From 4a78789776f879eb9eeec10d1768aaa0143d5974 Mon Sep 17 00:00:00 2001
From: Liu Ying <Ying.Liu@freescale.com>
Date: Mon, 11 Jun 2012 09:06:50 +0800
Subject: [PATCH] --- yaml --- r: 321021 b: refs/heads/master c:
 41a490ec019fd172f5d0356e01d8101b4708aee2 h: refs/heads/master i:   321019:
 f3a6530d8cd6e3f2ab605282adff5e1140c626b6 v: v3

---
 [refs]                      |  2 +-
 trunk/drivers/video/mx3fb.c | 22 +++++++++++++++++++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 5aaf588eb06f..a97d50c5759f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6cd77e00c00c5da3b6f8546dcb6dfac9611ca10b
+refs/heads/master: 41a490ec019fd172f5d0356e01d8101b4708aee2
diff --git a/trunk/drivers/video/mx3fb.c b/trunk/drivers/video/mx3fb.c
index da1d052a18a5..c89f8a8d36d2 100644
--- a/trunk/drivers/video/mx3fb.c
+++ b/trunk/drivers/video/mx3fb.c
@@ -698,6 +698,26 @@ static void mx3fb_dma_done(void *arg)
 	complete(&mx3_fbi->flip_cmpl);
 }
 
+static bool mx3fb_must_set_par(struct fb_info *fbi)
+{
+	struct mx3fb_info *mx3_fbi = fbi->par;
+	struct fb_var_screeninfo old_var = mx3_fbi->cur_var;
+	struct fb_var_screeninfo new_var = fbi->var;
+
+	if ((fbi->var.activate & FB_ACTIVATE_FORCE) &&
+	    (fbi->var.activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW)
+		return true;
+
+	/*
+	 * Ignore xoffset and yoffset update,
+	 * because pan display handles this case.
+	 */
+	old_var.xoffset = new_var.xoffset;
+	old_var.yoffset = new_var.yoffset;
+
+	return !!memcmp(&old_var, &new_var, sizeof(struct fb_var_screeninfo));
+}
+
 static int __set_par(struct fb_info *fbi, bool lock)
 {
 	u32 mem_len, cur_xoffset, cur_yoffset;
@@ -819,7 +839,7 @@ static int mx3fb_set_par(struct fb_info *fbi)
 
 	mutex_lock(&mx3_fbi->mutex);
 
-	ret = __set_par(fbi, true);
+	ret = mx3fb_must_set_par(fbi) ? __set_par(fbi, true) : 0;
 
 	mutex_unlock(&mx3_fbi->mutex);