x86: Fix cosmetic issues in the i8254 and i8259 codes
This cleans up i8254 and i8259 codes to fix several cosmetic
issues, like coding convention and some comments improvement.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/pcat_timer.c b/arch/x86/lib/pcat_timer.c
index 3545a50..ce15818 100644
--- a/arch/x86/lib/pcat_timer.c
+++ b/arch/x86/lib/pcat_timer.c
@@ -9,17 +9,17 @@
#include <asm/io.h>
#include <asm/i8254.h>
-#define TIMER2_VALUE 0x0a8e /* 440Hz */
+#define TIMER2_VALUE 0x0a8e /* 440Hz */
int pcat_timer_init(void)
{
/*
- * initialize 2, used to drive the speaker
- * (to start a beep: write 3 to port 0x61,
- * to stop it again: write 0)
+ * Initialize counter 2, used to drive the speaker.
+ * To start a beep, set both bit0 and bit1 of port 0x61.
+ * To stop it, clear both bit0 and bit1 of port 0x61.
*/
outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3,
- PIT_BASE + PIT_COMMAND);
+ PIT_BASE + PIT_COMMAND);
outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2);
outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2);