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>

1 files changed, 12 insertions, 0 deletions

diff --git a/src/ec/lenovo/h8/h8.c b/src/ec/lenovo/h8/h8.c
index e44a2781f5..c67b3b3872 100644
--- a/src/ec/lenovo/h8/h8.c
+++ b/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;