From dd4aae65f179458def8e21be6ad2d7b786aa345e Mon Sep 17 00:00:00 2001
From: Xin LI <delphij@FreeBSD.org>
Date: Fri, 20 May 2011 22:36:17 +0000
Subject: [PATCH] Add a new knob to atkbd(4) to enable typematic rate detection
 on boot, which is now disabled by default.  The detection is known to cause
 hangs on boot with some new Lenovo laptops on FreeBSD/amd64.

Reported by:	gnn
Discussed with:	jkim
MFC after:	3 months
---
 share/man/man4/atkbd.4    | 7 ++++++-
 sys/dev/atkbdc/atkbd.c    | 3 +++
 sys/dev/atkbdc/atkbdreg.h | 1 +
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/share/man/man4/atkbd.4 b/share/man/man4/atkbd.4
index 73831c2bb53..0c486e2eefb 100644
--- a/share/man/man4/atkbd.4
+++ b/share/man/man4/atkbd.4
@@ -26,7 +26,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 29, 2008
+.Dd May 20, 2011
 .Dt ATKBD 4
 .Os
 .Sh NAME
@@ -176,6 +176,11 @@ When this option is given, the
 .Nm
 driver will not test the keyboard port during the probe routine.
 Some machines hang during boot when this test is performed.
+.It bit 4 (PROBE_TYPEMATIC)
+When this option is given, the
+.Nm
+driver will try to probe the keyboard typematic rate on boot.
+Some machines hang during boot when this test is performed.
 .El
 .\".Sh FILES
 .Sh EXAMPLES
diff --git a/sys/dev/atkbdc/atkbd.c b/sys/dev/atkbdc/atkbd.c
index 600020fae6d..643554d1f4d 100644
--- a/sys/dev/atkbdc/atkbd.c
+++ b/sys/dev/atkbdc/atkbd.c
@@ -1097,6 +1097,9 @@ get_typematic(keyboard_t *kbd)
 	x86regs_t regs;
 	uint8_t *p;
 
+	if (!(kbd->kb_config & KB_CONF_PROBE_TYPEMATIC))
+		return (ENODEV);
+
 	if (x86bios_get_intr(0x15) == 0 || x86bios_get_intr(0x16) == 0)
 		return (ENODEV);
 
diff --git a/sys/dev/atkbdc/atkbdreg.h b/sys/dev/atkbdc/atkbdreg.h
index cf7ee6b3128..3d54b4d7022 100644
--- a/sys/dev/atkbdc/atkbdreg.h
+++ b/sys/dev/atkbdc/atkbdreg.h
@@ -36,6 +36,7 @@
 #define KB_CONF_NO_RESET	(1 << 1) /* don't reset the keyboard */
 #define KB_CONF_ALT_SCANCODESET	(1 << 2) /* assume the XT type keyboard */
 #define	KB_CONF_NO_PROBE_TEST	(1 << 3) /* don't test keyboard during probe */
+#define	KB_CONF_PROBE_TYPEMATIC	(1 << 4) /* probe keyboard typematic */
 
 #ifdef _KERNEL