drivers/media/tuners/mt2131.c
Source file repositories/reference/linux-study-clean/drivers/media/tuners/mt2131.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/media/tuners/mt2131.c- Extension
.c- Size
- 7261 bytes
- Lines
- 282
- 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.
- 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.
- Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
- 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.hlinux/delay.hlinux/dvb/frontend.hlinux/i2c.hlinux/slab.hmedia/dvb_frontend.hmt2131.hmt2131_priv.h
Detected Declarations
function mt2131_readregfunction mt2131_writeregfunction mt2131_writeregsfunction mt2131_set_paramsfunction mt2131_get_frequencyfunction mt2131_get_statusfunction mt2131_initfunction mt2131_releasefunction mt2131_attachexport mt2131_attach
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Driver for Microtune MT2131 "QAM/8VSB single chip tuner"
*
* Copyright (c) 2006 Steven Toth <stoth@linuxtv.org>
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/dvb/frontend.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <media/dvb_frontend.h>
#include "mt2131.h"
#include "mt2131_priv.h"
static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
#define dprintk(level,fmt, arg...) if (debug >= level) \
printk(KERN_INFO "%s: " fmt, "mt2131", ## arg)
static u8 mt2131_config1[] = {
0x01,
0x50, 0x00, 0x50, 0x80, 0x00, 0x49, 0xfa, 0x88,
0x08, 0x77, 0x41, 0x04, 0x00, 0x00, 0x00, 0x32,
0x7f, 0xda, 0x4c, 0x00, 0x10, 0xaa, 0x78, 0x80,
0xff, 0x68, 0xa0, 0xff, 0xdd, 0x00, 0x00
};
static u8 mt2131_config2[] = {
0x10,
0x7f, 0xc8, 0x0a, 0x5f, 0x00, 0x04
};
static int mt2131_readreg(struct mt2131_priv *priv, u8 reg, u8 *val)
{
struct i2c_msg msg[2] = {
{ .addr = priv->cfg->i2c_address, .flags = 0,
.buf = ®, .len = 1 },
{ .addr = priv->cfg->i2c_address, .flags = I2C_M_RD,
.buf = val, .len = 1 },
};
if (i2c_transfer(priv->i2c, msg, 2) != 2) {
printk(KERN_WARNING "mt2131 I2C read failed\n");
return -EREMOTEIO;
}
return 0;
}
static int mt2131_writereg(struct mt2131_priv *priv, u8 reg, u8 val)
{
u8 buf[2] = { reg, val };
struct i2c_msg msg = { .addr = priv->cfg->i2c_address, .flags = 0,
.buf = buf, .len = 2 };
if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
printk(KERN_WARNING "mt2131 I2C write failed\n");
return -EREMOTEIO;
}
return 0;
}
static int mt2131_writeregs(struct mt2131_priv *priv,u8 *buf, u8 len)
{
struct i2c_msg msg = { .addr = priv->cfg->i2c_address,
.flags = 0, .buf = buf, .len = len };
if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
printk(KERN_WARNING "mt2131 I2C write failed (len=%i)\n",
(int)len);
return -EREMOTEIO;
}
return 0;
}
static int mt2131_set_params(struct dvb_frontend *fe)
{
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
struct mt2131_priv *priv;
int ret=0, i;
u32 freq;
u8 if_band_center;
u32 f_lo1, f_lo2;
u32 div1, num1, div2, num2;
u8 b[8];
Annotation
- Immediate include surface: `linux/module.h`, `linux/delay.h`, `linux/dvb/frontend.h`, `linux/i2c.h`, `linux/slab.h`, `media/dvb_frontend.h`, `mt2131.h`, `mt2131_priv.h`.
- Detected declarations: `function mt2131_readreg`, `function mt2131_writereg`, `function mt2131_writeregs`, `function mt2131_set_params`, `function mt2131_get_frequency`, `function mt2131_get_status`, `function mt2131_init`, `function mt2131_release`, `function mt2131_attach`, `export mt2131_attach`.
- Atlas domain: Driver Families / drivers/media.
- Implementation status: integration 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.