From: Josef Gajdusek Date: Tue, 17 Jun 2014 21:15:49 +0000 (+0200) Subject: ACPI / battery: fix wrong value of capacity_now reported when fully charged X-Git-Tag: v3.16-rc5~24^2~3^4 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=232de514379082e7ec431c66c9713a6ef23d5dcb;p=linux.git 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 --- 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 *