drivers/usb/misc/chaoskey.c

File Facts

System

Linux kernel

Corpus path

drivers/usb/misc/chaoskey.c

Extension

.c

Size

14084 bytes

Lines

607

Domain

Driver Families

Bucket

drivers/usb

Inferred role

Driver Families: operation-table or driver-model contract

Status

pattern 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 an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/module.h
• linux/slab.h
• linux/usb.h
• linux/wait.h
• linux/hw_random.h
• linux/mutex.h
• linux/uaccess.h

Detected Declarations

• struct chaoskey
• function chaoskey_free
• function chaoskey_probe
• function chaoskey_disconnect
• function chaoskey_open
• function chaoskey_release
• function chaos_read_callback
• function _chaoskey_fill
• function chaoskey_read
• function chaoskey_rng_read
• function chaoskey_suspend
• function chaoskey_resume

Annotated Snippet

static const struct file_operations chaoskey_fops = {
	.owner = THIS_MODULE,
	.read = chaoskey_read,
	.open = chaoskey_open,
	.release = chaoskey_release,
	.llseek = default_llseek,
};

/* class driver information */
static struct usb_class_driver chaoskey_class = {
	.name = "chaoskey%d",
	.fops = &chaoskey_fops,
	.minor_base = USB_CHAOSKEY_MINOR_BASE,
};

/* usb specific object needed to register this driver with the usb subsystem */
static struct usb_driver chaoskey_driver = {
	.name = DRIVER_SHORT,
	.probe = chaoskey_probe,
	.disconnect = chaoskey_disconnect,
	.suspend = chaoskey_suspend,
	.resume = chaoskey_resume,
	.reset_resume = chaoskey_resume,
	.id_table = chaoskey_table,
	.supports_autosuspend = 1,
};

module_usb_driver(chaoskey_driver);

Annotation

• Immediate include surface: `linux/module.h`, `linux/slab.h`, `linux/usb.h`, `linux/wait.h`, `linux/hw_random.h`, `linux/mutex.h`, `linux/uaccess.h`.
• Detected declarations: `struct chaoskey`, `function chaoskey_free`, `function chaoskey_probe`, `function chaoskey_disconnect`, `function chaoskey_open`, `function chaoskey_release`, `function chaos_read_callback`, `function _chaoskey_fill`, `function chaoskey_read`, `function chaoskey_rng_read`.
• Atlas domain: Driver Families / drivers/usb.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• 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.