From 232de514379082e7ec431c66c9713a6ef23d5dcb Mon Sep 17 00:00:00 2001 From: Josef Gajdusek Date: Tue, 17 Jun 2014 23:15:49 +0200 Subject: [PATCH] ACPI / battery: fix wrong value of capacity_now reported when fully charged It seems that some batteries (noticed on DELL JYPJ136) assume capacity_now = design_capacity when fully charged. This causes reported capacity to suddenly jump to >full_charge_capacity (and that means capacity reported to userspace is >100% and incorrect) values after 99%. This patch detects capacity_now > full_charge_capacity, notifies userspace (unless it is the known bug where capacity_now == design_capacity) and trims the value to full_charge_capacity. Signed-off-by: Josef Gajdusek Signed-off-by: Rafael J. Wysocki --- drivers/acpi/battery.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index bc0b286ff2ba..130f513e08c9 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -535,6 +535,20 @@ static int acpi_battery_get_state(struct acpi_battery *battery) " invalid.\n"); } + /* + * When fully charged, some batteries wrongly report + * capacity_now = design_capacity instead of = full_charge_capacity + */ + if (battery->capacity_now > battery->full_charge_capacity + && battery->full_charge_capacity != ACPI_BATTERY_VALUE_UNKNOWN) { + battery->capacity_now = battery->full_charge_capacity; + if (battery->capacity_now != battery->design_capacity) + printk_once(KERN_WARNING FW_BUG + "battery: reported current charge level (%d) " + "is higher than reported maximum charge level (%d).\n", + battery->capacity_now, battery->full_charge_capacity); + } + if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags) && battery->capacity_now >= 0 && battery->capacity_now <= 100) battery->capacity_now = (battery->capacity_now * -- 2.20.1