[U-Boot] [PATCH v2 2/5] input: Provide a board specific mechanism to decide whether to skip i8042 init

Simon Glass sjg at chromium.org
Sat Oct 13 02:02:02 CEST 2012


From: Gabe Black <gabeblack at chromium.org>

This change adds a board overridable function which can be used to decide
whether or not to initialize the i8042 keyboard controller. On systems where
it isn't actually connected to anything, this can save a significant amount of
boot time.

On Stumpy, this saves about 200ms on boot.

Signed-off-by: Gabe Black <gabeblack at chromium.org>
Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v2:
- Use __weak instead of the long attribute form

 drivers/input/i8042.c |   13 ++++++++++++-
 1 files changed, 12 insertions(+), 1 deletions(-)

diff --git a/drivers/input/i8042.c b/drivers/input/i8042.c
index 6839c6b..3a4c467 100644
--- a/drivers/input/i8042.c
+++ b/drivers/input/i8042.c
@@ -26,6 +26,7 @@
 /* includes */
 
 #include <common.h>
+#include <linux/compiler.h>
 
 #ifdef CONFIG_USE_CPCIDVI
 extern u8 gt_cpcidvi_in8(u32 offset);
@@ -320,6 +321,16 @@ static int kbd_controller_present(void)
 	return in8(I8042_STATUS_REG) != 0xff;
 }
 
+/*
+ * Implement a weak default function for boards that optionally
+ * need to skip the i8042 initialization.
+ */
+int __weak board_i8042_skip(void)
+{
+	/* As default, don't skip */
+	return 0;
+}
+
 /*******************************************************************************
  *
  * i8042_kbd_init - reset keyboard and init state flags
@@ -329,7 +340,7 @@ int i8042_kbd_init(void)
 	int keymap, try;
 	char *penv;
 
-	if (!kbd_controller_present())
+	if (!kbd_controller_present() || board_i8042_skip())
 		return -1;
 
 #ifdef CONFIG_USE_CPCIDVI
-- 
1.7.7.3



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