Re: [PATCH] Add new linearfb driver

["Bruno Prémont" <bonbons@linux-vserver.org>]

On Wed, 25 August 2010 Colin Watson <cjwatson@canonical.com> wrote:
> Split out linearfb from efifb so that boot loaders can program it as a
> simple linear framebuffer on non-EFI systems.  This is useful for boot
> loaders with their own graphics drivers, e.g. GRUB 2, since in some
> cases on x86 they can set up non-VESA modes and thus can't program
> vesafb.
> 
> efifb is reworked on top of this common code, and it should be possible
> to do the same with some other framebuffer drivers in future.
> 
> Signed-off-by: Colin Watson <cjwatson@canonical.com>
> Acked-by: Matthew Garrett <mjg@redhat.com>
> Cc: Peter Jones <pjones@redhat.com>
> ---
>  drivers/video/Kconfig       |   17 ++-
>  drivers/video/Makefile      |    1 +
>  drivers/video/efifb.c       |  222 +----------------------------
>  drivers/video/linearfb.c    |  332 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/fb.h          |    8 +
>  include/linux/screen_info.h |    2 +
>  6 files changed, 364 insertions(+), 218 deletions(-)
>  create mode 100644 drivers/video/linearfb.c
> 
> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
> index 59c51d9..a7735ec 100644
> --- a/drivers/video/Kconfig
> +++ b/drivers/video/Kconfig
> @@ -721,13 +721,24 @@ config FB_VESA
>  	  You will get a boot time penguin logo at no additional cost. Please
>  	  read <file:Documentation/fb/vesafb.txt>. If unsure, say Y.
>  
> -config FB_EFI
> -	bool "EFI-based Framebuffer Support"
> -	depends on (FB = y) && X86 && EFI
> +config FB_LINEAR
> +	bool "Simple linear framebuffer support"
> +	depends on FB
>  	select FB_CFB_FILLRECT
>  	select FB_CFB_COPYAREA
>  	select FB_CFB_IMAGEBLIT
        ^^^^^^^^^^^^^^^^^^^^^^^

>  	help
> +	  This is a simple linear frame buffer device driver. It has no
> +	  hardware-specific programming capability, but must be programmed
> +	  by the boot loader or by another frame buffer driver.
> +
> +	  If unsure, say N.
> +
> +config FB_EFI
> +	bool "EFI-based Framebuffer Support"
> +	depends on (FB = y) && X86 && EFI
> +	select FB_LINEAR
        ^^^^^^^^^^^^^^^^
  Has kconfig been adjusted to process select recursively?
  If not the selects from FB_LINEAR will have to be copied here.

  Bruno


> +	help
>  	  This is the EFI frame buffer device driver. If the firmware on
>  	  your platform is EFI 1.10 or UEFI 2.0, select Y to add support for
>  	  using the EFI framebuffer as your console.
> diff --git a/drivers/video/Makefile b/drivers/video/Makefile
> index ddc2af2..ad74d3b 100644