[PATCH] fbdev: Firmware EDID fixes

- make firmware edid independent from framebuffer (No need to choose
  framebuffer just to disable this option

- enable this option in X86_64

- check if VBE/DDC function is implemented before calling actual function

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

5 files changed, 54 insertions, 18 deletions

diff --git a/arch/i386/boot/video.S b/arch/i386/boot/video.S
index c9343c3a8082..8c2a6faeeae5 100644
--- a/arch/i386/boot/video.S
+++ b/arch/i386/boot/video.S
@@ -1929,7 +1929,7 @@ skip10:	movb	%ah, %al
 	ret
 
 store_edid:
-#ifdef CONFIG_FB_FIRMWARE_EDID
+#ifdef CONFIG_FIRMWARE_EDID
 	pushw	%es				# just save all registers
 	pushw	%ax
 	pushw	%bx
@@ -1947,6 +1947,22 @@ store_edid:
 	rep
 	stosl
 
+	pushw   %es				# save ES
+	xorw    %di, %di                        # Report Capability
+	pushw   %di
+	popw    %es                             # ES:DI must be 0:0
+	movw	$0x4f15, %ax
+	xorw	%bx, %bx
+	xorw	%cx, %cx
+	int	$0x10
+	popw    %es                             # restore ES
+
+	cmpb    $0x00, %ah                      # call successful
+	jne     no_edid
+
+	cmpb    $0x4f, %al                      # function supported
+	jne     no_edid
+
 	movw	$0x4f15, %ax                    # do VBE/DDC
 	movw	$0x01, %bx
 	movw	$0x00, %cx
@@ -1954,6 +1970,7 @@ store_edid:
 	movw	$0x140, %di
 	int	$0x10
 
+no_edid:
 	popw	%di				# restore all registers
 	popw	%dx
 	popw	%cx
diff --git a/arch/x86_64/boot/video.S b/arch/x86_64/boot/video.S
index 32327bb37aff..2aa565c136e5 100644
--- a/arch/x86_64/boot/video.S
+++ b/arch/x86_64/boot/video.S
@@ -1929,6 +1929,7 @@ skip10:	movb	%ah, %al
 	ret
 
 store_edid:
+#ifdef CONFIG_FIRMWARE_EDID
 	pushw	%es				# just save all registers
 	pushw	%ax
 	pushw	%bx
@@ -1946,6 +1947,22 @@ store_edid:
 	rep
 	stosl
 
+	pushw   %es				# save ES
+	xorw    %di, %di                        # Report Capability
+	pushw   %di
+	popw    %es                             # ES:DI must be 0:0
+	movw	$0x4f15, %ax
+	xorw	%bx, %bx
+	xorw	%cx, %cx
+	int	$0x10
+	popw    %es                             # restore ES
+
+	cmpb    $0x00, %ah                      # call successful
+	jne     no_edid
+
+	cmpb    $0x4f, %al                      # function supported
+	jne     no_edid
+
 	movw	$0x4f15, %ax                    # do VBE/DDC
 	movw	$0x01, %bx
 	movw	$0x00, %cx
@@ -1953,12 +1970,14 @@ store_edid:
 	movw	$0x140, %di
 	int	$0x10
 
+no_edid:
 	popw	%di				# restore all registers
 	popw	%dx
 	popw	%cx
 	popw	%bx
 	popw	%ax
 	popw	%es
+#endif
 	ret
 
 # VIDEO_SELECT-only variables
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index fb850b52b4da..143c65031539 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -109,6 +109,7 @@ struct sys_desc_table_struct {
 };
 
 struct edid_info edid_info;
+EXPORT_SYMBOL_GPL(edid_info);
 struct e820map e820;
 
 extern int root_mountflags;
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 90cd5587d4e3..2a265e1c7cbc 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -4,6 +4,21 @@
 
 menu "Graphics support"
 
+config FIRMWARE_EDID
+       bool "Enable firmware EDID"
+       default y
+       ---help---
+         This enables access to the EDID transferred from the firmware.
+	 On the i386, this is from the Video BIOS. Enable this if DDC/I2C
+	 transfers do not work for your driver and if you are using
+	 nvidiafb, i810fb or savagefb.
+
+	 In general, choosing Y for this option is safe.  If you
+	 experience extremely long delays while booting before you get
+	 something on your display, try setting this to N.  Matrox cards in
+	 combination with certain motherboards and monitors are known to
+	 suffer from this problem.
+
 config FB
 	tristate "Support for frame buffer devices"
 	---help---
@@ -70,22 +85,6 @@ config FB_MACMODES
        depends on FB
        default n
 
-config FB_FIRMWARE_EDID
-       bool "Enable firmware EDID"
-       depends on FB
-       default y
-       ---help---
-         This enables access to the EDID transferred from the firmware.
-	 On the i386, this is from the Video BIOS. Enable this if DDC/I2C
-	 transfers do not work for your driver and if you are using
-	 nvidiafb, i810fb or savagefb.
-
-	 In general, choosing Y for this option is safe.  If you
-	 experience extremely long delays while booting before you get
-	 something on your display, try setting this to N.  Matrox cards in
-	 combination with certain motherboards and monitors are known to
-	 suffer from this problem.
-
 config FB_BACKLIGHT
        bool
        depends on FB
diff --git a/drivers/video/fbmon.c b/drivers/video/fbmon.c
index 87b0224d2347..3ccfff715a51 100644
--- a/drivers/video/fbmon.c
+++ b/drivers/video/fbmon.c
@@ -1301,7 +1301,7 @@ int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
 		-EINVAL : 0;
 }
 
-#if defined(CONFIG_FB_FIRMWARE_EDID) && defined(__i386__)
+#if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
 
 /*
  * We need to ensure that the EDID block is only returned for