Re: [RFC PATCH v6 02/11] media: v4l2: Extend pixel formats to unify single/multi-planar handling (and more)

Hans Verkuil
2022-11-07T08:42:44Z

Hi Hsia-Jun,

Helen no longer works for Collabora and left the community. I've added her latest email.

Helen, are you still interested in hearing about this?

Regards,

Hans

On 05/11/2022 16:19, Hsia-Jun Li wrote:
> Hello Helen
>
> I didn't see any updates from V6 and V7-WIP in your repo. That is what I need to for our complex tile formats in our platform.
>
> Any future plane here?
>
> Besides I have some ideas on these patches.
>
> On 2/24/21 23:12, Helen Koike wrote:
>> Hi Hans,
>>
>> Thank you for your comment, please see my reply below.
>>
>> On 2/23/21 9:35 AM, Hans Verkuil wrote:
>>> Hi Helen,
>>>
>>> On 14/01/2021 19:07, Helen Koike wrote:
>>>> This is part of the multiplanar and singleplanar unification process.
>>>> v4l2_ext_pix_format is supposed to work for both cases.
>>>>
>>>> We also add the concept of modifiers already employed in DRM to expose
>>>> HW-specific formats (like tiled or compressed formats) and allow
>>>> exchanging this information with the DRM subsystem in a consistent way.
>>>>
>>>> Note that only V4L2_BUF_TYPE_VIDEO_[OUTPUT,CAPTURE] are accepted in
>>>> v4l2_ext_format, other types will be rejected if you use the
>>>> {G,S,TRY}_EXT_PIX_FMT ioctls.
>>>>
>>>> New hooks have been added to v4l2_ioctl_ops to support those new ioctls
>>>> in drivers, but, in the meantime, the core takes care of converting
>>>> {S,G,TRY}_EXT_PIX_FMT requests into {S,G,TRY}_FMT so that old drivers can
>>>> still work if the userspace app/lib uses the new ioctls.
>>>>
>>>> The conversion is also done the other around to allow userspace
>>>> apps/libs using {S,G,TRY}_FMT to work with drivers implementing the
>>>> _ext_ hooks.
>>>
>>> I have some small comments below, but also one high level comment:
>>>
>>> Regarding M variants of pixelformats: this patch 'normalizes' them to
>>> regular pixelformats in the extended API. This makes life complicated,
>>> and I wonder if this is the right approach.
>>>
>>> Currently there are two reasons for a driver to support e.g. NV12M:
>>> either luma and chroma need to be in two memory banks, or the luma
>>> and chroma planes cannot be contiguous due to alignment requirements.
>>>
>>> The first requirement is still valid for drivers that support the extended API.
>>> The second requirement is no longer a reason to support NV12M. But I
>>> don't think we should just drop NV12M support if it was already supported
>>> before the conversion to this extended API. Since NV12M allocates two buffers
>>> instead of one, it is still different from a regular NV12.
>>
>> I don't see what would be the difference when using NV12 and NV12M in Ext API.
>> NV12 could be used for both requirements. It would even allow the second
>> requirement with a single memory buffer.
>>
> Although I don't have problem here to support both single and multiple planes in our hardware. But using the single plane format here is not convience for us.
>
> The tile format in our platform is little complex, you can't calculate the stride and sizeimage easily with just the modifier, width and height. Then we don't have a good place to record the offset here.
>
> Besides, the luma and chroma planes would always need their own compression meta data planes. If we use NV12 here, that would make a very strange pixel format, one plane for the pixel datas and two
> planes for the meta data.
>
>>>
>>> I would prefer that such drivers support both NV12 and NV12M, so no
>>> automatic conversion.
>>>
>>> A related question is how to handle pixelformat enumeration: with the
>>> extended API an NV12 format might work, but not with the old API (e.g.
>>> due to memory alignment requirements). I wonder if a VIDIOC_ENUM_EXT_PIX_FMT
>>> isn't needed.
>>
>> We need VIDIOC_ENUM_EXT_PIX_FMT for modifiers, but we can add it later.
>> If the driver reports NV12M, userspace can use it and the framework
>> normilizes it.
>>
>>>
>>> VIDIOC_ENUM_EXT_PIX_FMT would report NV12 and NV12M, while VIDIOC_ENUM_FMT
>>> would just report NV12M.
>>
>> If NV12 and NV12M are equivalent in Ext API, I don't see why we would
>> report both (unless I'm missing something, which is probably the case).
>>
>> The idea was to deprecate the M-variants one day.
> I was thinking the way in DRM API is better, always assuming it would always in a multiple planes. The only problem is we don't have a way to let the allocator that allocate contiguous memory for
> planes when we need to do that.
>>
>> Regards,
>> Helen
>>
>>>
>>>>
>>>> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
>>>> Signed-off-by: Helen Koike <helen.koike@collabora.com>
>>>> ---
>>>>
>>>> Changes in v6:
>>>>   The main change here was fixing the conversion, so planes reflects color planes,
>>>>   and to implement this properly I made major refactors compared to the previous
>>>>   version.
>>>> - struct v4l2_plane_ext_pix_format removed, using struct v4l2_plane_pix_format instead (Tomasz)
>>>> - refer to drm_fourcc.h in struct v4l2_ext_pix_format docs (Hans)
>>>> - reorder colorimetry fields in struct v4l2_ext_pix_format (Hans)
>>>> - do not set Ext ioctls as valid for vid_out_overlay (Tomasz)
>>>> - refactor conversion functions, so planes are color planes (Tomasz)
>>>> - Don't explicitly check for e->modifier != 0 in v4l2_ext_pix_format_to_format() (Tomasz)
>>>> - Use "ef" for extended formats in the framework for consistency (Tomasz)
>>>> - Handle xfer_func field in conversions (Tomasz)
>>>> - Zero reserved fields in v4l_s_ext_pix_fmt() and v4l_try_ext_pix_fmt() (Tomasz)
>>>> - Refactor format functions to use v4l_fmt_ioctl_via_ext()
>>>> - Several fixes/refactoring/changes
>>>> - Remove EXT API for touch devices
>>>>
>>>> Changes in v5:
>>>> - change sizes and reorder fields to avoid holes in the struct and make
>>>>    it the same for 32 and 64 bits
>>>> - removed __attribute__ ((packed)) from uapi structs
>>>> - Fix doc warning from make htmldocs
>>>> - Updated commit message with EXT_PIX prefix for the ioctls.
>>>>
>>>> Changes in v4:
>>>> - Use v4l2_ext_pix_format directly in the ioctl, drop v4l2_ext_format,
>>>> making V4L2_BUF_TYPE_VIDEO_[OUTPUT,CAPTURE] the only valid types.
>>>> - Add reserved fields
>>>> - Removed num_planes from struct v4l2_ext_pix_format
>>>> - Removed flag field from struct v4l2_ext_pix_format, since the only
>>>>    defined value is V4L2_PIX_FMT_FLAG_PREMUL_ALPHA only used by vsp1,
>>>>    where we can use modifiers, or add it back later through the reserved
>>>>    bits.
>>>> - In v4l2_ext_format_to_format(), check if modifier is != MOD_LINEAR &&
>>>>    != MOD_INVALID
>>>> - Fix type assignment in v4l_g_fmt_ext_pix()
>>>> - Rebased on top of media/master (post 5.8-rc1)
>>>>
>>>> Changes in v3:
>>>> - Rebased on top of media/master (post 5.4-rc1)
>>>>
>>>> Changes in v2:
>>>> - Move the modifier in v4l2_ext_format (was formerly placed in
>>>>    v4l2_ext_plane)
>>>> - Fix a few bugs in the converters and add a strict parameter to
>>>>    allow conversion of uninitialized/mis-initialized objects
>>>> ---
>>>>   drivers/media/v4l2-core/v4l2-dev.c   |  27 +-
>>>>   drivers/media/v4l2-core/v4l2-ioctl.c | 538 +++++++++++++++++++++++++--
>>>>   include/media/v4l2-ioctl.h           |  28 ++
>>>>   include/uapi/linux/videodev2.h       |  41 ++
>>>>   4 files changed, 602 insertions(+), 32 deletions(-)
>>>>
>>>> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
>>>> index f9cff033d0dc..5add58cb6d45 100644
>>>> --- a/drivers/media/v4l2-core/v4l2-dev.c
>>>> +++ b/drivers/media/v4l2-core/v4l2-dev.c
>>>> @@ -608,27 +608,42 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>>>                      ops->vidioc_enum_fmt_vid_overlay)) ||
>>>>               (is_tx && ops->vidioc_enum_fmt_vid_out))
>>>>               set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
>>>> +        if ((is_rx && ops->vidioc_g_fmt_vid_overlay) ||
>>>> +            (is_tx && ops->vidioc_g_fmt_vid_out_overlay))
>>>> +             set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
>>>>           if ((is_rx && (ops->vidioc_g_fmt_vid_cap ||
>>>>                      ops->vidioc_g_fmt_vid_cap_mplane ||
>>>> -                   ops->vidioc_g_fmt_vid_overlay)) ||
>>>> +                   ops->vidioc_g_ext_pix_fmt_vid_cap)) ||
>>>>               (is_tx && (ops->vidioc_g_fmt_vid_out ||
>>>>                      ops->vidioc_g_fmt_vid_out_mplane ||
>>>> -                   ops->vidioc_g_fmt_vid_out_overlay)))
>>>> +                   ops->vidioc_g_ext_pix_fmt_vid_out))) {
>>>>                set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
>>>> +             set_bit(_IOC_NR(VIDIOC_G_EXT_PIX_FMT), valid_ioctls);
>>>> +        }
>>>> +        if ((is_rx && ops->vidioc_s_fmt_vid_overlay) ||
>>>> +            (is_tx && ops->vidioc_s_fmt_vid_out_overlay))
>>>> +             set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
>>>>           if ((is_rx && (ops->vidioc_s_fmt_vid_cap ||
>>>>                      ops->vidioc_s_fmt_vid_cap_mplane ||
>>>> -                   ops->vidioc_s_fmt_vid_overlay)) ||
>>>> +                   ops->vidioc_s_ext_pix_fmt_vid_cap)) ||
>>>>               (is_tx && (ops->vidioc_s_fmt_vid_out ||
>>>>                      ops->vidioc_s_fmt_vid_out_mplane ||
>>>> -                   ops->vidioc_s_fmt_vid_out_overlay)))
>>>> +                   ops->vidioc_s_ext_pix_fmt_vid_out))) {
>>>>                set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
>>>> +             set_bit(_IOC_NR(VIDIOC_S_EXT_PIX_FMT), valid_ioctls);
>>>> +        }
>>>> +        if ((is_rx && ops->vidioc_try_fmt_vid_overlay) ||
>>>> +            (is_tx && ops->vidioc_try_fmt_vid_out_overlay))
>>>> +             set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
>>>>           if ((is_rx && (ops->vidioc_try_fmt_vid_cap ||
>>>>                      ops->vidioc_try_fmt_vid_cap_mplane ||
>>>> -                   ops->vidioc_try_fmt_vid_overlay)) ||
>>>> +                   ops->vidioc_try_ext_pix_fmt_vid_cap)) ||
>>>>               (is_tx && (ops->vidioc_try_fmt_vid_out ||
>>>>                      ops->vidioc_try_fmt_vid_out_mplane ||
>>>> -                   ops->vidioc_try_fmt_vid_out_overlay)))
>>>> +                   ops->vidioc_try_ext_pix_fmt_vid_out))) {
>>>>                set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
>>>> +             set_bit(_IOC_NR(VIDIOC_TRY_EXT_PIX_FMT), valid_ioctls);
>>>> +        }
>>>>           SET_VALID_IOCTL(ops, VIDIOC_OVERLAY, vidioc_overlay);
>>>>           SET_VALID_IOCTL(ops, VIDIOC_G_FBUF, vidioc_g_fbuf);
>>>>           SET_VALID_IOCTL(ops, VIDIOC_S_FBUF, vidioc_s_fbuf);
>>>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> index 848286a284f6..a9c07c0a73ec 100644
>>>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> @@ -18,6 +18,8 @@
>>>>   #include <linux/videodev2.h>
>>>> +#include <drm/drm_fourcc.h>
>>>> +
>>>>   #include <media/v4l2-common.h>
>>>>   #include <media/v4l2-ioctl.h>
>>>>   #include <media/v4l2-ctrls.h>
>>>> @@ -38,6 +40,11 @@
>>>>   #define is_valid_ioctl(vfd, cmd) test_bit(_IOC_NR(cmd), (vfd)->valid_ioctls)
>>>> +#define V4L2_IS_CAP_MULTIPLANAR(vdev)    (vdev->device_caps & \
>>>> +                     (V4L2_CAP_VIDEO_CAPTURE_MPLANE | \
>>>> +                     V4L2_CAP_VIDEO_OUTPUT_MPLANE | \
>>>> +                     V4L2_CAP_VIDEO_M2M_MPLANE))
>>>> +
>>>>   struct std_descr {
>>>>       v4l2_std_id std;
>>>>       const char *descr;
>>>> @@ -379,6 +386,27 @@ static void v4l_print_format(const void *arg, bool write_only)
>>>>       }
>>>>   }
>>>> +static void v4l_print_ext_pix_format(const void *arg, bool write_only)
>>>> +{
>>>> +    const struct v4l2_ext_pix_format *ef = arg;
>>>> +    unsigned int i;
>>>> +
>>>> +    pr_cont("type=%s, width=%u, height=%u, format=%c%c%c%c, modifier %llx, field=%s, colorspace=%d, ycbcr_enc=%u, quantization=%u, xfer_func=%u\n",
>>>> +        prt_names(ef->type, v4l2_type_names),
>>>> +        ef->width, ef->height,
>>>> +        (ef->pixelformat & 0xff),
>>>> +        (ef->pixelformat >>  8) & 0xff,
>>>> +        (ef->pixelformat >> 16) & 0xff,
>>>> +        (ef->pixelformat >> 24) & 0xff,
>>>> +        ef->modifier, prt_names(ef->field, v4l2_field_names),
>>>> +        ef->colorspace, ef->ycbcr_enc,
>>>> +        ef->quantization, ef->xfer_func);
>>>> +    for (i = 0; i < VIDEO_MAX_PLANES && ef->plane_fmt[i].sizeimage; i++)
>>>> +        pr_debug("plane %u: bytesperline=%u sizeimage=%u\n",
>>>> +             i, ef->plane_fmt[i].bytesperline,
>>>> +             ef->plane_fmt[i].sizeimage);
>>>> +}
>>>> +
>>>>   static void v4l_print_framebuffer(const void *arg, bool write_only)
>>>>   {
>>>>       const struct v4l2_framebuffer *p = arg;
>>>> @@ -963,11 +991,15 @@ static int check_fmt(struct file *file, enum v4l2_buf_type type)
>>>>       switch (type) {
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>>           if ((is_vid || is_tch) && is_rx &&
>>>> -            (ops->vidioc_g_fmt_vid_cap || ops->vidioc_g_fmt_vid_cap_mplane))
>>>> +            (ops->vidioc_g_fmt_vid_cap ||
>>>> +             ops->vidioc_g_ext_pix_fmt_vid_cap ||
>>>> +             ops->vidioc_g_fmt_vid_cap_mplane))
>>>>               return 0;
>>>>           break;
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>> -        if ((is_vid || is_tch) && is_rx && ops->vidioc_g_fmt_vid_cap_mplane)
>>>> +        if ((is_vid || is_tch) && is_rx &&
>>>> +            (ops->vidioc_g_fmt_vid_cap_mplane ||
>>>> +             ops->vidioc_g_ext_pix_fmt_vid_cap))
>>>>               return 0;
>>>>           break;
>>>>       case V4L2_BUF_TYPE_VIDEO_OVERLAY:
>>>> @@ -976,11 +1008,15 @@ static int check_fmt(struct file *file, enum v4l2_buf_type type)
>>>>           break;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>>           if (is_vid && is_tx &&
>>>> -            (ops->vidioc_g_fmt_vid_out || ops->vidioc_g_fmt_vid_out_mplane))
>>>> +            (ops->vidioc_g_fmt_vid_out ||
>>>> +             ops->vidioc_g_ext_pix_fmt_vid_out ||
>>>> +             ops->vidioc_g_fmt_vid_out_mplane))
>>>>               return 0;
>>>>           break;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>>>> -        if (is_vid && is_tx && ops->vidioc_g_fmt_vid_out_mplane)
>>>> +        if (is_vid && is_tx &&
>>>> +            (ops->vidioc_g_ext_pix_fmt_vid_out ||
>>>> +             ops->vidioc_g_fmt_vid_out_mplane))
>>>>               return 0;
>>>>           break;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY:
>>>> @@ -1060,6 +1096,204 @@ static void v4l_sanitize_format(struct v4l2_format *fmt)
>>>>              sizeof(fmt->fmt.pix) - offset);
>>>>   }
>>>> +static void
>>>> +v4l2_ext_pix_format_to_pix_format(const struct v4l2_ext_pix_format *ef,
>>>> +                  struct v4l2_pix_format *pix)
>>>> +{
>>>> +    unsigned int i;
>>>> +
>>>> +    pix->width = ef->width;
>>>> +    pix->height = ef->height;
>>>> +    pix->field = ef->field;
>>>> +    pix->flags = V4L2_PIX_FMT_FLAG_SET_CSC;
>>>> +    pix->colorspace = ef->colorspace;
>>>> +    pix->ycbcr_enc = ef->ycbcr_enc;
>>>> +    pix->priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>> +    pix->quantization = ef->quantization;
>>>> +    pix->pixelformat = ef->pixelformat;
>>>> +    pix->bytesperline = ef->plane_fmt[0].bytesperline;
>>>> +    pix->sizeimage = ef->plane_fmt[0].sizeimage;
>>>> +    for (i = 1; i < VIDEO_MAX_PLANES && ef->plane_fmt[i].sizeimage; i++)
>>>> +        pix->sizeimage += ef->plane_fmt[i].sizeimage;
>>>> +}
>>>> +
>>>> +static void
>>>> +v4l2_ext_pix_format_to_pix_mp_format(const struct v4l2_ext_pix_format *ef,
>>>> +                     struct v4l2_pix_format_mplane *pix_mp)
>>>> +{
>>>> +    const struct v4l2_format_info *info =
>>>> +                    v4l2_format_info(ef->pixelformat);
>>>> +    unsigned int i;
>>>> +
>>>> +    pix_mp->width = ef->width;
>>>> +    pix_mp->height = ef->height;
>>>> +    pix_mp->field = ef->field;
>>>> +    pix_mp->flags = V4L2_PIX_FMT_FLAG_SET_CSC;
>>>> +    pix_mp->colorspace = ef->colorspace;
>>>> +    pix_mp->ycbcr_enc = ef->ycbcr_enc;
>>>> +    pix_mp->quantization = ef->quantization;
>>>> +    pix_mp->pixelformat = ef->pixelformat;
>>>> +
>>>> +    /* This is true when converting to non-M-variant */
>>>> +    if (info && info->mem_planes == 1) {
>>>> +        pix_mp->plane_fmt[0] = ef->plane_fmt[0];
>>>> +        pix_mp->num_planes = 1;
>>>> +        for (i = 1; i < VIDEO_MAX_PLANES && ef->plane_fmt[i].sizeimage; i++)
>>>> +            pix_mp->plane_fmt[0].sizeimage += ef->plane_fmt[i].sizeimage;
>>>> +
>>>> +        return;
>>>> +    }
>>>> +
>>>> +    for (i = 0; i < VIDEO_MAX_PLANES && ef->plane_fmt[i].sizeimage; i++)
>>>> +        pix_mp->plane_fmt[i] = ef->plane_fmt[i];
>>>> +    pix_mp->num_planes = i;
>>>> +}
>>>> +
>>>> +/*
>>>> + * v4l2_ext_pix_format_to_format - convert to v4l2_ext_pix_format to v4l2_format
>>>> + *
>>>> + * @ef: A pointer to struct struct v4l2_ext_pix_format to be converted.
>>>> + * @f: A pointer to struct v4l2_format to be filled.
>>>> + * @is_mplane: Bool indicating if multiplanar API should be used in @f.
>>>> + *
>>>> + * If pixelformat should be converted to M-variant, change ef->pixelformat
>>>> + * to the M-variant before calling this function.
>>>> + */
>>>> +static void v4l2_ext_pix_format_to_format(const struct v4l2_ext_pix_format *ef,
>>>> +                      struct v4l2_format *f, bool is_mplane)
>>>> +{
>>>> +    memset(f, 0, sizeof(*f));
>>>> +
>>>> +    if (ef->modifier != DRM_FORMAT_MOD_LINEAR &&
>>>> +        ef->modifier != DRM_FORMAT_MOD_INVALID)
>>>> +        pr_warn("Modifiers are not supported in v4l2_format, ignoring %llx\n",
>>>> +            ef->modifier);
>>>> +
>>>> +    if (!is_mplane) {
>>>> +        f->type = ef->type;
>>>> +        v4l2_ext_pix_format_to_pix_format(ef, &f->fmt.pix);
>>>> +        return;
>>>> +    }
>>>> +
>>>> +    if (ef->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
>>>> +        f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
>>>> +    else
>>>> +        f->type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
>>>> +
>>>> +    v4l2_ext_pix_format_to_pix_mp_format(ef, &f->fmt.pix_mp);
>>>> +}
>>>> +
>>>> +static void
>>>> +v4l2_pix_format_to_ext_pix_format(const struct v4l2_pix_format *pix,
>>>> +                  struct v4l2_ext_pix_format *ef)
>>>> +{
>>>> +    const struct v4l2_format_info *info =
>>>> +                    v4l2_format_info(pix->pixelformat);
>>>> +    unsigned int i;
>>>> +
>>>> +    ef->width = pix->width;
>>>> +    ef->height = pix->height;
>>>> +    ef->field = pix->field;
>>>> +    ef->colorspace = pix->colorspace;
>>>> +    ef->ycbcr_enc = pix->ycbcr_enc;
>>>> +    ef->quantization = pix->quantization;
>>>> +    ef->xfer_func = pix->xfer_func;
>>>> +    if (pix->flags)
>>>> +        pr_warn("Ignoring pixelformat flags 0x%x\n", pix->flags);
>>>> +
>>>> +    /* We assume M-variants won't be used in this function */
>>>> +    ef->pixelformat = pix->pixelformat;
>>>> +
>>>> +    ef->plane_fmt[0].bytesperline = pix->bytesperline;
>>>> +    ef->plane_fmt[0].sizeimage = pix->sizeimage;
>>>> +
>>>> +    if (!info)
>>>> +        return;
>>>> +
>>>> +    for (i = 1; i < info->comp_planes; i++) {
>>>> +        ef->plane_fmt[i].bytesperline = pix->bytesperline / info->hdiv;
>>>> +        ef->plane_fmt[i].sizeimage = ef->plane_fmt[i].bytesperline *
>>>> +                         ef->height / info->vdiv;
>>>> +        ef->plane_fmt[0].sizeimage -= ef->plane_fmt[i].sizeimage;
>>>> +    }
>>>> +}
>>>> +
>>>> +static void
>>>> +v4l2_pix_mp_format_to_ext_pix_format(const struct v4l2_pix_format_mplane *pix_mp,
>>>> +                     struct v4l2_ext_pix_format *ef)
>>>> +{
>>>> +    const struct v4l2_format_info *info =
>>>> +                    v4l2_format_info(pix_mp->pixelformat);
>>>> +    unsigned int i;
>>>> +
>>>> +    ef->width = pix_mp->width;
>>>> +    ef->height = pix_mp->height;
>>>> +    ef->field = pix_mp->field;
>>>> +    ef->colorspace = pix_mp->colorspace;
>>>> +    ef->ycbcr_enc = pix_mp->ycbcr_enc;
>>>> +    ef->quantization = pix_mp->quantization;
>>>> +    ef->xfer_func = pix_mp->xfer_func;
>>>> +    if (pix_mp->flags)
>>>> +        pr_warn("Ignoring pixelformat flags 0x%x\n", pix_mp->flags);
>>>> +
>>>> +    if (!info)
>>>> +        return;
>>>> +
>>>> +    ef->pixelformat = info && info->norm ?
>>>
>>> 'info &&' can be dropped, info is always non-NULL here.
>>>
>>>> +              info->norm : pix_mp->pixelformat;
>>>> +
>>>> +    if (info->comp_planes == info->mem_planes) {
>>>> +        for (i = 0; i < pix_mp->num_planes && i < VIDEO_MAX_PLANES; i++)
>>>> +            ef->plane_fmt[i] = pix_mp->plane_fmt[i];
>>>> +
>>>> +        return;
>>>> +    }
>>>> +
>>>> +    /* case where mem_planes is 1 and comp_planes > 1 */
>>>> +    ef->plane_fmt[0] = pix_mp->plane_fmt[0];
>>>> +    for (i = 1; i < info->comp_planes; i++) {
>>>> +        ef->plane_fmt[i].bytesperline =
>>>> +            pix_mp->plane_fmt[0].bytesperline / info->hdiv;
>>>> +        ef->plane_fmt[i].sizeimage =
>>>> +            ef->plane_fmt[i].bytesperline * ef->height / info->vdiv;
>>>> +        ef->plane_fmt[0].sizeimage -= ef->plane_fmt[i].sizeimage;
>>>> +    }
>>>> +}
>>>> +
>>>> +/*
>>>> + * v4l2_format_to_ext_pix_format - convert to v4l2_format to v4l2_ext_pix_format
>>>> + *
>>>> + * @f: A pointer to struct v4l2_format to be converted.
>>>> + * @ef: A pointer to struct struct v4l2_ext_pix_format to be filled.
>>>> + *
>>>> + * This method normalize the pixelformat to non-M variant.
>>>> + */
>>>> +static void v4l2_format_to_ext_pix_format(const struct v4l2_format *f,
>>>> +                      struct v4l2_ext_pix_format *ef)
>>>> +{
>>>> +    memset(ef, 0, sizeof(*ef));
>>>> +
>>>> +    switch (f->type) {
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> +        ef->type = f->type;
>>>> +        v4l2_pix_format_to_ext_pix_format(&f->fmt.pix, ef);
>>>> +        break;
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>> +        ef->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
>>>> +        v4l2_pix_mp_format_to_ext_pix_format(&f->fmt.pix_mp, ef);
>>>> +        break;
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>>>> +        ef->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
>>>> +        v4l2_pix_mp_format_to_ext_pix_format(&f->fmt.pix_mp, ef);
>>>> +        break;
>>>> +    default:
>>>> +        WARN("Converting to Ext Pix Format with wrong buffer type %s\n",
>>>> +             prt_names(f->type, v4l2_type_names));
>>>> +        break;
>>>> +    }
>>>> +}
>>>> +
>>>>   static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
>>>>                   struct file *file, void *fh, void *arg)
>>>>   {
>>>> @@ -1565,6 +1799,100 @@ static void v4l_pix_format_touch(struct v4l2_pix_format *p)
>>>>       p->xfer_func = 0;
>>>>   }
>>>> +static int v4l_fmt_ioctl_via_ext(const struct v4l2_ioctl_ops *ops,
>>>> +                 struct file *file, void *fh,
>>>> +                 struct v4l2_format *f,
>>>> +                 unsigned int ioctl)
>>>> +{
>>>> +    bool is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(f->type);
>>>> +    struct video_device *vdev = video_devdata(file);
>>>> +    struct v4l2_ext_pix_format ef = {0};
>>>> +    u32 original_pixfmt = 0;
>>>> +    u32 cap_mask;
>>>> +    int ret;
>>>> +
>>>> +    if (ioctl != VIDIOC_G_FMT) {
>>>> +        /*
>>>> +         * If CSC attributes are read only, set them to DEFAULT
>>>> +         * to avoid changes by the driver.
>>>> +         */
>>>> +        if (is_multiplanar) {
>>>> +            if (!(f->fmt.pix_mp.flags & V4L2_PIX_FMT_FLAG_SET_CSC)) {
>>>> +                f->fmt.pix_mp.colorspace = V4L2_COLORSPACE_DEFAULT;
>>>> +                f->fmt.pix_mp.ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
>>>> +                f->fmt.pix_mp.quantization = V4L2_QUANTIZATION_DEFAULT;
>>>> +                f->fmt.pix_mp.xfer_func = V4L2_XFER_FUNC_DEFAULT;
>>>> +            }
>>>> +            /* Unset the flag to avoid warning in the convertion */
>>>> +            f->fmt.pix_mp.flags &= ~V4L2_PIX_FMT_FLAG_SET_CSC;
>>>> +
>>>> +            /* Save pixelformat in case M-variant is being used */
>>>> +            original_pixfmt = f->fmt.pix_mp.pixelformat;
>>>> +        } else {
>>>> +            if (!(f->fmt.pix.flags & V4L2_PIX_FMT_FLAG_SET_CSC)) {
>>>> +                f->fmt.pix.colorspace = V4L2_COLORSPACE_DEFAULT;
>>>> +                f->fmt.pix.ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
>>>> +                f->fmt.pix.quantization = V4L2_QUANTIZATION_DEFAULT;
>>>> +                f->fmt.pix.xfer_func = V4L2_XFER_FUNC_DEFAULT;
>>>> +            }
>>>> +            /* Unset the flag to avoid warning in the convertion */
>>>> +            f->fmt.pix.flags &= ~V4L2_PIX_FMT_FLAG_SET_CSC;
>>>> +        }
>>>> +        v4l2_format_to_ext_pix_format(f, &ef);
>>>> +    }
>>>> +
>>>> +    switch (f->type) {
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>> +        cap_mask = V4L2_CAP_VIDEO_CAPTURE_MPLANE |
>>>> +               V4L2_CAP_VIDEO_M2M_MPLANE;
>>>> +        if (!!(vdev->device_caps & cap_mask) !=
>>>> +            (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE))
>>>> +            return -EINVAL;
>>>> +
>>>> +        ef.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
>>>> +        if (ioctl == VIDIOC_G_FMT)
>>>> +            ret = ops->vidioc_g_ext_pix_fmt_vid_cap(file, fh, &ef);
>>>> +        else if (ioctl == VIDIOC_S_FMT)
>>>> +            ret = ops->vidioc_s_ext_pix_fmt_vid_cap(file, fh, &ef);
>>>> +        else
>>>> +            ret = ops->vidioc_try_ext_pix_fmt_vid_cap(file, fh,
>>>> +                                  &ef);
>>>> +        break;
>>>> +
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>>>> +        cap_mask = V4L2_CAP_VIDEO_OUTPUT_MPLANE |
>>>> +               V4L2_CAP_VIDEO_M2M_MPLANE;
>>>> +        if (!!(vdev->device_caps & cap_mask) !=
>>>> +            (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE))
>>>> +            return -EINVAL;
>>>> +
>>>> +        ef.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
>>>> +        if (ioctl == VIDIOC_G_FMT)
>>>> +            ret = ops->vidioc_g_ext_pix_fmt_vid_out(file, fh, &ef);
>>>> +        else if (ioctl == VIDIOC_S_FMT)
>>>> +            ret = ops->vidioc_s_ext_pix_fmt_vid_out(file, fh, &ef);
>>>> +        else
>>>> +            ret = ops->vidioc_try_ext_pix_fmt_vid_out(file, fh,
>>>> +                                  &ef);
>>>> +        break;
>>>> +
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    if (original_pixfmt != ef.pixelformat &&
>>>> +        v4l2_format_info(original_pixfmt))
>>>
>>> Could this test be simplified to: 'if (original_pixfmt)'?
>>>
>>> I.e., if the original pixfmt was saved, then restore it here.
>>>
>>>> +        ef.pixelformat = original_pixfmt;
>>>> +
>>>> +    v4l2_ext_pix_format_to_format(&ef, f, is_multiplanar);
>>>> +    return 0;
>>>> +}
>>>> +
>>>>   static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
>>>>                   struct file *file, void *fh, void *arg)
>>>>   {
>>>> @@ -1601,17 +1929,26 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
>>>>       switch (p->type) {
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> -        if (unlikely(!ops->vidioc_g_fmt_vid_cap))
>>>> +        if (unlikely(!ops->vidioc_g_fmt_vid_cap &&
>>>> +                 !ops->vidioc_g_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>> -        ret = ops->vidioc_g_fmt_vid_cap(file, fh, arg);
>>>> +        ret = ops->vidioc_g_fmt_vid_cap ?
>>>> +              ops->vidioc_g_fmt_vid_cap(file, fh, arg) :
>>>> +              v4l_fmt_ioctl_via_ext(ops, file, fh, arg,
>>>> +                        VIDIOC_G_FMT);
>>>>           /* just in case the driver zeroed it again */
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>>           if (vfd->vfl_type == VFL_TYPE_TOUCH)
>>>>               v4l_pix_format_touch(&p->fmt.pix);
>>>>           return ret;
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>> -        return ops->vidioc_g_fmt_vid_cap_mplane(file, fh, arg);
>>>> +        if (ops->vidioc_g_fmt_vid_cap_mplane)
>>>> +            return ops->vidioc_g_fmt_vid_cap_mplane(file, fh, arg);
>>>> +        else if (ops->vidioc_g_ext_pix_fmt_vid_cap)
>>>
>>> 'else' can be dropped.
>>>
>>>> +            return v4l_fmt_ioctl_via_ext(ops, file, fh, arg,
>>>> +                             VIDIOC_G_FMT);
>>>> +        break;
>>>>       case V4L2_BUF_TYPE_VIDEO_OVERLAY:
>>>>           return ops->vidioc_g_fmt_vid_overlay(file, fh, arg);
>>>>       case V4L2_BUF_TYPE_VBI_CAPTURE:
>>>> @@ -1619,15 +1956,23 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
>>>> ��     case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE:
>>>>           return ops->vidioc_g_fmt_sliced_vbi_cap(file, fh, arg);
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> -        if (unlikely(!ops->vidioc_g_fmt_vid_out))
>>>> +        if (unlikely(!ops->vidioc_g_fmt_vid_out &&
>>>> +                 !ops->vidioc_g_ext_pix_fmt_vid_out))
>>>>               break;
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>> -        ret = ops->vidioc_g_fmt_vid_out(file, fh, arg);
>>>> +        ret = ops->vidioc_g_fmt_vid_out ?
>>>> +              ops->vidioc_g_fmt_vid_out(file, fh, arg) :
>>>> +              v4l_fmt_ioctl_via_ext(ops, file, fh, arg, VIDIOC_G_FMT);
>>>>           /* just in case the driver zeroed it again */
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>>           return ret;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>>>> -        return ops->vidioc_g_fmt_vid_out_mplane(file, fh, arg);
>>>> +        if (ops->vidioc_g_fmt_vid_out_mplane)
>>>> +            return ops->vidioc_g_fmt_vid_out_mplane(file, fh, arg);
>>>> +        else if (ops->vidioc_g_ext_pix_fmt_vid_out)
>>>
>>> Ditto.
>>>
>>>> +            return v4l_fmt_ioctl_via_ext(ops, file, fh, arg,
>>>> +                             VIDIOC_G_FMT);
>>>> +        break;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY:
>>>>           return ops->vidioc_g_fmt_vid_out_overlay(file, fh, arg);
>>>>       case V4L2_BUF_TYPE_VBI_OUTPUT:
>>>> @@ -1646,6 +1991,42 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
>>>>       return -EINVAL;
>>>>   }
>>>> +static int v4l_g_ext_pix_fmt(const struct v4l2_ioctl_ops *ops,
>>>> +                 struct file *file, void *fh, void *arg)
>>>> +{
>>>> +    struct v4l2_ext_pix_format *ef = arg;
>>>> +    struct v4l2_format f = {
>>>> +        .type = ef->type,
>>>> +    };
>>>> +    int ret = check_fmt(file, ef->type);
>>>> +
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    memset(ef, 0, sizeof(*ef));
>>>> +    ef->type = f.type;
>>>> +
>>>> +    switch (f.type) {
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> +        if (ops->vidioc_g_ext_pix_fmt_vid_cap)
>>>> +            return ops->vidioc_g_ext_pix_fmt_vid_cap(file, fh, ef);
>>>> +        break;
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> +        if (ops->vidioc_g_ext_pix_fmt_vid_out)
>>>> +            return ops->vidioc_g_ext_pix_fmt_vid_out(file, fh, ef);
>>>> +        break;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    ret = v4l_g_fmt(ops, file, fh, &f);
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    v4l2_format_to_ext_pix_format(&f, ef);
>>>> +    return 0;
>>>> +}
>>>> +
>>>>   static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
>>>>                   struct file *file, void *fh, void *arg)
>>>>   {
>>>> @@ -1664,23 +2045,29 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
>>>>       switch (p->type) {
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> -        if (unlikely(!ops->vidioc_s_fmt_vid_cap))
>>>> +        if (unlikely(!ops->vidioc_s_fmt_vid_cap &&
>>>> +                 !ops->vidioc_s_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix);
>>>> -        ret = ops->vidioc_s_fmt_vid_cap(file, fh, arg);
>>>> +        ret = ops->vidioc_s_fmt_vid_cap ?
>>>> +              ops->vidioc_s_fmt_vid_cap(file, fh, arg) :
>>>> +              v4l_fmt_ioctl_via_ext(ops, file, fh, arg, VIDIOC_S_FMT);
>>>>           /* just in case the driver zeroed it again */
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>>           if (vfd->vfl_type == VFL_TYPE_TOUCH)
>>>>               v4l_pix_format_touch(&p->fmt.pix);
>>>>           return ret;
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>> -        if (unlikely(!ops->vidioc_s_fmt_vid_cap_mplane))
>>>> +        if (unlikely(!ops->vidioc_s_fmt_vid_cap_mplane &&
>>>> +                 !ops->vidioc_s_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
>>>>           for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
>>>>               CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
>>>>                         bytesperline);
>>>> -        return ops->vidioc_s_fmt_vid_cap_mplane(file, fh, arg);
>>>> +        return ops->vidioc_s_fmt_vid_cap_mplane ?
>>>> +               ops->vidioc_s_fmt_vid_cap_mplane(file, fh, arg) :
>>>> +               v4l_fmt_ioctl_via_ext(ops, file, fh, arg,  VIDIOC_S_FMT);
>>>>       case V4L2_BUF_TYPE_VIDEO_OVERLAY:
>>>>           if (unlikely(!ops->vidioc_s_fmt_vid_overlay))
>>>>               break;
>>>> @@ -1697,21 +2084,27 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
>>>>           CLEAR_AFTER_FIELD(p, fmt.sliced.io_size);
>>>>           return ops->vidioc_s_fmt_sliced_vbi_cap(file, fh, arg);
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> -        if (unlikely(!ops->vidioc_s_fmt_vid_out))
>>>> +        if (unlikely(!ops->vidioc_s_fmt_vid_out &&
>>>> +                 !ops->vidioc_s_ext_pix_fmt_vid_out))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix);
>>>> -        ret = ops->vidioc_s_fmt_vid_out(file, fh, arg);
>>>> +        ret = ops->vidioc_s_fmt_vid_out ?
>>>> +              ops->vidioc_s_fmt_vid_out(file, fh, arg) :
>>>> +              v4l_fmt_ioctl_via_ext(ops, file, fh, arg, VIDIOC_S_FMT);
>>>>           /* just in case the driver zeroed it again */
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>>           return ret;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>>>> -        if (unlikely(!ops->vidioc_s_fmt_vid_out_mplane))
>>>> +        if (unlikely(!ops->vidioc_s_fmt_vid_out_mplane &&
>>>> +                 !ops->vidioc_s_ext_pix_fmt_vid_out))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
>>>>           for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
>>>>               CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
>>>>                         bytesperline);
>>>> -        return ops->vidioc_s_fmt_vid_out_mplane(file, fh, arg);
>>>> +        return ops->vidioc_s_fmt_vid_out_mplane ?
>>>> +               ops->vidioc_s_fmt_vid_out_mplane(file, fh, arg) :
>>>> +               v4l_fmt_ioctl_via_ext(ops, file, fh, arg, VIDIOC_S_FMT);
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY:
>>>>           if (unlikely(!ops->vidioc_s_fmt_vid_out_overlay))
>>>>               break;
>>>> @@ -1751,6 +2144,43 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
>>>>       return -EINVAL;
>>>>   }
>>>> +static int v4l_s_ext_pix_fmt(const struct v4l2_ioctl_ops *ops,
>>>> +                 struct file *file, void *fh, void *arg)
>>>> +{
>>>> +    struct video_device *vfd = video_devdata(file);
>>>> +    struct v4l2_ext_pix_format *ef = arg;
>>>> +    struct v4l2_format f;
>>>> +    int ret = check_fmt(file, ef->type);
>>>> +
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    memset(ef->reserved, 0, sizeof(ef->reserved));
>>>> +
>>>> +    switch (ef->type) {
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> +        if (ops->vidioc_s_ext_pix_fmt_vid_cap)
>>>> +            return ops->vidioc_s_ext_pix_fmt_vid_cap(file, fh, ef);
>>>> +        break;
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> +        if (ops->vidioc_s_ext_pix_fmt_vid_out)
>>>> +            return ops->vidioc_s_ext_pix_fmt_vid_out(file, fh, ef);
>>>> +        break;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    v4l2_ext_pix_format_to_format(ef, &f, V4L2_IS_CAP_MULTIPLANAR(vfd));
>>>> +
>>>> +    ret = v4l_s_fmt(ops, file, fh, &f);
>>>> +    if (ret)
>>>> +        /* TODO: retry with M-variant of ef->pixelformat? */
>>>
>>> See my comments on this at the top.
>>>
>>>> +        return ret;
>>>> +
>>>> +    v4l2_format_to_ext_pix_format(&f, ef);
>>>> +    return 0;
>>>> +}
>>>> +
>>>>   static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
>>>>                   struct file *file, void *fh, void *arg)
>>>>   {
>>>> @@ -1766,23 +2196,30 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
>>>>       switch (p->type) {
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> -        if (unlikely(!ops->vidioc_try_fmt_vid_cap))
>>>> +        if (unlikely(!ops->vidioc_try_fmt_vid_cap &&
>>>> +                 !ops->vidioc_try_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix);
>>>> -        ret = ops->vidioc_try_fmt_vid_cap(file, fh, arg);
>>>> +        ret = ops->vidioc_try_fmt_vid_cap ?
>>>> +              ops->vidioc_try_fmt_vid_cap(file, fh, arg) :
>>>> +              v4l_fmt_ioctl_via_ext(ops, file, fh, arg, VIDIOC_TRY_FMT);
>>>>           /* just in case the driver zeroed it again */
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>>           if (vfd->vfl_type == VFL_TYPE_TOUCH)
>>>>               v4l_pix_format_touch(&p->fmt.pix);
>>>>           return ret;
>>>>       case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>> -        if (unlikely(!ops->vidioc_try_fmt_vid_cap_mplane))
>>>> +        if (unlikely(!ops->vidioc_try_fmt_vid_cap_mplane &&
>>>> +                 !ops->vidioc_try_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
>>>>           for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
>>>>               CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
>>>>                         bytesperline);
>>>> -        return ops->vidioc_try_fmt_vid_cap_mplane(file, fh, arg);
>>>> +        return ops->vidioc_try_fmt_vid_cap_mplane ?
>>>> +               ops->vidioc_try_fmt_vid_cap_mplane(file, fh, arg) :
>>>> +               v4l_fmt_ioctl_via_ext(ops, file, fh, arg,
>>>> +                         VIDIOC_TRY_FMT);
>>>>       case V4L2_BUF_TYPE_VIDEO_OVERLAY:
>>>>           if (unlikely(!ops->vidioc_try_fmt_vid_overlay))
>>>>               break;
>>>> @@ -1799,21 +2236,28 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
>>>>           CLEAR_AFTER_FIELD(p, fmt.sliced.io_size);
>>>>           return ops->vidioc_try_fmt_sliced_vbi_cap(file, fh, arg);
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> -        if (unlikely(!ops->vidioc_try_fmt_vid_out))
>>>> +        if (unlikely(!ops->vidioc_try_fmt_vid_out &&
>>>> +                 !ops->vidioc_try_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix);
>>>> -        ret = ops->vidioc_try_fmt_vid_out(file, fh, arg);
>>>> +        ret = ops->vidioc_try_fmt_vid_out ?
>>>> +              ops->vidioc_try_fmt_vid_out(file, fh, arg) :
>>>> +              v4l_fmt_ioctl_via_ext(ops, file, fh, arg, VIDIOC_TRY_FMT);
>>>>           /* just in case the driver zeroed it again */
>>>>           p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
>>>>           return ret;
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>>>> -        if (unlikely(!ops->vidioc_try_fmt_vid_out_mplane))
>>>> +        if (unlikely(!ops->vidioc_try_fmt_vid_out_mplane &&
>>>> +                 !ops->vidioc_try_ext_pix_fmt_vid_cap))
>>>>               break;
>>>>           CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
>>>>           for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
>>>>               CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
>>>>                         bytesperline);
>>>> -        return ops->vidioc_try_fmt_vid_out_mplane(file, fh, arg);
>>>> +        return ops->vidioc_try_fmt_vid_out_mplane ?
>>>> +               ops->vidioc_try_fmt_vid_out_mplane(file, fh, arg) :
>>>> +               v4l_fmt_ioctl_via_ext(ops, file, fh, arg,
>>>> +                         VIDIOC_TRY_FMT);
>>>>       case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY:
>>>>           if (unlikely(!ops->vidioc_try_fmt_vid_out_overlay))
>>>>               break;
>>>> @@ -1853,6 +2297,45 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
>>>>       return -EINVAL;
>>>>   }
>>>> +static int v4l_try_ext_pix_fmt(const struct v4l2_ioctl_ops *ops,
>>>> +                   struct file *file, void *fh, void *arg)
>>>> +{
>>>> +    struct video_device *vfd = video_devdata(file);
>>>> +    struct v4l2_ext_pix_format *ef = arg;
>>>> +    struct v4l2_format f;
>>>> +    int ret = check_fmt(file, ef->type);
>>>> +
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    memset(ef->reserved, 0, sizeof(ef->reserved));
>>>> +
>>>> +    switch (ef->type) {
>>>> +    case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>>>> +        if (ops->vidioc_try_ext_pix_fmt_vid_cap)
>>>> +            return ops->vidioc_try_ext_pix_fmt_vid_cap(file, fh,
>>>> +                                   ef);
>>>> +        break;
>>>> +    case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>>>> +        if (ops->vidioc_try_ext_pix_fmt_vid_out)
>>>> +            return ops->vidioc_try_ext_pix_fmt_vid_out(file, fh,
>>>> +                                   ef);
>>>> +        break;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    v4l2_ext_pix_format_to_format(ef, &f, V4L2_IS_CAP_MULTIPLANAR(vfd));
>>>> +
>>>> +    ret = v4l_try_fmt(ops, file, fh, &f);
>>>> +    if (ret)
>>>> +        /* TODO: retry with M-variant of ef->pixelformat? */
>>>> +        return ret;
>>>> +
>>>> +    v4l2_format_to_ext_pix_format(&f, ef);
>>>> +    return 0;
>>>> +}
>>>> +
>>>>   static int v4l_streamon(const struct v4l2_ioctl_ops *ops,
>>>>                   struct file *file, void *fh, void *arg)
>>>>   {
>>>> @@ -2854,6 +3337,9 @@ static const struct v4l2_ioctl_info v4l2_ioctls[] = {
>>>>       IOCTL_INFO(VIDIOC_ENUM_FREQ_BANDS, v4l_enum_freq_bands, v4l_print_freq_band, 0),
>>>>       IOCTL_INFO(VIDIOC_DBG_G_CHIP_INFO, v4l_dbg_g_chip_info, v4l_print_dbg_chip_info, INFO_FL_CLEAR(v4l2_dbg_chip_info, match)),
>>>>       IOCTL_INFO(VIDIOC_QUERY_EXT_CTRL, v4l_query_ext_ctrl, v4l_print_query_ext_ctrl, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_query_ext_ctrl, id)),
>>>> +    IOCTL_INFO(VIDIOC_G_EXT_PIX_FMT, v4l_g_ext_pix_fmt, v4l_print_ext_pix_format, 0),
>>>> +    IOCTL_INFO(VIDIOC_S_EXT_PIX_FMT, v4l_s_ext_pix_fmt, v4l_print_ext_pix_format, INFO_FL_PRIO),
>>>> +    IOCTL_INFO(VIDIOC_TRY_EXT_PIX_FMT, v4l_try_ext_pix_fmt, v4l_print_ext_pix_format, 0),
>>>>   };
>>>>   #define V4L2_IOCTLS ARRAY_SIZE(v4l2_ioctls)
>>>> diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
>>>> index edb733f21604..c44708dc9355 100644
>>>> --- a/include/media/v4l2-ioctl.h
>>>> +++ b/include/media/v4l2-ioctl.h
>>>> @@ -48,11 +48,17 @@ struct v4l2_fh;
>>>>    * @vidioc_g_fmt_vid_cap: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video capture
>>>>    *    in single plane mode
>>>> + * @vidioc_g_ext_pix_fmt_vid_cap: pointer to the function that implements
>>>> + *    :ref:`VIDIOC_G_EXT_PIX_FMT <vidioc_g_ext_pix_fmt>` ioctl logic for video
>>>> + *    capture
>>>>    * @vidioc_g_fmt_vid_overlay: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video overlay
>>>>    * @vidioc_g_fmt_vid_out: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video out
>>>>    *    in single plane mode
>>>> + * @vidioc_g_ext_pix_fmt_vid_out: pointer to the function that implements
>>>> + *    :ref:`VIDIOC_G_EXT_PIX_FMT <vidioc_g_ext_pix_fmt>` ioctl logic for video
>>>> + *    out
>>>>    * @vidioc_g_fmt_vid_out_overlay: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video overlay output
>>>>    * @vidioc_g_fmt_vbi_cap: pointer to the function that implements
>>>> @@ -82,11 +88,16 @@ struct v4l2_fh;
>>>>    * @vidioc_s_fmt_vid_cap: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video capture
>>>>    *    in single plane mode
>>>> + * @vidioc_s_ext_pix_fmt_vid_cap: pointer to the function that implements
>>>> + *    :ref:`VIDIOC_S_EXT_PIX_FMT <vidioc_g_ext_pix_fmt>` ioctl logic for video
>>>> + *    capture
>>>>    * @vidioc_s_fmt_vid_overlay: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video overlay
>>>>    * @vidioc_s_fmt_vid_out: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video out
>>>>    *    in single plane mode
>>>> + * @vidioc_s_ext_pix_fmt_vid_out: pointer to the function that implements
>>>> + *    :ref:`VIDIOC_S_EXT_PIX_FMT <vidioc_g_fmt>` ioctl logic for video out
>>>>    * @vidioc_s_fmt_vid_out_overlay: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video overlay output
>>>>    * @vidioc_s_fmt_vbi_cap: pointer to the function that implements
>>>> @@ -116,11 +127,16 @@ struct v4l2_fh;
>>>>    * @vidioc_try_fmt_vid_cap: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video capture
>>>>    *    in single plane mode
>>>> + * @vidioc_try_ext_pix_fmt_vid_cap: pointer to the function that implements
>>>> + *    :ref:`VIDIOC_TRY_EXT_PIX_FMT <vidioc_g_ext_pix_fmt>` ioctl logic for
>>>> +    video capture
>>>>    * @vidioc_try_fmt_vid_overlay: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video overlay
>>>>    * @vidioc_try_fmt_vid_out: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video out
>>>>    *    in single plane mode
>>>> + * @vidioc_try_ext_pix_fmt_vid_out: pointer to the function that implements
>>>> + *    :ref:`VIDIOC_TRY_EXT_PIX_FMT <vidioc_g_fmt>` ioctl logic for video out
>>>>    * @vidioc_try_fmt_vid_out_overlay: pointer to the function that implements
>>>>    *    :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video overlay
>>>>    *    output
>>>> @@ -319,10 +335,14 @@ struct v4l2_ioctl_ops {
>>>>       /* VIDIOC_G_FMT handlers */
>>>>       int (*vidioc_g_fmt_vid_cap)(struct file *file, void *fh,
>>>>                       struct v4l2_format *f);
>>>> +    int (*vidioc_g_ext_pix_fmt_vid_cap)(struct file *file, void *fh,
>>>> +                        struct v4l2_ext_pix_format *ef);
>>>>       int (*vidioc_g_fmt_vid_overlay)(struct file *file, void *fh,
>>>>                       struct v4l2_format *f);
>>>>       int (*vidioc_g_fmt_vid_out)(struct file *file, void *fh,
>>>>                       struct v4l2_format *f);
>>>> +    int (*vidioc_g_ext_pix_fmt_vid_out)(struct file *file, void *fh,
>>>> +                        struct v4l2_ext_pix_format *ef);
>>>>       int (*vidioc_g_fmt_vid_out_overlay)(struct file *file, void *fh,
>>>>                           struct v4l2_format *f);
>>>>       int (*vidioc_g_fmt_vbi_cap)(struct file *file, void *fh,
>>>> @@ -349,10 +369,14 @@ struct v4l2_ioctl_ops {
>>>>       /* VIDIOC_S_FMT handlers */
>>>>       int (*vidioc_s_fmt_vid_cap)(struct file *file, void *fh,
>>>>                       struct v4l2_format *f);
>>>> +    int (*vidioc_s_ext_pix_fmt_vid_cap)(struct file *file, void *fh,
>>>> +                        struct v4l2_ext_pix_format *ef);
>>>>       int (*vidioc_s_fmt_vid_overlay)(struct file *file, void *fh,
>>>>                       struct v4l2_format *f);
>>>>       int (*vidioc_s_fmt_vid_out)(struct file *file, void *fh,
>>>>                       struct v4l2_format *f);
>>>> +    int (*vidioc_s_ext_pix_fmt_vid_out)(struct file *file, void *fh,
>>>> +                        struct v4l2_ext_pix_format *ef);
>>>>       int (*vidioc_s_fmt_vid_out_overlay)(struct file *file, void *fh,
>>>>                           struct v4l2_format *f);
>>>>       int (*vidioc_s_fmt_vbi_cap)(struct file *file, void *fh,
>>>> @@ -379,10 +403,14 @@ struct v4l2_ioctl_ops {
>>>>       /* VIDIOC_TRY_FMT handlers */
>>>>       int (*vidioc_try_fmt_vid_cap)(struct file *file, void *fh,
>>>>                         struct v4l2_format *f);
>>>> +    int (*vidioc_try_ext_pix_fmt_vid_cap)(struct file *file, void *fh,
>>>> +                          struct v4l2_ext_pix_format *ef);
>>>>       int (*vidioc_try_fmt_vid_overlay)(struct file *file, void *fh,
>>>>                         struct v4l2_format *f);
>>>>       int (*vidioc_try_fmt_vid_out)(struct file *file, void *fh,
>>>>                         struct v4l2_format *f);
>>>> +    int (*vidioc_try_ext_pix_fmt_vid_out)(struct file *file, void *fh,
>>>> +                          struct v4l2_ext_pix_format *ef);
>>>>       int (*vidioc_try_fmt_vid_out_overlay)(struct file *file, void *fh,
>>>>                            struct v4l2_format *f);
>>>>       int (*vidioc_try_fmt_vbi_cap)(struct file *file, void *fh,
>>>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>>>> index d9b7c9177605..a2d850513708 100644
>>>> --- a/include/uapi/linux/videodev2.h
>>>> +++ b/include/uapi/linux/videodev2.h
>>>> @@ -2270,6 +2270,43 @@ struct v4l2_pix_format_mplane {
>>>>       __u8                reserved[7];
>>>>   } __attribute__ ((packed));
>>>> +/**
>>>> + * struct v4l2_ext_pix_format - extended single/multiplanar format definition
>>>> + * @type:        type of the data stream; V4L2_BUF_TYPE_VIDEO_CAPTURE or
>>>> + *            V4L2_BUF_TYPE_VIDEO_OUTPUT
>>>> + * @width:        image width in pixels
>>>> + * @height:        image height in pixels
>>>> + * @field:        enum v4l2_field; field order (for interlaced video)
>>>> + * @plane_fmt:        per-plane information
>>>> + * @pixelformat:    little endian four character code (fourcc)
>>>> + * @modifier:        modifier applied to the format (used for tiled formats
>>>> + *            and other kind of HW-specific formats, like compressed
>>>> + *            formats) as defined in drm_fourcc.h
>>>> + * @colorspace:        enum v4l2_colorspace; supplemental to pixelformat
>>>> + * @xfer_func:        enum v4l2_xfer_func, colorspace transfer function
>>>> + * @ycbcr_enc:        enum v4l2_ycbcr_encoding, Y'CbCr encoding
>>>> + * @hsv_enc:        enum v4l2_hsv_encoding, HSV encoding
>>>> + * @quantization:    enum v4l2_quantization, colorspace quantization
>>>> + * @reserved:        extra space reserved for future fields, must be set to 0
>>>> + */
>>>> +struct v4l2_ext_pix_format {
>>>> +    __u32 type;
>>>> +    __u32 width;
>>>> +    __u32 height;
>>>> +    __u32 field;
>>>> +    struct v4l2_plane_pix_format plane_fmt[VIDEO_MAX_PLANES];
>>>> +    __u32 pixelformat;
>>>> +    __u64 modifier;
>>>> +    __u32 colorspace;
>>>> +    __u32 xfer_func;
>>>> +    union {
>>>> +        __u32 ycbcr_enc;
>>>> +        __u32 hsv_enc;
>>>> +    };
>>>> +    __u32 quantization;
>>>> +    __u32 reserved[9];
>>>> +};
>>>> +
>>>>   /**
>>>>    * struct v4l2_sdr_format - SDR format definition
>>>>    * @pixelformat:    little endian four character code (fourcc)
>>>> @@ -2583,6 +2620,10 @@ struct v4l2_create_buffers {
>>>>   #define VIDIOC_QUERY_EXT_CTRL    _IOWR('V', 103, struct v4l2_query_ext_ctrl)
>>>> +#define VIDIOC_G_EXT_PIX_FMT    _IOWR('V', 104, struct v4l2_ext_pix_format)
>>>> +#define VIDIOC_S_EXT_PIX_FMT    _IOWR('V', 105, struct v4l2_ext_pix_format)
>>>> +#define VIDIOC_TRY_EXT_PIX_FMT    _IOWR('V', 106, struct v4l2_ext_pix_format)
>>>> +
>>>>   /* Reminder: when adding new ioctls please add support for them to
>>>>      drivers/media/v4l2-core/v4l2-compat-ioctl32.c as well! */
>>>>
>>>
>>> Regards,
>>>
>>>     Hans
>>>
>>
>