PM: Optional beeping during resume from suspend to RAM

Add a feature allowing the user to make the system beep during a resume from
suspend to RAM, on x86_64 and i386.

This is useful for the users with broken resume from RAM, so that they can
verify if the control reaches the kernel after a wake-up event.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/arch/i386/kernel/acpi/wakeup.S b/arch/i386/kernel/acpi/wakeup.S
index a2295a34b2c7..b4e2ec3c3928 100644
--- a/arch/i386/kernel/acpi/wakeup.S
+++ b/arch/i386/kernel/acpi/wakeup.S
@@ -13,6 +13,21 @@
 # cs = 0x1234, eip = 0x05
 # 
 
+#define BEEP \
+        inb     $97, %al;       \
+        outb    %al, $0x80;     \
+        movb    $3, %al;        \
+        outb    %al, $97;       \
+        outb    %al, $0x80;     \
+        movb    $-74, %al;      \
+        outb    %al, $67;       \
+        outb    %al, $0x80;     \
+        movb    $-119, %al;     \
+        outb    %al, $66;       \
+        outb    %al, $0x80;     \
+        movb    $15, %al;       \
+        outb    %al, $66;
+
 ALIGN
         .align  4096
 ENTRY(wakeup_start)
@@ -31,6 +46,11 @@ wakeup_code:
         movw    %cs, %ax
         movw    %ax, %ds                                        # Make ds:0 point to wakeup_start
         movw    %ax, %ss
+
+        testl   $1, beep_flags - wakeup_code
+        jz      1f
+        BEEP
+1:
         mov     $(wakeup_stack - wakeup_code), %sp              # Private stack is needed for ASUS board
         movw    $0x0e00 + 'S', %fs:(0x12)
 
@@ -88,6 +108,10 @@ wakeup_code:
         cmpl    $0x12345678, %eax
         jne     bogus_real_magic
 
+        testl   $2, beep_flags - wakeup_code
+        jz      1f
+        BEEP
+1:
         ljmpl   $__KERNEL_CS,$wakeup_pmode_return
 
 real_save_gdt:  .word 0
@@ -98,6 +122,7 @@ real_save_cr4:	.long 0
 real_magic:     .long 0
 video_mode:     .long 0
 video_flags:    .long 0
+beep_flags:     .long 0
 real_efer_save_restore: .long 0
 real_save_efer_edx:     .long 0
 real_save_efer_eax:     .long 0
@@ -262,6 +287,8 @@ ENTRY(acpi_copy_wakeup_routine)
         movl    %edx, video_mode - wakeup_start (%eax)
         movl    acpi_video_flags, %edx
         movl    %edx, video_flags - wakeup_start (%eax)
+        movl    s2ram_beep, %edx
+        movl    %edx, beep_flags - wakeup_start (%eax)
         movl    $0x12345678, real_magic - wakeup_start (%eax)
         movl    $0x12345678, saved_magic
         popl    %ebx