Re: [PATCH v3 04/33] v4l: VIDIOC_SUBDEV_S_SELECTION and VIDIOC_SUBDEV_G_SELECTION IOCTLs

[Sakari Ailus <sakari.ailus@iki.fi>]

Hi Laurent,

Laurent Pinchart wrote:
> Hi Sakari,
> 
> Thanks for the patch.

And thank you for the review!!!

> On Monday 20 February 2012 03:56:43 Sakari Ailus wrote:
>> Add support for VIDIOC_SUBDEV_S_SELECTION and VIDIOC_SUBDEV_G_SELECTION
>> IOCTLs. They replace functionality provided by VIDIOC_SUBDEV_S_CROP and
>> VIDIOC_SUBDEV_G_CROP IOCTLs and also add new functionality (composing).
>>
>> VIDIOC_SUBDEV_G_CROP and VIDIOC_SUBDEV_S_CROP continue to be supported.
>>
>> Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
>> ---
>>  drivers/media/video/v4l2-subdev.c |   34 +++++++++++++++++++++---------
>>  include/linux/v4l2-subdev.h       |   41
>> +++++++++++++++++++++++++++++++++++++ include/media/v4l2-subdev.h       |  
>> 21 +++++++++++++++---
>>  3 files changed, 82 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/media/video/v4l2-subdev.c
>> b/drivers/media/video/v4l2-subdev.c index 6fe88e9..30c7fd9 100644
>> --- a/drivers/media/video/v4l2-subdev.c
>> +++ b/drivers/media/video/v4l2-subdev.c
>> @@ -35,14 +35,9 @@
>>  static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev
>> *sd) {
>>  #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
>> -	/* Allocate try format and crop in the same memory block */
>> -	fh->try_fmt = kzalloc((sizeof(*fh->try_fmt) + sizeof(*fh->try_crop))
>> -			      * sd->entity.num_pads, GFP_KERNEL);
>> -	if (fh->try_fmt == NULL)
>> +	fh->pad = kzalloc(sizeof(*fh->pad) * sd->entity.num_pads, GFP_KERNEL);
>> +	if (fh->pad == NULL)
>>  		return -ENOMEM;
>> -
>> -	fh->try_crop = (struct v4l2_rect *)
>> -		(fh->try_fmt + sd->entity.num_pads);
>>  #endif
>>  	return 0;
>>  }
>> @@ -50,9 +45,8 @@ static int subdev_fh_init(struct v4l2_subdev_fh *fh,
>> struct v4l2_subdev *sd) static void subdev_fh_free(struct v4l2_subdev_fh
>> *fh)
>>  {
>>  #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
>> -	kfree(fh->try_fmt);
>> -	fh->try_fmt = NULL;
>> -	fh->try_crop = NULL;
>> +	kfree(fh->pad);
>> +	fh->pad = NULL;
>>  #endif
>>  }
>>
>> @@ -293,6 +287,26 @@ static long subdev_do_ioctl(struct file *file, unsigned
>> int cmd, void *arg) return v4l2_subdev_call(sd, pad, enum_frame_interval,
>> subdev_fh, fie);
>>  	}
>> +
>> +	case VIDIOC_SUBDEV_G_SELECTION: {
>> +		struct v4l2_subdev_selection *sel = arg;
>> +
>> +		if (sel->pad >= sd->entity.num_pads)
>> +			return -EINVAL;
> 
> Shouldn't you verify the which field as well, as done for the crop ioctls ?

I thought I got a comment on that and fixed it, but apparently not. :-P
Thanks for pointing this out.

>> +
>> +		return v4l2_subdev_call(
>> +			sd, pad, get_selection, subdev_fh, sel);
>> +	}
>> +
>> +	case VIDIOC_SUBDEV_S_SELECTION: {
>> +		struct v4l2_subdev_selection *sel = arg;
>> +

Fixed it here as well...

>> +		if (sel->pad >= sd->entity.num_pads)
>> +			return -EINVAL;
>> +
>> +		return v4l2_subdev_call(
>> +			sd, pad, set_selection, subdev_fh, sel);
>> +	}
>>  #endif
>>  	default:
>>  		return v4l2_subdev_call(sd, core, ioctl, cmd, arg);
>> diff --git a/include/linux/v4l2-subdev.h b/include/linux/v4l2-subdev.h
>> index ed29cbb..6c84390 100644
>> --- a/include/linux/v4l2-subdev.h
>> +++ b/include/linux/v4l2-subdev.h
>> @@ -123,6 +123,43 @@ struct v4l2_subdev_frame_interval_enum {
>>  	__u32 reserved[9];
>>  };
>>
>> +#define V4L2_SUBDEV_SEL_FLAG_SIZE_GE			(1 << 0)
>> +#define V4L2_SUBDEV_SEL_FLAG_SIZE_LE			(1 << 1)
>> +#define V4L2_SUBDEV_SEL_FLAG_KEEP_CONFIG		(1 << 2)
>> +
>> +/* active cropping area */
>> +#define V4L2_SUBDEV_SEL_TGT_CROP_ACTIVE			0x0000
>> +/* cropping bounds */
>> +#define V4L2_SUBDEV_SEL_TGT_CROP_BOUNDS			0x0002
>> +/* current composing area */
>> +#define V4L2_SUBDEV_SEL_TGT_COMPOSE_ACTIVE		0x0100
>> +/* composing bounds */
>> +#define V4L2_SUBDEV_SEL_TGT_COMPOSE_BOUNDS		0x0102
>> +
>> +
>> +/**
>> + * struct v4l2_subdev_selection - selection info
>> + *
>> + * @which: either V4L2_SUBDEV_FORMAT_ACTIVE or V4L2_SUBDEV_FORMAT_TRY
>> + * @pad: pad number, as reported by the media API
>> + * @target: selection target, used to choose one of possible rectangles
>> + * @flags: constraint flags
>> + * @r: coordinates of the selection window
>> + * @reserved: for future use, rounds structure size to 64 bytes, set to
>> zero
> 
> I'm not sure we need to mention that the reserved fields round the structure 
> size to 64 bytes.

Fixed.

>> + *
>> + * Hardware may use multiple helper windows to process a video stream.
>> + * The structure is used to exchange this selection areas between
>> + * an application and a driver.
>> + */
>> +struct v4l2_subdev_selection {
>> +	__u32 which;
>> +	__u32 pad;
>> +	__u32 target;
>> +	__u32 flags;
>> +	struct v4l2_rect r;
>> +	__u32 reserved[8];
>> +};
>> +
>>  #define VIDIOC_SUBDEV_G_FMT	_IOWR('V',  4, struct v4l2_subdev_format)
>>  #define VIDIOC_SUBDEV_S_FMT	_IOWR('V',  5, struct v4l2_subdev_format)
>>  #define VIDIOC_SUBDEV_G_FRAME_INTERVAL \
>> @@ -137,5 +174,9 @@ struct v4l2_subdev_frame_interval_enum {
>>  			_IOWR('V', 75, struct v4l2_subdev_frame_interval_enum)
>>  #define VIDIOC_SUBDEV_G_CROP	_IOWR('V', 59, struct v4l2_subdev_crop)
>>  #define VIDIOC_SUBDEV_S_CROP	_IOWR('V', 60, struct v4l2_subdev_crop)
>> +#define VIDIOC_SUBDEV_G_SELECTION \
>> +	_IOWR('V', 61, struct v4l2_subdev_selection)
>> +#define VIDIOC_SUBDEV_S_SELECTION \
>> +	_IOWR('V', 62, struct v4l2_subdev_selection)
>>
>>  #endif
>> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
>> index f0f3358..feab950 100644
>> --- a/include/media/v4l2-subdev.h
>> +++ b/include/media/v4l2-subdev.h
>> @@ -466,6 +466,10 @@ struct v4l2_subdev_pad_ops {
>>  		       struct v4l2_subdev_crop *crop);
>>  	int (*get_crop)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,
>>  		       struct v4l2_subdev_crop *crop);
>> +	int (*get_selection)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,
>> +			     struct v4l2_subdev_selection *sel);
>> +	int (*set_selection)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,
>> +			     struct v4l2_subdev_selection *sel);
>>  };
>>
>>  struct v4l2_subdev_ops {
>> @@ -549,8 +553,11 @@ struct v4l2_subdev {
>>  struct v4l2_subdev_fh {
>>  	struct v4l2_fh vfh;
>>  #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
>> -	struct v4l2_mbus_framefmt *try_fmt;
>> -	struct v4l2_rect *try_crop;
>> +	struct {
>> +		struct v4l2_mbus_framefmt try_fmt;
>> +		struct v4l2_rect try_crop;
>> +		struct v4l2_rect try_compose;
>> +	} *pad;
>>  #endif
>>  };
>>
>> @@ -561,13 +568,19 @@ struct v4l2_subdev_fh {
>>  static inline struct v4l2_mbus_framefmt *
>>  v4l2_subdev_get_try_format(struct v4l2_subdev_fh *fh, unsigned int pad)
>>  {
>> -	return &fh->try_fmt[pad];
>> +	return &fh->pad[pad].try_fmt;
>>  }
>>
>>  static inline struct v4l2_rect *
>>  v4l2_subdev_get_try_crop(struct v4l2_subdev_fh *fh, unsigned int pad)
>>  {
>> -	return &fh->try_crop[pad];
>> +	return &fh->pad[pad].try_crop;
>> +}
>> +
>> +static inline struct v4l2_rect *
>> +v4l2_subdev_get_try_compose(struct v4l2_subdev_fh *fh, unsigned int pad)
>> +{
>> +	return &fh->pad[pad].try_compose;
>>  }
>>  #endif


-- 
Sakari Ailus
sakari.ailus@iki.fi