Re: [PATCH v10 06/11] media: uvcvideo: implement UVC v1.5 ROI

[Dan Scally <dan.scally@xxxxxxxxxxxxxxxx>]

Hello

On 16/12/2022 01:30, Yunke Cao wrote:
> Hi Dan,
>
> On Fri, Dec 16, 2022 at 12:55 AM Dan Scally <dan.scally@xxxxxxxxxxxxxxxx> wrote:
> > Hi Yunke
> >
> > On 09/11/2022 06:06, Yunke Cao wrote:
> > > Implement support for ROI as described in UVC 1.5:
> > > 4.2.2.1.20 Digital Region of Interest (ROI) Control
> > >
> > > ROI control is implemented using V4L2 control API as
> > > two UVC-specific controls:
> > > V4L2_CID_UVC_REGION_OF_INTEREST_RECT and
> > > V4L2_CID_UVC_REGION_OF_INTEREST_AUTO.
> > >
> > > Signed-off-by: Yunke Cao <yunkec@xxxxxxxxxx>
> > > Reviewed-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> > > ---
> > > Changelog since v9:
> > > - No change.
> > > Changelog since v8:
> > > - No change.
> > > Changelog since v7:
> > > - Fix a few style issues.
> > > - Only allow 4-byte aligned data.
> > > - Add control names.
> > > - Move initialization to 7/10.
> > >
> > > Question:
> > > - Is V4L2_CID_CAMERA_UVC_BASE defined correctly?
> > >     Should we use V4L2_CID_PRIVATE_BASE?
> > >
> > >    drivers/media/usb/uvc/uvc_ctrl.c   | 111 +++++++++++++++++++++++++++--
> > >    drivers/media/usb/uvc/uvc_v4l2.c   |   5 +-
> > >    drivers/media/usb/uvc/uvcvideo.h   |   7 ++
> > >    include/uapi/linux/usb/video.h     |   1 +
> > >    include/uapi/linux/uvcvideo.h      |  13 ++++
> > >    include/uapi/linux/v4l2-controls.h |   9 +++
> > >    6 files changed, 140 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> > > index 7d86aa695b34..6279a3edf944 100644
> > > --- a/drivers/media/usb/uvc/uvc_ctrl.c
> > > +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> > > @@ -356,6 +356,24 @@ static const struct uvc_control_info uvc_ctrls[] = {
> > >                .flags          = UVC_CTRL_FLAG_GET_CUR
> > >                                | UVC_CTRL_FLAG_AUTO_UPDATE,
> > >        },
> > > +     /*
> > > +      * UVC_CTRL_FLAG_AUTO_UPDATE is needed because the RoI may get updated
> > > +      * by sensors.
> > > +      * "This RoI should be the same as specified in most recent SET_CUR
> > > +      * except in the case where the ‘Auto Detect and Track’ and/or
> > > +      * ‘Image Stabilization’ bit have been set."
> > > +      * 4.2.2.1.20 Digital Region of Interest (ROI) Control
> > > +      */
> > > +     {
> > > +             .entity         = UVC_GUID_UVC_CAMERA,
> > > +             .selector       = UVC_CT_REGION_OF_INTEREST_CONTROL,
> > > +             .index          = 21,
> > > +             .size           = 10,
> > > +             .flags          = UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
> > > +                             | UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX
> > > +                             | UVC_CTRL_FLAG_GET_DEF
> > > +                             | UVC_CTRL_FLAG_AUTO_UPDATE,
> > > +     },
> > >    };
> > >
> > >    static const u32 uvc_control_classes[] = {
> > > @@ -431,6 +449,57 @@ static void uvc_ctrl_set_rel_speed(struct uvc_control_mapping *mapping,
> > >        data[first+1] = min_t(int, abs(value), 0xff);
> > >    }
> > >
> > > +static int uvc_to_v4l2_rect(struct v4l2_rect *v4l2_rect,
> > > +                         const struct uvc_rect *uvc_rect)
> > > +{
> > > +     if (uvc_rect->top < uvc_rect->bottom ||
> > > +         uvc_rect->right < uvc_rect->left)
> > > +             return -EINVAL;
> > > +
> > > +     v4l2_rect->top = uvc_rect->top;
> > > +     v4l2_rect->left = uvc_rect->left;
> > > +     v4l2_rect->height = uvc_rect->bottom - uvc_rect->top + 1;
> > > +     v4l2_rect->width = uvc_rect->right - uvc_rect->left + 1;
> > > +     return 0;
> > > +}
> > > +
> > > +static int v4l2_to_uvc_rect(struct uvc_rect *uvc_rect,
> > > +                         const struct v4l2_rect *v4l2_rect)
> > > +{
> > > +     /* Safely converts s32 and u32 to u16. */
> > > +     if (v4l2_rect->top > U16_MAX || v4l2_rect->top < 0 ||
> > > +         v4l2_rect->left > U16_MAX || v4l2_rect->left < 0 ||
> > > +         v4l2_rect->height > U16_MAX || v4l2_rect->height == 0 ||
> > > +         v4l2_rect->width > U16_MAX || v4l2_rect->width == 0 ||
> > > +         v4l2_rect->height + v4l2_rect->top - 1 > U16_MAX ||
> > > +         v4l2_rect->width + v4l2_rect->left - 1 > U16_MAX)
> > > +             return -ERANGE;
> > > +
> > > +     uvc_rect->top = v4l2_rect->top;
> > > +     uvc_rect->left = v4l2_rect->left;
> > > +     uvc_rect->bottom = v4l2_rect->height + v4l2_rect->top - 1;
> > > +     uvc_rect->right = v4l2_rect->width + v4l2_rect->left - 1;
> > > +     return 0;
> > > +}
> >
> > uvc_ctrl_set() clamps out of range values...which is of course hard to
> > do at that point with the compound controls, but I think it would be ok
> > to simplify this function by clamping the values from v4l2_rect.
> Sorry, I didn't get it. Do you mean clamping the value in [0, U16_MAX] ?


Sorry, that was poorly explained. I meant to the control's min, max 
values in the same way that uvc_ctrl_set() clamps controls of type 
V4L2_CTRL_TYPE_INTEGER [1], which would inherently guarantee that they 
were within 0 to U16_MAX (because the min/max for that control have to 
be within that range anyway) and so simplify this function...but the 
clamping wouldn't be in this function, it would have to be in 
uvc_set_compound_rect(), and would also necessitate re-ordering the 
series such that support for V4L2_CTRL_WHICH_MIN/MAX_VAL were added 
first. In addition to simplifying this function without that (unless I'm 
missing something) there's nothing to stop userspace from calling 
uvc_ioctl_s_try_ext_ctls() with a p_rect that is outside the min/max for 
the control.


What do you think?



[1] 
https://elixir.bootlin.com/linux/v6.1/source/drivers/media/usb/uvc/uvc_ctrl.c#L1769

> Best,
> Yunke
>
> > > +
> > > +static int uvc_get_compound_rect(struct uvc_control_mapping *mapping,
> > > +                              const u8 *data,  u8 *data_out)
> > > +{
> > > +     struct uvc_rect *uvc_rect;
> > > +
> > > +     uvc_rect = (struct uvc_rect *)(data + mapping->offset / 8);
> > > +     return uvc_to_v4l2_rect((struct v4l2_rect *)data_out, uvc_rect);
> > > +}
> > > +
> > > +static int uvc_set_compound_rect(struct uvc_control_mapping *mapping,
> > > +                              const u8 *data_in, u8 *data)
> > > +{
> > > +     struct uvc_rect *uvc_rect;
> > > +
> > > +     uvc_rect = (struct uvc_rect *)(data + mapping->offset / 8);
> > > +     return v4l2_to_uvc_rect(uvc_rect, (struct v4l2_rect *)data_in);
> > > +}
> > > +
> > >    static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
> > >        {
> > >                .id             = V4L2_CID_BRIGHTNESS,
> > > @@ -719,6 +788,29 @@ static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
> > >                .v4l2_type      = V4L2_CTRL_TYPE_BOOLEAN,
> > >                .data_type      = UVC_CTRL_DATA_TYPE_BOOLEAN,
> > >        },
> > > +     {
> > > +             .id             = V4L2_CID_UVC_REGION_OF_INTEREST_RECT,
> > > +             .entity         = UVC_GUID_UVC_CAMERA,
> > > +             .selector       = UVC_CT_REGION_OF_INTEREST_CONTROL,
> > > +             .v4l2_size      = sizeof(struct v4l2_rect) * 8,
> > > +             .data_size      = sizeof(struct uvc_rect) * 8,
> > > +             .offset         = 0,
> > > +             .v4l2_type      = V4L2_CTRL_TYPE_RECT,
> > > +             .data_type      = UVC_CTRL_DATA_TYPE_RECT,
> > > +             .get_compound   = uvc_get_compound_rect,
> > > +             .set_compound   = uvc_set_compound_rect,
> > > +             .name           = "Region Of Interest Rectangle",
> > > +     },
> > > +     {
> > > +             .id             = V4L2_CID_UVC_REGION_OF_INTEREST_AUTO,
> > > +             .entity         = UVC_GUID_UVC_CAMERA,
> > > +             .selector       = UVC_CT_REGION_OF_INTEREST_CONTROL,
> > > +             .data_size      = 16,
> > > +             .offset         = 64,
> > > +             .v4l2_type      = V4L2_CTRL_TYPE_BITMASK,
> > > +             .data_type      = UVC_CTRL_DATA_TYPE_BITMASK,
> > > +             .name           = "Region Of Interest Auto Controls",
> > > +     },
> > >    };
> > >
> > >    static const struct uvc_control_mapping uvc_ctrl_mappings_uvc11[] = {
> > > @@ -2444,12 +2536,21 @@ static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
> > >        }
> > >
> > >        if (uvc_ctrl_mapping_is_compound(map)) {
> > > -             if (map->data_size != map->v4l2_size)
> > > -                     return -EINVAL;
> > > +             switch (map->v4l2_type) {
> > > +             case V4L2_CTRL_TYPE_RECT:
> > > +                     /* Only supports 4 bytes-aligned data. */
> > > +                     if (WARN_ON(map->offset % 32))
> > > +                             return -EINVAL;
> > > +                     break;
> > > +             default:
> > > +                     if (WARN_ON(map->data_size != map->v4l2_size))
> > > +                             return -EINVAL;
> > > +
> > > +                     /* Only supports byte-aligned data. */
> > > +                     if (WARN_ON(map->offset % 8 || map->data_size % 8))
> > > +                             return -EINVAL;
> > > +             }
> > >
> > > -             /* Only supports byte-aligned data. */
> > > -             if (WARN_ON(map->offset % 8 || map->data_size % 8))
> > > -                     return -EINVAL;
> > >        }
> > >
> > >        if (!map->get && !uvc_ctrl_mapping_is_compound(map))
> > > diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> > > index 36ff1d0d6edb..52a7dc9ad4b9 100644
> > > --- a/drivers/media/usb/uvc/uvc_v4l2.c
> > > +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> > > @@ -1002,7 +1002,10 @@ static int uvc_ioctl_query_ext_ctrl(struct file *file, void *fh,
> > >        qec->step = qc.step;
> > >        qec->default_value = qc.default_value;
> > >        qec->flags = qc.flags;
> > > -     qec->elem_size = 4;
> > > +     if (qc.type == V4L2_CTRL_TYPE_RECT)
> > > +             qec->elem_size = sizeof(struct v4l2_rect);
> > > +     else
> > > +             qec->elem_size = 4;
> > >        qec->elems = 1;
> > >        qec->nr_of_dims = 0;
> > >        memset(qec->dims, 0, sizeof(qec->dims));
> > > diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> > > index 1e1bccd3b2e5..c47304a63a7d 100644
> > > --- a/drivers/media/usb/uvc/uvcvideo.h
> > > +++ b/drivers/media/usb/uvc/uvcvideo.h
> > > @@ -291,6 +291,13 @@ struct uvc_streaming_header {
> > >        u8 bTriggerUsage;
> > >    };
> > >
> > > +struct uvc_rect {
> > > +     u16 top;
> > > +     u16 left;
> > > +     u16 bottom;
> > > +     u16 right;
> > > +} __packed;
> > > +
> > >    enum uvc_buffer_state {
> > >        UVC_BUF_STATE_IDLE      = 0,
> > >        UVC_BUF_STATE_QUEUED    = 1,
> > > diff --git a/include/uapi/linux/usb/video.h b/include/uapi/linux/usb/video.h
> > > index bfdae12cdacf..9076a444758a 100644
> > > --- a/include/uapi/linux/usb/video.h
> > > +++ b/include/uapi/linux/usb/video.h
> > > @@ -104,6 +104,7 @@
> > >    #define UVC_CT_ROLL_ABSOLUTE_CONTROL                        0x0f
> > >    #define UVC_CT_ROLL_RELATIVE_CONTROL                        0x10
> > >    #define UVC_CT_PRIVACY_CONTROL                              0x11
> > > +#define UVC_CT_REGION_OF_INTEREST_CONTROL            0x14
> > >
> > >    /* A.9.5. Processing Unit Control Selectors */
> > >    #define UVC_PU_CONTROL_UNDEFINED                    0x00
> > > diff --git a/include/uapi/linux/uvcvideo.h b/include/uapi/linux/uvcvideo.h
> > > index 8288137387c0..ae5eaa14eca2 100644
> > > --- a/include/uapi/linux/uvcvideo.h
> > > +++ b/include/uapi/linux/uvcvideo.h
> > > @@ -16,6 +16,7 @@
> > >    #define UVC_CTRL_DATA_TYPE_BOOLEAN  3
> > >    #define UVC_CTRL_DATA_TYPE_ENUM             4
> > >    #define UVC_CTRL_DATA_TYPE_BITMASK  5
> > > +#define UVC_CTRL_DATA_TYPE_RECT              6
> > >
> > >    /* Control flags */
> > >    #define UVC_CTRL_FLAG_SET_CUR               (1 << 0)
> > > @@ -36,6 +37,18 @@
> > >         UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES | \
> > >         UVC_CTRL_FLAG_GET_DEF)
> > >
> > > +/* V4L2 driver-specific controls */
> > > +#define V4L2_CID_UVC_REGION_OF_INTEREST_RECT (V4L2_CID_CAMERA_UVC_BASE + 1)
> > > +#define V4L2_CID_UVC_REGION_OF_INTEREST_AUTO (V4L2_CID_CAMERA_UVC_BASE + 2)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_EXPOSURE            (1 << 0)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_IRIS                        (1 << 1)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_WHITE_BALANCE               (1 << 2)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_FOCUS                       (1 << 3)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_FACE_DETECT         (1 << 4)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_DETECT_AND_TRACK    (1 << 5)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_IMAGE_STABILIZATION (1 << 6)
> > > +#define V4L2_UVC_REGION_OF_INTEREST_AUTO_HIGHER_QUALITY              (1 << 7)
> > > +
> > >    struct uvc_menu_info {
> > >        __u32 value;
> > >        __u8 name[32];
> > > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> > > index b5e7d082b8ad..b3544355be8f 100644
> > > --- a/include/uapi/linux/v4l2-controls.h
> > > +++ b/include/uapi/linux/v4l2-controls.h
> > > @@ -1019,6 +1019,15 @@ enum v4l2_auto_focus_range {
> > >
> > >    #define V4L2_CID_CAMERA_SENSOR_ROTATION             (V4L2_CID_CAMERA_CLASS_BASE+35)
> > >
> > > +/* CAMERA-class private control IDs */
> > > +
> > > +/*
> > > + * The base for the uvc driver controls.
> > > + * See linux/uvcvideo.h for the list of controls.
> > > + * We reserve 64 controls for this driver.
> > > + */
> > > +#define V4L2_CID_CAMERA_UVC_BASE             (V4L2_CID_CAMERA_CLASS_BASE + 0x1000)
> > > +
> > >    /* FM Modulator class control IDs */
> > >
> > >    #define V4L2_CID_FM_TX_CLASS_BASE           (V4L2_CTRL_CLASS_FM_TX | 0x900)