[PATCH] fbdev: fix the fb_find_nearest_mode() function

Currently the fb_find_nearest_mode() function finds a mode with screen
resolution closest to that described by the 'var' argument and with some
arbitrary refresh rate (eg.  in the following sequence of refresh rates: 70 60
53 85 75, 53 is selected).

This patch fixes the function so that it looks for the closest mode as far as
both resolution and refresh rate are concerned.  The function's first argument
is changed to fb_videomode so that the refresh rate can be specified by the
caller, as fb_var_screeninfo doesn't have any fields that could directly hold
this data.

Signed-off-by: Michal Januszewski <spock@gentoo.org>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 5ff51cd0a2a98c23484a17719ecc1ebe2f19d32a..3cf1b61ff1f8a1dfbdedade08a89cee7381e0c22 100644 (file)
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -2715,7 +2715,8 @@ static void fbcon_new_modelist(struct fb_info *info)
                        continue;
                vc = vc_cons[i].d;
                display_to_var(&var, &fb_display[i]);
-               mode = fb_find_nearest_mode(&var, &info->modelist);
+               mode = fb_find_nearest_mode(fb_display[i].mode,
+                                           &info->modelist);
                fb_videomode_to_var(&var, mode);
 
                if (vc)

diff --git a/drivers/video/modedb.c b/drivers/video/modedb.c
index 47516c44a390ac7218a3df538424553f76ac9225..aadef046ce7b3c1d91147d8f3c650e204a7cb4c5 100644 (file)
--- a/drivers/video/modedb.c
+++ b/drivers/video/modedb.c
@@ -676,6 +676,8 @@ void fb_var_to_videomode(struct fb_videomode *mode,
        mode->sync = var->sync;
        mode->vmode = var->vmode & FB_VMODE_MASK;
        mode->flag = FB_MODE_IS_FROM_VAR;
+       mode->refresh = 0;
+
        if (!var->pixclock)
                return;
 
@@ -785,39 +787,39 @@ struct fb_videomode *fb_find_best_mode(struct fb_var_screeninfo *var,
 }
 
 /**
- * fb_find_nearest_mode - find mode closest video mode
+ * fb_find_nearest_mode - find closest videomode
  *
- * @var: pointer to struct fb_var_screeninfo
+ * @mode: pointer to struct fb_videomode
  * @head: pointer to modelist
  *
  * Finds best matching videomode, smaller or greater in dimension.
  * If more than 1 videomode is found, will return the videomode with
- * the closest refresh rate
+ * the closest refresh rate.
  */
-struct fb_videomode *fb_find_nearest_mode(struct fb_var_screeninfo *var,
+struct fb_videomode *fb_find_nearest_mode(struct fb_videomode *mode,
                                          struct list_head *head)
 {
        struct list_head *pos;
        struct fb_modelist *modelist;
-       struct fb_videomode *mode, *best = NULL;
+       struct fb_videomode *cmode, *best = NULL;
        u32 diff = -1, diff_refresh = -1;
 
        list_for_each(pos, head) {
                u32 d;
 
                modelist = list_entry(pos, struct fb_modelist, list);
-               mode = &modelist->mode;
+               cmode = &modelist->mode;
 
-               d = abs(mode->xres - var->xres) +
-                       abs(mode->yres - var->yres);
+               d = abs(cmode->xres - mode->xres) +
+                       abs(cmode->yres - mode->yres);
                if (diff > d) {
                        diff = d;
-                       best = mode;
+                       best = cmode;
                } else if (diff == d) {
-                       d = abs(mode->refresh - best->refresh);
+                       d = abs(cmode->refresh - mode->refresh);
                        if (diff_refresh > d) {
                                diff_refresh = d;
-                               best = mode;
+                               best = cmode;
                        }
                }
        }

diff --git a/include/linux/fb.h b/include/linux/fb.h
index 008ea71f4d7fbee7f790877cb5e2f5e537728c41..68a787914d85b4a783fddc068406ac61c025ba0b 100644 (file)
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -897,7 +897,7 @@ extern struct fb_videomode *fb_match_mode(struct fb_var_screeninfo *var,
                                          struct list_head *head);
 extern struct fb_videomode *fb_find_best_mode(struct fb_var_screeninfo *var,
                                              struct list_head *head);
-extern struct fb_videomode *fb_find_nearest_mode(struct fb_var_screeninfo *var,
+extern struct fb_videomode *fb_find_nearest_mode(struct fb_videomode *mode,
                                                 struct list_head *head);
 extern void fb_destroy_modelist(struct list_head *head);
 extern void fb_videomode_to_modelist(struct fb_videomode *modedb, int num,