Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262624AbTEAVdz (ORCPT ); Thu, 1 May 2003 17:33:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262700AbTEAVdz (ORCPT ); Thu, 1 May 2003 17:33:55 -0400 Received: from moutng.kundenserver.de ([212.227.126.171]:12014 "EHLO moutng.kundenserver.de") by vger.kernel.org with ESMTP id S262624AbTEAVdu (ORCPT ); Thu, 1 May 2003 17:33:50 -0400 Message-ID: <3EB19625.6040904@onlinehome.de> Date: Thu, 01 May 2003 23:48:21 +0200 From: Hans-Georg Thien <1682-600@onlinehome.de> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.3) Gecko/20030312 X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: [RFC][PATCH] "Disable Trackpad while typing" on Notebooks withh a PS/2 Trackpad Content-Type: multipart/mixed; boundary="------------040904010309040302080300" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8397 Lines: 240 This is a multi-part message in MIME format. --------------040904010309040302080300 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sorry for this long text and my bad english. And please be kind to me - it is my very first posting to this mailing list ... I have written a *very small* patch against the linux 2.4.20 kernel and I want to submit it now. The short story --------------- The trackpad on the MacIntosh iBook Notebooks have a 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 believe that many people with i386 notebooks would like this feature and I want to give it to the linux community. First I had the idea of writing a loadable kernel module "trackpad" that implements that feature and is loadable via insmod keybd_irq=? mouse_irq=? delay=? The long story -------------- My first approach was - because I came from the bad old M$-DOS times - write something like a "terminate and stay resident program" Procedure LoadModule Save the currentlly installed handlers for keyboard and mouse. Install your own interrupt handlers for keyboard and mouse. End Procedure UnloadModule Stop and remove "reset-timer" if necessary Restore the saved interrupt handlers for keyboard and mouse End Procedure KbdHandler Stop or modify "reset-timer" if necessary Set global variable block_mouse_events=1 Start a timer that resets block_mouse_events=0 after ??? mSec Call the old keyboard interrupt handler End Proceure MouseHandler if block_mouse_events>0 then call ACK(mouse irq) if necessary do nothing else call old mouse interrupt handler End So I bought the book "Linux Device Drivers" written by Alessandro Rubini & Jonathan Corbert. It is an excellent book about LKM, but I couldn't find a way to "save and restore" irq-handlers as in the design described above. That's why I requested a little help in the newsgroup at comp.os.linux.development.system. This ended up with some people who said "don't mess around with irq-handlers in that way". While trying to gain a deeper understanding of irq-handling - espically for mouse and keyboard handlers - I found out that the keyboard and mouse interrupts are handled *both* in /usr/src/linux/drivers/char/pc_keyb.c. Ok, that is only true for PS/2 mice, but the majority of notebooks on the market have a PS/2 trackpad. On modifiying the pc_keyb.c file there is no longer a need to save/restore Interrupt handlers or to call them indirecty via a function pointer. Unfortunatly it has to be compiled in the kernel and cannot be written as a LKM module. But anyway - I sad down and got a working solution very quickly! I'm very glad with it! I needed not more than 45 minutes to get this working! Works in textmode (gpm) and under X11 as expected! Testing ------- I have tested my patch only on my own notebook (Compaq M300). It would help a lot if there are some volunteers... Future Plans ------------ [x] make the "disable trackpad time" configurable via the /proc filesystem. Do you think that /proc/sys/kernel/trackpad is a good place for it? There are other files under the /proc/sys/kernel directory that fall in the category "keyboard handling", e.g. ctrl-alt-del or sysrq. [x] make a /proc entry to allow "disable trackpad" and "enable trackpad". That would allow to turn the builtin trackpad off when an external mouse is pluged in, and to re-enable it when an external mouse is unplugged again. Here is the patch ----------------- --------------040904010309040302080300 Content-Type: text/plain; name="trackpad_patch.diff" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="trackpad_patch.diff" diff -urN -X /tmp/dontdiff linux-2.4.20/Documentation/Configure.help /usr/src/linux/Documentation/Configure.help --- 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 @@ ) solves this problem, or you can get the "mconv2" utility from . +Disable trackpad while typing +CONFIG_DISABLE_TRACKPAD_WHILE_TYPING + For people with a notebook that have a build in 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 linux-2.4.20/drivers/char/Config.in /usr/src/linux/drivers/char/Config.in --- 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 linux-2.4.20/drivers/char/pc_keyb.c /usr/src/linux/drivers/char/pc_keyb.c --- linux-2.4.20/drivers/char/pc_keyb.c Fri Nov 29 00:53:12 2002 +++ /usr/src/linux/drivers/char/pc_keyb.c Thu May 1 02:30:45 2003 @@ -13,6 +13,11 @@ * Code fixes to handle mouse ACKs properly. * C. Scott Ananian 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 @@ -85,6 +90,10 @@ /* * PS/2 Auxiliary Device */ +#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING +static int disable_trackpad_while_typing=0; +static int trackpad_delay=HZ; /* delay trackpad for 1Sec after a key-event */ +#endif static int __init psaux_init(void); @@ -449,6 +458,10 @@ return; } +#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING + if(disable_trackpad_while_typing > 0) return; +#endif + prev_code = scancode; add_mouse_randomness(scancode); if (aux_count) { @@ -467,8 +480,42 @@ static unsigned char kbd_exists = 1; +#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING + +void enable_trackpad(unsigned long ptr) +{ + disable_trackpad_while_typing=0; /* re-enable trackpad */ +} + +#endif + static inline void handle_keyboard_event(unsigned char scancode) { + +#ifdef CONFIG_DISABLE_TRACKPAD_WHILE_TYPING + + /* setup a timer to re-enable the trackpad */ + static struct timer_list enable_trackpad_timer; + static int enable_trackpad_timer_initialized=0; + + disable_trackpad_while_typing=1; /* disable trackpad */ + + if(enable_trackpad_timer_initialized) + { + /* trackpad timer already exists, - just restart it */ + mod_timer(&enable_trackpad_timer, jiffies+trackpad_delay); + } + else + { + /* no trackpad timer yet. Initialize and start it */ + init_timer(&enable_trackpad_timer); + enable_trackpad_timer.expires=jiffies+trackpad_delay; + enable_trackpad_timer.function=enable_trackpad; + add_timer(&enable_trackpad_timer); + enable_trackpad_timer_initialized=1; + } +#endif + #ifdef CONFIG_VT kbd_exists = 1; if (do_acknowledge(scancode)) --------------040904010309040302080300-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/