drivers/usb/gadget/legacy/ncm.c
Source file repositories/reference/linux-study-clean/drivers/usb/gadget/legacy/ncm.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/usb/gadget/legacy/ncm.c- Extension
.c- Size
- 5386 bytes
- Lines
- 212
- 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.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kernel.hlinux/module.hlinux/usb/composite.hu_ether.hu_ncm.h
Detected Declarations
function ncm_do_configfunction gncm_bindfunction gncm_unbind
Annotated Snippet
if (!usb_desc) {
status = -ENOMEM;
goto fail;
}
usb_otg_descriptor_init(gadget, usb_desc);
otg_desc[0] = usb_desc;
otg_desc[1] = NULL;
}
status = usb_add_config(cdev, &ncm_config_driver,
ncm_do_config);
if (status < 0)
goto fail1;
usb_composite_overwrite_options(cdev, &coverwrite);
dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
return 0;
fail1:
kfree(otg_desc[0]);
otg_desc[0] = NULL;
fail:
usb_put_function_instance(f_ncm_inst);
return status;
}
static int gncm_unbind(struct usb_composite_dev *cdev)
{
if (!IS_ERR_OR_NULL(f_ncm))
usb_put_function(f_ncm);
if (!IS_ERR_OR_NULL(f_ncm_inst))
usb_put_function_instance(f_ncm_inst);
kfree(otg_desc[0]);
otg_desc[0] = NULL;
return 0;
}
static struct usb_composite_driver ncm_driver = {
.name = "g_ncm",
.dev = &device_desc,
.strings = dev_strings,
.max_speed = USB_SPEED_SUPER,
.bind = gncm_bind,
.unbind = gncm_unbind,
};
module_usb_composite_driver(ncm_driver);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Yauheni Kaliuta");
MODULE_LICENSE("GPL");
Annotation
- Immediate include surface: `linux/kernel.h`, `linux/module.h`, `linux/usb/composite.h`, `u_ether.h`, `u_ncm.h`.
- Detected declarations: `function ncm_do_config`, `function gncm_bind`, `function gncm_unbind`.
- Atlas domain: Driver Families / drivers/usb.
- Implementation status: source implementation candidate.
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.