ACPI events on T20 thinkpad stop being reported

ACPI events on T20 thinkpad stop being reported

[Florian Zumbiehl]

Hi,

I have here a T20 thinkpad with a T22 BIOS and a 2.6.32 kernel. After
boot, acpi_listen shows me all the events that are being generated by
the lid switch, hotkeys, batteries, ac, and maybe more. However,
when I disconnect and reconnect ac power a few times in rapid
succession, that leads to all of these events not being reported
anymore. Suspend to RAM and to disk both don't fix it, only a
reboot does.

After I posted this on the thinkpad-acpi mailing list, I was told
that this probably was a problem with the EC (driver|firmware),
so that's why I am addressing this to you now :-)

The BIOS and EC firmware are the newest versions available
(1.12 and 1.06, respectively).

Any hints as to how to debug or possibly even fix this would be
appreciated.

Florian

Re: ACPI events on T20 thinkpad stop being reported

[Alexey Starikovskiy]

[-- Attachment #1: Type: text/plain, Size: 983 bytes --]

Hi,
Please check if the attached patch helps
If it does not, please open bug report at bugzilla.kernel.org against ACPI/EC.

Regards,
Alex.
Florian Zumbiehl пишет:
> Hi,
> 
> I have here a T20 thinkpad with a T22 BIOS and a 2.6.32 kernel. After
> boot, acpi_listen shows me all the events that are being generated by
> the lid switch, hotkeys, batteries, ac, and maybe more. However,
> when I disconnect and reconnect ac power a few times in rapid
> succession, that leads to all of these events not being reported
> anymore. Suspend to RAM and to disk both don't fix it, only a
> reboot does.
> 
> After I posted this on the thinkpad-acpi mailing list, I was told
> that this probably was a problem with the EC (driver|firmware),
> so that's why I am addressing this to you now :-)
> 
> The BIOS and EC firmware are the newest versions available
> (1.12 and 1.06, respectively).
> 
> Any hints as to how to debug or possibly even fix this would be
> appreciated.
> 
> Florian


[-- Attachment #2: acpi_ec_return_udelay_at_transaction_start.patch --]
[-- Type: text/x-diff, Size: 820 bytes --]

ACPI: EC: Put back small delay at the transaction start

From: Alexey Starikovskiy <astarikovskiy@suse.de>

Commit 2a84cb removed delay needed by some slow controllers (Acer TM4001)
Put it back.
References: http://bugzilla.kernel.org/show_bug.cgi?id=14747
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
---

 drivers/acpi/ec.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)


diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 75b147f..dce126f 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -217,6 +217,8 @@ static int ec_poll(struct acpi_ec *ec)
 {
 	unsigned long flags;
 	int repeat = 2; /* number of command restarts */
+	/* allow EC to digest command */
+	udelay(ACPI_EC_CDELAY);
 	while (repeat--) {
 		unsigned long delay = jiffies +
 			msecs_to_jiffies(ACPI_EC_DELAY);