video: s3c-fb: add alpha value width setting

This patch adds alpha value width setting according to
transparency value of each window format, using BLENDCON
register. When alpha value is 8 bits, BLENDCON will set
alpha value width as 8 bits.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c
index 389189a9e775..9af6c1849c24 100644
--- a/drivers/video/s3c-fb.c
+++ b/drivers/video/s3c-fb.c
@@ -82,6 +82,7 @@ struct s3c_fb;
  * @palette: Address of palette memory, or 0 if none.
  * @has_prtcon: Set if has PRTCON register.
  * @has_shadowcon: Set if has SHADOWCON register.
+ * @has_blendcon: Set if has BLENDCON register.
  * @has_clksel: Set if VIDCON0 register has CLKSEL bit.
  */
 struct s3c_fb_variant {
@@ -100,6 +101,7 @@ struct s3c_fb_variant {
 
         unsigned int    has_prtcon:1;
         unsigned int    has_shadowcon:1;
+        unsigned int    has_blendcon:1;
         unsigned int    has_clksel:1;
 };
 
@@ -691,6 +693,17 @@ static int s3c_fb_set_par(struct fb_info *info)
         writel(data, regs + sfb->variant.wincon + (win_no * 4));
         writel(0x0, regs + sfb->variant.winmap + (win_no * 4));
 
+        /* Set alpha value width */
+        if (sfb->variant.has_blendcon) {
+                data = readl(sfb->regs + BLENDCON);
+                data &= ~BLENDCON_NEW_MASK;
+                if (var->transp.length > 4)
+                        data |= BLENDCON_NEW_8BIT_ALPHA_VALUE;
+                else
+                        data |= BLENDCON_NEW_4BIT_ALPHA_VALUE;
+                writel(data, sfb->regs + BLENDCON);
+        }
+
         shadow_protect_win(win, 0);
 
         pm_runtime_put_sync(sfb->dev);
@@ -1798,6 +1811,7 @@ static struct s3c_fb_driverdata s3c_fb_data_s5pc100 = {
                 },
 
                 .has_prtcon     = 1,
+                .has_blendcon   = 1,
                 .has_clksel     = 1,
         },
         .win[0] = &s3c_fb_data_s5p_wins[0],
@@ -1829,6 +1843,7 @@ static struct s3c_fb_driverdata s3c_fb_data_s5pv210 = {
                 },
 
                 .has_shadowcon  = 1,
+                .has_blendcon   = 1,
                 .has_clksel     = 1,
         },
         .win[0] = &s3c_fb_data_s5p_wins[0],
@@ -1860,6 +1875,7 @@ static struct s3c_fb_driverdata s3c_fb_data_exynos4 = {
                 },
 
                 .has_shadowcon  = 1,
+                .has_blendcon   = 1,
         },
         .win[0] = &s3c_fb_data_s5p_wins[0],
         .win[1] = &s3c_fb_data_s5p_wins[1],
@@ -1923,6 +1939,8 @@ static struct s3c_fb_driverdata s3c_fb_data_s5p64x0 = {
                         [1] = 0x2800,
                         [2] = 0x2c00,
                 },
+
+                .has_blendcon   = 1,
         },
         .win[0] = &s3c_fb_data_s5p_wins[0],
         .win[1] = &s3c_fb_data_s5p_wins[1],