[XS] Change in coreboot[main]: superio/nuvoton/nct6779d: Allow swapping PS/2 keyboard/mouse ports

[Keith Hui (Code Review)]

Keith Hui has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/81884?usp=email )

Change subject: superio/nuvoton/nct6779d: Allow swapping PS/2 keyboard/mouse ports
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superio/nuvoton/nct6779d: Allow swapping PS/2 keyboard/mouse ports

Add nvram option to allow user to manually swap PS/2 keyboard and mouse
ports (i.e. keyboard port serves the mouse instead).
This is intended for mainboards with only one PS/2 port for either
keyboard or mouse. Until coreboot gets improved keyboard and mouse
detection and initialization and can decide on its own when to swap,
this option allows PS/2 mouse connected to this one port a chance
to work in the OS.

Without this support, the one PS/2 port works with keyboards only.

TEST=With nvram option added to asus/p8x7x-series/v/p8z77-m and turned
on, PS/2 mouse works.

Change-Id: I2d58719c207da973ad049cb9151d92f31ff6cd92
Signed-off-by: Keith Hui 
---
M src/superio/nuvoton/nct6779d/superio.c
1 file changed, 9 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/84/81884/1

diff --git a/src/superio/nuvoton/nct6779d/superio.c b/src/superio/nuvoton/nct6779d/superio.c
index e908c9c..09942d6 100644
--- a/src/superio/nuvoton/nct6779d/superio.c
+++ b/src/superio/nuvoton/nct6779d/superio.c
@@ -12,6 +12,7 @@
 {
    uint8_t byte;
    uint8_t power_status;
+	uint8_t swap_kbd_mouse;

if (!dev->enabled)
    	return;
@@ -38,12 +39,20 @@

power_status = get_uint_option("power_on_after_fail",
    			CONFIG_MAINBOARD_POWER_FAILURE_STATE) & 0x03;
+		swap_kbd_mouse = get_uint_option("swap_keyboard_and_mouse", 0) & 0x1;
    	pnp_enter_conf_mode(dev);
    	pnp_set_logical_device(dev);
    	byte = pnp_read_config(dev, 0xe4);
    	byte &= ~0x60;
    	byte |= (power_status << 5);
    	pnp_write_config(dev, 0xe4, byte);
+		/* Swap keyboard and mouse port if requested */
+		byte = pnp_read_config(dev, 0xe0);
+		if (swap_kbd_mouse)
+			byte |= (1 << 2);
+		else
+			byte &= ~(1 << 2);
+		pnp_write_config(dev, 0xe0, byte);
    	pnp_exit_conf_mode(dev);
    	break;
    }