Hello Hans
I have just posted a new patch that only takes care of the core.
Thanks!
On Mon, Sep 30, 2013 at 2:11 PM, Hans Verkuil <hverkuil@xxxxxxxxx> wrote:
> On 09/30/2013 01:17 PM, Ricardo Ribalda Delgado wrote:
>> Hello Hans
>>
>> As allways thank you very much for your comments.
>>
>> On Mon, Sep 30, 2013 at 12:21 PM, Hans Verkuil <hverkuil@xxxxxxxxx> wrote:
>>> Hi Ricardo,
>>>
>>> Sorry for the delayed review, but I'm finally catching up with my backlog.
>>>
>>> I've got a number of comments regarding this patch. I'm ignoring the platform
>>> driver patches for now until the core support is correct.
>>>
>>> On 09/16/2013 02:54 PM, Ricardo Ribalda Delgado wrote:
>>>> From: Ricardo Ribalda <ricardo.ribalda@xxxxxxxxx>
>>>>
>>>> Extend v4l2 selection API to support multiple selection areas, this way
>>>> sensors that support multiple readout areas can work with multiple areas
>>>> of insterest.
>>>>
>>>> The struct v4l2_selection and v4l2_subdev_selection has been extented
>>>> with a new field rectangles. If it is value is different than zero the
>>>> pr array is used instead of the r field.
>>>>
>>>> A new structure v4l2_ext_rect has been defined, containing 4 reserved
>>>> fields for future improvements, as suggested by Hans.
>>>>
>>>> A new function in v4l2-comon (v4l2_selection_flat_struct) is in charge
>>>> of converting a pr pointer with one item to a flatten struct. This
>>>> function is used in all the old drivers that dont support multiple
>>>> selections.
>>>>
>>>> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx>
>>>> ---
>>>> drivers/media/platform/exynos-gsc/gsc-m2m.c | 6 +++
>>>> drivers/media/platform/exynos4-is/fimc-capture.c | 6 +++
>>>> drivers/media/platform/exynos4-is/fimc-lite.c | 6 +++
>>>> drivers/media/platform/s3c-camif/camif-capture.c | 6 +++
>>>> drivers/media/platform/s5p-jpeg/jpeg-core.c | 3 ++
>>>> drivers/media/platform/s5p-tv/mixer_video.c | 6 +++
>>>> drivers/media/platform/soc_camera/soc_camera.c | 6 +++
>>>> drivers/media/v4l2-core/v4l2-common.c | 13 ++++++
>>>> drivers/media/v4l2-core/v4l2-ioctl.c | 54 +++++++++++++++++++++---
>>>> include/media/v4l2-common.h | 2 +
>>>> include/uapi/linux/v4l2-subdev.h | 10 ++++-
>>>> include/uapi/linux/videodev2.h | 15 ++++++-
>>>> 12 files changed, 122 insertions(+), 11 deletions(-)
>>>>
>>>
>>> <snip>
>>>
>>>> diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
>>>> index a95e5e2..cd20567 100644
>>>> --- a/drivers/media/v4l2-core/v4l2-common.c
>>>> +++ b/drivers/media/v4l2-core/v4l2-common.c
>>>> @@ -886,3 +886,16 @@ void v4l2_get_timestamp(struct timeval *tv)
>>>> tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC;
>>>> }
>>>> EXPORT_SYMBOL_GPL(v4l2_get_timestamp);
>>>> +
>>>> +int v4l2_selection_flat_struct(struct v4l2_selection *s)
>>>> +{
>>>> + if (s->rectangles == 0)
>>>> + return 0;
>>>> +
>>>> + if (s->rectangles != 1)
>>>> + return -EINVAL;
>>>> +
>>>> + s->r = s->pr[0].r;
>>>
>>> This would overwrite the pr pointer. Not a good idea.
>>
>> That was exactly the point. The helper function convert the
>> multi_selection, ext_rect to the legacy struct. This way the drivers
>> needed almost no modification, just a call to the helper at the
>> beginning of the handler.
>
> That doesn't work: G and S_SELECTION are IOWR, so the driver can modify the
> rectangles and those will have to be passed back to userspace. So you cannot
> just change the contents of struct v4l2_selection.
>
>>
>> Otherwise we need your get_rect helper, and then a set_rect helper at
>> every exit.
>>
>> If you think this is the way, then lets do it. Right now there are not
>> too many drivers that supports selection, so it is right time to make
>> such a decisions.
>>
>>>
>>> I would make a helper function like this:
>>>
>>> int v4l2_selection_get_rect(struct v4l2_selection *s, struct v4l2_ext_rect *r)
>>> {
>>> if (s->rectangles > 1)
>>> return -EINVAL;
>>> if (s->rectangles == 1) {
>>> *r = s->pr[0];
>>> return 0;
>>> }
>>> if (s->r.width < 0 || s->r.height < 0)
>>> return -EINVAL;
>>> r->left = s->r.left;
>>> r->top = s->r.top;
>>> r->width = s->r.width;
>>> r->height = s->r.height;
>>> memset(r->reserved, 0, sizeof(r->reserved));
>>> return 0;
>>> }
>>>
>>> See also my proposed v4l2_ext_rect definition below.
>>>
>>>> + return 0;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(v4l2_selection_flat_struct);
>>>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> index 68e6b5e..fe92f6b 100644
>>>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> @@ -572,11 +572,22 @@ static void v4l_print_crop(const void *arg, bool write_only)
>>>> static void v4l_print_selection(const void *arg, bool write_only)
>>>> {
>>>> const struct v4l2_selection *p = arg;
>>>> + int i;
>>>>
>>>> - pr_cont("type=%s, target=%d, flags=0x%x, wxh=%dx%d, x,y=%d,%d\n",
>>>> - prt_names(p->type, v4l2_type_names),
>>>> - p->target, p->flags,
>>>> - p->r.width, p->r.height, p->r.left, p->r.top);
>>>> + if (p->rectangles == 0)
>>>> + pr_cont("type=%s, target=%d, flags=0x%x, wxh=%dx%d, x,y=%d,%d\n",
>>>> + prt_names(p->type, v4l2_type_names),
>>>> + p->target, p->flags,
>>>> + p->r.width, p->r.height, p->r.left, p->r.top);
>>>> + else{
>>>> + pr_cont("type=%s, target=%d, flags=0x%x rectangles=%d\n",
>>>> + prt_names(p->type, v4l2_type_names),
>>>> + p->target, p->flags, p->rectangles);
>>>> + for (i = 0; i < p->rectangles; i++)
>>>> + pr_cont("rectangle %d: wxh=%dx%d, x,y=%d,%d\n",
>>>> + i, p->r.width, p->r.height,
>>>> + p->r.left, p->r.top);
>>>> + }
>>>> }
>>>>
>>>> static void v4l_print_jpegcompression(const void *arg, bool write_only)
>>>> @@ -1645,6 +1656,7 @@ static int v4l_g_crop(const struct v4l2_ioctl_ops *ops,
>>>> struct v4l2_crop *p = arg;
>>>> struct v4l2_selection s = {
>>>> .type = p->type,
>>>> + .rectangles = 0,
>>>
>>> No need for this. In initializers like this fields that aren't initialized
>>> explicitly will be zeroed by the compiler.
>>>
>>>> };
>>>> int ret;
>>>>
>>>> @@ -1673,6 +1685,7 @@ static int v4l_s_crop(const struct v4l2_ioctl_ops *ops,
>>>> struct v4l2_selection s = {
>>>> .type = p->type,
>>>> .r = p->c,
>>>> + .rectangles = 0,
>>>> };
>>>>
>>>> if (ops->vidioc_s_crop)
>>>> @@ -1692,7 +1705,10 @@ static int v4l_cropcap(const struct v4l2_ioctl_ops *ops,
>>>> struct file *file, void *fh, void *arg)
>>>> {
>>>> struct v4l2_cropcap *p = arg;
>>>> - struct v4l2_selection s = { .type = p->type };
>>>> + struct v4l2_selection s = {
>>>> + .type = p->type,
>>>> + .rectangles = 0,
>>>> + };
>>>> int ret;
>>>>
>>>> if (ops->vidioc_cropcap)
>>>> @@ -1726,6 +1742,30 @@ static int v4l_cropcap(const struct v4l2_ioctl_ops *ops,
>>>> return 0;
>>>> }
>>>>
>>>> +static int v4l_s_selection(const struct v4l2_ioctl_ops *ops,
>>>> + struct file *file, void *fh, void *arg)
>>>> +{
>>>> + struct v4l2_selection *s = arg;
>>>> +
>>>> + if (s->rectangles &&
>>>> + !access_ok(VERIFY_READ, s->pr, s->rectangles * sizeof(*s->pr)))
>>>> + return -EFAULT;
>>>
>>> No, this isn't necessary. Instead add support for the selection array to
>>> check_array_args() in v4l2-ioctl.c. That's where this should be handled.
>>> video_usercopy() will then do the copy_from/to_user for you and drivers don't
>>> need to care about it.
>>>
>>> Note that you also need to update v4l2-compat-ioctl32.c!
>>>
>>>> +
>>>> + return ops->vidioc_s_selection(file, fh, s);
>>>> +}
>>>> +
>>>> +static int v4l_g_selection(const struct v4l2_ioctl_ops *ops,
>>>> + struct file *file, void *fh, void *arg)
>>>> +{
>>>> + struct v4l2_selection *s = arg;
>>>> +
>>>> + if (s->rectangles &&
>>>> + !access_ok(VERIFY_WRITE, s->pr, s->rectangles * sizeof(*s->pr)))
>>>> + return -EFAULT;
>>>> +
>>>> + return ops->vidioc_g_selection(file, fh, s);
>>>> +}
>>>> +
>>>> static int v4l_log_status(const struct v4l2_ioctl_ops *ops,
>>>> struct file *file, void *fh, void *arg)
>>>> {
>>>> @@ -2018,8 +2058,8 @@ static struct v4l2_ioctl_info v4l2_ioctls[] = {
>>>> IOCTL_INFO_FNC(VIDIOC_CROPCAP, v4l_cropcap, v4l_print_cropcap, INFO_FL_CLEAR(v4l2_cropcap, type)),
>>>> IOCTL_INFO_FNC(VIDIOC_G_CROP, v4l_g_crop, v4l_print_crop, INFO_FL_CLEAR(v4l2_crop, type)),
>>>> IOCTL_INFO_FNC(VIDIOC_S_CROP, v4l_s_crop, v4l_print_crop, INFO_FL_PRIO),
>>>> - IOCTL_INFO_STD(VIDIOC_G_SELECTION, vidioc_g_selection, v4l_print_selection, 0),
>>>> - IOCTL_INFO_STD(VIDIOC_S_SELECTION, vidioc_s_selection, v4l_print_selection, INFO_FL_PRIO),
>>>> + IOCTL_INFO_FNC(VIDIOC_G_SELECTION, v4l_g_selection, v4l_print_selection, 0),
>>>> + IOCTL_INFO_FNC(VIDIOC_S_SELECTION, v4l_s_selection, v4l_print_selection, INFO_FL_PRIO),
>>>> IOCTL_INFO_STD(VIDIOC_G_JPEGCOMP, vidioc_g_jpegcomp, v4l_print_jpegcompression, 0),
>>>> IOCTL_INFO_STD(VIDIOC_S_JPEGCOMP, vidioc_s_jpegcomp, v4l_print_jpegcompression, INFO_FL_PRIO),
>>>> IOCTL_INFO_FNC(VIDIOC_QUERYSTD, v4l_querystd, v4l_print_std, 0),
>>>> diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
>>>> index 015ff82..b0a3d2b 100644
>>>> --- a/include/media/v4l2-common.h
>>>> +++ b/include/media/v4l2-common.h
>>>> @@ -216,4 +216,6 @@ struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait);
>>>>
>>>> void v4l2_get_timestamp(struct timeval *tv);
>>>>
>>>> +int v4l2_selection_flat_struct(struct v4l2_selection *s);
>>>> +
>>>> #endif /* V4L2_COMMON_H_ */
>>>> diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
>>>> index a33c4da..b5ee08b 100644
>>>> --- a/include/uapi/linux/v4l2-subdev.h
>>>> +++ b/include/uapi/linux/v4l2-subdev.h
>>>> @@ -133,6 +133,8 @@ struct v4l2_subdev_frame_interval_enum {
>>>> * defined in v4l2-common.h; V4L2_SEL_TGT_* .
>>>> * @flags: constraint flags, defined in v4l2-common.h; V4L2_SEL_FLAG_*.
>>>> * @r: coordinates of the selection window
>>>> + * @pr: array of rectangles containing the selection windows
>>>> + * @rectangles: Number of rectangles in pr structure. If zero, r is used instead
>>>> * @reserved: for future use, set to zero for now
>>>> *
>>>> * Hardware may use multiple helper windows to process a video stream.
>>>> @@ -144,8 +146,12 @@ struct v4l2_subdev_selection {
>>>> __u32 pad;
>>>> __u32 target;
>>>> __u32 flags;
>>>> - struct v4l2_rect r;
>>>> - __u32 reserved[8];
>>>> + union{
>>>
>>> Add space after 'union'.
>>>
>>>> + struct v4l2_rect r;
>>>> + struct v4l2_ext_rect *pr;
>>>> + };
>>>> + __u32 rectangles;
>>>> + __u32 reserved[7];
>>>> };
>>>
>>> I suspect this should get the packed attribute. It's a good idea anyone to add that,
>>> but we have to check that the sizeof(struct v4l2_subdev_selection) doesn't change
>>> for both 32 and 64 bit compilations.
>>>
>>>>
>>>> struct v4l2_subdev_edid {
>>>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>>>> index 95ef455..db8b1a5 100644
>>>> --- a/include/uapi/linux/videodev2.h
>>>> +++ b/include/uapi/linux/videodev2.h
>>>> @@ -211,6 +211,11 @@ struct v4l2_rect {
>>>> __s32 height;
>>>> };
>>>>
>>>> +struct v4l2_ext_rect {
>>>> + struct v4l2_rect r;
>>>> + __u32 reserved[4];
>>>> +};
>>>
>>> I actually would prefer this:
>>>
>>> struct v4l2_ext_rect {
>>> __s32 left;
>>> __s32 top;
>>> __u32 width;
>>> __u32 height;
>>> __u32 reserved[4];
>>> };
>>>
>>> It has always annoyed me that width and height were signed, and this fixes that problem.
>>
>> Just one comment. On the bmp standard a negative height means that the
>> image is upside down. With multiple selections it could be a nice
>> thing to allow such a behavious, so one selection can be inverted (if
>> all are inverted, I guess vflip is more correct).
>
> Negative width/height values are completely out of spec. No driver supports that, and
> as you say, we have vflip/hflip for mirroring.
>
> Regards,
>
> Hans
>
>>
>>>
>>> This is also why I was using v4l2_ext_rect in the selection helper function: that way
>>> drivers do not need to check for negative width/height values.
>>>
>>>> +
>>>> struct v4l2_fract {
>>>> __u32 numerator;
>>>> __u32 denominator;
>>>> @@ -804,6 +809,8 @@ struct v4l2_crop {
>>>> * defined in v4l2-common.h; V4L2_SEL_TGT_* .
>>>> * @flags: constraints flags, defined in v4l2-common.h; V4L2_SEL_FLAG_*.
>>>> * @r: coordinates of selection window
>>>> + * @pr: array of rectangles containing the selection windows
>>>> + * @rectangles: Number of rectangles in pr structure. If zero, r is used instead
>>>> * @reserved: for future use, rounds structure size to 64 bytes, set to zero
>>>> *
>>>> * Hardware may use multiple helper windows to process a video stream.
>>>> @@ -814,8 +821,12 @@ struct v4l2_selection {
>>>> __u32 type;
>>>> __u32 target;
>>>> __u32 flags;
>>>> - struct v4l2_rect r;
>>>> - __u32 reserved[9];
>>>> + union{
>>>
>>> Add space after 'union'.
>>>
>>>> + struct v4l2_rect r;
>>>> + struct v4l2_ext_rect *pr;
>>>> + };
>>>> + __u32 rectangles;
>>>> + __u32 reserved[8];
>>>> };
>>>>
>>>>
>>>>
>
--
Ricardo Ribalda
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
