drivers/media/usb/uvc/uvc_entity.c

Source file repositories/reference/linux-study-clean/drivers/media/usb/uvc/uvc_entity.c

File Facts

System
Linux kernel
Corpus path
drivers/media/usb/uvc/uvc_entity.c
Extension
.c
Size
3992 bytes
Lines
162
Domain
Driver Families
Bucket
drivers/media
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

switch (UVC_ENTITY_TYPE(entity)) {
		case UVC_VC_SELECTOR_UNIT:
			function = MEDIA_ENT_F_VID_MUX;
			break;
		case UVC_VC_PROCESSING_UNIT:
		case UVC_VC_EXTENSION_UNIT:
			/* For lack of a better option. */
			function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
			break;
		case UVC_COMPOSITE_CONNECTOR:
		case UVC_COMPONENT_CONNECTOR:
			function = MEDIA_ENT_F_CONN_COMPOSITE;
			break;
		case UVC_SVIDEO_CONNECTOR:
			function = MEDIA_ENT_F_CONN_SVIDEO;
			break;
		case UVC_ITT_CAMERA:
			function = MEDIA_ENT_F_CAM_SENSOR;
			break;
		case UVC_TT_VENDOR_SPECIFIC:
		case UVC_ITT_VENDOR_SPECIFIC:
		case UVC_ITT_MEDIA_TRANSPORT_INPUT:
		case UVC_OTT_VENDOR_SPECIFIC:
		case UVC_OTT_DISPLAY:
		case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
		case UVC_EXTERNAL_VENDOR_SPECIFIC:
		case UVC_EXT_GPIO_UNIT:
		default:
			function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
			break;
		}

		entity->subdev.entity.function = function;

		ret = media_entity_pads_init(&entity->subdev.entity,
					entity->num_pads, entity->pads);

		if (ret < 0)
			return ret;

		ret = v4l2_device_register_subdev(&chain->dev->vdev,
						  &entity->subdev);
	} else if (entity->vdev != NULL) {
		ret = media_entity_pads_init(&entity->vdev->entity,
					entity->num_pads, entity->pads);
		if (entity->flags & UVC_ENTITY_FLAG_DEFAULT)
			entity->vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
	} else
		ret = 0;

	return ret;
}

int uvc_mc_register_entities(struct uvc_video_chain *chain)
{
	struct uvc_entity *entity;
	int ret;

	list_for_each_entry(entity, &chain->entities, chain) {
		ret = uvc_mc_init_entity(chain, entity);
		if (ret < 0) {
			dev_info(&chain->dev->intf->dev,
				 "Failed to initialize entity for entity %u\n",
				 entity->id);
			return ret;
		}
	}

	list_for_each_entry(entity, &chain->entities, chain) {
		ret = uvc_mc_create_links(chain, entity);
		if (ret < 0) {
			dev_info(&chain->dev->intf->dev,
				 "Failed to create links for entity %u\n",
				 entity->id);
			return ret;
		}
	}

	return 0;
}

Annotation

Implementation Notes