[PATCH] ACPI: battery: Force "Discharging" status on battery for ASUS TUF Gaming A16

[PATCH] ACPI: battery: Force "Discharging" status on battery for ASUS TUF Gaming A16

[calvitohq]

From: Marco <soytucalvitofavorito@icloud.com>

On the ASUS TUF Gaming A16 (FA608UMI), after AC is unplugged the ACPI
_BST status word reports neither the charging nor the discharging bit
set, so the battery driver reports "Not charging" (and UPower
"fully-charged") even though the battery is actively discharging
(current_now stays positive).

This is the same class of firmware bug as the ASUS Vivobook 18
M1807HA (Launchpad bug 2152185), where the status flips between
"Full"/"Not charging"/"Discharging". Add a DMI quirk that, when the
system is running on battery, forces a computed "Full" or
"Not charging" status to "Discharging".

Based on the M1807HA quirk patch by Norman Becker.

Signed-off-by: Marco <soytucalvitofavorito@icloud.com>
---
 drivers/acpi/battery.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -58,6 +58,7 @@
 static int battery_bix_broken_package;
 static int battery_notification_delay_ms;
 static int battery_ac_is_broken;
+static bool battery_force_discharging;
 static unsigned int cache_time = 1000;
 module_param(cache_time, uint, 0644);
 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
@@ -192,6 +193,19 @@
 		battery->full_charge_capacity < battery->design_capacity;
 }
 
+static void acpi_battery_force_discharging_fix_status(union power_supply_propval *val)
+{
+	if (!battery_force_discharging)
+		return;
+
+	if (power_supply_is_system_supplied())
+		return;
+
+	if (val->intval == POWER_SUPPLY_STATUS_FULL ||
+	    val->intval == POWER_SUPPLY_STATUS_NOT_CHARGING)
+		val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+}
+
 static int acpi_battery_get_property(struct power_supply *psy,
 				     enum power_supply_property psp,
 				     union power_supply_propval *val)
@@ -250,6 +264,7 @@
 			val->intval = POWER_SUPPLY_STATUS_FULL;
 		else
 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		acpi_battery_force_discharging_fix_status(val);
 		break;
 	case POWER_SUPPLY_PROP_PRESENT:
 		val->intval = acpi_battery_present(battery);
@@ -1258,6 +1273,13 @@
 	return 0;
 }
 
+static int __init
+battery_force_discharging_quirk(const struct dmi_system_id *d)
+{
+	battery_force_discharging = true;
+	return 0;
+}
+
 static const struct dmi_system_id bat_dmi_table[] __initconst = {
 	{
 		/* NEC LZ750/LS */
@@ -1294,6 +1316,15 @@
 			DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
 		},
 	},
+	{
+		/* ASUS TUF Gaming A16 FA608UMI */
+		.callback = battery_force_discharging_quirk,
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "ASUS"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "TUF Gaming A16 FA608UMI"),
+			DMI_MATCH(DMI_BOARD_NAME, "FA608UMI"),
+		},
+	},
 	{},
 };
 

Re: [PATCH] ACPI: battery: Force "Discharging" status on battery for ASUS TUF Gaming A16

[Rafael J. Wysocki (Intel)]

On Sat, Sep 26, 2026 at 3:25 PM <calvitohq@gmail.com> wrote:
>
> From: Marco <soytucalvitofavorito@icloud.com>
>
> On the ASUS TUF Gaming A16 (FA608UMI), after AC is unplugged the ACPI
> _BST status word reports neither the charging nor the discharging bit
> set, so the battery driver reports "Not charging" (and UPower
> "fully-charged") even though the battery is actively discharging
> (current_now stays positive).
>
> This is the same class of firmware bug as the ASUS Vivobook 18
> M1807HA (Launchpad bug 2152185), where the status flips between
> "Full"/"Not charging"/"Discharging". Add a DMI quirk that, when the
> system is running on battery, forces a computed "Full" or
> "Not charging" status to "Discharging".
>
> Based on the M1807HA quirk patch by Norman Becker.
>
> Signed-off-by: Marco <soytucalvitofavorito@icloud.com>
> ---
>  drivers/acpi/battery.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
>
> --- a/drivers/acpi/battery.c
> +++ b/drivers/acpi/battery.c
> @@ -58,6 +58,7 @@
>  static int battery_bix_broken_package;
>  static int battery_notification_delay_ms;
>  static int battery_ac_is_broken;
> +static bool battery_force_discharging;
>  static unsigned int cache_time = 1000;
>  module_param(cache_time, uint, 0644);
>  MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
> @@ -192,6 +193,19 @@
>                 battery->full_charge_capacity < battery->design_capacity;
>  }
>
> +static void acpi_battery_force_discharging_fix_status(union power_supply_propval *val)
> +{
> +       if (!battery_force_discharging)
> +               return;
> +
> +       if (power_supply_is_system_supplied())
> +               return;
> +

The two checks above can be combined.

> +       if (val->intval == POWER_SUPPLY_STATUS_FULL ||
> +           val->intval == POWER_SUPPLY_STATUS_NOT_CHARGING)

What about POWER_SUPPLY_STATUS_CHARGING?

> +               val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
> +}
> +
>  static int acpi_battery_get_property(struct power_supply *psy,
>                                      enum power_supply_property psp,
>                                      union power_supply_propval *val)
> @@ -250,6 +264,7 @@
>                         val->intval = POWER_SUPPLY_STATUS_FULL;
>                 else
>                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +               acpi_battery_force_discharging_fix_status(val);

Also it looks like you want the status to be
POWER_SUPPLY_STATUS_DISCHARGING always if battery_force_discharging is
set and power_supply_is_system_supplied() returns 'false' which can be
checked upfront in the POWER_SUPPLY_PROP_STATUS case.

>                 break;
>         case POWER_SUPPLY_PROP_PRESENT:
>                 val->intval = acpi_battery_present(battery);
> @@ -1258,6 +1273,13 @@
>         return 0;
>  }
>
> +static int __init
> +battery_force_discharging_quirk(const struct dmi_system_id *d)
> +{
> +       battery_force_discharging = true;
> +       return 0;
> +}
> +
>  static const struct dmi_system_id bat_dmi_table[] __initconst = {
>         {
>                 /* NEC LZ750/LS */
> @@ -1294,6 +1316,15 @@
>                         DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
>                 },
>         },
> +       {
> +               /* ASUS TUF Gaming A16 FA608UMI */
> +               .callback = battery_force_discharging_quirk,
> +               .matches = {
> +                       DMI_MATCH(DMI_SYS_VENDOR, "ASUS"),
> +                       DMI_MATCH(DMI_PRODUCT_NAME, "TUF Gaming A16 FA608UMI"),
> +                       DMI_MATCH(DMI_BOARD_NAME, "FA608UMI"),
> +               },
> +       },
>         {},
>  };
>
>