diff mbox series

[v2,2/3] media: i2c: ov772x: Add support for BT656 mode

Message ID 1596454753-13612-3-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive)
State New, archived
Headers show
Series media: i2c: ov772x: Enable BT656 mode and test pattern support | expand

Commit Message

Lad Prabhakar Aug. 3, 2020, 11:39 a.m. UTC 
Add support to read the bus-type and enable BT656 mode if needed.

The driver defaults to parallel mode if bus-type is not specified in DT.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
 drivers/media/i2c/ov772x.c | 40 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

Comments

Jacopo Mondi Aug. 6, 2020, 2:45 p.m. UTC | #1 
On Mon, Aug 03, 2020 at 12:39:12PM +0100, Lad Prabhakar wrote:
> Add support to read the bus-type and enable BT656 mode if needed.
>
> The driver defaults to parallel mode if bus-type is not specified in DT.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
>  drivers/media/i2c/ov772x.c | 40 ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
>
> diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> index 2cc6a678069a..2de9248e3689 100644
> --- a/drivers/media/i2c/ov772x.c
> +++ b/drivers/media/i2c/ov772x.c
> @@ -31,6 +31,7 @@
>  #include <media/v4l2-ctrls.h>
>  #include <media/v4l2-device.h>
>  #include <media/v4l2-event.h>
> +#include <media/v4l2-fwnode.h>
>  #include <media/v4l2-image-sizes.h>
>  #include <media/v4l2-subdev.h>
>
> @@ -434,6 +435,7 @@ struct ov772x_priv {
>  #ifdef CONFIG_MEDIA_CONTROLLER
>  	struct media_pad pad;
>  #endif
> +	struct v4l2_fwnode_endpoint ep;
>  };
>
>  /*
> @@ -574,6 +576,7 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
>  {
>  	struct i2c_client *client = v4l2_get_subdevdata(sd);
>  	struct ov772x_priv *priv = to_ov772x(sd);
> +	unsigned int val;
>  	int ret = 0;
>
>  	mutex_lock(&priv->lock);
> @@ -581,6 +584,22 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
>  	if (priv->streaming == enable)
>  		goto done;
>
> +	if (priv->ep.bus_type == V4L2_MBUS_BT656 && enable) {
> +		ret = regmap_read(priv->regmap, COM7, &val);
> +		if (ret)
> +			goto done;
> +		val |= ITU656_ON_OFF;
> +		ret = regmap_write(priv->regmap, COM7, val);
> +	} else if (priv->ep.bus_type == V4L2_MBUS_BT656 && !enable) {

is the !enable intentional ? (sorry I don't have access to the sensor
manual). If not, see below:

> +		ret = regmap_read(priv->regmap, COM7, &val);
> +		if (ret)
> +			goto done;
> +		val &= ~ITU656_ON_OFF;
> +		ret = regmap_write(priv->regmap, COM7, val);
> +	}
> +	if (ret)
> +		goto done;

Could you write this as:

static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct ov772x_priv *priv = to_ov772x(sd);
	int ret = 0;

	mutex_lock(&priv->lock);

	if (priv->streaming == enable)
		goto done;

	if (enable) {
		ret = regmap_read(priv->regmap, COM7, &val);
		if (ret)
			goto done;

	        if (priv->ep.bus_type == V4L2_MBUS_BT656)
		        val |= ITU656_ON_OFF;
                else /* if you accept my suggestion to consider othe
                        bus types as errors */
		        val &= ~ITU656_ON_OFF;

		ret = regmap_write(priv->regmap, COM7, val);
		if (ret)
			goto done;

		dev_dbg(&client->dev, "format %d, win %s\n",
			priv->cfmt->code, priv->win->name);
	}

	ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
				 enable ? 0 : SOFT_SLEEP_MODE);
	if (ret)
		goto done;
	priv->streaming = enable;

done:
	mutex_unlock(&priv->lock);

	return ret;
}


>  	ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
>  				 enable ? 0 : SOFT_SLEEP_MODE);
>  	if (ret)
> @@ -1354,6 +1373,7 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
>
>  static int ov772x_probe(struct i2c_client *client)
>  {
> +	struct fwnode_handle *endpoint;
>  	struct ov772x_priv	*priv;
>  	int			ret;
>  	static const struct regmap_config ov772x_regmap_config = {
> @@ -1415,6 +1435,26 @@ static int ov772x_probe(struct i2c_client *client)
>  		goto error_clk_put;
>  	}
>
> +	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
> +						  NULL);
> +	if (!endpoint) {
> +		dev_err(&client->dev, "endpoint node not found\n");
> +		ret = -EINVAL;
> +		goto error_clk_put;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(endpoint, &priv->ep);
> +	fwnode_handle_put(endpoint);
> +	if (ret) {
> +		dev_err(&client->dev, "Could not parse endpoint\n");
> +		goto error_clk_put;
> +	}
> +
> +	/* fallback to parallel mode */
> +	if (priv->ep.bus_type != V4L2_MBUS_PARALLEL &&
> +	    priv->ep.bus_type != V4L2_MBUS_BT656)
> +		priv->ep.bus_type = V4L2_MBUS_PARALLEL;

shouldn't this be an error ? It's either the bus type has not been
specified on DT (which is fine, otherwise old DTB without that
properties will fail) and the bus identification routine implemented
in v4l2_fwnode_endpoint_parse() detected a bus type which is not
supported, hence the DT properties are wrong, and this should be an
error. If you plan to expand the parsing routine to support, say
bus-width and pclk polarity please break this out to a new function.

Thanks
   j

> +
>  	ret = ov772x_video_probe(priv);
>  	if (ret < 0)
>  		goto error_gpio_put;
> --
> 2.17.1
>
Prabhakar Aug. 10, 2020, 7:25 a.m. UTC | #2 
Hi Jacopo,

Thank you for the review.

On Thu, Aug 6, 2020 at 3:41 PM Jacopo Mondi <jacopo@jmondi.org> wrote:
>
> On Mon, Aug 03, 2020 at 12:39:12PM +0100, Lad Prabhakar wrote:
> > Add support to read the bus-type and enable BT656 mode if needed.
> >
> > The driver defaults to parallel mode if bus-type is not specified in DT.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> >  drivers/media/i2c/ov772x.c | 40 ++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 40 insertions(+)
> >
> > diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> > index 2cc6a678069a..2de9248e3689 100644
> > --- a/drivers/media/i2c/ov772x.c
> > +++ b/drivers/media/i2c/ov772x.c
> > @@ -31,6 +31,7 @@
> >  #include <media/v4l2-ctrls.h>
> >  #include <media/v4l2-device.h>
> >  #include <media/v4l2-event.h>
> > +#include <media/v4l2-fwnode.h>
> >  #include <media/v4l2-image-sizes.h>
> >  #include <media/v4l2-subdev.h>
> >
> > @@ -434,6 +435,7 @@ struct ov772x_priv {
> >  #ifdef CONFIG_MEDIA_CONTROLLER
> >       struct media_pad pad;
> >  #endif
> > +     struct v4l2_fwnode_endpoint ep;
> >  };
> >
> >  /*
> > @@ -574,6 +576,7 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
> >  {
> >       struct i2c_client *client = v4l2_get_subdevdata(sd);
> >       struct ov772x_priv *priv = to_ov772x(sd);
> > +     unsigned int val;
> >       int ret = 0;
> >
> >       mutex_lock(&priv->lock);
> > @@ -581,6 +584,22 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
> >       if (priv->streaming == enable)
> >               goto done;
> >
> > +     if (priv->ep.bus_type == V4L2_MBUS_BT656 && enable) {
> > +             ret = regmap_read(priv->regmap, COM7, &val);
> > +             if (ret)
> > +                     goto done;
> > +             val |= ITU656_ON_OFF;
> > +             ret = regmap_write(priv->regmap, COM7, val);
> > +     } else if (priv->ep.bus_type == V4L2_MBUS_BT656 && !enable) {
>
> is the !enable intentional ? (sorry I don't have access to the sensor
> manual). If not, see below:
>
> > +             ret = regmap_read(priv->regmap, COM7, &val);
> > +             if (ret)
> > +                     goto done;
> > +             val &= ~ITU656_ON_OFF;
> > +             ret = regmap_write(priv->regmap, COM7, val);
> > +     }
> > +     if (ret)
> > +             goto done;
>
> Could you write this as:
>
Agreed will do.

> static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
> {
>         struct i2c_client *client = v4l2_get_subdevdata(sd);
>         struct ov772x_priv *priv = to_ov772x(sd);
>         int ret = 0;
>
>         mutex_lock(&priv->lock);
>
>         if (priv->streaming == enable)
>                 goto done;
>
>         if (enable) {
>                 ret = regmap_read(priv->regmap, COM7, &val);
>                 if (ret)
>                         goto done;
>
>                 if (priv->ep.bus_type == V4L2_MBUS_BT656)
>                         val |= ITU656_ON_OFF;
>                 else /* if you accept my suggestion to consider othe
>                         bus types as errors */
>                         val &= ~ITU656_ON_OFF;
>
>                 ret = regmap_write(priv->regmap, COM7, val);
>                 if (ret)
>                         goto done;
>
>                 dev_dbg(&client->dev, "format %d, win %s\n",
>                         priv->cfmt->code, priv->win->name);
>         }
>
>         ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
>                                  enable ? 0 : SOFT_SLEEP_MODE);
>         if (ret)
>                 goto done;
>         priv->streaming = enable;
>
> done:
>         mutex_unlock(&priv->lock);
>
>         return ret;
> }
>
>
> >       ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
> >                                enable ? 0 : SOFT_SLEEP_MODE);
> >       if (ret)
> > @@ -1354,6 +1373,7 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
> >
> >  static int ov772x_probe(struct i2c_client *client)
> >  {
> > +     struct fwnode_handle *endpoint;
> >       struct ov772x_priv      *priv;
> >       int                     ret;
> >       static const struct regmap_config ov772x_regmap_config = {
> > @@ -1415,6 +1435,26 @@ static int ov772x_probe(struct i2c_client *client)
> >               goto error_clk_put;
> >       }
> >
> > +     endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
> > +                                               NULL);
> > +     if (!endpoint) {
> > +             dev_err(&client->dev, "endpoint node not found\n");
> > +             ret = -EINVAL;
> > +             goto error_clk_put;
> > +     }
> > +
> > +     ret = v4l2_fwnode_endpoint_parse(endpoint, &priv->ep);
> > +     fwnode_handle_put(endpoint);
> > +     if (ret) {
> > +             dev_err(&client->dev, "Could not parse endpoint\n");
> > +             goto error_clk_put;
> > +     }
> > +
> > +     /* fallback to parallel mode */
> > +     if (priv->ep.bus_type != V4L2_MBUS_PARALLEL &&
> > +         priv->ep.bus_type != V4L2_MBUS_BT656)
> > +             priv->ep.bus_type = V4L2_MBUS_PARALLEL;
>
> shouldn't this be an error ? It's either the bus type has not been
> specified on DT (which is fine, otherwise old DTB without that
> properties will fail) and the bus identification routine implemented
> in v4l2_fwnode_endpoint_parse() detected a bus type which is not
> supported, hence the DT properties are wrong, and this should be an
> error. If you plan to expand the parsing routine to support, say
> bus-width and pclk polarity please break this out to a new function.
>
Agreed.

Cheers,
Prabhakar

> Thanks
>    j
>
> > +
> >       ret = ov772x_video_probe(priv);
> >       if (ret < 0)
> >               goto error_gpio_put;
> > --
> > 2.17.1
> >
diff mbox series

Patch

diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
index 2cc6a678069a..2de9248e3689 100644
--- a/drivers/media/i2c/ov772x.c
+++ b/drivers/media/i2c/ov772x.c
@@ -31,6 +31,7 @@ 
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-event.h>
+#include <media/v4l2-fwnode.h>
 #include <media/v4l2-image-sizes.h>
 #include <media/v4l2-subdev.h>
 
@@ -434,6 +435,7 @@  struct ov772x_priv {
 #ifdef CONFIG_MEDIA_CONTROLLER
 	struct media_pad pad;
 #endif
+	struct v4l2_fwnode_endpoint ep;
 };
 
 /*
@@ -574,6 +576,7 @@  static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);
 	struct ov772x_priv *priv = to_ov772x(sd);
+	unsigned int val;
 	int ret = 0;
 
 	mutex_lock(&priv->lock);
@@ -581,6 +584,22 @@  static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
 	if (priv->streaming == enable)
 		goto done;
 
+	if (priv->ep.bus_type == V4L2_MBUS_BT656 && enable) {
+		ret = regmap_read(priv->regmap, COM7, &val);
+		if (ret)
+			goto done;
+		val |= ITU656_ON_OFF;
+		ret = regmap_write(priv->regmap, COM7, val);
+	} else if (priv->ep.bus_type == V4L2_MBUS_BT656 && !enable) {
+		ret = regmap_read(priv->regmap, COM7, &val);
+		if (ret)
+			goto done;
+		val &= ~ITU656_ON_OFF;
+		ret = regmap_write(priv->regmap, COM7, val);
+	}
+	if (ret)
+		goto done;
+
 	ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
 				 enable ? 0 : SOFT_SLEEP_MODE);
 	if (ret)
@@ -1354,6 +1373,7 @@  static const struct v4l2_subdev_ops ov772x_subdev_ops = {
 
 static int ov772x_probe(struct i2c_client *client)
 {
+	struct fwnode_handle *endpoint;
 	struct ov772x_priv	*priv;
 	int			ret;
 	static const struct regmap_config ov772x_regmap_config = {
@@ -1415,6 +1435,26 @@  static int ov772x_probe(struct i2c_client *client)
 		goto error_clk_put;
 	}
 
+	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
+						  NULL);
+	if (!endpoint) {
+		dev_err(&client->dev, "endpoint node not found\n");
+		ret = -EINVAL;
+		goto error_clk_put;
+	}
+
+	ret = v4l2_fwnode_endpoint_parse(endpoint, &priv->ep);
+	fwnode_handle_put(endpoint);
+	if (ret) {
+		dev_err(&client->dev, "Could not parse endpoint\n");
+		goto error_clk_put;
+	}
+
+	/* fallback to parallel mode */
+	if (priv->ep.bus_type != V4L2_MBUS_PARALLEL &&
+	    priv->ep.bus_type != V4L2_MBUS_BT656)
+		priv->ep.bus_type = V4L2_MBUS_PARALLEL;
+
 	ret = ov772x_video_probe(priv);
 	if (ret < 0)
 		goto error_gpio_put;