From patchwork Wed May 5 09:42:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 431422 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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 A82D4C43460 for ; Wed, 5 May 2021 09:42:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7AE8A61106 for ; Wed, 5 May 2021 09:42:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232936AbhEEJnl (ORCPT ); Wed, 5 May 2021 05:43:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:48708 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232504AbhEEJnR (ORCPT ); Wed, 5 May 2021 05:43:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BA8CE61581; Wed, 5 May 2021 09:42:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620207739; bh=n8BdYNFKHpGuvTsaDKiqExH9RPNm4SzImqrTD24XJEw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D5T/Giy9UwbacLo5/r243zsPBZ7bkoG9N39UtkebzGibE2JzsvfvECZm6Zbguc6Uu GTLD3m8D6+iHXCihxX/T3oEYcyShEYVZ6ZuebL91GQWXu2ErP1Pin4TxjkmC0Z3Mn4 /Rlz+WQTgF+x/qdH+qzMCxRvzMCOQpnUsbHZsPs2Oi0fV4xStJEi6cNxY96KVK42Ee lfbW+cPG8uR0sAT5xyjz37bkVSrTe7am2zPJQAnYECVG0ALKFGx2k9aPchNc6zBr/E Ursdkl9WjSgrF4HHILE35g25HfkopYqDbw/2QlF3c7I64raujdA+cbcWmF0ZLGalk4 daiAuIpELUvOw== Received: by mail.kernel.org with local (Exim 4.94) (envelope-from ) id 1leE2r-00AHx1-Lz; Wed, 05 May 2021 11:42:17 +0200 From: Mauro Carvalho Chehab Cc: linuxarm@huawei.com, mauro.chehab@huawei.com, Mauro Carvalho Chehab , Mauro Carvalho Chehab , Sakari Ailus , linux-kernel@vger.kernel.org, linux-media@vger.kernel.org Subject: [PATCH 25/25] media: i2c: ccs-core: fix pm_runtime_get_sync() usage count Date: Wed, 5 May 2021 11:42:15 +0200 Message-Id: <83ec24acb15f17e2ce589575c2f5eb7bdd1daf28.1620207353.git.mchehab+huawei@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: References: MIME-Version: 1.0 Sender: Mauro Carvalho Chehab To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The pm_runtime_get_sync() internally increments the dev->power.usage_count without decrementing it, even on errors. There is a bug at ccs_pm_get_init(): when this function returns an error, the stream is not started, and RPM usage_count should not be incremented. However, if the calls to v4l2_ctrl_handler_setup() return errors, it will be kept incremented. At ccs_suspend() the best is to replace it by the new pm_runtime_resume_and_get(), introduced by: commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") in order to properly decrement the usage counter automatically, in the case of errors. Signed-off-by: Mauro Carvalho Chehab Reviewed-by: Jonathan Cameron --- drivers/media/i2c/ccs/ccs-core.c | 39 ++++++++++++++++++++------------ 1 file changed, 24 insertions(+), 15 deletions(-) diff --git a/drivers/media/i2c/ccs/ccs-core.c b/drivers/media/i2c/ccs/ccs-core.c index b05f409014b2..04c3ab9e37b4 100644 --- a/drivers/media/i2c/ccs/ccs-core.c +++ b/drivers/media/i2c/ccs/ccs-core.c @@ -1880,21 +1880,33 @@ static int ccs_pm_get_init(struct ccs_sensor *sensor) struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd); int rval; + /* + * It can't use pm_runtime_resume_and_get() here, as the driver + * relies at the returned value to detect if the device was already + * active or not. + */ rval = pm_runtime_get_sync(&client->dev); - if (rval < 0) { - pm_runtime_put_noidle(&client->dev); + if (rval < 0) + goto error; - return rval; - } else if (!rval) { - rval = v4l2_ctrl_handler_setup(&sensor->pixel_array-> - ctrl_handler); - if (rval) - return rval; + /* Device was already active, so don't set controls */ + if (rval == 1) + return 0; - return v4l2_ctrl_handler_setup(&sensor->src->ctrl_handler); - } + /* Restore V4L2 controls to the suspended device */ + rval = v4l2_ctrl_handler_setup(&sensor->pixel_array->ctrl_handler); + if (rval) + goto error; + rval = v4l2_ctrl_handler_setup(&sensor->src->ctrl_handler); + if (rval) + goto error; + + /* Keep PM runtime usage_count incremented on success */ return 0; +error: + pm_runtime_put_noidle(&client->dev); + return rval; } static int ccs_set_stream(struct v4l2_subdev *subdev, int enable) @@ -3089,12 +3101,9 @@ static int __maybe_unused ccs_suspend(struct device *dev) bool streaming = sensor->streaming; int rval; - rval = pm_runtime_get_sync(dev); - if (rval < 0) { - pm_runtime_put_noidle(dev); - + rval = pm_runtime_resume_and_get(dev); + if (rval < 0) return rval; - } if (sensor->streaming) ccs_stop_streaming(sensor);