media: uvcvideo: implement UVC v1.5 ROI

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.

Reviewed-by: Ricardo Ribalda <[e-mail]>
Signed-off-by: Yunke Cao <[e-mail]>
Reviewed-by: Yunke Cao <[e-mail]>
Tested-by: Yunke Cao <[e-mail]>
Reviewed-by: Hans de Goede <[e-mail]>
Signed-off-by: Ricardo Ribalda <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Hans de Goede <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
[hverkuil: fix control names: "Of" -> "of", "Controls" -> "Ctrls"]

drivers/media/usb/uvc/uvc_ctrl.c

···
 		.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[] = {
···
 		       buf, sizeof(*buf));
 
 	return out_mapping;
+}
+
+static int uvc_get_rect(struct uvc_control_mapping *mapping, u8 query,
+			const void *uvc_in, size_t v4l2_size, void *v4l2_out)
+{
+	const struct uvc_rect *uvc_rect = uvc_in;
+	struct v4l2_rect *v4l2_rect = v4l2_out;
+
+	if (WARN_ON(v4l2_size != sizeof(struct v4l2_rect)))
+		return -EINVAL;
+
+	if (uvc_rect->left > uvc_rect->right ||
+	    uvc_rect->top > uvc_rect->bottom)
+		return -EIO;
+
+	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 uvc_set_rect(struct uvc_control_mapping *mapping, size_t v4l2_size,
+			const void *v4l2_in, void *uvc_out)
+{
+	struct uvc_rect *uvc_rect = uvc_out;
+	const struct v4l2_rect *v4l2_rect = v4l2_in;
+
+	if (WARN_ON(v4l2_size != sizeof(struct v4l2_rect)))
+		return -EINVAL;
+
+	uvc_rect->top = min(0xffff, v4l2_rect->top);
+	uvc_rect->left = min(0xffff, v4l2_rect->left);
+	uvc_rect->bottom = min(0xffff, v4l2_rect->top + v4l2_rect->height - 1);
+	uvc_rect->right = min(0xffff, v4l2_rect->left + v4l2_rect->width - 1);
+
+	return 0;
 }
 
 static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
···
 		.entity		= UVC_GUID_UVC_PROCESSING,
 		.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
 		.filter_mapping	= uvc_ctrl_filter_plf_mapping,
+	},
+	{
+		.id		= V4L2_CID_UVC_REGION_OF_INTEREST_RECT,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_REGION_OF_INTEREST_CONTROL,
+		.size		= sizeof(struct uvc_rect) * 8,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_RECT,
+		.data_type	= UVC_CTRL_DATA_TYPE_RECT,
+		.get		= uvc_get_rect,
+		.set		= uvc_set_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,
+		.size		= 16,
+		.offset		= 64,
+		.v4l2_type	= V4L2_CTRL_TYPE_BITMASK,
+		.data_type	= UVC_CTRL_DATA_TYPE_BITMASK,
+		.name		= "Region of Interest Auto Ctrls",
 	},
 };
 
···
 
 static size_t uvc_mapping_v4l2_size(struct uvc_control_mapping *mapping)
 {
+	if (mapping->v4l2_type == V4L2_CTRL_TYPE_RECT)
+		return sizeof(struct v4l2_rect);
+
 	if (uvc_ctrl_mapping_is_compound(mapping))
 		return DIV_ROUND_UP(mapping->size, 8);
 

drivers/media/usb/uvc/uvcvideo.h

···
 	u16	uvc_version;
 };
 
+struct uvc_rect {
+	u16 top;
+	u16 left;
+	u16 bottom;
+	u16 right;
+} __packed;
+
 struct uvc_status_streaming {
 	u8	button;
 } __packed;

include/uapi/linux/usb/video.h

···
 #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

include/uapi/linux/uvcvideo.h

···
 #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)
···
 	 UVC_CTRL_FLAG_GET_DEF)
 
 #define UVC_MENU_NAME_LEN 32
+
+/* V4L2 driver-specific controls */
+#define V4L2_CID_UVC_REGION_OF_INTEREST_RECT	(V4L2_CID_USER_UVC_BASE + 1)
+#define V4L2_CID_UVC_REGION_OF_INTEREST_AUTO	(V4L2_CID_USER_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;

include/uapi/linux/v4l2-controls.h

···
  */
 #define V4L2_CID_USER_THP7312_BASE		(V4L2_CID_USER_BASE + 0x11c0)
 
+/*
+ * 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_USER_UVC_BASE			(V4L2_CID_USER_BASE + 0x11e0)
+
 /* MPEG-class control IDs */
 /* The MPEG controls are applicable to all codec controls
  * and the 'MPEG' part of the define is historical */