[U-Boot] [PATCH 2/5] x86: i8042: Correctly initialize the controller

[Bin Meng]

The existing i8042 keyboard controller driver has some issues.
First of all, it does not issue a self-test command (0xaa) to the
controller at the very beginning. Without this, the controller
does not respond any command at all. Secondly, it initializes
the configuration byte reigster to turn on keyboard's interrupt,
which is not allowed as U-Boot we don't normally enable interrupt.
Finally, at the end of the initialization routine, it wrongly
sets the controller to disable all interfaces including both
keyboard and mouse.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
---

 drivers/input/i8042.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/drivers/input/i8042.c b/drivers/input/i8042.c
index 1769c5e..3799580 100644
--- a/drivers/input/i8042.c
+++ b/drivers/input/i8042.c
@@ -664,6 +664,18 @@ static int wait_until_kbd_output_full(void)
 
 static int kbd_reset(void)
 {
+	/* controller self test */
+	if (kbd_input_empty() == 0)
+		return -1;
+
+	out8(I8042_COMMAND_REG, 0xaa);
+
+	if (wait_until_kbd_output_full() == 0)
+		return -1;
+
+	if (in8(I8042_DATA_REG) != 0x55) /* success */
+		return -1;
+
 	/* KB Reset */
 	if (kbd_input_empty() == 0)
 		return -1;
@@ -691,7 +703,7 @@ static int kbd_reset(void)
 	if (kbd_input_empty() == 0)
 		return -1;
 
-	out8(I8042_DATA_REG, 0x45);
+	out8(I8042_DATA_REG, 0x44);
 
 	if (kbd_input_empty() == 0)
 		return -1;
@@ -701,13 +713,5 @@ static int kbd_reset(void)
 	if (kbd_input_empty() == 0)
 		return -1;
 
-	out8(I8042_COMMAND_REG, 0x60);
-	if (kbd_input_empty() == 0)
-		return -1;
-
-	out8(I8042_DATA_REG, 0xf4);
-	if (kbd_input_empty() == 0)
-		return -1;
-
 	return 0;
 }
-- 
1.8.2.1