xref: /linux/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c (revision ab1c247094e323177a578b38f0325bf79f0317ac)
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 		.get_format      = mdp_get_format,
155 		.round_pixclk    = mdp4_round_pixclk,
156 		.destroy         = mdp4_destroy,
157 	},
158 	.set_irqmask         = mdp4_set_irqmask,
159 };
160 
161 int mdp4_disable(struct mdp4_kms *mdp4_kms)
162 {
163 	DBG("");
164 
165 	clk_disable_unprepare(mdp4_kms->clk);
166 	clk_disable_unprepare(mdp4_kms->pclk);
167 	clk_disable_unprepare(mdp4_kms->lut_clk);
168 	clk_disable_unprepare(mdp4_kms->axi_clk);
169 
170 	return 0;
171 }
172 
173 int mdp4_enable(struct mdp4_kms *mdp4_kms)
174 {
175 	DBG("");
176 
177 	clk_prepare_enable(mdp4_kms->clk);
178 	clk_prepare_enable(mdp4_kms->pclk);
179 	clk_prepare_enable(mdp4_kms->lut_clk);
180 	clk_prepare_enable(mdp4_kms->axi_clk);
181 
182 	return 0;
183 }
184 
185 
186 static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
187 				  int intf_type)
188 {
189 	struct drm_device *dev = mdp4_kms->dev;
190 	struct msm_drm_private *priv = dev->dev_private;
191 	struct drm_encoder *encoder;
192 	struct drm_connector *connector;
193 	struct device_node *panel_node;
194 	int dsi_id;
195 	int ret;
196 
197 	switch (intf_type) {
198 	case DRM_MODE_ENCODER_LVDS:
199 		/*
200 		 * bail out early if there is no panel node (no need to
201 		 * initialize LCDC encoder and LVDS connector)
202 		 */
203 		panel_node = of_graph_get_remote_node(dev->dev->of_node, 0, 0);
204 		if (!panel_node)
205 			return 0;
206 
207 		encoder = mdp4_lcdc_encoder_init(dev, panel_node);
208 		if (IS_ERR(encoder)) {
209 			DRM_DEV_ERROR(dev->dev, "failed to construct LCDC encoder\n");
210 			of_node_put(panel_node);
211 			return PTR_ERR(encoder);
212 		}
213 
214 		/* LCDC can be hooked to DMA_P (TODO: Add DMA_S later?) */
215 		encoder->possible_crtcs = 1 << DMA_P;
216 
217 		connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
218 		if (IS_ERR(connector)) {
219 			DRM_DEV_ERROR(dev->dev, "failed to initialize LVDS connector\n");
220 			of_node_put(panel_node);
221 			return PTR_ERR(connector);
222 		}
223 
224 		break;
225 	case DRM_MODE_ENCODER_TMDS:
226 		encoder = mdp4_dtv_encoder_init(dev);
227 		if (IS_ERR(encoder)) {
228 			DRM_DEV_ERROR(dev->dev, "failed to construct DTV encoder\n");
229 			return PTR_ERR(encoder);
230 		}
231 
232 		/* DTV can be hooked to DMA_E: */
233 		encoder->possible_crtcs = 1 << 1;
234 
235 		if (priv->hdmi) {
236 			/* Construct bridge/connector for HDMI: */
237 			ret = msm_hdmi_modeset_init(priv->hdmi, dev, encoder);
238 			if (ret) {
239 				DRM_DEV_ERROR(dev->dev, "failed to initialize HDMI: %d\n", ret);
240 				return ret;
241 			}
242 		}
243 
244 		break;
245 	case DRM_MODE_ENCODER_DSI:
246 		/* only DSI1 supported for now */
247 		dsi_id = 0;
248 
249 		if (!priv->dsi[dsi_id])
250 			break;
251 
252 		encoder = mdp4_dsi_encoder_init(dev);
253 		if (IS_ERR(encoder)) {
254 			ret = PTR_ERR(encoder);
255 			DRM_DEV_ERROR(dev->dev,
256 				"failed to construct DSI encoder: %d\n", ret);
257 			return ret;
258 		}
259 
260 		/* TODO: Add DMA_S later? */
261 		encoder->possible_crtcs = 1 << DMA_P;
262 
263 		ret = msm_dsi_modeset_init(priv->dsi[dsi_id], dev, encoder);
264 		if (ret) {
265 			DRM_DEV_ERROR(dev->dev, "failed to initialize DSI: %d\n",
266 				ret);
267 			return ret;
268 		}
269 
270 		break;
271 	default:
272 		DRM_DEV_ERROR(dev->dev, "Invalid or unsupported interface\n");
273 		return -EINVAL;
274 	}
275 
276 	return 0;
277 }
278 
279 static int modeset_init(struct mdp4_kms *mdp4_kms)
280 {
281 	struct drm_device *dev = mdp4_kms->dev;
282 	struct msm_drm_private *priv = dev->dev_private;
283 	struct drm_plane *plane;
284 	struct drm_crtc *crtc;
285 	int i, ret;
286 	static const enum mdp4_pipe rgb_planes[] = {
287 		RGB1, RGB2,
288 	};
289 	static const enum mdp4_pipe vg_planes[] = {
290 		VG1, VG2,
291 	};
292 	static const enum mdp4_dma mdp4_crtcs[] = {
293 		DMA_P, DMA_E,
294 	};
295 	static const char * const mdp4_crtc_names[] = {
296 		"DMA_P", "DMA_E",
297 	};
298 	static const int mdp4_intfs[] = {
299 		DRM_MODE_ENCODER_LVDS,
300 		DRM_MODE_ENCODER_DSI,
301 		DRM_MODE_ENCODER_TMDS,
302 	};
303 
304 	/* construct non-private planes: */
305 	for (i = 0; i < ARRAY_SIZE(vg_planes); i++) {
306 		plane = mdp4_plane_init(dev, vg_planes[i], false);
307 		if (IS_ERR(plane)) {
308 			DRM_DEV_ERROR(dev->dev,
309 				"failed to construct plane for VG%d\n", i + 1);
310 			ret = PTR_ERR(plane);
311 			goto fail;
312 		}
313 	}
314 
315 	for (i = 0; i < ARRAY_SIZE(mdp4_crtcs); i++) {
316 		plane = mdp4_plane_init(dev, rgb_planes[i], true);
317 		if (IS_ERR(plane)) {
318 			DRM_DEV_ERROR(dev->dev,
319 				"failed to construct plane for RGB%d\n", i + 1);
320 			ret = PTR_ERR(plane);
321 			goto fail;
322 		}
323 
324 		crtc  = mdp4_crtc_init(dev, plane, priv->num_crtcs, i,
325 				mdp4_crtcs[i]);
326 		if (IS_ERR(crtc)) {
327 			DRM_DEV_ERROR(dev->dev, "failed to construct crtc for %s\n",
328 				mdp4_crtc_names[i]);
329 			ret = PTR_ERR(crtc);
330 			goto fail;
331 		}
332 
333 		priv->num_crtcs++;
334 	}
335 
336 	/*
337 	 * we currently set up two relatively fixed paths:
338 	 *
339 	 * LCDC/LVDS path: RGB1 -> DMA_P -> LCDC -> LVDS
340 	 *			or
341 	 * DSI path: RGB1 -> DMA_P -> DSI1 -> DSI Panel
342 	 *
343 	 * DTV/HDMI path: RGB2 -> DMA_E -> DTV -> HDMI
344 	 */
345 
346 	for (i = 0; i < ARRAY_SIZE(mdp4_intfs); i++) {
347 		ret = mdp4_modeset_init_intf(mdp4_kms, mdp4_intfs[i]);
348 		if (ret) {
349 			DRM_DEV_ERROR(dev->dev, "failed to initialize intf: %d, %d\n",
350 				i, ret);
351 			goto fail;
352 		}
353 	}
354 
355 	return 0;
356 
357 fail:
358 	return ret;
359 }
360 
361 static void read_mdp_hw_revision(struct mdp4_kms *mdp4_kms,
362 				 u32 *major, u32 *minor)
363 {
364 	struct drm_device *dev = mdp4_kms->dev;
365 	u32 version;
366 
367 	mdp4_enable(mdp4_kms);
368 	version = mdp4_read(mdp4_kms, REG_MDP4_VERSION);
369 	mdp4_disable(mdp4_kms);
370 
371 	*major = FIELD(version, MDP4_VERSION_MAJOR);
372 	*minor = FIELD(version, MDP4_VERSION_MINOR);
373 
374 	DRM_DEV_INFO(dev->dev, "MDP4 version v%d.%d", *major, *minor);
375 }
376 
377 static int mdp4_kms_init(struct drm_device *dev)
378 {
379 	struct platform_device *pdev = to_platform_device(dev->dev);
380 	struct msm_drm_private *priv = dev->dev_private;
381 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(priv->kms));
382 	struct msm_kms *kms = NULL;
383 	struct msm_mmu *mmu;
384 	struct msm_gem_address_space *aspace;
385 	int ret;
386 	u32 major, minor;
387 	unsigned long max_clk;
388 
389 	/* TODO: Chips that aren't apq8064 have a 200 Mhz max_clk */
390 	max_clk = 266667000;
391 
392 	ret = mdp_kms_init(&mdp4_kms->base, &kms_funcs);
393 	if (ret) {
394 		DRM_DEV_ERROR(dev->dev, "failed to init kms\n");
395 		goto fail;
396 	}
397 
398 	kms = priv->kms;
399 
400 	mdp4_kms->dev = dev;
401 
402 	if (mdp4_kms->vdd) {
403 		ret = regulator_enable(mdp4_kms->vdd);
404 		if (ret) {
405 			DRM_DEV_ERROR(dev->dev, "failed to enable regulator vdd: %d\n", ret);
406 			goto fail;
407 		}
408 	}
409 
410 	clk_set_rate(mdp4_kms->clk, max_clk);
411 
412 	read_mdp_hw_revision(mdp4_kms, &major, &minor);
413 
414 	if (major != 4) {
415 		DRM_DEV_ERROR(dev->dev, "unexpected MDP version: v%d.%d\n",
416 			      major, minor);
417 		ret = -ENXIO;
418 		goto fail;
419 	}
420 
421 	mdp4_kms->rev = minor;
422 
423 	if (mdp4_kms->rev >= 2) {
424 		if (!mdp4_kms->lut_clk) {
425 			DRM_DEV_ERROR(dev->dev, "failed to get lut_clk\n");
426 			ret = -ENODEV;
427 			goto fail;
428 		}
429 		clk_set_rate(mdp4_kms->lut_clk, max_clk);
430 	}
431 
432 	pm_runtime_enable(dev->dev);
433 	mdp4_kms->rpm_enabled = true;
434 
435 	/* make sure things are off before attaching iommu (bootloader could
436 	 * have left things on, in which case we'll start getting faults if
437 	 * we don't disable):
438 	 */
439 	mdp4_enable(mdp4_kms);
440 	mdp4_write(mdp4_kms, REG_MDP4_DTV_ENABLE, 0);
441 	mdp4_write(mdp4_kms, REG_MDP4_LCDC_ENABLE, 0);
442 	mdp4_write(mdp4_kms, REG_MDP4_DSI_ENABLE, 0);
443 	mdp4_disable(mdp4_kms);
444 	mdelay(16);
445 
446 	mmu = msm_iommu_new(&pdev->dev, 0);
447 	if (IS_ERR(mmu)) {
448 		ret = PTR_ERR(mmu);
449 		goto fail;
450 	} else if (!mmu) {
451 		DRM_DEV_INFO(dev->dev, "no iommu, fallback to phys "
452 				"contig buffers for scanout\n");
453 		aspace = NULL;
454 	} else {
455 		aspace  = msm_gem_address_space_create(mmu,
456 			"mdp4", 0x1000, 0x100000000 - 0x1000);
457 
458 		if (IS_ERR(aspace)) {
459 			if (!IS_ERR(mmu))
460 				mmu->funcs->destroy(mmu);
461 			ret = PTR_ERR(aspace);
462 			goto fail;
463 		}
464 
465 		kms->aspace = aspace;
466 	}
467 
468 	ret = modeset_init(mdp4_kms);
469 	if (ret) {
470 		DRM_DEV_ERROR(dev->dev, "modeset_init failed: %d\n", ret);
471 		goto fail;
472 	}
473 
474 	mdp4_kms->blank_cursor_bo = msm_gem_new(dev, SZ_16K, MSM_BO_WC | MSM_BO_SCANOUT);
475 	if (IS_ERR(mdp4_kms->blank_cursor_bo)) {
476 		ret = PTR_ERR(mdp4_kms->blank_cursor_bo);
477 		DRM_DEV_ERROR(dev->dev, "could not allocate blank-cursor bo: %d\n", ret);
478 		mdp4_kms->blank_cursor_bo = NULL;
479 		goto fail;
480 	}
481 
482 	ret = msm_gem_get_and_pin_iova(mdp4_kms->blank_cursor_bo, kms->aspace,
483 			&mdp4_kms->blank_cursor_iova);
484 	if (ret) {
485 		DRM_DEV_ERROR(dev->dev, "could not pin blank-cursor bo: %d\n", ret);
486 		goto fail;
487 	}
488 
489 	dev->mode_config.min_width = 0;
490 	dev->mode_config.min_height = 0;
491 	dev->mode_config.max_width = 2048;
492 	dev->mode_config.max_height = 2048;
493 
494 	return 0;
495 
496 fail:
497 	if (kms)
498 		mdp4_destroy(kms);
499 
500 	return ret;
501 }
502 
503 static const struct dev_pm_ops mdp4_pm_ops = {
504 	.prepare = msm_kms_pm_prepare,
505 	.complete = msm_kms_pm_complete,
506 };
507 
508 static int mdp4_probe(struct platform_device *pdev)
509 {
510 	struct device *dev = &pdev->dev;
511 	struct mdp4_kms *mdp4_kms;
512 	int irq;
513 
514 	mdp4_kms = devm_kzalloc(dev, sizeof(*mdp4_kms), GFP_KERNEL);
515 	if (!mdp4_kms)
516 		return dev_err_probe(dev, -ENOMEM, "failed to allocate kms\n");
517 
518 	mdp4_kms->mmio = msm_ioremap(pdev, NULL);
519 	if (IS_ERR(mdp4_kms->mmio))
520 		return PTR_ERR(mdp4_kms->mmio);
521 
522 	irq = platform_get_irq(pdev, 0);
523 	if (irq < 0)
524 		return dev_err_probe(dev, irq, "failed to get irq\n");
525 
526 	mdp4_kms->base.base.irq = irq;
527 
528 	/* NOTE: driver for this regulator still missing upstream.. use
529 	 * _get_exclusive() and ignore the error if it does not exist
530 	 * (and hope that the bootloader left it on for us)
531 	 */
532 	mdp4_kms->vdd = devm_regulator_get_exclusive(&pdev->dev, "vdd");
533 	if (IS_ERR(mdp4_kms->vdd))
534 		mdp4_kms->vdd = NULL;
535 
536 	mdp4_kms->clk = devm_clk_get(&pdev->dev, "core_clk");
537 	if (IS_ERR(mdp4_kms->clk))
538 		return dev_err_probe(dev, PTR_ERR(mdp4_kms->clk), "failed to get core_clk\n");
539 
540 	mdp4_kms->pclk = devm_clk_get(&pdev->dev, "iface_clk");
541 	if (IS_ERR(mdp4_kms->pclk))
542 		mdp4_kms->pclk = NULL;
543 
544 	mdp4_kms->axi_clk = devm_clk_get(&pdev->dev, "bus_clk");
545 	if (IS_ERR(mdp4_kms->axi_clk))
546 		return dev_err_probe(dev, PTR_ERR(mdp4_kms->axi_clk), "failed to get axi_clk\n");
547 
548 	/*
549 	 * This is required for revn >= 2. Handle errors here and let the kms
550 	 * init bail out if the clock is not provided.
551 	 */
552 	mdp4_kms->lut_clk = devm_clk_get_optional(&pdev->dev, "lut_clk");
553 	if (IS_ERR(mdp4_kms->lut_clk))
554 		return dev_err_probe(dev, PTR_ERR(mdp4_kms->lut_clk), "failed to get lut_clk\n");
555 
556 	return msm_drv_probe(&pdev->dev, mdp4_kms_init, &mdp4_kms->base.base);
557 }
558 
559 static void mdp4_remove(struct platform_device *pdev)
560 {
561 	component_master_del(&pdev->dev, &msm_drm_ops);
562 }
563 
564 static const struct of_device_id mdp4_dt_match[] = {
565 	{ .compatible = "qcom,mdp4" },
566 	{ /* sentinel */ }
567 };
568 MODULE_DEVICE_TABLE(of, mdp4_dt_match);
569 
570 static struct platform_driver mdp4_platform_driver = {
571 	.probe      = mdp4_probe,
572 	.remove_new = mdp4_remove,
573 	.shutdown   = msm_kms_shutdown,
574 	.driver     = {
575 		.name   = "mdp4",
576 		.of_match_table = mdp4_dt_match,
577 		.pm     = &mdp4_pm_ops,
578 	},
579 };
580 
581 void __init msm_mdp4_register(void)
582 {
583 	platform_driver_register(&mdp4_platform_driver);
584 }
585 
586 void __exit msm_mdp4_unregister(void)
587 {
588 	platform_driver_unregister(&mdp4_platform_driver);
589 }
590