fbcon: font setting should check limitation of driver

fbcon_set_font() will now check if the new font dimensions can be drawn by the
driver (by checking pixmap.blit_x and blit_y).  Similarly, add 2 new
parameters to get_default_font(), font_w and font_h, to further aid in the
font selection process.

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>

1 files changed, 14 insertions, 3 deletions

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 19dfdfbd4341..c71a88d531cd 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -988,7 +988,9 @@ static const char *fbcon_startup(void)
         if (!p->fontdata) {
                 if (!fontname[0] || !(font = find_font(fontname)))
                         font = get_default_font(info->var.xres,
-                                                info->var.yres);
+                                                info->var.yres,
+                                                info->pixmap.blit_x,
+                                                info->pixmap.blit_y);
                 vc->vc_font.width = font->width;
                 vc->vc_font.height = font->height;
                 vc->vc_font.data = (void *)(p->fontdata = font->data);
@@ -1108,7 +1110,9 @@ static void fbcon_init(struct vc_data *vc, int init)
 
                         if (!fontname[0] || !(font = find_font(fontname)))
                                 font = get_default_font(info->var.xres,
-                                                        info->var.yres);
+                                                        info->var.yres,
+                                                        info->pixmap.blit_x,
+                                                        info->pixmap.blit_y);
                         vc->vc_font.width = font->width;
                         vc->vc_font.height = font->height;
                         vc->vc_font.data = (void *)(p->fontdata = font->data);
@@ -2495,6 +2499,7 @@ static int fbcon_copy_font(struct vc_data *vc, int con)
 
 static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigned flags)
 {
+        struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
         unsigned charcount = font->charcount;
         int w = font->width;
         int h = font->height;
@@ -2508,6 +2513,11 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigne
         if (charcount != 256 && charcount != 512)
                 return -EINVAL;
 
+        /* Make sure drawing engine can handle the font */
+        if (!(info->pixmap.blit_x & (1 << (font->width - 1))) ||
+            !(info->pixmap.blit_y & (1 << (font->height - 1))))
+                return -EINVAL;
+
         size = h * pitch * charcount;
 
         new_data = kmalloc(FONT_EXTRA_WORDS * sizeof(int) + size, GFP_USER);
@@ -2552,7 +2562,8 @@ static int fbcon_set_def_font(struct vc_data *vc, struct console_font *font, cha
         const struct font_desc *f;
 
         if (!name)
-                f = get_default_font(info->var.xres, info->var.yres);
+                f = get_default_font(info->var.xres, info->var.yres,
+                                     info->pixmap.blit_x, info->pixmap.blit_y);
         else if (!(f = find_font(name)))
                 return -ENOENT;