Re: [PATCH] ARM: video: mxs: Fix mxsfb misconfiguring VDCTRL0

[Greg KH <greg@kroah.com>]

On Mon, Mar 18, 2013 at 07:23:17PM +0100, Marek Vasut wrote:
> The issue fixed by this patch manifests only then using X11
> with mxsfb driver. The X11 will display either shifted image
> or otherwise distorted image on the LCD.
> 
> The problem is that the X11 tries to reconfigure the framebuffer
> and along the way calls fb_ops.fb_set_par() with X11's desired
> configuration values. The field of particular interest is
> fb_info->var.sync which contains non-standard values if
> configured by kernel. These are either FB_SYNC_DATA_ENABLE_HIGH_ACT,
> FB_SYNC_DOTCLK_FAILING_ACT or both, depending on the platform
> configuration. Both of these values are defined in the
> include/linux/mxsfb.h file.
> 
> The driver interprets these values and configures the LCD controller
> accordingly. Yet X11 only has access to the standard values for this
> field defined in include/uapi/linux/fb.h and thus, unlike kernel,
> omits these special values. This results in distorted image on the
> LCD.
> 
> This patch moves these non-standard values into new field of the
> mxsfb_platform_data structure so the driver can in turn check this
> field instead of the video mode field for these specific portions.
> 
> Moreover, this patch prefixes these values with MXSFB_SYNC_ prefix
> instead of FB_SYNC_ prefix to prevent confusion of subsequent users.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Fabio Estevam <fabio.estevam@freescale.com>
> Cc: Linux ARM <linux-arm-kernel@lists.infradead.org>
> Cc: Linux FBDEV <linux-fbdev@vger.kernel.org>
> Cc: Lothar Waßmann <LW@karo-electronics.de>
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
> ---
>  arch/arm/mach-mxs/mach-mxs.c |   22 +++++++++++-----------
>  drivers/video/mxsfb.c        |    7 +++++--
>  include/linux/mxsfb.h        |    7 +++++--
>  3 files changed, 21 insertions(+), 15 deletions(-)
> 
> NOTE: This is the version for stable v3.8.3, so I'm sending it to -stable.
>       I will send adjusted version for mainline 3.9-rc , since there is
>       one more board in mainline and therefore the versions of the patch
>       must differ.


<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read Documentation/stable_kernel_rules.txt
for how to do this properly.

</formletter>