Re: [PATCH v17 16/17] media: uvcvideo: implement UVC v1.5 ROI

From: Hans Verkuil
Date: Mon Mar 03 2025 - 09:58:39 EST

On 03/03/2025 15:02, Hans de Goede wrote:
> Hi,
>
> On 3-Mar-25 14:32, Hans Verkuil wrote:
>> Hans, Laurent, Yunke,
>>
>> On 03/02/2025 12:55, Ricardo Ribalda wrote:
>>> From: Yunke Cao <yunkec@xxxxxxxxxx>
>>>
>>> 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 <ribalda@xxxxxxxxxxxx>
>>> Signed-off-by: Yunke Cao <yunkec@xxxxxxxxxx>
>>> Reviewed-by: Yunke Cao <yunkec@xxxxxxxxxx>
>>> Tested-by: Yunke Cao <yunkec@xxxxxxxxxx>
>>> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
>>> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
>>> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
>>> ---
>>> drivers/media/usb/uvc/uvc_ctrl.c | 81 ++++++++++++++++++++++++++++++++++++++
>>> 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 | 7 ++++
>>> 5 files changed, 109 insertions(+)
>>>
>>> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
>>> index 17a7ce525f71..1906ce5b7d50 100644
>>> --- a/drivers/media/usb/uvc/uvc_ctrl.c
>>> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
>>> @@ -358,6 +358,24 @@ 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[] = {
>>> @@ -603,6 +621,44 @@ static const struct uvc_control_mapping *uvc_ctrl_filter_plf_mapping(
>>> 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[] = {
>>> {
>>> .id = V4L2_CID_BRIGHTNESS,
>>> @@ -897,6 +953,28 @@ static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
>>> .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",
>>
>> According to how titles are capitalized in english, this should be lower-case "of".
>>
>>> + },
>>> + {
>>> + .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 Controls",
>>
>> Ditto.
>>
>> This string is also one character too long (the control description string is at
>> most 31 characters). Suggested alternatives:
>>
>> "Region of Interest Auto Ctrls"
>
> FWIW my vote goes to the above one, rationale:
>
> 1. ROI is unclear
> 2. "Ctrls" with the _s_ over "Control" as this is a bitmask which allows
> multiple options to be set at the same time (so not a menu style control)
>
>> "ROI Auto Controls"
>> "Region Of Interest Auto Control"
>>
>> I can make the changes myself, but I need to know which alternative to use for
>> this string.
>
> Regards,
>
> Hans

Thank you for your quick reply! I'll merge it with this change.

Regards,

Hans

>
>
>
>
>
>>
>>> + },
>>> };
>>>
>>> /* ------------------------------------------------------------------------
>>> @@ -1473,6 +1551,9 @@ static int __uvc_queryctrl_boundaries(struct uvc_video_chain *chain,
>>>
>>> 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);
>>>
>>> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
>>> index 6fc1cb9e99d1..b63720e21075 100644
>>> --- a/drivers/media/usb/uvc/uvcvideo.h
>>> +++ b/drivers/media/usb/uvc/uvcvideo.h
>>> @@ -543,6 +543,13 @@ struct uvc_device_info {
>>> u16 uvc_version;
>>> };
>>>
>>> +struct uvc_rect {
>>> + u16 top;
>>> + u16 left;
>>> + u16 bottom;
>>> + u16 right;
>>> +} __packed;
>>> +
>>> struct uvc_status_streaming {
>>> u8 button;
>>> } __packed;
>>> diff --git a/include/uapi/linux/usb/video.h b/include/uapi/linux/usb/video.h
>>> index 526b5155e23c..e1d9f5773187 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 f86185456dc5..cbe15bca9569 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)
>>> @@ -38,6 +39,18 @@
>>>
>>> #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;
>>> __u8 name[UVC_MENU_NAME_LEN];
>>> diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
>>> index 974fd254e573..72e32814ea83 100644
>>> --- a/include/uapi/linux/v4l2-controls.h
>>> +++ b/include/uapi/linux/v4l2-controls.h
>>> @@ -215,6 +215,13 @@ enum v4l2_colorfx {
>>> */
>>> #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 */
>>>
>>
>>
>