Re: [RFC][PATCH] "Disable Trackpad while typing" on Notebooks withh a PS/2 Trackpad

Hans-Georg Thien
2003-05-05T22:33:35Z

Hans-Georg Thien <1682-600@onlinehome.de> writes:

> The short story
> ---------------
> Apple MacIntosh iBook Notebooks computers have a nice feature that
> prevents unintended trackpad input while typing on the keyboard. There
> are no mouse-moves or mouse-taps for a short period of time after each
> keystroke. I wanted to have this feature on my i386 notebook ...

I have eliminated the use of a timer. The patch has been simple before,
and now it is even more simple :)

diff -urN -X /tmp/dontdiff
/usr/src/linux-2.4.20/Documentation/Configure.help
/usr/src/linux/Documentation/Configure.help
--- /usr/src/linux-2.4.20/Documentation/Configure.help Fri Nov 29
00:53:08 2002
+++ /usr/src/linux/Documentation/Configure.help Thu May 1 02:12:04 2003
@@ -17752,6 +17752,16 @@
<ftp://gnu.systemy.it/pub/gpm/>) solves this problem, or you can get
the "mconv2" utility from <ftp://ibiblio.org/pub/Linux/system/mouse/>.

+Disable trackpad while typing
+CONFIG_DISABLE_TRACKPAD_WHILE_TYPING
+ For people with a notebook that have a build in PS/2 trackpad.
+
+ It prevents unintended mouse moves and mouse taps while typing on
+ the notebook keyboard.
+
+ The majority of notebooks on the market have a PS/2 trackpad.
+ So you will probably say "Y" if you have a notebook with a trackpad.
+
C&T 82C710 mouse port support (as on TI Travelmate)
CONFIG_82C710_MOUSE
This is a certain kind of PS/2 mouse used on the TI Travelmate. If
diff -urN -X /tmp/dontdiff /usr/src/linux-2.4.20/drivers/char/Config.in
/usr/src/linux/drivers/char/Config.in
--- /usr/src/linux-2.4.20/drivers/char/Config.in Fri Nov 29 00:53:12 2002
+++ /usr/src/linux/drivers/char/Config.in Thu May 1 02:30:45 2003
@@ -170,6 +170,13 @@
tristate 'Mouse Support (not serial and bus mice)' CONFIG_MOUSE
if [ "$CONFIG_MOUSE" != "n" ]; then
bool ' PS/2 mouse (aka "auxiliary device") support' CONFIG_PSMOUSE
+
+ if [ "$CONFIG_PSMOUSE" = "y" ]
+ then
+ bool ' Disable Trackpad while typing on Notebooks'
CONFIG_DISABLE_TRACKPAD_WHILE_TYPING
+ fi
+
+
tristate ' C&T 82C710 mouse port support (as on TI Travelmate)'
CONFIG_82C710_MOUSE
tristate ' PC110 digitizer pad support' CONFIG_PC110_PAD
tristate ' MK712 touch screen support' CONFIG_MK712_MOUSE
diff -urN -X /tmp/dontdiff /usr/src/linux-2.4.20/drivers/char/pc_keyb.c
/usr/src/linux/drivers/char/pc_keyb.c
--- /usr/src/linux-2.4.20/drivers/char/pc_keyb.c Fri Nov 29 00:53:12 2002
+++ /usr/src/linux/drivers/char/pc_keyb.c Tue May 6 02:07:27 2003
@@ -13,6 +13,11 @@
* Code fixes to handle mouse ACKs properly.
* C. Scott Ananian <cananian@alumni.princeton.edu> 1999-01-29.
*
+ * Implemented the "disable trackpad while typing" feature. This prevents
+ * unintended mouse moves and mouse taps while typing on the keyboard on
+ * notebooks with a PS/2 trackpad.
+ * Hans-Georg Thien <1682-600@onlinehome.de> 2003-04-30.
+ *
*/

#include <linux/config.h>
@@ -67,6 +72,11 @@
static void aux_write_ack(int val);
static void __aux_write_ack(int val);
static int aux_reconnect = 0;
+
+#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING
+static int last_kbd_event = 0; /* used to hold timestamp of last kbd
event */
+#endif
+
#endif

#ifndef kbd_controller_present
@@ -430,6 +440,7 @@
}

+
static inline void handle_mouse_event(unsigned char scancode)
{
#ifdef CONFIG_PSMOUSE
@@ -449,6 +460,11 @@
return;
}

+#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING
+ /* do nothing if time since last kbd event is less then 1Sec */
+ if ( abs(jiffies - last_kbd_event) < HZ ) return;
+#endif
+
prev_code = scancode;
add_mouse_randomness(scancode);
if (aux_count) {
@@ -467,8 +483,14 @@

static unsigned char kbd_exists = 1;

+
static inline void handle_keyboard_event(unsigned char scancode)
{
+
+#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING
+ last_kbd_event = jiffies;
+#endif
+
#ifdef CONFIG_VT
kbd_exists = 1;
if (do_acknowledge(scancode))