drivers/iio/potentiometer/mcp4531.c

Source file repositories/reference/linux-study-clean/drivers/iio/potentiometer/mcp4531.c

File Facts

System: Linux kernel
Corpus path: drivers/iio/potentiometer/mcp4531.c
Extension: .c
Size: 14850 bytes
Lines: 400
Domain: Driver Families
Bucket: drivers/iio
Inferred role: Driver Families: implementation source
Status: source 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 or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

linux/module.h
linux/i2c.h
linux/err.h
linux/mod_devicetable.h
linux/property.h
linux/iio/iio.h

Detected Declarations

struct mcp4531_cfg
struct mcp4531_data
enum mcp4531_type
function mcp4531_read_raw
function mcp4531_read_avail
function mcp4531_write_raw
function mcp4531_probe

Annotated Snippet

struct mcp4531_cfg {
	int wipers;
	int avail[3];
	int kohms;
};

enum mcp4531_type {
	MCP453x_502,
	MCP453x_103,
	MCP453x_503,
	MCP453x_104,
	MCP454x_502,
	MCP454x_103,
	MCP454x_503,
	MCP454x_104,
	MCP455x_502,
	MCP455x_103,
	MCP455x_503,
	MCP455x_104,
	MCP456x_502,
	MCP456x_103,
	MCP456x_503,
	MCP456x_104,
	MCP463x_502,
	MCP463x_103,
	MCP463x_503,
	MCP463x_104,
	MCP464x_502,
	MCP464x_103,
	MCP464x_503,
	MCP464x_104,
	MCP465x_502,
	MCP465x_103,
	MCP465x_503,
	MCP465x_104,
	MCP466x_502,
	MCP466x_103,
	MCP466x_503,
	MCP466x_104,
};

static const struct mcp4531_cfg mcp4531_cfg[] = {
	[MCP453x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =   5, },
	[MCP453x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  10, },
	[MCP453x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  50, },
	[MCP453x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
	[MCP454x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =   5, },
	[MCP454x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  10, },
	[MCP454x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  50, },
	[MCP454x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
	[MCP455x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =   5, },
	[MCP455x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  10, },
	[MCP455x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  50, },
	[MCP455x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
	[MCP456x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =   5, },
	[MCP456x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  10, },
	[MCP456x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  50, },
	[MCP456x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
	[MCP463x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =   5, },
	[MCP463x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  10, },
	[MCP463x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  50, },
	[MCP463x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
	[MCP464x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =   5, },
	[MCP464x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  10, },
	[MCP464x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  50, },
	[MCP464x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
	[MCP465x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =   5, },
	[MCP465x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  10, },
	[MCP465x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  50, },
	[MCP465x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
	[MCP466x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =   5, },
	[MCP466x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  10, },
	[MCP466x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  50, },
	[MCP466x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
};

#define MCP4531_WRITE (0 << 2)
#define MCP4531_INCR  (1 << 2)
#define MCP4531_DECR  (2 << 2)
#define MCP4531_READ  (3 << 2)

#define MCP4531_WIPER_SHIFT (4)

struct mcp4531_data {
	struct i2c_client *client;
	const struct mcp4531_cfg *cfg;
};

#define MCP4531_CHANNEL(ch) {						\
	.type = IIO_RESISTANCE,						\

Annotation

Immediate include surface: `linux/module.h`, `linux/i2c.h`, `linux/err.h`, `linux/mod_devicetable.h`, `linux/property.h`, `linux/iio/iio.h`.
Detected declarations: `struct mcp4531_cfg`, `struct mcp4531_data`, `enum mcp4531_type`, `function mcp4531_read_raw`, `function mcp4531_read_avail`, `function mcp4531_write_raw`, `function mcp4531_probe`.
Atlas domain: Driver Families / drivers/iio.
Implementation status: source implementation candidate.

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.