From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.11]) (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 50AFAF9CB; Mon, 25 Aug 2025 05:48:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756100920; cv=none; b=DYbYME74+Wj0vhPMY9vQfe23Ncb8S6zIMZfqkRpGsaEFzLU+lrcEuefrwlUUFW5q5YGVjfql6skaSKZDIWk+zYicwTLVUC8C/Xl0v3MQAzPUJt85BeCwZKaHSeMlSrY5LR+oxCBplkRMEf5hyprUazl2wkVuaRFoNTlsbWqoFFQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756100920; c=relaxed/simple; bh=Jau+FjbOfy7Vl+xOE9VJa+DMB+eQb+pmr32ecZWVjsU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pWwnXTdwxFWwplwfCuXazXv3KgDALG8EWtVWbDPZL8+sX9+6cVmm5rmSozpUXzKIQKWtWbw6PIcy6KquQbJh1MXVOToxVNHmZZnLwdfNNcH+k8hLBG6jv31ZIKOelr7I6lkQEKjgbcNpOsOkPEi0sYu3HUacWktJPw4SZTrSEvQ= 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=aFwrdK9x; arc=none smtp.client-ip=192.198.163.11 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="aFwrdK9x" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1756100918; x=1787636918; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=Jau+FjbOfy7Vl+xOE9VJa+DMB+eQb+pmr32ecZWVjsU=; b=aFwrdK9xbGYlMHfgHK3MlJd97A/7Zye/mTOtyPbjQqMM+gTzjjuqXmys MukSrg7eT9ISLkt0mc9FJAUyirlkurz3Bq0gbD7Li0/9X5e+v9Hhn/rms sXVvfZkFKR2F26dU58J611RlOSzWwkeVxCvqsQZ7opf6QqphqGiJlkQvs uRcFBkHseyNwP/pebwNBX8cwoKGqXckunhzAsgVRQs34b59IWzgzx8Sux WGhFvVqJsOwdErXP3LwdjHx3T2GW5MCoTDJzTLTMqbu5KjAxbDwKm0gIy EbrLY+oRidwzdmBqT28oYg+gwx6Mt9HqheMn16A9K8oxmsaD2PKNKl64w w==; X-CSE-ConnectionGUID: GDpoRBcHQpqU4N0qllzAJQ== X-CSE-MsgGUID: fD/UmzMPTh6tci5A2oVIAQ== X-IronPort-AV: E=McAfee;i="6800,10657,11532"; a="68900439" X-IronPort-AV: E=Sophos;i="6.17,312,1747724400"; d="scan'208";a="68900439" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2025 22:48:37 -0700 X-CSE-ConnectionGUID: inir8pOrQie6HNXlUdaVng== X-CSE-MsgGUID: X1PuEl9VQ+qzvjbI5xM1qA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.17,312,1747724400"; d="scan'208";a="174511206" Received: from vpanait-mobl.ger.corp.intel.com (HELO kekkonen.fi.intel.com) ([10.245.245.7]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2025 22:48:34 -0700 Received: from kekkonen.localdomain (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with ESMTP id 2295D12023C; Mon, 25 Aug 2025 08:48:31 +0300 (EEST) Date: Mon, 25 Aug 2025 08:48:31 +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: On Mon, Aug 25, 2025 at 08:42:19AM +0300, Sakari Ailus wrote: > 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. Also adding a reference to V4L2_CID_FLASH_HW_STROBE_SIGNAL: ``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 strobe source's :ref:`V4L2_CID_FLASH_HW_STROBE_SIGNAL ` is enabled and 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. Similarly, the documentation for V4L2_CID_FLASH_HW_STROBE_SIGNAL should be amended with a reference, but the label needs to exist first. I think you could merge the two documentation patches to make this easier. -- Sakari Ailus