OMAP3630: DSS2: Enable Pre-Multiplied Alpha Support

Enable dss to process color formats with pre-mulitplied alpha.
With this we can have alpha values defined for each pixel
and hence can have different blending values for each pixel.
sysfs entry has been created for this and pre-multiplied alpha
support is turned off by default.

Signed-off-by: Sudeep Basavaraj <sudeep.basavaraj@ti.com>
Signed-off-by: Rajkumar N <rajkumar.nagarajan@ti.com>
Signed-off-by: Samreen <samreen@ti.com>
Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
diff --git a/drivers/video/omap2/dss/overlay.c b/drivers/video/omap2/dss/overlay.c
index 75642c2..41a2902 100644
--- a/drivers/video/omap2/dss/overlay.c
+++ b/drivers/video/omap2/dss/overlay.c
@@ -257,6 +257,43 @@
 	return size;
 }
 
+static ssize_t overlay_pre_mult_alpha_show(struct omap_overlay *ovl,
+		char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "%d\n",
+			ovl->info.pre_mult_alpha);
+}
+
+static ssize_t overlay_pre_mult_alpha_store(struct omap_overlay *ovl,
+		const char *buf, size_t size)
+{
+	int r;
+	struct omap_overlay_info info;
+
+	ovl->get_overlay_info(ovl, &info);
+
+	/* only GFX and Video2 plane support pre alpha multiplied
+	 * set zero for Video1 plane
+	 */
+	if (!dss_has_feature(FEAT_GLOBAL_ALPHA_VID1) &&
+		ovl->id == OMAP_DSS_VIDEO1)
+		info.pre_mult_alpha = 0;
+	else
+		info.pre_mult_alpha = simple_strtoul(buf, NULL, 10);
+
+	r = ovl->set_overlay_info(ovl, &info);
+	if (r)
+		return r;
+
+	if (ovl->manager) {
+		r = ovl->manager->apply(ovl->manager);
+		if (r)
+			return r;
+	}
+
+	return size;
+}
+
 struct overlay_attribute {
 	struct attribute attr;
 	ssize_t (*show)(struct omap_overlay *, char *);
@@ -280,6 +317,9 @@
 		overlay_enabled_show, overlay_enabled_store);
 static OVERLAY_ATTR(global_alpha, S_IRUGO|S_IWUSR,
 		overlay_global_alpha_show, overlay_global_alpha_store);
+static OVERLAY_ATTR(pre_mult_alpha, S_IRUGO|S_IWUSR,
+		overlay_pre_mult_alpha_show,
+		overlay_pre_mult_alpha_store);
 
 static struct attribute *overlay_sysfs_attrs[] = {
 	&overlay_attr_name.attr,
@@ -290,6 +330,7 @@
 	&overlay_attr_output_size.attr,
 	&overlay_attr_enabled.attr,
 	&overlay_attr_global_alpha.attr,
+	&overlay_attr_pre_mult_alpha.attr,
 	NULL
 };