From: Vincent Abriou <vincent.abriou@st.com>
Date: Thu, 2 Feb 2017 08:49:02 +0000 (+0100)
Subject: drm/sti: do not set gdp pixel clock rate if mode is not set
X-Git-Tag: v4.11-rc1~83^2~18^2~4
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=c5649ee49761f5367c46c5ae6579ab8e8b03575d;p=linux.git

drm/sti: do not set gdp pixel clock rate if mode is not set

Fix a division by 0 case : in some cases, when the GDP plane is being
disabled atomic_check() is called with "mode->clock = 0".
In that case, do not set parent and pixel clock rate.

Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
---

diff --git a/drivers/gpu/drm/sti/sti_gdp.c b/drivers/gpu/drm/sti/sti_gdp.c
index 7255234670c0..7f6d0790cca6 100644
--- a/drivers/gpu/drm/sti/sti_gdp.c
+++ b/drivers/gpu/drm/sti/sti_gdp.c
@@ -648,7 +648,7 @@ static int sti_gdp_atomic_check(struct drm_plane *drm_plane,
 	}
 
 	/* Set gdp clock */
-	if (gdp->clk_pix) {
+	if (mode->clock && gdp->clk_pix) {
 		struct clk *clkp;
 		int rate = mode->clock * 1000;
 		int res;