Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965735AbaFQQmQ (ORCPT ); Tue, 17 Jun 2014 12:42:16 -0400 Received: from w-smtp-out-7.wedos.net ([46.28.106.5]:47719 "EHLO we2-f167.wedos.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S965290AbaFQQmL (ORCPT ); Tue, 17 Jun 2014 12:42:11 -0400 Date: Tue, 17 Jun 2014 18:41:54 +0200 From: Josef Gajdusek To: "Rafael J. Wysocki" Cc: lenb@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] acpi/battery: fix wrong value of capacity_now reported by few battery types when fully charged (resend) Message-ID: <20140617164154.GA21113@dashie> References: <20140612145813.GB14085@dashie> <3564280.IKKn41NV0x@vostro.rjw.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3564280.IKKn41NV0x@vostro.rjw.lan> User-Agent: Mutt/1.5.22 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 attempts to detect this bug, notifies userspace and trims the value to full_charge_capacity. Signed-off-by: Josef Gajdusek --- Relaxed the check as you suggested and added printk_once. > Why don't you use the > > battery->capacity_now > battery->full_charge_capacity > > check here? That would be more robust, wouldn't it? To allow userspace to see that there is some unknown bug we do not know yet with the battery. This is taken care of much more elegantly by the printk now. diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index e48fc98..57a800c 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -532,6 +532,18 @@ 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->capacity_now = battery->full_charge_capacity; + printk_once(KERN_WARNING FW_BUG + "battery: reported current charge level (%d) " + "is higher than reported maximum charge level (%d)." + "This is normal on some systems.\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 * -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/