* struct s3c_fb_win_variant
  * @has_osd_c: Set if has OSD C register.
  * @has_osd_d: Set if has OSD D register.
+ * @has_osd_alpha: Set if can change alpha transparency for a window.
  * @palette_sz: Size of palette in entries.
  * @palette_16bpp: Set if palette is 16bits wide.
+ * @osd_size_off: If != 0, supports setting up OSD for a window; the appropriate
+ *                register is located at the given offset from OSD_BASE.
  * @valid_bpp: 1 bit per BPP setting to show valid bits-per-pixel.
  *
  * valid_bpp bit x is set if (x+1)BPP is supported.
 struct s3c_fb_win_variant {
        unsigned int    has_osd_c:1;
        unsigned int    has_osd_d:1;
+       unsigned int    has_osd_alpha:1;
        unsigned int    palette_16bpp:1;
+       unsigned short  osd_size_off;
        unsigned short  palette_sz;
        u32             valid_bpp;
 };
        return ALIGN(pix, pix_per_word);
 }
 
+/**
+ * vidosd_set_size() - set OSD size for a window
+ *
+ * @win: the window to set OSD size for
+ * @size: OSD size register value
+ */
+static void vidosd_set_size(struct s3c_fb_win *win, u32 size)
+{
+       struct s3c_fb *sfb = win->parent;
+
+       /* OSD can be set up if osd_size_off != 0 for this window */
+       if (win->variant.osd_size_off)
+               writel(size, sfb->regs + OSD_BASE(win->index, sfb->variant)
+                               + win->variant.osd_size_off);
+}
+
+/**
+ * vidosd_set_alpha() - set alpha transparency for a window
+ *
+ * @win: the window to set OSD size for
+ * @alpha: alpha register value
+ */
+static void vidosd_set_alpha(struct s3c_fb_win *win, u32 alpha)
+{
+       struct s3c_fb *sfb = win->parent;
+
+       if (win->variant.has_osd_alpha)
+               writel(alpha, sfb->regs + VIDOSD_C(win->index, sfb->variant));
+}
+
 /**
  * shadow_protect_win() - disable updating values from shadow registers at vsync
  *
        void __iomem *regs = sfb->regs;
        void __iomem *buf = regs;
        int win_no = win->index;
-       u32 osdc_data = 0;
+       u32 alpha = 0;
        u32 data;
        u32 pagewidth;
        int clkdiv;
 
        data = var->xres * var->yres;
 
-       osdc_data = VIDISD14C_ALPHA1_R(0xf) |
+       alpha = VIDISD14C_ALPHA1_R(0xf) |
                VIDISD14C_ALPHA1_G(0xf) |
                VIDISD14C_ALPHA1_B(0xf);
 
-       if (win->variant.has_osd_d) {
-               writel(data, regs + VIDOSD_D(win_no, sfb->variant));
-               writel(osdc_data, regs + VIDOSD_C(win_no, sfb->variant));
-       } else
-               writel(data, regs + VIDOSD_C(win_no, sfb->variant));
+       vidosd_set_alpha(win, alpha);
+       vidosd_set_size(win, data);
 
        data = WINCONx_ENWIN;
 
 static struct s3c_fb_win_variant s3c_fb_data_64xx_wins[] __devinitdata = {
        [0] = {
                .has_osd_c      = 1,
+               .osd_size_off   = 0x8,
                .palette_sz     = 256,
                .valid_bpp      = VALID_BPP1248 | VALID_BPP(16) | VALID_BPP(24),
        },
        [1] = {
                .has_osd_c      = 1,
                .has_osd_d      = 1,
+               .osd_size_off   = 0x12,
+               .has_osd_alpha  = 1,
                .palette_sz     = 256,
                .valid_bpp      = (VALID_BPP1248 | VALID_BPP(16) |
                                   VALID_BPP(18) | VALID_BPP(19) |
        [2] = {
                .has_osd_c      = 1,
                .has_osd_d      = 1,
+               .osd_size_off   = 0x12,
+               .has_osd_alpha  = 1,
                .palette_sz     = 16,
                .palette_16bpp  = 1,
                .valid_bpp      = (VALID_BPP1248 | VALID_BPP(16) |
        },
        [3] = {
                .has_osd_c      = 1,
+               .has_osd_alpha  = 1,
                .palette_sz     = 16,
                .palette_16bpp  = 1,
                .valid_bpp      = (VALID_BPP124  | VALID_BPP(16) |
        },
        [4] = {
                .has_osd_c      = 1,
+               .has_osd_alpha  = 1,
                .palette_sz     = 4,
                .palette_16bpp  = 1,
                .valid_bpp      = (VALID_BPP(1) | VALID_BPP(2) |
        },
        .win[1] = &(struct s3c_fb_win_variant) {
                .has_osd_c      = 1,
+               .has_osd_alpha  = 1,
                .palette_sz     = 256,
                .valid_bpp      = (VALID_BPP1248 | VALID_BPP(16) |
                                   VALID_BPP(18) | VALID_BPP(19) |