Re: [BUGFIX] video/mxsfb: fix crash when unblanking the display

From: Lothar WaÃmann
Date: Wed Dec 21 2011 - 02:27:20 EST


Hi,

Lothar WaÃmann writes:
> 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 WaÃmann <LW@xxxxxxxxxxxxxxxxxxx>
> ---
> 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 d837d63..03cb95a 100644
> --- a/drivers/video/mxsfb.c
> +++ b/drivers/video/mxsfb.c
> @@ -366,7 +366,8 @@ 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(host->clk);
>
> --
> 1.5.6.5
>
Ping. Any comments on this?


Lothar WaÃmann
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