The patch titled

     fix reboot via keyboard controller reset

has been added to the -mm tree.  Its filename is

     fix-reboot-via-keyboard-controller-reset.patch

Patches currently in -mm which might be from [EMAIL PROTECTED] are

fix-reboot-via-keyboard-controller-reset.patch



From: Truxton Fulton <[EMAIL PROTECTED]>

I have a system (Biostar IDEQ210M mini-pc with a VIA chipset) which will
not reboot unless a keyboard is plugged in to it.  I have tried all
combinations of the kernel "reboot=x,y" flags to no avail.  Rebooting by
any method will leave the system in a wedged state (at the "Restarting
system" message).

I finally tracked the problem down to the machine's refusal to fully reboot
unless the keyboard controller status register had bit 2 set.  This is the
"System flag" which when set, indicates successful completion of the
keyboard controller self-test (Basic Assurance Test, BAT).

I suppose that something is trying to protect against sporadic reboots
unless the keyboard controller is in a good state (a keyboard is present),
but I need this machine to be headless.

I found that setting the system flag (via the command byte) before giving
the "pulse reset line" command will allow the reboot to proceed.  The patch
is simple, and I think it should be fine for everybody whether they have
this type of machine or not.  This affects the "hard" reboot (as done when
the kernel boot flags "reboot=c,h" are used).

Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 include/asm-i386/mach-default/mach_reboot.h |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletion(-)

diff -puN 
include/asm-i386/mach-default/mach_reboot.h~fix-reboot-via-keyboard-controller-reset
 include/asm-i386/mach-default/mach_reboot.h
--- 
25/include/asm-i386/mach-default/mach_reboot.h~fix-reboot-via-keyboard-controller-reset
     Mon Aug 29 13:53:35 2005
+++ 25-akpm/include/asm-i386/mach-default/mach_reboot.h Mon Aug 29 13:53:53 2005
@@ -22,7 +22,15 @@ static inline void mach_reboot(void)
        for (i = 0; i < 100; i++) {
                kb_wait();
                udelay(50);
-               outb(0xfe, 0x64);         /* pulse reset low */
+               outb(0x60, 0x64);       /* write Controller Command Byte */
+               udelay(50);
+               kb_wait();
+               udelay(50);
+               outb(0x14, 0x60);       /* set "System flag" */
+               udelay(50);
+               kb_wait();
+               udelay(50);
+               outb(0xfe, 0x64);       /* pulse reset low */
                udelay(50);
        }
 }
_
-
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