drivers/media/i2c/saa6588.c

File Facts

System

Linux kernel

Corpus path

drivers/media/i2c/saa6588.c

Extension

.c

Size

12282 bytes

Lines

513

Domain

Driver Families

Bucket

drivers/media

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.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• 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/module.h
• linux/kernel.h
• linux/i2c.h
• linux/types.h
• linux/videodev2.h
• linux/init.h
• linux/errno.h
• linux/slab.h
• linux/poll.h
• linux/wait.h
• linux/uaccess.h
• media/i2c/saa6588.h
• media/v4l2-device.h

Detected Declarations

• struct saa6588
• function block_from_buf
• function read_from_buf
• function block_to_buf
• function saa6588_i2c_poll
• function saa6588_work
• function saa6588_configure
• function saa6588_command
• function saa6588_g_tuner
• function saa6588_s_tuner
• function saa6588_probe
• function saa6588_remove

Annotated Snippet

struct saa6588 {
	struct v4l2_subdev sd;
	struct delayed_work work;
	spinlock_t lock;
	unsigned char *buffer;
	unsigned int buf_size;
	unsigned int rd_index;
	unsigned int wr_index;
	unsigned int block_count;
	unsigned char last_blocknum;
	wait_queue_head_t read_queue;
	int data_available_for_read;
	u8 sync;
};

static inline struct saa6588 *to_saa6588(struct v4l2_subdev *sd)
{
	return container_of(sd, struct saa6588, sd);
}

/* ---------------------------------------------------------------------- */

/*
 * SAA6588 defines
 */

/* Initialization and mode control byte (0w) */

/* bit 0+1 (DAC0/DAC1) */
#define cModeStandard           0x00
#define cModeFastPI             0x01
#define cModeReducedRequest     0x02
#define cModeInvalid            0x03

/* bit 2 (RBDS) */
#define cProcessingModeRDS      0x00
#define cProcessingModeRBDS     0x04

/* bit 3+4 (SYM0/SYM1) */
#define cErrCorrectionNone      0x00
#define cErrCorrection2Bits     0x08
#define cErrCorrection5Bits     0x10
#define cErrCorrectionNoneRBDS  0x18

/* bit 5 (NWSY) */
#define cSyncNormal             0x00
#define cSyncRestart            0x20

/* bit 6 (TSQD) */
#define cSigQualityDetectOFF    0x00
#define cSigQualityDetectON     0x40

/* bit 7 (SQCM) */
#define cSigQualityTriggered    0x00
#define cSigQualityContinous    0x80

/* Pause level and flywheel control byte (1w) */

/* bits 0..5 (FEB0..FEB5) */
#define cFlywheelMaxBlocksMask  0x3F
#define cFlywheelDefault        0x20

/* bits 6+7 (PL0/PL1) */
#define cPauseLevel_11mV	0x00
#define cPauseLevel_17mV        0x40
#define cPauseLevel_27mV        0x80
#define cPauseLevel_43mV        0xC0

/* Pause time/oscillator frequency/quality detector control byte (1w) */

/* bits 0..4 (SQS0..SQS4) */
#define cQualityDetectSensMask  0x1F
#define cQualityDetectDefault   0x0F

/* bit 5 (SOSC) */
#define cSelectOscFreqOFF	0x00
#define cSelectOscFreqON	0x20

/* bit 6+7 (PTF0/PTF1) */
#define cOscFreq_4332kHz	0x00
#define cOscFreq_8664kHz	0x40
#define cOscFreq_12996kHz	0x80
#define cOscFreq_17328kHz	0xC0

/* ---------------------------------------------------------------------- */

static bool block_from_buf(struct saa6588 *s, unsigned char *buf)
{
	int i;

Annotation

• Immediate include surface: `linux/module.h`, `linux/kernel.h`, `linux/i2c.h`, `linux/types.h`, `linux/videodev2.h`, `linux/init.h`, `linux/errno.h`, `linux/slab.h`.
• Detected declarations: `struct saa6588`, `function block_from_buf`, `function read_from_buf`, `function block_to_buf`, `function saa6588_i2c_poll`, `function saa6588_work`, `function saa6588_configure`, `function saa6588_command`, `function saa6588_g_tuner`, `function saa6588_s_tuner`.
• Atlas domain: Driver Families / drivers/media.
• Implementation status: source implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

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.