 ret = dp_link_parse_audio_pattern_params(link);
697 }
698end:
699 /*
700 * Send a DP_TEST_ACK if all link parameters are valid, otherwise send
701 * a DP_TEST_NAK.
702 */
703 if (ret) {
704 link->dp_link.test_response = DP_TEST_NAK;
705 } else {
706 if (link->request.test_requested != DP_TEST_LINK_EDID_READ)
707 link->dp_link.test_response = DP_TEST_ACK;
708 else
709 link->dp_link.test_response =
710 DP_TEST_EDID_CHECKSUM_WRITE;
711 }
712
713 return ret;
714}
715
716static int dp_link_parse_sink_status_field(struct dp_link_private *link)
717{
718 int len;
719
720 link->prev_sink_count = link->dp_link.sink_count;
721 len = drm_dp_read_sink_count(aux: link->aux);
722 if (len < 0) {
723 DRM_ERROR("DP parse sink count failed\n");
724 return len;
725 }
726 link->dp_link.sink_count = len;
727
728 len = drm_dp_dpcd_read_link_status(aux: link->aux,
729 status: link->link_status);
730 if (len < DP_LINK_STATUS_SIZE) {
731 DRM_ERROR("DP link status read failed\n");
732 return len;
733 }
734
735 return dp_link_parse_request(link);
736}
737
738/**
739 * dp_link_process_link_training_request() - processes new training requests
740 * @link: Display Port link data
741 *
742 * This function will handle new link training requests that are initiated by
743 * the sink. In particular, it will update the requested lane count and link
744 * rate, and then trigger the link retraining procedure.
745 *
746 * The function will return 0 if a link training request has been processed,
747 * otherwise it will return -EINVAL.
748 */
749static int dp_link_process_link_training_request(struct dp_link_private *link)
750{
751 if (link->request.test_requested != DP_TEST_LINK_TRAINING)
752 return -EINVAL;
753
754 drm_dbg_dp(link->drm_dev,
755 "Test:0x%x link rate = 0x%x, lane count = 0x%x\n",
756 DP_TEST_LINK_TRAINING,
757 link->request.test_link_rate,
758 link->request.test_lane_count);
759
760 link->dp_link.link_params.num_lanes = link->request.test_lane_count;
761 link->dp_link.link_params.rate =
762 drm_dp_bw_code_to_link_rate(link_bw: link->request.test_link_rate);
763
764 return 0;
765}
766
767bool dp_link_send_test_response(struct dp_link *dp_link)
768{
769 struct dp_link_private *link = NULL;
770 int ret = 0;
771
772 if (!dp_link) {
773 DRM_ERROR("invalid input\n");
774 return false;
775 }
776
777 link = container_of(dp_link, struct dp_link_private, dp_link);
778
779 ret = drm_dp_dpcd_writeb(aux: link->aux, DP_TEST_RESPONSE,
780 value: dp_link->test_response);
781
782 return ret == 1;
783}
784
785int dp_link_psm_config(struct dp_link *dp_link,
786 struct dp_link_info *link_info, bool enable)
787{
788 struct dp_link_private *link = NULL;
789 int ret = 0;
790
791 if (!dp_link) {
792 DRM_ERROR("invalid params\n");
793 return -EINVAL;
794 }
795
796 link = container_of(dp_link, struct dp_link_private, dp_link);
797
798 mutex_lock(&link->psm_mutex);
799 if (enable)
800 ret = dp_aux_link_power_down(aux: link->aux, link: link_info);
801 else
802 ret = dp_aux_link_power_up(aux: link->aux, link: link_info);
803
804 if (ret)
805 DRM_ERROR("Failed to %s low power mode\n", enable ?
806 "enter" : "exit");
807 else
808 dp_link->psm_enabled = enable;
809
810 mutex_unlock(lock: &link->psm_mutex);
811 return ret;
812}
813
814bool dp_link_send_edid_checksum(struct dp_link *dp_link, u8 checksum)
815{
816 struct dp_link_private *link = NULL;
817 int ret = 0;
818
819 if (!dp_link) {
820 DRM_ERROR("invalid input\n");
821 return false;
822 }
823
824 link = container_of(dp_link, struct dp_link_private, dp_link);
825
826 ret = drm_dp_dpcd_writeb(aux: link->aux, DP_TEST_EDID_CHECKSUM,
827 value: checksum);
828 return ret == 1;
829}
830
831static void dp_link_parse_vx_px(struct dp_link_private *link)
832{
833 drm_dbg_dp(link->drm_dev, "vx: 0=%d, 1=%d, 2=%d, 3=%d\n",
834 drm_dp_get_adjust_request_voltage(link->link_status, 0),
835 drm_dp_get_adjust_request_voltage(link->link_status, 1),
836 drm_dp_get_adjust_request_voltage(link->link_status, 2),
837 drm_dp_get_adjust_request_voltage(link->link_status, 3));
838
839 drm_dbg_dp(link->drm_dev, "px: 0=%d, 1=%d, 2=%d, 3=%d\n",
840 drm_dp_get_adjust_request_pre_emphasis(link->link_status, 0),
841 drm_dp_get_adjust_request_pre_emphasis(link->link_status, 1),
842 drm_dp_get_adjust_request_pre_emphasis(link->link_status, 2),
843 drm_dp_get_adjust_request_pre_emphasis(link->link_status, 3));
844
845 /**
846 * Update the voltage and pre-emphasis levels as per DPCD request
847 * vector.
848 */
849 drm_dbg_dp(link->drm_dev,
850 "Current: v_level = 0x%x, p_level = 0x%x\n",
851 link->dp_link.phy_params.v_level,
852 link->dp_link.phy_params.p_level);
853 link->dp_link.phy_params.v_level =
854 drm_dp_get_adjust_request_voltage(link_status: link->link_status, lane: 0);
855 link->dp_link.phy_params.p_level =
856 drm_dp_get_adjust_request_pre_emphasis(link_status: link->link_status, lane: 0);
857
858 link->dp_link.phy_params.p_level >>= DP_TRAIN_PRE_EMPHASIS_SHIFT;
859
860 drm_dbg_dp(link->drm_dev,
861 "Requested: v_level = 0x%x, p_level = 0x%x\n",
862 link->dp_link.phy_params.v_level,
863 link->dp_link.phy_params.p_level);
864}
865
866/**
867 * dp_link_process_phy_test_pattern_request() - process new phy link requests
868 * @link: Display Port Driver data
869 *
870 * This function will handle new phy link pattern requests that are initiated
871 * by the sink. The function will return 0 if a phy link pattern has been
872 * processed, otherwise it will return -EINVAL.
873 */
874static int dp_link_process_phy_test_pattern_request(
875 struct dp_link_private *link)
876{
877 if (!(link->request.test_requested & DP_TEST_LINK_PHY_TEST_PATTERN)) {
878 drm_dbg_dp(link->drm_dev, "no phy test\n");
879 return -EINVAL;
880 }
881
882 if (!is_link_rate_valid(bw_code: link->request.test_link_rate) ||
883 !is_lane_count_valid(lane_count: link->request.test_lane_count)) {
884 DRM_ERROR("Invalid: link rate = 0x%x,lane count = 0x%x\n",
885 link->request.test_link_rate,
886 link->request.test_lane_count);
887 return -EINVAL;
888 }
889
890 drm_dbg_dp(link->drm_dev,
891 "Current: rate = 0x%x, lane count = 0x%x\n",
892 link->dp_link.link_params.rate,
893 link->dp_link.link_params.num_lanes);
894
895 drm_dbg_dp(link->drm_dev,
896 "Requested: rate = 0x%x, lane count = 0x%x\n",
897 link->request.test_link_rate,
898 link->request.test_lane_count);
899
900 link->dp_link.link_params.num_lanes = link->request.test_lane_count;
901 link->dp_link.link_params.rate =
902 drm_dp_bw_code_to_link_rate(link_bw: link->request.test_link_rate);
903
904 dp_link_parse_vx_px(link);
905
906 return 0;
907}
908
909static bool dp_link_read_psr_error_status(struct dp_link_private *link)
910{
911 u8 status;
912
913 drm_dp_dpcd_read(aux: link->aux, DP_PSR_ERROR_STATUS, buffer: &status, size: 1);
914
915 if (status & DP_PSR_LINK_CRC_ERROR)
916 DRM_ERROR("PSR LINK CRC ERROR\n");
917 else if (status & DP_PSR_RFB_STORAGE_ERROR)
918 DRM_ERROR("PSR RFB STORAGE ERROR\n");
919 else if (status & DP_PSR_VSC_SDP_UNCORRECTABLE_ERROR)
920 DRM_ERROR("PSR VSC SDP UNCORRECTABLE ERROR\n");
921 else
922 return false;
923
924 return true;
925}
926
927static bool dp_link_psr_capability_changed(struct dp_link_private *link)
928{
929 u8 status;
930
931 drm_dp_dpcd_read(aux: link->aux, DP_PSR_ESI, buffer: &status, size: 1);
932
933 if (status & DP_PSR_CAPS_CHANGE) {
934 drm_dbg_dp(link->drm_dev, "PSR Capability Change\n");
935 return true;
936 }
937
938 return false;
939}
940
941static u8 get_link_status(const u8 link_status[DP_LINK_STATUS_SIZE], int r)
942{
943 return link_status[r - DP_LANE0_1_STATUS];
944}
945
946/**
947 * dp_link_process_link_status_update() - processes link status updates
948 * @link: Display Port link module data
949 *
950 * This function will check for changes in the link status, e.g. clock
951 * recovery done on all lanes, and trigger link training if there is a
952 * failure/error on the link.
953 *
954 * The function will return 0 if the a link status update has been processed,
955 * otherwise it will return -EINVAL.
956 */
957static int dp_link_process_link_status_update(struct dp_link_private *link)
958{
959 bool channel_eq_done = drm_dp_channel_eq_ok(link_status: link->link_status,
960 lane_count: link->dp_link.link_params.num_lanes);
961
962 bool clock_recovery_done = drm_dp_clock_recovery_ok(link_status: link->link_status,
963 lane_count: link->dp_link.link_params.num_lanes);
964
965 drm_dbg_dp(link->drm_dev,
966 "channel_eq_done = %d, clock_recovery_done = %d\n",
967 channel_eq_done, clock_recovery_done);
968
969 if (channel_eq_done && clock_recovery_done)
970 return -EINVAL;
971
972 return 0;
973}
974
975/**
976 * dp_link_process_ds_port_status_change() - process port status changes
977 * @link: Display Port Driver data
978 *
979 * This function will handle downstream port updates that are initiated by
980 * the sink. If the downstream port status has changed, the EDID is read via
981 * AUX.
982 *
983 * The function will return 0 if a downstream port update has been
984 * processed, otherwise it will return -EINVAL.
985 */
986static int dp_link_process_ds_port_status_change(struct dp_link_private *link)
987{
988 if (get_link_status(link_status: link->link_status, DP_LANE_ALIGN_STATUS_UPDATED) &
989 DP_DOWNSTREAM_PORT_STATUS_CHANGED)
990 goto reset;
991
992 if (link->prev_sink_count == link->dp_link.sink_count)
993 return -EINVAL;
994
995reset:
996 /* reset prev_sink_count */
997 link->prev_sink_count = link->dp_link.sink_count;
998
999 return 0;
1000}
1001
1002static bool dp_link_is_video_pattern_requested(struct dp_link_private *link)
1003{
1004 return (link->request.test_requested & DP_TEST_LINK_VIDEO_PATTERN)
1005 && !(link->request.test_requested &
1006 DP_TEST_LINK_AUDIO_DISABLED_VIDEO);
1007}
1008
1009static bool dp_link_is_audio_pattern_requested(struct dp_link_private *link)
1010{
1011 return (link->request.test_requested & DP_TEST_LINK_AUDIO_PATTERN);
1012}
1013
1014static void dp_link_reset_data(struct dp_link_private *link)
1015{
1016 link->request = (const struct dp_link_request){ 0 };
1017 link->dp_link.test_video = (const struct dp_link_test_video){ 0 };
1018 link->dp_link.test_video.test_bit_depth = DP_TEST_BIT_DEPTH_UNKNOWN;
1019 link->dp_link.test_audio = (const struct dp_link_test_audio){ 0 };
1020 link->dp_link.phy_params.phy_test_pattern_sel = 0;
1021 link->dp_link.sink_request = 0;
1022 link->dp_link.test_response = 0;
1023}
1024
1025/**
1026 * dp_link_process_request() - handle HPD IRQ transition to HIGH
1027 * @dp_link: pointer to link module data
1028 *
1029 * This function will handle the HPD IRQ state transitions from LOW to HIGH
1030 * (including cases when there are back to back HPD IRQ HIGH) indicating
1031 * the start of a new link training request or sink status update.
1032 */
1033int dp_link_process_request(struct dp_link *dp_link)
1034{
1035 int ret = 0;
1036 struct dp_link_private *link;
1037
1038 if (!dp_link) {
1039 DRM_ERROR("invalid input\n");
1040 return -EINVAL;
1041 }
1042
1043 link = container_of(dp_link, struct dp_link_private, dp_link);
1044
1045 dp_link_reset_data(link);
1046
1047 ret = dp_link_parse_sink_status_field(link);
1048 if (ret)
1049 return ret;
1050
1051 if (link->request.test_requested == DP_TEST_LINK_EDID_READ) {
1052 dp_link->sink_request |= DP_TEST_LINK_EDID_READ;
1053 } else if (!dp_link_process_ds_port_status_change(link)) {
1054 dp_link->sink_request |= DS_PORT_STATUS_CHANGED;
1055 } else if (!dp_link_process_link_training_request(link)) {
1056 dp_link->sink_request |= DP_TEST_LINK_TRAINING;
1057 } else if (!dp_link_process_phy_test_pattern_request(link)) {
1058 dp_link->sink_request |= DP_TEST_LINK_PHY_TEST_PATTERN;
1059 } else if (dp_link_read_psr_error_status(link)) {
1060 DRM_ERROR("PSR IRQ_HPD received\n");
1061 } else if (dp_link_psr_capability_changed(link)) {
1062 drm_dbg_dp(link->drm_dev, "PSR Capability changed\n");
1063 } else {
1064 ret = dp_link_process_link_status_update(link);
1065 if (!ret) {
1066 dp_link->sink_request |= DP_LINK_STATUS_UPDATED;
1067 } else {
1068 if (dp_link_is_video_pattern_requested(link)) {
1069 ret = 0;
1070 dp_link->sink_request |= DP_TEST_LINK_VIDEO_PATTERN;
1071 }
1072 if (dp_link_is_audio_pattern_requested(link)) {
1073 dp_link->sink_request |= DP_TEST_LINK_AUDIO_PATTERN;
1074 ret = -EINVAL;
1075 }
1076 }
1077 }
1078
1079 drm_dbg_dp(link->drm_dev, "sink request=%#x\n",
1080 dp_link->sink_request);
1081 return ret;
1082}
1083
1084int dp_link_get_colorimetry_config(struct dp_link *dp_link)
1085{
1086 u32 cc = DP_MISC0_COLORIMERY_CFG_LEGACY_RGB;
1087 struct dp_link_private *link;
1088
1089 if (!dp_link) {
1090 DRM_ERROR("invalid input\n");
1091 return -EINVAL;
1092 }
1093
1094 link = container_of(dp_link, struct dp_link_private, dp_link);
1095
1096 /*
1097 * Unless a video pattern CTS test is ongoing, use RGB_VESA
1098 * Only RGB_VESA and RGB_CEA supported for now
1099 */
1100 if (dp_link_is_video_pattern_requested(link)) {
1101 if (link->dp_link.test_video.test_dyn_range &
1102 DP_TEST_DYNAMIC_RANGE_CEA)
1103 cc = DP_MISC0_COLORIMERY_CFG_CEA_RGB;
1104 }
1105
1106 return cc;
1107}
1108
1109int dp_link_adjust_levels(struct dp_link *dp_link, u8 *link_status)
1110{
1111 int i;
1112 int v_max = 0, p_max = 0;
1113 struct dp_link_private *link;
1114
1115 if (!dp_link) {
1116 DRM_ERROR("invalid input\n");
1117 return -EINVAL;
1118 }
1119
1120 link = container_of(dp_link, struct dp_link_private, dp_link);
1121
1122 /* use the max level across lanes */
1123 for (i = 0; i < dp_link->link_params.num_lanes; i++) {
1124 u8 data_v = drm_dp_get_adjust_request_voltage(link_status, lane: i);
1125 u8 data_p = drm_dp_get_adjust_request_pre_emphasis(link_status,
1126 lane: i);
1127 drm_dbg_dp(link->drm_dev,
1128 "lane=%d req_vol_swing=%d req_pre_emphasis=%d\n",
1129 i, data_v, data_p);
1130 if (v_max < data_v)
1131 v_max = data_v;
1132 if (p_max < data_p)
1133 p_max = data_p;
1134 }
1135
1136 dp_link->phy_params.v_level = v_max >> DP_TRAIN_VOLTAGE_SWING_SHIFT;
1137 dp_link->phy_params.p_level = p_max >> DP_TRAIN_PRE_EMPHASIS_SHIFT;
1138
1139 /**
1140 * Adjust the voltage swing and pre-emphasis level combination to within
1141 * the allowable range.
1142 */
1143 if (dp_link->phy_params.v_level > DP_TRAIN_VOLTAGE_SWING_MAX) {
1144 drm_dbg_dp(link->drm_dev,
1145 "Requested vSwingLevel=%d, change to %d\n",
1146 dp_link->phy_params.v_level,
1147 DP_TRAIN_VOLTAGE_SWING_MAX);
1148 dp_link->phy_params.v_level = DP_TRAIN_VOLTAGE_SWING_MAX;
1149 }
1150
1151 if (dp_link->phy_params.p_level > DP_TRAIN_PRE_EMPHASIS_MAX) {
1152 drm_dbg_dp(link->drm_dev,
1153 "Requested preEmphasisLevel=%d, change to %d\n",
1154 dp_link->phy_params.p_level,
1155 DP_TRAIN_PRE_EMPHASIS_MAX);
1156 dp_link->phy_params.p_level = DP_TRAIN_PRE_EMPHASIS_MAX;
1157 }
1158
1159 if ((dp_link->phy_params.p_level > DP_TRAIN_PRE_EMPHASIS_LVL_1)
1160 && (dp_link->phy_params.v_level ==
1161 DP_TRAIN_VOLTAGE_SWING_LVL_2)) {
1162 drm_dbg_dp(link->drm_dev,
1163 "Requested preEmphasisLevel=%d, change to %d\n",
1164 dp_link->phy_params.p_level,
1165 DP_TRAIN_PRE_EMPHASIS_LVL_1);
1166 dp_link->phy_params.p_level = DP_TRAIN_PRE_EMPHASIS_LVL_1;
1167 }
1168
1169 drm_dbg_dp(link->drm_dev, "adjusted: v_level=%d, p_level=%d\n",
1170 dp_link->phy_params.v_level, dp_link->phy_params.p_level);
1171
1172 return 0;
1173}
1174
1175void dp_link_reset_phy_params_vx_px(struct dp_link *dp_link)
1176{
1177 dp_link->phy_params.v_level = 0;
1178 dp_link->phy_params.p_level = 0;
1179}
1180
1181u32 dp_link_get_test_bits_depth(struct dp_link *dp_link, u32 bpp)
1182{
1183 u32 tbd;
1184 struct dp_link_private *link;
1185
1186 link = container_of(dp_link, struct dp_link_private, dp_link);
1187
1188 /*
1189 * Few simplistic rules and assumptions made here:
1190 * 1. Test bit depth is bit depth per color component
1191 * 2. Assume 3 color components
1192 */
1193 switch (bpp) {
1194 case 18:
1195 tbd = DP_TEST_BIT_DEPTH_6;
1196 break;
1197 case 24:
1198 tbd = DP_TEST_BIT_DEPTH_8;
1199 break;
1200 case 30:
1201 tbd = DP_TEST_BIT_DEPTH_10;
1202 break;
1203 default:
1204 drm_dbg_dp(link->drm_dev, "bpp=%d not supported, use bpc=8\n",
1205 bpp);
1206 tbd = DP_TEST_BIT_DEPTH_8;
1207 break;
1208 }
1209
1210 tbd = (tbd >> DP_TEST_BIT_DEPTH_SHIFT);
1211
1212 return tbd;
1213}
1214
1215struct dp_link *dp_link_get(struct device *dev, struct drm_dp_aux *aux)
1216{
1217 struct dp_link_private *link;
1218 struct dp_link *dp_link;
1219
1220 if (!dev || !aux) {
1221 DRM_ERROR("invalid input\n");
1222 return ERR_PTR(error: -EINVAL);
1223 }
1224
1225 link = devm_kzalloc(dev, size: sizeof(*link), GFP_KERNEL);
1226 if (!link)
1227 return ERR_PTR(error: -ENOMEM);
1228
1229 link->dev = dev;
1230 link->aux = aux;
1231
1232 mutex_init(&link->psm_mutex);
1233 dp_link = &link->dp_link;
1234
1235 return dp_link;
1236}
1237

source code of linux/drivers/gpu/drm/msm/dp/dp_link.c