ec/lenovo/h8: Implement sticky Fn option.

Useful for accessibility.

Sticky modifier (sticky Fn) is a behaviour of modifier key when
you don't have to hold it pressed to achieve the result. E.g.
with normal Fn brightness up is:
<Press Fn> <Press Home> <Despress Home> <Depress Fn>
With sticky Fn you can do:
<Press Fn> <Depress Fn> <Press Home> <Despress Home>

Change-Id: I4da5adcea02428d936023891de08684cae77c44e
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/4661
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

src/ec/lenovo/h8/h8.c

@@ -70,6 +70,14 @@ static void h8_fn_ctrl_swap(int on)
 		ec_clr_bit(0xce, 4);
 }
 
+static void h8_sticky_fn(int on)
+{
+	if (on)
+		ec_set_bit(0x0, 3);
+	else
+		ec_clr_bit(0x0, 3);
+}
+
 static void h8_log_ec_version(void)
 {
 	char ecfw[17];
@@ -202,6 +210,10 @@ static void h8_enable(device_t dev)
 		val = 0;
 	h8_fn_ctrl_swap(val);
 
+	if (get_option(&val, "sticky_fn") != CB_SUCCESS)
+		val = 0;
+	h8_sticky_fn(val);
+
 	if (get_option(&val, "first_battery") != CB_SUCCESS)
 		val = 1;
 

src/mainboard/lenovo/t60/cmos.layout

@@ -113,6 +113,7 @@ entries
 1064         8       h       0        volume
 1072         1       e       9        first_battery
 1074         1       e       1        fn_ctrl_swap
+1075         1       e       1        sticky_fn
 # -----------------------------------------------------------------
 
 enumerations

src/mainboard/lenovo/x201/cmos.default

@@ -10,3 +10,4 @@ bluetooth=Enable
 wwan=Enable
 touchpad=Enable
 fn_ctrl_swap=Disable
+sticky_fn=Disable

src/mainboard/lenovo/x201/cmos.layout

@@ -91,6 +91,7 @@ entries
 413         1       e       1        wwan
 414         1       e       1        touchpad
 417         1       e       1        fn_ctrl_swap
+418         1       e       1        sticky_fn
 #419        565     r       0        unused
 
 # coreboot config options: check sums

src/mainboard/lenovo/x60/cmos.default

@@ -13,3 +13,4 @@ tft_brightness=0xff
 first_battery=Primary
 bluetooth=Enable
 fn_ctrl_swap=Disable
+sticky_fn=Disable

src/mainboard/lenovo/x60/cmos.layout

@@ -113,6 +113,7 @@ entries
 1081         1       e       1        bluetooth
 1082         1       e       1        wwan
 1085         1       e       1        fn_ctrl_swap
+1086         1       e       1        sticky_fn
 # -----------------------------------------------------------------
 
 enumerations