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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 8BA2AC433DF for ; Wed, 26 Aug 2020 11:53:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5C0D120707 for ; Wed, 26 Aug 2020 11:53:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729189AbgHZLvM (ORCPT ); Wed, 26 Aug 2020 07:51:12 -0400 Received: from mga06.intel.com ([134.134.136.31]:17928 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729181AbgHZLvF (ORCPT ); Wed, 26 Aug 2020 07:51:05 -0400 IronPort-SDR: CedqNMWSajI1h6eUL0+jOS2jdozmk69QzHpskD+iRrMudJn1CBKAUtZHO5d4VmCeOE+k5MRk+u ApRHU1N4XohQ== X-IronPort-AV: E=McAfee;i="6000,8403,9724"; a="217822885" X-IronPort-AV: E=Sophos;i="5.76,355,1592895600"; d="scan'208";a="217822885" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Aug 2020 04:50:58 -0700 IronPort-SDR: 45btBJ3Fh4xEeSU/JjsxGTjrvYWzd+ac0ValhMUhBCn3aJFlHtVtBZ+gaGx7Je4pMJuR1e+VhX 04DpG52DM7tQ== X-IronPort-AV: E=Sophos;i="5.76,355,1592895600"; d="scan'208";a="331754184" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Aug 2020 04:50:53 -0700 Received: from punajuuri.localdomain (punajuuri.localdomain [192.168.240.130]) by paasikivi.fi.intel.com (Postfix) with ESMTP id 6B3E9209B8; Wed, 26 Aug 2020 14:50:51 +0300 (EEST) Received: from sailus by punajuuri.localdomain with local (Exim 4.92) (envelope-from ) id 1kAu0e-0001bP-Q6; Wed, 26 Aug 2020 14:54:32 +0300 From: Sakari Ailus To: linux-i2c@vger.kernel.org Cc: Wolfram Sang , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, Bingbu Cao , linux-media@vger.kernel.org, Chiranjeevi Rapolu , Hyungwoo Yang , Bartosz Golaszewski , Arnd Bergmann , linux-kernel@vger.kernel.org, Greg Kroah-Hartman , rajmohan.mani@intel.com, Tomasz Figa , "Qiu, Tian Shu" Subject: [PATCH v6 3/6] ov5670: Support probe whilst the device is in a low power state Date: Wed, 26 Aug 2020 14:54:29 +0300 Message-Id: <20200826115432.6103-4-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200826115432.6103-1-sakari.ailus@linux.intel.com> References: <20200826115432.6103-1-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org Tell ACPI device PM code that the driver supports the device being in a low power state when the driver's probe function is entered. Also do identification on the first access of the device, whether in probe or when starting streaming. Signed-off-by: Sakari Ailus --- drivers/media/i2c/ov5670.c | 76 +++++++++++++++++++++++--------------- 1 file changed, 46 insertions(+), 30 deletions(-) diff --git a/drivers/media/i2c/ov5670.c b/drivers/media/i2c/ov5670.c index f26252e35e08d..74b0325c22565 100644 --- a/drivers/media/i2c/ov5670.c +++ b/drivers/media/i2c/ov5670.c @@ -1832,6 +1832,8 @@ struct ov5670 { /* Streaming on/off */ bool streaming; + /* True if the device has been identified */ + bool identified; }; #define to_ov5670(_sd) container_of(_sd, struct ov5670, sd) @@ -2270,6 +2272,32 @@ static int ov5670_get_skip_frames(struct v4l2_subdev *sd, u32 *frames) return 0; } +/* Verify chip ID */ +static int ov5670_identify_module(struct ov5670 *ov5670) +{ + struct i2c_client *client = v4l2_get_subdevdata(&ov5670->sd); + int ret; + u32 val; + + if (ov5670->identified) + return 0; + + ret = ov5670_read_reg(ov5670, OV5670_REG_CHIP_ID, + OV5670_REG_VALUE_24BIT, &val); + if (ret) + return ret; + + if (val != OV5670_CHIP_ID) { + dev_err(&client->dev, "chip id mismatch: %x!=%x\n", + OV5670_CHIP_ID, val); + return -ENXIO; + } + + ov5670->identified = true; + + return 0; +} + /* Prepare streaming by writing default values and customized values */ static int ov5670_start_streaming(struct ov5670 *ov5670) { @@ -2278,6 +2306,10 @@ static int ov5670_start_streaming(struct ov5670 *ov5670) int link_freq_index; int ret; + ret = ov5670_identify_module(ov5670); + if (ret) + return ret; + /* Get out of from software reset */ ret = ov5670_write_reg(ov5670, OV5670_REG_SOFTWARE_RST, OV5670_REG_VALUE_08BIT, OV5670_SOFTWARE_RST); @@ -2401,27 +2433,6 @@ static int __maybe_unused ov5670_resume(struct device *dev) return 0; } -/* Verify chip ID */ -static int ov5670_identify_module(struct ov5670 *ov5670) -{ - struct i2c_client *client = v4l2_get_subdevdata(&ov5670->sd); - int ret; - u32 val; - - ret = ov5670_read_reg(ov5670, OV5670_REG_CHIP_ID, - OV5670_REG_VALUE_24BIT, &val); - if (ret) - return ret; - - if (val != OV5670_CHIP_ID) { - dev_err(&client->dev, "chip id mismatch: %x!=%x\n", - OV5670_CHIP_ID, val); - return -ENXIO; - } - - return 0; -} - static const struct v4l2_subdev_video_ops ov5670_video_ops = { .s_stream = ov5670_set_stream, }; @@ -2456,6 +2467,7 @@ static int ov5670_probe(struct i2c_client *client) struct ov5670 *ov5670; const char *err_msg; u32 input_clk = 0; + bool low_power; int ret; device_property_read_u32(&client->dev, "clock-frequency", &input_clk); @@ -2472,11 +2484,14 @@ static int ov5670_probe(struct i2c_client *client) /* Initialize subdev */ v4l2_i2c_subdev_init(&ov5670->sd, client, &ov5670_subdev_ops); - /* Check module identity */ - ret = ov5670_identify_module(ov5670); - if (ret) { - err_msg = "ov5670_identify_module() error"; - goto error_print; + low_power = acpi_dev_state_low_power(&client->dev); + if (!low_power) { + /* Check module identity */ + ret = ov5670_identify_module(ov5670); + if (ret) { + err_msg = "ov5670_identify_module() error"; + goto error_print; + } } mutex_init(&ov5670->mutex); @@ -2513,10 +2528,10 @@ static int ov5670_probe(struct i2c_client *client) ov5670->streaming = false; /* - * Device is already turned on by i2c-core with ACPI domain PM. - * Enable runtime PM and turn off the device. + * Don't set the device's state to active if it's in a low power state. */ - pm_runtime_set_active(&client->dev); + if (!low_power) + pm_runtime_set_active(&client->dev); pm_runtime_enable(&client->dev); pm_runtime_idle(&client->dev); @@ -2558,7 +2573,7 @@ static const struct dev_pm_ops ov5670_pm_ops = { #ifdef CONFIG_ACPI static const struct acpi_device_id ov5670_acpi_ids[] = { - {"INT3479"}, + { "INT3479" }, { /* sentinel */ } }; @@ -2573,6 +2588,7 @@ static struct i2c_driver ov5670_i2c_driver = { }, .probe_new = ov5670_probe, .remove = ov5670_remove, + .flags = I2C_DRV_FL_ALLOW_LOW_POWER_PROBE, }; module_i2c_driver(ov5670_i2c_driver); -- 2.20.1