Commit e3271a59 authored Mar 30, 2023 by Hans de Goede

platform/x86: ideapad-laptop: Stop sending KEY_TOUCHPAD_TOGGLE

Commit 5829f8a8 ("platform/x86: ideapad-laptop: Send
KEY_TOUCHPAD_TOGGLE on some models") made ideapad-laptop send
KEY_TOUCHPAD_TOGGLE when we receive an ACPI notify with VPC event bit 5 set
and the touchpad-state has not been changed by the EC itself already.

This was done under the assumption that this would be good to do to make
the touchpad-toggle hotkey work on newer models where the EC does not
toggle the touchpad on/off itself (because it is not routed through
the PS/2 controller, but uses I2C).

But it turns out that at least some models, e.g. the Yoga 7-15ITL5 the EC
triggers an ACPI notify with VPC event bit 5 set on resume, which would
now cause a spurious KEY_TOUCHPAD_TOGGLE on resume to which the desktop
environment responds by disabling the touchpad in software, breaking
the touchpad (until manually re-enabled) on resume.

It was never confirmed that sending KEY_TOUCHPAD_TOGGLE actually improves
things on new models and at least some new models like the Yoga 7-15ITL5
don't have a touchpad on/off toggle hotkey at all, while still sending
ACPI notify events with VPC event bit 5 set.

So it seems best to revert the change to send KEY_TOUCHPAD_TOGGLE when
receiving an ACPI notify events with VPC event bit 5 and the touchpad
state as reported by the EC has not changed.

Note this is not a full revert the code to cache the last EC touchpad
state is kept to avoid sending spurious KEY_TOUCHPAD_ON / _OFF events
on resume.

Fixes: 5829f8a8 ("platform/x86: ideapad-laptop: Send KEY_TOUCHPAD_TOGGLE on some models")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217234

Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230330194644.64628-1-hdegoede@redhat.com

parent e352d685

drivers/platform/x86/ideapad-laptop.c

+10 −13

Original line number	Diff line number	Diff line
		@@ -1170,7 +1170,6 @@ static const struct key_entry ideapad_keymap[] = {
		{ KE_KEY, 65, { KEY_PROG4 } },
		{ KE_KEY, 66, { KEY_TOUCHPAD_OFF } },
		{ KE_KEY, 67, { KEY_TOUCHPAD_ON } },
		{ KE_KEY, 68, { KEY_TOUCHPAD_TOGGLE } },
		{ KE_KEY, 128, { KEY_ESC } },

		/*
		@@ -1526,18 +1525,16 @@ static void ideapad_sync_touchpad_state(struct ideapad_private *priv, bool send_
		if (priv->features.ctrl_ps2_aux_port)
		i8042_command(&param, value ? I8042_CMD_AUX_ENABLE : I8042_CMD_AUX_DISABLE);

		if (send_events) {
		/*
		* On older models the EC controls the touchpad and toggles it
		* on/off itself, in this case we report KEY_TOUCHPAD_ON/_OFF.
		* If the EC did not toggle, report KEY_TOUCHPAD_TOGGLE.
		* On older models the EC controls the touchpad and toggles it on/off
		* itself, in this case we report KEY_TOUCHPAD_ON/_OFF. Some models do
		* an acpi-notify with VPC bit 5 set on resume, so this function get
		* called with send_events=true on every resume. Therefor if the EC did
		* not toggle, do nothing to avoid sending spurious KEY_TOUCHPAD_TOGGLE.
		*/
		if (value != priv->r_touchpad_val) {
		if (send_events && value != priv->r_touchpad_val) {
		ideapad_input_report(priv, value ? 67 : 66);
		sysfs_notify(&priv->platform_device->dev.kobj, NULL, "touchpad");
		} else {
		ideapad_input_report(priv, 68);
		}
		}

		priv->r_touchpad_val = value;