drivers/gpu/drm/tegra/fb.c - kernel/quantenna - Git at Google

 /*
  * Copyright (C) 2012-2013 Avionic Design GmbH
  * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
  *
  * Based on the KMS/FB CMA helpers
  *   Copyright (C) 2012 Analog Device Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/console.h>

 #include "drm.h"
 #include "gem.h"

 static inline struct tegra_fb *to_tegra_fb(struct drm_framebuffer *fb)
 {
 	return container_of(fb, struct tegra_fb, base);
 }

 #ifdef CONFIG_DRM_FBDEV_EMULATION
 static inline struct tegra_fbdev *to_tegra_fbdev(struct drm_fb_helper *helper)
 {
 	return container_of(helper, struct tegra_fbdev, base);
 }
 #endif

 struct tegra_bo *tegra_fb_get_plane(struct drm_framebuffer *framebuffer,
 				    unsigned int index)
 {
 	struct tegra_fb *fb = to_tegra_fb(framebuffer);

 	if (index >= drm_format_num_planes(framebuffer->pixel_format))
 		return NULL;

 	return fb->planes[index];
 }

 bool tegra_fb_is_bottom_up(struct drm_framebuffer *framebuffer)
 {
 	struct tegra_fb *fb = to_tegra_fb(framebuffer);

 	if (fb->planes[0]->flags & TEGRA_BO_BOTTOM_UP)
 		return true;

 	return false;
 }

 int tegra_fb_get_tiling(struct drm_framebuffer *framebuffer,
 			struct tegra_bo_tiling *tiling)
 {
 	struct tegra_fb *fb = to_tegra_fb(framebuffer);

 	/* TODO: handle YUV formats? */
 	*tiling = fb->planes[0]->tiling;

 	return 0;
 }

 static void tegra_fb_destroy(struct drm_framebuffer *framebuffer)
 {
 	struct tegra_fb *fb = to_tegra_fb(framebuffer);
 	unsigned int i;

 	for (i = 0; i < fb->num_planes; i++) {
 		struct tegra_bo *bo = fb->planes[i];

 		if (bo) {
 			if (bo->pages && bo->vaddr)
 				vunmap(bo->vaddr);

 			drm_gem_object_unreference_unlocked(&bo->gem);
 		}
 	}

 	drm_framebuffer_cleanup(framebuffer);
 	kfree(fb->planes);
 	kfree(fb);
 }

 static int tegra_fb_create_handle(struct drm_framebuffer *framebuffer,
 				  struct drm_file *file, unsigned int *handle)
 {
 	struct tegra_fb *fb = to_tegra_fb(framebuffer);

 	return drm_gem_handle_create(file, &fb->planes[0]->gem, handle);
 }

 static const struct drm_framebuffer_funcs tegra_fb_funcs = {
 	.destroy = tegra_fb_destroy,
 	.create_handle = tegra_fb_create_handle,
 };

 static struct tegra_fb *tegra_fb_alloc(struct drm_device *drm,
 				       const struct drm_mode_fb_cmd2 *mode_cmd,
 				       struct tegra_bo **planes,
 				       unsigned int num_planes)
 {
 	struct tegra_fb *fb;
 	unsigned int i;
 	int err;

 	fb = kzalloc(sizeof(*fb), GFP_KERNEL);
 	if (!fb)
 		return ERR_PTR(-ENOMEM);

 	fb->planes = kzalloc(num_planes * sizeof(*planes), GFP_KERNEL);
 	if (!fb->planes) {
 		kfree(fb);
 		return ERR_PTR(-ENOMEM);
 	}

 	fb->num_planes = num_planes;

 	drm_helper_mode_fill_fb_struct(&fb->base, mode_cmd);

 	for (i = 0; i < fb->num_planes; i++)
 		fb->planes[i] = planes[i];

 	err = drm_framebuffer_init(drm, &fb->base, &tegra_fb_funcs);
 	if (err < 0) {
 		dev_err(drm->dev, "failed to initialize framebuffer: %d\n",
 			err);
 		kfree(fb->planes);
 		kfree(fb);
 		return ERR_PTR(err);
 	}

 	return fb;
 }

 struct drm_framebuffer *tegra_fb_create(struct drm_device *drm,
 					struct drm_file *file,
 					const struct drm_mode_fb_cmd2 *cmd)
 {
 	unsigned int hsub, vsub, i;
 	struct tegra_bo *planes[4];
 	struct drm_gem_object *gem;
 	struct tegra_fb *fb;
 	int err;

 	hsub = drm_format_horz_chroma_subsampling(cmd->pixel_format);
 	vsub = drm_format_vert_chroma_subsampling(cmd->pixel_format);

 	for (i = 0; i < drm_format_num_planes(cmd->pixel_format); i++) {
 		unsigned int width = cmd->width / (i ? hsub : 1);
 		unsigned int height = cmd->height / (i ? vsub : 1);
 		unsigned int size, bpp;

 		gem = drm_gem_object_lookup(file, cmd->handles[i]);
 		if (!gem) {
 			err = -ENXIO;
 			goto unreference;
 		}

 		bpp = drm_format_plane_cpp(cmd->pixel_format, i);

 		size = (height - 1) * cmd->pitches[i] +
 		       width * bpp + cmd->offsets[i];

 		if (gem->size < size) {
 			err = -EINVAL;
 			goto unreference;
 		}

 		planes[i] = to_tegra_bo(gem);
 	}

 	fb = tegra_fb_alloc(drm, cmd, planes, i);
 	if (IS_ERR(fb)) {
 		err = PTR_ERR(fb);
 		goto unreference;
 	}

 	return &fb->base;

 unreference:
 	while (i--)
 		drm_gem_object_unreference_unlocked(&planes[i]->gem);

 	return ERR_PTR(err);
 }

 #ifdef CONFIG_DRM_FBDEV_EMULATION
 static struct fb_ops tegra_fb_ops = {
 	.owner = THIS_MODULE,
 	.fb_fillrect = drm_fb_helper_sys_fillrect,
 	.fb_copyarea = drm_fb_helper_sys_copyarea,
 	.fb_imageblit = drm_fb_helper_sys_imageblit,
 	.fb_check_var = drm_fb_helper_check_var,
 	.fb_set_par = drm_fb_helper_set_par,
 	.fb_blank = drm_fb_helper_blank,
 	.fb_pan_display = drm_fb_helper_pan_display,
 	.fb_setcmap = drm_fb_helper_setcmap,
 };

 static int tegra_fbdev_probe(struct drm_fb_helper *helper,
 			     struct drm_fb_helper_surface_size *sizes)
 {
 	struct tegra_fbdev *fbdev = to_tegra_fbdev(helper);
 	struct tegra_drm *tegra = helper->dev->dev_private;
 	struct drm_device *drm = helper->dev;
 	struct drm_mode_fb_cmd2 cmd = { 0 };
 	unsigned int bytes_per_pixel;
 	struct drm_framebuffer *fb;
 	unsigned long offset;
 	struct fb_info *info;
 	struct tegra_bo *bo;
 	size_t size;
 	int err;

 	bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);

 	cmd.width = sizes->surface_width;
 	cmd.height = sizes->surface_height;
 	cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
 				  tegra->pitch_align);
 	cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 						     sizes->surface_depth);

 	size = cmd.pitches[0] * cmd.height;

 	bo = tegra_bo_create(drm, size, 0);
 	if (IS_ERR(bo))
 		return PTR_ERR(bo);

 	info = drm_fb_helper_alloc_fbi(helper);
 	if (IS_ERR(info)) {
 		dev_err(drm->dev, "failed to allocate framebuffer info\n");
 		drm_gem_object_unreference_unlocked(&bo->gem);
 		return PTR_ERR(info);
 	}

 	fbdev->fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
 	if (IS_ERR(fbdev->fb)) {
 		err = PTR_ERR(fbdev->fb);
 		dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
 			err);
 		drm_gem_object_unreference_unlocked(&bo->gem);
 		goto release;
 	}

 	fb = &fbdev->fb->base;
 	helper->fb = fb;
 	helper->fbdev = info;

 	info->par = helper;
 	info->flags = FBINFO_FLAG_DEFAULT;
 	info->fbops = &tegra_fb_ops;

 	drm_fb_helper_fill_fix(info, fb->pitches[0], fb->depth);
 	drm_fb_helper_fill_var(info, helper, fb->width, fb->height);

 	offset = info->var.xoffset * bytes_per_pixel +
 		 info->var.yoffset * fb->pitches[0];

 	if (bo->pages) {
 		bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
 				 pgprot_writecombine(PAGE_KERNEL));
 		if (!bo->vaddr) {
 			dev_err(drm->dev, "failed to vmap() framebuffer\n");
 			err = -ENOMEM;
 			goto destroy;
 		}
 	}

 	drm->mode_config.fb_base = (resource_size_t)bo->paddr;
 	info->screen_base = (void __iomem *)bo->vaddr + offset;
 	info->screen_size = size;
 	info->fix.smem_start = (unsigned long)(bo->paddr + offset);
 	info->fix.smem_len = size;

 	return 0;

 destroy:
 	drm_framebuffer_unregister_private(fb);
 	tegra_fb_destroy(fb);
 release:
 	drm_fb_helper_release_fbi(helper);
 	return err;
 }

 static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
 	.fb_probe = tegra_fbdev_probe,
 };

 static struct tegra_fbdev *tegra_fbdev_create(struct drm_device *drm)
 {
 	struct tegra_fbdev *fbdev;

 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
 	if (!fbdev) {
 		dev_err(drm->dev, "failed to allocate DRM fbdev\n");
 		return ERR_PTR(-ENOMEM);
 	}

 	drm_fb_helper_prepare(drm, &fbdev->base, &tegra_fb_helper_funcs);

 	return fbdev;
 }

 static void tegra_fbdev_free(struct tegra_fbdev *fbdev)
 {
 	kfree(fbdev);
 }

 static int tegra_fbdev_init(struct tegra_fbdev *fbdev,
 			    unsigned int preferred_bpp,
 			    unsigned int num_crtc,
 			    unsigned int max_connectors)
 {
 	struct drm_device *drm = fbdev->base.dev;
 	int err;

 	err = drm_fb_helper_init(drm, &fbdev->base, num_crtc, max_connectors);
 	if (err < 0) {
 		dev_err(drm->dev, "failed to initialize DRM FB helper: %d\n",
 			err);
 		return err;
 	}

 	err = drm_fb_helper_single_add_all_connectors(&fbdev->base);
 	if (err < 0) {
 		dev_err(drm->dev, "failed to add connectors: %d\n", err);
 		goto fini;
 	}

 	err = drm_fb_helper_initial_config(&fbdev->base, preferred_bpp);
 	if (err < 0) {
 		dev_err(drm->dev, "failed to set initial configuration: %d\n",
 			err);
 		goto fini;
 	}

 	return 0;

 fini:
 	drm_fb_helper_fini(&fbdev->base);
 	return err;
 }

 static void tegra_fbdev_exit(struct tegra_fbdev *fbdev)
 {
 	drm_fb_helper_unregister_fbi(&fbdev->base);
 	drm_fb_helper_release_fbi(&fbdev->base);

 	if (fbdev->fb) {
 		drm_framebuffer_unregister_private(&fbdev->fb->base);
 		drm_framebuffer_remove(&fbdev->fb->base);
 	}

 	drm_fb_helper_fini(&fbdev->base);
 	tegra_fbdev_free(fbdev);
 }

 void tegra_fbdev_restore_mode(struct tegra_fbdev *fbdev)
 {
 	if (fbdev)
 		drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev->base);
 }

 void tegra_fb_output_poll_changed(struct drm_device *drm)
 {
 	struct tegra_drm *tegra = drm->dev_private;

 	if (tegra->fbdev)
 		drm_fb_helper_hotplug_event(&tegra->fbdev->base);
 }
 #endif

 int tegra_drm_fb_prepare(struct drm_device *drm)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct tegra_drm *tegra = drm->dev_private;

 	tegra->fbdev = tegra_fbdev_create(drm);
 	if (IS_ERR(tegra->fbdev))
 		return PTR_ERR(tegra->fbdev);
 #endif

 	return 0;
 }

 void tegra_drm_fb_free(struct drm_device *drm)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct tegra_drm *tegra = drm->dev_private;

 	tegra_fbdev_free(tegra->fbdev);
 #endif
 }

 int tegra_drm_fb_init(struct drm_device *drm)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct tegra_drm *tegra = drm->dev_private;
 	int err;

 	err = tegra_fbdev_init(tegra->fbdev, 32, drm->mode_config.num_crtc,
 			       drm->mode_config.num_connector);
 	if (err < 0)
 		return err;
 #endif

 	return 0;
 }

 void tegra_drm_fb_exit(struct drm_device *drm)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct tegra_drm *tegra = drm->dev_private;

 	tegra_fbdev_exit(tegra->fbdev);
 #endif
 }

 void tegra_drm_fb_suspend(struct drm_device *drm)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct tegra_drm *tegra = drm->dev_private;

 	console_lock();
 	drm_fb_helper_set_suspend(&tegra->fbdev->base, 1);
 	console_unlock();
 #endif
 }

 void tegra_drm_fb_resume(struct drm_device *drm)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct tegra_drm *tegra = drm->dev_private;

 	console_lock();
 	drm_fb_helper_set_suspend(&tegra->fbdev->base, 0);
 	console_unlock();
 #endif
 }
	/*
	* Copyright (C) 2012-2013 Avionic Design GmbH
	* Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
	*
	* Based on the KMS/FB CMA helpers
	* Copyright (C) 2012 Analog Device Inc.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/console.h>

	#include "drm.h"
	#include "gem.h"

	static inline struct tegra_fb to_tegra_fb(struct drm_framebuffer fb)
	{
	return container_of(fb, struct tegra_fb, base);
	}

	#ifdef CONFIG_DRM_FBDEV_EMULATION
	static inline struct tegra_fbdev to_tegra_fbdev(struct drm_fb_helper helper)
	{
	return container_of(helper, struct tegra_fbdev, base);
	}
	#endif

	struct tegra_bo tegra_fb_get_plane(struct drm_framebuffer framebuffer,
	unsigned int index)
	{
	struct tegra_fb *fb = to_tegra_fb(framebuffer);

	if (index >= drm_format_num_planes(framebuffer->pixel_format))
	return NULL;

	return fb->planes[index];
	}

	bool tegra_fb_is_bottom_up(struct drm_framebuffer *framebuffer)
	{
	struct tegra_fb *fb = to_tegra_fb(framebuffer);

	if (fb->planes[0]->flags & TEGRA_BO_BOTTOM_UP)
	return true;

	return false;
	}

	int tegra_fb_get_tiling(struct drm_framebuffer *framebuffer,
	struct tegra_bo_tiling *tiling)
	{
	struct tegra_fb *fb = to_tegra_fb(framebuffer);

	/* TODO: handle YUV formats? */
	*tiling = fb->planes[0]->tiling;

	return 0;
	}

	static void tegra_fb_destroy(struct drm_framebuffer *framebuffer)
	{
	struct tegra_fb *fb = to_tegra_fb(framebuffer);
	unsigned int i;

	for (i = 0; i < fb->num_planes; i++) {
	struct tegra_bo *bo = fb->planes[i];

	if (bo) {
	if (bo->pages && bo->vaddr)
	vunmap(bo->vaddr);

	drm_gem_object_unreference_unlocked(&bo->gem);
	}
	}

	drm_framebuffer_cleanup(framebuffer);
	kfree(fb->planes);
	kfree(fb);
	}

	static int tegra_fb_create_handle(struct drm_framebuffer *framebuffer,
	struct drm_file file, unsigned int handle)
	{
	struct tegra_fb *fb = to_tegra_fb(framebuffer);

	return drm_gem_handle_create(file, &fb->planes[0]->gem, handle);
	}

	static const struct drm_framebuffer_funcs tegra_fb_funcs = {
	.destroy = tegra_fb_destroy,
	.create_handle = tegra_fb_create_handle,
	};

	static struct tegra_fb tegra_fb_alloc(struct drm_device drm,
	const struct drm_mode_fb_cmd2 *mode_cmd,
	struct tegra_bo **planes,
	unsigned int num_planes)
	{
	struct tegra_fb *fb;
	unsigned int i;
	int err;

	fb = kzalloc(sizeof(*fb), GFP_KERNEL);
	if (!fb)
	return ERR_PTR(-ENOMEM);

	fb->planes = kzalloc(num_planes * sizeof(*planes), GFP_KERNEL);
	if (!fb->planes) {
	kfree(fb);
	return ERR_PTR(-ENOMEM);
	}

	fb->num_planes = num_planes;

	drm_helper_mode_fill_fb_struct(&fb->base, mode_cmd);

	for (i = 0; i < fb->num_planes; i++)
	fb->planes[i] = planes[i];

	err = drm_framebuffer_init(drm, &fb->base, &tegra_fb_funcs);
	if (err < 0) {
	dev_err(drm->dev, "failed to initialize framebuffer: %d\n",
	err);
	kfree(fb->planes);
	kfree(fb);
	return ERR_PTR(err);
	}

	return fb;
	}

	struct drm_framebuffer tegra_fb_create(struct drm_device drm,
	struct drm_file *file,
	const struct drm_mode_fb_cmd2 *cmd)
	{
	unsigned int hsub, vsub, i;
	struct tegra_bo *planes[4];
	struct drm_gem_object *gem;
	struct tegra_fb *fb;
	int err;

	hsub = drm_format_horz_chroma_subsampling(cmd->pixel_format);
	vsub = drm_format_vert_chroma_subsampling(cmd->pixel_format);

	for (i = 0; i < drm_format_num_planes(cmd->pixel_format); i++) {
	unsigned int width = cmd->width / (i ? hsub : 1);
	unsigned int height = cmd->height / (i ? vsub : 1);
	unsigned int size, bpp;

	gem = drm_gem_object_lookup(file, cmd->handles[i]);
	if (!gem) {
	err = -ENXIO;
	goto unreference;
	}

	bpp = drm_format_plane_cpp(cmd->pixel_format, i);

	size = (height - 1) * cmd->pitches[i] +
	width * bpp + cmd->offsets[i];

	if (gem->size < size) {
	err = -EINVAL;
	goto unreference;
	}

	planes[i] = to_tegra_bo(gem);
	}

	fb = tegra_fb_alloc(drm, cmd, planes, i);
	if (IS_ERR(fb)) {
	err = PTR_ERR(fb);
	goto unreference;
	}

	return &fb->base;

	unreference:
	while (i--)
	drm_gem_object_unreference_unlocked(&planes[i]->gem);

	return ERR_PTR(err);
	}

	#ifdef CONFIG_DRM_FBDEV_EMULATION
	static struct fb_ops tegra_fb_ops = {
	.owner = THIS_MODULE,
	.fb_fillrect = drm_fb_helper_sys_fillrect,
	.fb_copyarea = drm_fb_helper_sys_copyarea,
	.fb_imageblit = drm_fb_helper_sys_imageblit,
	.fb_check_var = drm_fb_helper_check_var,
	.fb_set_par = drm_fb_helper_set_par,
	.fb_blank = drm_fb_helper_blank,
	.fb_pan_display = drm_fb_helper_pan_display,
	.fb_setcmap = drm_fb_helper_setcmap,
	};

	static int tegra_fbdev_probe(struct drm_fb_helper *helper,
	struct drm_fb_helper_surface_size *sizes)
	{
	struct tegra_fbdev *fbdev = to_tegra_fbdev(helper);
	struct tegra_drm *tegra = helper->dev->dev_private;
	struct drm_device *drm = helper->dev;
	struct drm_mode_fb_cmd2 cmd = { 0 };
	unsigned int bytes_per_pixel;
	struct drm_framebuffer *fb;
	unsigned long offset;
	struct fb_info *info;
	struct tegra_bo *bo;
	size_t size;
	int err;

	bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);

	cmd.width = sizes->surface_width;
	cmd.height = sizes->surface_height;
	cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
	tegra->pitch_align);
	cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
	sizes->surface_depth);

	size = cmd.pitches[0] * cmd.height;

	bo = tegra_bo_create(drm, size, 0);
	if (IS_ERR(bo))
	return PTR_ERR(bo);

	info = drm_fb_helper_alloc_fbi(helper);
	if (IS_ERR(info)) {
	dev_err(drm->dev, "failed to allocate framebuffer info\n");
	drm_gem_object_unreference_unlocked(&bo->gem);
	return PTR_ERR(info);
	}

	fbdev->fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
	if (IS_ERR(fbdev->fb)) {
	err = PTR_ERR(fbdev->fb);
	dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
	err);
	drm_gem_object_unreference_unlocked(&bo->gem);
	goto release;
	}

	fb = &fbdev->fb->base;
	helper->fb = fb;
	helper->fbdev = info;

	info->par = helper;
	info->flags = FBINFO_FLAG_DEFAULT;
	info->fbops = &tegra_fb_ops;

	drm_fb_helper_fill_fix(info, fb->pitches[0], fb->depth);
	drm_fb_helper_fill_var(info, helper, fb->width, fb->height);

	offset = info->var.xoffset * bytes_per_pixel +
	info->var.yoffset * fb->pitches[0];

	if (bo->pages) {
	bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
	pgprot_writecombine(PAGE_KERNEL));
	if (!bo->vaddr) {
	dev_err(drm->dev, "failed to vmap() framebuffer\n");
	err = -ENOMEM;
	goto destroy;
	}
	}

	drm->mode_config.fb_base = (resource_size_t)bo->paddr;
	info->screen_base = (void __iomem *)bo->vaddr + offset;
	info->screen_size = size;
	info->fix.smem_start = (unsigned long)(bo->paddr + offset);
	info->fix.smem_len = size;

	return 0;

	destroy:
	drm_framebuffer_unregister_private(fb);
	tegra_fb_destroy(fb);
	release:
	drm_fb_helper_release_fbi(helper);
	return err;
	}

	static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
	.fb_probe = tegra_fbdev_probe,
	};

	static struct tegra_fbdev tegra_fbdev_create(struct drm_device drm)
	{
	struct tegra_fbdev *fbdev;

	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
	if (!fbdev) {
	dev_err(drm->dev, "failed to allocate DRM fbdev\n");
	return ERR_PTR(-ENOMEM);
	}

	drm_fb_helper_prepare(drm, &fbdev->base, &tegra_fb_helper_funcs);

	return fbdev;
	}

	static void tegra_fbdev_free(struct tegra_fbdev *fbdev)
	{
	kfree(fbdev);
	}

	static int tegra_fbdev_init(struct tegra_fbdev *fbdev,
	unsigned int preferred_bpp,
	unsigned int num_crtc,
	unsigned int max_connectors)
	{
	struct drm_device *drm = fbdev->base.dev;
	int err;

	err = drm_fb_helper_init(drm, &fbdev->base, num_crtc, max_connectors);
	if (err < 0) {
	dev_err(drm->dev, "failed to initialize DRM FB helper: %d\n",
	err);
	return err;
	}

	err = drm_fb_helper_single_add_all_connectors(&fbdev->base);
	if (err < 0) {
	dev_err(drm->dev, "failed to add connectors: %d\n", err);
	goto fini;
	}

	err = drm_fb_helper_initial_config(&fbdev->base, preferred_bpp);
	if (err < 0) {
	dev_err(drm->dev, "failed to set initial configuration: %d\n",
	err);
	goto fini;
	}

	return 0;

	fini:
	drm_fb_helper_fini(&fbdev->base);
	return err;
	}

	static void tegra_fbdev_exit(struct tegra_fbdev *fbdev)
	{
	drm_fb_helper_unregister_fbi(&fbdev->base);
	drm_fb_helper_release_fbi(&fbdev->base);

	if (fbdev->fb) {
	drm_framebuffer_unregister_private(&fbdev->fb->base);
	drm_framebuffer_remove(&fbdev->fb->base);
	}

	drm_fb_helper_fini(&fbdev->base);
	tegra_fbdev_free(fbdev);
	}

	void tegra_fbdev_restore_mode(struct tegra_fbdev *fbdev)
	{
	if (fbdev)
	drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev->base);
	}

	void tegra_fb_output_poll_changed(struct drm_device *drm)
	{
	struct tegra_drm *tegra = drm->dev_private;

	if (tegra->fbdev)
	drm_fb_helper_hotplug_event(&tegra->fbdev->base);
	}
	#endif

	int tegra_drm_fb_prepare(struct drm_device *drm)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct tegra_drm *tegra = drm->dev_private;

	tegra->fbdev = tegra_fbdev_create(drm);
	if (IS_ERR(tegra->fbdev))
	return PTR_ERR(tegra->fbdev);
	#endif

	return 0;
	}

	void tegra_drm_fb_free(struct drm_device *drm)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct tegra_drm *tegra = drm->dev_private;

	tegra_fbdev_free(tegra->fbdev);
	#endif
	}

	int tegra_drm_fb_init(struct drm_device *drm)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct tegra_drm *tegra = drm->dev_private;
	int err;

	err = tegra_fbdev_init(tegra->fbdev, 32, drm->mode_config.num_crtc,
	drm->mode_config.num_connector);
	if (err < 0)
	return err;
	#endif

	return 0;
	}

	void tegra_drm_fb_exit(struct drm_device *drm)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct tegra_drm *tegra = drm->dev_private;

	tegra_fbdev_exit(tegra->fbdev);
	#endif
	}

	void tegra_drm_fb_suspend(struct drm_device *drm)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct tegra_drm *tegra = drm->dev_private;

	console_lock();
	drm_fb_helper_set_suspend(&tegra->fbdev->base, 1);
	console_unlock();
	#endif
	}

	void tegra_drm_fb_resume(struct drm_device *drm)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct tegra_drm *tegra = drm->dev_private;

	console_lock();
	drm_fb_helper_set_suspend(&tegra->fbdev->base, 0);
	console_unlock();
	#endif
	}