[U-Boot] [PATCH v2 5/7] 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>
Acked-by: Simon Glass <sjg at chromium.org>

---

Changes in v2:
- Reorder this patch to follow the i8042 driver clean up patches

 drivers/input/i8042.c | 43 +++++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/drivers/input/i8042.c b/drivers/input/i8042.c
index a6d0d59..3812733 100644
--- a/drivers/input/i8042.c
+++ b/drivers/input/i8042.c
@@ -454,51 +454,50 @@ static void kbd_conv_char(unsigned char scan_code)
 
 static int kbd_reset(void)
 {
-	/* KB Reset */
+	u8 config;
+
+	/* controller self test */
 	if (kbd_input_empty() == 0)
 		return -1;
+	out8(I8042_CMD_REG, CMD_SELF_TEST);
+	if (kbd_output_full() == 0)
+		return -1;
+	if (in8(I8042_DATA_REG) != KBC_TEST_OK)
+		return -1;
 
+	/* keyboard reset */
+	if (kbd_input_empty() == 0)
+		return -1;
 	out8(I8042_DATA_REG, CMD_RESET_KBD);
-
 	if (kbd_output_full() == 0)
 		return -1;
-
 	if (in8(I8042_DATA_REG) != KBD_ACK)
 		return -1;
-
 	if (kbd_output_full() == 0)
 		return -1;
-
 	if (in8(I8042_DATA_REG) != KBD_POR)
 		return -1;
 
+	/* set AT translation and disable irq */
 	if (kbd_input_empty() == 0)
 		return -1;
-
-	/* Set KBC mode */
-	out8(I8042_CMD_REG, CMD_WR_CONFIG);
-
-	if (kbd_input_empty() == 0)
+	out8(I8042_CMD_REG, CMD_RD_CONFIG);
+	if (kbd_output_full() == 0)
 		return -1;
-
-	out8(I8042_DATA_REG,
-	     CONFIG_AT_TRANS | CONFIG_SET_BIST | CONFIG_KIRQ_EN);
-
+	config = in8(I8042_DATA_REG);
+	config |= CONFIG_AT_TRANS;
+	config &= ~(CONFIG_KIRQ_EN | CONFIG_MIRQ_EN);
 	if (kbd_input_empty() == 0)
 		return -1;
-
-	/* Enable Keyboard */
-	out8(I8042_CMD_REG, CMD_KBD_EN);
+	out8(I8042_CMD_REG, CMD_WR_CONFIG);
 	if (kbd_input_empty() == 0)
 		return -1;
+	out8(I8042_DATA_REG, config);
 
-	out8(I8042_CMD_REG, CMD_WR_CONFIG);
+	/* enable keyboard */
 	if (kbd_input_empty() == 0)
 		return -1;
-
-	out8(I8042_DATA_REG,
-	     CONFIG_AT_TRANS | CONFIG_MCLK_DIS |
-	     CONFIG_KCLK_DIS | CONFIG_SET_BIST);
+	out8(I8042_CMD_REG, CMD_KBD_EN);
 	if (kbd_input_empty() == 0)
 		return -1;
 
-- 
1.8.2.1