From patchwork Mon Jun 13 21:03:41 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rhyland Klein X-Patchwork-Id: 9174373 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A8CE16048C for ; Mon, 13 Jun 2016 21:05:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9943422064 for ; Mon, 13 Jun 2016 21:05:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8E234262AE; Mon, 13 Jun 2016 21:05:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1732822064 for ; Mon, 13 Jun 2016 21:05:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161222AbcFMVFx (ORCPT ); Mon, 13 Jun 2016 17:05:53 -0400 Received: from hqemgate15.nvidia.com ([216.228.121.64]:19801 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161183AbcFMVFw (ORCPT ); Mon, 13 Jun 2016 17:05:52 -0400 Received: from hqnvupgp08.nvidia.com (Not Verified[216.228.121.13]) by hqemgate15.nvidia.com id ; Mon, 13 Jun 2016 14:05:37 -0700 Received: from HQMAIL105.nvidia.com ([172.20.187.12]) by hqnvupgp08.nvidia.com (PGP Universal service); Mon, 13 Jun 2016 14:03:15 -0700 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Mon, 13 Jun 2016 14:03:15 -0700 Received: from HQMAIL105.nvidia.com (172.20.187.12) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1130.7; Mon, 13 Jun 2016 21:05:51 +0000 Received: from hqnvemgw01.nvidia.com (172.20.150.20) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server id 15.0.1130.7 via Frontend Transport; Mon, 13 Jun 2016 21:05:51 +0000 Received: from rklein-work.nvidia.com (Not Verified[10.2.68.87]) by hqnvemgw01.nvidia.com with Trustwave SEG (v7, 5, 5, 8150) id ; Mon, 13 Jun 2016 14:05:51 -0700 From: Rhyland Klein To: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse CC: , , Krzysztof Kozlowski , Rhyland Klein Subject: [PATCH] power_supply: fix return value of get_property Date: Mon, 13 Jun 2016 17:03:41 -0400 Message-ID: <1465851821-1163-1-git-send-email-rklein@nvidia.com> X-Mailer: git-send-email 1.9.1 X-NVConfidentiality: public MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP power_supply_get_property() should ideally return -EAGAIN if it is called while the power_supply is being registered. There was no way previously to determine if use_cnt == 0 meant that the power_supply wasn't fully registered yet, or if it had already been unregistered. Add a new boolean to the power_supply struct to simply show if registration is completed. Signed-off-by: Rhyland Klein --- This patch continues what was discussed with the patch "power_supply: power_supply_read_temp only if use_cnt > 0". Looking at the thermal code, it looks like we should indeed return EAGAIN if possible, and since this change is fairly simple, I think it makes sense to do it. drivers/power/power_supply_core.c | 6 +++++- include/linux/power_supply.h | 1 + 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c index b13cd074c52a..a39a47672979 100644 --- a/drivers/power/power_supply_core.c +++ b/drivers/power/power_supply_core.c @@ -491,8 +491,11 @@ int power_supply_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { - if (atomic_read(&psy->use_cnt) <= 0) + if (atomic_read(&psy->use_cnt) <= 0) { + if (!psy->initialized) + return -EAGAIN; return -ENODEV; + } return psy->desc->get_property(psy, psp, val); } @@ -775,6 +778,7 @@ __power_supply_register(struct device *parent, if (rc) goto create_triggers_failed; + psy->initialized = true; /* * Update use_cnt after any uevents (most notably from device_add()). * We are here still during driver's probe but diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h index 751061790626..3965503315ef 100644 --- a/include/linux/power_supply.h +++ b/include/linux/power_supply.h @@ -248,6 +248,7 @@ struct power_supply { struct delayed_work deferred_register_work; spinlock_t changed_lock; bool changed; + bool initialized; atomic_t use_cnt; #ifdef CONFIG_THERMAL struct thermal_zone_device *tzd;