[PATCH 2/3] power: supply: Don't count 'unknown' scope power supplies

From: Mario Limonciello
Date: Thu Sep 28 2023 - 12:35:36 EST


On some systems AMD Navi3x dGPU triggers RAS errors on startup; but
only if the amdgpu kernel module is not part of the initramfs.
This is because the hardware is not properly programmed for the
AC/DC state of the system when it is loaded later in boot.

The AC/DC state of the system is incorrect specifically when UCSI power
supplies have been initialized. These power supplies are marked as
POWER_SUPPLY_SCOPE_UNKNOWN scope. As they're 'offline' the power
supply count is increased but the resultant return value is
power_supply_is_system_supplied() 0.

To fix this look explicitly for `POWER_SUPPLY_SCOPE_SYSTEM` power
supplies before incrementing the count. If no system power supply
is found then the system is assumed to be on AC.

Cc: stable@xxxxxxxxxxxxxxx
Tested-by: David Perry <David.Perry@xxxxxxx>
Fixes: 95339f40a8b6 ("power: supply: Fix logic checking if system is running from battery")
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
drivers/power/supply/power_supply_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index d325e6dbc770..3de6e6d00815 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -349,7 +349,7 @@ static int __power_supply_is_system_supplied(struct device *dev, void *data)
unsigned int *count = data;

if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_SCOPE, &ret))
- if (ret.intval == POWER_SUPPLY_SCOPE_DEVICE)
+ if (ret.intval != POWER_SUPPLY_SCOPE_SYSTEM)
return 0;

(*count)++;
--
2.34.1