Change in coreboot[master]: ec/chromeec: Fix battery ACPI mutex level

[Matt DeVillier (Code Review)]

Matt DeVillier has uploaded this change for review. ( https://review.coreboot.org/23697

Change subject: ec/chromeec: Fix battery ACPI mutex level
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ec/chromeec: Fix battery ACPI mutex level

Commit 07fe618 [chromeec: Add support for reading second battery info]
added a Mutex as part of the ACPI code to determine battery statuses.

Windows is extremely picky about ACPI code, and attempting to acquire
a level 1 mutex without first having acquired a level 0 mutex causes
Windows to hang on boot. Since there's no reason to use a level 1
mutex here, change it to level 0.

Test: Boot Windows on device with ChromeEC without hanging

Change-Id: Icfb0817cfe0c49eb4527a12b507362939a6d32c6
Signed-off-by: Matt DeVillier 
---
M src/ec/google/chromeec/acpi/battery.asl
1 file changed, 1 insertion(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/97/23697/1

diff --git a/src/ec/google/chromeec/acpi/battery.asl b/src/ec/google/chromeec/acpi/battery.asl
index d8056b0..0a0caec 100644
--- a/src/ec/google/chromeec/acpi/battery.asl
+++ b/src/ec/google/chromeec/acpi/battery.asl
@@ -17,7 +17,7 @@
 // Scope (EC0)

/* Mutex for EC battery index interface */
-Mutex (BATM, 1)
+Mutex (BATM, 0)

// Wait for desired battery index to be presented in shared memory
 //   Arg0 = battery index