[PATCH] fb: update cdev map_base

[Sascha Hauer]

On Fri, Jan 14, 2011 at 08:48:44PM +0100, Sascha Hauer wrote:
> Calling fb_activate_var potentially changes the framebuffer address,
> so we have to update the fb0 cdev afterwards.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  drivers/video/fb.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/video/fb.c b/drivers/video/fb.c
> index aad0e1f..ba34b9c 100644
> --- a/drivers/video/fb.c
> +++ b/drivers/video/fb.c
> @@ -79,6 +79,8 @@ static int fb_setup_mode(struct device_d *dev, struct param_d *param,
>  
>  	ret = info->fbops->fb_activate_var(info);
>  
> +	dev->map_base = (unsigned long)info->screen_base;
> +
>  	if (ret == 0)
>  		dev_param_set_generic(dev, param, val);
>  


Unfortunately this is not enough. We also have to update xres, yres and
size, like in the following patch:

8<------------------------------------------------

[PATCH 5/5] fb: When setting a mode, also update xres, yres and fb size

Also, set size to 0 when setting up the framebuffer failed so that
the user cannot write to uninitialized framebuffer memory.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 drivers/video/fb.c |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/video/fb.c b/drivers/video/fb.c
index ba34b9c..cf21c4b 100644
--- a/drivers/video/fb.c
+++ b/drivers/video/fb.c
@@ -77,12 +77,18 @@ static int fb_setup_mode(struct device_d *dev, struct param_d *param,
 
 	info->mode = &info->mode_list[mode];
 
-	ret = info->fbops->fb_activate_var(info);
+	info->xres = info->mode->xres;
+	info->yres = info->mode->yres;
 
-	dev->map_base = (unsigned long)info->screen_base;
+	ret = info->fbops->fb_activate_var(info);
 
-	if (ret == 0)
+	if (!ret) {
+		dev->map_base = (unsigned long)info->screen_base;
+		info->cdev.size = info->xres * info->yres * (info->bits_per_pixel >> 3);
+		dev->size = info->cdev.size;
 		dev_param_set_generic(dev, param, val);
+	} else
+		info->cdev.size = 0;
 
 	return ret;
 }
-- 
1.7.2.3

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