drivers/comedi/range.c

Source file repositories/reference/linux-study-clean/drivers/comedi/range.c

File Facts

System: Linux kernel
Corpus path: drivers/comedi/range.c
Extension: .c
Size: 3899 bytes
Lines: 132
Domain: Driver Families
Bucket: drivers/comedi
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.
Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

linux/uaccess.h
linux/comedi/comedidev.h
comedi_internal.h

Detected Declarations

function do_rangeinfo_ioctl
function comedi_check_chanlist
export range_bipolar10
export range_bipolar5
export range_bipolar2_5
export range_unipolar10
export range_unipolar5
export range_unipolar2_5
export range_0_20mA
export range_4_20mA
export range_0_32mA
export range_unknown
export comedi_check_chanlist

Annotated Snippet

CR_RANGE(chanspec) >= range_len) {
			dev_warn(dev->class_dev,
				 "bad chanlist[%d]=0x%08x chan=%d range length=%d\n",
				 i, chanspec, chan, range_len);
			return -EINVAL;
		}
	}
	return 0;
}
EXPORT_SYMBOL_GPL(comedi_check_chanlist);

Annotation

Immediate include surface: `linux/uaccess.h`, `linux/comedi/comedidev.h`, `comedi_internal.h`.
Detected declarations: `function do_rangeinfo_ioctl`, `function comedi_check_chanlist`, `export range_bipolar10`, `export range_bipolar5`, `export range_bipolar2_5`, `export range_unipolar10`, `export range_unipolar5`, `export range_unipolar2_5`, `export range_0_20mA`, `export range_4_20mA`.
Atlas domain: Driver Families / drivers/comedi.
Implementation status: integration implementation candidate.
This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.

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.