mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 12:28:41 +08:00
fbdev: add fb_read/fb_write functions for framebuffers in system RAM
The functions fb_read() and fb_write in fbmem.c assume that the framebuffer is in IO memory. However, we have 3 drivers (hecubafb, arcfb, and vfb) where the framebuffer is allocated from system RAM (via vmalloc). Using __raw_read/__raw_write (fb_readl/fb_writel) for these drivers is illegal, especially in other platforms. Create file read and write methods for these types of drivers. These are named fb_sys_read() and fb_sys_write(). Signed-off-by: Antonino Daplas <adaplas@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
3f9b0880e4
commit
09aaf268eb
@ -122,6 +122,11 @@ config FB_SYS_IMAGEBLIT
|
||||
blitting. This is used by drivers that don't provide their own
|
||||
(accelerated) version and the framebuffer is in system RAM.
|
||||
|
||||
config FB_SYS_FOPS
|
||||
tristate
|
||||
depends on FB
|
||||
default n
|
||||
|
||||
config FB_DEFERRED_IO
|
||||
bool
|
||||
depends on FB
|
||||
|
@ -21,6 +21,7 @@ obj-$(CONFIG_FB_CFB_IMAGEBLIT) += cfbimgblt.o
|
||||
obj-$(CONFIG_FB_SYS_FILLRECT) += sysfillrect.o
|
||||
obj-$(CONFIG_FB_SYS_COPYAREA) += syscopyarea.o
|
||||
obj-$(CONFIG_FB_SYS_IMAGEBLIT) += sysimgblt.o
|
||||
obj-$(CONFIG_FB_SYS_FOPS) += fb_sys_fops.o
|
||||
obj-$(CONFIG_FB_SVGALIB) += svgalib.o
|
||||
obj-$(CONFIG_FB_MACMODES) += macmodes.o
|
||||
obj-$(CONFIG_FB_DDC) += fb_ddc.o
|
||||
|
104
drivers/video/fb_sys_fops.c
Normal file
104
drivers/video/fb_sys_fops.c
Normal file
@ -0,0 +1,104 @@
|
||||
/*
|
||||
* linux/drivers/video/fb_sys_read.c - Generic file operations where
|
||||
* framebuffer is in system RAM
|
||||
*
|
||||
* Copyright (C) 2007 Antonino Daplas <adaplas@pol.net>
|
||||
*
|
||||
* This file is subject to the terms and conditions of the GNU General Public
|
||||
* License. See the file COPYING in the main directory of this archive
|
||||
* for more details.
|
||||
*
|
||||
*/
|
||||
#include <linux/fb.h>
|
||||
#include <linux/module.h>
|
||||
#include <asm/uaccess.h>
|
||||
|
||||
ssize_t fb_sys_read(struct fb_info *info, char __user *buf, size_t count,
|
||||
loff_t *ppos)
|
||||
{
|
||||
unsigned long p = *ppos;
|
||||
void *src;
|
||||
int err = 0;
|
||||
unsigned long total_size;
|
||||
|
||||
if (info->state != FBINFO_STATE_RUNNING)
|
||||
return -EPERM;
|
||||
|
||||
total_size = info->screen_size;
|
||||
|
||||
if (total_size == 0)
|
||||
total_size = info->fix.smem_len;
|
||||
|
||||
if (p >= total_size)
|
||||
return 0;
|
||||
|
||||
if (count >= total_size)
|
||||
count = total_size;
|
||||
|
||||
if (count + p > total_size)
|
||||
count = total_size - p;
|
||||
|
||||
src = (void __force *)(info->screen_base + p);
|
||||
|
||||
if (info->fbops->fb_sync)
|
||||
info->fbops->fb_sync(info);
|
||||
|
||||
if (copy_to_user(buf, src, count))
|
||||
err = -EFAULT;
|
||||
|
||||
if (!err)
|
||||
*ppos += count;
|
||||
|
||||
return (err) ? err : count;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(fb_sys_read);
|
||||
|
||||
ssize_t fb_sys_write(struct fb_info *info, const char __user *buf,
|
||||
size_t count, loff_t *ppos)
|
||||
{
|
||||
unsigned long p = *ppos;
|
||||
void *dst;
|
||||
int err = 0;
|
||||
unsigned long total_size;
|
||||
|
||||
if (info->state != FBINFO_STATE_RUNNING)
|
||||
return -EPERM;
|
||||
|
||||
total_size = info->screen_size;
|
||||
|
||||
if (total_size == 0)
|
||||
total_size = info->fix.smem_len;
|
||||
|
||||
if (p > total_size)
|
||||
return -EFBIG;
|
||||
|
||||
if (count > total_size) {
|
||||
err = -EFBIG;
|
||||
count = total_size;
|
||||
}
|
||||
|
||||
if (count + p > total_size) {
|
||||
if (!err)
|
||||
err = -ENOSPC;
|
||||
|
||||
count = total_size - p;
|
||||
}
|
||||
|
||||
dst = (void __force *) (info->screen_base + p);
|
||||
|
||||
if (info->fbops->fb_sync)
|
||||
info->fbops->fb_sync(info);
|
||||
|
||||
if (copy_from_user(dst, buf, count))
|
||||
err = -EFAULT;
|
||||
|
||||
if (!err)
|
||||
*ppos += count;
|
||||
|
||||
return (err) ? err : count;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(fb_sys_write);
|
||||
|
||||
MODULE_AUTHOR("Antonino Daplas <adaplas@pol.net>");
|
||||
MODULE_DESCRIPTION("Generic file read (fb in system RAM)");
|
||||
MODULE_LICENSE("GPL");
|
@ -903,6 +903,10 @@ extern void cfb_imageblit(struct fb_info *info, const struct fb_image *image);
|
||||
extern void sys_fillrect(struct fb_info *info, const struct fb_fillrect *rect);
|
||||
extern void sys_copyarea(struct fb_info *info, const struct fb_copyarea *area);
|
||||
extern void sys_imageblit(struct fb_info *info, const struct fb_image *image);
|
||||
extern ssize_t fb_sys_read(struct fb_info *info, char __user *buf,
|
||||
size_t count, loff_t *ppos);
|
||||
extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf,
|
||||
size_t count, loff_t *ppos);
|
||||
|
||||
/* drivers/video/fbmem.c */
|
||||
extern int register_framebuffer(struct fb_info *fb_info);
|
||||
|
Loading…
Reference in New Issue
Block a user