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 DBA0615CD51; Wed, 24 Apr 2024 13:50:18 +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=1713966621; cv=none; b=QAMXHMjG/e1pv4vMNHxQo33Hc1T2uGQ5OmA/uduHrJudodcvRE5JVB0uHJD9OePw7yDk0HpHrk9vkKRxkd4exiaPoqotX5IPOuI4kmY1sMqh8ZZOnPEZLyJN70aYVcX+WK+cjr5BNmmiY5leX9JUhD06edGHQM2Ty5PG6d/3s74= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713966621; c=relaxed/simple; bh=q/ExYKiFEVjwmIVjlK9eTcgI5PfKZml0hLK7Keoic9A=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=HVEviR3OfFKY4yWyHlCT/hUXlfRKP7SoY5IaWwZxCThDM0caXHOMS3pos64WdSCmqKefzuCKz4aQXKOV0coOuPH9mRpBgj4TBm3dSVGL885B5jRHBwFZnCs47Hpn8kzj913dNU+euWt+xZfgDq7Y442UPcYyqmM6Lkpkm+MaVr4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (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=V3VlPNq9; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (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="V3VlPNq9" Received: from [192.168.88.20] (91-154-34-181.elisa-laajakaista.fi [91.154.34.181]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id C04CEB1; Wed, 24 Apr 2024 15:49:24 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1713966565; bh=q/ExYKiFEVjwmIVjlK9eTcgI5PfKZml0hLK7Keoic9A=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=V3VlPNq9EIaDrItMBVEWs7vMifV8cFm5j+0ptQU7R4HqWZAGPvQH/gjGVkeHgN+Fy cEHUXVmN4rSOtVbUsloNS4ezhdqc2Suw9qB3eC683NN9jDYGtTkWV74tmhVxrmCdMW 4fj+6t2YZX68LvuzAZGWbTuGHz+d//D6bHZe5Hn8= Message-ID: <552f33b1-02b5-4fc4-98d2-15da4ddf136a@ideasonboard.com> Date: Wed, 24 Apr 2024 16:50:14 +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 09/10] media: subdev: Support single-stream case in v4l2_subdev_enable/disable_streams() To: Laurent Pinchart Cc: Mauro Carvalho Chehab , Hans Verkuil , Sakari Ailus , Umang Jain , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org References: <20240416-enable-streams-impro-v5-0-bd5fcea49388@ideasonboard.com> <20240416-enable-streams-impro-v5-9-bd5fcea49388@ideasonboard.com> <20240419153603.GE12651@pendragon.ideasonboard.com> <7ed5e8cf-2bcc-4d4c-a1dc-17592b5909c0@ideasonboard.com> <20240424130922.GG18608@pendragon.ideasonboard.com> <6e2eeba1-236f-481e-9e35-460f26549698@ideasonboard.com> <20240424131733.GH18608@pendragon.ideasonboard.com> Content-Language: en-US From: Tomi Valkeinen Autocrypt: addr=tomi.valkeinen@ideasonboard.com; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 24/04/2024 16:17, Laurent Pinchart wrote: > On Wed, Apr 24, 2024 at 04:11:36PM +0300, Tomi Valkeinen wrote: >> On 24/04/2024 16:09, Laurent Pinchart wrote: >>> On Wed, Apr 24, 2024 at 04:05:31PM +0300, Tomi Valkeinen wrote: >>>> On 19/04/2024 18:36, Laurent Pinchart wrote: >>>>> On Tue, Apr 16, 2024 at 04:55:12PM +0300, Tomi Valkeinen wrote: >>>>>> At the moment the v4l2_subdev_enable/disable_streams() functions call >>>>>> fallback helpers to handle the case where the subdev only implements >>>>>> .s_stream(), and the main function handles the case where the subdev >>>>>> implements streams (V4L2_SUBDEV_FL_STREAMS, which implies >>>>>> .enable/disable_streams()). >>>>>> >>>>>> What is missing is support for subdevs which do not implement streams >>>>>> support, but do implement .enable/disable_streams(). Example cases of >>>>>> these subdevices are single-stream cameras, where using >>>>>> .enable/disable_streams() is not required but helps us remove the users >>>>>> of the legacy .s_stream(), and subdevices with multiple source pads (but >>>>>> single stream per pad), where .enable/disable_streams() allows the >>>>>> subdevice to control the enable/disable state per pad. >>>>>> >>>>>> The two single-streams cases (.s_stream() and .enable/disable_streams()) >>>>>> are very similar, and with small changes we can change the >>>>>> v4l2_subdev_enable/disable_streams() functions to support all three >>>>>> cases, without needing separate fallback functions. >>>>>> >>>>>> A few potentially problematic details, though: >>>>>> >>>>>> - For the single-streams cases we use sd->enabled_pads field, which >>>>>> limits the number of pads for the subdevice to 64. For simplicity I >>>>>> added the check for this limitation to the beginning of the function, >>>>>> and it also applies to the streams case. >>>>>> >>>>>> - The fallback functions only allowed the target pad to be a source pad. >>>>>> It is not very clear to me why this check was needed, but it was not >>>>>> needed in the streams case. However, I doubt the >>>>>> v4l2_subdev_enable/disable_streams() code has ever been tested with >>>>>> sink pads, so to be on the safe side, I added the same check >>>>>> to the v4l2_subdev_enable/disable_streams() functions. >>>>>> >>>>> >>>>> Now that v4l2_subdev_enable_streams() is usable by (almost) every >>>>> driver, should we update documentation to indicate that manual calls to >>>>> .s_stream() should be avoided ? >>>> >>>> How about: >>>> >>>> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h >>>> index dabe1b5dfe4a..f52bb790773c 100644 >>>> --- a/include/media/v4l2-subdev.h >>>> +++ b/include/media/v4l2-subdev.h >>>> @@ -450,6 +450,11 @@ enum v4l2_subdev_pre_streamon_flags { >>>> * already started or stopped subdev. Also see call_s_stream wrapper in >>>> * v4l2-subdev.c. >>>> * >>>> + * New drivers should instead implement &v4l2_subdev_pad_ops.enable_streams >>>> + * and &v4l2_subdev_pad_ops.disable_streams operations, and use >>>> + * v4l2_subdev_s_stream_helper for the &v4l2_subdev_video_ops.s_stream >>>> + * operation to support legacy users.A >>>> + * >>> >>> Add >>> >>> * Drivers should also not call the .s_stream() subdev operation directly, >>> * but use the v4l2_subdev_enable_streams() and >>> * v4l2_subdev_disable_streams() helpers. >>> >>>> * @g_pixelaspect: callback to return the pixelaspect ratio. >>>> * >>>> * @s_dv_timings: Set custom dv timings in the sub device. This is used >>>> >>>> >>>> Although now that I think about it, can we "ever" get rid of s_stream? >>>> enable_streams is only usable if the subdev has pads. >>> >>> Do we have pad-less subdevs that can stream ? >> >> Probably not, but isn't s_stream used to enable any type of subdev? Or >> is there a different op to power on padless subdevs? > > .s_stream() is supposed to start/stop streaming, and you can't really > have streams without pads, as they have to come from/go somewhere. Ok. I was under the impression that .s_stream() is also used to enable non-streaming subdevs when the pipeline's streaming is started. If that's not the case, I'll update the doc. Tomi >>>> If that's the >>>> case, the text above should probably clarify when one should continue >>>> using s_stream. >>>> >>>>>> Signed-off-by: Tomi Valkeinen >>>>>> --- >>>>>> drivers/media/v4l2-core/v4l2-subdev.c | 187 ++++++++++++++-------------------- >>>>>> 1 file changed, 79 insertions(+), 108 deletions(-) >>>>>> >>>>>> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c >>>>>> index e45fd42da1e3..10406acfb9d0 100644 >>>>>> --- a/drivers/media/v4l2-core/v4l2-subdev.c >>>>>> +++ b/drivers/media/v4l2-core/v4l2-subdev.c >>>>>> @@ -2106,6 +2106,13 @@ static void v4l2_subdev_collect_streams(struct v4l2_subdev *sd, >>>>>> u64 *found_streams, >>>>>> u64 *enabled_streams) >>>>>> { >>>>>> + if (!(sd->flags & V4L2_SUBDEV_FL_STREAMS)) { >>>>>> + *found_streams = BIT_ULL(0); >>>>>> + *enabled_streams = >>>>>> + (sd->enabled_pads & BIT_ULL(pad)) ? BIT_ULL(0) : 0; >>>>>> + return; >>>>>> + } >>>>>> + >>>>>> *found_streams = 0; >>>>>> *enabled_streams = 0; >>>>>> >>>>>> @@ -2127,6 +2134,14 @@ static void v4l2_subdev_set_streams_enabled(struct v4l2_subdev *sd, >>>>>> u32 pad, u64 streams_mask, >>>>>> bool enabled) >>>>>> { >>>>>> + if (!(sd->flags & V4L2_SUBDEV_FL_STREAMS)) { >>>>>> + if (enabled) >>>>>> + sd->enabled_pads |= BIT_ULL(pad); >>>>>> + else >>>>>> + sd->enabled_pads &= ~BIT_ULL(pad); >>>>>> + return; >>>>>> + } >>>>>> + >>>>>> for (unsigned int i = 0; i < state->stream_configs.num_configs; ++i) { >>>>>> struct v4l2_subdev_stream_config *cfg = >>>>>> &state->stream_configs.configs[i]; >>>>>> @@ -2136,51 +2151,6 @@ static void v4l2_subdev_set_streams_enabled(struct v4l2_subdev *sd, >>>>>> } >>>>>> } >>>>>> >>>>>> -static int v4l2_subdev_enable_streams_fallback(struct v4l2_subdev *sd, u32 pad, >>>>>> - u64 streams_mask) >>>>>> -{ >>>>>> - struct device *dev = sd->entity.graph_obj.mdev->dev; >>>>>> - int ret; >>>>>> - >>>>>> - /* >>>>>> - * The subdev doesn't implement pad-based stream enable, fall back >>>>>> - * to the .s_stream() operation. >>>>>> - */ >>>>>> - if (!(sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE)) >>>>>> - return -EOPNOTSUPP; >>>>>> - >>>>>> - /* >>>>>> - * .s_stream() means there is no streams support, so the only allowed >>>>>> - * stream is the implicit stream 0. >>>>>> - */ >>>>>> - if (streams_mask != BIT_ULL(0)) >>>>>> - return -EOPNOTSUPP; >>>>>> - >>>>>> - /* >>>>>> - * We use a 64-bit bitmask for tracking enabled pads, so only subdevices >>>>>> - * with 64 pads or less can be supported. >>>>>> - */ >>>>>> - if (pad >= sizeof(sd->enabled_pads) * BITS_PER_BYTE) >>>>>> - return -EOPNOTSUPP; >>>>>> - >>>>>> - if (sd->enabled_pads & BIT_ULL(pad)) { >>>>>> - dev_dbg(dev, "pad %u already enabled on %s\n", >>>>>> - pad, sd->entity.name); >>>>>> - return -EALREADY; >>>>>> - } >>>>>> - >>>>>> - /* Start streaming when the first pad is enabled. */ >>>>>> - if (!sd->enabled_pads) { >>>>>> - ret = v4l2_subdev_call(sd, video, s_stream, 1); >>>>>> - if (ret) >>>>>> - return ret; >>>>>> - } >>>>>> - >>>>>> - sd->enabled_pads |= BIT_ULL(pad); >>>>>> - >>>>>> - return 0; >>>>>> -} >>>>>> - >>>>>> int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> u64 streams_mask) >>>>>> { >>>>>> @@ -2189,21 +2159,33 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> bool already_streaming; >>>>>> u64 enabled_streams; >>>>>> u64 found_streams; >>>>>> + bool use_s_stream; >>>>>> int ret; >>>>>> >>>>>> /* A few basic sanity checks first. */ >>>>>> if (pad >= sd->entity.num_pads) >>>>>> return -EINVAL; >>>>>> >>>>>> + if (!(sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE)) >>>>>> + return -EOPNOTSUPP; >>>>>> + >>>>>> + /* >>>>>> + * We use a 64-bit bitmask for tracking enabled pads, so only subdevices >>>>>> + * with 64 pads or less can be supported. >>>>>> + */ >>>>>> + if (pad >= sizeof(sd->enabled_pads) * BITS_PER_BYTE) >>>>>> + return -EOPNOTSUPP; >>>>>> + >>>>>> if (!streams_mask) >>>>>> return 0; >>>>>> >>>>>> /* Fallback on .s_stream() if .enable_streams() isn't available. */ >>>>>> - if (!v4l2_subdev_has_op(sd, pad, enable_streams)) >>>>>> - return v4l2_subdev_enable_streams_fallback(sd, pad, >>>>>> - streams_mask); >>>>>> + use_s_stream = !v4l2_subdev_has_op(sd, pad, enable_streams); >>>>>> >>>>>> - state = v4l2_subdev_lock_and_get_active_state(sd); >>>>>> + if (!use_s_stream) >>>>>> + state = v4l2_subdev_lock_and_get_active_state(sd); >>>>>> + else >>>>>> + state = NULL; >>>>>> >>>>>> /* >>>>>> * Verify that the requested streams exist and that they are not >>>>>> @@ -2231,9 +2213,18 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> >>>>>> already_streaming = v4l2_subdev_is_streaming(sd); >>>>>> >>>>>> - /* Call the .enable_streams() operation. */ >>>>>> - ret = v4l2_subdev_call(sd, pad, enable_streams, state, pad, >>>>>> - streams_mask); >>>>>> + if (!use_s_stream) { >>>>>> + /* Call the .enable_streams() operation. */ >>>>>> + ret = v4l2_subdev_call(sd, pad, enable_streams, state, pad, >>>>>> + streams_mask); >>>>>> + } else { >>>>>> + /* Start streaming when the first pad is enabled. */ >>>>>> + if (!already_streaming) >>>>>> + ret = v4l2_subdev_call(sd, video, s_stream, 1); >>>>>> + else >>>>>> + ret = 0; >>>>>> + } >>>>>> + >>>>>> if (ret) { >>>>>> dev_dbg(dev, "enable streams %u:%#llx failed: %d\n", pad, >>>>>> streams_mask, ret); >>>>>> @@ -2243,34 +2234,32 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> /* Mark the streams as enabled. */ >>>>>> v4l2_subdev_set_streams_enabled(sd, state, pad, streams_mask, true); >>>>> >>>>> state gets set to a non-null value above if the subdev has an >>>>> enable_streams operation, while in v4l2_subdev_set_streams_enabled(), >>>> >>>> That's not quite true, v4l2_subdev_lock_and_get_active_state() returns >>>> NULL if there's no state. If the driver has .enable_streams but no >>>> subdev-state, we'll have NULL state. But is that a driver bug? Probably, >>>> although I'm not quite sure. Whereas V4L2_SUBDEV_FL_STREAMS without >>>> state is a driver bug. >>>> >>>>> you use it if the V4L2_SUBDEV_FL_STREAMS flag is set. The second >>>>> condition is a subset of the first one, so it should be safe now, but I >>>>> wonder if we're at risk of crashes in the future when reworking the >>>>> code. I'm probably worrying needlessly. >>>> >>>> I agree that this is a bit messy. We have multiple different scenarios >>>> which we handle in the same functions, and it's somewhat unclear what >>>> op/state/flag combinations the drivers are allowed to have and what not. >>>> >>>> I could add a !state check here, and then use sd->enabled_pads. But that >>>> doesn't feel correct, and I think it's just better to crash and then fix >>>> it if we end up there. >>>> >>>>>> >>>>>> - if (!already_streaming) >>>>>> + if (!use_s_stream && !already_streaming) >>>>>> v4l2_subdev_enable_privacy_led(sd); >>>>> >>>>> Once everybody switches to v4l2_subdev_enable_streams() (am I dreaming?) >>>>> we should move LED handling from the .s_stream() wrapper to here for the >>>>> fallback case too. How about a TODO comment ? >>>> >>>> Let's get back to this after we figure out if s_stream can ever be removed. >>>> >>>>>> >>>>>> done: >>>>>> - v4l2_subdev_unlock_state(state); >>>>>> + if (!use_s_stream) >>>>> >>>>> if (state) >>>>> >>>>> would be better I think. >>>> >>>> We get the state and state lock if (!use_s_stream), so I think it makes >>>> sense to use the same condition when unlocking to be symmetric. I'm sure >>>> I can be convinced to use if (state) too, though =). >>>> >>>>>> + v4l2_subdev_unlock_state(state); >>>>>> >>>>>> return ret; >>>>>> } >>>>>> EXPORT_SYMBOL_GPL(v4l2_subdev_enable_streams); >>>>>> >>>>>> -static int v4l2_subdev_disable_streams_fallback(struct v4l2_subdev *sd, u32 pad, >>>>>> - u64 streams_mask) >>>>>> +int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> + u64 streams_mask) >>>>>> { >>>>>> struct device *dev = sd->entity.graph_obj.mdev->dev; >>>>>> + struct v4l2_subdev_state *state; >>>>>> + u64 enabled_streams; >>>>>> + u64 found_streams; >>>>>> + bool use_s_stream; >>>>>> int ret; >>>>>> >>>>>> - /* >>>>>> - * If the subdev doesn't implement pad-based stream enable, fall back >>>>>> - * to the .s_stream() operation. >>>>>> - */ >>>>>> - if (!(sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE)) >>>>>> - return -EOPNOTSUPP; >>>>>> + /* A few basic sanity checks first. */ >>>>>> + if (pad >= sd->entity.num_pads) >>>>>> + return -EINVAL; >>>>>> >>>>>> - /* >>>>>> - * .s_stream() means there is no streams support, so the only allowed >>>>>> - * stream is the implicit stream 0. >>>>>> - */ >>>>>> - if (streams_mask != BIT_ULL(0)) >>>>>> + if (!(sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE)) >>>>>> return -EOPNOTSUPP; >>>>>> >>>>>> /* >>>>>> @@ -2280,46 +2269,16 @@ static int v4l2_subdev_disable_streams_fallback(struct v4l2_subdev *sd, u32 pad, >>>>>> if (pad >= sizeof(sd->enabled_pads) * BITS_PER_BYTE) >>>>>> return -EOPNOTSUPP; >>>>>> >>>>>> - if (!(sd->enabled_pads & BIT_ULL(pad))) { >>>>>> - dev_dbg(dev, "pad %u already disabled on %s\n", >>>>>> - pad, sd->entity.name); >>>>>> - return -EALREADY; >>>>>> - } >>>>>> - >>>>>> - /* Stop streaming when the last streams are disabled. */ >>>>>> - if (!(sd->enabled_pads & ~BIT_ULL(pad))) { >>>>>> - ret = v4l2_subdev_call(sd, video, s_stream, 0); >>>>>> - if (ret) >>>>>> - return ret; >>>>>> - } >>>>>> - >>>>>> - sd->enabled_pads &= ~BIT_ULL(pad); >>>>>> - >>>>>> - return 0; >>>>>> -} >>>>>> - >>>>>> -int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> - u64 streams_mask) >>>>>> -{ >>>>>> - struct device *dev = sd->entity.graph_obj.mdev->dev; >>>>>> - struct v4l2_subdev_state *state; >>>>>> - u64 enabled_streams; >>>>>> - u64 found_streams; >>>>>> - int ret; >>>>>> - >>>>>> - /* A few basic sanity checks first. */ >>>>>> - if (pad >= sd->entity.num_pads) >>>>>> - return -EINVAL; >>>>>> - >>>>>> if (!streams_mask) >>>>>> return 0; >>>>>> >>>>>> /* Fallback on .s_stream() if .disable_streams() isn't available. */ >>>>>> - if (!v4l2_subdev_has_op(sd, pad, disable_streams)) >>>>>> - return v4l2_subdev_disable_streams_fallback(sd, pad, >>>>>> - streams_mask); >>>>>> + use_s_stream = !v4l2_subdev_has_op(sd, pad, disable_streams); >>>>>> >>>>>> - state = v4l2_subdev_lock_and_get_active_state(sd); >>>>>> + if (!use_s_stream) >>>>>> + state = v4l2_subdev_lock_and_get_active_state(sd); >>>>>> + else >>>>>> + state = NULL; >>>>>> >>>>>> /* >>>>>> * Verify that the requested streams exist and that they are not >>>>>> @@ -2345,9 +2304,19 @@ int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> >>>>>> dev_dbg(dev, "disable streams %u:%#llx\n", pad, streams_mask); >>>>>> >>>>>> - /* Call the .disable_streams() operation. */ >>>>>> - ret = v4l2_subdev_call(sd, pad, disable_streams, state, pad, >>>>>> - streams_mask); >>>>>> + if (!use_s_stream) { >>>>>> + /* Call the .disable_streams() operation. */ >>>>>> + ret = v4l2_subdev_call(sd, pad, disable_streams, state, pad, >>>>>> + streams_mask); >>>>>> + } else { >>>>>> + /* Stop streaming when the last streams are disabled. */ >>>>>> + >>>>>> + if (!(sd->enabled_pads & ~BIT_ULL(pad))) >>>>>> + ret = v4l2_subdev_call(sd, video, s_stream, 0); >>>>>> + else >>>>>> + ret = 0; >>>>>> + } >>>>>> + >>>>>> if (ret) { >>>>>> dev_dbg(dev, "disable streams %u:%#llx failed: %d\n", pad, >>>>>> streams_mask, ret); >>>>>> @@ -2357,10 +2326,12 @@ int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad, >>>>>> v4l2_subdev_set_streams_enabled(sd, state, pad, streams_mask, false); >>>>>> >>>>>> done: >>>>>> - if (!v4l2_subdev_is_streaming(sd)) >>>>>> - v4l2_subdev_disable_privacy_led(sd); >>>>>> + if (!use_s_stream) { >>>>>> + if (!v4l2_subdev_is_streaming(sd)) >>>>>> + v4l2_subdev_disable_privacy_led(sd); >>>>> >>>>> Do we want to disable the privacy LED on failure in all cases, in >>>>> particular when the .s_stream() or .disable_streams() operations are not >>>>> even called ? >>>>> >>>>> And now that I wrote that, I realize the !v4l2_subdev_is_streaming() >>>>> condition will not be true if the operations failed, so it should be >>>>> fine. >>>>> >>>>> Reviewed-by: Laurent Pinchart >>>>> >>>>>> >>>>>> - v4l2_subdev_unlock_state(state); >>>>>> + v4l2_subdev_unlock_state(state); >>>>>> + } >>>>>> >>>>>> return ret; >>>>>> } >>>>>> >