drivers/dma/sh/shdmac.c

File Facts

System

Linux kernel

Corpus path

drivers/dma/sh/shdmac.c

Extension

.c

Size

24302 bytes

Lines

944

Domain

Driver Families

Bucket

drivers/dma

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.
• 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/delay.h
• linux/dmaengine.h
• linux/err.h
• linux/init.h
• linux/interrupt.h
• linux/kdebug.h
• linux/module.h
• linux/notifier.h
• linux/of.h
• linux/platform_device.h
• linux/pm_runtime.h
• linux/rculist.h
• linux/sh_dma.h
• linux/slab.h
• linux/spinlock.h
• ../dmaengine.h
• shdma.h

Detected Declarations

• function channel_clear
• function sh_dmae_writel
• function sh_dmae_readl
• function dmaor_read
• function dmaor_write
• function chcr_write
• function chcr_read
• function sh_dmae_ctl_stop
• function sh_dmae_rst
• function dmae_is_busy
• function calc_xmit_shift
• function log2size_to_chcr
• function dmae_set_reg
• function dmae_start
• function dmae_init
• function dmae_set_chcr
• function dmae_set_dmars
• function sh_dmae_start_xfer
• function sh_dmae_channel_busy
• function sh_dmae_setup_xfer
• function sh_dmae_set_slave
• function dmae_halt
• function sh_dmae_desc_setup
• function sh_dmae_halt
• function sh_dmae_chan_irq
• function sh_dmae_get_partial
• function sh_dmae_reset
• function sh_dmae_err
• function sh_dmae_desc_completed
• function sh_dmae_nmi_notify
• function sh_dmae_nmi_handler
• function sh_dmae_chan_probe
• function sh_dmae_chan_remove
• function shdma_for_each_chan
• function sh_dmae_runtime_suspend
• function sh_dmae_runtime_resume
• function sh_dmae_suspend
• function sh_dmae_resume
• function sh_dmae_slave_addr
• function sh_dmae_probe
• function sh_dmae_remove
• function sh_dmae_init
• function sh_dmae_exit
• module init sh_dmae_init

Annotated Snippet

module_init(sh_dmae_init);

static void __exit sh_dmae_exit(void)
{
	platform_driver_unregister(&sh_dmae_driver);

	unregister_die_notifier(&sh_dmae_nmi_notifier);
}
module_exit(sh_dmae_exit);

MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" SH_DMAE_DRV_NAME);

Annotation

• Immediate include surface: `linux/delay.h`, `linux/dmaengine.h`, `linux/err.h`, `linux/init.h`, `linux/interrupt.h`, `linux/kdebug.h`, `linux/module.h`, `linux/notifier.h`.
• Detected declarations: `function channel_clear`, `function sh_dmae_writel`, `function sh_dmae_readl`, `function dmaor_read`, `function dmaor_write`, `function chcr_write`, `function chcr_read`, `function sh_dmae_ctl_stop`, `function sh_dmae_rst`, `function dmae_is_busy`.
• Atlas domain: Driver Families / drivers/dma.
• Implementation status: integration 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.