From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E156DC43219 for ; Tue, 30 Apr 2019 14:23:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC7C620835 for ; Tue, 30 Apr 2019 14:23:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727141AbfD3OXx (ORCPT ); Tue, 30 Apr 2019 10:23:53 -0400 Received: from mga12.intel.com ([192.55.52.136]:15074 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726303AbfD3OXw (ORCPT ); Tue, 30 Apr 2019 10:23:52 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 30 Apr 2019 07:23:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,414,1549958400"; d="scan'208";a="144871779" Received: from mylly.fi.intel.com (HELO mylly.fi.intel.com.) ([10.237.72.154]) by fmsmga008.fm.intel.com with ESMTP; 30 Apr 2019 07:23:49 -0700 From: Jarkko Nikula To: linux-i2c@vger.kernel.org Cc: Wolfram Sang , Keijo Vaara , linux-input@vger.kernel.org, Bjorn Helgaas , "Rafael J . Wysocki" , Jarkko Nikula , stable@vger.kernel.org Subject: [PATCH] i2c: Prevent runtime suspend of adapter when Host Notify is required Date: Tue, 30 Apr 2019 17:23:22 +0300 Message-Id: <20190430142322.15013-1-jarkko.nikula@linux.intel.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Multiple users have reported their Synaptics touchpad has stopped working between v4.20.1 and v4.20.2 when using SMBus interface. The culprit for this appeared to be commit c5eb1190074c ("PCI / PM: Allow runtime PM without callback functions") that fixed the runtime PM for i2c-i801 SMBus adapter. Those Synaptics touchpad are using i2c-i801 for SMBus communication and testing showed they are able to get back working by preventing the runtime suspend of adapter. Normally when i2c-i801 SMBus adapter transmits with the client it resumes before operation and autosuspends after. However, if client requires SMBus Host Notify protocol, what those Synaptics touchpads do, then the host adapter must not go to runtime suspend since then it cannot process incoming SMBus Host Notify commands the client may send. Fix this by keeping I2C/SMBus adapter active in case client requires Host Notify. Reported-by: Keijo Vaara Link: https://bugzilla.kernel.org/show_bug.cgi?id=203297 Fixes: c5eb1190074c ("PCI / PM: Allow runtime PM without callback functions") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Jarkko Nikula --- Keijo: could you test this does it fix the issue you reported? This is practically the same diff I sent earlier what you probably haven't tested yet. I wanted to send a commitable fix in case it works since I'll be out of office in a few coming days. --- drivers/i2c/i2c-core-base.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 38af18645133..8149c9e32b69 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -327,6 +327,8 @@ static int i2c_device_probe(struct device *dev) if (client->flags & I2C_CLIENT_HOST_NOTIFY) { dev_dbg(dev, "Using Host Notify IRQ\n"); + /* Keep adapter active when Host Notify is required */ + pm_runtime_get_sync(&client->adapter->dev); irq = i2c_smbus_host_notify_to_irq(client); } else if (dev->of_node) { irq = of_irq_get_byname(dev->of_node, "irq"); @@ -431,6 +433,8 @@ static int i2c_device_remove(struct device *dev) device_init_wakeup(&client->dev, false); client->irq = client->init_irq; + if (client->flags & I2C_CLIENT_HOST_NOTIFY) + pm_runtime_put(&client->adapter->dev); return status; } -- 2.20.1