[PATCH] dell-wmi: Add a WMI event code for display on/off

[Alex Hung]

Some new Dell AIO systems have a button that generates a WMI event to
turn the LCD on/off.

BugLink: http://bugs.launchpad.net/bugs/1702541

Signed-off-by: Alex Hung <alex.hung at canonical.com>
Acked-by: Pali Rohár <pali.rohar at gmail.com>
Signed-off-by: Darren Hart <dvhart at linux.intel.com>
(backported from commit ab9bb11ccbaa9e84be2534b677fe5350c2cc2014)
Signed-off-by: Alex Hung <alex.hung at canonical.com>
---
 drivers/platform/x86/dell-wmi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c
index f2d77fe..88dd7b5 100644
--- a/drivers/platform/x86/dell-wmi.c
+++ b/drivers/platform/x86/dell-wmi.c
@@ -90,6 +90,9 @@ static const struct key_entry dell_wmi_legacy_keymap[] __initconst = {
 	{ KE_IGNORE, 0xe025, { KEY_RESERVED } },
 	{ KE_IGNORE, 0xe026, { KEY_RESERVED } },
 
+	/* LCD Display On/Off Control key */
+	{ KE_KEY,    0xe027, { KEY_DISPLAYTOGGLE } },
+
 	{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
 	{ KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
 	{ KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
-- 
2.7.4