Linux-Media Archive mirror
 help / color / mirror / Atom feed
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Jacopo Mondi <jacopo+renesas@jmondi.org>
Cc: tomi.valkeinen@ideasonboard.com, sakari.ailus@linux.intel.com,
	niklas.soderlund@ragnatech.se, kieran.bingham@ideasonboard.com,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Hans Verkuil <hverkuil-cisco@xs4all.nl>,
	linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org
Subject: Re: [PATCH v4 3/6] media: max9286: Use enabled routes to calculate pixelrate
Date: Fri, 17 Dec 2021 04:29:50 +0200	[thread overview]
Message-ID: <Ybv2HilpOKyP/wE4@pendragon.ideasonboard.com> (raw)
In-Reply-To: <20211216174746.147233-4-jacopo+renesas@jmondi.org>

Hi Jacopo,

Thank you for the patch.

On Thu, Dec 16, 2021 at 06:47:43PM +0100, Jacopo Mondi wrote:
> Now that the device supports routing, use the enabled routes instead
> of the connected sources to compute the output pixel rate.
> 
> To do so, update the route_mask after a set_routing() call with the
> ACTIVE format, and re-calculate the pixel rate just after.
> 
> At the same time, start and stop only the enabled routes at s_stream()
> time.
> 
> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> ---
>  drivers/media/i2c/max9286.c | 63 ++++++++++++++++++++++++++++++-------
>  1 file changed, 51 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c
> index eb76acdb2cd9..1395eb783dc0 100644
> --- a/drivers/media/i2c/max9286.c
> +++ b/drivers/media/i2c/max9286.c
> @@ -188,8 +188,11 @@ struct max9286_priv {
>  	struct v4l2_async_notifier notifier;
>  };
>  
> +#define to_index(priv, source) ((source) - &(priv)->sources[0])
> +
>  static struct max9286_source *next_source(struct max9286_priv *priv,
> -					  struct max9286_source *source)
> +					  struct max9286_source *source,
> +					  bool routed)
>  {
>  	if (!source)
>  		source = &priv->sources[0];
> @@ -197,17 +200,27 @@ static struct max9286_source *next_source(struct max9286_priv *priv,
>  		source++;
>  
>  	for (; source < &priv->sources[MAX9286_NUM_GMSL]; source++) {
> -		if (source->fwnode)
> +		unsigned int index = to_index(priv, source);
> +
> +		if (!source->fwnode)
> +			continue;
> +
> +		/*
> +		 * Careful here! A very unfortunate call to set_routing() can
> +		 * change priv->route_mask behind our back!
> +		 */

This seems error-prone. I wonder if we could instead remove route_mask
completely, and compute it as .s_stream(1) time by walking the routes
from the state. That would avoid storing state information in
max9286_priv.

The downside is that we'll have to pass the route mask down to functions
called by max9286_s_stream(). At some point in the future, I'd like to
see support for subclassing the subdev state in subdev drivers, at which
point we will be able to cache the route_mask in the subclassed state
when configuring routing, and reusing the cached value when starting the
streams.

> +		if (!routed || priv->route_mask & BIT(index))
>  			return source;
>  	}
>  
>  	return NULL;
>  }
>  
> -#define for_each_source(priv, source) \
> -	for ((source) = NULL; ((source) = next_source((priv), (source))); )
> +#define for_each_route(priv, source) \
> +	for ((source) = NULL; ((source) = next_source((priv), (source), true)); )
>  
> -#define to_index(priv, source) ((source) - &(priv)->sources[0])
> +#define for_each_source(priv, source) \
> +	for ((source) = NULL; ((source) = next_source((priv), (source), false)); )
>  
>  static inline struct max9286_priv *sd_to_max9286(struct v4l2_subdev *sd)
>  {
> @@ -409,7 +422,7 @@ static int max9286_check_video_links(struct max9286_priv *priv)
>  		if (ret < 0)
>  			return -EIO;
>  
> -		if ((ret & MAX9286_VIDEO_DETECT_MASK) == priv->source_mask)
> +		if ((ret & MAX9286_VIDEO_DETECT_MASK) == priv->route_mask)
>  			break;
>  
>  		usleep_range(350, 500);
> @@ -493,9 +506,10 @@ static int max9286_check_config_link(struct max9286_priv *priv,
>  static int max9286_set_pixelrate(struct max9286_priv *priv)
>  {
>  	struct max9286_source *source = NULL;
> +	unsigned int num_routes = 0;
>  	u64 pixelrate = 0;
>  
> -	for_each_source(priv, source) {
> +	for_each_route(priv, source) {
>  		struct v4l2_ctrl *ctrl;
>  		u64 source_rate = 0;
>  
> @@ -516,6 +530,8 @@ static int max9286_set_pixelrate(struct max9286_priv *priv)
>  				"Unable to calculate pixel rate\n");
>  			return -EINVAL;
>  		}
> +
> +		num_routes++;
>  	}
>  
>  	if (!pixelrate) {
> @@ -529,7 +545,7 @@ static int max9286_set_pixelrate(struct max9286_priv *priv)
>  	 * by the number of available sources.
>  	 */
>  	return v4l2_ctrl_s_ctrl_int64(priv->pixelrate,
> -				      pixelrate * priv->nsources);
> +				      pixelrate * num_routes);
>  }
>  
>  static int max9286_notify_bound(struct v4l2_async_notifier *notifier,
> @@ -691,8 +707,8 @@ static int max9286_s_stream(struct v4l2_subdev *sd, int enable)
>  		 */
>  		max9286_i2c_mux_open(priv);
>  
> -		/* Start all cameras. */
> -		for_each_source(priv, source) {
> +		/* Start cameras. */
> +		for_each_route(priv, source) {
>  			ret = v4l2_subdev_call(source->sd, video, s_stream, 1);
>  			if (ret)
>  				return ret;
> @@ -733,8 +749,8 @@ static int max9286_s_stream(struct v4l2_subdev *sd, int enable)
>  	} else {
>  		max9286_write(priv, 0x15, MAX9286_VCTYPE | MAX9286_0X15_RESV);
>  
> -		/* Stop all cameras. */
> -		for_each_source(priv, source)
> +		/* Stop cameras. */
> +		for_each_route(priv, source)
>  			v4l2_subdev_call(source->sd, video, s_stream, 0);
>  
>  		max9286_i2c_mux_close(priv);
> @@ -912,6 +928,29 @@ static int max9286_set_routing(struct v4l2_subdev *sd,
>  	v4l2_subdev_lock_state(state);
>  
>  	ret = _max9286_set_routing(sd, state, routing);
> +	if (ret)
> +		goto out;
> +
> +	if (which == V4L2_SUBDEV_FORMAT_TRY)
> +		goto out;
> +
> +	/*
> +	 * Update the active routes mask and the pixel rate according to the
> +	 * routed sources.
> +	 */
> +	priv->route_mask = 0;
> +	for (i = 0; i < routing->num_routes; ++i) {
> +		struct v4l2_subdev_route *route = &routing->routes[i];
> +
> +		if (!(route->flags & V4L2_SUBDEV_ROUTE_FL_ACTIVE))
> +			continue;
> +
> +		priv->route_mask |= BIT(route->sink_pad);
> +	}
> +
> +	max9286_set_pixelrate(priv);
> +
> +out:
>  	v4l2_subdev_unlock_state(state);
>  
>  	return ret;

-- 
Regards,

Laurent Pinchart

  reply	other threads:[~2021-12-17  2:29 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-16 17:47 [PATCH v4 0/6] media: max9286: Add multiplexed streams support Jacopo Mondi
2021-12-16 17:47 ` [PATCH v4 1/6] media: max9286: Add support for v4l2_subdev_state Jacopo Mondi
2021-12-16 18:33   ` Laurent Pinchart
2021-12-16 17:47 ` [PATCH v4 2/6] media: max9286: Implement set_routing Jacopo Mondi
2021-12-17  1:56   ` Laurent Pinchart
2021-12-17  2:18     ` Laurent Pinchart
2021-12-17  2:24       ` Laurent Pinchart
2021-12-17 13:28         ` Jacopo Mondi
2021-12-16 17:47 ` [PATCH v4 3/6] media: max9286: Use enabled routes to calculate pixelrate Jacopo Mondi
2021-12-17  2:29   ` Laurent Pinchart [this message]
2021-12-17 13:32     ` Jacopo Mondi
2021-12-16 17:47 ` [PATCH v4 4/6] media: max9286: Use routes to configure link order Jacopo Mondi
2021-12-17  2:35   ` Laurent Pinchart
2021-12-17 13:38     ` Jacopo Mondi
2021-12-16 17:47 ` [PATCH v4 5/6] media: max9286: Move format to subdev state Jacopo Mondi
2021-12-17  2:40   ` Laurent Pinchart
2021-12-17  3:09     ` Laurent Pinchart
2021-12-17 14:11       ` Jacopo Mondi
2024-05-09 13:11         ` Laurent Pinchart
2021-12-16 17:47 ` [PATCH v4 6/6] media: max9286: Implement get_frame_desc() Jacopo Mondi
2021-12-17  2:45   ` Laurent Pinchart
2021-12-17 14:12     ` Jacopo Mondi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Ybv2HilpOKyP/wE4@pendragon.ideasonboard.com \
    --to=laurent.pinchart@ideasonboard.com \
    --cc=hverkuil-cisco@xs4all.nl \
    --cc=jacopo+renesas@jmondi.org \
    --cc=kieran.bingham@ideasonboard.com \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-renesas-soc@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=niklas.soderlund@ragnatech.se \
    --cc=sakari.ailus@linux.intel.com \
    --cc=tomi.valkeinen@ideasonboard.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).