drivers/media/dvb-frontends/cx24123.c

Source file repositories/reference/linux-study-clean/drivers/media/dvb-frontends/cx24123.c

File Facts

System
Linux kernel
Corpus path
drivers/media/dvb-frontends/cx24123.c
Extension
.c
Size
29142 bytes
Lines
1140
Domain
Driver Families
Bucket
drivers/media
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.

Dependency Surface

Detected Declarations

Annotated Snippet

struct cx24123_state {
	struct i2c_adapter *i2c;
	const struct cx24123_config *config;

	struct dvb_frontend frontend;

	/* Some PLL specifics for tuning */
	u32 VCAarg;
	u32 VGAarg;
	u32 bandselectarg;
	u32 pllarg;
	u32 FILTune;

	struct i2c_adapter tuner_i2c_adapter;

	u8 demod_rev;

	/* The Demod/Tuner can't easily provide these, we cache them */
	u32 currentfreq;
	u32 currentsymbolrate;
};

/* Various tuner defaults need to be established for a given symbol rate Sps */
static struct cx24123_AGC_val {
	u32 symbolrate_low;
	u32 symbolrate_high;
	u32 VCAprogdata;
	u32 VGAprogdata;
	u32 FILTune;
} cx24123_AGC_vals[] =
{
	{
		.symbolrate_low		= 1000000,
		.symbolrate_high	= 4999999,
		/* the specs recommend other values for VGA offsets,
		   but tests show they are wrong */
		.VGAprogdata		= (1 << 19) | (0x180 << 9) | 0x1e0,
		.VCAprogdata		= (2 << 19) | (0x07 << 9) | 0x07,
		.FILTune		= 0x27f /* 0.41 V */
	},
	{
		.symbolrate_low		=  5000000,
		.symbolrate_high	= 14999999,
		.VGAprogdata		= (1 << 19) | (0x180 << 9) | 0x1e0,
		.VCAprogdata		= (2 << 19) | (0x07 << 9) | 0x1f,
		.FILTune		= 0x317 /* 0.90 V */
	},
	{
		.symbolrate_low		= 15000000,
		.symbolrate_high	= 45000000,
		.VGAprogdata		= (1 << 19) | (0x100 << 9) | 0x180,
		.VCAprogdata		= (2 << 19) | (0x07 << 9) | 0x3f,
		.FILTune		= 0x145 /* 2.70 V */
	},
};

/*
 * Various tuner defaults need to be established for a given frequency kHz.
 * fixme: The bounds on the bands do not match the doc in real life.
 * fixme: Some of them have been moved, other might need adjustment.
 */
static struct cx24123_bandselect_val {
	u32 freq_low;
	u32 freq_high;
	u32 VCOdivider;
	u32 progdata;
} cx24123_bandselect_vals[] =
{
	/* band 1 */
	{
		.freq_low	= 950000,
		.freq_high	= 1074999,
		.VCOdivider	= 4,
		.progdata	= (0 << 19) | (0 << 9) | 0x40,
	},

	/* band 2 */
	{
		.freq_low	= 1075000,
		.freq_high	= 1177999,
		.VCOdivider	= 4,
		.progdata	= (0 << 19) | (0 << 9) | 0x80,
	},

	/* band 3 */
	{
		.freq_low	= 1178000,
		.freq_high	= 1295999,
		.VCOdivider	= 2,
		.progdata	= (0 << 19) | (1 << 9) | 0x01,

Annotation

Implementation Notes