From a34bfbf421c069da5ea2f7a1d0f337b78e345039 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Lothar=20Wa=C3=9Fmann?= Date: Thu, 22 Nov 2012 13:49:14 +0100 Subject: [PATCH] video: mxsfb: fix crash when unblanking the display MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit commit 6c1ecba8d84841277d68140ef485335d5be28485 upstream. The VDCTRL4 register does not provide the MXS SET/CLR/TOGGLE feature. The write in mxsfb_disable_controller() sets the data_cnt for the LCD DMA to 0 which obviously means the max. count for the LCD DMA and leads to overwriting arbitrary memory when the display is unblanked. Signed-off-by: Lothar Waßmann Acked-by: Juergen Beisert Tested-by: Lauri Hintsala Signed-off-by: Shawn Guo Signed-off-by: Greg Kroah-Hartman --- drivers/video/mxsfb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c index 49619b441500..f2a49ef772f3 100644 --- a/drivers/video/mxsfb.c +++ b/drivers/video/mxsfb.c @@ -369,7 +369,8 @@ static void mxsfb_disable_controller(struct fb_info *fb_info) loop--; } - writel(VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4 + REG_CLR); + reg = readl(host->base + LCDC_VDCTRL4); + writel(reg & ~VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4); clk_disable_unprepare(host->clk); -- 2.39.5