Re: [BISECTED] HP G7000 battery disappears after suspend

From: Bartlomiej Zolnierkiewicz
Date: Wed Jul 08 2009 - 17:40:19 EST


On Wednesday 08 July 2009 21:41:17 Rafael J. Wysocki wrote:
> On Wednesday 08 July 2009, Alan Jenkins wrote:
> > Hi,
> >
> > I've borrowed this laptop for a few days. Linux works pretty well,
> > but I found a problem on newer kernels. After suspend it claims the
> > battery has been removed. E.g. /proc/acpi/battery/BAT0/state claims
> > the battery is not present (but it is).
> >
> > I've attached acpidump and dmidecode output at
> > <http://bugzilla.kernel.org/show_bug.cgi?id=13745>. I still have
> > access to the laptop for further tests, but only until Friday.
> >
> > I bisected it to the commit below. Manually reverting the patch fixes
> > the problem (in both 2.6.30 and 2.6.31-rc2).
>
> Well, the commit below can't be reverted, because that would cause the boxes
> it fixed to stop working.
>
> Now, the only case this patch can make any difference is when the BIOS doesn't
> set SCI_EN before returning control the the kernel, which quite evidently is a
> BIOS bug. The fact that the battery doesn't work with this patch applied means
> that the BIOS not only doesn't set SCI_EN, but also expects it to remain unset,
> which is insane.
>
> IMO this is a "won't fix", sorry.

Lets be pragmatic here..

Besides this is a regression and we are already handling some such insane
systems in STR case. Moreover sending SMI ACPI_ENABLE command may result in
some things happening behind our back and not only setting of SCI_EN bit..

PS Looking at the set_sci_en_on_resume quirk history it seems that if we are
lucky we may may fix another issue (screaming IRQ one) at the same time :)

Alan, could you try this patch?

---
debug patch (needs to have both CONFIG_SUSPEND=y & CONFIG_HIBERNATION=y)

drivers/acpi/sleep.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

Index: b/drivers/acpi/sleep.c
===================================================================
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -383,6 +383,14 @@ static struct dmi_system_id __initdata a
},
},
{
+ .callback = init_set_sci_en_on_resume,
+ .ident = "Hewlett-Packard HP G7000 Notebook PC",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "HP G7000 Notebook PC"),
+ },
+ },
+ {
.callback = init_old_suspend_ordering,
.ident = "Panasonic CF51-2L",
.matches = {
@@ -472,7 +480,10 @@ static void acpi_hibernation_leave(void)
* If ACPI is not enabled by the BIOS and the boot kernel, we need to
* enable it here.
*/
- acpi_enable();
+ if (set_sci_en_on_resume)
+ acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
+ else
+ acpi_enable();
/* Reprogram control registers and execute _BFS */
acpi_leave_sleep_state_prep(ACPI_STATE_S4);
/* Check the hardware signature */
--
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