[PATCH v2] media: i2c: imx219: Implement get_selection

[PATCH v2] media: i2c: imx219: Implement get_selection

[Jacopo Mondi]

Implement the get_selection pad operation for the IMX219 sensor driver.
The supported targets report the sensor's native size, the crop default
rectangle and the crop rectangle.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>

---
v1->v2:
- Add crop rectangle for 640x480 mode that was missing in v1
- Rework get selection function as suggested by Laurent
- Add Laurent's tag
---
 drivers/media/i2c/imx219.c | 97 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)

diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
index cb03bdec1f9c..2744669fb419 100644
--- a/drivers/media/i2c/imx219.c
+++ b/drivers/media/i2c/imx219.c
@@ -112,6 +112,14 @@
 #define IMX219_TESTP_BLUE_DEFAULT	0
 #define IMX219_TESTP_GREENB_DEFAULT	0

+/* IMX219 native and active pixel array size. */
+#define IMX219_NATIVE_WIDTH		3296U
+#define IMX219_NATIVE_HEIGHT		2480U
+#define IMX219_PIXEL_ARRAY_LEFT		8U
+#define IMX219_PIXEL_ARRAY_TOP		8U
+#define IMX219_PIXEL_ARRAY_WIDTH	3280U
+#define IMX219_PIXEL_ARRAY_HEIGHT	2464U
+
 struct imx219_reg {
 	u16 address;
 	u8 val;
@@ -129,6 +137,9 @@ struct imx219_mode {
 	/* Frame height */
 	unsigned int height;

+	/* Analog crop rectangle. */
+	struct v4l2_rect crop;
+
 	/* V-timing */
 	unsigned int vts_def;

@@ -463,6 +474,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 8MPix 15fps mode */
 		.width = 3280,
 		.height = 2464,
+		.crop = {
+			.top = 0,
+			.left = 0,
+			.width = 3280,
+			.height = 2464
+		},
 		.vts_def = IMX219_VTS_15FPS,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_3280x2464_regs),
@@ -473,6 +490,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 1080P 30fps cropped */
 		.width = 1920,
 		.height = 1080,
+		.crop = {
+			.top = 692,
+			.left = 680,
+			.width = 1920,
+			.height = 1080
+		},
 		.vts_def = IMX219_VTS_30FPS_1080P,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_1920_1080_regs),
@@ -483,6 +506,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 2x2 binned 30fps mode */
 		.width = 1640,
 		.height = 1232,
+		.crop = {
+			.top = 0,
+			.left = 0,
+			.width = 3280,
+			.height = 2464
+		},
 		.vts_def = IMX219_VTS_30FPS_BINNED,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_1640_1232_regs),
@@ -654,6 +683,7 @@ static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 	struct imx219 *imx219 = to_imx219(sd);
 	struct v4l2_mbus_framefmt *try_fmt =
 		v4l2_subdev_get_try_format(sd, fh->pad, 0);
+	struct v4l2_rect *try_crop;

 	mutex_lock(&imx219->mutex);

@@ -664,6 +694,13 @@ static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 					       MEDIA_BUS_FMT_SRGGB10_1X10);
 	try_fmt->field = V4L2_FIELD_NONE;

+	/* Initialize try_crop rectangle. */
+	try_crop = v4l2_subdev_get_try_crop(sd, fh->pad, 0);
+	try_crop->top = IMX219_PIXEL_ARRAY_TOP;
+	try_crop->left = IMX219_PIXEL_ARRAY_LEFT;
+	try_crop->width = IMX219_PIXEL_ARRAY_WIDTH;
+	try_crop->height = IMX219_PIXEL_ARRAY_HEIGHT;
+
 	mutex_unlock(&imx219->mutex);

 	return 0;
@@ -928,6 +965,65 @@ static int imx219_set_framefmt(struct imx219 *imx219)
 	return -EINVAL;
 }

+static const struct v4l2_rect *
+__imx219_get_pad_crop(struct imx219 *imx219, struct v4l2_subdev_pad_config *cfg,
+		      unsigned int pad, enum v4l2_subdev_format_whence which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_crop(&imx219->sd, cfg, pad);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &imx219->mode->crop;
+	default:
+		return NULL;
+	}
+}
+
+static int imx219_get_selection(struct v4l2_subdev *sd,
+				struct v4l2_subdev_pad_config *cfg,
+				struct v4l2_subdev_selection *sel)
+{
+	struct imx219 *imx219 = to_imx219(sd);
+	const struct v4l2_rect *__crop;
+
+	if (sel->pad != 0)
+		return -EINVAL;
+
+	mutex_lock(&imx219->mutex);
+
+	switch (sel->target) {
+	case V4L2_SEL_TGT_NATIVE_SIZE:
+		sel->r.top = 0;
+		sel->r.left = 0;
+		sel->r.width = IMX219_NATIVE_WIDTH;
+		sel->r.height = IMX219_NATIVE_HEIGHT;
+		mutex_unlock(&imx219->mutex);
+
+		return 0;
+
+	case V4L2_SEL_TGT_CROP_DEFAULT:
+		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
+		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
+		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
+		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
+		mutex_unlock(&imx219->mutex);
+
+		return 0;
+
+	case V4L2_SEL_TGT_CROP:
+		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
+					       sel->which);
+		sel->r = *__crop;
+		mutex_unlock(&imx219->mutex);
+
+		return 0;
+	}
+
+	mutex_unlock(&imx219->mutex);
+
+	return -EINVAL;
+}
+
 static int imx219_start_streaming(struct imx219 *imx219)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
@@ -1152,6 +1248,7 @@ static const struct v4l2_subdev_pad_ops imx219_pad_ops = {
 	.enum_mbus_code = imx219_enum_mbus_code,
 	.get_fmt = imx219_get_pad_format,
 	.set_fmt = imx219_set_pad_format,
+	.get_selection = imx219_get_selection,
 	.enum_frame_size = imx219_enum_frame_size,
 };

--
2.26.1

Re: [PATCH v2] media: i2c: imx219: Implement get_selection

[Laurent Pinchart]

Hi Jacopo,

Thank you for the patch.

On Sun, Apr 26, 2020 at 10:52:50PM +0200, Jacopo Mondi wrote:
> Implement the get_selection pad operation for the IMX219 sensor driver.
> The supported targets report the sensor's native size, the crop default
> rectangle and the crop rectangle.
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
> 
> ---
> v1->v2:
> - Add crop rectangle for 640x480 mode that was missing in v1
> - Rework get selection function as suggested by Laurent
> - Add Laurent's tag
> ---
>  drivers/media/i2c/imx219.c | 97 ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 97 insertions(+)
> 
> diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> index cb03bdec1f9c..2744669fb419 100644
> --- a/drivers/media/i2c/imx219.c
> +++ b/drivers/media/i2c/imx219.c
> @@ -112,6 +112,14 @@
>  #define IMX219_TESTP_BLUE_DEFAULT	0
>  #define IMX219_TESTP_GREENB_DEFAULT	0
> 
> +/* IMX219 native and active pixel array size. */
> +#define IMX219_NATIVE_WIDTH		3296U
> +#define IMX219_NATIVE_HEIGHT		2480U
> +#define IMX219_PIXEL_ARRAY_LEFT		8U
> +#define IMX219_PIXEL_ARRAY_TOP		8U
> +#define IMX219_PIXEL_ARRAY_WIDTH	3280U
> +#define IMX219_PIXEL_ARRAY_HEIGHT	2464U
> +
>  struct imx219_reg {
>  	u16 address;
>  	u8 val;
> @@ -129,6 +137,9 @@ struct imx219_mode {
>  	/* Frame height */
>  	unsigned int height;
> 
> +	/* Analog crop rectangle. */
> +	struct v4l2_rect crop;
> +
>  	/* V-timing */
>  	unsigned int vts_def;
> 
> @@ -463,6 +474,12 @@ static const struct imx219_mode supported_modes[] = {
>  		/* 8MPix 15fps mode */
>  		.width = 3280,
>  		.height = 2464,
> +		.crop = {
> +			.top = 0,
> +			.left = 0,
> +			.width = 3280,
> +			.height = 2464
> +		},
>  		.vts_def = IMX219_VTS_15FPS,
>  		.reg_list = {
>  			.num_of_regs = ARRAY_SIZE(mode_3280x2464_regs),
> @@ -473,6 +490,12 @@ static const struct imx219_mode supported_modes[] = {
>  		/* 1080P 30fps cropped */
>  		.width = 1920,
>  		.height = 1080,
> +		.crop = {
> +			.top = 692,
> +			.left = 680,
> +			.width = 1920,
> +			.height = 1080
> +		},
>  		.vts_def = IMX219_VTS_30FPS_1080P,
>  		.reg_list = {
>  			.num_of_regs = ARRAY_SIZE(mode_1920_1080_regs),
> @@ -483,6 +506,12 @@ static const struct imx219_mode supported_modes[] = {
>  		/* 2x2 binned 30fps mode */
>  		.width = 1640,
>  		.height = 1232,
> +		.crop = {
> +			.top = 0,
> +			.left = 0,
> +			.width = 3280,
> +			.height = 2464
> +		},
>  		.vts_def = IMX219_VTS_30FPS_BINNED,
>  		.reg_list = {
>  			.num_of_regs = ARRAY_SIZE(mode_1640_1232_regs),
> @@ -654,6 +683,7 @@ static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
>  	struct imx219 *imx219 = to_imx219(sd);
>  	struct v4l2_mbus_framefmt *try_fmt =
>  		v4l2_subdev_get_try_format(sd, fh->pad, 0);
> +	struct v4l2_rect *try_crop;
> 
>  	mutex_lock(&imx219->mutex);
> 
> @@ -664,6 +694,13 @@ static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
>  					       MEDIA_BUS_FMT_SRGGB10_1X10);
>  	try_fmt->field = V4L2_FIELD_NONE;
> 
> +	/* Initialize try_crop rectangle. */
> +	try_crop = v4l2_subdev_get_try_crop(sd, fh->pad, 0);
> +	try_crop->top = IMX219_PIXEL_ARRAY_TOP;
> +	try_crop->left = IMX219_PIXEL_ARRAY_LEFT;
> +	try_crop->width = IMX219_PIXEL_ARRAY_WIDTH;
> +	try_crop->height = IMX219_PIXEL_ARRAY_HEIGHT;
> +
>  	mutex_unlock(&imx219->mutex);
> 
>  	return 0;
> @@ -928,6 +965,65 @@ static int imx219_set_framefmt(struct imx219 *imx219)
>  	return -EINVAL;
>  }
> 
> +static const struct v4l2_rect *
> +__imx219_get_pad_crop(struct imx219 *imx219, struct v4l2_subdev_pad_config *cfg,
> +		      unsigned int pad, enum v4l2_subdev_format_whence which)
> +{
> +	switch (which) {
> +	case V4L2_SUBDEV_FORMAT_TRY:
> +		return v4l2_subdev_get_try_crop(&imx219->sd, cfg, pad);
> +	case V4L2_SUBDEV_FORMAT_ACTIVE:
> +		return &imx219->mode->crop;
> +	default:
> +		return NULL;
> +	}
> +}
> +
> +static int imx219_get_selection(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_pad_config *cfg,
> +				struct v4l2_subdev_selection *sel)
> +{
> +	struct imx219 *imx219 = to_imx219(sd);
> +	const struct v4l2_rect *__crop;
> +
> +	if (sel->pad != 0)
> +		return -EINVAL;
> +
> +	mutex_lock(&imx219->mutex);
> +
> +	switch (sel->target) {
> +	case V4L2_SEL_TGT_NATIVE_SIZE:
> +		sel->r.top = 0;
> +		sel->r.left = 0;
> +		sel->r.width = IMX219_NATIVE_WIDTH;
> +		sel->r.height = IMX219_NATIVE_HEIGHT;
> +		mutex_unlock(&imx219->mutex);
> +
> +		return 0;
> +
> +	case V4L2_SEL_TGT_CROP_DEFAULT:
> +		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> +		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> +		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> +		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> +		mutex_unlock(&imx219->mutex);
> +
> +		return 0;
> +
> +	case V4L2_SEL_TGT_CROP:
> +		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> +					       sel->which);
> +		sel->r = *__crop;
> +		mutex_unlock(&imx219->mutex);

I should have thought about it before, but only this case requires
locking. Maybe

		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
					       sel->which);
		mutex_lock(&imx219->mutex);
		sel->r = *__crop;
		mutex_unlock(&imx219->mutex);

and removing the mutex_lock() at the beginning ?

> +
> +		return 0;
> +	}
> +
> +	mutex_unlock(&imx219->mutex);
> +
> +	return -EINVAL;
> +}
> +
>  static int imx219_start_streaming(struct imx219 *imx219)
>  {
>  	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
> @@ -1152,6 +1248,7 @@ static const struct v4l2_subdev_pad_ops imx219_pad_ops = {
>  	.enum_mbus_code = imx219_enum_mbus_code,
>  	.get_fmt = imx219_get_pad_format,
>  	.set_fmt = imx219_set_pad_format,
> +	.get_selection = imx219_get_selection,
>  	.enum_frame_size = imx219_enum_frame_size,
>  };
> 
> --
> 2.26.1
> 

-- 
Regards,

Laurent Pinchart

[PATCH v2.1] media: i2c: imx219: Implement get_selection

[Jacopo Mondi]

Implement the get_selection pad operation for the IMX219 sensor driver.
The supported targets report the sensor's native size, the crop default
rectangle and the crop rectangle.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
---
v2->v2,1
- This is really v2, sorry for the mess

v1->v2:
- Add crop rectangle for 640x480 mode that was missing in v1
- Rework get selection function as suggested by Laurent
- Add Laurent's tag
---
 drivers/media/i2c/imx219.c | 102 +++++++++++++++++++++++++++++++++++++
 1 file changed, 102 insertions(+)

diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
index cb03bdec1f9c..f6fa211ce25e 100644
--- a/drivers/media/i2c/imx219.c
+++ b/drivers/media/i2c/imx219.c
@@ -112,6 +112,14 @@
 #define IMX219_TESTP_BLUE_DEFAULT	0
 #define IMX219_TESTP_GREENB_DEFAULT	0

+/* IMX219 native and active pixel array size. */
+#define IMX219_NATIVE_WIDTH		3296U
+#define IMX219_NATIVE_HEIGHT		2480U
+#define IMX219_PIXEL_ARRAY_LEFT		8U
+#define IMX219_PIXEL_ARRAY_TOP		8U
+#define IMX219_PIXEL_ARRAY_WIDTH	3280U
+#define IMX219_PIXEL_ARRAY_HEIGHT	2464U
+
 struct imx219_reg {
 	u16 address;
 	u8 val;
@@ -129,6 +137,9 @@ struct imx219_mode {
 	/* Frame height */
 	unsigned int height;

+	/* Analog crop rectangle. */
+	struct v4l2_rect crop;
+
 	/* V-timing */
 	unsigned int vts_def;

@@ -463,6 +474,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 8MPix 15fps mode */
 		.width = 3280,
 		.height = 2464,
+		.crop = {
+			.left = 0,
+			.top = 0,
+			.width = 3280,
+			.height = 2464
+		},
 		.vts_def = IMX219_VTS_15FPS,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_3280x2464_regs),
@@ -473,6 +490,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 1080P 30fps cropped */
 		.width = 1920,
 		.height = 1080,
+		.crop = {
+			.left = 680,
+			.top = 692,
+			.width = 1920,
+			.height = 1080
+		},
 		.vts_def = IMX219_VTS_30FPS_1080P,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_1920_1080_regs),
@@ -483,6 +506,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 2x2 binned 30fps mode */
 		.width = 1640,
 		.height = 1232,
+		.crop = {
+			.left = 0,
+			.top = 0,
+			.width = 3280,
+			.height = 2464
+		},
 		.vts_def = IMX219_VTS_30FPS_BINNED,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_1640_1232_regs),
@@ -493,6 +522,12 @@ static const struct imx219_mode supported_modes[] = {
 		/* 640x480 30fps mode */
 		.width = 640,
 		.height = 480,
+		.crop = {
+			.left = 1000,
+			.top = 752,
+			.width = 1280,
+			.height = 960
+		},
 		.vts_def = IMX219_VTS_30FPS_640x480,
 		.reg_list = {
 			.num_of_regs = ARRAY_SIZE(mode_640_480_regs),
@@ -654,6 +689,7 @@ static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 	struct imx219 *imx219 = to_imx219(sd);
 	struct v4l2_mbus_framefmt *try_fmt =
 		v4l2_subdev_get_try_format(sd, fh->pad, 0);
+	struct v4l2_rect *try_crop;

 	mutex_lock(&imx219->mutex);

@@ -664,6 +700,13 @@ static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 					       MEDIA_BUS_FMT_SRGGB10_1X10);
 	try_fmt->field = V4L2_FIELD_NONE;

+	/* Initialize try_crop rectangle. */
+	try_crop = v4l2_subdev_get_try_crop(sd, fh->pad, 0);
+	try_crop->top = IMX219_PIXEL_ARRAY_TOP;
+	try_crop->left = IMX219_PIXEL_ARRAY_LEFT;
+	try_crop->width = IMX219_PIXEL_ARRAY_WIDTH;
+	try_crop->height = IMX219_PIXEL_ARRAY_HEIGHT;
+
 	mutex_unlock(&imx219->mutex);

 	return 0;
@@ -928,6 +971,64 @@ static int imx219_set_framefmt(struct imx219 *imx219)
 	return -EINVAL;
 }

+static const struct v4l2_rect *
+__imx219_get_pad_crop(struct imx219 *imx219, struct v4l2_subdev_pad_config *cfg,
+		      unsigned int pad, enum v4l2_subdev_format_whence which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_crop(&imx219->sd, cfg, pad);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &imx219->mode->crop;
+	default:
+		return NULL;
+	}
+}
+
+static int imx219_get_selection(struct v4l2_subdev *sd,
+				struct v4l2_subdev_pad_config *cfg,
+				struct v4l2_subdev_selection *sel)
+{
+	struct imx219 *imx219 = to_imx219(sd);
+	const struct v4l2_rect *__crop;
+	int ret = 0;
+
+	if (sel->pad != 0)
+		return -EINVAL;
+
+	mutex_lock(&imx219->mutex);
+
+	switch (sel->target) {
+	case V4L2_SEL_TGT_NATIVE_SIZE:
+		sel->r.top = 0;
+		sel->r.left = 0;
+		sel->r.width = IMX219_NATIVE_WIDTH;
+		sel->r.height = IMX219_NATIVE_HEIGHT;
+		break;
+
+	case V4L2_SEL_TGT_CROP_DEFAULT:
+		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
+		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
+		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
+		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
+		break;
+
+	case V4L2_SEL_TGT_CROP:
+		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
+					       sel->which);
+		sel->r = *__crop;
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	mutex_unlock(&imx219->mutex);
+
+	return ret;
+}
+
 static int imx219_start_streaming(struct imx219 *imx219)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
@@ -1152,6 +1253,7 @@ static const struct v4l2_subdev_pad_ops imx219_pad_ops = {
 	.enum_mbus_code = imx219_enum_mbus_code,
 	.get_fmt = imx219_get_pad_format,
 	.set_fmt = imx219_set_pad_format,
+	.get_selection = imx219_get_selection,
 	.enum_frame_size = imx219_enum_frame_size,
 };

--
2.26.1

Re: [PATCH v2] media: i2c: imx219: Implement get_selection

[Jacopo Mondi]

Hi Laurent

On Mon, Apr 27, 2020 at 12:05:48AM +0300, Laurent Pinchart wrote:
> Hi Jacopo,
>
> Thank you for the patch.
>

[snip]

> > +
> > +static int imx219_get_selection(struct v4l2_subdev *sd,
> > +				struct v4l2_subdev_pad_config *cfg,
> > +				struct v4l2_subdev_selection *sel)
> > +{
> > +	struct imx219 *imx219 = to_imx219(sd);
> > +	const struct v4l2_rect *__crop;
> > +
> > +	if (sel->pad != 0)
> > +		return -EINVAL;
> > +
> > +	mutex_lock(&imx219->mutex);
> > +
> > +	switch (sel->target) {
> > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > +		sel->r.top = 0;
> > +		sel->r.left = 0;
> > +		sel->r.width = IMX219_NATIVE_WIDTH;
> > +		sel->r.height = IMX219_NATIVE_HEIGHT;
> > +		mutex_unlock(&imx219->mutex);
> > +
> > +		return 0;
> > +
> > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > +		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > +		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > +		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > +		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > +		mutex_unlock(&imx219->mutex);
> > +
> > +		return 0;
> > +
> > +	case V4L2_SEL_TGT_CROP:
> > +		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> > +					       sel->which);
> > +		sel->r = *__crop;
> > +		mutex_unlock(&imx219->mutex);
>
> I should have thought about it before, but only this case requires
> locking. Maybe

I should have thought it better, yes

>
> 		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> 					       sel->which);
> 		mutex_lock(&imx219->mutex);

Actually, retreiveing __crop should be protected too, as the crop
rectangle is part of the imx219->mode, which is updated by the set_fmt
operation.

I'll wrap the whole case content in a critical session.

Thanks
  j

> 		sel->r = *__crop;
> 		mutex_unlock(&imx219->mutex);
>
> and removing the mutex_lock() at the beginning ?
>
> > +
> > +		return 0;
> > +	}
> > +
> > +	mutex_unlock(&imx219->mutex);
> > +
> > +	return -EINVAL;
> > +}
> > +
> >  static int imx219_start_streaming(struct imx219 *imx219)
> >  {
> >  	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
> > @@ -1152,6 +1248,7 @@ static const struct v4l2_subdev_pad_ops imx219_pad_ops = {
> >  	.enum_mbus_code = imx219_enum_mbus_code,
> >  	.get_fmt = imx219_get_pad_format,
> >  	.set_fmt = imx219_set_pad_format,
> > +	.get_selection = imx219_get_selection,
> >  	.enum_frame_size = imx219_enum_frame_size,
> >  };
> >
> > --
> > 2.26.1
> >
>
> --
> Regards,
>
> Laurent Pinchart

Re: [PATCH v2] media: i2c: imx219: Implement get_selection

[Laurent Pinchart]

Hi Jacopo,

On Tue, Apr 28, 2020 at 03:40:36PM +0200, Jacopo Mondi wrote:
> On Mon, Apr 27, 2020 at 12:05:48AM +0300, Laurent Pinchart wrote:
> > Hi Jacopo,
> >
> > Thank you for the patch.
> >
> 
> [snip]
> 
> > > +
> > > +static int imx219_get_selection(struct v4l2_subdev *sd,
> > > +				struct v4l2_subdev_pad_config *cfg,
> > > +				struct v4l2_subdev_selection *sel)
> > > +{
> > > +	struct imx219 *imx219 = to_imx219(sd);
> > > +	const struct v4l2_rect *__crop;
> > > +
> > > +	if (sel->pad != 0)
> > > +		return -EINVAL;
> > > +
> > > +	mutex_lock(&imx219->mutex);
> > > +
> > > +	switch (sel->target) {
> > > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > +		sel->r.top = 0;
> > > +		sel->r.left = 0;
> > > +		sel->r.width = IMX219_NATIVE_WIDTH;
> > > +		sel->r.height = IMX219_NATIVE_HEIGHT;
> > > +		mutex_unlock(&imx219->mutex);
> > > +
> > > +		return 0;
> > > +
> > > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > +		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > +		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > +		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > +		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > +		mutex_unlock(&imx219->mutex);
> > > +
> > > +		return 0;
> > > +
> > > +	case V4L2_SEL_TGT_CROP:
> > > +		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> > > +					       sel->which);
> > > +		sel->r = *__crop;
> > > +		mutex_unlock(&imx219->mutex);
> >
> > I should have thought about it before, but only this case requires
> > locking. Maybe
> 
> I should have thought it better, yes
> 
> >
> > 		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> > 					       sel->which);
> > 		mutex_lock(&imx219->mutex);
> 
> Actually, retreiveing __crop should be protected too, as the crop
> rectangle is part of the imx219->mode, which is updated by the set_fmt
> operation.

__crop is a pointer, retrieving the pointer doesn't need protection.
Accessing its contents does. No big deal though, it's cheap, as long as
we don't lock for the bounds and default cases.

> I'll wrap the whole case content in a critical session.
> 
> > 		sel->r = *__crop;
> > 		mutex_unlock(&imx219->mutex);
> >
> > and removing the mutex_lock() at the beginning ?
> >
> > > +
> > > +		return 0;
> > > +	}
> > > +
> > > +	mutex_unlock(&imx219->mutex);
> > > +
> > > +	return -EINVAL;
> > > +}
> > > +
> > >  static int imx219_start_streaming(struct imx219 *imx219)
> > >  {
> > >  	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
> > > @@ -1152,6 +1248,7 @@ static const struct v4l2_subdev_pad_ops imx219_pad_ops = {
> > >  	.enum_mbus_code = imx219_enum_mbus_code,
> > >  	.get_fmt = imx219_get_pad_format,
> > >  	.set_fmt = imx219_set_pad_format,
> > > +	.get_selection = imx219_get_selection,
> > >  	.enum_frame_size = imx219_enum_frame_size,
> > >  };
> > >

-- 
Regards,

Laurent Pinchart

Re: [PATCH v2] media: i2c: imx219: Implement get_selection

[Jacopo Mondi]

Hi Laurent,

On Tue, Apr 28, 2020 at 04:41:53PM +0300, Laurent Pinchart wrote:
> Hi Jacopo,
>
> On Tue, Apr 28, 2020 at 03:40:36PM +0200, Jacopo Mondi wrote:
> > On Mon, Apr 27, 2020 at 12:05:48AM +0300, Laurent Pinchart wrote:
> > > Hi Jacopo,
> > >
> > > Thank you for the patch.
> > >
> >
> > [snip]
> >
> > > > +
> > > > +static int imx219_get_selection(struct v4l2_subdev *sd,
> > > > +				struct v4l2_subdev_pad_config *cfg,
> > > > +				struct v4l2_subdev_selection *sel)
> > > > +{
> > > > +	struct imx219 *imx219 = to_imx219(sd);
> > > > +	const struct v4l2_rect *__crop;
> > > > +
> > > > +	if (sel->pad != 0)
> > > > +		return -EINVAL;
> > > > +
> > > > +	mutex_lock(&imx219->mutex);
> > > > +
> > > > +	switch (sel->target) {
> > > > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > +		sel->r.top = 0;
> > > > +		sel->r.left = 0;
> > > > +		sel->r.width = IMX219_NATIVE_WIDTH;
> > > > +		sel->r.height = IMX219_NATIVE_HEIGHT;
> > > > +		mutex_unlock(&imx219->mutex);
> > > > +
> > > > +		return 0;
> > > > +
> > > > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > > +		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > > +		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > > +		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > > +		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > > +		mutex_unlock(&imx219->mutex);
> > > > +
> > > > +		return 0;
> > > > +
> > > > +	case V4L2_SEL_TGT_CROP:
> > > > +		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> > > > +					       sel->which);
> > > > +		sel->r = *__crop;
> > > > +		mutex_unlock(&imx219->mutex);
> > >
> > > I should have thought about it before, but only this case requires
> > > locking. Maybe
> >
> > I should have thought it better, yes
> >
> > >
> > > 		__crop = __imx219_get_pad_crop(imx219, cfg, sel->pad,
> > > 					       sel->which);
> > > 		mutex_lock(&imx219->mutex);
> >
> > Actually, retreiveing __crop should be protected too, as the crop
> > rectangle is part of the imx219->mode, which is updated by the set_fmt
> > operation.
>
> __crop is a pointer, retrieving the pointer doesn't need protection.
> Accessing its contents does. No big deal though, it's cheap, as long as
> we don't lock for the bounds and default cases.

Sorry, I was not clear maybe.

- __crop points to imx219->mode->crop
- set_fmt updates imx219->mode
- in the tiny window between when we get a pointer to
  imx219->mode->crop and we enter the critical section here a set_fmt call
  can update the imx219->mode, so we'll have here a pointer to the
  previous crop rectangle.

Unlikely, but yet, possible.