From patchwork Tue Sep 1 21:03:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 11749507 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B7EC7109B for ; Tue, 1 Sep 2020 21:04:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D8F4207D3 for ; Tue, 1 Sep 2020 21:04:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729188AbgIAVEP (ORCPT ); Tue, 1 Sep 2020 17:04:15 -0400 Received: from mga01.intel.com ([192.55.52.88]:43615 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727927AbgIAVDd (ORCPT ); Tue, 1 Sep 2020 17:03:33 -0400 IronPort-SDR: 4VybYq7qwrbGHLHrQxy9tIVWCpGrKnzHvHe2dYUWK/LLF6hIEpQU6YkOEB414bR+I7IhT2PMyx ZFwTxqX83xlQ== X-IronPort-AV: E=McAfee;i="6000,8403,9731"; a="175317803" X-IronPort-AV: E=Sophos;i="5.76,380,1592895600"; d="scan'208";a="175317803" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Sep 2020 14:03:32 -0700 IronPort-SDR: ELaLDu3ELT71dl+CWOO/vukOarvEKPuJIVxFjlx1xbJCXoRPjrtUc1Mp8hfJsDarRHodJGWFLo La7mrwkGnEeg== X-IronPort-AV: E=Sophos;i="5.76,380,1592895600"; d="scan'208";a="501886792" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Sep 2020 14:03:27 -0700 Received: from punajuuri.localdomain (punajuuri.localdomain [192.168.240.130]) by paasikivi.fi.intel.com (Postfix) with ESMTP id 85C97226B7; Wed, 2 Sep 2020 00:03:24 +0300 (EEST) Received: from sailus by punajuuri.localdomain with local (Exim 4.92) (envelope-from ) id 1kDDRF-0002DR-DA; Wed, 02 Sep 2020 00:03:33 +0300 From: Sakari Ailus To: linux-i2c@vger.kernel.org Cc: Wolfram Sang , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Greg Kroah-Hartman , rajmohan.mani@intel.com, Tomasz Figa , Bartosz Golaszewski , Bingbu Cao , Chiranjeevi Rapolu , Hyungwoo Yang , linux-media@vger.kernel.org Subject: [PATCH v7 3/6] ov5670: Support probe whilst the device is in a low power state Date: Wed, 2 Sep 2020 00:03:30 +0300 Message-Id: <20200901210333.8462-4-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200901210333.8462-1-sakari.ailus@linux.intel.com> References: <20200901210333.8462-1-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@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);