arch/sh/drivers/dma/dma-api.c

File Facts

System

Linux kernel

Corpus path

arch/sh/drivers/dma/dma-api.c

Extension

.c

Size

6103 bytes

Lines

275

Domain

Architecture Layer

Bucket

arch/sh

Inferred role

Architecture Layer: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
• 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/init.h
• linux/module.h
• linux/spinlock.h
• linux/proc_fs.h
• linux/seq_file.h
• linux/list.h
• linux/platform_device.h
• linux/mm.h
• linux/sched.h
• linux/slab.h
• asm/dma.h

Detected Declarations

• function get_nr_channels
• function get_dma_residue
• function request_dma
• function free_dma
• function dma_wait_for_completion
• function dma_configure_channel
• function dma_xfer
• function dma_proc_show
• function register_dmac
• function unregister_dmac
• function dma_api_init
• module init dma_api_init
• export get_dma_info
• export get_dma_channel
• export get_dma_residue
• export request_dma
• export free_dma
• export dma_wait_for_completion
• export dma_configure_channel
• export dma_xfer
• export register_dmac
• export unregister_dmac

Annotated Snippet

subsys_initcall(dma_api_init);

MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
MODULE_DESCRIPTION("DMA API for SuperH");
MODULE_LICENSE("GPL v2");

Annotation

• Immediate include surface: `linux/init.h`, `linux/module.h`, `linux/spinlock.h`, `linux/proc_fs.h`, `linux/seq_file.h`, `linux/list.h`, `linux/platform_device.h`, `linux/mm.h`.
• Detected declarations: `function get_nr_channels`, `function get_dma_residue`, `function request_dma`, `function free_dma`, `function dma_wait_for_completion`, `function dma_configure_channel`, `function dma_xfer`, `function dma_proc_show`, `function register_dmac`, `function unregister_dmac`.
• Atlas domain: Architecture Layer / arch/sh.
• 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.