From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) (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 AB4A21EBA0D; Thu, 3 Apr 2025 14:05:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743689111; cv=none; b=R42kXsKuXsakCtKLVKNsiWDYYj8kjWK2zQgK2S0w4rZp3We0HDNzy5bDn31mY5XWzureYKKh6GMV5sYAmRK6mZVGmtqRi17sXPqqs7JeZqHkiv5kjjiVo64jXNY5u0UBpAMoBqYzPW2t10kli8m5l0uKG6PzTMQ0JdjwtwHKhQo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743689111; c=relaxed/simple; bh=PnaxT91oE2fOBx9IkAmHWSinNbeK6RtKCOJUu/SU3Z8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ovhZb6t2k64CYro1IyNTtYhg1g0rZieaZ+7hEXIXns76eT/cLvJstOc+9oyvu9hQGlAGK2XFXRBWOF/sCt75SdGgK5vU2jF1k9xMoGr69tLUQGElQ6JghegUgJPYm2tPJsL1BrZLAoSHtM/3WxBg/xRJG592HfAogGC1mGRVaZ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com; spf=fail smtp.mailfrom=gmail.com; arc=none smtp.client-ip=192.198.163.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=gmail.com X-CSE-ConnectionGUID: FPj+c0C6T1C8IEYwrHZiXg== X-CSE-MsgGUID: qwKhs2lAQOGdrZtW57e9UA== X-IronPort-AV: E=McAfee;i="6700,10204,11393"; a="32702851" X-IronPort-AV: E=Sophos;i="6.15,184,1739865600"; d="scan'208";a="32702851" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Apr 2025 07:05:09 -0700 X-CSE-ConnectionGUID: zPFqkzh6Q0a6JbBaQ6A6Pw== X-CSE-MsgGUID: G1272zTrSy6xOozBmNqblw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.15,184,1739865600"; d="scan'208";a="126976066" Received: from smile.fi.intel.com ([10.237.72.58]) by orviesa006.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Apr 2025 07:05:07 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.98.2) (envelope-from ) id 1u0LBn-00000008peY-1pL3; Thu, 03 Apr 2025 17:05:03 +0300 Date: Thu, 3 Apr 2025 17:05:03 +0300 From: Andy Shevchenko To: Hans de Goede Cc: Ilpo =?iso-8859-1?Q?J=E4rvinen?= , Dan Scally , Alan Stern , Sakari Ailus , Hao Yao , Bingbu Cao , Duane , platform-driver-x86@vger.kernel.org, linux-media@vger.kernel.org Subject: Re: [PATCH v2 6/9] platform/x86: int3472: Avoid GPIO regulator spikes Message-ID: References: <20250402202510.432888-1-hdegoede@redhat.com> <20250402202510.432888-7-hdegoede@redhat.com> <474fe098-3cf0-4207-92a1-e033799a04af@redhat.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <474fe098-3cf0-4207-92a1-e033799a04af@redhat.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo On Thu, Apr 03, 2025 at 11:43:34AM +0200, Hans de Goede wrote: > On 2-Apr-25 11:04 PM, Andy Shevchenko wrote: > > On Wed, Apr 2, 2025 at 11:25 PM Hans de Goede wrote: > >> > >> Avoid the GPIO controlling the avdd regulator being driven low or high > >> for a very short time leading to spikes by adding an enable delay of 2 ms > >> and a minimum off to on delay of also 2 ms. > > > > How 2ms was derived? From experiments or is there any other hint > > (Intel published sources somewhere, etc)? > > 2 ms is the minimum time ovXXXX sensors need to have there > reset line driven logical high to properly register the reset. > > So that seemed like a sane value to use here to me. Please, add it in the commit message / comment in next version. -- With Best Regards, Andy Shevchenko