Re: [PATCH] Add new linearfb driver

On 08/25/2010 01:04 PM, Bruno Prémont wrote:

On Wed, 25 August 2010 Colin Watson [off-list ref] wrote:

quoted

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 <redacted>
Acked-by: Matthew Garrett <redacted>
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

        ^^^^^^^^^^^^^^^^^^^^^^^

quoted

 	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.

This could also be solved by just making it depend on FB_LINEAR instead of
using "select".

-- 
        Peter

I number the Linux folks among my personal heroes.
		-- Donald Knuth

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