[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>
diff --git a/arch/i386/boot/video.S b/arch/i386/boot/video.S
index c9343c3..8c2a6fa 100644
--- a/arch/i386/boot/video.S
+++ b/arch/i386/boot/video.S
@@ -1929,7 +1929,7 @@
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 @@
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 @@
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 32327bb..2aa565c 100644
--- a/arch/x86_64/boot/video.S
+++ b/arch/x86_64/boot/video.S
@@ -1929,6 +1929,7 @@
ret
store_edid:
+#ifdef CONFIG_FIRMWARE_EDID
pushw %es # just save all registers
pushw %ax
pushw %bx
@@ -1946,6 +1947,22 @@
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 @@
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 fb850b5..143c650 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -109,6 +109,7 @@
};
struct edid_info edid_info;
+EXPORT_SYMBOL_GPL(edid_info);
struct e820map e820;
extern int root_mountflags;