drivers/usb/usbip/vudc_transfer.c

File Facts

System

Linux kernel

Corpus path

drivers/usb/usbip/vudc_transfer.c

Extension

.c

Size

11993 bytes

Lines

498

Domain

Driver Families

Bucket

drivers/usb

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.

• 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.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/usb.h
• linux/timer.h
• linux/usb/ch9.h
• vudc.h

Detected Declarations

• function Copyright
• function handle_control_request
• function transfer
• function v_timer
• function v_init_timer
• function v_start_timer
• function v_kick_timer
• function v_stop_timer

Annotated Snippet

if (setup->bRequestType == DEV_REQUEST) {
			ret_val = 0;
			switch (w_value) {
			case USB_DEVICE_REMOTE_WAKEUP:
				break;
			case USB_DEVICE_B_HNP_ENABLE:
				udc->gadget.b_hnp_enable = 1;
				break;
			case USB_DEVICE_A_HNP_SUPPORT:
				udc->gadget.a_hnp_support = 1;
				break;
			case USB_DEVICE_A_ALT_HNP_SUPPORT:
				udc->gadget.a_alt_hnp_support = 1;
				break;
			default:
				ret_val = -EOPNOTSUPP;
			}
			if (ret_val == 0) {
				udc->devstatus |= (1 << w_value);
				*status = 0;
			}
		} else if (setup->bRequestType == EP_REQUEST) {
			/* endpoint halt */
			ep2 = vudc_find_endpoint(udc, w_index);
			if (!ep2 || ep2->ep.name == udc->ep[0].ep.name) {
				ret_val = -EOPNOTSUPP;
				break;
			}
			ep2->halted = 1;
			ret_val = 0;
			*status = 0;
		}
		break;
	case USB_REQ_CLEAR_FEATURE:
		if (setup->bRequestType == DEV_REQUEST) {
			ret_val = 0;
			switch (w_value) {
			case USB_DEVICE_REMOTE_WAKEUP:
				w_value = USB_DEVICE_REMOTE_WAKEUP;
				break;

			case USB_DEVICE_U1_ENABLE:
			case USB_DEVICE_U2_ENABLE:
			case USB_DEVICE_LTM_ENABLE:
				ret_val = -EOPNOTSUPP;
				break;
			default:
				ret_val = -EOPNOTSUPP;
				break;
			}
			if (ret_val == 0) {
				udc->devstatus &= ~(1 << w_value);
				*status = 0;
			}
		} else if (setup->bRequestType == EP_REQUEST) {
			/* endpoint halt */
			ep2 = vudc_find_endpoint(udc, w_index);
			if (!ep2) {
				ret_val = -EOPNOTSUPP;
				break;
			}
			if (!ep2->wedged)
				ep2->halted = 0;
			ret_val = 0;
			*status = 0;
		}
		break;
	case USB_REQ_GET_STATUS:
		if (setup->bRequestType == DEV_INREQUEST
				|| setup->bRequestType == INTF_INREQUEST
				|| setup->bRequestType == EP_INREQUEST) {
			char *buf;
			/*
			 * device: remote wakeup, selfpowered
			 * interface: nothing
			 * endpoint: halt
			 */
			buf = (char *)urb->transfer_buffer;
			if (urb->transfer_buffer_length > 0) {
				if (setup->bRequestType == EP_INREQUEST) {
					ep2 = vudc_find_endpoint(udc, w_index);
					if (!ep2) {
						ret_val = -EOPNOTSUPP;
						break;
					}
					buf[0] = ep2->halted;
				} else if (setup->bRequestType ==
					   DEV_INREQUEST) {
					buf[0] = (u8)udc->devstatus;
				} else

Annotation

• Immediate include surface: `linux/usb.h`, `linux/timer.h`, `linux/usb/ch9.h`, `vudc.h`.
• Detected declarations: `function Copyright`, `function handle_control_request`, `function transfer`, `function v_timer`, `function v_init_timer`, `function v_start_timer`, `function v_kick_timer`, `function v_stop_timer`.
• Atlas domain: Driver Families / drivers/usb.
• Implementation status: source implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.