Re: [ACPI] [TRIVIAL] Re: [PATCH] ACPI update (20030122)

[Ducrot Bruno]

On Fri, Jan 24, 2003 at 03:22:22AM +0100, Sergio Visinoni wrote:
> * Grover, Andrew ([e-mail]) wrote:
> > (2.4) S4BIOS support (Ducrot Bruno)
> 
> Attached is the missing s4bios portion (the
> acpi_enter_sleep_state_s4bios function ) + fixes to make it
> build correctly on a 2.4.20 tree.
> 
> It should apply correctly on 2.4.21-pre3 as well (not tested).
> 

It should be OK (I think..)

Appart the following chunk:

--- linux-2.4.20/drivers/acpi/hardware/hwsleep.c.s4bios~	2003-01-24 02:35:41.000000000 +0100
+++ linux-2.4.20/drivers/acpi/hardware/hwsleep.c	2003-01-24 02:35:53.000000000 +0100
@@ -339,6 +387,8 @@
 
 	ACPI_FUNCTION_TRACE ("acpi_leave_sleep_state");
 
+	/* Be sure to have BM arbitration */
+	status = acpi_set_register (ACPI_BITREG_ARB_DISABLE, 0, ACPI_MTX_LOCK);
 
 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
 
@@ -371,8 +421,5 @@
 		return_ACPI_STATUS (status);
 	}
 
-	/* Disable BM arbitration */
-	status = acpi_set_register (ACPI_BITREG_ARB_DISABLE, 0, ACPI_MTX_LOCK);
-
 	return_ACPI_STATUS (status);
 }

which is a bug fix for a different purpose.

We can not trust the bios when we have to enter the _WAK method.
Those we re-enable the BM arbitration before (the comment Disable
is actually a mistake).

Cheers,

-- 
Ducrot Bruno

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.