From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (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 9486B17BD6; Mon, 25 Aug 2025 05:42:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756100545; cv=none; b=JYfXWa0NU4GHndm2b3NUy9rO+00FofeZGsD8LFxVs5rI2PrkhwCIGVYiuaE/blbdoqwkq3uP3eRZL42InZ+iS0x9D7+eXch87RkLcXrb41QZA4o+OGMElNqQzghIpnciavm/aUz0yeFTc/CV3KmHy9xwEmJ5ohSksbc80MVn3iI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756100545; c=relaxed/simple; bh=SgDSAaeJE19D2xt9hQTX5rzEHMR4pavP+mq1cxRKkLk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aOlk/pkfVgSykty3xWWX5qrdG1WU2YYoADIe8j9AQsBC0E94vgyXFjdWFu0oH/1bbKLiNAL4pfgeIbl1rrWEhhl4r76/m8YoMEOxxG2GPrKhHPEEec/Xrc/QgsC87MGrwJ1emfrf5OtjNtj0krlLOy0zEi5RiJALow/P9D9VAUc= 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=IJzrX0k0; arc=none smtp.client-ip=192.198.163.15 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="IJzrX0k0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1756100544; x=1787636544; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=SgDSAaeJE19D2xt9hQTX5rzEHMR4pavP+mq1cxRKkLk=; b=IJzrX0k0RSWvjMuOktTbG8zrE/GDUdu19ZRIBqVpWgQRe+yqKCFFYT89 aeYdIAZJEiAXL0ZTWf6I82BURg+1m74OfH0atkbrLpsOU6Iuf0gt4/EZW t+J0hqrkstK30raUg/2Snii8mqG1nBT7wRF+v+Ol0S4r4v0q9PP7nek0e zdlMrcDde1LTjCbJvlwiFGU1VzKishxTJl4gcoHr9TPLGzuCjKsQMR67N jDv5IXwrh2HuGSYjQsaylTW/bCICue+Nxj7C3cC3RXDcNW+UdNfaxwfYE oPPrbRdAqgym/e+xkmixaBktTgl8bEPYQ1THBC0x8DXYkJpcseytjkqo0 A==; X-CSE-ConnectionGUID: MAZlovxKQAaOfXUglYWScw== X-CSE-MsgGUID: ZrXj/kePTUug32fiWXzB5A== X-IronPort-AV: E=McAfee;i="6800,10657,11532"; a="58404144" X-IronPort-AV: E=Sophos;i="6.17,312,1747724400"; d="scan'208";a="58404144" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2025 22:42:23 -0700 X-CSE-ConnectionGUID: ZZE9PtKJRhCAYzli/SpFFA== X-CSE-MsgGUID: OVussu/bRgKsBweq0vqLew== X-ExtLoop1: 1 Received: from vpanait-mobl.ger.corp.intel.com (HELO kekkonen.fi.intel.com) ([10.245.245.7]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2025 22:42:20 -0700 Received: from kekkonen.localdomain (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with ESMTP id EBAA412023C; Mon, 25 Aug 2025 08:42:17 +0300 (EEST) Date: Mon, 25 Aug 2025 08:42:17 +0300 Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo From: Sakari Ailus To: Richard Leitner Cc: Dave Stevenson , Mauro Carvalho Chehab , Lee Jones , Pavel Machek , Laurent Pinchart , Hans Verkuil , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org Subject: Re: [PATCH v6 03/11] Documentation: uAPI: media: add V4L2_CID_FLASH_DURATION Message-ID: References: <20250716-ov9282-flash-strobe-v6-0-934f12aeff33@linux.dev> <20250716-ov9282-flash-strobe-v6-3-934f12aeff33@linux.dev> Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250716-ov9282-flash-strobe-v6-3-934f12aeff33@linux.dev> Hi Richard, Thanks for the update (and for the ping!). On Wed, Jul 16, 2025 at 11:06:53AM +0200, Richard Leitner wrote: > Add the new strobe_duration control to v4l uAPI documentation. > > Signed-off-by: Richard Leitner > --- > Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst > index d22c5efb806a183a3ad67ec3e6550b002a51659a..03a58ef94be7c870f55d5a9bb09503995dbfb402 100644 > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-flash.rst > @@ -186,3 +186,8 @@ Flash Control IDs > charged before strobing. LED flashes often require a cooldown period > after strobe during which another strobe will not be possible. This > is a read-only control. > + > +``V4L2_CID_FLASH_DURATION (integer)`` > + Duration the flash should be on when the flash LED is in flash mode > + (V4L2_FLASH_LED_MODE_FLASH). The unit should be microseconds (µs) > + if possible. > I think we should add this is related to the hardware strobe. How about: ``V4L2_CID_FLASH_DURATION (integer)`` Duration of the flash strobe from the strobe source, typically a camera sensor. Controlling the flash LED strobe length this way requires that the flash LED driver's :ref:`flash LED mode ` is set to ``V4L2_FLASH_LED_MODE_FLASH`` and :ref:`strobe source ` is set to ``V4L2_FLASH_STROBE_SOURCE_EXTERNAL``. The unit should be microseconds (µs) if possible. This requires of course the appropriate labels. I also wonder whether we should use 0,1 µs or even ns for the unit. -- Kind regards, Sakari Ailus