drivers/staging/greybus/loopback.c

File Facts

System

Linux kernel

Corpus path

drivers/staging/greybus/loopback.c

Extension

.c

Size

30707 bytes

Lines

1180

Domain

Driver Families

Bucket

drivers/staging

Inferred role

Driver Families: exported/initcall integration point

Status

integration 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.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• 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/kernel.h
• linux/module.h
• linux/mutex.h
• linux/slab.h
• linux/kthread.h
• linux/delay.h
• linux/random.h
• linux/sizes.h
• linux/cdev.h
• linux/fs.h
• linux/kfifo.h
• linux/debugfs.h
• linux/list_sort.h
• linux/spinlock.h
• linux/workqueue.h
• linux/atomic.h
• linux/pm_runtime.h
• linux/greybus.h
• asm/div64.h

Detected Declarations

• struct gb_loopback_stats
• struct gb_loopback_device
• struct gb_loopback_async_operation
• struct gb_loopback
• function gb_loopback_check_attr
• function gb_loopback_nsec_to_usec_latency
• function __gb_loopback_calc_latency
• function gb_loopback_calc_latency
• function gb_loopback_operation_sync
• function gb_loopback_async_wait_all
• function gb_loopback_async_operation_callback
• function gb_loopback_async_operation
• function gb_loopback_sync_sink
• function gb_loopback_sync_transfer
• function gb_loopback_sync_ping
• function gb_loopback_async_sink
• function gb_loopback_async_transfer_complete
• function gb_loopback_async_transfer
• function gb_loopback_async_ping
• function gb_loopback_request_handler
• function gb_loopback_reset_stats
• function gb_loopback_update_stats
• function gb_loopback_update_stats_window
• function gb_loopback_requests_update
• function gb_loopback_throughput_update
• function gb_loopback_calculate_latency_stats
• function gb_loopback_calculate_stats
• function gb_loopback_async_wait_to_send
• function gb_loopback_fn
• function gb_loopback_dbgfs_latency_show_common
• function gb_loopback_dbgfs_latency_show
• function gb_loopback_probe
• function gb_loopback_disconnect
• function loopback_init
• function loopback_exit
• module init loopback_init

Annotated Snippet

module_init(loopback_init);

static void __exit loopback_exit(void)
{
	debugfs_remove_recursive(gb_dev.root);
	greybus_deregister(&gb_loopback_driver);
	class_unregister(&loopback_class);
	ida_destroy(&loopback_ida);
}
module_exit(loopback_exit);

MODULE_DESCRIPTION("Loopback bridge driver for the Greybus loopback module");
MODULE_LICENSE("GPL v2");

Annotation

• Immediate include surface: `linux/kernel.h`, `linux/module.h`, `linux/mutex.h`, `linux/slab.h`, `linux/kthread.h`, `linux/delay.h`, `linux/random.h`, `linux/sizes.h`.
• Detected declarations: `struct gb_loopback_stats`, `struct gb_loopback_device`, `struct gb_loopback_async_operation`, `struct gb_loopback`, `function gb_loopback_check_attr`, `function gb_loopback_nsec_to_usec_latency`, `function __gb_loopback_calc_latency`, `function gb_loopback_calc_latency`, `function gb_loopback_operation_sync`, `function gb_loopback_async_wait_all`.
• Atlas domain: Driver Families / drivers/staging.
• Implementation status: integration 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.