[3.16.y-ckt stable] Patch "hp-wmi: limit hotkey enable" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    hp-wmi: limit hotkey enable

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt19.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 8836aeffd4be092c65c04a5cd88ecc4031cba0b5 Mon Sep 17 00:00:00 2001
From: Kyle Evans <kvans32 at gmail.com>
Date: Fri, 11 Sep 2015 10:40:17 -0500
Subject: hp-wmi: limit hotkey enable

commit 8a1513b49321e503fd6c8b6793e3b1f9a8a3285b upstream.

Do not write initialize magic on systems that do not have
feature query 0xb. Fixes Bug #82451.

Redefine FEATURE_QUERY to align with 0xb and FEATURE2 with 0xd
for code clearity.

Add a new test function, hp_wmi_bios_2008_later() & simplify
hp_wmi_bios_2009_later(), which fixes a bug in cases where
an improper value is returned. Probably also fixes Bug #69131.

Add missing __init tag.

Signed-off-by: Kyle Evans <kvans32 at gmail.com>
Signed-off-by: Darren Hart <dvhart at linux.intel.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/platform/x86/hp-wmi.c | 31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/platform/x86/hp-wmi.c b/drivers/platform/x86/hp-wmi.c
index 4c559640dcba..301386c4d85b 100644
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -54,8 +54,9 @@ MODULE_ALIAS("wmi:5FB7F034-2C63-45e9-BE91-3D44E2C707E4");
 #define HPWMI_HARDWARE_QUERY 0x4
 #define HPWMI_WIRELESS_QUERY 0x5
 #define HPWMI_BIOS_QUERY 0x9
+#define HPWMI_FEATURE_QUERY 0xb
 #define HPWMI_HOTKEY_QUERY 0xc
-#define HPWMI_FEATURE_QUERY 0xd
+#define HPWMI_FEATURE2_QUERY 0xd
 #define HPWMI_WIRELESS2_QUERY 0x1b
 #define HPWMI_POSTCODEERROR_QUERY 0x2a

@@ -295,25 +296,33 @@ static int hp_wmi_tablet_state(void)
 	return (state & 0x4) ? 1 : 0;
 }

-static int __init hp_wmi_bios_2009_later(void)
+static int __init hp_wmi_bios_2008_later(void)
 {
 	int state = 0;
 	int ret = hp_wmi_perform_query(HPWMI_FEATURE_QUERY, 0, &state,
 				       sizeof(state), sizeof(state));
-	if (ret)
-		return ret;
+	if (!ret)
+		return 1;

-	return (state & 0x10) ? 1 : 0;
+	return (ret == HPWMI_RET_UNKNOWN_CMDTYPE) ? 0 : -ENXIO;
 }

-static int hp_wmi_enable_hotkeys(void)
+static int __init hp_wmi_bios_2009_later(void)
 {
-	int ret;
-	int query = 0x6e;
+	int state = 0;
+	int ret = hp_wmi_perform_query(HPWMI_FEATURE2_QUERY, 0, &state,
+				       sizeof(state), sizeof(state));
+	if (!ret)
+		return 1;

-	ret = hp_wmi_perform_query(HPWMI_BIOS_QUERY, 1, &query, sizeof(query),
-				   0);
+	return (ret == HPWMI_RET_UNKNOWN_CMDTYPE) ? 0 : -ENXIO;
+}

+static int __init hp_wmi_enable_hotkeys(void)
+{
+	int value = 0x6e;
+	int ret = hp_wmi_perform_query(HPWMI_BIOS_QUERY, 1, &value,
+				       sizeof(value), 0);
 	if (ret)
 		return -EINVAL;
 	return 0;
@@ -663,7 +672,7 @@ static int __init hp_wmi_input_setup(void)
 			    hp_wmi_tablet_state());
 	input_sync(hp_wmi_input_dev);

-	if (hp_wmi_bios_2009_later() == 4)
+	if (!hp_wmi_bios_2009_later() && hp_wmi_bios_2008_later())
 		hp_wmi_enable_hotkeys();

 	status = wmi_install_notify_handler(HPWMI_EVENT_GUID, hp_wmi_notify, NULL);