[PATCH 1/1] UBUNTU: SAUCE: S3 early resume debug via keyboard LEDs

[John Johansen]

On 05/23/2011 07:06 AM, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
> 
> Add support to debug S3 early resume by flashing the keyboard
> LEDs three times in the realmode path.   This is useful to allow
> one to determine if S3 hangs occur in the BIOS or during the early
> resume phase.
> 
> Add kernel parameter acpi_sleep=s3_leds to enable the s3 debugging
> option.  This can also be enabled by writing 8 to
> /proc/sys/kernel/acpi_video_flags.
> 
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>  Documentation/kernel-parameters.txt      |    5 ++++-
>  arch/x86/kernel/acpi/realmode/wakemain.c |   27 +++++++++++++++++++++++++++
>  arch/x86/kernel/acpi/sleep.c             |    2 ++
>  3 files changed, 33 insertions(+), 1 deletions(-)
> 
> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
> index cc85a92..9f36ff4 100644
> --- a/Documentation/kernel-parameters.txt
> +++ b/Documentation/kernel-parameters.txt
> @@ -244,12 +244,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
>  			For broken nForce2 BIOS resulting in XT-PIC timer.
>  
>  	acpi_sleep=	[HW,ACPI] Sleep options
> -			Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
> +			Format: { s3_bios, s3_mode, s3_beep, s3_leds, s4_nohwsig,
>  				  old_ordering, s4_nonvs, sci_force_enable }
>  			See Documentation/power/video.txt for information on
>  			s3_bios and s3_mode.
>  			s3_beep is for debugging; it makes the PC's speaker beep
>  			as soon as the kernel's real-mode entry point is called.
> +			s3_leds is for debugging; it flashes the keyboard LEDs
> +			3 times as soon as the kernel's real-mode entry point is
> +			called.
>  			s4_nohwsig prevents ACPI hardware signature from being
>  			used during resume from hibernation.
>  			old_ordering causes the ACPI 1.0 ordering of the _PTS
> diff --git a/arch/x86/kernel/acpi/realmode/wakemain.c b/arch/x86/kernel/acpi/realmode/wakemain.c
> index 883962d..1d108be 100644
> --- a/arch/x86/kernel/acpi/realmode/wakemain.c
> +++ b/arch/x86/kernel/acpi/realmode/wakemain.c
> @@ -61,6 +61,30 @@ static void send_morse(const char *pattern)
>  	}
>  }
>  
> +#define I8042_STATUS_REG	0x64
> +#define I8042_DATA_REG		0x60
> +#define I8042_SET_LED_BITS	0xed
> +#define I8042_STR_IBF		0x02
> +
> +static void flash_keyboard_leds(void)
> +{
> +	int i;
> +	unsigned char leds = 7;
> +
> +	/* Flash keyboard LEDs 3 times */
> +	for (i = 0; i < 6; i++) {
> +		while (inb(I8042_STATUS_REG) & I8042_STR_IBF)
> +			;
> +		outb(I8042_SET_LED_BITS, I8042_DATA_REG);
> +		while (inb(I8042_STATUS_REG) & I8042_STR_IBF)
> +			;
> +		outb(leds, I8042_DATA_REG);
> +		leds ^= 7;
> +		udelay(500000);
> +	}
> +}
> +
> +
>  void main(void)
>  {
>  	/* Kill machine if structures are wrong */
> @@ -78,4 +102,7 @@ void main(void)
>  		probe_cards(0);
>  		set_mode(wakeup_header.video_mode);
>  	}
> +
> +	if (wakeup_header.realmode_flags & 8)
> +		flash_keyboard_leds();
I do wish this little bit used an enum or definition instead of the hard
coded 8 but since rest of the code does the same just consider it as
me whining about style

>  }
> diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
> index ff93bc1..182617c 100644
> --- a/arch/x86/kernel/acpi/sleep.c
> +++ b/arch/x86/kernel/acpi/sleep.c
> @@ -109,6 +109,8 @@ static int __init acpi_sleep_setup(char *str)
>  			acpi_realmode_flags |= 2;
>  		if (strncmp(str, "s3_beep", 7) == 0)
>  			acpi_realmode_flags |= 4;
> +		if (strncmp(str, "s3_leds", 7) == 0)
> +			acpi_realmode_flags |= 8;
>  #ifdef CONFIG_HIBERNATION
>  		if (strncmp(str, "s4_nohwsig", 10) == 0)
>  			acpi_no_s4_hw_signature();

This is really nice to have Colin, thanks

Acked-by: John Johansen <john.johansen at canonical.com>