linux/drivers/gpu/drm/drm_fb_cma_helper.c
Thierry Reding 0281324516 drm: fb: cma: Fail gracefully on allocation failure
The drm_gem_cma_create() function never returns NULL but rather an error
encoded in the return value using the ERR_PTR() macro. Callers therefore
need to check for errors using the IS_ERR() macro. This change allows
drivers to handle contiguous DMA allocation failures gracefully.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-10-23 10:14:58 +10:00

406 lines
10 KiB
C

/*
* drm kms/fb cma (contiguous memory allocator) helper functions
*
* Copyright (C) 2012 Analog Device Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*
* Based on udl_fbdev.c
* Copyright (C) 2012 Red Hat
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_fb_cma_helper.h>
#include <linux/module.h>
struct drm_fb_cma {
struct drm_framebuffer fb;
struct drm_gem_cma_object *obj[4];
};
struct drm_fbdev_cma {
struct drm_fb_helper fb_helper;
struct drm_fb_cma *fb;
};
static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
{
return container_of(helper, struct drm_fbdev_cma, fb_helper);
}
static inline struct drm_fb_cma *to_fb_cma(struct drm_framebuffer *fb)
{
return container_of(fb, struct drm_fb_cma, fb);
}
static void drm_fb_cma_destroy(struct drm_framebuffer *fb)
{
struct drm_fb_cma *fb_cma = to_fb_cma(fb);
int i;
for (i = 0; i < 4; i++) {
if (fb_cma->obj[i])
drm_gem_object_unreference_unlocked(&fb_cma->obj[i]->base);
}
drm_framebuffer_cleanup(fb);
kfree(fb_cma);
}
static int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
struct drm_file *file_priv, unsigned int *handle)
{
struct drm_fb_cma *fb_cma = to_fb_cma(fb);
return drm_gem_handle_create(file_priv,
&fb_cma->obj[0]->base, handle);
}
static struct drm_framebuffer_funcs drm_fb_cma_funcs = {
.destroy = drm_fb_cma_destroy,
.create_handle = drm_fb_cma_create_handle,
};
static struct drm_fb_cma *drm_fb_cma_alloc(struct drm_device *dev,
struct drm_mode_fb_cmd2 *mode_cmd, struct drm_gem_cma_object **obj,
unsigned int num_planes)
{
struct drm_fb_cma *fb_cma;
int ret;
int i;
fb_cma = kzalloc(sizeof(*fb_cma), GFP_KERNEL);
if (!fb_cma)
return ERR_PTR(-ENOMEM);
ret = drm_framebuffer_init(dev, &fb_cma->fb, &drm_fb_cma_funcs);
if (ret) {
dev_err(dev->dev, "Failed to initalize framebuffer: %d\n", ret);
kfree(fb_cma);
return ERR_PTR(ret);
}
drm_helper_mode_fill_fb_struct(&fb_cma->fb, mode_cmd);
for (i = 0; i < num_planes; i++)
fb_cma->obj[i] = obj[i];
return fb_cma;
}
/**
* drm_fb_cma_create() - (struct drm_mode_config_funcs *)->fb_create callback function
*
* If your hardware has special alignment or pitch requirements these should be
* checked before calling this function.
*/
struct drm_framebuffer *drm_fb_cma_create(struct drm_device *dev,
struct drm_file *file_priv, struct drm_mode_fb_cmd2 *mode_cmd)
{
struct drm_fb_cma *fb_cma;
struct drm_gem_cma_object *objs[4];
struct drm_gem_object *obj;
unsigned int hsub;
unsigned int vsub;
int ret;
int i;
hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);
for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
unsigned int width = mode_cmd->width / (i ? hsub : 1);
unsigned int height = mode_cmd->height / (i ? vsub : 1);
unsigned int min_size;
obj = drm_gem_object_lookup(dev, file_priv, mode_cmd->handles[i]);
if (!obj) {
dev_err(dev->dev, "Failed to lookup GEM object\n");
ret = -ENXIO;
goto err_gem_object_unreference;
}
min_size = (height - 1) * mode_cmd->pitches[i]
+ width * drm_format_plane_cpp(mode_cmd->pixel_format, i)
+ mode_cmd->offsets[i];
if (obj->size < min_size) {
drm_gem_object_unreference_unlocked(obj);
ret = -EINVAL;
goto err_gem_object_unreference;
}
objs[i] = to_drm_gem_cma_obj(obj);
}
fb_cma = drm_fb_cma_alloc(dev, mode_cmd, objs, i);
if (IS_ERR(fb_cma)) {
ret = PTR_ERR(fb_cma);
goto err_gem_object_unreference;
}
return &fb_cma->fb;
err_gem_object_unreference:
for (i--; i >= 0; i--)
drm_gem_object_unreference_unlocked(&objs[i]->base);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(drm_fb_cma_create);
/**
* drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
* @fb: The framebuffer
* @plane: Which plane
*
* Return the CMA GEM object for given framebuffer.
*
* This function will usually be called from the CRTC callback functions.
*/
struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
unsigned int plane)
{
struct drm_fb_cma *fb_cma = to_fb_cma(fb);
if (plane >= 4)
return NULL;
return fb_cma->obj[plane];
}
EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
static struct fb_ops drm_fbdev_cma_ops = {
.owner = THIS_MODULE,
.fb_fillrect = sys_fillrect,
.fb_copyarea = sys_copyarea,
.fb_imageblit = 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 drm_fbdev_cma_create(struct drm_fb_helper *helper,
struct drm_fb_helper_surface_size *sizes)
{
struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
struct drm_mode_fb_cmd2 mode_cmd = { 0 };
struct drm_device *dev = helper->dev;
struct drm_gem_cma_object *obj;
struct drm_framebuffer *fb;
unsigned int bytes_per_pixel;
unsigned long offset;
struct fb_info *fbi;
size_t size;
int ret;
DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
sizes->surface_width, sizes->surface_height,
sizes->surface_bpp);
bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
mode_cmd.width = sizes->surface_width;
mode_cmd.height = sizes->surface_height;
mode_cmd.pitches[0] = sizes->surface_width * bytes_per_pixel;
mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
sizes->surface_depth);
size = mode_cmd.pitches[0] * mode_cmd.height;
obj = drm_gem_cma_create(dev, size);
if (IS_ERR(obj))
return -ENOMEM;
fbi = framebuffer_alloc(0, dev->dev);
if (!fbi) {
dev_err(dev->dev, "Failed to allocate framebuffer info.\n");
ret = -ENOMEM;
goto err_drm_gem_cma_free_object;
}
fbdev_cma->fb = drm_fb_cma_alloc(dev, &mode_cmd, &obj, 1);
if (IS_ERR(fbdev_cma->fb)) {
dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
ret = PTR_ERR(fbdev_cma->fb);
goto err_framebuffer_release;
}
fb = &fbdev_cma->fb->fb;
helper->fb = fb;
helper->fbdev = fbi;
fbi->par = helper;
fbi->flags = FBINFO_FLAG_DEFAULT;
fbi->fbops = &drm_fbdev_cma_ops;
ret = fb_alloc_cmap(&fbi->cmap, 256, 0);
if (ret) {
dev_err(dev->dev, "Failed to allocate color map.\n");
goto err_drm_fb_cma_destroy;
}
drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
drm_fb_helper_fill_var(fbi, helper, fb->width, fb->height);
offset = fbi->var.xoffset * bytes_per_pixel;
offset += fbi->var.yoffset * fb->pitches[0];
dev->mode_config.fb_base = (resource_size_t)obj->paddr;
fbi->screen_base = obj->vaddr + offset;
fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
fbi->screen_size = size;
fbi->fix.smem_len = size;
return 0;
err_drm_fb_cma_destroy:
drm_fb_cma_destroy(fb);
err_framebuffer_release:
framebuffer_release(fbi);
err_drm_gem_cma_free_object:
drm_gem_cma_free_object(&obj->base);
return ret;
}
static int drm_fbdev_cma_probe(struct drm_fb_helper *helper,
struct drm_fb_helper_surface_size *sizes)
{
int ret = 0;
if (!helper->fb) {
ret = drm_fbdev_cma_create(helper, sizes);
if (ret < 0)
return ret;
ret = 1;
}
return ret;
}
static struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
.fb_probe = drm_fbdev_cma_probe,
};
/**
* drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
* @dev: DRM device
* @preferred_bpp: Preferred bits per pixel for the device
* @num_crtc: Number of CRTCs
* @max_conn_count: Maximum number of connectors
*
* Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
*/
struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
unsigned int preferred_bpp, unsigned int num_crtc,
unsigned int max_conn_count)
{
struct drm_fbdev_cma *fbdev_cma;
struct drm_fb_helper *helper;
int ret;
fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
if (!fbdev_cma) {
dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
return ERR_PTR(-ENOMEM);
}
fbdev_cma->fb_helper.funcs = &drm_fb_cma_helper_funcs;
helper = &fbdev_cma->fb_helper;
ret = drm_fb_helper_init(dev, helper, num_crtc, max_conn_count);
if (ret < 0) {
dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
goto err_free;
}
ret = drm_fb_helper_single_add_all_connectors(helper);
if (ret < 0) {
dev_err(dev->dev, "Failed to add connectors.\n");
goto err_drm_fb_helper_fini;
}
ret = drm_fb_helper_initial_config(helper, preferred_bpp);
if (ret < 0) {
dev_err(dev->dev, "Failed to set inital hw configuration.\n");
goto err_drm_fb_helper_fini;
}
return fbdev_cma;
err_drm_fb_helper_fini:
drm_fb_helper_fini(helper);
err_free:
kfree(fbdev_cma);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
/**
* drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
* @fbdev_cma: The drm_fbdev_cma struct
*/
void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
{
if (fbdev_cma->fb_helper.fbdev) {
struct fb_info *info;
int ret;
info = fbdev_cma->fb_helper.fbdev;
ret = unregister_framebuffer(info);
if (ret < 0)
DRM_DEBUG_KMS("failed unregister_framebuffer()\n");
if (info->cmap.len)
fb_dealloc_cmap(&info->cmap);
framebuffer_release(info);
}
if (fbdev_cma->fb)
drm_fb_cma_destroy(&fbdev_cma->fb->fb);
drm_fb_helper_fini(&fbdev_cma->fb_helper);
kfree(fbdev_cma);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
/**
* drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
* @fbdev_cma: The drm_fbdev_cma struct, may be NULL
*
* This function is usually called from the DRM drivers lastclose callback.
*/
void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
{
if (fbdev_cma)
drm_fb_helper_restore_fbdev_mode(&fbdev_cma->fb_helper);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
/**
* drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
* @fbdev_cma: The drm_fbdev_cma struct, may be NULL
*
* This function is usually called from the DRM drivers output_poll_changed
* callback.
*/
void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
{
if (fbdev_cma)
drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);