[PATCH v6 0/3] media: i2c: ov772x: Enable BT.656 mode and test pattern support

[PATCH v6 0/3] media: i2c: ov772x: Enable BT.656 mode and test pattern support

[Lad Prabhakar]

Hi All,

This patch series adds support for BT.656 mode in the ov772x sensor
and also enables color bar test pattern control.

Cheers,
Prabhakar

v5->v6
* Introduced new function ov772x_parse_dt()
* Moved the backward compatibility comment from 1/3 to 2/3

v4->v5:
* Put the ep instance back using fwnode_handle_put()
* Renamed BT656 to BT.656
* Correctly handled backward compatibility case falling
  back to parallel mode.

v3->v4:
* New patch 1/3 to fallback in parallel mode.
* Switched to v4l2_fwnode_endpoint_alloc_parse() for parsing the ep.
* Dropped support for pdat for test pattern control.
* DT documentation patches [1].

v2->v3:
* Dropped DT binding documentation patch as this is handled by Jacopo.
* Fixed review comments pointed by Jacopo.

v2:
 https://patchwork.kernel.org/project/linux-renesas-soc/
 list/?series=328133

 v1:
https://patchwork.kernel.org/project/linux-renesas-soc/
list/?series=323807

[1] https://patchwork.kernel.org/project/
    linux-renesas-soc/list/?series=346809

Lad Prabhakar (3):
  media: i2c: ov772x: Parse endpoint properties
  media: i2c: ov772x: Add support for BT.656 mode
  media: i2c: ov772x: Add test pattern control

 drivers/media/i2c/ov772x.c | 70 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 69 insertions(+), 1 deletion(-)

-- 
2.17.1

[PATCH v6 1/3] media: i2c: ov772x: Parse endpoint properties

[Lad Prabhakar]

Parse endpoint properties using v4l2_fwnode_endpoint_alloc_parse()
to determine the bus type and store it in the driver structure.

Set bus_type to V4L2_MBUS_PARALLEL as it's the only supported one

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
 drivers/media/i2c/ov772x.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
index 2cc6a678069a..f61a3f09ad64 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
+	enum v4l2_mbus_type		  bus_type;
 };
 
 /*
@@ -1348,6 +1350,34 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
 	.pad	= &ov772x_subdev_pad_ops,
 };
 
+static int ov772x_parse_dt(struct i2c_client *client,
+			   struct ov772x_priv *priv)
+{
+	struct v4l2_fwnode_endpoint bus_cfg;
+	struct fwnode_handle *ep;
+	int ret;
+
+	ep = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
+					    NULL);
+	if (!ep) {
+		dev_err(&client->dev, "Endpoint node not found\n");
+		return -EINVAL;
+	}
+
+	bus_cfg.bus_type = V4L2_MBUS_PARALLEL;
+	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
+	if (ret)
+		goto error_fwnode_put;
+
+	priv->bus_type = bus_cfg.bus_type;
+	v4l2_fwnode_endpoint_free(&bus_cfg);
+
+error_fwnode_put:
+	fwnode_handle_put(ep);
+
+	return ret;
+}
+
 /*
  * i2c_driver function
  */
@@ -1415,6 +1445,10 @@ static int ov772x_probe(struct i2c_client *client)
 		goto error_clk_put;
 	}
 
+	ret = ov772x_parse_dt(client, priv);
+	if (ret)
+		goto error_clk_put;
+
 	ret = ov772x_video_probe(priv);
 	if (ret < 0)
 		goto error_gpio_put;
-- 
2.17.1

[PATCH v6 2/3] media: i2c: ov772x: Add support for BT.656 mode

[Lad Prabhakar]

Add support to read the bus-type for V4L2_MBUS_BT656 and enable BT.656
mode in the sensor if needed.

For backward compatibility with older DTS where the bus-type property was
not mandatory, assume V4L2_MBUS_PARALLEL as it was the only supported bus
at the time. v4l2_fwnode_endpoint_alloc_parse() will not fail if
'bus-type' is not specified.

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 | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
index f61a3f09ad64..fe48b5881ad9 100644
--- a/drivers/media/i2c/ov772x.c
+++ b/drivers/media/i2c/ov772x.c
@@ -583,6 +583,13 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
 	if (priv->streaming == enable)
 		goto done;
 
+	if (priv->bus_type == V4L2_MBUS_BT656) {
+		ret = regmap_update_bits(priv->regmap, COM7, ITU656_ON_OFF,
+					 enable ? ITU656_ON_OFF : ~ITU656_ON_OFF);
+		if (ret)
+			goto done;
+	}
+
 	ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
 				 enable ? 0 : SOFT_SLEEP_MODE);
 	if (ret)
@@ -1364,10 +1371,22 @@ static int ov772x_parse_dt(struct i2c_client *client,
 		return -EINVAL;
 	}
 
+	/*
+	 * For backward compatibility with older DTS where the
+	 * bus-type property was not mandatory, assume
+	 * V4L2_MBUS_PARALLEL as it was the only supported bus at the
+	 * time. v4l2_fwnode_endpoint_alloc_parse() will not fail if
+	 * 'bus-type' is not specified.
+	 */
 	bus_cfg.bus_type = V4L2_MBUS_PARALLEL;
 	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
-	if (ret)
-		goto error_fwnode_put;
+	if (ret) {
+		bus_cfg = (struct v4l2_fwnode_endpoint)
+			  { .bus_type = V4L2_MBUS_BT656 };
+		ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
+		if (ret)
+			goto error_fwnode_put;
+	}
 
 	priv->bus_type = bus_cfg.bus_type;
 	v4l2_fwnode_endpoint_free(&bus_cfg);
-- 
2.17.1

[PATCH v6 3/3] media: i2c: ov772x: Add test pattern control

[Lad Prabhakar]

Add support for test pattern control supported by the sensor.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
---
 drivers/media/i2c/ov772x.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
index fe48b5881ad9..c3d36e003cad 100644
--- a/drivers/media/i2c/ov772x.c
+++ b/drivers/media/i2c/ov772x.c
@@ -227,7 +227,7 @@
 
 /* COM3 */
 #define SWAP_MASK       (SWAP_RGB | SWAP_YUV | SWAP_ML)
-#define IMG_MASK        (VFLIP_IMG | HFLIP_IMG)
+#define IMG_MASK        (VFLIP_IMG | HFLIP_IMG | SCOLOR_TEST)
 
 #define VFLIP_IMG       0x80	/* Vertical flip image ON/OFF selection */
 #define HFLIP_IMG       0x40	/* Horizontal mirror image ON/OFF selection */
@@ -425,6 +425,7 @@ struct ov772x_priv {
 	const struct ov772x_win_size     *win;
 	struct v4l2_ctrl		 *vflip_ctrl;
 	struct v4l2_ctrl		 *hflip_ctrl;
+	unsigned int			  test_pattern;
 	/* band_filter = COM8[5] ? 256 - BDBASE : 0 */
 	struct v4l2_ctrl		 *band_filter_ctrl;
 	unsigned int			  fps;
@@ -540,6 +541,11 @@ static const struct ov772x_win_size ov772x_win_sizes[] = {
 	},
 };
 
+static const char * const ov772x_test_pattern_menu[] = {
+	"Disabled",
+	"Vertical Color Bar Type 1",
+};
+
 /*
  * frame rate settings lists
  */
@@ -809,6 +815,9 @@ static int ov772x_s_ctrl(struct v4l2_ctrl *ctrl)
 		}
 
 		return ret;
+	case V4L2_CID_TEST_PATTERN:
+		priv->test_pattern = ctrl->val;
+		return 0;
 	}
 
 	return -EINVAL;
@@ -1107,6 +1116,8 @@ static int ov772x_set_params(struct ov772x_priv *priv,
 		val ^= VFLIP_IMG;
 	if (priv->hflip_ctrl->val)
 		val ^= HFLIP_IMG;
+	if (priv->test_pattern)
+		val |= SCOLOR_TEST;
 
 	ret = regmap_update_bits(priv->regmap, COM3, SWAP_MASK | IMG_MASK, val);
 	if (ret < 0)
@@ -1443,6 +1454,10 @@ static int ov772x_probe(struct i2c_client *client)
 	priv->band_filter_ctrl = v4l2_ctrl_new_std(&priv->hdl, &ov772x_ctrl_ops,
 						   V4L2_CID_BAND_STOP_FILTER,
 						   0, 256, 1, 0);
+	v4l2_ctrl_new_std_menu_items(&priv->hdl, &ov772x_ctrl_ops,
+				     V4L2_CID_TEST_PATTERN,
+				     ARRAY_SIZE(ov772x_test_pattern_menu) - 1,
+				     0, 0, ov772x_test_pattern_menu);
 	priv->subdev.ctrl_handler = &priv->hdl;
 	if (priv->hdl.error) {
 		ret = priv->hdl.error;
-- 
2.17.1

Re: [PATCH v6 1/3] media: i2c: ov772x: Parse endpoint properties

[Jacopo Mondi]

Hi

On Thu, Sep 17, 2020 at 06:42:22PM +0100, Lad Prabhakar wrote:
> Parse endpoint properties using v4l2_fwnode_endpoint_alloc_parse()
> to determine the bus type and store it in the driver structure.
>
> Set bus_type to V4L2_MBUS_PARALLEL as it's the only supported one
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Looks good!

Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>

Thanks
   j

> ---
>  drivers/media/i2c/ov772x.c | 34 ++++++++++++++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
>
> diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> index 2cc6a678069a..f61a3f09ad64 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
> +	enum v4l2_mbus_type		  bus_type;
>  };
>
>  /*
> @@ -1348,6 +1350,34 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
>  	.pad	= &ov772x_subdev_pad_ops,
>  };
>
> +static int ov772x_parse_dt(struct i2c_client *client,
> +			   struct ov772x_priv *priv)
> +{
> +	struct v4l2_fwnode_endpoint bus_cfg;
> +	struct fwnode_handle *ep;
> +	int ret;
> +
> +	ep = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
> +					    NULL);
> +	if (!ep) {
> +		dev_err(&client->dev, "Endpoint node not found\n");
> +		return -EINVAL;
> +	}
> +
> +	bus_cfg.bus_type = V4L2_MBUS_PARALLEL;
> +	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
> +	if (ret)
> +		goto error_fwnode_put;
> +
> +	priv->bus_type = bus_cfg.bus_type;
> +	v4l2_fwnode_endpoint_free(&bus_cfg);
> +
> +error_fwnode_put:
> +	fwnode_handle_put(ep);
> +
> +	return ret;
> +}
> +
>  /*
>   * i2c_driver function
>   */
> @@ -1415,6 +1445,10 @@ static int ov772x_probe(struct i2c_client *client)
>  		goto error_clk_put;
>  	}
>
> +	ret = ov772x_parse_dt(client, priv);
> +	if (ret)
> +		goto error_clk_put;
> +
>  	ret = ov772x_video_probe(priv);
>  	if (ret < 0)
>  		goto error_gpio_put;
> --
> 2.17.1
>

Re: [PATCH v6 2/3] media: i2c: ov772x: Add support for BT.656 mode

[Jacopo Mondi]

Hello,

On Thu, Sep 17, 2020 at 06:42:23PM +0100, Lad Prabhakar wrote:
> Add support to read the bus-type for V4L2_MBUS_BT656 and enable BT.656
> mode in the sensor if needed.
>
> For backward compatibility with older DTS where the bus-type property was
> not mandatory, assume V4L2_MBUS_PARALLEL as it was the only supported bus
> at the time. v4l2_fwnode_endpoint_alloc_parse() will not fail if
> 'bus-type' is not specified.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>

Thanks
  j

> ---
>  drivers/media/i2c/ov772x.c | 23 +++++++++++++++++++++--
>  1 file changed, 21 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> index f61a3f09ad64..fe48b5881ad9 100644
> --- a/drivers/media/i2c/ov772x.c
> +++ b/drivers/media/i2c/ov772x.c
> @@ -583,6 +583,13 @@ static int ov772x_s_stream(struct v4l2_subdev *sd, int enable)
>  	if (priv->streaming == enable)
>  		goto done;
>
> +	if (priv->bus_type == V4L2_MBUS_BT656) {
> +		ret = regmap_update_bits(priv->regmap, COM7, ITU656_ON_OFF,
> +					 enable ? ITU656_ON_OFF : ~ITU656_ON_OFF);
> +		if (ret)
> +			goto done;
> +	}
> +
>  	ret = regmap_update_bits(priv->regmap, COM2, SOFT_SLEEP_MODE,
>  				 enable ? 0 : SOFT_SLEEP_MODE);
>  	if (ret)
> @@ -1364,10 +1371,22 @@ static int ov772x_parse_dt(struct i2c_client *client,
>  		return -EINVAL;
>  	}
>
> +	/*
> +	 * For backward compatibility with older DTS where the
> +	 * bus-type property was not mandatory, assume
> +	 * V4L2_MBUS_PARALLEL as it was the only supported bus at the
> +	 * time. v4l2_fwnode_endpoint_alloc_parse() will not fail if
> +	 * 'bus-type' is not specified.
> +	 */
>  	bus_cfg.bus_type = V4L2_MBUS_PARALLEL;
>  	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
> -	if (ret)
> -		goto error_fwnode_put;
> +	if (ret) {
> +		bus_cfg = (struct v4l2_fwnode_endpoint)
> +			  { .bus_type = V4L2_MBUS_BT656 };
> +		ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
> +		if (ret)
> +			goto error_fwnode_put;
> +	}
>
>  	priv->bus_type = bus_cfg.bus_type;
>  	v4l2_fwnode_endpoint_free(&bus_cfg);
> --
> 2.17.1
>

Re: [PATCH v6 1/3] media: i2c: ov772x: Parse endpoint properties

[Sakari Ailus]

Hi Prabhakar,

On Thu, Sep 17, 2020 at 06:42:22PM +0100, Lad Prabhakar wrote:
> Parse endpoint properties using v4l2_fwnode_endpoint_alloc_parse()
> to determine the bus type and store it in the driver structure.
> 
> Set bus_type to V4L2_MBUS_PARALLEL as it's the only supported one
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>  drivers/media/i2c/ov772x.c | 34 ++++++++++++++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
> 
> diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> index 2cc6a678069a..f61a3f09ad64 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
> +	enum v4l2_mbus_type		  bus_type;
>  };
>  
>  /*
> @@ -1348,6 +1350,34 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
>  	.pad	= &ov772x_subdev_pad_ops,
>  };
>  
> +static int ov772x_parse_dt(struct i2c_client *client,
> +			   struct ov772x_priv *priv)
> +{
> +	struct v4l2_fwnode_endpoint bus_cfg;
> +	struct fwnode_handle *ep;
> +	int ret;
> +
> +	ep = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
> +					    NULL);
> +	if (!ep) {
> +		dev_err(&client->dev, "Endpoint node not found\n");
> +		return -EINVAL;
> +	}
> +
> +	bus_cfg.bus_type = V4L2_MBUS_PARALLEL;

Please zero the entire struct, i.e. do this assignment in the declaration.

You can also use v4l2_fwnode_endpoint_parse() if you're not using the link
frequencies --- sensor drivers generally should but you could only add them
as optional at this point (out of scope of this patch).

> +	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
> +	if (ret)
> +		goto error_fwnode_put;
> +
> +	priv->bus_type = bus_cfg.bus_type;
> +	v4l2_fwnode_endpoint_free(&bus_cfg);
> +
> +error_fwnode_put:
> +	fwnode_handle_put(ep);
> +
> +	return ret;
> +}
> +
>  /*
>   * i2c_driver function
>   */
> @@ -1415,6 +1445,10 @@ static int ov772x_probe(struct i2c_client *client)
>  		goto error_clk_put;
>  	}
>  
> +	ret = ov772x_parse_dt(client, priv);
> +	if (ret)
> +		goto error_clk_put;
> +
>  	ret = ov772x_video_probe(priv);
>  	if (ret < 0)
>  		goto error_gpio_put;
> -- 
> 2.17.1
> 

-- 
Sakari Ailus

Re: [PATCH v6 1/3] media: i2c: ov772x: Parse endpoint properties

[Lad, Prabhakar]

HI Sakari,

Thank you for the review.

On Wed, Sep 30, 2020 at 12:45 PM Sakari Ailus
<sakari.ailus@linux.intel.com> wrote:
>
> Hi Prabhakar,
>
> On Thu, Sep 17, 2020 at 06:42:22PM +0100, Lad Prabhakar wrote:
> > Parse endpoint properties using v4l2_fwnode_endpoint_alloc_parse()
> > to determine the bus type and store it in the driver structure.
> >
> > Set bus_type to V4L2_MBUS_PARALLEL as it's the only supported one
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > ---
> >  drivers/media/i2c/ov772x.c | 34 ++++++++++++++++++++++++++++++++++
> >  1 file changed, 34 insertions(+)
> >
> > diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> > index 2cc6a678069a..f61a3f09ad64 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
> > +     enum v4l2_mbus_type               bus_type;
> >  };
> >
> >  /*
> > @@ -1348,6 +1350,34 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
> >       .pad    = &ov772x_subdev_pad_ops,
> >  };
> >
> > +static int ov772x_parse_dt(struct i2c_client *client,
> > +                        struct ov772x_priv *priv)
> > +{
> > +     struct v4l2_fwnode_endpoint bus_cfg;
> > +     struct fwnode_handle *ep;
> > +     int ret;
> > +
> > +     ep = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
> > +                                         NULL);
> > +     if (!ep) {
> > +             dev_err(&client->dev, "Endpoint node not found\n");
> > +             return -EINVAL;
> > +     }
> > +
> > +     bus_cfg.bus_type = V4L2_MBUS_PARALLEL;
>
> Please zero the entire struct, i.e. do this assignment in the declaration.
>
Agreed, but instead at the declaration I would prefer here as below,
since patch 2/3 has a comment related to backward compatibility with
the bindings. Is this OK with you ?
    bus_cfg = (struct v4l2_fwnode_endpoint)
          { .bus_type = V4L2_MBUS_PARALLEL };

> You can also use v4l2_fwnode_endpoint_parse() if you're not using the link
> frequencies --- sensor drivers generally should but you could only add them
> as optional at this point (out of scope of this patch).
>
will stick with this for now :)

Cheers,
Prabhakar

Re: [PATCH v6 1/3] media: i2c: ov772x: Parse endpoint properties

[Sakari Ailus]

On Wed, Sep 30, 2020 at 01:19:40PM +0100, Lad, Prabhakar wrote:
> HI Sakari,
> 
> Thank you for the review.
> 
> On Wed, Sep 30, 2020 at 12:45 PM Sakari Ailus
> <sakari.ailus@linux.intel.com> wrote:
> >
> > Hi Prabhakar,
> >
> > On Thu, Sep 17, 2020 at 06:42:22PM +0100, Lad Prabhakar wrote:
> > > Parse endpoint properties using v4l2_fwnode_endpoint_alloc_parse()
> > > to determine the bus type and store it in the driver structure.
> > >
> > > Set bus_type to V4L2_MBUS_PARALLEL as it's the only supported one
> > >
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > ---
> > >  drivers/media/i2c/ov772x.c | 34 ++++++++++++++++++++++++++++++++++
> > >  1 file changed, 34 insertions(+)
> > >
> > > diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> > > index 2cc6a678069a..f61a3f09ad64 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
> > > +     enum v4l2_mbus_type               bus_type;
> > >  };
> > >
> > >  /*
> > > @@ -1348,6 +1350,34 @@ static const struct v4l2_subdev_ops ov772x_subdev_ops = {
> > >       .pad    = &ov772x_subdev_pad_ops,
> > >  };
> > >
> > > +static int ov772x_parse_dt(struct i2c_client *client,
> > > +                        struct ov772x_priv *priv)
> > > +{
> > > +     struct v4l2_fwnode_endpoint bus_cfg;
> > > +     struct fwnode_handle *ep;
> > > +     int ret;
> > > +
> > > +     ep = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev),
> > > +                                         NULL);
> > > +     if (!ep) {
> > > +             dev_err(&client->dev, "Endpoint node not found\n");
> > > +             return -EINVAL;
> > > +     }
> > > +
> > > +     bus_cfg.bus_type = V4L2_MBUS_PARALLEL;
> >
> > Please zero the entire struct, i.e. do this assignment in the declaration.
> >
> Agreed, but instead at the declaration I would prefer here as below,
> since patch 2/3 has a comment related to backward compatibility with
> the bindings. Is this OK with you ?
>     bus_cfg = (struct v4l2_fwnode_endpoint)
>           { .bus_type = V4L2_MBUS_PARALLEL };

Why not in variable declaration?

-- 
Sakari Ailus