[PATCH] video/udlfb: fix line counting in fb_write

[PATCH] video/udlfb: fix line counting in fb_write

[Alexander Holler]

Line 0 and 1 were both written to line 0 (on the display) and all subsequent
lines had an offset of -1. The result was that the last line on the display
was never overwritten by writes to /dev/fbN.

Signed-off-by: Alexander Holler <holler@ahsoftware.de>
---
 drivers/video/udlfb.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c
index a159b63..85d8110 100644
--- a/drivers/video/udlfb.c
+++ b/drivers/video/udlfb.c
@@ -647,7 +647,7 @@ static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
 	result = fb_sys_write(info, buf, count, ppos);
 
 	if (result > 0) {
-		int start = max((int)(offset / info->fix.line_length) - 1, 0);
+		int start = max((int)(offset / info->fix.line_length), 0);
 		int lines = min((u32)((result / info->fix.line_length) + 1),
 				(u32)info->var.yres);
 
-- 
1.7.6.5

Re: [PATCH] video/udlfb: fix line counting in fb_write

[Alexander Holler]

Hello,

sorry, I forgot to mention that this is a candidate for all stable trees 
2.6.37 and above. Not sure how to announce that, but I think I should 
have added the below Cc: to the patch.

Regards,

Alexander

Am 21.04.2012 00:10, schrieb Alexander Holler:
> Line 0 and 1 were both written to line 0 (on the display) and all subsequent
> lines had an offset of -1. The result was that the last line on the display
> was never overwritten by writes to /dev/fbN.
>
> Signed-off-by: Alexander Holler<holler@ahsoftware.de>

Cc: stable@vger.kernel.org

> ---
>   drivers/video/udlfb.c |    2 +-
>   1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c
> index a159b63..85d8110 100644
> --- a/drivers/video/udlfb.c
> +++ b/drivers/video/udlfb.c
> @@ -647,7 +647,7 @@ static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
>   	result = fb_sys_write(info, buf, count, ppos);
>
>   	if (result>  0) {
> -		int start = max((int)(offset / info->fix.line_length) - 1, 0);
> +		int start = max((int)(offset / info->fix.line_length), 0);
>   		int lines = min((u32)((result / info->fix.line_length) + 1),
>   				(u32)info->var.yres);
>