From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 B81572EBB89 for ; Wed, 3 Sep 2025 21:29:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756935000; cv=none; b=oAaS8ETcYotX+ciKb9701dV6yShcVhd0wEPidu375RatG/87mRImRIMN1ml4igvZA/ZCtiQDPv7QGu0+A+Tg492AV3xc03Au6o6Li4BTVWTGcTP0Oe48MfFAosqHLjz55+W04ETpTOsmAHcVMqrinA/WPhImUBYWABsuaf7EmIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756935000; c=relaxed/simple; bh=oCiyzq52/ZtRwo9JpfJBzpVpzYKaZjipLdGuP8jqfm4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GPIEH3ju+Zy1tadEPR5ANcSM7LV4DPW5NebPycWz3+H/as5pKpd4ANngYUwSiwbUkrDxsfWgVpZ9fqA4Y133xoPehLjssvjfZHG2Z+BEPf/CJb7CeXAt+jQRap71dXrdzon0GR1rZNXwgSqIaytor/Lx5QE7Dv3bykK5FaTwdVg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=Vztf87wj; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="Vztf87wj" Received: from pendragon.ideasonboard.com (230.215-178-91.adsl-dyn.isp.belgacom.be [91.178.215.230]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id D43BC6F3; Wed, 3 Sep 2025 23:28:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1756934926; bh=oCiyzq52/ZtRwo9JpfJBzpVpzYKaZjipLdGuP8jqfm4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Vztf87wjW8RhsSEsYPzu46DomRk4zijEXbXDF9qUdVpAg7FXI9Q4vrRlaL7fQksp4 oxd5y4gjO48ohqqJwkEE3r22+ZAgvWlSdtE2nIyfPBAes4VoDvZL1PI5pRTPo59jtM Z8PLxoIHvojZMo4LIQSxfk+neTArDPkuNNjNo3hw= Date: Wed, 3 Sep 2025 23:29:35 +0200 From: Laurent Pinchart To: Sakari Ailus Cc: linux-media@vger.kernel.org, hans@jjverkuil.nl, Prabhakar , Kate Hsuan , Alexander Shiyan , Dave Stevenson , Tommaso Merciai , Umang Jain , Benjamin Mugnier , Sylvain Petinot , Christophe JAILLET , Julien Massot , Naushir Patuck , "Yan, Dongcheng" , "Cao, Bingbu" , "Qiu, Tian Shu" , "Wang, Hongju" , Stefan Klug , Mirela Rabulea , =?utf-8?B?QW5kcsOp?= Apitzsch , Heimir Thor Sverrisson , Kieran Bingham , Stanislaw Gruszka , Mehdi Djait , Ricardo Ribalda Delgado , Hans de Goede , Jacopo Mondi , Tomi Valkeinen Subject: Re: [PATCH v11 40/66] media: Document enable_streams and disable_streams behaviour Message-ID: <20250903212935.GA3648@pendragon.ideasonboard.com> References: <20250825095107.1332313-1-sakari.ailus@linux.intel.com> <20250825095107.1332313-41-sakari.ailus@linux.intel.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 In-Reply-To: <20250825095107.1332313-41-sakari.ailus@linux.intel.com> Hi Sakari, Thank you for the patch. On Mon, Aug 25, 2025 at 12:50:41PM +0300, Sakari Ailus wrote: > Document that enable_streams may start additional streams and > disable_streams may not disable requested streams if other related streams > are still enabled. > > Signed-off-by: Sakari Ailus > --- > include/media/v4l2-subdev.h | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h > index 4b28086808c9..96a9c869ffb1 100644 > --- a/include/media/v4l2-subdev.h > +++ b/include/media/v4l2-subdev.h > @@ -814,6 +814,10 @@ struct v4l2_subdev_state { > * V4L2_SUBDEV_CAP_STREAMS sub-device capability flag can ignore the mask > * argument. > * > + * Starting the requested streams may require starting additional > + * streams. Streams that are started together due to hardware are called a > + * stream group. I initially interpreted this as meaning that, to start the requested streams at the hardware level, the caller may need to start additional streams. That is, the .enable_streams() call may not have any effect until other streams are also started by the caller. > + * > * @disable_streams: Disable the streams defined in streams_mask on the given > * source pad. Subdevs that implement this operation must use the active > * state management provided by the subdev core (enabled through a call to > @@ -823,6 +827,9 @@ struct v4l2_subdev_state { > * Drivers that support only a single stream without setting the > * V4L2_SUBDEV_CAP_STREAMS sub-device capability flag can ignore the mask > * argument. > + * > + * A stream is only disabled once all streams in the stream group are > + * disabled. But this implies it's the other way around. A clarification is needed. Which behaviour are you trying to document ? > */ > struct v4l2_subdev_pad_ops { > int (*enum_mbus_code)(struct v4l2_subdev *sd, -- Regards, Laurent Pinchart