From patchwork Tue Nov 12 07:55:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanislaw Gruszka X-Patchwork-Id: 13871833 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2ACD91990AF for ; Tue, 12 Nov 2024 07:55:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.17 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731398126; cv=none; b=GSZllG6yiLPSTyCf2EoC17B7Wgcp80+OB87h6l1J+vbTSQ6KNatgvn4C3apVFKpoYHUZvtym+h5LKlh7nI2Dnr6T8HlgJS6EqrJooENnT/YBSju+MSU//t9c8xFItZ5b4bmCbAy0I862ZvqJXVTuadyrRJunUaBVk1nN7WeapmA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731398126; c=relaxed/simple; bh=8VxSQRcDnrhCOEVwLwHQkdlznsGu+FCajYsaALnrWf0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=EIh7pmTQY1lLWsHey6RmP91NreXR2AvgWlV8aHXGsT/1X+Zc3uhuxG2QrxUdL5Ysdoba5xyl8pIWnZAInJ/PcMHwlfN0dILkvQ8eE3uvFCT7aRrVDcE/ln2DFIMukpId6YsK88XV4ek61aKz6BUQFXuLISzIz84+0uN2h5bfRjE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=JnG2xbT5; arc=none smtp.client-ip=192.198.163.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="JnG2xbT5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1731398125; x=1762934125; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=8VxSQRcDnrhCOEVwLwHQkdlznsGu+FCajYsaALnrWf0=; b=JnG2xbT5QitTS9yvu7kctEG4pkLhvbwZSwm0ng6t97VQCHTar+EtMlfb eLqzZPY0nKnGiO6mrRUkySqR9bNvwZVbv4nN2xvJTr3R3QipO+pgmKxTY TEELu2hrr55R3cQEU0whnesxj+Kkbw74qbO02rNl1xLH4zPuEkroZoyd6 c9nWNHUP0hMT7K0nHCaWWqlivcAQyAVeFudbl3e6bI4DKw4RZhr13ZZWt m0ZY4/Lnpw7NEalZIobRrdD5ux/vBeJbhcIxsd1WKenhe+P6nxKHxokSb YlQxOyGLCJaqMHfZM8x15iVnwe4Db5OrE4LnIn70fgPkumwtqjlx9K0au Q==; X-CSE-ConnectionGUID: YB3WsstATQGdPK9TNfggSA== X-CSE-MsgGUID: vxGfPhCuS+qEvJMQefcUOA== X-IronPort-AV: E=McAfee;i="6700,10204,11253"; a="31092711" X-IronPort-AV: E=Sophos;i="6.12,147,1728975600"; d="scan'208";a="31092711" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Nov 2024 23:55:25 -0800 X-CSE-ConnectionGUID: 6XR+du3ISsWduS4vJtvyBw== X-CSE-MsgGUID: Us+pYUmhQOuLVhzj7mmt9g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,147,1728975600"; d="scan'208";a="87215359" Received: from sgruszka-mobl.ger.corp.intel.com (HELO localhost) ([10.246.8.237]) by orviesa010-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Nov 2024 23:55:22 -0800 From: Stanislaw Gruszka To: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, Wentong Wu , Sakari Ailus , Hans de Goede Subject: [PATCH v4 2/3] usb: misc: ljca: set small runtime autosuspend delay Date: Tue, 12 Nov 2024 08:55:13 +0100 Message-Id: <20241112075514.680712-2-stanislaw.gruszka@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241112075514.680712-1-stanislaw.gruszka@linux.intel.com> References: <20241112075514.680712-1-stanislaw.gruszka@linux.intel.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On some Lenovo platforms, the patch works around problems with ov2740 sensor initialization, which manifest themself like below: [ 4.540476] ov2740 i2c-INT3474:01: error -EIO: failed to find sensor [ 4.542066] ov2740 i2c-INT3474:01: probe with driver ov2740 failed with error -5 or [ 7.742633] ov2740 i2c-INT3474:01: chip id mismatch: 2740 != 0 [ 7.742638] ov2740 i2c-INT3474:01: error -ENXIO: failed to find sensor and also by random failures of video stream start. Issue can be reproduced by this script: n=0 k=0 while [ $n -lt 50 ] ; do sudo modprobe -r ov2740 sleep `expr $RANDOM % 5` sudo modprobe ov2740 if media-ctl -p | grep -q ov2740 ; then let k++ fi let n++ done echo Success rate $k/$n Without the patch, success rate is approximately 15 or 50 tries. With the patch it does not fail. This problem is some hardware or firmware malfunction, that can not be easy debug and fix. While setting small autosuspend delay is not perfect workaround as user can configure it to any value, it will prevent the failures by default. Additionally setting small autosuspend delay should have positive effect on power consumption as for most ljca workloads device is used for just a few milliseconds flowed by long periods of at least 100ms of inactivity (usually more). Fixes: acd6199f195d ("usb: Add support for Intel LJCA device") Cc: stable@vger.kernel.org Reviewed-by: Hans de Goede Tested-by: Hans de Goede # ThinkPad X1 Yoga Gen 8, ov2740 Acked-by: Sakari Ailus Signed-off-by: Stanislaw Gruszka --- v3 -> v4: no change in this patch v2 -> v3: add A-b tag from Sakari v1 -> v2: add R-b, T-b tags from Hans drivers/usb/misc/usb-ljca.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/usb/misc/usb-ljca.c b/drivers/usb/misc/usb-ljca.c index 8056c65e4548..d9c21f783055 100644 --- a/drivers/usb/misc/usb-ljca.c +++ b/drivers/usb/misc/usb-ljca.c @@ -811,6 +811,14 @@ static int ljca_probe(struct usb_interface *interface, if (ret) goto err_free; + /* + * This works around problems with ov2740 initialization on some + * Lenovo platforms. The autosuspend delay, has to be smaller than + * the delay after setting the reset_gpio line in ov2740_resume(). + * Otherwise the sensor randomly fails to initialize. + */ + pm_runtime_set_autosuspend_delay(&usb_dev->dev, 10); + usb_enable_autosuspend(usb_dev); return 0;