xref: /openbmc/linux/drivers/gpu/drm/tegra/drm.c (revision 77d84ff8)
1 /*
2  * Copyright (C) 2012 Avionic Design GmbH
3  * Copyright (C) 2012-2013 NVIDIA CORPORATION.  All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <linux/host1x.h>
11 
12 #include "drm.h"
13 #include "gem.h"
14 
15 #define DRIVER_NAME "tegra"
16 #define DRIVER_DESC "NVIDIA Tegra graphics"
17 #define DRIVER_DATE "20120330"
18 #define DRIVER_MAJOR 0
19 #define DRIVER_MINOR 0
20 #define DRIVER_PATCHLEVEL 0
21 
22 struct tegra_drm_file {
23 	struct list_head contexts;
24 };
25 
26 static int tegra_drm_load(struct drm_device *drm, unsigned long flags)
27 {
28 	struct host1x_device *device = to_host1x_device(drm->dev);
29 	struct tegra_drm *tegra;
30 	int err;
31 
32 	tegra = kzalloc(sizeof(*tegra), GFP_KERNEL);
33 	if (!tegra)
34 		return -ENOMEM;
35 
36 	dev_set_drvdata(drm->dev, tegra);
37 	mutex_init(&tegra->clients_lock);
38 	INIT_LIST_HEAD(&tegra->clients);
39 	drm->dev_private = tegra;
40 	tegra->drm = drm;
41 
42 	drm_mode_config_init(drm);
43 
44 	err = host1x_device_init(device);
45 	if (err < 0)
46 		return err;
47 
48 	/*
49 	 * We don't use the drm_irq_install() helpers provided by the DRM
50 	 * core, so we need to set this manually in order to allow the
51 	 * DRM_IOCTL_WAIT_VBLANK to operate correctly.
52 	 */
53 	drm->irq_enabled = true;
54 
55 	err = drm_vblank_init(drm, drm->mode_config.num_crtc);
56 	if (err < 0)
57 		return err;
58 
59 	err = tegra_drm_fb_init(drm);
60 	if (err < 0)
61 		return err;
62 
63 	drm_kms_helper_poll_init(drm);
64 
65 	return 0;
66 }
67 
68 static int tegra_drm_unload(struct drm_device *drm)
69 {
70 	struct host1x_device *device = to_host1x_device(drm->dev);
71 	int err;
72 
73 	drm_kms_helper_poll_fini(drm);
74 	tegra_drm_fb_exit(drm);
75 	drm_vblank_cleanup(drm);
76 	drm_mode_config_cleanup(drm);
77 
78 	err = host1x_device_exit(device);
79 	if (err < 0)
80 		return err;
81 
82 	return 0;
83 }
84 
85 static int tegra_drm_open(struct drm_device *drm, struct drm_file *filp)
86 {
87 	struct tegra_drm_file *fpriv;
88 
89 	fpriv = kzalloc(sizeof(*fpriv), GFP_KERNEL);
90 	if (!fpriv)
91 		return -ENOMEM;
92 
93 	INIT_LIST_HEAD(&fpriv->contexts);
94 	filp->driver_priv = fpriv;
95 
96 	return 0;
97 }
98 
99 static void tegra_drm_context_free(struct tegra_drm_context *context)
100 {
101 	context->client->ops->close_channel(context);
102 	kfree(context);
103 }
104 
105 static void tegra_drm_lastclose(struct drm_device *drm)
106 {
107 	struct tegra_drm *tegra = drm->dev_private;
108 
109 	tegra_fbdev_restore_mode(tegra->fbdev);
110 }
111 
112 static struct host1x_bo *
113 host1x_bo_lookup(struct drm_device *drm, struct drm_file *file, u32 handle)
114 {
115 	struct drm_gem_object *gem;
116 	struct tegra_bo *bo;
117 
118 	gem = drm_gem_object_lookup(drm, file, handle);
119 	if (!gem)
120 		return NULL;
121 
122 	mutex_lock(&drm->struct_mutex);
123 	drm_gem_object_unreference(gem);
124 	mutex_unlock(&drm->struct_mutex);
125 
126 	bo = to_tegra_bo(gem);
127 	return &bo->base;
128 }
129 
130 int tegra_drm_submit(struct tegra_drm_context *context,
131 		     struct drm_tegra_submit *args, struct drm_device *drm,
132 		     struct drm_file *file)
133 {
134 	unsigned int num_cmdbufs = args->num_cmdbufs;
135 	unsigned int num_relocs = args->num_relocs;
136 	unsigned int num_waitchks = args->num_waitchks;
137 	struct drm_tegra_cmdbuf __user *cmdbufs =
138 		(void __user *)(uintptr_t)args->cmdbufs;
139 	struct drm_tegra_reloc __user *relocs =
140 		(void __user *)(uintptr_t)args->relocs;
141 	struct drm_tegra_waitchk __user *waitchks =
142 		(void __user *)(uintptr_t)args->waitchks;
143 	struct drm_tegra_syncpt syncpt;
144 	struct host1x_job *job;
145 	int err;
146 
147 	/* We don't yet support other than one syncpt_incr struct per submit */
148 	if (args->num_syncpts != 1)
149 		return -EINVAL;
150 
151 	job = host1x_job_alloc(context->channel, args->num_cmdbufs,
152 			       args->num_relocs, args->num_waitchks);
153 	if (!job)
154 		return -ENOMEM;
155 
156 	job->num_relocs = args->num_relocs;
157 	job->num_waitchk = args->num_waitchks;
158 	job->client = (u32)args->context;
159 	job->class = context->client->base.class;
160 	job->serialize = true;
161 
162 	while (num_cmdbufs) {
163 		struct drm_tegra_cmdbuf cmdbuf;
164 		struct host1x_bo *bo;
165 
166 		if (copy_from_user(&cmdbuf, cmdbufs, sizeof(cmdbuf))) {
167 			err = -EFAULT;
168 			goto fail;
169 		}
170 
171 		bo = host1x_bo_lookup(drm, file, cmdbuf.handle);
172 		if (!bo) {
173 			err = -ENOENT;
174 			goto fail;
175 		}
176 
177 		host1x_job_add_gather(job, bo, cmdbuf.words, cmdbuf.offset);
178 		num_cmdbufs--;
179 		cmdbufs++;
180 	}
181 
182 	if (copy_from_user(job->relocarray, relocs,
183 			   sizeof(*relocs) * num_relocs)) {
184 		err = -EFAULT;
185 		goto fail;
186 	}
187 
188 	while (num_relocs--) {
189 		struct host1x_reloc *reloc = &job->relocarray[num_relocs];
190 		struct host1x_bo *cmdbuf, *target;
191 
192 		cmdbuf = host1x_bo_lookup(drm, file, (u32)reloc->cmdbuf);
193 		target = host1x_bo_lookup(drm, file, (u32)reloc->target);
194 
195 		reloc->cmdbuf = cmdbuf;
196 		reloc->target = target;
197 
198 		if (!reloc->target || !reloc->cmdbuf) {
199 			err = -ENOENT;
200 			goto fail;
201 		}
202 	}
203 
204 	if (copy_from_user(job->waitchk, waitchks,
205 			   sizeof(*waitchks) * num_waitchks)) {
206 		err = -EFAULT;
207 		goto fail;
208 	}
209 
210 	if (copy_from_user(&syncpt, (void __user *)(uintptr_t)args->syncpts,
211 			   sizeof(syncpt))) {
212 		err = -EFAULT;
213 		goto fail;
214 	}
215 
216 	job->is_addr_reg = context->client->ops->is_addr_reg;
217 	job->syncpt_incrs = syncpt.incrs;
218 	job->syncpt_id = syncpt.id;
219 	job->timeout = 10000;
220 
221 	if (args->timeout && args->timeout < 10000)
222 		job->timeout = args->timeout;
223 
224 	err = host1x_job_pin(job, context->client->base.dev);
225 	if (err)
226 		goto fail;
227 
228 	err = host1x_job_submit(job);
229 	if (err)
230 		goto fail_submit;
231 
232 	args->fence = job->syncpt_end;
233 
234 	host1x_job_put(job);
235 	return 0;
236 
237 fail_submit:
238 	host1x_job_unpin(job);
239 fail:
240 	host1x_job_put(job);
241 	return err;
242 }
243 
244 
245 #ifdef CONFIG_DRM_TEGRA_STAGING
246 static struct tegra_drm_context *tegra_drm_get_context(__u64 context)
247 {
248 	return (struct tegra_drm_context *)(uintptr_t)context;
249 }
250 
251 static bool tegra_drm_file_owns_context(struct tegra_drm_file *file,
252 					struct tegra_drm_context *context)
253 {
254 	struct tegra_drm_context *ctx;
255 
256 	list_for_each_entry(ctx, &file->contexts, list)
257 		if (ctx == context)
258 			return true;
259 
260 	return false;
261 }
262 
263 static int tegra_gem_create(struct drm_device *drm, void *data,
264 			    struct drm_file *file)
265 {
266 	struct drm_tegra_gem_create *args = data;
267 	struct tegra_bo *bo;
268 
269 	bo = tegra_bo_create_with_handle(file, drm, args->size, args->flags,
270 					 &args->handle);
271 	if (IS_ERR(bo))
272 		return PTR_ERR(bo);
273 
274 	return 0;
275 }
276 
277 static int tegra_gem_mmap(struct drm_device *drm, void *data,
278 			  struct drm_file *file)
279 {
280 	struct drm_tegra_gem_mmap *args = data;
281 	struct drm_gem_object *gem;
282 	struct tegra_bo *bo;
283 
284 	gem = drm_gem_object_lookup(drm, file, args->handle);
285 	if (!gem)
286 		return -EINVAL;
287 
288 	bo = to_tegra_bo(gem);
289 
290 	args->offset = drm_vma_node_offset_addr(&bo->gem.vma_node);
291 
292 	drm_gem_object_unreference(gem);
293 
294 	return 0;
295 }
296 
297 static int tegra_syncpt_read(struct drm_device *drm, void *data,
298 			     struct drm_file *file)
299 {
300 	struct host1x *host = dev_get_drvdata(drm->dev->parent);
301 	struct drm_tegra_syncpt_read *args = data;
302 	struct host1x_syncpt *sp;
303 
304 	sp = host1x_syncpt_get(host, args->id);
305 	if (!sp)
306 		return -EINVAL;
307 
308 	args->value = host1x_syncpt_read_min(sp);
309 	return 0;
310 }
311 
312 static int tegra_syncpt_incr(struct drm_device *drm, void *data,
313 			     struct drm_file *file)
314 {
315 	struct host1x *host1x = dev_get_drvdata(drm->dev->parent);
316 	struct drm_tegra_syncpt_incr *args = data;
317 	struct host1x_syncpt *sp;
318 
319 	sp = host1x_syncpt_get(host1x, args->id);
320 	if (!sp)
321 		return -EINVAL;
322 
323 	return host1x_syncpt_incr(sp);
324 }
325 
326 static int tegra_syncpt_wait(struct drm_device *drm, void *data,
327 			     struct drm_file *file)
328 {
329 	struct host1x *host1x = dev_get_drvdata(drm->dev->parent);
330 	struct drm_tegra_syncpt_wait *args = data;
331 	struct host1x_syncpt *sp;
332 
333 	sp = host1x_syncpt_get(host1x, args->id);
334 	if (!sp)
335 		return -EINVAL;
336 
337 	return host1x_syncpt_wait(sp, args->thresh, args->timeout,
338 				  &args->value);
339 }
340 
341 static int tegra_open_channel(struct drm_device *drm, void *data,
342 			      struct drm_file *file)
343 {
344 	struct tegra_drm_file *fpriv = file->driver_priv;
345 	struct tegra_drm *tegra = drm->dev_private;
346 	struct drm_tegra_open_channel *args = data;
347 	struct tegra_drm_context *context;
348 	struct tegra_drm_client *client;
349 	int err = -ENODEV;
350 
351 	context = kzalloc(sizeof(*context), GFP_KERNEL);
352 	if (!context)
353 		return -ENOMEM;
354 
355 	list_for_each_entry(client, &tegra->clients, list)
356 		if (client->base.class == args->client) {
357 			err = client->ops->open_channel(client, context);
358 			if (err)
359 				break;
360 
361 			list_add(&context->list, &fpriv->contexts);
362 			args->context = (uintptr_t)context;
363 			context->client = client;
364 			return 0;
365 		}
366 
367 	kfree(context);
368 	return err;
369 }
370 
371 static int tegra_close_channel(struct drm_device *drm, void *data,
372 			       struct drm_file *file)
373 {
374 	struct tegra_drm_file *fpriv = file->driver_priv;
375 	struct drm_tegra_close_channel *args = data;
376 	struct tegra_drm_context *context;
377 
378 	context = tegra_drm_get_context(args->context);
379 
380 	if (!tegra_drm_file_owns_context(fpriv, context))
381 		return -EINVAL;
382 
383 	list_del(&context->list);
384 	tegra_drm_context_free(context);
385 
386 	return 0;
387 }
388 
389 static int tegra_get_syncpt(struct drm_device *drm, void *data,
390 			    struct drm_file *file)
391 {
392 	struct tegra_drm_file *fpriv = file->driver_priv;
393 	struct drm_tegra_get_syncpt *args = data;
394 	struct tegra_drm_context *context;
395 	struct host1x_syncpt *syncpt;
396 
397 	context = tegra_drm_get_context(args->context);
398 
399 	if (!tegra_drm_file_owns_context(fpriv, context))
400 		return -ENODEV;
401 
402 	if (args->index >= context->client->base.num_syncpts)
403 		return -EINVAL;
404 
405 	syncpt = context->client->base.syncpts[args->index];
406 	args->id = host1x_syncpt_id(syncpt);
407 
408 	return 0;
409 }
410 
411 static int tegra_submit(struct drm_device *drm, void *data,
412 			struct drm_file *file)
413 {
414 	struct tegra_drm_file *fpriv = file->driver_priv;
415 	struct drm_tegra_submit *args = data;
416 	struct tegra_drm_context *context;
417 
418 	context = tegra_drm_get_context(args->context);
419 
420 	if (!tegra_drm_file_owns_context(fpriv, context))
421 		return -ENODEV;
422 
423 	return context->client->ops->submit(context, args, drm, file);
424 }
425 
426 static int tegra_get_syncpt_base(struct drm_device *drm, void *data,
427 				 struct drm_file *file)
428 {
429 	struct tegra_drm_file *fpriv = file->driver_priv;
430 	struct drm_tegra_get_syncpt_base *args = data;
431 	struct tegra_drm_context *context;
432 	struct host1x_syncpt_base *base;
433 	struct host1x_syncpt *syncpt;
434 
435 	context = tegra_drm_get_context(args->context);
436 
437 	if (!tegra_drm_file_owns_context(fpriv, context))
438 		return -ENODEV;
439 
440 	if (args->syncpt >= context->client->base.num_syncpts)
441 		return -EINVAL;
442 
443 	syncpt = context->client->base.syncpts[args->syncpt];
444 
445 	base = host1x_syncpt_get_base(syncpt);
446 	if (!base)
447 		return -ENXIO;
448 
449 	args->id = host1x_syncpt_base_id(base);
450 
451 	return 0;
452 }
453 #endif
454 
455 static const struct drm_ioctl_desc tegra_drm_ioctls[] = {
456 #ifdef CONFIG_DRM_TEGRA_STAGING
457 	DRM_IOCTL_DEF_DRV(TEGRA_GEM_CREATE, tegra_gem_create, DRM_UNLOCKED | DRM_AUTH),
458 	DRM_IOCTL_DEF_DRV(TEGRA_GEM_MMAP, tegra_gem_mmap, DRM_UNLOCKED),
459 	DRM_IOCTL_DEF_DRV(TEGRA_SYNCPT_READ, tegra_syncpt_read, DRM_UNLOCKED),
460 	DRM_IOCTL_DEF_DRV(TEGRA_SYNCPT_INCR, tegra_syncpt_incr, DRM_UNLOCKED),
461 	DRM_IOCTL_DEF_DRV(TEGRA_SYNCPT_WAIT, tegra_syncpt_wait, DRM_UNLOCKED),
462 	DRM_IOCTL_DEF_DRV(TEGRA_OPEN_CHANNEL, tegra_open_channel, DRM_UNLOCKED),
463 	DRM_IOCTL_DEF_DRV(TEGRA_CLOSE_CHANNEL, tegra_close_channel, DRM_UNLOCKED),
464 	DRM_IOCTL_DEF_DRV(TEGRA_GET_SYNCPT, tegra_get_syncpt, DRM_UNLOCKED),
465 	DRM_IOCTL_DEF_DRV(TEGRA_SUBMIT, tegra_submit, DRM_UNLOCKED),
466 	DRM_IOCTL_DEF_DRV(TEGRA_GET_SYNCPT_BASE, tegra_get_syncpt_base, DRM_UNLOCKED),
467 #endif
468 };
469 
470 static const struct file_operations tegra_drm_fops = {
471 	.owner = THIS_MODULE,
472 	.open = drm_open,
473 	.release = drm_release,
474 	.unlocked_ioctl = drm_ioctl,
475 	.mmap = tegra_drm_mmap,
476 	.poll = drm_poll,
477 	.read = drm_read,
478 #ifdef CONFIG_COMPAT
479 	.compat_ioctl = drm_compat_ioctl,
480 #endif
481 	.llseek = noop_llseek,
482 };
483 
484 static struct drm_crtc *tegra_crtc_from_pipe(struct drm_device *drm, int pipe)
485 {
486 	struct drm_crtc *crtc;
487 
488 	list_for_each_entry(crtc, &drm->mode_config.crtc_list, head) {
489 		struct tegra_dc *dc = to_tegra_dc(crtc);
490 
491 		if (dc->pipe == pipe)
492 			return crtc;
493 	}
494 
495 	return NULL;
496 }
497 
498 static u32 tegra_drm_get_vblank_counter(struct drm_device *dev, int crtc)
499 {
500 	/* TODO: implement real hardware counter using syncpoints */
501 	return drm_vblank_count(dev, crtc);
502 }
503 
504 static int tegra_drm_enable_vblank(struct drm_device *drm, int pipe)
505 {
506 	struct drm_crtc *crtc = tegra_crtc_from_pipe(drm, pipe);
507 	struct tegra_dc *dc = to_tegra_dc(crtc);
508 
509 	if (!crtc)
510 		return -ENODEV;
511 
512 	tegra_dc_enable_vblank(dc);
513 
514 	return 0;
515 }
516 
517 static void tegra_drm_disable_vblank(struct drm_device *drm, int pipe)
518 {
519 	struct drm_crtc *crtc = tegra_crtc_from_pipe(drm, pipe);
520 	struct tegra_dc *dc = to_tegra_dc(crtc);
521 
522 	if (crtc)
523 		tegra_dc_disable_vblank(dc);
524 }
525 
526 static void tegra_drm_preclose(struct drm_device *drm, struct drm_file *file)
527 {
528 	struct tegra_drm_file *fpriv = file->driver_priv;
529 	struct tegra_drm_context *context, *tmp;
530 	struct drm_crtc *crtc;
531 
532 	list_for_each_entry(crtc, &drm->mode_config.crtc_list, head)
533 		tegra_dc_cancel_page_flip(crtc, file);
534 
535 	list_for_each_entry_safe(context, tmp, &fpriv->contexts, list)
536 		tegra_drm_context_free(context);
537 
538 	kfree(fpriv);
539 }
540 
541 #ifdef CONFIG_DEBUG_FS
542 static int tegra_debugfs_framebuffers(struct seq_file *s, void *data)
543 {
544 	struct drm_info_node *node = (struct drm_info_node *)s->private;
545 	struct drm_device *drm = node->minor->dev;
546 	struct drm_framebuffer *fb;
547 
548 	mutex_lock(&drm->mode_config.fb_lock);
549 
550 	list_for_each_entry(fb, &drm->mode_config.fb_list, head) {
551 		seq_printf(s, "%3d: user size: %d x %d, depth %d, %d bpp, refcount %d\n",
552 			   fb->base.id, fb->width, fb->height, fb->depth,
553 			   fb->bits_per_pixel,
554 			   atomic_read(&fb->refcount.refcount));
555 	}
556 
557 	mutex_unlock(&drm->mode_config.fb_lock);
558 
559 	return 0;
560 }
561 
562 static struct drm_info_list tegra_debugfs_list[] = {
563 	{ "framebuffers", tegra_debugfs_framebuffers, 0 },
564 };
565 
566 static int tegra_debugfs_init(struct drm_minor *minor)
567 {
568 	return drm_debugfs_create_files(tegra_debugfs_list,
569 					ARRAY_SIZE(tegra_debugfs_list),
570 					minor->debugfs_root, minor);
571 }
572 
573 static void tegra_debugfs_cleanup(struct drm_minor *minor)
574 {
575 	drm_debugfs_remove_files(tegra_debugfs_list,
576 				 ARRAY_SIZE(tegra_debugfs_list), minor);
577 }
578 #endif
579 
580 static struct drm_driver tegra_drm_driver = {
581 	.driver_features = DRIVER_MODESET | DRIVER_GEM,
582 	.load = tegra_drm_load,
583 	.unload = tegra_drm_unload,
584 	.open = tegra_drm_open,
585 	.preclose = tegra_drm_preclose,
586 	.lastclose = tegra_drm_lastclose,
587 
588 	.get_vblank_counter = tegra_drm_get_vblank_counter,
589 	.enable_vblank = tegra_drm_enable_vblank,
590 	.disable_vblank = tegra_drm_disable_vblank,
591 
592 #if defined(CONFIG_DEBUG_FS)
593 	.debugfs_init = tegra_debugfs_init,
594 	.debugfs_cleanup = tegra_debugfs_cleanup,
595 #endif
596 
597 	.gem_free_object = tegra_bo_free_object,
598 	.gem_vm_ops = &tegra_bo_vm_ops,
599 	.dumb_create = tegra_bo_dumb_create,
600 	.dumb_map_offset = tegra_bo_dumb_map_offset,
601 	.dumb_destroy = drm_gem_dumb_destroy,
602 
603 	.ioctls = tegra_drm_ioctls,
604 	.num_ioctls = ARRAY_SIZE(tegra_drm_ioctls),
605 	.fops = &tegra_drm_fops,
606 
607 	.name = DRIVER_NAME,
608 	.desc = DRIVER_DESC,
609 	.date = DRIVER_DATE,
610 	.major = DRIVER_MAJOR,
611 	.minor = DRIVER_MINOR,
612 	.patchlevel = DRIVER_PATCHLEVEL,
613 };
614 
615 int tegra_drm_register_client(struct tegra_drm *tegra,
616 			      struct tegra_drm_client *client)
617 {
618 	mutex_lock(&tegra->clients_lock);
619 	list_add_tail(&client->list, &tegra->clients);
620 	mutex_unlock(&tegra->clients_lock);
621 
622 	return 0;
623 }
624 
625 int tegra_drm_unregister_client(struct tegra_drm *tegra,
626 				struct tegra_drm_client *client)
627 {
628 	mutex_lock(&tegra->clients_lock);
629 	list_del_init(&client->list);
630 	mutex_unlock(&tegra->clients_lock);
631 
632 	return 0;
633 }
634 
635 static int host1x_drm_probe(struct host1x_device *device)
636 {
637 	return drm_host1x_init(&tegra_drm_driver, device);
638 }
639 
640 static int host1x_drm_remove(struct host1x_device *device)
641 {
642 	drm_host1x_exit(&tegra_drm_driver, device);
643 
644 	return 0;
645 }
646 
647 static const struct of_device_id host1x_drm_subdevs[] = {
648 	{ .compatible = "nvidia,tegra20-dc", },
649 	{ .compatible = "nvidia,tegra20-hdmi", },
650 	{ .compatible = "nvidia,tegra20-gr2d", },
651 	{ .compatible = "nvidia,tegra20-gr3d", },
652 	{ .compatible = "nvidia,tegra30-dc", },
653 	{ .compatible = "nvidia,tegra30-hdmi", },
654 	{ .compatible = "nvidia,tegra30-gr2d", },
655 	{ .compatible = "nvidia,tegra30-gr3d", },
656 	{ .compatible = "nvidia,tegra114-hdmi", },
657 	{ .compatible = "nvidia,tegra114-gr3d", },
658 	{ /* sentinel */ }
659 };
660 
661 static struct host1x_driver host1x_drm_driver = {
662 	.name = "drm",
663 	.probe = host1x_drm_probe,
664 	.remove = host1x_drm_remove,
665 	.subdevs = host1x_drm_subdevs,
666 };
667 
668 static int __init host1x_drm_init(void)
669 {
670 	int err;
671 
672 	err = host1x_driver_register(&host1x_drm_driver);
673 	if (err < 0)
674 		return err;
675 
676 	err = platform_driver_register(&tegra_dc_driver);
677 	if (err < 0)
678 		goto unregister_host1x;
679 
680 	err = platform_driver_register(&tegra_hdmi_driver);
681 	if (err < 0)
682 		goto unregister_dc;
683 
684 	err = platform_driver_register(&tegra_gr2d_driver);
685 	if (err < 0)
686 		goto unregister_hdmi;
687 
688 	err = platform_driver_register(&tegra_gr3d_driver);
689 	if (err < 0)
690 		goto unregister_gr2d;
691 
692 	return 0;
693 
694 unregister_gr2d:
695 	platform_driver_unregister(&tegra_gr2d_driver);
696 unregister_hdmi:
697 	platform_driver_unregister(&tegra_hdmi_driver);
698 unregister_dc:
699 	platform_driver_unregister(&tegra_dc_driver);
700 unregister_host1x:
701 	host1x_driver_unregister(&host1x_drm_driver);
702 	return err;
703 }
704 module_init(host1x_drm_init);
705 
706 static void __exit host1x_drm_exit(void)
707 {
708 	platform_driver_unregister(&tegra_gr3d_driver);
709 	platform_driver_unregister(&tegra_gr2d_driver);
710 	platform_driver_unregister(&tegra_hdmi_driver);
711 	platform_driver_unregister(&tegra_dc_driver);
712 	host1x_driver_unregister(&host1x_drm_driver);
713 }
714 module_exit(host1x_drm_exit);
715 
716 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
717 MODULE_DESCRIPTION("NVIDIA Tegra DRM driver");
718 MODULE_LICENSE("GPL v2");
719