xref: /linux/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Analogix DP (Display Port) core interface driver.
4 *
5 * Copyright (C) 2012 Samsung Electronics Co., Ltd.
6 * Author: Jingoo Han <jg1.han@samsung.com>
7 */
8 
9 #include <linux/clk.h>
10 #include <linux/component.h>
11 #include <linux/err.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/iopoll.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/phy/phy.h>
19 #include <linux/platform_device.h>
20 
21 #include <drm/bridge/analogix_dp.h>
22 #include <drm/drm_atomic.h>
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_crtc.h>
26 #include <drm/drm_device.h>
27 #include <drm/drm_edid.h>
28 #include <drm/drm_panel.h>
29 #include <drm/drm_print.h>
30 #include <drm/drm_probe_helper.h>
31 
32 #include "analogix_dp_core.h"
33 #include "analogix_dp_reg.h"
34 
35 #define to_dp(nm)	container_of(nm, struct analogix_dp_device, nm)
36 
37 static const bool verify_fast_training;
38 
analogix_dp_init_dp(struct analogix_dp_device * dp)39 static void analogix_dp_init_dp(struct analogix_dp_device *dp)
40 {
41 	analogix_dp_reset(dp);
42 
43 	analogix_dp_swreset(dp);
44 
45 	analogix_dp_init_analog_param(dp);
46 	analogix_dp_init_interrupt(dp);
47 
48 	/* SW defined function Normal operation */
49 	analogix_dp_enable_sw_function(dp);
50 
51 	analogix_dp_config_interrupt(dp);
52 
53 	analogix_dp_init_hpd(dp);
54 	analogix_dp_init_aux(dp);
55 }
56 
analogix_dp_detect_hpd(struct analogix_dp_device * dp)57 static int analogix_dp_detect_hpd(struct analogix_dp_device *dp)
58 {
59 	int timeout_loop = 0;
60 
61 	while (timeout_loop < DP_TIMEOUT_LOOP_COUNT) {
62 		if (analogix_dp_get_plug_in_status(dp) == 0)
63 			return 0;
64 
65 		timeout_loop++;
66 		usleep_range(1000, 1100);
67 	}
68 
69 	/*
70 	 * Some edp screen do not have hpd signal, so we can't just
71 	 * return failed when hpd plug in detect failed, DT property
72 	 * "force-hpd" would indicate whether driver need this.
73 	 */
74 	if (!dp->force_hpd)
75 		return -ETIMEDOUT;
76 
77 	/*
78 	 * The eDP TRM indicate that if HPD_STATUS(RO) is 0, AUX CH
79 	 * will not work, so we need to give a force hpd action to
80 	 * set HPD_STATUS manually.
81 	 */
82 	dev_dbg(dp->dev, "failed to get hpd plug status, try to force hpd\n");
83 
84 	analogix_dp_force_hpd(dp);
85 
86 	if (analogix_dp_get_plug_in_status(dp) != 0) {
87 		dev_err(dp->dev, "failed to get hpd plug in status\n");
88 		return -EINVAL;
89 	}
90 
91 	dev_dbg(dp->dev, "success to get plug in status after force hpd\n");
92 
93 	return 0;
94 }
95 
analogix_dp_detect_sink_psr(struct analogix_dp_device * dp)96 static bool analogix_dp_detect_sink_psr(struct analogix_dp_device *dp)
97 {
98 	unsigned char psr_version;
99 	int ret;
100 
101 	ret = drm_dp_dpcd_readb(&dp->aux, DP_PSR_SUPPORT, &psr_version);
102 	if (ret != 1) {
103 		dev_err(dp->dev, "failed to get PSR version, disable it\n");
104 		return false;
105 	}
106 
107 	dev_dbg(dp->dev, "Panel PSR version : %x\n", psr_version);
108 	return psr_version & DP_PSR_IS_SUPPORTED;
109 }
110 
analogix_dp_enable_sink_psr(struct analogix_dp_device * dp)111 static int analogix_dp_enable_sink_psr(struct analogix_dp_device *dp)
112 {
113 	unsigned char psr_en;
114 	int ret;
115 
116 	/* Disable psr function */
117 	ret = drm_dp_dpcd_readb(&dp->aux, DP_PSR_EN_CFG, &psr_en);
118 	if (ret != 1) {
119 		dev_err(dp->dev, "failed to get psr config\n");
120 		goto end;
121 	}
122 
123 	psr_en &= ~DP_PSR_ENABLE;
124 	ret = drm_dp_dpcd_writeb(&dp->aux, DP_PSR_EN_CFG, psr_en);
125 	if (ret != 1) {
126 		dev_err(dp->dev, "failed to disable panel psr\n");
127 		goto end;
128 	}
129 
130 	/* Main-Link transmitter remains active during PSR active states */
131 	psr_en = DP_PSR_CRC_VERIFICATION;
132 	ret = drm_dp_dpcd_writeb(&dp->aux, DP_PSR_EN_CFG, psr_en);
133 	if (ret != 1) {
134 		dev_err(dp->dev, "failed to set panel psr\n");
135 		goto end;
136 	}
137 
138 	/* Enable psr function */
139 	psr_en = DP_PSR_ENABLE | DP_PSR_CRC_VERIFICATION;
140 	ret = drm_dp_dpcd_writeb(&dp->aux, DP_PSR_EN_CFG, psr_en);
141 	if (ret != 1) {
142 		dev_err(dp->dev, "failed to set panel psr\n");
143 		goto end;
144 	}
145 
146 	analogix_dp_enable_psr_crc(dp);
147 
148 	dp->psr_supported = true;
149 
150 	return 0;
151 end:
152 	dev_err(dp->dev, "enable psr fail, force to disable psr\n");
153 
154 	return ret;
155 }
156 
157 static int
analogix_dp_enable_rx_to_enhanced_mode(struct analogix_dp_device * dp,bool enable)158 analogix_dp_enable_rx_to_enhanced_mode(struct analogix_dp_device *dp,
159 				       bool enable)
160 {
161 	u8 data;
162 	int ret;
163 
164 	ret = drm_dp_dpcd_readb(&dp->aux, DP_LANE_COUNT_SET, &data);
165 	if (ret != 1)
166 		return ret;
167 
168 	if (enable)
169 		ret = drm_dp_dpcd_writeb(&dp->aux, DP_LANE_COUNT_SET,
170 					 DP_LANE_COUNT_ENHANCED_FRAME_EN |
171 					 DPCD_LANE_COUNT_SET(data));
172 	else
173 		ret = drm_dp_dpcd_writeb(&dp->aux, DP_LANE_COUNT_SET,
174 					 DPCD_LANE_COUNT_SET(data));
175 
176 	return ret < 0 ? ret : 0;
177 }
178 
analogix_dp_is_enhanced_mode_available(struct analogix_dp_device * dp,u8 * enhanced_mode_support)179 static int analogix_dp_is_enhanced_mode_available(struct analogix_dp_device *dp,
180 						  u8 *enhanced_mode_support)
181 {
182 	u8 data;
183 	int ret;
184 
185 	ret = drm_dp_dpcd_readb(&dp->aux, DP_MAX_LANE_COUNT, &data);
186 	if (ret != 1) {
187 		*enhanced_mode_support = 0;
188 		return ret;
189 	}
190 
191 	*enhanced_mode_support = DPCD_ENHANCED_FRAME_CAP(data);
192 
193 	return 0;
194 }
195 
analogix_dp_set_enhanced_mode(struct analogix_dp_device * dp)196 static int analogix_dp_set_enhanced_mode(struct analogix_dp_device *dp)
197 {
198 	u8 data;
199 	int ret;
200 
201 	ret = analogix_dp_is_enhanced_mode_available(dp, &data);
202 	if (ret < 0)
203 		return ret;
204 
205 	ret = analogix_dp_enable_rx_to_enhanced_mode(dp, data);
206 	if (ret < 0)
207 		return ret;
208 
209 	analogix_dp_enable_enhanced_mode(dp, data);
210 
211 	return 0;
212 }
213 
analogix_dp_training_pattern_dis(struct analogix_dp_device * dp)214 static int analogix_dp_training_pattern_dis(struct analogix_dp_device *dp)
215 {
216 	int ret;
217 
218 	analogix_dp_set_training_pattern(dp, DP_NONE);
219 
220 	ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
221 				 DP_TRAINING_PATTERN_DISABLE);
222 
223 	return ret < 0 ? ret : 0;
224 }
225 
analogix_dp_link_start(struct analogix_dp_device * dp)226 static int analogix_dp_link_start(struct analogix_dp_device *dp)
227 {
228 	u8 buf[4];
229 	int lane, lane_count, retval;
230 
231 	lane_count = dp->link_train.lane_count;
232 
233 	dp->link_train.lt_state = CLOCK_RECOVERY;
234 	dp->link_train.eq_loop = 0;
235 
236 	for (lane = 0; lane < lane_count; lane++)
237 		dp->link_train.cr_loop[lane] = 0;
238 
239 	/* Set link rate and count as you want to establish*/
240 	analogix_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
241 	retval = analogix_dp_wait_pll_locked(dp);
242 	if (retval) {
243 		DRM_DEV_ERROR(dp->dev, "Wait for pll lock failed %d\n", retval);
244 		return retval;
245 	}
246 	/*
247 	 * MACRO_RST must be applied after the PLL_LOCK to avoid
248 	 * the DP inter pair skew issue for at least 10 us
249 	 */
250 	analogix_dp_reset_macro(dp);
251 	analogix_dp_set_lane_count(dp, dp->link_train.lane_count);
252 
253 	/* Setup RX configuration */
254 	buf[0] = dp->link_train.link_rate;
255 	buf[1] = dp->link_train.lane_count;
256 	retval = drm_dp_dpcd_write(&dp->aux, DP_LINK_BW_SET, buf, 2);
257 	if (retval < 0)
258 		return retval;
259 	/* set enhanced mode if available */
260 	retval = analogix_dp_set_enhanced_mode(dp);
261 	if (retval < 0) {
262 		dev_err(dp->dev, "failed to set enhance mode\n");
263 		return retval;
264 	}
265 
266 	/* Set TX voltage-swing and pre-emphasis to minimum */
267 	for (lane = 0; lane < lane_count; lane++)
268 		dp->link_train.training_lane[lane] =
269 					DP_TRAIN_VOLTAGE_SWING_LEVEL_0 |
270 					DP_TRAIN_PRE_EMPH_LEVEL_0;
271 	analogix_dp_set_lane_link_training(dp);
272 
273 	/* Set training pattern 1 */
274 	analogix_dp_set_training_pattern(dp, TRAINING_PTN1);
275 
276 	/* Set RX training pattern */
277 	retval = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
278 				    DP_LINK_SCRAMBLING_DISABLE |
279 					DP_TRAINING_PATTERN_1);
280 	if (retval < 0)
281 		return retval;
282 
283 	for (lane = 0; lane < lane_count; lane++)
284 		buf[lane] = DP_TRAIN_PRE_EMPH_LEVEL_0 |
285 			    DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
286 
287 	retval = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET, buf,
288 				   lane_count);
289 	if (retval < 0)
290 		return retval;
291 
292 	return 0;
293 }
294 
analogix_dp_get_lane_status(u8 link_status[2],int lane)295 static unsigned char analogix_dp_get_lane_status(u8 link_status[2], int lane)
296 {
297 	int shift = (lane & 1) * 4;
298 	u8 link_value = link_status[lane >> 1];
299 
300 	return (link_value >> shift) & 0xf;
301 }
302 
analogix_dp_clock_recovery_ok(u8 link_status[2],int lane_count)303 static int analogix_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
304 {
305 	int lane;
306 	u8 lane_status;
307 
308 	for (lane = 0; lane < lane_count; lane++) {
309 		lane_status = analogix_dp_get_lane_status(link_status, lane);
310 		if ((lane_status & DP_LANE_CR_DONE) == 0)
311 			return -EINVAL;
312 	}
313 	return 0;
314 }
315 
analogix_dp_channel_eq_ok(u8 link_status[2],u8 link_align,int lane_count)316 static int analogix_dp_channel_eq_ok(u8 link_status[2], u8 link_align,
317 				     int lane_count)
318 {
319 	int lane;
320 	u8 lane_status;
321 
322 	if ((link_align & DP_INTERLANE_ALIGN_DONE) == 0)
323 		return -EINVAL;
324 
325 	for (lane = 0; lane < lane_count; lane++) {
326 		lane_status = analogix_dp_get_lane_status(link_status, lane);
327 		lane_status &= DP_CHANNEL_EQ_BITS;
328 		if (lane_status != DP_CHANNEL_EQ_BITS)
329 			return -EINVAL;
330 	}
331 
332 	return 0;
333 }
334 
335 static unsigned char
analogix_dp_get_adjust_request_voltage(u8 adjust_request[2],int lane)336 analogix_dp_get_adjust_request_voltage(u8 adjust_request[2], int lane)
337 {
338 	int shift = (lane & 1) * 4;
339 	u8 link_value = adjust_request[lane >> 1];
340 
341 	return (link_value >> shift) & 0x3;
342 }
343 
analogix_dp_get_adjust_request_pre_emphasis(u8 adjust_request[2],int lane)344 static unsigned char analogix_dp_get_adjust_request_pre_emphasis(
345 					u8 adjust_request[2],
346 					int lane)
347 {
348 	int shift = (lane & 1) * 4;
349 	u8 link_value = adjust_request[lane >> 1];
350 
351 	return ((link_value >> shift) & 0xc) >> 2;
352 }
353 
analogix_dp_reduce_link_rate(struct analogix_dp_device * dp)354 static void analogix_dp_reduce_link_rate(struct analogix_dp_device *dp)
355 {
356 	analogix_dp_training_pattern_dis(dp);
357 	analogix_dp_set_enhanced_mode(dp);
358 
359 	dp->link_train.lt_state = FAILED;
360 }
361 
analogix_dp_get_adjust_training_lane(struct analogix_dp_device * dp,u8 adjust_request[2])362 static void analogix_dp_get_adjust_training_lane(struct analogix_dp_device *dp,
363 						 u8 adjust_request[2])
364 {
365 	int lane, lane_count;
366 	u8 voltage_swing, pre_emphasis, training_lane;
367 
368 	lane_count = dp->link_train.lane_count;
369 	for (lane = 0; lane < lane_count; lane++) {
370 		voltage_swing = analogix_dp_get_adjust_request_voltage(
371 						adjust_request, lane);
372 		pre_emphasis = analogix_dp_get_adjust_request_pre_emphasis(
373 						adjust_request, lane);
374 		training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
375 				DPCD_PRE_EMPHASIS_SET(pre_emphasis);
376 
377 		if (voltage_swing == VOLTAGE_LEVEL_3)
378 			training_lane |= DP_TRAIN_MAX_SWING_REACHED;
379 		if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
380 			training_lane |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
381 
382 		dp->link_train.training_lane[lane] = training_lane;
383 	}
384 }
385 
analogix_dp_process_clock_recovery(struct analogix_dp_device * dp)386 static int analogix_dp_process_clock_recovery(struct analogix_dp_device *dp)
387 {
388 	int lane, lane_count, retval;
389 	u8 voltage_swing, pre_emphasis, training_lane;
390 	u8 link_status[2], adjust_request[2];
391 
392 	usleep_range(100, 101);
393 
394 	lane_count = dp->link_train.lane_count;
395 
396 	retval = drm_dp_dpcd_read(&dp->aux, DP_LANE0_1_STATUS, link_status, 2);
397 	if (retval < 0)
398 		return retval;
399 
400 	if (analogix_dp_clock_recovery_ok(link_status, lane_count) == 0) {
401 		/* set training pattern 2 for EQ */
402 		analogix_dp_set_training_pattern(dp, TRAINING_PTN2);
403 
404 		retval = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
405 					    DP_LINK_SCRAMBLING_DISABLE |
406 						DP_TRAINING_PATTERN_2);
407 		if (retval < 0)
408 			return retval;
409 
410 		dev_dbg(dp->dev, "Link Training Clock Recovery success\n");
411 		dp->link_train.lt_state = EQUALIZER_TRAINING;
412 
413 		return 0;
414 	}
415 
416 	retval = drm_dp_dpcd_read(&dp->aux, DP_ADJUST_REQUEST_LANE0_1,
417 				  adjust_request, 2);
418 	if (retval < 0)
419 		return retval;
420 
421 	for (lane = 0; lane < lane_count; lane++) {
422 		training_lane = analogix_dp_get_lane_link_training(dp, lane);
423 		voltage_swing = analogix_dp_get_adjust_request_voltage(adjust_request, lane);
424 		pre_emphasis = analogix_dp_get_adjust_request_pre_emphasis(adjust_request, lane);
425 
426 		if (DPCD_VOLTAGE_SWING_GET(training_lane) == voltage_swing &&
427 		    DPCD_PRE_EMPHASIS_GET(training_lane) == pre_emphasis)
428 			dp->link_train.cr_loop[lane]++;
429 
430 		if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP ||
431 		    voltage_swing == VOLTAGE_LEVEL_3 ||
432 		    pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
433 			dev_err(dp->dev, "CR Max reached (%d,%d,%d)\n",
434 				dp->link_train.cr_loop[lane],
435 				voltage_swing, pre_emphasis);
436 			analogix_dp_reduce_link_rate(dp);
437 			return -EIO;
438 		}
439 	}
440 
441 	analogix_dp_get_adjust_training_lane(dp, adjust_request);
442 	analogix_dp_set_lane_link_training(dp);
443 
444 	retval = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET,
445 				   dp->link_train.training_lane, lane_count);
446 	if (retval < 0)
447 		return retval;
448 
449 	return 0;
450 }
451 
analogix_dp_process_equalizer_training(struct analogix_dp_device * dp)452 static int analogix_dp_process_equalizer_training(struct analogix_dp_device *dp)
453 {
454 	int lane_count, retval;
455 	u32 reg;
456 	u8 link_align, link_status[2], adjust_request[2];
457 
458 	usleep_range(400, 401);
459 
460 	lane_count = dp->link_train.lane_count;
461 
462 	retval = drm_dp_dpcd_read(&dp->aux, DP_LANE0_1_STATUS, link_status, 2);
463 	if (retval < 0)
464 		return retval;
465 
466 	if (analogix_dp_clock_recovery_ok(link_status, lane_count)) {
467 		analogix_dp_reduce_link_rate(dp);
468 		return -EIO;
469 	}
470 
471 	retval = drm_dp_dpcd_read(&dp->aux, DP_ADJUST_REQUEST_LANE0_1,
472 				  adjust_request, 2);
473 	if (retval < 0)
474 		return retval;
475 
476 	retval = drm_dp_dpcd_readb(&dp->aux, DP_LANE_ALIGN_STATUS_UPDATED,
477 				   &link_align);
478 	if (retval < 0)
479 		return retval;
480 
481 	analogix_dp_get_adjust_training_lane(dp, adjust_request);
482 
483 	if (!analogix_dp_channel_eq_ok(link_status, link_align, lane_count)) {
484 		/* traing pattern Set to Normal */
485 		retval = analogix_dp_training_pattern_dis(dp);
486 		if (retval < 0)
487 			return retval;
488 
489 		dev_dbg(dp->dev, "Link Training success!\n");
490 		analogix_dp_get_link_bandwidth(dp, &reg);
491 		dp->link_train.link_rate = reg;
492 		dev_dbg(dp->dev, "final bandwidth = %.2x\n",
493 			dp->link_train.link_rate);
494 
495 		analogix_dp_get_lane_count(dp, &reg);
496 		dp->link_train.lane_count = reg;
497 		dev_dbg(dp->dev, "final lane count = %.2x\n",
498 			dp->link_train.lane_count);
499 
500 		dp->link_train.lt_state = FINISHED;
501 
502 		return 0;
503 	}
504 
505 	/* not all locked */
506 	dp->link_train.eq_loop++;
507 
508 	if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
509 		dev_err(dp->dev, "EQ Max loop\n");
510 		analogix_dp_reduce_link_rate(dp);
511 		return -EIO;
512 	}
513 
514 	analogix_dp_set_lane_link_training(dp);
515 
516 	retval = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET,
517 				   dp->link_train.training_lane, lane_count);
518 	if (retval < 0)
519 		return retval;
520 
521 	return 0;
522 }
523 
analogix_dp_get_max_rx_bandwidth(struct analogix_dp_device * dp,u8 * bandwidth)524 static void analogix_dp_get_max_rx_bandwidth(struct analogix_dp_device *dp,
525 					     u8 *bandwidth)
526 {
527 	u8 data;
528 
529 	/*
530 	 * For DP rev.1.1, Maximum link rate of Main Link lanes
531 	 * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
532 	 * For DP rev.1.2, Maximum link rate of Main Link lanes
533 	 * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps, 0x14 = 5.4Gbps
534 	 */
535 	drm_dp_dpcd_readb(&dp->aux, DP_MAX_LINK_RATE, &data);
536 	*bandwidth = data;
537 }
538 
analogix_dp_get_max_rx_lane_count(struct analogix_dp_device * dp,u8 * lane_count)539 static void analogix_dp_get_max_rx_lane_count(struct analogix_dp_device *dp,
540 					      u8 *lane_count)
541 {
542 	u8 data;
543 
544 	/*
545 	 * For DP rev.1.1, Maximum number of Main Link lanes
546 	 * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
547 	 */
548 	drm_dp_dpcd_readb(&dp->aux, DP_MAX_LANE_COUNT, &data);
549 	*lane_count = DPCD_MAX_LANE_COUNT(data);
550 }
551 
analogix_dp_full_link_train(struct analogix_dp_device * dp,u32 max_lanes,u32 max_rate)552 static int analogix_dp_full_link_train(struct analogix_dp_device *dp,
553 				       u32 max_lanes, u32 max_rate)
554 {
555 	int retval = 0;
556 	bool training_finished = false;
557 
558 	/* Initialize by reading RX's DPCD */
559 	analogix_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
560 	analogix_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
561 
562 	if ((dp->link_train.link_rate != DP_LINK_BW_1_62) &&
563 	    (dp->link_train.link_rate != DP_LINK_BW_2_7) &&
564 	    (dp->link_train.link_rate != DP_LINK_BW_5_4)) {
565 		dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
566 			dp->link_train.link_rate);
567 		dp->link_train.link_rate = DP_LINK_BW_1_62;
568 	}
569 
570 	if (dp->link_train.lane_count == 0) {
571 		dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
572 			dp->link_train.lane_count);
573 		dp->link_train.lane_count = (u8)LANE_COUNT1;
574 	}
575 
576 	/* Setup TX lane count & rate */
577 	if (dp->link_train.lane_count > max_lanes)
578 		dp->link_train.lane_count = max_lanes;
579 	if (dp->link_train.link_rate > max_rate)
580 		dp->link_train.link_rate = max_rate;
581 
582 	/* All DP analog module power up */
583 	analogix_dp_set_analog_power_down(dp, POWER_ALL, 0);
584 
585 	dp->link_train.lt_state = START;
586 
587 	/* Process here */
588 	while (!retval && !training_finished) {
589 		switch (dp->link_train.lt_state) {
590 		case START:
591 			retval = analogix_dp_link_start(dp);
592 			if (retval)
593 				dev_err(dp->dev, "LT link start failed!\n");
594 			break;
595 		case CLOCK_RECOVERY:
596 			retval = analogix_dp_process_clock_recovery(dp);
597 			if (retval)
598 				dev_err(dp->dev, "LT CR failed!\n");
599 			break;
600 		case EQUALIZER_TRAINING:
601 			retval = analogix_dp_process_equalizer_training(dp);
602 			if (retval)
603 				dev_err(dp->dev, "LT EQ failed!\n");
604 			break;
605 		case FINISHED:
606 			training_finished = 1;
607 			break;
608 		case FAILED:
609 			return -EREMOTEIO;
610 		}
611 	}
612 	if (retval)
613 		dev_err(dp->dev, "eDP link training failed (%d)\n", retval);
614 
615 	return retval;
616 }
617 
analogix_dp_fast_link_train(struct analogix_dp_device * dp)618 static int analogix_dp_fast_link_train(struct analogix_dp_device *dp)
619 {
620 	int ret;
621 	u8 link_align, link_status[2];
622 
623 	analogix_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
624 	ret = analogix_dp_wait_pll_locked(dp);
625 	if (ret) {
626 		DRM_DEV_ERROR(dp->dev, "Wait for pll lock failed %d\n", ret);
627 		return ret;
628 	}
629 
630 	/*
631 	 * MACRO_RST must be applied after the PLL_LOCK to avoid
632 	 * the DP inter pair skew issue for at least 10 us
633 	 */
634 	analogix_dp_reset_macro(dp);
635 	analogix_dp_set_lane_count(dp, dp->link_train.lane_count);
636 	analogix_dp_set_lane_link_training(dp);
637 
638 	/* source Set training pattern 1 */
639 	analogix_dp_set_training_pattern(dp, TRAINING_PTN1);
640 	/* From DP spec, pattern must be on-screen for a minimum 500us */
641 	usleep_range(500, 600);
642 
643 	analogix_dp_set_training_pattern(dp, TRAINING_PTN2);
644 	/* From DP spec, pattern must be on-screen for a minimum 500us */
645 	usleep_range(500, 600);
646 
647 	/* TODO: enhanced_mode?*/
648 	analogix_dp_set_training_pattern(dp, DP_NONE);
649 
650 	/*
651 	 * Useful for debugging issues with fast link training, disable for more
652 	 * speed
653 	 */
654 	if (verify_fast_training) {
655 		ret = drm_dp_dpcd_readb(&dp->aux, DP_LANE_ALIGN_STATUS_UPDATED,
656 					&link_align);
657 		if (ret < 0) {
658 			DRM_DEV_ERROR(dp->dev, "Read align status failed %d\n",
659 				      ret);
660 			return ret;
661 		}
662 
663 		ret = drm_dp_dpcd_read(&dp->aux, DP_LANE0_1_STATUS, link_status,
664 				       2);
665 		if (ret < 0) {
666 			DRM_DEV_ERROR(dp->dev, "Read link status failed %d\n",
667 				      ret);
668 			return ret;
669 		}
670 
671 		if (analogix_dp_clock_recovery_ok(link_status,
672 						  dp->link_train.lane_count)) {
673 			DRM_DEV_ERROR(dp->dev, "Clock recovery failed\n");
674 			analogix_dp_reduce_link_rate(dp);
675 			return -EIO;
676 		}
677 
678 		if (analogix_dp_channel_eq_ok(link_status, link_align,
679 					      dp->link_train.lane_count)) {
680 			DRM_DEV_ERROR(dp->dev, "Channel EQ failed\n");
681 			analogix_dp_reduce_link_rate(dp);
682 			return -EIO;
683 		}
684 	}
685 
686 	return 0;
687 }
688 
analogix_dp_train_link(struct analogix_dp_device * dp)689 static int analogix_dp_train_link(struct analogix_dp_device *dp)
690 {
691 	if (dp->fast_train_enable)
692 		return analogix_dp_fast_link_train(dp);
693 
694 	return analogix_dp_full_link_train(dp, dp->video_info.max_lane_count,
695 					   dp->video_info.max_link_rate);
696 }
697 
analogix_dp_config_video(struct analogix_dp_device * dp)698 static int analogix_dp_config_video(struct analogix_dp_device *dp)
699 {
700 	int timeout_loop = 0;
701 	int done_count = 0;
702 
703 	analogix_dp_config_video_slave_mode(dp);
704 
705 	analogix_dp_set_video_color_format(dp);
706 
707 	for (;;) {
708 		timeout_loop++;
709 		if (analogix_dp_is_slave_video_stream_clock_on(dp) == 0)
710 			break;
711 		if (timeout_loop > DP_TIMEOUT_LOOP_COUNT) {
712 			dev_err(dp->dev, "Timeout of slave video streamclk ok\n");
713 			return -ETIMEDOUT;
714 		}
715 		usleep_range(1000, 1001);
716 	}
717 
718 	/* Set to use the register calculated M/N video */
719 	analogix_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
720 
721 	/* For video bist, Video timing must be generated by register */
722 	analogix_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
723 
724 	/* Disable video mute */
725 	analogix_dp_enable_video_mute(dp, 0);
726 
727 	/* Configure video slave mode */
728 	analogix_dp_enable_video_master(dp, 0);
729 
730 	/* Enable video */
731 	analogix_dp_start_video(dp);
732 
733 	timeout_loop = 0;
734 
735 	for (;;) {
736 		timeout_loop++;
737 		if (analogix_dp_is_video_stream_on(dp) == 0) {
738 			done_count++;
739 			if (done_count > 10)
740 				break;
741 		} else if (done_count) {
742 			done_count = 0;
743 		}
744 		if (timeout_loop > DP_TIMEOUT_LOOP_COUNT) {
745 			dev_warn(dp->dev,
746 				 "Ignoring timeout of video streamclk ok\n");
747 			break;
748 		}
749 
750 		usleep_range(1000, 1001);
751 	}
752 
753 	return 0;
754 }
755 
analogix_dp_enable_scramble(struct analogix_dp_device * dp,bool enable)756 static int analogix_dp_enable_scramble(struct analogix_dp_device *dp,
757 				       bool enable)
758 {
759 	u8 data;
760 	int ret;
761 
762 	if (enable) {
763 		analogix_dp_enable_scrambling(dp);
764 
765 		ret = drm_dp_dpcd_readb(&dp->aux, DP_TRAINING_PATTERN_SET,
766 					&data);
767 		if (ret != 1)
768 			return ret;
769 		ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
770 				   (u8)(data & ~DP_LINK_SCRAMBLING_DISABLE));
771 	} else {
772 		analogix_dp_disable_scrambling(dp);
773 
774 		ret = drm_dp_dpcd_readb(&dp->aux, DP_TRAINING_PATTERN_SET,
775 					&data);
776 		if (ret != 1)
777 			return ret;
778 		ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
779 				   (u8)(data | DP_LINK_SCRAMBLING_DISABLE));
780 	}
781 	return ret < 0 ? ret : 0;
782 }
783 
analogix_dp_hardirq(int irq,void * arg)784 static irqreturn_t analogix_dp_hardirq(int irq, void *arg)
785 {
786 	struct analogix_dp_device *dp = arg;
787 	irqreturn_t ret = IRQ_NONE;
788 	enum dp_irq_type irq_type;
789 
790 	irq_type = analogix_dp_get_irq_type(dp);
791 	if (irq_type != DP_IRQ_TYPE_UNKNOWN) {
792 		analogix_dp_mute_hpd_interrupt(dp);
793 		ret = IRQ_WAKE_THREAD;
794 	}
795 
796 	return ret;
797 }
798 
analogix_dp_irq_thread(int irq,void * arg)799 static irqreturn_t analogix_dp_irq_thread(int irq, void *arg)
800 {
801 	struct analogix_dp_device *dp = arg;
802 	enum dp_irq_type irq_type;
803 
804 	irq_type = analogix_dp_get_irq_type(dp);
805 	if (irq_type & DP_IRQ_TYPE_HP_CABLE_IN ||
806 	    irq_type & DP_IRQ_TYPE_HP_CABLE_OUT) {
807 		dev_dbg(dp->dev, "Detected cable status changed!\n");
808 		if (dp->drm_dev)
809 			drm_helper_hpd_irq_event(dp->drm_dev);
810 	}
811 
812 	if (irq_type != DP_IRQ_TYPE_UNKNOWN) {
813 		analogix_dp_clear_hotplug_interrupts(dp);
814 		analogix_dp_unmute_hpd_interrupt(dp);
815 	}
816 
817 	return IRQ_HANDLED;
818 }
819 
analogix_dp_fast_link_train_detection(struct analogix_dp_device * dp)820 static int analogix_dp_fast_link_train_detection(struct analogix_dp_device *dp)
821 {
822 	int ret;
823 	u8 spread;
824 
825 	ret = drm_dp_dpcd_readb(&dp->aux, DP_MAX_DOWNSPREAD, &spread);
826 	if (ret != 1) {
827 		dev_err(dp->dev, "failed to read downspread %d\n", ret);
828 		return ret;
829 	}
830 	dp->fast_train_enable = !!(spread & DP_NO_AUX_HANDSHAKE_LINK_TRAINING);
831 	dev_dbg(dp->dev, "fast link training %s\n",
832 		dp->fast_train_enable ? "supported" : "unsupported");
833 	return 0;
834 }
835 
analogix_dp_commit(struct analogix_dp_device * dp)836 static int analogix_dp_commit(struct analogix_dp_device *dp)
837 {
838 	int ret;
839 
840 	/* Keep the panel disabled while we configure video */
841 	if (dp->plat_data->panel) {
842 		if (drm_panel_disable(dp->plat_data->panel))
843 			DRM_ERROR("failed to disable the panel\n");
844 	}
845 
846 	ret = analogix_dp_train_link(dp);
847 	if (ret) {
848 		dev_err(dp->dev, "unable to do link train, ret=%d\n", ret);
849 		return ret;
850 	}
851 
852 	ret = analogix_dp_enable_scramble(dp, 1);
853 	if (ret < 0) {
854 		dev_err(dp->dev, "can not enable scramble\n");
855 		return ret;
856 	}
857 
858 	analogix_dp_init_video(dp);
859 	ret = analogix_dp_config_video(dp);
860 	if (ret) {
861 		dev_err(dp->dev, "unable to config video\n");
862 		return ret;
863 	}
864 
865 	/* Safe to enable the panel now */
866 	if (dp->plat_data->panel) {
867 		ret = drm_panel_enable(dp->plat_data->panel);
868 		if (ret) {
869 			DRM_ERROR("failed to enable the panel\n");
870 			return ret;
871 		}
872 	}
873 
874 	/* Check whether panel supports fast training */
875 	ret = analogix_dp_fast_link_train_detection(dp);
876 	if (ret)
877 		return ret;
878 
879 	if (analogix_dp_detect_sink_psr(dp)) {
880 		ret = analogix_dp_enable_sink_psr(dp);
881 		if (ret)
882 			return ret;
883 	}
884 
885 	return ret;
886 }
887 
analogix_dp_enable_psr(struct analogix_dp_device * dp)888 static int analogix_dp_enable_psr(struct analogix_dp_device *dp)
889 {
890 	struct dp_sdp psr_vsc;
891 	int ret;
892 	u8 sink;
893 
894 	ret = drm_dp_dpcd_readb(&dp->aux, DP_PSR_STATUS, &sink);
895 	if (ret != 1)
896 		DRM_DEV_ERROR(dp->dev, "Failed to read psr status %d\n", ret);
897 	else if (sink == DP_PSR_SINK_ACTIVE_RFB)
898 		return 0;
899 
900 	/* Prepare VSC packet as per EDP 1.4 spec, Table 6.9 */
901 	memset(&psr_vsc, 0, sizeof(psr_vsc));
902 	psr_vsc.sdp_header.HB0 = 0;
903 	psr_vsc.sdp_header.HB1 = 0x7;
904 	psr_vsc.sdp_header.HB2 = 0x2;
905 	psr_vsc.sdp_header.HB3 = 0x8;
906 	psr_vsc.db[0] = 0;
907 	psr_vsc.db[1] = EDP_VSC_PSR_STATE_ACTIVE | EDP_VSC_PSR_CRC_VALUES_VALID;
908 
909 	ret = analogix_dp_send_psr_spd(dp, &psr_vsc, true);
910 	if (!ret)
911 		analogix_dp_set_analog_power_down(dp, POWER_ALL, true);
912 
913 	return ret;
914 }
915 
analogix_dp_disable_psr(struct analogix_dp_device * dp)916 static int analogix_dp_disable_psr(struct analogix_dp_device *dp)
917 {
918 	struct dp_sdp psr_vsc;
919 	int ret;
920 	u8 sink;
921 
922 	analogix_dp_set_analog_power_down(dp, POWER_ALL, false);
923 
924 	ret = drm_dp_dpcd_writeb(&dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
925 	if (ret != 1) {
926 		DRM_DEV_ERROR(dp->dev, "Failed to set DP Power0 %d\n", ret);
927 		return ret;
928 	}
929 
930 	ret = drm_dp_dpcd_readb(&dp->aux, DP_PSR_STATUS, &sink);
931 	if (ret != 1) {
932 		DRM_DEV_ERROR(dp->dev, "Failed to read psr status %d\n", ret);
933 		return ret;
934 	} else if (sink == DP_PSR_SINK_INACTIVE) {
935 		DRM_DEV_ERROR(dp->dev, "sink inactive, skip disable psr");
936 		return 0;
937 	}
938 
939 	ret = analogix_dp_train_link(dp);
940 	if (ret) {
941 		DRM_DEV_ERROR(dp->dev, "Failed to train the link %d\n", ret);
942 		return ret;
943 	}
944 
945 	/* Prepare VSC packet as per EDP 1.4 spec, Table 6.9 */
946 	memset(&psr_vsc, 0, sizeof(psr_vsc));
947 	psr_vsc.sdp_header.HB0 = 0;
948 	psr_vsc.sdp_header.HB1 = 0x7;
949 	psr_vsc.sdp_header.HB2 = 0x2;
950 	psr_vsc.sdp_header.HB3 = 0x8;
951 
952 	psr_vsc.db[0] = 0;
953 	psr_vsc.db[1] = 0;
954 
955 	return analogix_dp_send_psr_spd(dp, &psr_vsc, true);
956 }
957 
958 /*
959  * This function is a bit of a catch-all for panel preparation, hopefully
960  * simplifying the logic of functions that need to prepare/unprepare the panel
961  * below.
962  *
963  * If @prepare is true, this function will prepare the panel. Conversely, if it
964  * is false, the panel will be unprepared.
965  *
966  * If @is_modeset_prepare is true, the function will disregard the current state
967  * of the panel and either prepare/unprepare the panel based on @prepare. Once
968  * it finishes, it will update dp->panel_is_modeset to reflect the current state
969  * of the panel.
970  */
analogix_dp_prepare_panel(struct analogix_dp_device * dp,bool prepare,bool is_modeset_prepare)971 static int analogix_dp_prepare_panel(struct analogix_dp_device *dp,
972 				     bool prepare, bool is_modeset_prepare)
973 {
974 	int ret = 0;
975 
976 	if (!dp->plat_data->panel)
977 		return 0;
978 
979 	mutex_lock(&dp->panel_lock);
980 
981 	/*
982 	 * Exit early if this is a temporary prepare/unprepare and we're already
983 	 * modeset (since we neither want to prepare twice or unprepare early).
984 	 */
985 	if (dp->panel_is_modeset && !is_modeset_prepare)
986 		goto out;
987 
988 	if (prepare)
989 		ret = drm_panel_prepare(dp->plat_data->panel);
990 	else
991 		ret = drm_panel_unprepare(dp->plat_data->panel);
992 
993 	if (ret)
994 		goto out;
995 
996 	if (is_modeset_prepare)
997 		dp->panel_is_modeset = prepare;
998 
999 out:
1000 	mutex_unlock(&dp->panel_lock);
1001 	return ret;
1002 }
1003 
analogix_dp_get_modes(struct drm_connector * connector)1004 static int analogix_dp_get_modes(struct drm_connector *connector)
1005 {
1006 	struct analogix_dp_device *dp = to_dp(connector);
1007 	const struct drm_edid *drm_edid;
1008 	int ret, num_modes = 0;
1009 
1010 	if (dp->plat_data->panel) {
1011 		num_modes += drm_panel_get_modes(dp->plat_data->panel, connector);
1012 	} else {
1013 		ret = analogix_dp_prepare_panel(dp, true, false);
1014 		if (ret) {
1015 			DRM_ERROR("Failed to prepare panel (%d)\n", ret);
1016 			return 0;
1017 		}
1018 
1019 		drm_edid = drm_edid_read_ddc(connector, &dp->aux.ddc);
1020 
1021 		drm_edid_connector_update(&dp->connector, drm_edid);
1022 
1023 		if (drm_edid) {
1024 			num_modes += drm_edid_connector_add_modes(&dp->connector);
1025 			drm_edid_free(drm_edid);
1026 		}
1027 
1028 		ret = analogix_dp_prepare_panel(dp, false, false);
1029 		if (ret)
1030 			DRM_ERROR("Failed to unprepare panel (%d)\n", ret);
1031 	}
1032 
1033 	if (dp->plat_data->get_modes)
1034 		num_modes += dp->plat_data->get_modes(dp->plat_data, connector);
1035 
1036 	return num_modes;
1037 }
1038 
1039 static struct drm_encoder *
analogix_dp_best_encoder(struct drm_connector * connector)1040 analogix_dp_best_encoder(struct drm_connector *connector)
1041 {
1042 	struct analogix_dp_device *dp = to_dp(connector);
1043 
1044 	return dp->encoder;
1045 }
1046 
1047 
analogix_dp_atomic_check(struct drm_connector * connector,struct drm_atomic_state * state)1048 static int analogix_dp_atomic_check(struct drm_connector *connector,
1049 				    struct drm_atomic_state *state)
1050 {
1051 	struct analogix_dp_device *dp = to_dp(connector);
1052 	struct drm_connector_state *conn_state;
1053 	struct drm_crtc_state *crtc_state;
1054 
1055 	conn_state = drm_atomic_get_new_connector_state(state, connector);
1056 	if (WARN_ON(!conn_state))
1057 		return -ENODEV;
1058 
1059 	conn_state->self_refresh_aware = true;
1060 
1061 	if (!conn_state->crtc)
1062 		return 0;
1063 
1064 	crtc_state = drm_atomic_get_new_crtc_state(state, conn_state->crtc);
1065 	if (!crtc_state)
1066 		return 0;
1067 
1068 	if (crtc_state->self_refresh_active && !dp->psr_supported)
1069 		return -EINVAL;
1070 
1071 	return 0;
1072 }
1073 
1074 static const struct drm_connector_helper_funcs analogix_dp_connector_helper_funcs = {
1075 	.get_modes = analogix_dp_get_modes,
1076 	.best_encoder = analogix_dp_best_encoder,
1077 	.atomic_check = analogix_dp_atomic_check,
1078 };
1079 
1080 static enum drm_connector_status
analogix_dp_detect(struct drm_connector * connector,bool force)1081 analogix_dp_detect(struct drm_connector *connector, bool force)
1082 {
1083 	struct analogix_dp_device *dp = to_dp(connector);
1084 	enum drm_connector_status status = connector_status_disconnected;
1085 	int ret;
1086 
1087 	if (dp->plat_data->panel)
1088 		return connector_status_connected;
1089 
1090 	ret = analogix_dp_prepare_panel(dp, true, false);
1091 	if (ret) {
1092 		DRM_ERROR("Failed to prepare panel (%d)\n", ret);
1093 		return connector_status_disconnected;
1094 	}
1095 
1096 	if (!analogix_dp_detect_hpd(dp))
1097 		status = connector_status_connected;
1098 
1099 	ret = analogix_dp_prepare_panel(dp, false, false);
1100 	if (ret)
1101 		DRM_ERROR("Failed to unprepare panel (%d)\n", ret);
1102 
1103 	return status;
1104 }
1105 
1106 static const struct drm_connector_funcs analogix_dp_connector_funcs = {
1107 	.fill_modes = drm_helper_probe_single_connector_modes,
1108 	.detect = analogix_dp_detect,
1109 	.destroy = drm_connector_cleanup,
1110 	.reset = drm_atomic_helper_connector_reset,
1111 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
1112 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
1113 };
1114 
analogix_dp_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)1115 static int analogix_dp_bridge_attach(struct drm_bridge *bridge,
1116 				     enum drm_bridge_attach_flags flags)
1117 {
1118 	struct analogix_dp_device *dp = bridge->driver_private;
1119 	struct drm_encoder *encoder = dp->encoder;
1120 	struct drm_connector *connector = NULL;
1121 	int ret = 0;
1122 
1123 	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
1124 		DRM_ERROR("Fix bridge driver to make connector optional!");
1125 		return -EINVAL;
1126 	}
1127 
1128 	if (!dp->plat_data->skip_connector) {
1129 		connector = &dp->connector;
1130 		connector->polled = DRM_CONNECTOR_POLL_HPD;
1131 
1132 		ret = drm_connector_init(dp->drm_dev, connector,
1133 					 &analogix_dp_connector_funcs,
1134 					 DRM_MODE_CONNECTOR_eDP);
1135 		if (ret) {
1136 			DRM_ERROR("Failed to initialize connector with drm\n");
1137 			return ret;
1138 		}
1139 
1140 		drm_connector_helper_add(connector,
1141 					 &analogix_dp_connector_helper_funcs);
1142 		drm_connector_attach_encoder(connector, encoder);
1143 	}
1144 
1145 	/*
1146 	 * NOTE: the connector registration is implemented in analogix
1147 	 * platform driver, that to say connector would be exist after
1148 	 * plat_data->attch return, that's why we record the connector
1149 	 * point after plat attached.
1150 	 */
1151 	if (dp->plat_data->attach) {
1152 		ret = dp->plat_data->attach(dp->plat_data, bridge, connector);
1153 		if (ret) {
1154 			DRM_ERROR("Failed at platform attach func\n");
1155 			return ret;
1156 		}
1157 	}
1158 
1159 	return 0;
1160 }
1161 
1162 static
analogix_dp_get_old_crtc(struct analogix_dp_device * dp,struct drm_atomic_state * state)1163 struct drm_crtc *analogix_dp_get_old_crtc(struct analogix_dp_device *dp,
1164 					  struct drm_atomic_state *state)
1165 {
1166 	struct drm_encoder *encoder = dp->encoder;
1167 	struct drm_connector *connector;
1168 	struct drm_connector_state *conn_state;
1169 
1170 	connector = drm_atomic_get_old_connector_for_encoder(state, encoder);
1171 	if (!connector)
1172 		return NULL;
1173 
1174 	conn_state = drm_atomic_get_old_connector_state(state, connector);
1175 	if (!conn_state)
1176 		return NULL;
1177 
1178 	return conn_state->crtc;
1179 }
1180 
1181 static
analogix_dp_get_new_crtc(struct analogix_dp_device * dp,struct drm_atomic_state * state)1182 struct drm_crtc *analogix_dp_get_new_crtc(struct analogix_dp_device *dp,
1183 					  struct drm_atomic_state *state)
1184 {
1185 	struct drm_encoder *encoder = dp->encoder;
1186 	struct drm_connector *connector;
1187 	struct drm_connector_state *conn_state;
1188 
1189 	connector = drm_atomic_get_new_connector_for_encoder(state, encoder);
1190 	if (!connector)
1191 		return NULL;
1192 
1193 	conn_state = drm_atomic_get_new_connector_state(state, connector);
1194 	if (!conn_state)
1195 		return NULL;
1196 
1197 	return conn_state->crtc;
1198 }
1199 
1200 static void
analogix_dp_bridge_atomic_pre_enable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)1201 analogix_dp_bridge_atomic_pre_enable(struct drm_bridge *bridge,
1202 				     struct drm_bridge_state *old_bridge_state)
1203 {
1204 	struct drm_atomic_state *old_state = old_bridge_state->base.state;
1205 	struct analogix_dp_device *dp = bridge->driver_private;
1206 	struct drm_crtc *crtc;
1207 	struct drm_crtc_state *old_crtc_state;
1208 	int ret;
1209 
1210 	crtc = analogix_dp_get_new_crtc(dp, old_state);
1211 	if (!crtc)
1212 		return;
1213 
1214 	old_crtc_state = drm_atomic_get_old_crtc_state(old_state, crtc);
1215 	/* Don't touch the panel if we're coming back from PSR */
1216 	if (old_crtc_state && old_crtc_state->self_refresh_active)
1217 		return;
1218 
1219 	ret = analogix_dp_prepare_panel(dp, true, true);
1220 	if (ret)
1221 		DRM_ERROR("failed to setup the panel ret = %d\n", ret);
1222 }
1223 
analogix_dp_set_bridge(struct analogix_dp_device * dp)1224 static int analogix_dp_set_bridge(struct analogix_dp_device *dp)
1225 {
1226 	int ret;
1227 
1228 	pm_runtime_get_sync(dp->dev);
1229 
1230 	ret = analogix_dp_init_analog_func(dp);
1231 	if (ret)
1232 		return ret;
1233 
1234 	/*
1235 	 * According to DP spec v1.3 chap 3.5.1.2 Link Training,
1236 	 * We should first make sure the HPD signal is asserted high by device
1237 	 * when we want to establish a link with it.
1238 	 */
1239 	ret = analogix_dp_detect_hpd(dp);
1240 	if (ret) {
1241 		DRM_ERROR("failed to get hpd single ret = %d\n", ret);
1242 		goto out_dp_init;
1243 	}
1244 
1245 	ret = analogix_dp_commit(dp);
1246 	if (ret) {
1247 		DRM_ERROR("dp commit error, ret = %d\n", ret);
1248 		goto out_dp_init;
1249 	}
1250 
1251 	enable_irq(dp->irq);
1252 	return 0;
1253 
1254 out_dp_init:
1255 	pm_runtime_put_sync(dp->dev);
1256 
1257 	return ret;
1258 }
1259 
1260 static void
analogix_dp_bridge_atomic_enable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)1261 analogix_dp_bridge_atomic_enable(struct drm_bridge *bridge,
1262 				 struct drm_bridge_state *old_bridge_state)
1263 {
1264 	struct drm_atomic_state *old_state = old_bridge_state->base.state;
1265 	struct analogix_dp_device *dp = bridge->driver_private;
1266 	struct drm_crtc *crtc;
1267 	struct drm_crtc_state *old_crtc_state;
1268 	int timeout_loop = 0;
1269 	int ret;
1270 
1271 	crtc = analogix_dp_get_new_crtc(dp, old_state);
1272 	if (!crtc)
1273 		return;
1274 
1275 	old_crtc_state = drm_atomic_get_old_crtc_state(old_state, crtc);
1276 	/* Not a full enable, just disable PSR and continue */
1277 	if (old_crtc_state && old_crtc_state->self_refresh_active) {
1278 		ret = analogix_dp_disable_psr(dp);
1279 		if (ret)
1280 			DRM_ERROR("Failed to disable psr %d\n", ret);
1281 		return;
1282 	}
1283 
1284 	if (dp->dpms_mode == DRM_MODE_DPMS_ON)
1285 		return;
1286 
1287 	while (timeout_loop < MAX_PLL_LOCK_LOOP) {
1288 		if (analogix_dp_set_bridge(dp) == 0) {
1289 			dp->dpms_mode = DRM_MODE_DPMS_ON;
1290 			return;
1291 		}
1292 		dev_err(dp->dev, "failed to set bridge, retry: %d\n",
1293 			timeout_loop);
1294 		timeout_loop++;
1295 		usleep_range(10, 11);
1296 	}
1297 	dev_err(dp->dev, "too many times retry set bridge, give it up\n");
1298 }
1299 
analogix_dp_bridge_disable(struct drm_bridge * bridge)1300 static void analogix_dp_bridge_disable(struct drm_bridge *bridge)
1301 {
1302 	struct analogix_dp_device *dp = bridge->driver_private;
1303 	int ret;
1304 
1305 	if (dp->dpms_mode != DRM_MODE_DPMS_ON)
1306 		return;
1307 
1308 	if (dp->plat_data->panel) {
1309 		if (drm_panel_disable(dp->plat_data->panel)) {
1310 			DRM_ERROR("failed to disable the panel\n");
1311 			return;
1312 		}
1313 	}
1314 
1315 	disable_irq(dp->irq);
1316 
1317 	analogix_dp_set_analog_power_down(dp, POWER_ALL, 1);
1318 
1319 	pm_runtime_put_sync(dp->dev);
1320 
1321 	ret = analogix_dp_prepare_panel(dp, false, true);
1322 	if (ret)
1323 		DRM_ERROR("failed to setup the panel ret = %d\n", ret);
1324 
1325 	dp->fast_train_enable = false;
1326 	dp->psr_supported = false;
1327 	dp->dpms_mode = DRM_MODE_DPMS_OFF;
1328 }
1329 
1330 static void
analogix_dp_bridge_atomic_disable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)1331 analogix_dp_bridge_atomic_disable(struct drm_bridge *bridge,
1332 				  struct drm_bridge_state *old_bridge_state)
1333 {
1334 	struct drm_atomic_state *old_state = old_bridge_state->base.state;
1335 	struct analogix_dp_device *dp = bridge->driver_private;
1336 	struct drm_crtc *old_crtc, *new_crtc;
1337 	struct drm_crtc_state *old_crtc_state = NULL;
1338 	struct drm_crtc_state *new_crtc_state = NULL;
1339 	int ret;
1340 
1341 	new_crtc = analogix_dp_get_new_crtc(dp, old_state);
1342 	if (!new_crtc)
1343 		goto out;
1344 
1345 	new_crtc_state = drm_atomic_get_new_crtc_state(old_state, new_crtc);
1346 	if (!new_crtc_state)
1347 		goto out;
1348 
1349 	/* Don't do a full disable on PSR transitions */
1350 	if (new_crtc_state->self_refresh_active)
1351 		return;
1352 
1353 out:
1354 	old_crtc = analogix_dp_get_old_crtc(dp, old_state);
1355 	if (old_crtc) {
1356 		old_crtc_state = drm_atomic_get_old_crtc_state(old_state,
1357 							       old_crtc);
1358 
1359 		/* When moving from PSR to fully disabled, exit PSR first. */
1360 		if (old_crtc_state && old_crtc_state->self_refresh_active) {
1361 			ret = analogix_dp_disable_psr(dp);
1362 			if (ret)
1363 				DRM_ERROR("Failed to disable psr (%d)\n", ret);
1364 		}
1365 	}
1366 
1367 	analogix_dp_bridge_disable(bridge);
1368 }
1369 
1370 static void
analogix_dp_bridge_atomic_post_disable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)1371 analogix_dp_bridge_atomic_post_disable(struct drm_bridge *bridge,
1372 				struct drm_bridge_state *old_bridge_state)
1373 {
1374 	struct drm_atomic_state *old_state = old_bridge_state->base.state;
1375 	struct analogix_dp_device *dp = bridge->driver_private;
1376 	struct drm_crtc *crtc;
1377 	struct drm_crtc_state *new_crtc_state;
1378 	int ret;
1379 
1380 	crtc = analogix_dp_get_new_crtc(dp, old_state);
1381 	if (!crtc)
1382 		return;
1383 
1384 	new_crtc_state = drm_atomic_get_new_crtc_state(old_state, crtc);
1385 	if (!new_crtc_state || !new_crtc_state->self_refresh_active)
1386 		return;
1387 
1388 	ret = analogix_dp_enable_psr(dp);
1389 	if (ret)
1390 		DRM_ERROR("Failed to enable psr (%d)\n", ret);
1391 }
1392 
analogix_dp_bridge_mode_set(struct drm_bridge * bridge,const struct drm_display_mode * orig_mode,const struct drm_display_mode * mode)1393 static void analogix_dp_bridge_mode_set(struct drm_bridge *bridge,
1394 				const struct drm_display_mode *orig_mode,
1395 				const struct drm_display_mode *mode)
1396 {
1397 	struct analogix_dp_device *dp = bridge->driver_private;
1398 	struct drm_display_info *display_info = &dp->connector.display_info;
1399 	struct video_info *video = &dp->video_info;
1400 	struct device_node *dp_node = dp->dev->of_node;
1401 	int vic;
1402 
1403 	/* Input video interlaces & hsync pol & vsync pol */
1404 	video->interlaced = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
1405 	video->v_sync_polarity = !!(mode->flags & DRM_MODE_FLAG_NVSYNC);
1406 	video->h_sync_polarity = !!(mode->flags & DRM_MODE_FLAG_NHSYNC);
1407 
1408 	/* Input video dynamic_range & colorimetry */
1409 	vic = drm_match_cea_mode(mode);
1410 	if ((vic == 6) || (vic == 7) || (vic == 21) || (vic == 22) ||
1411 	    (vic == 2) || (vic == 3) || (vic == 17) || (vic == 18)) {
1412 		video->dynamic_range = CEA;
1413 		video->ycbcr_coeff = COLOR_YCBCR601;
1414 	} else if (vic) {
1415 		video->dynamic_range = CEA;
1416 		video->ycbcr_coeff = COLOR_YCBCR709;
1417 	} else {
1418 		video->dynamic_range = VESA;
1419 		video->ycbcr_coeff = COLOR_YCBCR709;
1420 	}
1421 
1422 	/* Input vide bpc and color_formats */
1423 	switch (display_info->bpc) {
1424 	case 12:
1425 		video->color_depth = COLOR_12;
1426 		break;
1427 	case 10:
1428 		video->color_depth = COLOR_10;
1429 		break;
1430 	case 8:
1431 		video->color_depth = COLOR_8;
1432 		break;
1433 	case 6:
1434 		video->color_depth = COLOR_6;
1435 		break;
1436 	default:
1437 		video->color_depth = COLOR_8;
1438 		break;
1439 	}
1440 	if (display_info->color_formats & DRM_COLOR_FORMAT_YCBCR444)
1441 		video->color_space = COLOR_YCBCR444;
1442 	else if (display_info->color_formats & DRM_COLOR_FORMAT_YCBCR422)
1443 		video->color_space = COLOR_YCBCR422;
1444 	else
1445 		video->color_space = COLOR_RGB;
1446 
1447 	/*
1448 	 * NOTE: those property parsing code is used for providing backward
1449 	 * compatibility for samsung platform.
1450 	 * Due to we used the "of_property_read_u32" interfaces, when this
1451 	 * property isn't present, the "video_info" can keep the original
1452 	 * values and wouldn't be modified.
1453 	 */
1454 	of_property_read_u32(dp_node, "samsung,color-space",
1455 			     &video->color_space);
1456 	of_property_read_u32(dp_node, "samsung,dynamic-range",
1457 			     &video->dynamic_range);
1458 	of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
1459 			     &video->ycbcr_coeff);
1460 	of_property_read_u32(dp_node, "samsung,color-depth",
1461 			     &video->color_depth);
1462 	if (of_property_read_bool(dp_node, "hsync-active-high"))
1463 		video->h_sync_polarity = true;
1464 	if (of_property_read_bool(dp_node, "vsync-active-high"))
1465 		video->v_sync_polarity = true;
1466 	if (of_property_read_bool(dp_node, "interlaced"))
1467 		video->interlaced = true;
1468 }
1469 
1470 static const struct drm_bridge_funcs analogix_dp_bridge_funcs = {
1471 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
1472 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
1473 	.atomic_reset = drm_atomic_helper_bridge_reset,
1474 	.atomic_pre_enable = analogix_dp_bridge_atomic_pre_enable,
1475 	.atomic_enable = analogix_dp_bridge_atomic_enable,
1476 	.atomic_disable = analogix_dp_bridge_atomic_disable,
1477 	.atomic_post_disable = analogix_dp_bridge_atomic_post_disable,
1478 	.mode_set = analogix_dp_bridge_mode_set,
1479 	.attach = analogix_dp_bridge_attach,
1480 };
1481 
analogix_dp_create_bridge(struct drm_device * drm_dev,struct analogix_dp_device * dp)1482 static int analogix_dp_create_bridge(struct drm_device *drm_dev,
1483 				     struct analogix_dp_device *dp)
1484 {
1485 	struct drm_bridge *bridge;
1486 
1487 	bridge = devm_kzalloc(drm_dev->dev, sizeof(*bridge), GFP_KERNEL);
1488 	if (!bridge) {
1489 		DRM_ERROR("failed to allocate for drm bridge\n");
1490 		return -ENOMEM;
1491 	}
1492 
1493 	dp->bridge = bridge;
1494 
1495 	bridge->driver_private = dp;
1496 	bridge->funcs = &analogix_dp_bridge_funcs;
1497 
1498 	return drm_bridge_attach(dp->encoder, bridge, NULL, 0);
1499 }
1500 
analogix_dp_dt_parse_pdata(struct analogix_dp_device * dp)1501 static int analogix_dp_dt_parse_pdata(struct analogix_dp_device *dp)
1502 {
1503 	struct device_node *dp_node = dp->dev->of_node;
1504 	struct video_info *video_info = &dp->video_info;
1505 
1506 	switch (dp->plat_data->dev_type) {
1507 	case RK3288_DP:
1508 	case RK3399_EDP:
1509 		/*
1510 		 * Like Rk3288 DisplayPort TRM indicate that "Main link
1511 		 * containing 4 physical lanes of 2.7/1.62 Gbps/lane".
1512 		 */
1513 		video_info->max_link_rate = 0x0A;
1514 		video_info->max_lane_count = 0x04;
1515 		break;
1516 	case EXYNOS_DP:
1517 		/*
1518 		 * NOTE: those property parseing code is used for
1519 		 * providing backward compatibility for samsung platform.
1520 		 */
1521 		of_property_read_u32(dp_node, "samsung,link-rate",
1522 				     &video_info->max_link_rate);
1523 		of_property_read_u32(dp_node, "samsung,lane-count",
1524 				     &video_info->max_lane_count);
1525 		break;
1526 	}
1527 
1528 	return 0;
1529 }
1530 
analogix_dpaux_transfer(struct drm_dp_aux * aux,struct drm_dp_aux_msg * msg)1531 static ssize_t analogix_dpaux_transfer(struct drm_dp_aux *aux,
1532 				       struct drm_dp_aux_msg *msg)
1533 {
1534 	struct analogix_dp_device *dp = to_dp(aux);
1535 	int ret;
1536 
1537 	pm_runtime_get_sync(dp->dev);
1538 
1539 	ret = analogix_dp_detect_hpd(dp);
1540 	if (ret)
1541 		goto out;
1542 
1543 	ret = analogix_dp_transfer(dp, msg);
1544 out:
1545 	pm_runtime_mark_last_busy(dp->dev);
1546 	pm_runtime_put_autosuspend(dp->dev);
1547 
1548 	return ret;
1549 }
1550 
1551 struct analogix_dp_device *
analogix_dp_probe(struct device * dev,struct analogix_dp_plat_data * plat_data)1552 analogix_dp_probe(struct device *dev, struct analogix_dp_plat_data *plat_data)
1553 {
1554 	struct platform_device *pdev = to_platform_device(dev);
1555 	struct analogix_dp_device *dp;
1556 	struct resource *res;
1557 	unsigned int irq_flags;
1558 	int ret;
1559 
1560 	if (!plat_data) {
1561 		dev_err(dev, "Invalided input plat_data\n");
1562 		return ERR_PTR(-EINVAL);
1563 	}
1564 
1565 	dp = devm_kzalloc(dev, sizeof(struct analogix_dp_device), GFP_KERNEL);
1566 	if (!dp)
1567 		return ERR_PTR(-ENOMEM);
1568 
1569 	dp->dev = &pdev->dev;
1570 	dp->dpms_mode = DRM_MODE_DPMS_OFF;
1571 
1572 	mutex_init(&dp->panel_lock);
1573 	dp->panel_is_modeset = false;
1574 
1575 	/*
1576 	 * platform dp driver need containor_of the plat_data to get
1577 	 * the driver private data, so we need to store the point of
1578 	 * plat_data, not the context of plat_data.
1579 	 */
1580 	dp->plat_data = plat_data;
1581 
1582 	ret = analogix_dp_dt_parse_pdata(dp);
1583 	if (ret)
1584 		return ERR_PTR(ret);
1585 
1586 	dp->phy = devm_phy_get(dp->dev, "dp");
1587 	if (IS_ERR(dp->phy)) {
1588 		dev_err(dp->dev, "no DP phy configured\n");
1589 		ret = PTR_ERR(dp->phy);
1590 		if (ret) {
1591 			/*
1592 			 * phy itself is not enabled, so we can move forward
1593 			 * assigning NULL to phy pointer.
1594 			 */
1595 			if (ret == -ENOSYS || ret == -ENODEV)
1596 				dp->phy = NULL;
1597 			else
1598 				return ERR_PTR(ret);
1599 		}
1600 	}
1601 
1602 	dp->clock = devm_clk_get(&pdev->dev, "dp");
1603 	if (IS_ERR(dp->clock)) {
1604 		dev_err(&pdev->dev, "failed to get clock\n");
1605 		return ERR_CAST(dp->clock);
1606 	}
1607 
1608 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1609 
1610 	dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
1611 	if (IS_ERR(dp->reg_base)) {
1612 		ret = PTR_ERR(dp->reg_base);
1613 		goto err_disable_clk;
1614 	}
1615 
1616 	dp->force_hpd = of_property_read_bool(dev->of_node, "force-hpd");
1617 
1618 	/* Try two different names */
1619 	dp->hpd_gpiod = devm_gpiod_get_optional(dev, "hpd", GPIOD_IN);
1620 	if (!dp->hpd_gpiod)
1621 		dp->hpd_gpiod = devm_gpiod_get_optional(dev, "samsung,hpd",
1622 							GPIOD_IN);
1623 	if (IS_ERR(dp->hpd_gpiod)) {
1624 		dev_err(dev, "error getting HDP GPIO: %ld\n",
1625 			PTR_ERR(dp->hpd_gpiod));
1626 		ret = PTR_ERR(dp->hpd_gpiod);
1627 		goto err_disable_clk;
1628 	}
1629 
1630 	if (dp->hpd_gpiod) {
1631 		/*
1632 		 * Set up the hotplug GPIO from the device tree as an interrupt.
1633 		 * Simply specifying a different interrupt in the device tree
1634 		 * doesn't work since we handle hotplug rather differently when
1635 		 * using a GPIO.  We also need the actual GPIO specifier so
1636 		 * that we can get the current state of the GPIO.
1637 		 */
1638 		dp->irq = gpiod_to_irq(dp->hpd_gpiod);
1639 		irq_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
1640 	} else {
1641 		dp->irq = platform_get_irq(pdev, 0);
1642 		irq_flags = 0;
1643 	}
1644 
1645 	if (dp->irq == -ENXIO) {
1646 		dev_err(&pdev->dev, "failed to get irq\n");
1647 		ret = -ENODEV;
1648 		goto err_disable_clk;
1649 	}
1650 
1651 	ret = devm_request_threaded_irq(&pdev->dev, dp->irq,
1652 					analogix_dp_hardirq,
1653 					analogix_dp_irq_thread,
1654 					irq_flags, "analogix-dp", dp);
1655 	if (ret) {
1656 		dev_err(&pdev->dev, "failed to request irq\n");
1657 		goto err_disable_clk;
1658 	}
1659 	disable_irq(dp->irq);
1660 
1661 	return dp;
1662 
1663 err_disable_clk:
1664 	clk_disable_unprepare(dp->clock);
1665 	return ERR_PTR(ret);
1666 }
1667 EXPORT_SYMBOL_GPL(analogix_dp_probe);
1668 
analogix_dp_suspend(struct analogix_dp_device * dp)1669 int analogix_dp_suspend(struct analogix_dp_device *dp)
1670 {
1671 	phy_power_off(dp->phy);
1672 
1673 	if (dp->plat_data->power_off)
1674 		dp->plat_data->power_off(dp->plat_data);
1675 
1676 	clk_disable_unprepare(dp->clock);
1677 
1678 	return 0;
1679 }
1680 EXPORT_SYMBOL_GPL(analogix_dp_suspend);
1681 
analogix_dp_resume(struct analogix_dp_device * dp)1682 int analogix_dp_resume(struct analogix_dp_device *dp)
1683 {
1684 	int ret;
1685 
1686 	ret = clk_prepare_enable(dp->clock);
1687 	if (ret < 0) {
1688 		DRM_ERROR("Failed to prepare_enable the clock clk [%d]\n", ret);
1689 		return ret;
1690 	}
1691 
1692 	if (dp->plat_data->power_on)
1693 		dp->plat_data->power_on(dp->plat_data);
1694 
1695 	phy_power_on(dp->phy);
1696 
1697 	analogix_dp_init_dp(dp);
1698 
1699 	return 0;
1700 }
1701 EXPORT_SYMBOL_GPL(analogix_dp_resume);
1702 
analogix_dp_bind(struct analogix_dp_device * dp,struct drm_device * drm_dev)1703 int analogix_dp_bind(struct analogix_dp_device *dp, struct drm_device *drm_dev)
1704 {
1705 	int ret;
1706 
1707 	dp->drm_dev = drm_dev;
1708 	dp->encoder = dp->plat_data->encoder;
1709 
1710 	if (IS_ENABLED(CONFIG_PM)) {
1711 		pm_runtime_use_autosuspend(dp->dev);
1712 		pm_runtime_set_autosuspend_delay(dp->dev, 100);
1713 		pm_runtime_enable(dp->dev);
1714 	} else {
1715 		ret = analogix_dp_resume(dp);
1716 		if (ret)
1717 			return ret;
1718 	}
1719 
1720 	dp->aux.name = "DP-AUX";
1721 	dp->aux.transfer = analogix_dpaux_transfer;
1722 	dp->aux.dev = dp->dev;
1723 	dp->aux.drm_dev = drm_dev;
1724 
1725 	ret = drm_dp_aux_register(&dp->aux);
1726 	if (ret) {
1727 		DRM_ERROR("failed to register AUX (%d)\n", ret);
1728 		goto err_disable_pm_runtime;
1729 	}
1730 
1731 	ret = analogix_dp_create_bridge(drm_dev, dp);
1732 	if (ret) {
1733 		DRM_ERROR("failed to create bridge (%d)\n", ret);
1734 		goto err_unregister_aux;
1735 	}
1736 
1737 	return 0;
1738 
1739 err_unregister_aux:
1740 	drm_dp_aux_unregister(&dp->aux);
1741 err_disable_pm_runtime:
1742 	if (IS_ENABLED(CONFIG_PM)) {
1743 		pm_runtime_dont_use_autosuspend(dp->dev);
1744 		pm_runtime_disable(dp->dev);
1745 	} else {
1746 		analogix_dp_suspend(dp);
1747 	}
1748 
1749 	return ret;
1750 }
1751 EXPORT_SYMBOL_GPL(analogix_dp_bind);
1752 
analogix_dp_unbind(struct analogix_dp_device * dp)1753 void analogix_dp_unbind(struct analogix_dp_device *dp)
1754 {
1755 	analogix_dp_bridge_disable(dp->bridge);
1756 	dp->connector.funcs->destroy(&dp->connector);
1757 
1758 	if (dp->plat_data->panel) {
1759 		if (drm_panel_unprepare(dp->plat_data->panel))
1760 			DRM_ERROR("failed to turnoff the panel\n");
1761 	}
1762 
1763 	drm_dp_aux_unregister(&dp->aux);
1764 
1765 	if (IS_ENABLED(CONFIG_PM)) {
1766 		pm_runtime_dont_use_autosuspend(dp->dev);
1767 		pm_runtime_disable(dp->dev);
1768 	} else {
1769 		analogix_dp_suspend(dp);
1770 	}
1771 }
1772 EXPORT_SYMBOL_GPL(analogix_dp_unbind);
1773 
analogix_dp_start_crc(struct drm_connector * connector)1774 int analogix_dp_start_crc(struct drm_connector *connector)
1775 {
1776 	struct analogix_dp_device *dp = to_dp(connector);
1777 
1778 	if (!connector->state->crtc) {
1779 		DRM_ERROR("Connector %s doesn't currently have a CRTC.\n",
1780 			  connector->name);
1781 		return -EINVAL;
1782 	}
1783 
1784 	return drm_dp_start_crc(&dp->aux, connector->state->crtc);
1785 }
1786 EXPORT_SYMBOL_GPL(analogix_dp_start_crc);
1787 
analogix_dp_stop_crc(struct drm_connector * connector)1788 int analogix_dp_stop_crc(struct drm_connector *connector)
1789 {
1790 	struct analogix_dp_device *dp = to_dp(connector);
1791 
1792 	return drm_dp_stop_crc(&dp->aux);
1793 }
1794 EXPORT_SYMBOL_GPL(analogix_dp_stop_crc);
1795 
1796 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
1797 MODULE_DESCRIPTION("Analogix DP Core Driver");
1798 MODULE_LICENSE("GPL v2");
1799