Re: [PATCH v7 4/7] media: uvcvideo: implement UVC v1.5 ROI

Ricardo Ribalda
2022-09-28T08:13:41Z

On Mon, 29 Aug 2022 at 07:48, Yunke Cao <yunkec@google.com> wrote:
>
> Hi Laurent,
>
> Thanks for the review!
>
> On Thu, Aug 25, 2022 at 5:37 AM Laurent Pinchart
> <laurent.pinchart@ideasonboard.com> wrote:
> >
> > Hi Yunke,
> >
> > Thank you for the patch.
> >
> > On Tue, Jun 28, 2022 at 04:57:02PM +0900, 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:
> >
> > s/uvc/UVC/
> >
> > > V4L2_CID_UVC_REGION_OF_INTEREST_RECT and
> > > V4L2_CID_UVC_REGION_OF_INTEREST_AUTO.
> > >
> > > Signed-off-by: Yunke Cao <yunkec@google.com>
> > > ---
> > > drivers/media/usb/uvc/uvc_ctrl.c | 146 ++++++++++++++++++++++++++++-
> > > 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 | 8 ++
> > > 6 files changed, 178 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> > > index 508ee04afbcd..00482269233a 100644
> > > --- a/drivers/media/usb/uvc/uvc_ctrl.c
> > > +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> > > @@ -355,6 +355,23 @@ 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
> >
> > /*
> > * UVC_CTRL_...
> >
> > > + * 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[] = {
> > > @@ -429,6 +446,64 @@ static void uvc_ctrl_set_rel_speed(struct uvc_control_mapping *mapping,
> > > data[first+1] = min_t(int, abs(value), 0xff);
> > > }
> > >
> > > +static void uvc_to_v4l2_rect(struct v4l2_rect *v4l2_rect,
> > > + const struct uvc_rect *uvc_rect)
> > > +{
> > > + 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;
> >
> > What happens if the device sends a bogus value with top > bottom or left
> > > right ?
> >
>
> Hmm. I didn't think of this. I guess we should check and return -EINVAL.
>
> > > +}
> > > +
> > > +static int v4l2_to_uvc_rect(struct uvc_rect *uvc_rect,
> > > + const struct v4l2_rect *v4l2_rect)
> > > +{
> > > + // Safely converts s32 and u32 to u16.
> >
> > C-style comments.
> >
> > > + 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;
> >
> > Doesn't V4L2 adjust the control value instead ?
> >
>
> videoc-g-ext-ctrls.rst says
> " When the value is out of bounds drivers can choose to take the closest
> valid value or return an ERANGE error code, whatever seems more appropriate."
>
> I chose to return ERANGE because it's a bit easier. Is it acceptable?
>
> > > +
> > > + 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;
> > > +}
> > > +
> > > +static int uvc_get_array_rect(struct uvc_control_mapping *mapping,
> > > + const u8 *data, u8 *data_out)
> > > +{
> > > + struct uvc_rect *uvc_rect;
> > > +
> > > + if (WARN_ON(mapping->offset % 8 || mapping->size % 8))
> > > + return -EINVAL;
> > > + if (WARN_ON(mapping->size / 8 != sizeof(struct uvc_rect)))
> > > + return -EINVAL;
> > > +
> >
> > These checks should go to mapping creation time.
> >
> > > + uvc_rect = (struct uvc_rect *)(data + mapping->offset / 8);
> >
> > If the offset happens to not be a multiple of 2 bytes this will cause
> > unaligned accesses on some platforms.
> >
> > > + uvc_to_v4l2_rect((struct v4l2_rect *)data_out, uvc_rect);
> >
> > Same here if not aligned on 4 bytes.
> >
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int uvc_set_array_rect(struct uvc_control_mapping *mapping,
> > > + const u8 *data_in, u8 *data)
> > > +{
> > > + struct uvc_rect *uvc_rect;
> > > +
> > > + if (WARN_ON(mapping->offset % 8 || mapping->size % 8))
> > > + return -EINVAL;
> > > + if (WARN_ON(mapping->size / 8 != sizeof(struct uvc_rect)))
> > > + return -EINVAL;
> > > +
> >
> > Same here.
> >
> > > + 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,
> > > @@ -728,6 +803,26 @@ 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,
> > > + .size = 64,
> >
> > sizeof(struct uvc_rect)
> >
> > > + .offset = 0,
> > > + .v4l2_type = V4L2_CTRL_TYPE_RECT,
> > > + .data_type = UVC_CTRL_DATA_TYPE_RECT,
> > > + .get_array = uvc_get_array_rect,
> > > + .set_array = uvc_set_array_rect,
> > > + },
> > > + {
> > > + .id = V4L2_CID_UVC_REGION_OF_INTEREST_AUTO,
> > > + .entity = UVC_GUID_UVC_CAMERA,
> > > + .selector = UVC_CT_REGION_OF_INTEREST_CONTROL,
> > > + .size = 16,
> > > + .offset = 64,
> > > + .v4l2_type = V4L2_CTRL_TYPE_BITMASK,
> > > + .data_type = UVC_CTRL_DATA_TYPE_BITMASK,

Now that we have a private control, we need to setup the name here for
both controls.

> > > + },
> > > };
> > >
> > > /* ------------------------------------------------------------------------
> > > @@ -1061,7 +1156,16 @@ static int __uvc_ctrl_get_compound_to_user(struct uvc_control_mapping *mapping,
> > > if (WARN_ON(!mapping->size % 8))
> > > return -EINVAL;
> > >
> > > - size = mapping->size / 8;
> > > + switch (mapping->v4l2_type) {
> > > + case V4L2_CTRL_TYPE_RECT:
> > > + size = sizeof(struct v4l2_rect);
> >
> > Oohhh that sounds fragile. I'm worried we may be using mapping->size as
> > the V4L2 control size somewhere else.
> >
> > It would be safer to split the size field of uvc_control_mapping into a
> > v4l2_size and a uvc_size (or possibly data_size to match the v4l2_type
> > and data_type names) in a patch before this. This will force reviewing
> > all the users of the size field to check which size they need.
> >
>
> Thanks for the suggestion! That makes a lot of sense. I will try to implement
> this in the next version, and fix other places you pointed out.
>
> Best,
> Yunke
>
> > > + break;
> > > +
> > > + default:
> > > + size = mapping->size / 8;
> > > + break;
> > > + }
> > > +
> > > if (xctrl->size < size) {
> > > xctrl->size = size;
> > > return -ENOSPC;
> > > @@ -2578,6 +2682,40 @@ static void uvc_ctrl_prune_entity(struct uvc_device *dev,
> > > }
> > > }
> > >
> > > +static int uvc_ctrl_init_roi(struct uvc_device *dev, struct uvc_control *ctrl)
> > > +{
> > > + int ret;
> > > +
> > > + ret = uvc_query_ctrl(dev, UVC_GET_DEF, ctrl->entity->id, dev->intfnum,
> > > + UVC_CT_REGION_OF_INTEREST_CONTROL,
> > > + uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF),
> > > + ctrl->info.size);
> > > + if (ret)
> > > + goto out;
> > > +
> > > + /*
> > > + * Most firmwares have wrong GET_CURRENT configuration. E.g. it's
> >
> > s/GET_CURRENT/GET_CUR/
> >
> > > + * below GET_MIN, or have rectangle coordinates mixed up. This
> > > + * causes problems sometimes, because we are unable to set
> > > + * auto-controls value without first setting ROI rectangle to
> > > + * valid configuration.
> > > + *
> > > + * We expect that default configuration is always correct and
> > > + * is within the GET_MIN / GET_MAX boundaries.
> >
> > A dangerous expectation to make given the quality of most UVC camera
> > firmwares...
> >
> > > + *
> > > + * Set current ROI configuration to GET_DEF, so that we will
> > > + * always have properly configured ROI.
> > > + */
> > > + ret = uvc_query_ctrl(dev, UVC_SET_CUR, 1, dev->intfnum,
> > > + UVC_CT_REGION_OF_INTEREST_CONTROL,
> > > + uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF),
> > > + ctrl->info.size);
> > > +out:
> > > + if (ret)
> > > + dev_err(&dev->udev->dev, "Failed to fixup ROI (%d).\n", ret);
> >
> > s/(%d)./(%d)/
> >
> > > + return ret;
> > > +}
> > > +
> > > /*
> > > * Add control information and hardcoded stock control mappings to the given
> > > * device.
> > > @@ -2590,6 +2728,7 @@ static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain,
> > > const struct uvc_control_mapping *mapping = uvc_ctrl_mappings;
> > > const struct uvc_control_mapping *mend =
> > > mapping + ARRAY_SIZE(uvc_ctrl_mappings);
> > > + const u8 camera_entity[16] = UVC_GUID_UVC_CAMERA;
> > >
> > > /* XU controls initialization requires querying the device for control
> > > * information. As some buggy UVC devices will crash when queried
> > > @@ -2610,6 +2749,11 @@ static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain,
> > > * GET_INFO on standard controls.
> > > */
> > > uvc_ctrl_get_flags(chain->dev, ctrl, &ctrl->info);
> > > +
> > > + if (ctrl->info.selector ==
> > > + UVC_CT_REGION_OF_INTEREST_CONTROL &&
> > > + uvc_entity_match_guid(ctrl->entity, camera_entity))
> > > + uvc_ctrl_init_roi(chain->dev, ctrl);
> >
> > Should we instead add an init operation to the uvc_control_info
> > structure ?
> >
> > > break;
> > > }
> > > }
> > > diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> > > index 0366d05895a9..aad61af36271 100644
> > > --- a/drivers/media/usb/uvc/uvc_v4l2.c
> > > +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> > > @@ -998,7 +998,10 @@ 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 2f9b75faae83..9ff95bbad251 100644
> > > --- a/drivers/media/usb/uvc/uvcvideo.h
> > > +++ b/drivers/media/usb/uvc/uvcvideo.h
> > > @@ -431,6 +431,13 @@ 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..e2feee15cb1b 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 private 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 dfff69ed88f7..d85be46e46f2 100644
> > > --- a/include/uapi/linux/v4l2-controls.h
> > > +++ b/include/uapi/linux/v4l2-controls.h
> > > @@ -1013,6 +1013,14 @@ enum v4l2_auto_focus_range {
> > >
> > > #define V4L2_CID_CAMERA_SENSOR_ROTATION (V4L2_CID_CAMERA_CLASS_BASE+35)
> > >
> > > +/* CAMERA-class private control IDs */
> > > +
> >
> > Why doesn't this go in the driver-specific controls range ?
> >
> > > +/*
> > > + * The base for the uvc driver controls. See linux/uvcvideo.h for the list
> > > + * of controls. We reserve 16 controls for this driver.
> >
> > I'd reserve more just in case, UVC 1.5 has quite a few controls that may
> > not be exposed through standard V4L2 controls, especially for encoding
> > units.
> >
> > > + */
> > > +#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)
> >
> > --
> > Regards,
> >
> > Laurent Pinchart

--
Ricardo Ribalda