leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

staging: udlfb: fbdev character read and write support

Browse Source 
Restore fbdev character read and write support

Enables access to the framebuffer from simple reads and writes
to /dev/fb0 (or fb1, ...). Low performance, because of extra copy
and because udlfb must scan every pixel for changes. But very
useful for testing and simple image display, etc.

Signed-off-by: Bernie Thompson <bernie@plugable.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Bernie Thompson 2010-09-05 16:35:04 -07:00 committed by Greg Kroah-Hartman
parent df9be302a2
commit d46ecb9f79
1 changed files with 44 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
drivers/staging/udlfb/udlfb.c
View File

@ -602,6 +602,48 @@ int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
return 0;
}
static ssize_t dlfb_ops_read(struct fb_info *info, char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t result = -ENOSYS;
#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
result = fb_sys_read(info, buf, count, ppos);
#endif
return result;
}
/*
* Path triggered by usermode clients who write to filesystem
* e.g. cat filename > /dev/fb1
* Not used by X Windows or text-mode console. But useful for testing.
* Slow because of extra copy and we must assume all pixels dirty.
*/
static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t result = -ENOSYS;
struct dlfb_data *dev = info->par;
u32 offset = (u32) *ppos;
#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
result = fb_sys_write(info, buf, count, ppos);
if (result > 0) {
int start = max((int)(offset / info->fix.line_length) - 1, 0);
int lines = min((u32)((result / info->fix.line_length) + 1),
(u32)info->var.yres);
dlfb_handle_damage(dev, 0, start, info->var.xres,
lines, info->screen_base);
}
#endif
return result;
}
/* hardware has native COPY command (see libdlo), but not worth it for fbcon */
static void dlfb_ops_copyarea(struct fb_info *info,
const struct fb_copyarea *area)
@ -924,6 +966,8 @@ static int dlfb_ops_blank(int blank_mode, struct fb_info *info)
static struct fb_ops dlfb_ops = {
.owner = THIS_MODULE,
.fb_read = dlfb_ops_read,
.fb_write = dlfb_ops_write,
.fb_setcolreg = dlfb_ops_setcolreg,
.fb_fillrect = dlfb_ops_fillrect,
.fb_copyarea = dlfb_ops_copyarea,