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 5D70C2D8DD0; Tue, 16 Jun 2026 11:20:18 +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=1781608821; cv=none; b=kCXgrJMuJSVxSSzCO69IqHY1Z7Y5nPdIWD/kuE9DgmAUcLdmUp/1sNDyu/0GzBCyEQvbtAl7Z7jKQBdeXFXzRS62NkAL8OySKf4B+2dMUoE4hAHHp0PgvUk/s3bioXzia47GnR7KVkoGRA/ZP3XuhEQRiv74WqeJfjDxbX/T074= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781608821; c=relaxed/simple; bh=a3OTobzVHLfzK/TYKvKxjWVhIp1VrswRkLtD5l2pFuo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=aFax9YnIqN83ll1A/iBkUv+hNU630/JXhMRIVLyvopLoJBNoGlETPzy6lQBh7wyhF9wxHjZPhevqJuyv1FbOXzEEs1tnYFn43uaiPboK70OFr7nmxA/bMzwDkt9IPxltwvFB1R+CoqSW6PsFxZ+4PvE0LMmXllGhOfGhOWgpP84= 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=b9/fAujP; 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="b9/fAujP" Received: from [192.168.88.20] (91-158-153-178.elisa-laajakaista.fi [91.158.153.178]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 47A398FA; Tue, 16 Jun 2026 13:19:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1781608776; bh=a3OTobzVHLfzK/TYKvKxjWVhIp1VrswRkLtD5l2pFuo=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=b9/fAujPxJcNFcNF6xkzXx/cE4wGPDFRJqtoc6N7Q60tfJpLfgGEAI5rXdi0XrakT pyM0C1OSefafA+Ot7tzWvHdBf5nMYFXZbUYwFc2YHV7jvFXfuTqGIhgwMD6L/iegTC Rjtsx8nh1D8SaAIhzSHTjxegKGLMiclxvWzcVzb8= Message-ID: Date: Tue, 16 Jun 2026 14:20:06 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 03/10] media: rcar-csi2: Move {enable|disable}_streams() calls To: Laurent Pinchart , =?UTF-8?Q?Niklas_S=C3=B6derlund?= Cc: Mauro Carvalho Chehab , Sakari Ailus , linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?Q?Niklas_S=C3=B6derlund?= , Mauro Carvalho Chehab , Jacopo Mondi References: <20260311-rcar-streams-v5-0-3e6c957d7567@ideasonboard.com> <20260311-rcar-streams-v5-3-3e6c957d7567@ideasonboard.com> <20260318205435.GG716464@killaraus.ideasonboard.com> From: Tomi Valkeinen Content-Language: en-US In-Reply-To: <20260318205435.GG716464@killaraus.ideasonboard.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi, On 18/03/2026 22:54, Laurent Pinchart wrote: > On Wed, Mar 11, 2026 at 03:53:16PM +0200, Tomi Valkeinen wrote: >> With multiple streams the operation to enable the CSI-2 hardware and to >> call {enable|disable}_streams() on upstream subdev will need to be >> handled separately. >> >> Prepare for that by moving {enable|disable}_streams() calls out from >> rcsi2_start() and rcsi2_stop(). >> >> On Gen3, a side effect of this change is that if the sink side devices >> call .enable_streams() on rcar-csi2 multiple times, the second call will >> fail. This is because we always use stream ID 0, so the second call >> would attempt to enable the same stream again, leading to an error. In >> other words, a normal single-stream setup continues to work, but trying >> to use the current driver's custom VC based routing will fail. > > I assume this gets addressed later in the series. Yes and no. The previous patch does the same for rcar-isp, which affects the gen4 custom VC based routing the same was this does for gen3. At the end of the series we support full multi-stream with the upstream API. The custom VC based routing is no longer supported, and will continue to fail. >> >> On Gen4, this doesn't matter as the rcar-isp behaves in a similar way as >> described above, and thus rcar-csi2 will only get a single >> .enable_streams() call. >> >> Signed-off-by: Tomi Valkeinen >> --- >> drivers/media/platform/renesas/rcar-csi2.c | 25 +++++++++++++++---------- >> 1 file changed, 15 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c >> index 7305cc4a04cb..158fa447e668 100644 >> --- a/drivers/media/platform/renesas/rcar-csi2.c >> +++ b/drivers/media/platform/renesas/rcar-csi2.c >> @@ -1822,20 +1822,12 @@ static int rcsi2_start(struct rcar_csi2 *priv, struct v4l2_subdev_state *state) >> return ret; >> } >> >> - ret = v4l2_subdev_enable_streams(priv->remote, priv->remote_pad, >> - BIT_ULL(0)); >> - if (ret) { >> - rcsi2_enter_standby(priv); >> - return ret; >> - } >> - >> return 0; >> } >> >> static void rcsi2_stop(struct rcar_csi2 *priv) >> { >> rcsi2_enter_standby(priv); >> - v4l2_subdev_disable_streams(priv->remote, priv->remote_pad, BIT_ULL(0)); >> } >> >> static int rcsi2_enable_streams(struct v4l2_subdev *sd, >> @@ -1857,6 +1849,14 @@ static int rcsi2_enable_streams(struct v4l2_subdev *sd, >> return ret; >> } >> >> + ret = v4l2_subdev_enable_streams(priv->remote, priv->remote_pad, >> + BIT_ULL(0)); >> + if (ret) { >> + if (priv->stream_count == 0) >> + rcsi2_stop(priv); >> + return ret; >> + } >> + >> priv->stream_count += 1; >> >> return ret; >> @@ -1867,7 +1867,7 @@ static int rcsi2_disable_streams(struct v4l2_subdev *sd, >> u32 source_pad, u64 source_streams_mask) >> { >> struct rcar_csi2 *priv = sd_to_csi2(sd); >> - int ret = 0; >> + int ret; >> >> if (source_streams_mask != 1) >> return -EINVAL; >> @@ -1878,9 +1878,14 @@ static int rcsi2_disable_streams(struct v4l2_subdev *sd, >> if (priv->stream_count == 1) >> rcsi2_stop(priv); >> >> + ret = v4l2_subdev_disable_streams(priv->remote, priv->remote_pad, >> + BIT_ULL(0)); >> + if (ret) >> + return ret; >> + >> priv->stream_count -= 1; >> >> - return ret; >> + return 0; >> } > > rcsi2_irq_thread() also calls rcsi2_stop(), followed by rcsi2_start(). > This is to handle errors reported by the AFIFO_OF, ERRSOTHS and > ERRSOTSYNCHS interrupts. If the source isn't restarted, such an attempt > to recover from errors will likely fail. On the other hand, restarting > the source will likely not lead to great results either. Indeed. I think for single-stream use cases the behavior should still be the same, but for multi-stream use, any enabled stream will keep the csi2 enabled. This kind of error handling sounds a bit fragile. If a restart helps, don't we need to restart the whole pipeline, not just from csi2-rx upwards? Or is it guaranteed that the ISP/CS and VIN will continue working? Did this work earlier with the custom VC based routing? Tomi > Error handling was introduced in > > commit 4ab44ff0841b9a825f9875623d24809d29e37a10 > Author: Niklas Söderlund > Date: Thu Apr 11 16:30:58 2019 -0400 > > media: rcar-csi2: restart CSI-2 link if error is detected > > Restart the CSI-2 link if the CSI-2 receiver detects an error during > reception. The driver did nothing when a link error happened and the > data flow simply stopped without the user knowing why. > > Change the driver to try and recover from errors by restarting the link > and informing the user that something is not right. For obvious reasons > it's not possible to recover from all errors (video source disconnected > for example) but in such cases the user is at least informed of the > error and the same behavior of the stopped data flow is retained. > > Niklas, do you recall anything about the errors you saw ?