[ibm-acpi-devel] [PATCH] platform/x86: thinkpad_acpi: handle HKEY 0x4012, 0x4013 events

[Alexander K. <a-...@a-...>]

Those events occur when a keyboard cover is attached to a ThinkPad
Tablet device.  Typically, they are used to switch from normal to tablet
mode in userspace; e.g., to offer touch keyboard choices when focus goes
to a text box and no keyboard is attached, or to enable autorotation of
the display according to the builtin orientation sensor.

No attempt is taken to emit an EV_SW event for SW_TABLET_MODE; this is
left to userspace.  So this patch is mainly to avoid warnings about
unknown and unhandled events, which are now reported as:

* Event 0x4012: attached keyboard cover
* Event 0x4013: detached keyboard cover

Tested as working on a ThinkPad X1 Tablet Gen 2, 20JCS00C00, and as
non-interfering with a ThinkPad X1 Carbon 7th, 20QESABM02 (normal
clamshell, so it does not have a keyboard cover).

Signed-off-by: Alexander Kobel <a-...@a-...>
---
  drivers/platform/x86/thinkpad_acpi.c | 10 +++++++++-
  1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c 
b/drivers/platform/x86/thinkpad_acpi.c
index c404706379d9..e3b5f02bafa6 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -174,6 +174,8 @@ enum tpacpi_hkey_event_t {
  						     or port replicator */
  	TP_HKEY_EV_HOTPLUG_UNDOCK	= 0x4011, /* undocked from hotplug
  						     dock or port replicator */
+	TP_HKEY_EV_KBD_COVER_ATTACH	= 0x4012, /* attached keyboard cover */
+	TP_HKEY_EV_KBD_COVER_DETACH	= 0x4013, /* detached keyboard cover */

  	/* User-interface events */
  	TP_HKEY_EV_LID_CLOSE		= 0x5001, /* laptop lid closed */
@@ -3976,7 +3978,7 @@ static bool hotkey_notify_dockevent(const u32 hkey,
  	*ignore_acpi_ev = false;

  	switch (hkey) {
-	case TP_HKEY_EV_UNDOCK_ACK:
+	case TP_HKEY_EV_UNDOCK_ACK cover:
  		/* ACPI undock operation completed after wakeup */
  		hotkey_autosleep_ack = 1;
  		pr_info("undocked\n");
@@ -3989,6 +3991,12 @@ static bool hotkey_notify_dockevent(const u32 hkey,
  	case TP_HKEY_EV_HOTPLUG_UNDOCK: /* undocked from port replicator */
  		pr_info("undocked from hotplug port replicator\n");
  		return true;
+	case TP_HKEY_EV_KBD_COVER_ATTACH: /* attached keyboard cover */
+		pr_info("attached keyboard cover\n");
+		return true;
+	case TP_HKEY_EV_KBD_COVER_DETACH: /* detached keyboard cover */
+		pr_info("detached keyboard cover\n");
+		return true;

  	default:
  		return false;
-- 
2.30.0