drivers/dma/pch_dma.c

File Facts

System

Linux kernel

Corpus path

drivers/dma/pch_dma.c

Extension

.c

Size

25336 bytes

Lines

991

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/dmaengine.h
• linux/dma-mapping.h
• linux/init.h
• linux/pci.h
• linux/slab.h
• linux/interrupt.h
• linux/module.h
• linux/pch_dma.h
• dmaengine.h

Detected Declarations

• struct pch_dma_desc_regs
• struct pch_dma_regs
• struct pch_dma_desc
• struct pch_dma_chan
• struct pch_dma
• function pdc_enable_irq
• function pdc_set_dir
• function pdc_set_mode
• function pdc_get_status0
• function pdc_get_status2
• function pdc_is_idle
• function pdc_dostart
• function pdc_chain_complete
• function pdc_complete_all
• function pdc_handle_error
• function pdc_advance_work
• function pd_tx_submit
• function pdc_desc_put
• function pd_alloc_chan_resources
• function pd_free_chan_resources
• function pd_tx_status
• function pd_issue_pending
• function for_each_sg
• function pd_device_terminate_all
• function pdc_tasklet
• function pd_irq
• function pch_dma_save_regs
• function list_for_each_entry_safe
• function pch_dma_restore_regs
• function list_for_each_entry_safe
• function pch_dma_suspend
• function pch_dma_resume
• function pch_dma_probe
• function pch_dma_remove
• function list_for_each_entry_safe

Annotated Snippet

static struct pci_driver pch_dma_driver = {
	.name		= DRV_NAME,
	.id_table	= pch_dma_id_table,
	.probe		= pch_dma_probe,
	.remove		= pch_dma_remove,
	.driver.pm	= &pch_dma_pm_ops,
};

module_pci_driver(pch_dma_driver);

MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "
		   "DMA controller driver");
MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DEVICE_TABLE(pci, pch_dma_id_table);

Annotation

• Immediate include surface: `linux/dmaengine.h`, `linux/dma-mapping.h`, `linux/init.h`, `linux/pci.h`, `linux/slab.h`, `linux/interrupt.h`, `linux/module.h`, `linux/pch_dma.h`.
• Detected declarations: `struct pch_dma_desc_regs`, `struct pch_dma_regs`, `struct pch_dma_desc`, `struct pch_dma_chan`, `struct pch_dma`, `function pdc_enable_irq`, `function pdc_set_dir`, `function pdc_set_mode`, `function pdc_get_status0`, `function pdc_get_status2`.
• 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.