From patchwork Sat Feb 25 11:51:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Armin Wolf X-Patchwork-Id: 656551 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DDF47C7EE2F for ; Sat, 25 Feb 2023 11:52:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229700AbjBYLwI (ORCPT ); Sat, 25 Feb 2023 06:52:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229558AbjBYLwA (ORCPT ); Sat, 25 Feb 2023 06:52:00 -0500 Received: from mout.gmx.net (mout.gmx.net [212.227.17.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B96419F31; Sat, 25 Feb 2023 03:51:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.de; s=s31663417; t=1677325914; i=w_armin@gmx.de; bh=Kf5tr2Sg9Jqyp+j3xyIw9/QWCzBL3T6tk+vssRythnI=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date:In-Reply-To:References; b=c0xUIIR4n8Ta7Pq7e9hvf2X5cHaEbZm+PoZFbaPg7b6b2EFiv+u1G33ibkY4OZrql 6boChBK+jv1p4hPBagpvxw/b2Luc7pu2DKvhhz4Au2CpIRA9WfUO93GfRpE5QdCXkQ 8qztMahw+2Ti0FIwILlblrTUIFQDpHNGU57Lfq44Ofzxiw7Ri7coBD/9Bt2uY3NFYq UpvtfMIyVSE/VV9wtjfaFv+byC6cnd3ru8KNSVeIxOBdN4i6VyohLUrZMb15Gy+Phf E6Lmz4KgbZx1kWiMSSHhUdjEkzgrmJguL7UYxizCZTz0gsJiqFAllmphnSrCCziM0K SkrRXClOn0Omg== X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a Received: from esprimo-mx.users.agdsn.de ([141.30.226.129]) by mail.gmx.net (mrgmx104 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MoO24-1oh6wL3TUO-00oncz; Sat, 25 Feb 2023 12:51:53 +0100 From: Armin Wolf To: rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 4/4] ACPI: SBS: Fix handling of Smart Battery Selectors Date: Sat, 25 Feb 2023 12:51:44 +0100 Message-Id: <20230225115144.31212-5-W_Armin@gmx.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230225115144.31212-1-W_Armin@gmx.de> References: <20230225115144.31212-1-W_Armin@gmx.de> MIME-Version: 1.0 X-Provags-ID: V03:K1:kj0EMGZQOKo1DIaNjvZpdw3cvFja6SPU6xwfeorMcBeWFCVw6om FI+9RGDNPJYSLetid2vlfeRQ8ezH1yS1/XRSl+IzjZ2pwwqynn4BWZE3n5ojhbQ+uYVU/VU jMzfJo1uWW89NvOij2tvDDT3I1tKFhg5a/9fAMTyrEd6VoqeI7uOr3I8rHe8ofm+Dp2urY2 4j+iEnIFP5bNho5eWkcTw== UI-OutboundReport: notjunk:1;M01:P0:snJFoJxO8+A=;9EANH49BVgQJ+cJ9Rrl5EWnzryP AG3yl9+7tQjbsZJvilgZzt90Lc9RIjMtdUhVcY9xZPm9mgkRZPac55jy6gaP/9hsL40NbEfxR VoHYMJSQkuXbbz0lZerepE++ZRoqSA/dleeizyygNsMBoLWlFI3nQ71ME6aZxaSQPD7XfBwnP 4e+DbzGmdu5xaenKPkpjr+RFHCVZPmqaxrKbcniCBahpItLzPr7hneZmcd2vXiHrMnEKuBnr7 ZGserGNwEwW+w5jAbjvXpp4ZxzS1PjyCcK/aV70KB1vC6rghuf5Ra6wdSsYelH3snGQrLJiZb Oi9poOAPNF7JuSzs9Bs2g5nlZsmIwG/JT9t5P4ZGRdIVa3spxPWZ8fo2BMWYCGAcdp0H8Mbom 1sWpS6V0Ki0NLbo7gQz96w24+sAwQQMfnG14C7xvI1IUQ3A8eXTPcR+pRpq+MQrQgdKVBcfbB YgVFC1y+D17aHLTyOGisLeDkdcfz+XUFCZVcz4Bd07cs4eZ2wBnTk0ORbEdZIHDHdG6e28hP6 j5e5Rb3RnBlecMEJqzQ+yiro8ewhD1yuOlcw07/i09K+l2m1IiD71SKT7P2wZcbtqL4KEFowM 4HNL6BC3VLx10awDe83BPpTBuWWtg9/z5qAmuFzeJZF/shlhggW247d83lDKnxzHtmjx/LvZ6 fDSyW8Zlk4Ht9tZQ5MgIr93w9y44AcZmrOCZOq3BbfDiZkXy0UDjmEVtHFxjdAB/v4fchnTt6 7VdnZuVPxH4XVnYkAEHWvECVlLqLweVg2PFYVgHOswJTcvmKxTggNGUc9QmtxxJCBjxVNTp9z bsOfRMWHbUb5xB2Xo8muPkrUT5OldYPhbyibr/S6DMqnsjrFjaWsh2wdSAcEQBrCelsEHzViD 4roC4p8QYUijIyhcZvBflYhVO0A56iQAXBryWDZtRbuKV+NBRGLpI11WisE8bi+JY650rthPM pPHD92ESyUDgjLMtRkL1zb0Q4ZA= Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org The "Smart Battery Selector" standard says that when writing SelectorState (0x1), the nibbles which should not be modified need to be masked with 0xff. This is necessary since in contrast to a "Smart Battery Manager", the last three nibbles are writable. Failing to do so might trigger the following cycle: 1. Host accidentally changes power source of the system (3rd nibble) when selecting a battery. 2. Power source is invalid, Selector changes to another power source. 3. Selector notifies host that it changed the power source. 4. Host re-reads some batteries. 5. goto 1 for each re-read battery. This loop might also be entered when a battery which is not present is selected for SMBus access. In the end some workqueues fill up, which causes the system to lockup upon suspend/shutdown. Fix this by correctly masking the value to be written, and avoid selecting batteries which are absent. Tested on a Acer Travelmate 4002WLMi. Signed-off-by: Armin Wolf --- drivers/acpi/sbs.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) -- 2.30.2 diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c index e90752d4f488..94e3c000df2e 100644 --- a/drivers/acpi/sbs.c +++ b/drivers/acpi/sbs.c @@ -473,23 +473,32 @@ static const struct device_attribute alarm_attr = { -------------------------------------------------------------------------- */ static int acpi_battery_read(struct acpi_battery *battery) { - int result = 0, saved_present = battery->present; + int result, saved_present = battery->present; u16 state; if (battery->sbs->manager_present) { result = acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER, 0x01, (u8 *)&state); - if (!result) - battery->present = state & (1 << battery->id); - state &= 0x0fff; + if (result) + return result; + + battery->present = state & (1 << battery->id); + if (!battery->present) + return 0; + + /* Masking necessary for Smart Battery Selectors */ + state = 0x0fff; state |= 1 << (battery->id + 12); acpi_smbus_write(battery->sbs->hc, SMBUS_WRITE_WORD, ACPI_SBS_MANAGER, 0x01, (u8 *)&state, 2); - } else if (battery->id == 0) - battery->present = 1; - - if (result || !battery->present) - return result; + } else { + if (battery->id == 0) { + battery->present = 1; + } else { + if (!battery->present) + return 0; + } + } if (saved_present != battery->present) { battery->update_time = 0;