diff mbox series

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

Message ID 20220628075705.2278044-5-yunkec@google.com
State New
Headers show
Series media: Implement UVC v1.5 ROI | expand

Commit Message

Yunke Cao June 28, 2022, 7:57 a.m. UTC
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@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(-)

Comments

Laurent Pinchart Aug. 24, 2022, 8:36 p.m. UTC | #1
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 ?

> +}
> +
> +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 ?

> +
> +	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,
> +	},
>  };
>  
>  /* ------------------------------------------------------------------------
> @@ -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.

> +		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)
Ricardo Ribalda Sept. 28, 2022, 8:13 a.m. UTC | #2
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
diff mbox series

Patch

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
+	 * 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;
+}
+
+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;
+}
+
+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;
+
+	uvc_rect = (struct uvc_rect *)(data + mapping->offset / 8);
+	uvc_to_v4l2_rect((struct v4l2_rect *)data_out, uvc_rect);
+
+	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;
+
+	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,
+		.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,
+	},
 };
 
 /* ------------------------------------------------------------------------
@@ -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);
+		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
+	 * 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.
+	 *
+	 * 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);
+	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);
 			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 */
+
+/*
+ * The base for the uvc driver controls. See linux/uvcvideo.h for the list
+ * of controls. We reserve 16 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)