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

[Colin Ian King]

On Tue, 2011-05-24 at 10:19 +0200, Stefan Bader wrote:
> On 23.05.2011 16:06, 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();
> >   }
> > 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();
> Agree with John. Probably there are some definitions for the previous three bits 
> and adding the bit there would help to detect when upstream starts to use it. 

I'm being dull here, and not understanding what you are saying.  Do you
mind explaining this a little more?

> But otherwise nice and good to have. :)
> 
> Acked (though there is not really one needed for O yet)
> 
> -Stefan
>