android_kernel_xiaomi_sm8350/drivers/media/video/tda9840.c
Jean Delvare b3d5496ea5 [PATCH] I2C: Kill address ranges in non-sensors i2c chip drivers
Some months ago, you killed the address ranges mechanism from all
sensors i2c chip drivers (both the module parameters and the in-code
address lists). I think it was a very good move, as the ranges can
easily be replaced by individual addresses, and this allowed for
significant cleanups in the i2c core (let alone the impressive size
shrink for all these drivers).

Unfortunately you did not do the same for non-sensors i2c chip drivers.
These need the address ranges even less, so we could get rid of the
ranges here as well for another significant i2c core cleanup. Here comes
a patch which does just that. Since the process is exactly the same as
what you did for the other drivers set already, I did not split this one
in parts.

A documentation update is included.

The change saves 308 bytes in the i2c core, and an average 1382 bytes
for chip drivers which use I2C_CLIENT_INSMOD, 126 bytes for those which
do not.

This change is required if we want to merge the sensors and non-sensors
i2c code (and we want to do this).

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Index: gregkh-2.6/Documentation/i2c/writing-clients
===================================================================
2005-06-21 21:51:48 -07:00

254 lines
6.3 KiB
C

/*
tda9840 - i2c-driver for the tda9840 by SGS Thomson
Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
The tda9840 is a stereo/dual sound processor with digital
identification. It can be found at address 0x84 on the i2c-bus.
For detailed informations download the specifications directly
from SGS Thomson at http://www.st.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/ioctl.h>
#include <linux/i2c.h>
#include "tda9840.h"
static int debug = 0; /* insmod parameter */
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off device debugging (default:off).");
#define dprintk(args...) \
do { if (debug) { printk("%s: %s()[%d]: ",__stringify(KBUILD_MODNAME), __FUNCTION__, __LINE__); printk(args); } } while (0)
#define SWITCH 0x00
#define LEVEL_ADJUST 0x02
#define STEREO_ADJUST 0x03
#define TEST 0x04
/* addresses to scan, found only at 0x42 (7-Bit) */
static unsigned short normal_i2c[] = { I2C_TDA9840, I2C_CLIENT_END };
/* magic definition of all other variables and things */
I2C_CLIENT_INSMOD;
static struct i2c_driver driver;
static struct i2c_client client_template;
static int command(struct i2c_client *client, unsigned int cmd, void *arg)
{
int result;
int byte = *(int *)arg;
switch (cmd) {
case TDA9840_SWITCH:
dprintk("TDA9840_SWITCH: 0x%02x\n", byte);
if (byte != TDA9840_SET_MONO
&& byte != TDA9840_SET_MUTE
&& byte != TDA9840_SET_STEREO
&& byte != TDA9840_SET_LANG1
&& byte != TDA9840_SET_LANG2
&& byte != TDA9840_SET_BOTH
&& byte != TDA9840_SET_BOTH_R
&& byte != TDA9840_SET_EXTERNAL) {
return -EINVAL;
}
result = i2c_smbus_write_byte_data(client, SWITCH, byte);
if (result)
dprintk("i2c_smbus_write_byte() failed, ret:%d\n", result);
break;
case TDA9840_LEVEL_ADJUST:
dprintk("TDA9840_LEVEL_ADJUST: %d\n", byte);
/* check for correct range */
if (byte > 25 || byte < -20)
return -EINVAL;
/* calculate actual value to set, see specs, page 18 */
byte /= 5;
if (0 < byte)
byte += 0x8;
else
byte = -byte;
result = i2c_smbus_write_byte_data(client, LEVEL_ADJUST, byte);
if (result)
dprintk("i2c_smbus_write_byte() failed, ret:%d\n", result);
break;
case TDA9840_STEREO_ADJUST:
dprintk("TDA9840_STEREO_ADJUST: %d\n", byte);
/* check for correct range */
if (byte > 25 || byte < -24)
return -EINVAL;
/* calculate actual value to set */
byte /= 5;
if (0 < byte)
byte += 0x20;
else
byte = -byte;
result = i2c_smbus_write_byte_data(client, STEREO_ADJUST, byte);
if (result)
dprintk("i2c_smbus_write_byte() failed, ret:%d\n", result);
break;
case TDA9840_DETECT: {
int *ret = (int *)arg;
byte = i2c_smbus_read_byte_data(client, STEREO_ADJUST);
if (byte == -1) {
dprintk("i2c_smbus_read_byte_data() failed\n");
return -EIO;
}
if (0 != (byte & 0x80)) {
dprintk("TDA9840_DETECT: register contents invalid\n");
return -EINVAL;
}
dprintk("TDA9840_DETECT: byte: 0x%02x\n", byte);
*ret = ((byte & 0x60) >> 5);
result = 0;
break;
}
case TDA9840_TEST:
dprintk("TDA9840_TEST: 0x%02x\n", byte);
/* mask out irrelevant bits */
byte &= 0x3;
result = i2c_smbus_write_byte_data(client, TEST, byte);
if (result)
dprintk("i2c_smbus_write_byte() failed, ret:%d\n", result);
break;
default:
return -ENOIOCTLCMD;
}
if (result)
return -EIO;
return 0;
}
static int detect(struct i2c_adapter *adapter, int address, int kind)
{
struct i2c_client *client;
int result = 0;
int byte = 0x0;
/* let's see whether this adapter can support what we need */
if (0 == i2c_check_functionality(adapter,
I2C_FUNC_SMBUS_READ_BYTE_DATA |
I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) {
return 0;
}
/* allocate memory for client structure */
client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
if (0 == client) {
printk("not enough kernel memory\n");
return -ENOMEM;
}
/* fill client structure */
memcpy(client, &client_template, sizeof(struct i2c_client));
client->addr = address;
client->adapter = adapter;
/* tell the i2c layer a new client has arrived */
if (0 != (result = i2c_attach_client(client))) {
kfree(client);
return result;
}
/* set initial values for level & stereo - adjustment, mode */
byte = 0;
result = command(client, TDA9840_LEVEL_ADJUST, &byte);
result += command(client, TDA9840_STEREO_ADJUST, &byte);
byte = TDA9840_SET_MONO;
result = command(client, TDA9840_SWITCH, &byte);
if (result) {
dprintk("could not initialize tda9840\n");
return -ENODEV;
}
printk("tda9840: detected @ 0x%02x on adapter %s\n", address, &client->adapter->name[0]);
return 0;
}
static int attach(struct i2c_adapter *adapter)
{
/* let's see whether this is a know adapter we can attach to */
if (adapter->id != I2C_ALGO_SAA7146) {
dprintk("refusing to probe on unknown adapter [name='%s',id=0x%x]\n", adapter->name, adapter->id);
return -ENODEV;
}
return i2c_probe(adapter, &addr_data, &detect);
}
static int detach(struct i2c_client *client)
{
int ret = i2c_detach_client(client);
kfree(client);
return ret;
}
static struct i2c_driver driver = {
.owner = THIS_MODULE,
.name = "tda9840",
.id = I2C_DRIVERID_TDA9840,
.flags = I2C_DF_NOTIFY,
.attach_adapter = attach,
.detach_client = detach,
.command = command,
};
static struct i2c_client client_template = {
I2C_DEVNAME("tda9840"),
.driver = &driver,
};
static int __init this_module_init(void)
{
return i2c_add_driver(&driver);
}
static void __exit this_module_exit(void)
{
i2c_del_driver(&driver);
}
module_init(this_module_init);
module_exit(this_module_exit);
MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
MODULE_DESCRIPTION("tda9840 driver");
MODULE_LICENSE("GPL");