xref: /linux/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 Red Hat
4  * Author: Rob Clark <robdclark@gmail.com>
5  */
6 
7 #include <linux/delay.h>
8 
9 #include <drm/drm_vblank.h>
10 
11 #include "msm_drv.h"
12 #include "msm_gem.h"
13 #include "msm_mmu.h"
14 #include "mdp4_kms.h"
15 
16 static int mdp4_hw_init(struct msm_kms *kms)
17 {
18 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
19 	struct drm_device *dev = mdp4_kms->dev;
20 	u32 dmap_cfg, vg_cfg;
21 	unsigned long clk;
22 
23 	pm_runtime_get_sync(dev->dev);
24 
25 	if (mdp4_kms->rev > 1) {
26 		mdp4_write(mdp4_kms, REG_MDP4_CS_CONTROLLER0, 0x0707ffff);
27 		mdp4_write(mdp4_kms, REG_MDP4_CS_CONTROLLER1, 0x03073f3f);
28 	}
29 
30 	mdp4_write(mdp4_kms, REG_MDP4_PORTMAP_MODE, 0x3);
31 
32 	/* max read pending cmd config, 3 pending requests: */
33 	mdp4_write(mdp4_kms, REG_MDP4_READ_CNFG, 0x02222);
34 
35 	clk = clk_get_rate(mdp4_kms->clk);
36 
37 	if ((mdp4_kms->rev >= 1) || (clk >= 90000000)) {
38 		dmap_cfg = 0x47;     /* 16 bytes-burst x 8 req */
39 		vg_cfg = 0x47;       /* 16 bytes-burs x 8 req */
40 	} else {
41 		dmap_cfg = 0x27;     /* 8 bytes-burst x 8 req */
42 		vg_cfg = 0x43;       /* 16 bytes-burst x 4 req */
43 	}
44 
45 	DBG("fetch config: dmap=%02x, vg=%02x", dmap_cfg, vg_cfg);
46 
47 	mdp4_write(mdp4_kms, REG_MDP4_DMA_FETCH_CONFIG(DMA_P), dmap_cfg);
48 	mdp4_write(mdp4_kms, REG_MDP4_DMA_FETCH_CONFIG(DMA_E), dmap_cfg);
49 
50 	mdp4_write(mdp4_kms, REG_MDP4_PIPE_FETCH_CONFIG(VG1), vg_cfg);
51 	mdp4_write(mdp4_kms, REG_MDP4_PIPE_FETCH_CONFIG(VG2), vg_cfg);
52 	mdp4_write(mdp4_kms, REG_MDP4_PIPE_FETCH_CONFIG(RGB1), vg_cfg);
53 	mdp4_write(mdp4_kms, REG_MDP4_PIPE_FETCH_CONFIG(RGB2), vg_cfg);
54 
55 	if (mdp4_kms->rev >= 2)
56 		mdp4_write(mdp4_kms, REG_MDP4_LAYERMIXER_IN_CFG_UPDATE_METHOD, 1);
57 	mdp4_write(mdp4_kms, REG_MDP4_LAYERMIXER_IN_CFG, 0);
58 
59 	/* disable CSC matrix / YUV by default: */
60 	mdp4_write(mdp4_kms, REG_MDP4_PIPE_OP_MODE(VG1), 0);
61 	mdp4_write(mdp4_kms, REG_MDP4_PIPE_OP_MODE(VG2), 0);
62 	mdp4_write(mdp4_kms, REG_MDP4_DMA_P_OP_MODE, 0);
63 	mdp4_write(mdp4_kms, REG_MDP4_DMA_S_OP_MODE, 0);
64 	mdp4_write(mdp4_kms, REG_MDP4_OVLP_CSC_CONFIG(1), 0);
65 	mdp4_write(mdp4_kms, REG_MDP4_OVLP_CSC_CONFIG(2), 0);
66 
67 	if (mdp4_kms->rev > 1)
68 		mdp4_write(mdp4_kms, REG_MDP4_RESET_STATUS, 1);
69 
70 	pm_runtime_put_sync(dev->dev);
71 
72 	return 0;
73 }
74 
75 static void mdp4_enable_commit(struct msm_kms *kms)
76 {
77 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
78 	mdp4_enable(mdp4_kms);
79 }
80 
81 static void mdp4_disable_commit(struct msm_kms *kms)
82 {
83 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
84 	mdp4_disable(mdp4_kms);
85 }
86 
87 static void mdp4_flush_commit(struct msm_kms *kms, unsigned crtc_mask)
88 {
89 	/* TODO */
90 }
91 
92 static void mdp4_wait_flush(struct msm_kms *kms, unsigned crtc_mask)
93 {
94 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
95 	struct drm_crtc *crtc;
96 
97 	for_each_crtc_mask(mdp4_kms->dev, crtc, crtc_mask)
98 		mdp4_crtc_wait_for_commit_done(crtc);
99 }
100 
101 static void mdp4_complete_commit(struct msm_kms *kms, unsigned crtc_mask)
102 {
103 }
104 
105 static long mdp4_round_pixclk(struct msm_kms *kms, unsigned long rate,
106 		struct drm_encoder *encoder)
107 {
108 	/* if we had >1 encoder, we'd need something more clever: */
109 	switch (encoder->encoder_type) {
110 	case DRM_MODE_ENCODER_TMDS:
111 		return mdp4_dtv_round_pixclk(encoder, rate);
112 	case DRM_MODE_ENCODER_LVDS:
113 	case DRM_MODE_ENCODER_DSI:
114 	default:
115 		return rate;
116 	}
117 }
118 
119 static void mdp4_destroy(struct msm_kms *kms)
120 {
121 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
122 	struct device *dev = mdp4_kms->dev->dev;
123 	struct msm_gem_address_space *aspace = kms->aspace;
124 
125 	if (mdp4_kms->blank_cursor_iova)
126 		msm_gem_unpin_iova(mdp4_kms->blank_cursor_bo, kms->aspace);
127 	drm_gem_object_put(mdp4_kms->blank_cursor_bo);
128 
129 	if (aspace) {
130 		aspace->mmu->funcs->detach(aspace->mmu);
131 		msm_gem_address_space_put(aspace);
132 	}
133 
134 	if (mdp4_kms->rpm_enabled)
135 		pm_runtime_disable(dev);
136 
137 	mdp_kms_destroy(&mdp4_kms->base);
138 }
139 
140 static const struct mdp_kms_funcs kms_funcs = {
141 	.base = {
142 		.hw_init         = mdp4_hw_init,
143 		.irq_preinstall  = mdp4_irq_preinstall,
144 		.irq_postinstall = mdp4_irq_postinstall,
145 		.irq_uninstall   = mdp4_irq_uninstall,
146 		.irq             = mdp4_irq,
147 		.enable_vblank   = mdp4_enable_vblank,
148 		.disable_vblank  = mdp4_disable_vblank,
149 		.enable_commit   = mdp4_enable_commit,
150 		.disable_commit  = mdp4_disable_commit,
151 		.flush_commit    = mdp4_flush_commit,
152 		.wait_flush      = mdp4_wait_flush,
153 		.complete_commit = mdp4_complete_commit,
154 		.round_pixclk    = mdp4_round_pixclk,
155 		.destroy         = mdp4_destroy,
156 	},
157 	.set_irqmask         = mdp4_set_irqmask,
158 };
159 
160 int mdp4_disable(struct mdp4_kms *mdp4_kms)
161 {
162 	DBG("");
163 
164 	clk_disable_unprepare(mdp4_kms->clk);
165 	clk_disable_unprepare(mdp4_kms->pclk);
166 	clk_disable_unprepare(mdp4_kms->lut_clk);
167 	clk_disable_unprepare(mdp4_kms->axi_clk);
168 
169 	return 0;
170 }
171 
172 int mdp4_enable(struct mdp4_kms *mdp4_kms)
173 {
174 	DBG("");
175 
176 	clk_prepare_enable(mdp4_kms->clk);
177 	clk_prepare_enable(mdp4_kms->pclk);
178 	clk_prepare_enable(mdp4_kms->lut_clk);
179 	clk_prepare_enable(mdp4_kms->axi_clk);
180 
181 	return 0;
182 }
183 
184 
185 static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
186 				  int intf_type)
187 {
188 	struct drm_device *dev = mdp4_kms->dev;
189 	struct msm_drm_private *priv = dev->dev_private;
190 	struct drm_encoder *encoder;
191 	struct drm_connector *connector;
192 	struct device_node *panel_node;
193 	int dsi_id;
194 	int ret;
195 
196 	switch (intf_type) {
197 	case DRM_MODE_ENCODER_LVDS:
198 		/*
199 		 * bail out early if there is no panel node (no need to
200 		 * initialize LCDC encoder and LVDS connector)
201 		 */
202 		panel_node = of_graph_get_remote_node(dev->dev->of_node, 0, 0);
203 		if (!panel_node)
204 			return 0;
205 
206 		encoder = mdp4_lcdc_encoder_init(dev, panel_node);
207 		if (IS_ERR(encoder)) {
208 			DRM_DEV_ERROR(dev->dev, "failed to construct LCDC encoder\n");
209 			of_node_put(panel_node);
210 			return PTR_ERR(encoder);
211 		}
212 
213 		/* LCDC can be hooked to DMA_P (TODO: Add DMA_S later?) */
214 		encoder->possible_crtcs = 1 << DMA_P;
215 
216 		connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
217 		if (IS_ERR(connector)) {
218 			DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS connector\n");
219 			of_node_put(panel_node);
220 			return PTR_ERR(connector);
221 		}
222 
223 		break;
224 	case DRM_MODE_ENCODER_TMDS:
225 		encoder = mdp4_dtv_encoder_init(dev);
226 		if (IS_ERR(encoder)) {
227 			DRM_DEV_ERROR(dev->dev, "failed to construct DTV encoder\n");
228 			return PTR_ERR(encoder);
229 		}
230 
231 		/* DTV can be hooked to DMA_E: */
232 		encoder->possible_crtcs = 1 << 1;
233 
234 		if (priv->hdmi) {
235 			/* Construct bridge/connector for HDMI: */
236 			ret = msm_hdmi_modeset_init(priv->hdmi, dev, encoder);
237 			if (ret) {
238 				DRM_DEV_ERROR(dev->dev, "failed to initialize HDMI: %d\n", ret);
239 				return ret;
240 			}
241 		}
242 
243 		break;
244 	case DRM_MODE_ENCODER_DSI:
245 		/* only DSI1 supported for now */
246 		dsi_id = 0;
247 
248 		if (!priv->dsi[dsi_id])
249 			break;
250 
251 		encoder = mdp4_dsi_encoder_init(dev);
252 		if (IS_ERR(encoder)) {
253 			ret = PTR_ERR(encoder);
254 			DRM_DEV_ERROR(dev->dev,
255 				"failed to construct DSI encoder: %d\n", ret);
256 			return ret;
257 		}
258 
259 		/* TODO: Add DMA_S later? */
260 		encoder->possible_crtcs = 1 << DMA_P;
261 
262 		ret = msm_dsi_modeset_init(priv->dsi[dsi_id], dev, encoder);
263 		if (ret) {
264 			DRM_DEV_ERROR(dev->dev, "failed to initialize DSI: %d\n",
265 				ret);
266 			return ret;
267 		}
268 
269 		break;
270 	default:
271 		DRM_DEV_ERROR(dev->dev, "Invalid or unsupported interface\n");
272 		return -EINVAL;
273 	}
274 
275 	return 0;
276 }
277 
278 static int modeset_init(struct mdp4_kms *mdp4_kms)
279 {
280 	struct drm_device *dev = mdp4_kms->dev;
281 	struct msm_drm_private *priv = dev->dev_private;
282 	struct drm_plane *plane;
283 	struct drm_crtc *crtc;
284 	int i, ret;
285 	static const enum mdp4_pipe rgb_planes[] = {
286 		RGB1, RGB2,
287 	};
288 	static const enum mdp4_pipe vg_planes[] = {
289 		VG1, VG2,
290 	};
291 	static const enum mdp4_dma mdp4_crtcs[] = {
292 		DMA_P, DMA_E,
293 	};
294 	static const char * const mdp4_crtc_names[] = {
295 		"DMA_P", "DMA_E",
296 	};
297 	static const int mdp4_intfs[] = {
298 		DRM_MODE_ENCODER_LVDS,
299 		DRM_MODE_ENCODER_DSI,
300 		DRM_MODE_ENCODER_TMDS,
301 	};
302 
303 	/* construct non-private planes: */
304 	for (i = 0; i < ARRAY_SIZE(vg_planes); i++) {
305 		plane = mdp4_plane_init(dev, vg_planes[i], false);
306 		if (IS_ERR(plane)) {
307 			DRM_DEV_ERROR(dev->dev,
308 				"failed to construct plane for VG%d\n", i + 1);
309 			ret = PTR_ERR(plane);
310 			goto fail;
311 		}
312 	}
313 
314 	for (i = 0; i < ARRAY_SIZE(mdp4_crtcs); i++) {
315 		plane = mdp4_plane_init(dev, rgb_planes[i], true);
316 		if (IS_ERR(plane)) {
317 			DRM_DEV_ERROR(dev->dev,
318 				"failed to construct plane for RGB%d\n", i + 1);
319 			ret = PTR_ERR(plane);
320 			goto fail;
321 		}
322 
323 		crtc  = mdp4_crtc_init(dev, plane, priv->num_crtcs, i,
324 				mdp4_crtcs[i]);
325 		if (IS_ERR(crtc)) {
326 			DRM_DEV_ERROR(dev->dev, "failed to construct crtc for %s\n",
327 				mdp4_crtc_names[i]);
328 			ret = PTR_ERR(crtc);
329 			goto fail;
330 		}
331 
332 		priv->num_crtcs++;
333 	}
334 
335 	/*
336 	 * we currently set up two relatively fixed paths:
337 	 *
338 	 * LCDC/LVDS path: RGB1 -> DMA_P -> LCDC -> LVDS
339 	 *			or
340 	 * DSI path: RGB1 -> DMA_P -> DSI1 -> DSI Panel
341 	 *
342 	 * DTV/HDMI path: RGB2 -> DMA_E -> DTV -> HDMI
343 	 */
344 
345 	for (i = 0; i < ARRAY_SIZE(mdp4_intfs); i++) {
346 		ret = mdp4_modeset_init_intf(mdp4_kms, mdp4_intfs[i]);
347 		if (ret) {
348 			DRM_DEV_ERROR(dev->dev, "failed to initialize intf: %d, %d\n",
349 				i, ret);
350 			goto fail;
351 		}
352 	}
353 
354 	return 0;
355 
356 fail:
357 	return ret;
358 }
359 
360 static void read_mdp_hw_revision(struct mdp4_kms *mdp4_kms,
361 				 u32 *major, u32 *minor)
362 {
363 	struct drm_device *dev = mdp4_kms->dev;
364 	u32 version;
365 
366 	mdp4_enable(mdp4_kms);
367 	version = mdp4_read(mdp4_kms, REG_MDP4_VERSION);
368 	mdp4_disable(mdp4_kms);
369 
370 	*major = FIELD(version, MDP4_VERSION_MAJOR);
371 	*minor = FIELD(version, MDP4_VERSION_MINOR);
372 
373 	DRM_DEV_INFO(dev->dev, "MDP4 version v%d.%d", *major, *minor);
374 }
375 
376 static int mdp4_kms_init(struct drm_device *dev)
377 {
378 	struct platform_device *pdev = to_platform_device(dev->dev);
379 	struct msm_drm_private *priv = dev->dev_private;
380 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(priv->kms));
381 	struct msm_kms *kms = NULL;
382 	struct msm_mmu *mmu;
383 	struct msm_gem_address_space *aspace;
384 	int ret;
385 	u32 major, minor;
386 	unsigned long max_clk;
387 
388 	/* TODO: Chips that aren't apq8064 have a 200 Mhz max_clk */
389 	max_clk = 266667000;
390 
391 	ret = mdp_kms_init(&mdp4_kms->base, &kms_funcs);
392 	if (ret) {
393 		DRM_DEV_ERROR(dev->dev, "failed to init kms\n");
394 		goto fail;
395 	}
396 
397 	kms = priv->kms;
398 
399 	mdp4_kms->dev = dev;
400 
401 	if (mdp4_kms->vdd) {
402 		ret = regulator_enable(mdp4_kms->vdd);
403 		if (ret) {
404 			DRM_DEV_ERROR(dev->dev, "failed to enable regulator vdd: %d\n", ret);
405 			goto fail;
406 		}
407 	}
408 
409 	clk_set_rate(mdp4_kms->clk, max_clk);
410 
411 	read_mdp_hw_revision(mdp4_kms, &major, &minor);
412 
413 	if (major != 4) {
414 		DRM_DEV_ERROR(dev->dev, "unexpected MDP version: v%d.%d\n",
415 			      major, minor);
416 		ret = -ENXIO;
417 		goto fail;
418 	}
419 
420 	mdp4_kms->rev = minor;
421 
422 	if (mdp4_kms->rev >= 2) {
423 		if (!mdp4_kms->lut_clk) {
424 			DRM_DEV_ERROR(dev->dev, "failed to get lut_clk\n");
425 			ret = -ENODEV;
426 			goto fail;
427 		}
428 		clk_set_rate(mdp4_kms->lut_clk, max_clk);
429 	}
430 
431 	pm_runtime_enable(dev->dev);
432 	mdp4_kms->rpm_enabled = true;
433 
434 	/* make sure things are off before attaching iommu (bootloader could
435 	 * have left things on, in which case we'll start getting faults if
436 	 * we don't disable):
437 	 */
438 	mdp4_enable(mdp4_kms);
439 	mdp4_write(mdp4_kms, REG_MDP4_DTV_ENABLE, 0);
440 	mdp4_write(mdp4_kms, REG_MDP4_LCDC_ENABLE, 0);
441 	mdp4_write(mdp4_kms, REG_MDP4_DSI_ENABLE, 0);
442 	mdp4_disable(mdp4_kms);
443 	mdelay(16);
444 
445 	mmu = msm_iommu_new(&pdev->dev, 0);
446 	if (IS_ERR(mmu)) {
447 		ret = PTR_ERR(mmu);
448 		goto fail;
449 	} else if (!mmu) {
450 		DRM_DEV_INFO(dev->dev, "no iommu, fallback to phys "
451 				"contig buffers for scanout\n");
452 		aspace = NULL;
453 	} else {
454 		aspace  = msm_gem_address_space_create(mmu,
455 			"mdp4", 0x1000, 0x100000000 - 0x1000);
456 
457 		if (IS_ERR(aspace)) {
458 			if (!IS_ERR(mmu))
459 				mmu->funcs->destroy(mmu);
460 			ret = PTR_ERR(aspace);
461 			goto fail;
462 		}
463 
464 		kms->aspace = aspace;
465 	}
466 
467 	ret = modeset_init(mdp4_kms);
468 	if (ret) {
469 		DRM_DEV_ERROR(dev->dev, "modeset_init failed: %d\n", ret);
470 		goto fail;
471 	}
472 
473 	mdp4_kms->blank_cursor_bo = msm_gem_new(dev, SZ_16K, MSM_BO_WC | MSM_BO_SCANOUT);
474 	if (IS_ERR(mdp4_kms->blank_cursor_bo)) {
475 		ret = PTR_ERR(mdp4_kms->blank_cursor_bo);
476 		DRM_DEV_ERROR(dev->dev, "could not allocate blank-cursor bo: %d\n", ret);
477 		mdp4_kms->blank_cursor_bo = NULL;
478 		goto fail;
479 	}
480 
481 	ret = msm_gem_get_and_pin_iova(mdp4_kms->blank_cursor_bo, kms->aspace,
482 			&mdp4_kms->blank_cursor_iova);
483 	if (ret) {
484 		DRM_DEV_ERROR(dev->dev, "could not pin blank-cursor bo: %d\n", ret);
485 		goto fail;
486 	}
487 
488 	dev->mode_config.min_width = 0;
489 	dev->mode_config.min_height = 0;
490 	dev->mode_config.max_width = 2048;
491 	dev->mode_config.max_height = 2048;
492 
493 	return 0;
494 
495 fail:
496 	if (kms)
497 		mdp4_destroy(kms);
498 
499 	return ret;
500 }
501 
502 static const struct dev_pm_ops mdp4_pm_ops = {
503 	.prepare = msm_kms_pm_prepare,
504 	.complete = msm_kms_pm_complete,
505 };
506 
507 static int mdp4_probe(struct platform_device *pdev)
508 {
509 	struct device *dev = &pdev->dev;
510 	struct mdp4_kms *mdp4_kms;
511 	int irq;
512 
513 	mdp4_kms = devm_kzalloc(dev, sizeof(*mdp4_kms), GFP_KERNEL);
514 	if (!mdp4_kms)
515 		return dev_err_probe(dev, -ENOMEM, "failed to allocate kms\n");
516 
517 	mdp4_kms->mmio = msm_ioremap(pdev, NULL);
518 	if (IS_ERR(mdp4_kms->mmio))
519 		return PTR_ERR(mdp4_kms->mmio);
520 
521 	irq = platform_get_irq(pdev, 0);
522 	if (irq < 0)
523 		return dev_err_probe(dev, irq, "failed to get irq\n");
524 
525 	mdp4_kms->base.base.irq = irq;
526 
527 	/* NOTE: driver for this regulator still missing upstream.. use
528 	 * _get_exclusive() and ignore the error if it does not exist
529 	 * (and hope that the bootloader left it on for us)
530 	 */
531 	mdp4_kms->vdd = devm_regulator_get_exclusive(&pdev->dev, "vdd");
532 	if (IS_ERR(mdp4_kms->vdd))
533 		mdp4_kms->vdd = NULL;
534 
535 	mdp4_kms->clk = devm_clk_get(&pdev->dev, "core_clk");
536 	if (IS_ERR(mdp4_kms->clk))
537 		return dev_err_probe(dev, PTR_ERR(mdp4_kms->clk), "failed to get core_clk\n");
538 
539 	mdp4_kms->pclk = devm_clk_get(&pdev->dev, "iface_clk");
540 	if (IS_ERR(mdp4_kms->pclk))
541 		mdp4_kms->pclk = NULL;
542 
543 	mdp4_kms->axi_clk = devm_clk_get(&pdev->dev, "bus_clk");
544 	if (IS_ERR(mdp4_kms->axi_clk))
545 		return dev_err_probe(dev, PTR_ERR(mdp4_kms->axi_clk), "failed to get axi_clk\n");
546 
547 	/*
548 	 * This is required for revn >= 2. Handle errors here and let the kms
549 	 * init bail out if the clock is not provided.
550 	 */
551 	mdp4_kms->lut_clk = devm_clk_get_optional(&pdev->dev, "lut_clk");
552 	if (IS_ERR(mdp4_kms->lut_clk))
553 		return dev_err_probe(dev, PTR_ERR(mdp4_kms->lut_clk), "failed to get lut_clk\n");
554 
555 	return msm_drv_probe(&pdev->dev, mdp4_kms_init, &mdp4_kms->base.base);
556 }
557 
558 static void mdp4_remove(struct platform_device *pdev)
559 {
560 	component_master_del(&pdev->dev, &msm_drm_ops);
561 }
562 
563 static const struct of_device_id mdp4_dt_match[] = {
564 	{ .compatible = "qcom,mdp4" },
565 	{ /* sentinel */ }
566 };
567 MODULE_DEVICE_TABLE(of, mdp4_dt_match);
568 
569 static struct platform_driver mdp4_platform_driver = {
570 	.probe      = mdp4_probe,
571 	.remove_new = mdp4_remove,
572 	.shutdown   = msm_kms_shutdown,
573 	.driver     = {
574 		.name   = "mdp4",
575 		.of_match_table = mdp4_dt_match,
576 		.pm     = &mdp4_pm_ops,
577 	},
578 };
579 
580 void __init msm_mdp4_register(void)
581 {
582 	platform_driver_register(&mdp4_platform_driver);
583 }
584 
585 void __exit msm_mdp4_unregister(void)
586 {
587 	platform_driver_unregister(&mdp4_platform_driver);
588 }
589