[BUGFIX PATCH] video: mxsfb: fix crash when unblanking the display
LW at KARO-electronics.de
Thu Nov 22 07:49:14 EST 2012
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.
Note: I already sent this patch in December 2011 but noone picked it up obviously.
Signed-off-by: Lothar Waßmann <LW at KARO-electronics.de>
drivers/video/mxsfb.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index 49619b4..f2a49ef 100644
@@ -369,7 +369,8 @@ static void mxsfb_disable_controller(struct fb_info *fb_info)
- 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);
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