[PATCH] platform/x86: asus-wmi: restore battery charge limit support

[Luis Miguel Arias]

On ASUS systems where the charge threshold is supported through
ASUS_WMI_DEVID_RSOC, initializing charge_end_threshold to -1 causes
the sysfs attribute to return -ENODATA. This makes TLP consider
charge threshold support unavailable.

Initialize the cached threshold to 100 instead, allowing userspace
to set the desired threshold normally.

Tested on ASUS with TLP 1.8.0:

Before this change:
* charge_end_threshold = -1
* TLP reported no charge threshold support

After this change:
* TLP reports "charge threshold" as supported
* natacpi (asus_wmi) is active
* charge_control_end_threshold can be set to 80%

Signed-off-by: Luis Miguel Arias <luismiguel@xxxxxxxxxxxx>
---
 drivers/platform/x86/asus-wmi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 80144c412..87363b198 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -1586,7 +1586,7 @@ static int asus_wmi_battery_add(struct power_supply *battery, struct acpi_batter
 	 * platforms retains it, therefore signal the threshold as unknown
 	 * until user explicitly sets it to a new value.
 	 */
-	charge_end_threshold = -1;
+	charge_end_threshold = 100;
 
 	return 0;
 }
-- 
2.47.3