xref: /openbmc/linux/drivers/gpu/drm/msm/dsi/dsi_manager.c (revision 71de0a05)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015, The Linux Foundation. All rights reserved.
4  */
5 
6 #include "drm/drm_bridge_connector.h"
7 
8 #include "msm_kms.h"
9 #include "dsi.h"
10 
11 #define DSI_CLOCK_MASTER	DSI_0
12 #define DSI_CLOCK_SLAVE		DSI_1
13 
14 #define DSI_LEFT		DSI_0
15 #define DSI_RIGHT		DSI_1
16 
17 /* According to the current drm framework sequence, take the encoder of
18  * DSI_1 as master encoder
19  */
20 #define DSI_ENCODER_MASTER	DSI_1
21 #define DSI_ENCODER_SLAVE	DSI_0
22 
23 struct msm_dsi_manager {
24 	struct msm_dsi *dsi[DSI_MAX];
25 
26 	bool is_bonded_dsi;
27 	bool is_sync_needed;
28 	int master_dsi_link_id;
29 };
30 
31 static struct msm_dsi_manager msm_dsim_glb;
32 
33 #define IS_BONDED_DSI()		(msm_dsim_glb.is_bonded_dsi)
34 #define IS_SYNC_NEEDED()	(msm_dsim_glb.is_sync_needed)
35 #define IS_MASTER_DSI_LINK(id)	(msm_dsim_glb.master_dsi_link_id == id)
36 
37 #ifdef CONFIG_OF
38 static bool dsi_mgr_power_on_early(struct drm_bridge *bridge)
39 {
40 	struct drm_bridge *next_bridge = drm_bridge_get_next_bridge(bridge);
41 
42 	/*
43 	 * If the next bridge in the chain is the Parade ps8640 bridge chip
44 	 * then don't power on early since it seems to violate the expectations
45 	 * of the firmware that the bridge chip is running.
46 	 *
47 	 * NOTE: this is expected to be a temporary special case. It's expected
48 	 * that we'll eventually have a framework that allows the next level
49 	 * bridge to indicate whether it needs us to power on before it or
50 	 * after it. When that framework is in place then we'll use it and
51 	 * remove this special case.
52 	 */
53 	return !(next_bridge && next_bridge->of_node &&
54 		 of_device_is_compatible(next_bridge->of_node, "parade,ps8640"));
55 }
56 #else
57 static inline bool dsi_mgr_power_on_early(struct drm_bridge *bridge)
58 {
59 	return true;
60 }
61 #endif
62 
63 static inline struct msm_dsi *dsi_mgr_get_dsi(int id)
64 {
65 	return msm_dsim_glb.dsi[id];
66 }
67 
68 static inline struct msm_dsi *dsi_mgr_get_other_dsi(int id)
69 {
70 	return msm_dsim_glb.dsi[(id + 1) % DSI_MAX];
71 }
72 
73 static int dsi_mgr_parse_of(struct device_node *np, int id)
74 {
75 	struct msm_dsi_manager *msm_dsim = &msm_dsim_glb;
76 
77 	/* We assume 2 dsi nodes have the same information of bonded dsi and
78 	 * sync-mode, and only one node specifies master in case of bonded mode.
79 	 */
80 	if (!msm_dsim->is_bonded_dsi)
81 		msm_dsim->is_bonded_dsi = of_property_read_bool(np, "qcom,dual-dsi-mode");
82 
83 	if (msm_dsim->is_bonded_dsi) {
84 		if (of_property_read_bool(np, "qcom,master-dsi"))
85 			msm_dsim->master_dsi_link_id = id;
86 		if (!msm_dsim->is_sync_needed)
87 			msm_dsim->is_sync_needed = of_property_read_bool(
88 					np, "qcom,sync-dual-dsi");
89 	}
90 
91 	return 0;
92 }
93 
94 static int dsi_mgr_setup_components(int id)
95 {
96 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
97 	struct msm_dsi *other_dsi = dsi_mgr_get_other_dsi(id);
98 	struct msm_dsi *clk_master_dsi = dsi_mgr_get_dsi(DSI_CLOCK_MASTER);
99 	struct msm_dsi *clk_slave_dsi = dsi_mgr_get_dsi(DSI_CLOCK_SLAVE);
100 	int ret;
101 
102 	if (!IS_BONDED_DSI()) {
103 		ret = msm_dsi_host_register(msm_dsi->host);
104 		if (ret)
105 			return ret;
106 
107 		msm_dsi_phy_set_usecase(msm_dsi->phy, MSM_DSI_PHY_STANDALONE);
108 		msm_dsi_host_set_phy_mode(msm_dsi->host, msm_dsi->phy);
109 	} else if (other_dsi) {
110 		struct msm_dsi *master_link_dsi = IS_MASTER_DSI_LINK(id) ?
111 							msm_dsi : other_dsi;
112 		struct msm_dsi *slave_link_dsi = IS_MASTER_DSI_LINK(id) ?
113 							other_dsi : msm_dsi;
114 		/* Register slave host first, so that slave DSI device
115 		 * has a chance to probe, and do not block the master
116 		 * DSI device's probe.
117 		 * Also, do not check defer for the slave host,
118 		 * because only master DSI device adds the panel to global
119 		 * panel list. The panel's device is the master DSI device.
120 		 */
121 		ret = msm_dsi_host_register(slave_link_dsi->host);
122 		if (ret)
123 			return ret;
124 		ret = msm_dsi_host_register(master_link_dsi->host);
125 		if (ret)
126 			return ret;
127 
128 		/* PLL0 is to drive both 2 DSI link clocks in bonded DSI mode. */
129 		msm_dsi_phy_set_usecase(clk_master_dsi->phy,
130 					MSM_DSI_PHY_MASTER);
131 		msm_dsi_phy_set_usecase(clk_slave_dsi->phy,
132 					MSM_DSI_PHY_SLAVE);
133 		msm_dsi_host_set_phy_mode(msm_dsi->host, msm_dsi->phy);
134 		msm_dsi_host_set_phy_mode(other_dsi->host, other_dsi->phy);
135 	}
136 
137 	return 0;
138 }
139 
140 static int enable_phy(struct msm_dsi *msm_dsi,
141 		      struct msm_dsi_phy_shared_timings *shared_timings)
142 {
143 	struct msm_dsi_phy_clk_request clk_req;
144 	bool is_bonded_dsi = IS_BONDED_DSI();
145 
146 	msm_dsi_host_get_phy_clk_req(msm_dsi->host, &clk_req, is_bonded_dsi);
147 
148 	return msm_dsi_phy_enable(msm_dsi->phy, &clk_req, shared_timings);
149 }
150 
151 static int
152 dsi_mgr_phy_enable(int id,
153 		   struct msm_dsi_phy_shared_timings shared_timings[DSI_MAX])
154 {
155 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
156 	struct msm_dsi *mdsi = dsi_mgr_get_dsi(DSI_CLOCK_MASTER);
157 	struct msm_dsi *sdsi = dsi_mgr_get_dsi(DSI_CLOCK_SLAVE);
158 	int ret;
159 
160 	/* In case of bonded DSI, some registers in PHY1 have been programmed
161 	 * during PLL0 clock's set_rate. The PHY1 reset called by host1 here
162 	 * will silently reset those PHY1 registers. Therefore we need to reset
163 	 * and enable both PHYs before any PLL clock operation.
164 	 */
165 	if (IS_BONDED_DSI() && mdsi && sdsi) {
166 		if (!mdsi->phy_enabled && !sdsi->phy_enabled) {
167 			msm_dsi_host_reset_phy(mdsi->host);
168 			msm_dsi_host_reset_phy(sdsi->host);
169 
170 			ret = enable_phy(mdsi,
171 					 &shared_timings[DSI_CLOCK_MASTER]);
172 			if (ret)
173 				return ret;
174 			ret = enable_phy(sdsi,
175 					 &shared_timings[DSI_CLOCK_SLAVE]);
176 			if (ret) {
177 				msm_dsi_phy_disable(mdsi->phy);
178 				return ret;
179 			}
180 		}
181 	} else {
182 		msm_dsi_host_reset_phy(msm_dsi->host);
183 		ret = enable_phy(msm_dsi, &shared_timings[id]);
184 		if (ret)
185 			return ret;
186 	}
187 
188 	msm_dsi->phy_enabled = true;
189 
190 	return 0;
191 }
192 
193 static void dsi_mgr_phy_disable(int id)
194 {
195 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
196 	struct msm_dsi *mdsi = dsi_mgr_get_dsi(DSI_CLOCK_MASTER);
197 	struct msm_dsi *sdsi = dsi_mgr_get_dsi(DSI_CLOCK_SLAVE);
198 
199 	/* disable DSI phy
200 	 * In bonded dsi configuration, the phy should be disabled for the
201 	 * first controller only when the second controller is disabled.
202 	 */
203 	msm_dsi->phy_enabled = false;
204 	if (IS_BONDED_DSI() && mdsi && sdsi) {
205 		if (!mdsi->phy_enabled && !sdsi->phy_enabled) {
206 			msm_dsi_phy_disable(sdsi->phy);
207 			msm_dsi_phy_disable(mdsi->phy);
208 		}
209 	} else {
210 		msm_dsi_phy_disable(msm_dsi->phy);
211 	}
212 }
213 
214 struct dsi_bridge {
215 	struct drm_bridge base;
216 	int id;
217 };
218 
219 #define to_dsi_bridge(x) container_of(x, struct dsi_bridge, base)
220 
221 static int dsi_mgr_bridge_get_id(struct drm_bridge *bridge)
222 {
223 	struct dsi_bridge *dsi_bridge = to_dsi_bridge(bridge);
224 	return dsi_bridge->id;
225 }
226 
227 static void msm_dsi_manager_set_split_display(u8 id)
228 {
229 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
230 	struct msm_dsi *other_dsi = dsi_mgr_get_other_dsi(id);
231 	struct msm_drm_private *priv = msm_dsi->dev->dev_private;
232 	struct msm_kms *kms = priv->kms;
233 	struct msm_dsi *master_dsi, *slave_dsi;
234 
235 	if (IS_BONDED_DSI() && !IS_MASTER_DSI_LINK(id)) {
236 		master_dsi = other_dsi;
237 		slave_dsi = msm_dsi;
238 	} else {
239 		master_dsi = msm_dsi;
240 		slave_dsi = other_dsi;
241 	}
242 
243 	if (!msm_dsi->external_bridge || !IS_BONDED_DSI())
244 		return;
245 
246 	/*
247 	 * Set split display info to kms once bonded DSI panel is connected to
248 	 * both hosts.
249 	 */
250 	if (other_dsi && other_dsi->external_bridge && kms->funcs->set_split_display) {
251 		kms->funcs->set_split_display(kms, master_dsi->encoder,
252 					      slave_dsi->encoder,
253 					      msm_dsi_is_cmd_mode(msm_dsi));
254 	}
255 }
256 
257 static void dsi_mgr_bridge_power_on(struct drm_bridge *bridge)
258 {
259 	int id = dsi_mgr_bridge_get_id(bridge);
260 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
261 	struct msm_dsi *msm_dsi1 = dsi_mgr_get_dsi(DSI_1);
262 	struct mipi_dsi_host *host = msm_dsi->host;
263 	struct msm_dsi_phy_shared_timings phy_shared_timings[DSI_MAX];
264 	bool is_bonded_dsi = IS_BONDED_DSI();
265 	int ret;
266 
267 	DBG("id=%d", id);
268 	if (!msm_dsi_device_connected(msm_dsi))
269 		return;
270 
271 	/* Do nothing with the host if it is slave-DSI in case of bonded DSI */
272 	if (is_bonded_dsi && !IS_MASTER_DSI_LINK(id))
273 		return;
274 
275 	ret = dsi_mgr_phy_enable(id, phy_shared_timings);
276 	if (ret)
277 		goto phy_en_fail;
278 
279 	ret = msm_dsi_host_power_on(host, &phy_shared_timings[id], is_bonded_dsi, msm_dsi->phy);
280 	if (ret) {
281 		pr_err("%s: power on host %d failed, %d\n", __func__, id, ret);
282 		goto host_on_fail;
283 	}
284 
285 	if (is_bonded_dsi && msm_dsi1) {
286 		ret = msm_dsi_host_power_on(msm_dsi1->host,
287 				&phy_shared_timings[DSI_1], is_bonded_dsi, msm_dsi1->phy);
288 		if (ret) {
289 			pr_err("%s: power on host1 failed, %d\n",
290 							__func__, ret);
291 			goto host1_on_fail;
292 		}
293 	}
294 
295 	/*
296 	 * Enable before preparing the panel, disable after unpreparing, so
297 	 * that the panel can communicate over the DSI link.
298 	 */
299 	msm_dsi_host_enable_irq(host);
300 	if (is_bonded_dsi && msm_dsi1)
301 		msm_dsi_host_enable_irq(msm_dsi1->host);
302 
303 	return;
304 
305 host1_on_fail:
306 	msm_dsi_host_power_off(host);
307 host_on_fail:
308 	dsi_mgr_phy_disable(id);
309 phy_en_fail:
310 	return;
311 }
312 
313 static void dsi_mgr_bridge_pre_enable(struct drm_bridge *bridge)
314 {
315 	int id = dsi_mgr_bridge_get_id(bridge);
316 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
317 	struct msm_dsi *msm_dsi1 = dsi_mgr_get_dsi(DSI_1);
318 	struct mipi_dsi_host *host = msm_dsi->host;
319 	bool is_bonded_dsi = IS_BONDED_DSI();
320 	int ret;
321 
322 	DBG("id=%d", id);
323 	if (!msm_dsi_device_connected(msm_dsi))
324 		return;
325 
326 	/* Do nothing with the host if it is slave-DSI in case of bonded DSI */
327 	if (is_bonded_dsi && !IS_MASTER_DSI_LINK(id))
328 		return;
329 
330 	if (!dsi_mgr_power_on_early(bridge))
331 		dsi_mgr_bridge_power_on(bridge);
332 
333 	ret = msm_dsi_host_enable(host);
334 	if (ret) {
335 		pr_err("%s: enable host %d failed, %d\n", __func__, id, ret);
336 		goto host_en_fail;
337 	}
338 
339 	if (is_bonded_dsi && msm_dsi1) {
340 		ret = msm_dsi_host_enable(msm_dsi1->host);
341 		if (ret) {
342 			pr_err("%s: enable host1 failed, %d\n", __func__, ret);
343 			goto host1_en_fail;
344 		}
345 	}
346 
347 	return;
348 
349 host1_en_fail:
350 	msm_dsi_host_disable(host);
351 host_en_fail:
352 
353 	return;
354 }
355 
356 void msm_dsi_manager_tpg_enable(void)
357 {
358 	struct msm_dsi *m_dsi = dsi_mgr_get_dsi(DSI_0);
359 	struct msm_dsi *s_dsi = dsi_mgr_get_dsi(DSI_1);
360 
361 	/* if dual dsi, trigger tpg on master first then slave */
362 	if (m_dsi) {
363 		msm_dsi_host_test_pattern_en(m_dsi->host);
364 		if (IS_BONDED_DSI() && s_dsi)
365 			msm_dsi_host_test_pattern_en(s_dsi->host);
366 	}
367 }
368 
369 static void dsi_mgr_bridge_post_disable(struct drm_bridge *bridge)
370 {
371 	int id = dsi_mgr_bridge_get_id(bridge);
372 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
373 	struct msm_dsi *msm_dsi1 = dsi_mgr_get_dsi(DSI_1);
374 	struct mipi_dsi_host *host = msm_dsi->host;
375 	bool is_bonded_dsi = IS_BONDED_DSI();
376 	int ret;
377 
378 	DBG("id=%d", id);
379 
380 	if (!msm_dsi_device_connected(msm_dsi))
381 		return;
382 
383 	/*
384 	 * Do nothing with the host if it is slave-DSI in case of bonded DSI.
385 	 * It is safe to call dsi_mgr_phy_disable() here because a single PHY
386 	 * won't be diabled until both PHYs request disable.
387 	 */
388 	if (is_bonded_dsi && !IS_MASTER_DSI_LINK(id))
389 		goto disable_phy;
390 
391 	ret = msm_dsi_host_disable(host);
392 	if (ret)
393 		pr_err("%s: host %d disable failed, %d\n", __func__, id, ret);
394 
395 	if (is_bonded_dsi && msm_dsi1) {
396 		ret = msm_dsi_host_disable(msm_dsi1->host);
397 		if (ret)
398 			pr_err("%s: host1 disable failed, %d\n", __func__, ret);
399 	}
400 
401 	msm_dsi_host_disable_irq(host);
402 	if (is_bonded_dsi && msm_dsi1)
403 		msm_dsi_host_disable_irq(msm_dsi1->host);
404 
405 	/* Save PHY status if it is a clock source */
406 	msm_dsi_phy_pll_save_state(msm_dsi->phy);
407 
408 	ret = msm_dsi_host_power_off(host);
409 	if (ret)
410 		pr_err("%s: host %d power off failed,%d\n", __func__, id, ret);
411 
412 	if (is_bonded_dsi && msm_dsi1) {
413 		ret = msm_dsi_host_power_off(msm_dsi1->host);
414 		if (ret)
415 			pr_err("%s: host1 power off failed, %d\n",
416 								__func__, ret);
417 	}
418 
419 disable_phy:
420 	dsi_mgr_phy_disable(id);
421 }
422 
423 static void dsi_mgr_bridge_mode_set(struct drm_bridge *bridge,
424 		const struct drm_display_mode *mode,
425 		const struct drm_display_mode *adjusted_mode)
426 {
427 	int id = dsi_mgr_bridge_get_id(bridge);
428 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
429 	struct msm_dsi *other_dsi = dsi_mgr_get_other_dsi(id);
430 	struct mipi_dsi_host *host = msm_dsi->host;
431 	bool is_bonded_dsi = IS_BONDED_DSI();
432 
433 	DBG("set mode: " DRM_MODE_FMT, DRM_MODE_ARG(mode));
434 
435 	if (is_bonded_dsi && !IS_MASTER_DSI_LINK(id))
436 		return;
437 
438 	msm_dsi_host_set_display_mode(host, adjusted_mode);
439 	if (is_bonded_dsi && other_dsi)
440 		msm_dsi_host_set_display_mode(other_dsi->host, adjusted_mode);
441 
442 	if (dsi_mgr_power_on_early(bridge))
443 		dsi_mgr_bridge_power_on(bridge);
444 }
445 
446 static enum drm_mode_status dsi_mgr_bridge_mode_valid(struct drm_bridge *bridge,
447 						      const struct drm_display_info *info,
448 						      const struct drm_display_mode *mode)
449 {
450 	int id = dsi_mgr_bridge_get_id(bridge);
451 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
452 	struct mipi_dsi_host *host = msm_dsi->host;
453 	struct platform_device *pdev = msm_dsi->pdev;
454 	struct dev_pm_opp *opp;
455 	unsigned long byte_clk_rate;
456 
457 	byte_clk_rate = dsi_byte_clk_get_rate(host, IS_BONDED_DSI(), mode);
458 
459 	opp = dev_pm_opp_find_freq_ceil(&pdev->dev, &byte_clk_rate);
460 	if (!IS_ERR(opp)) {
461 		dev_pm_opp_put(opp);
462 	} else if (PTR_ERR(opp) == -ERANGE) {
463 		/*
464 		 * An empty table is created by devm_pm_opp_set_clkname() even
465 		 * if there is none. Thus find_freq_ceil will still return
466 		 * -ERANGE in such case.
467 		 */
468 		if (dev_pm_opp_get_opp_count(&pdev->dev) != 0)
469 			return MODE_CLOCK_RANGE;
470 	} else {
471 			return MODE_ERROR;
472 	}
473 
474 	return msm_dsi_host_check_dsc(host, mode);
475 }
476 
477 static const struct drm_bridge_funcs dsi_mgr_bridge_funcs = {
478 	.pre_enable = dsi_mgr_bridge_pre_enable,
479 	.post_disable = dsi_mgr_bridge_post_disable,
480 	.mode_set = dsi_mgr_bridge_mode_set,
481 	.mode_valid = dsi_mgr_bridge_mode_valid,
482 };
483 
484 /* initialize bridge */
485 struct drm_bridge *msm_dsi_manager_bridge_init(u8 id)
486 {
487 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
488 	struct drm_bridge *bridge = NULL;
489 	struct dsi_bridge *dsi_bridge;
490 	struct drm_encoder *encoder;
491 	int ret;
492 
493 	dsi_bridge = devm_kzalloc(msm_dsi->dev->dev,
494 				sizeof(*dsi_bridge), GFP_KERNEL);
495 	if (!dsi_bridge) {
496 		ret = -ENOMEM;
497 		goto fail;
498 	}
499 
500 	dsi_bridge->id = id;
501 
502 	encoder = msm_dsi->encoder;
503 
504 	bridge = &dsi_bridge->base;
505 	bridge->funcs = &dsi_mgr_bridge_funcs;
506 
507 	drm_bridge_add(bridge);
508 
509 	ret = drm_bridge_attach(encoder, bridge, NULL, 0);
510 	if (ret)
511 		goto fail;
512 
513 	return bridge;
514 
515 fail:
516 	if (bridge)
517 		msm_dsi_manager_bridge_destroy(bridge);
518 
519 	return ERR_PTR(ret);
520 }
521 
522 int msm_dsi_manager_ext_bridge_init(u8 id)
523 {
524 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
525 	struct drm_device *dev = msm_dsi->dev;
526 	struct drm_encoder *encoder;
527 	struct drm_bridge *int_bridge, *ext_bridge;
528 	int ret;
529 
530 	int_bridge = msm_dsi->bridge;
531 	ext_bridge = devm_drm_of_get_bridge(&msm_dsi->pdev->dev,
532 					    msm_dsi->pdev->dev.of_node, 1, 0);
533 	if (IS_ERR(ext_bridge))
534 		return PTR_ERR(ext_bridge);
535 
536 	msm_dsi->external_bridge = ext_bridge;
537 
538 	encoder = msm_dsi->encoder;
539 
540 	/*
541 	 * Try first to create the bridge without it creating its own
542 	 * connector.. currently some bridges support this, and others
543 	 * do not (and some support both modes)
544 	 */
545 	ret = drm_bridge_attach(encoder, ext_bridge, int_bridge,
546 			DRM_BRIDGE_ATTACH_NO_CONNECTOR);
547 	if (ret == -EINVAL) {
548 		/*
549 		 * link the internal dsi bridge to the external bridge,
550 		 * connector is created by the next bridge.
551 		 */
552 		ret = drm_bridge_attach(encoder, ext_bridge, int_bridge, 0);
553 		if (ret < 0)
554 			return ret;
555 	} else {
556 		struct drm_connector *connector;
557 
558 		/* We are in charge of the connector, create one now. */
559 		connector = drm_bridge_connector_init(dev, encoder);
560 		if (IS_ERR(connector)) {
561 			DRM_ERROR("Unable to create bridge connector\n");
562 			return PTR_ERR(connector);
563 		}
564 
565 		ret = drm_connector_attach_encoder(connector, encoder);
566 		if (ret < 0)
567 			return ret;
568 	}
569 
570 	/* The pipeline is ready, ping encoders if necessary */
571 	msm_dsi_manager_set_split_display(id);
572 
573 	return 0;
574 }
575 
576 void msm_dsi_manager_bridge_destroy(struct drm_bridge *bridge)
577 {
578 	drm_bridge_remove(bridge);
579 }
580 
581 int msm_dsi_manager_cmd_xfer(int id, const struct mipi_dsi_msg *msg)
582 {
583 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
584 	struct msm_dsi *msm_dsi0 = dsi_mgr_get_dsi(DSI_0);
585 	struct mipi_dsi_host *host = msm_dsi->host;
586 	bool is_read = (msg->rx_buf && msg->rx_len);
587 	bool need_sync = (IS_SYNC_NEEDED() && !is_read);
588 	int ret;
589 
590 	if (!msg->tx_buf || !msg->tx_len)
591 		return 0;
592 
593 	/* In bonded master case, panel requires the same commands sent to
594 	 * both DSI links. Host issues the command trigger to both links
595 	 * when DSI_1 calls the cmd transfer function, no matter it happens
596 	 * before or after DSI_0 cmd transfer.
597 	 */
598 	if (need_sync && (id == DSI_0))
599 		return is_read ? msg->rx_len : msg->tx_len;
600 
601 	if (need_sync && msm_dsi0) {
602 		ret = msm_dsi_host_xfer_prepare(msm_dsi0->host, msg);
603 		if (ret) {
604 			pr_err("%s: failed to prepare non-trigger host, %d\n",
605 				__func__, ret);
606 			return ret;
607 		}
608 	}
609 	ret = msm_dsi_host_xfer_prepare(host, msg);
610 	if (ret) {
611 		pr_err("%s: failed to prepare host, %d\n", __func__, ret);
612 		goto restore_host0;
613 	}
614 
615 	ret = is_read ? msm_dsi_host_cmd_rx(host, msg) :
616 			msm_dsi_host_cmd_tx(host, msg);
617 
618 	msm_dsi_host_xfer_restore(host, msg);
619 
620 restore_host0:
621 	if (need_sync && msm_dsi0)
622 		msm_dsi_host_xfer_restore(msm_dsi0->host, msg);
623 
624 	return ret;
625 }
626 
627 bool msm_dsi_manager_cmd_xfer_trigger(int id, u32 dma_base, u32 len)
628 {
629 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
630 	struct msm_dsi *msm_dsi0 = dsi_mgr_get_dsi(DSI_0);
631 	struct mipi_dsi_host *host = msm_dsi->host;
632 
633 	if (IS_SYNC_NEEDED() && (id == DSI_0))
634 		return false;
635 
636 	if (IS_SYNC_NEEDED() && msm_dsi0)
637 		msm_dsi_host_cmd_xfer_commit(msm_dsi0->host, dma_base, len);
638 
639 	msm_dsi_host_cmd_xfer_commit(host, dma_base, len);
640 
641 	return true;
642 }
643 
644 int msm_dsi_manager_register(struct msm_dsi *msm_dsi)
645 {
646 	struct msm_dsi_manager *msm_dsim = &msm_dsim_glb;
647 	int id = msm_dsi->id;
648 	int ret;
649 
650 	if (id >= DSI_MAX) {
651 		pr_err("%s: invalid id %d\n", __func__, id);
652 		return -EINVAL;
653 	}
654 
655 	if (msm_dsim->dsi[id]) {
656 		pr_err("%s: dsi%d already registered\n", __func__, id);
657 		return -EBUSY;
658 	}
659 
660 	msm_dsim->dsi[id] = msm_dsi;
661 
662 	ret = dsi_mgr_parse_of(msm_dsi->pdev->dev.of_node, id);
663 	if (ret) {
664 		pr_err("%s: failed to parse OF DSI info\n", __func__);
665 		goto fail;
666 	}
667 
668 	ret = dsi_mgr_setup_components(id);
669 	if (ret) {
670 		pr_err("%s: failed to register mipi dsi host for DSI %d: %d\n",
671 			__func__, id, ret);
672 		goto fail;
673 	}
674 
675 	return 0;
676 
677 fail:
678 	msm_dsim->dsi[id] = NULL;
679 	return ret;
680 }
681 
682 void msm_dsi_manager_unregister(struct msm_dsi *msm_dsi)
683 {
684 	struct msm_dsi_manager *msm_dsim = &msm_dsim_glb;
685 
686 	if (msm_dsi->host)
687 		msm_dsi_host_unregister(msm_dsi->host);
688 
689 	if (msm_dsi->id >= 0)
690 		msm_dsim->dsi[msm_dsi->id] = NULL;
691 }
692 
693 bool msm_dsi_is_bonded_dsi(struct msm_dsi *msm_dsi)
694 {
695 	return IS_BONDED_DSI();
696 }
697 
698 bool msm_dsi_is_master_dsi(struct msm_dsi *msm_dsi)
699 {
700 	return IS_MASTER_DSI_LINK(msm_dsi->id);
701 }
702