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authorTobias Diedrich <ranma+openocd@tdiedrich.de>2017-02-12 13:35:37 +0100
committerMartin Roth <martinroth@google.com>2017-02-24 03:32:11 +0100
commit9b798d7904f50b8ad83fe43442a5a3da85789bdd (patch)
tree2963084218d35e26e76e15324f95c57d1f629ad8 /src/ec/lenovo
parent80c314d64a42d87b563f41c3f837b00d6cd8e79b (diff)
downloadcoreboot-9b798d7904f50b8ad83fe43442a5a3da85789bdd.tar.xz
ec/lenovo/h8: Guard against EC bugs in the battery status logic.
On my Thinkpad with an H8-compatible ENE KB9012 EC (GDHT92WW 1.52), when the battery is nearly full and we switch from battery to AC by plugging in the cable, the current rate will not drop to 0 immediately, but the discharging state is cleared immediately. This leads to the code trying to process an invalid rate value >0x8000, leading to a displayed rate of >1000W. This patch changes the logic to deal with these corner cases. Change-Id: Ideb588d00757f259792e5ae97729e371b63a096c Signed-off-by: Tobias Diedrich <ranma+coreboot@tdiedrich.de> Reviewed-on: https://review.coreboot.org/18349 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Martin Roth <martinroth@google.com>
Diffstat (limited to 'src/ec/lenovo')
-rw-r--r--src/ec/lenovo/h8/acpi/battery.asl29
1 files changed, 22 insertions, 7 deletions
diff --git a/src/ec/lenovo/h8/acpi/battery.asl b/src/ec/lenovo/h8/acpi/battery.asl
index 0ebc9eea9d..fef994a1d6 100644
--- a/src/ec/lenovo/h8/acpi/battery.asl
+++ b/src/ec/lenovo/h8/acpi/battery.asl
@@ -97,21 +97,36 @@ Method(BSTA, 4, NotSerialized)
Store(BAMA, Local1)
Store(Arg0, PAGE) /* Battery dynamic information */
+ /*
+ * Present rate is a 16bit signed int, positive while charging
+ * and negative while discharging.
+ */
Store(BAPR, Local2)
- if (Arg2) // charging
+ If (Arg2) // Charging
{
Or(2, Local0, Local0)
-
- If (LGreaterEqual (Local2, 0x8000)) {
+ }
+ Else
+ {
+ If (Arg3) // Discharging
+ {
+ Or(1, Local0, Local0)
+ // Negate present rate
+ Subtract(0x10000, Local2, Local2)
+ }
+ Else // Full battery, force to 0
+ {
Store(0, Local2)
}
}
- if (Arg3) // discharging
- {
- Or(1, Local0, Local0)
- Subtract(0x10000, Local2, Local2)
+ /*
+ * The present rate value must be positive now, if it is not we have an
+ * EC bug or inconsistency and force the value to 0.
+ */
+ If (LGreaterEqual (Local2, 0x8000)) {
+ Store(0, Local2)
}
Store(Local0, Index(Arg1, 0x00))