drivers/usb/gadget/legacy/ether.c

Source file repositories/reference/linux-study-clean/drivers/usb/gadget/legacy/ether.c

File Facts

System
Linux kernel
Corpus path
drivers/usb/gadget/legacy/ether.c
Extension
.c
Size
13425 bytes
Lines
485
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.

Dependency Surface

Detected Declarations

Annotated Snippet

if (IS_ERR(fi_rndis)) {
			status = PTR_ERR(fi_rndis);
			goto fail;
		}

		rndis_borrow_net(fi_rndis, net);

		device_desc.idVendor = cpu_to_le16(RNDIS_VENDOR_NUM);
		device_desc.idProduct = cpu_to_le16(RNDIS_PRODUCT_NUM);
		device_desc.bNumConfigurations = 2;
	}

	/* Allocate string descriptor numbers ... note that string
	 * contents can be overridden by the composite_dev glue.
	 */

	status = usb_string_ids_tab(cdev, strings_dev);
	if (status < 0)
		goto fail1;
	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;

	if (gadget_is_otg(gadget) && !otg_desc[0]) {
		struct usb_descriptor_header *usb_desc;

		usb_desc = usb_otg_descriptor_alloc(gadget);
		if (!usb_desc) {
			status = -ENOMEM;
			goto fail1;
		}
		usb_otg_descriptor_init(gadget, usb_desc);
		otg_desc[0] = usb_desc;
		otg_desc[1] = NULL;
	}

	/* register our configuration(s); RNDIS first, if it's used */
	if (has_rndis()) {
		status = usb_add_config(cdev, &rndis_config_driver,
				rndis_do_config);
		if (status < 0)
			goto fail2;
	}

	status = usb_add_config(cdev, &eth_config_driver, eth_do_config);
	if (status < 0)
		goto fail2;

	usb_composite_overwrite_options(cdev, &coverwrite);
	dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
			DRIVER_DESC);

	return 0;

fail2:
	kfree(otg_desc[0]);
	otg_desc[0] = NULL;
fail1:
	if (has_rndis())
		usb_put_function_instance(fi_rndis);
fail:
	if (use_eem)
		usb_put_function_instance(fi_eem);
	else if (can_support_ecm(gadget))
		usb_put_function_instance(fi_ecm);
	else
		usb_put_function_instance(fi_geth);
	return status;
}

static int eth_unbind(struct usb_composite_dev *cdev)
{
	if (has_rndis()) {
		usb_put_function(f_rndis);
		usb_put_function_instance(fi_rndis);
	}
	if (use_eem) {
		usb_put_function(f_eem);
		usb_put_function_instance(fi_eem);
	} else if (can_support_ecm(cdev->gadget)) {
		usb_put_function(f_ecm);
		usb_put_function_instance(fi_ecm);
	} else {
		usb_put_function(f_geth);
		usb_put_function_instance(fi_geth);
	}
	kfree(otg_desc[0]);
	otg_desc[0] = NULL;

	return 0;
}

Annotation

Implementation Notes