[PATCH] thinkpad_acpi: use BDSS to set force_discharge

0001-thinkpad_acpi-use-BDSS-to-set-force_discharge.patch

From 234dbcfa353de7d8bca9f5c9dec6ce9c196faec7 Mon Sep 17 00:00:00 2001
From: Thomas Koch <linrunner@gmx.net>
Date: Thu, 26 Jul 2018 07:01:01 +0200
Subject: [PATCH] thinkpad_acpi: use BDSS to set force_discharge

PSBS won't work on all (relevant) ThinkPads, so mimic tpacpi-bat
with BDSS.

Signed-off-by: Thomas Koch <linrunner@gmx.net>
---
 drivers/platform/x86/thinkpad_acpi.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 80e32d5..0273765 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -9249,7 +9249,7 @@ static struct ibm_struct mute_led_driver_data = {
 #define GET_INHIBIT	"BICG"
 
 #define GET_DISCHARGE	"BDSG"
-#define SET_DISCHARGE	"PSBS"
+#define SET_DISCHARGE	"BDSS"
 
 #define INHIBIT_ATTR	"inhibit_charge"
 #define DISCHARGE_ATTR	"force_discharge"
@@ -9397,8 +9397,10 @@ static int tpacpi_battery_set(int what, int battery, int value)
 		}
 		return 0;
 	case FORCE_DISCHARGE:
-		param = battery;
-		param |= value << 8;
+		/* Force discharge is in bit 0,
+		 * break on AC attach is in bit 1 (won't work on some ThinkPads),
+		 * battery ID is in bits 8-9, 2 bits.
+		 */
 		if ACPI_FAILURE(tpacpi_battery_acpi_eval(SET_DISCHARGE, &ret, param)) {
 			pr_err("failed to set force dischrage on %d", battery);
 			return -ENODEV;
-- 
2.7.4