New patch to review for coreboot: 11456c2 libpayload: Remove unnecessary keyboard mode setting code

[Shawn Nematbakhsh]

Shawn Nematbakhsh ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3883

-gerrit

commit 11456c27af4f55c1f6fc3f6f5e495eab4d722766
Author: Shawn Nematbakhsh 
Date:   Fri Aug 23 14:12:24 2013 -0700

libpayload: Remove unnecessary keyboard mode setting code

keyboard_init attempts to read the existing mode register, set the
    'XLATE' bit, and write it back. The implementation is buggy because the
    keyboard may be active at the time we read the mode, and we can
    misinterpret scancode data as the reply to our command. It leads to
    problems where the KB gets disabled in firmware.

In fact, setting the 'XLATE' bit is completely unnecessary, even if we
    desire QEMU keyboard support. We already set this bit when we initialize
    the keyboard in pc_keyboard_init. Basically, this code does nothing
    (or worse), so just remove it.

Change-Id: Iab23f03fa8bced74842c33a7d263de5f449bb983
    Signed-off-by: Shawn Nematbakhsh 
---
 payloads/libpayload/drivers/keyboard.c | 55 ----------------------------------
 1 file changed, 55 deletions(-)

diff --git a/payloads/libpayload/drivers/keyboard.c b/payloads/libpayload/drivers/keyboard.c
index cfb4d0b..3639507 100644
--- a/payloads/libpayload/drivers/keyboard.c
+++ b/payloads/libpayload/drivers/keyboard.c
@@ -31,11 +31,6 @@
 #include <libpayload-config.h>
 #include <libpayload.h>

-#define I8042_CMD_READ_MODE  0x20
-#define I8042_CMD_WRITE_MODE 0x60
-
-#define I8042_MODE_XLATE     0x40
-
 struct layout_maps {
    const char *country;
    const unsigned short map[4][0x57];
@@ -261,40 +256,6 @@ int keyboard_getchar(void)
    return ret;
 }

-static int keyboard_wait_read(void)
-{
-	int retries = 10000;
-
-	while(retries-- && !(inb(0x64) & 0x01))
-		udelay(50);
-
-	return (retries <= 0) ? -1 : 0;
-}
-
-static int keyboard_wait_write(void)
-{
-	int retries = 10000;
-
-	while(retries-- && (inb(0x64) & 0x02))
-		udelay(50);
-
-	return (retries <= 0) ? -1 : 0;
-}
-
-static unsigned char keyboard_get_mode(void)
-{
-	outb(I8042_CMD_READ_MODE, 0x64);
-	keyboard_wait_read();
-	return inb(0x60);
-}
-
-static void keyboard_set_mode(unsigned char mode)
-{
-	outb(I8042_CMD_WRITE_MODE, 0x64);
-	keyboard_wait_write();
-	outb(mode, 0x60);
-}
-
 /**
  * Set keyboard layout
  * @param country string describing the keyboard layout language.
@@ -326,29 +287,13 @@ static struct console_input_driver cons = {

void keyboard_init(void)
 {
-	u8 mode;
    map = &keyboard_layouts[0];

/* If 0x64 returns 0xff, then we have no keyboard
     * controller */
-
    if (inb(0x64) == 0xFF)
    	return;

-	/* Empty keyboard buffer */
-	while (keyboard_havechar()) keyboard_getchar();
-
-	/* Read the current mode */
-	mode = keyboard_get_mode();
-
-	/* Turn on scancode translate mode so that we can
-	   use the scancode set 1 tables */
-
-	mode |= I8042_MODE_XLATE;
-
-	/* Write the new mode */
-	keyboard_set_mode(mode);
-
    console_add_input_driver(&cons);
 }