drivers/iio/potentiometer/mcp4131.c

Source file repositories/reference/linux-study-clean/drivers/iio/potentiometer/mcp4131.c

File Facts

System
Linux kernel
Corpus path
drivers/iio/potentiometer/mcp4131.c
Extension
.c
Size
15149 bytes
Lines
492
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.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mcp4131_cfg {
	int wipers;
	int max_pos;
	int kohms;
};

enum mcp4131_type {
	MCP413x_502 = 0,
	MCP413x_103,
	MCP413x_503,
	MCP413x_104,
	MCP414x_502,
	MCP414x_103,
	MCP414x_503,
	MCP414x_104,
	MCP415x_502,
	MCP415x_103,
	MCP415x_503,
	MCP415x_104,
	MCP416x_502,
	MCP416x_103,
	MCP416x_503,
	MCP416x_104,
	MCP423x_502,
	MCP423x_103,
	MCP423x_503,
	MCP423x_104,
	MCP424x_502,
	MCP424x_103,
	MCP424x_503,
	MCP424x_104,
	MCP425x_502,
	MCP425x_103,
	MCP425x_503,
	MCP425x_104,
	MCP426x_502,
	MCP426x_103,
	MCP426x_503,
	MCP426x_104,
};

static const struct mcp4131_cfg mcp4131_cfg[] = {
	[MCP413x_502] = { .wipers = 1, .max_pos = 128, .kohms =   5, },
	[MCP413x_103] = { .wipers = 1, .max_pos = 128, .kohms =  10, },
	[MCP413x_503] = { .wipers = 1, .max_pos = 128, .kohms =  50, },
	[MCP413x_104] = { .wipers = 1, .max_pos = 128, .kohms = 100, },
	[MCP414x_502] = { .wipers = 1, .max_pos = 128, .kohms =   5, },
	[MCP414x_103] = { .wipers = 1, .max_pos = 128, .kohms =  10, },
	[MCP414x_503] = { .wipers = 1, .max_pos = 128, .kohms =  50, },
	[MCP414x_104] = { .wipers = 1, .max_pos = 128, .kohms = 100, },
	[MCP415x_502] = { .wipers = 1, .max_pos = 256, .kohms =   5, },
	[MCP415x_103] = { .wipers = 1, .max_pos = 256, .kohms =  10, },
	[MCP415x_503] = { .wipers = 1, .max_pos = 256, .kohms =  50, },
	[MCP415x_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
	[MCP416x_502] = { .wipers = 1, .max_pos = 256, .kohms =   5, },
	[MCP416x_103] = { .wipers = 1, .max_pos = 256, .kohms =  10, },
	[MCP416x_503] = { .wipers = 1, .max_pos = 256, .kohms =  50, },
	[MCP416x_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
	[MCP423x_502] = { .wipers = 2, .max_pos = 128, .kohms =   5, },
	[MCP423x_103] = { .wipers = 2, .max_pos = 128, .kohms =  10, },
	[MCP423x_503] = { .wipers = 2, .max_pos = 128, .kohms =  50, },
	[MCP423x_104] = { .wipers = 2, .max_pos = 128, .kohms = 100, },
	[MCP424x_502] = { .wipers = 2, .max_pos = 128, .kohms =   5, },
	[MCP424x_103] = { .wipers = 2, .max_pos = 128, .kohms =  10, },
	[MCP424x_503] = { .wipers = 2, .max_pos = 128, .kohms =  50, },
	[MCP424x_104] = { .wipers = 2, .max_pos = 128, .kohms = 100, },
	[MCP425x_502] = { .wipers = 2, .max_pos = 256, .kohms =   5, },
	[MCP425x_103] = { .wipers = 2, .max_pos = 256, .kohms =  10, },
	[MCP425x_503] = { .wipers = 2, .max_pos = 256, .kohms =  50, },
	[MCP425x_104] = { .wipers = 2, .max_pos = 256, .kohms = 100, },
	[MCP426x_502] = { .wipers = 2, .max_pos = 256, .kohms =   5, },
	[MCP426x_103] = { .wipers = 2, .max_pos = 256, .kohms =  10, },
	[MCP426x_503] = { .wipers = 2, .max_pos = 256, .kohms =  50, },
	[MCP426x_104] = { .wipers = 2, .max_pos = 256, .kohms = 100, },
};

struct mcp4131_data {
	struct spi_device *spi;
	const struct mcp4131_cfg *cfg;
	struct mutex lock;
	u8 buf[2] __aligned(IIO_DMA_MINALIGN);
};

#define MCP4131_CHANNEL(ch) {					\
	.type = IIO_RESISTANCE,					\
	.indexed = 1,						\
	.output = 1,						\
	.channel = (ch),					\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\

Annotation

Implementation Notes