From 68da166491655bc54051bf04c78ce648e2e33508 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Fri, 10 Oct 2014 12:19:03 -0700 Subject: Input: i8042 - disable active multiplexing by default Active multiplexing is a nice feature as it allows several pointing devices (such as touchpad and external mouse) use their native protocols at the same time. Unfortunately many manufacturers do not implement the feature properly even though they advertise it. The problematic implementations are never fixed, since Windows by default does not use this mode, and move from one BIOS/model of laptop to another. When active multiplexing is broken turning it on usually results in touchpad, keyboard, or both unresponsive. With PS/2 usage on decline (most of PS/2 devices in use nowadays are internal laptop touchpads), I expect number of users who have laptops with working MUX implementation, docking stations with external PS/2 ports, and who are still using external PS/2 mice, to be rather small. Let's flip the default to be OFF and allow activating it through i8042.nomux=0 kernel option. We'll also keep DMI table where we can record known good models. Acked-by: Jiri Kosina Acked-by: Hans de Goede Signed-off-by: Dmitry Torokhov --- Documentation/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 10d51c2f10d7..6b1054387023 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1237,7 +1237,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. i8042.noloop [HW] Disable the AUX Loopback command while probing for the AUX port i8042.nomux [HW] Don't check presence of an active multiplexing - controller + controller. Default: true. i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX controllers i8042.notimeout [HW] Ignore timeout condition signalled by controller -- cgit v1.2.2