drivers/media/i2c/tea6415c.c

Source file repositories/reference/linux-study-clean/drivers/media/i2c/tea6415c.c

File Facts

System
Linux kernel
Corpus path
drivers/media/i2c/tea6415c.c
Extension
.c
Size
3399 bytes
Lines
159
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.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-or-later
 /*
    tea6415c - i2c-driver for the tea6415c by SGS Thomson

    Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
    Copyright (C) 2008 Hans Verkuil <hverkuil@kernel.org>

    The tea6415c is a bus controlled video-matrix-switch
    with 8 inputs and 6 outputs.
    It is cascadable, i.e. it can be found at the addresses
    0x86 and 0x06 on the i2c-bus.

    For detailed information download the specifications directly
    from SGS Thomson at http://www.st.com

  */


#include <linux/module.h>
#include <linux/ioctl.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <media/v4l2-device.h>
#include "tea6415c.h"

MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
MODULE_DESCRIPTION("tea6415c driver");
MODULE_LICENSE("GPL");

static int debug;
module_param(debug, int, 0644);

MODULE_PARM_DESC(debug, "Debug level (0-1)");


/* makes a connection between the input-pin 'i' and the output-pin 'o' */
static int tea6415c_s_routing(struct v4l2_subdev *sd,
			      u32 i, u32 o, u32 config)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	u8 byte = 0;
	int ret;

	v4l2_dbg(1, debug, sd, "i=%d, o=%d\n", i, o);

	/* check if the pins are valid */
	if (0 == ((1 == i ||  3 == i ||  5 == i ||  6 == i ||  8 == i || 10 == i || 20 == i || 11 == i)
	      && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
		return -EINVAL;

	/* to understand this, have a look at the tea6415c-specs (p.5) */
	switch (o) {
	case 18:
		byte = 0x00;
		break;
	case 14:
		byte = 0x20;
		break;
	case 16:
		byte = 0x10;
		break;
	case 17:
		byte = 0x08;
		break;
	case 15:
		byte = 0x18;
		break;
	case 13:
		byte = 0x28;
		break;
	}

	switch (i) {
	case 5:
		byte |= 0x00;
		break;
	case 8:
		byte |= 0x04;
		break;
	case 3:
		byte |= 0x02;
		break;
	case 20:
		byte |= 0x06;
		break;
	case 6:
		byte |= 0x01;
		break;
	case 10:
		byte |= 0x05;

Annotation

Implementation Notes