drivers/dma/switchtec_dma.c

File Facts

System

Linux kernel

Corpus path

drivers/dma/switchtec_dma.c

Extension

.c

Size

37869 bytes

Lines

1438

Domain

Driver Families

Bucket

drivers/dma

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.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• 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/bitfield.h
• linux/circ_buf.h
• linux/dmaengine.h
• linux/module.h
• linux/pci.h
• linux/delay.h
• linux/iopoll.h
• dmaengine.h

Detected Declarations

• struct chan_hw_regs
• struct chan_fw_regs
• struct switchtec_dma_chan
• struct switchtec_dma_dev
• struct switchtec_dma_hw_se_desc
• struct switchtec_dma_hw_ce
• struct switchtec_dma_desc
• enum chan_op
• enum switchtec_dma_opcode
• function wait_for_chan_status
• function halt_channel
• function unhalt_channel
• function flush_pci_write
• function reset_channel
• function pause_reset_channel
• function channel_op
• function enable_channel
• function disable_channel
• function switchtec_dma_cleanup_completed
• function switchtec_dma_abort_desc
• function switchtec_dma_chan_stop
• function switchtec_dma_terminate_all
• function switchtec_dma_synchronize
• function switchtec_dma_prep_desc
• function switchtec_dma_prep_memcpy
• function switchtec_dma_tx_submit
• function switchtec_dma_tx_status
• function switchtec_dma_issue_pending
• function switchtec_dma_pause
• function switchtec_dma_resume
• function switchtec_dma_desc_task
• function switchtec_dma_isr
• function switchtec_dma_chan_status_isr
• function list_for_each_entry
• function switchtec_dma_free_desc
• function switchtec_dma_alloc_desc
• function switchtec_dma_alloc_chan_resources
• function switchtec_dma_free_chan_resources
• function switchtec_dma_chan_init
• function switchtec_dma_chan_free
• function switchtec_dma_chans_release
• function switchtec_dma_chans_enumerate
• function switchtec_dma_release
• function switchtec_dma_create
• function switchtec_dma_probe
• function switchtec_dma_remove

Annotated Snippet

static struct pci_driver switchtec_dma_pci_driver = {
	.name           = KBUILD_MODNAME,
	.id_table       = switchtec_dma_pci_tbl,
	.probe          = switchtec_dma_probe,
	.remove		= switchtec_dma_remove,
};
module_pci_driver(switchtec_dma_pci_driver);

Annotation

• Immediate include surface: `linux/bitfield.h`, `linux/circ_buf.h`, `linux/dmaengine.h`, `linux/module.h`, `linux/pci.h`, `linux/delay.h`, `linux/iopoll.h`, `dmaengine.h`.
• Detected declarations: `struct chan_hw_regs`, `struct chan_fw_regs`, `struct switchtec_dma_chan`, `struct switchtec_dma_dev`, `struct switchtec_dma_hw_se_desc`, `struct switchtec_dma_hw_ce`, `struct switchtec_dma_desc`, `enum chan_op`, `enum switchtec_dma_opcode`, `function wait_for_chan_status`.
• Atlas domain: Driver Families / drivers/dma.
• Implementation status: pattern implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

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.