[mirror_ubuntu-artful-kernel.git] / drivers / media / video / tea6420.c

 /*
    tea6420 - i2c-driver for the tea6420 by SGS Thomson

    Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>

    The tea6420 is a bus controlled audio-matrix with 5 stereo inputs,
    4 stereo outputs and gain control for each output.
    It is cascadable, i.e. it can be found at the adresses 0x98
    and 0x9a 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 "tea6420.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]: ", KBUILD_MODNAME, __FUNCTION__, __LINE__); printk(args); } } while (0)

/* addresses to scan, found only at 0x4c and/or 0x4d (7-Bit) */
static unsigned short normal_i2c[] = { I2C_TEA6420_1, I2C_TEA6420_2, 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;

/* make a connection between the input 'i' and the output 'o'
   with gain 'g' for the tea6420-client 'client' (note: i = 6 means 'mute') */
static int tea6420_switch(struct i2c_client *client, int i, int o, int g)
{
	u8 byte = 0;
	int ret;

	dprintk("adr:0x%02x, i:%d, o:%d, g:%d\n", client->addr, i, o, g);

	/* check if the paramters are valid */
	if (i < 1 || i > 6 || o < 1 || o > 4 || g < 0 || g > 6 || g % 2 != 0)
		return -1;

	byte  = ((o - 1) << 5);
	byte |= (i - 1);

	/* to understand this, have a look at the tea6420-specs (p.5) */
	switch (g) {
	case 0:
		byte |= (3 << 3);
		break;
	case 2:
		byte |= (2 << 3);
		break;
	case 4:
		byte |= (1 << 3);
		break;
	case 6:
		break;
	}

	ret = i2c_smbus_write_byte(client, byte);
	if (ret) {
		dprintk("i2c_smbus_write_byte() failed, ret:%d\n", ret);
		return -EIO;
	}
	
	return 0;
}

/* this function is called by i2c_probe */
static int tea6420_detect(struct i2c_adapter *adapter, int address, int kind)
{
	struct i2c_client *client;
	int err = 0, i = 0;

	/* let's see whether this adapter can support what we need */
	if (0 == i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE)) {
		return 0;
	}

	/* allocate memory for client structure */
	client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
	if (0 == client) {
		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 != (err = i2c_attach_client(client))) {
		kfree(client);
		return err;
	}

	/* set initial values: set "mute"-input to all outputs at gain 0 */
	err = 0;
	for (i = 1; i < 5; i++) {
		err += tea6420_switch(client, 6, i, 0);
	}
	if (err) {
		dprintk("could not initialize tea6420\n");
		kfree(client);
		return -ENODEV;
	}

	printk("tea6420: 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_HW_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, &tea6420_detect);
}

static int detach(struct i2c_client *client)
{
	int ret = i2c_detach_client(client);
	kfree(client);
	return ret;
}

static int command(struct i2c_client *client, unsigned int cmd, void *arg)
{
	struct tea6420_multiplex *a = (struct tea6420_multiplex *)arg;
	int result = 0;

	switch (cmd) {
	case TEA6420_SWITCH:
		result = tea6420_switch(client, a->in, a->out, a->gain);
		break;
	default:
		return -ENOIOCTLCMD;
	}

	return result;
}

static struct i2c_driver driver = {
	.driver = {
		.name	= "tea6420",
	},
	.id	= I2C_DRIVERID_TEA6420,
	.attach_adapter	= attach,
	.detach_client	= detach,
	.command	= command,
};

static struct i2c_client client_template = {
	.name = "tea6420",
	.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("tea6420 driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	tea6420 - i2c-driver for the tea6420 by SGS Thomson
	3
	4	Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
	5
	6	The tea6420 is a bus controlled audio-matrix with 5 stereo inputs,
	7	4 stereo outputs and gain control for each output.
	8	It is cascadable, i.e. it can be found at the adresses 0x98
	9	and 0x9a on the i2c-bus.
	10
	11	For detailed informations download the specifications directly
	12	from SGS Thomson at http://www.st.com
	13
	14	This program is free software; you can redistribute it and/or modify
	15	it under the terms of the GNU General Public License as published by
	16	the Free Software Foundation; either version 2 of the License, or
	17	(at your option) any later version.
	18
	19	This program is distributed in the hope that it will be useful,
	20	but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	GNU General Public License for more details.
	23
	24	You should have received a copy of the GNU General Public License
	25	along with this program; if not, write to the Free Software
	26	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	27	*/
	28
	29	#include <linux/module.h>
	30	#include <linux/ioctl.h>
	31	#include <linux/i2c.h>
	32
	33	#include "tea6420.h"
	34
	35	static int debug = 0; /* insmod parameter */
	36	module_param(debug, int, 0644);
	37	MODULE_PARM_DESC(debug, "Turn on/off device debugging (default:off).");
	38	#define dprintk(args...) \
367cb704	39	do { if (debug) { printk("%s: %s()[%d]: ", KBUILD_MODNAME, __FUNCTION__, __LINE__); printk(args); } } while (0)
1da177e4 LT	40
	41	/* addresses to scan, found only at 0x4c and/or 0x4d (7-Bit) */
	42	static unsigned short normal_i2c[] = { I2C_TEA6420_1, I2C_TEA6420_2, I2C_CLIENT_END };
1da177e4 LT	43
	44	/* magic definition of all other variables and things */
	45	I2C_CLIENT_INSMOD;
	46
	47	static struct i2c_driver driver;
	48	static struct i2c_client client_template;
	49
	50	/* make a connection between the input 'i' and the output 'o'
	51	with gain 'g' for the tea6420-client 'client' (note: i = 6 means 'mute') */
	52	static int tea6420_switch(struct i2c_client *client, int i, int o, int g)
	53	{
	54	u8 byte = 0;
	55	int ret;
	56
	57	dprintk("adr:0x%02x, i:%d, o:%d, g:%d\n", client->addr, i, o, g);
	58
	59	/* check if the paramters are valid */
	60	if (i < 1 \|\| i > 6 \|\| o < 1 \|\| o > 4 \|\| g < 0 \|\| g > 6 \|\| g % 2 != 0)
	61	return -1;
	62
	63	byte = ((o - 1) << 5);
	64	byte \|= (i - 1);
	65
	66	/* to understand this, have a look at the tea6420-specs (p.5) */
	67	switch (g) {
	68	case 0:
	69	byte \|= (3 << 3);
	70	break;
	71	case 2:
	72	byte \|= (2 << 3);
	73	break;
	74	case 4:
	75	byte \|= (1 << 3);
	76	break;
	77	case 6:
	78	break;
	79	}
	80
	81	ret = i2c_smbus_write_byte(client, byte);
	82	if (ret) {
	83	dprintk("i2c_smbus_write_byte() failed, ret:%d\n", ret);
	84	return -EIO;
	85	}
	86
	87	return 0;
	88	}
	89
	90	/* this function is called by i2c_probe */
	91	static int tea6420_detect(struct i2c_adapter *adapter, int address, int kind)
	92	{
	93	struct i2c_client *client;
	94	int err = 0, i = 0;
	95
	96	/* let's see whether this adapter can support what we need */
	97	if (0 == i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE)) {
	98	return 0;
	99	}
	100
	101	/* allocate memory for client structure */
7408187d	102	client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
1da177e4 LT	103	if (0 == client) {
	104	return -ENOMEM;
	105	}
1da177e4 LT	106
	107	/* fill client structure */
	108	memcpy(client, &client_template, sizeof(struct i2c_client));
	109	client->addr = address;
	110	client->adapter = adapter;
	111
	112	/* tell the i2c layer a new client has arrived */
	113	if (0 != (err = i2c_attach_client(client))) {
	114	kfree(client);
	115	return err;
	116	}
	117
	118	/* set initial values: set "mute"-input to all outputs at gain 0 */
	119	err = 0;
	120	for (i = 1; i < 5; i++) {
	121	err += tea6420_switch(client, 6, i, 0);
	122	}
	123	if (err) {
	124	dprintk("could not initialize tea6420\n");
	125	kfree(client);
	126	return -ENODEV;
	127	}
	128
	129	printk("tea6420: detected @ 0x%02x on adapter %s\n", address, &client->adapter->name[0]);
	130
	131	return 0;
	132	}
	133
	134	static int attach(struct i2c_adapter *adapter)
	135	{
	136	/* let's see whether this is a know adapter we can attach to */
1684a984	137	if (adapter->id != I2C_HW_SAA7146) {
1da177e4 LT	138	dprintk("refusing to probe on unknown adapter [name='%s',id=0x%x]\n", adapter->name, adapter->id);
	139	return -ENODEV;
	140	}
	141
	142	return i2c_probe(adapter, &addr_data, &tea6420_detect);
	143	}
	144
	145	static int detach(struct i2c_client *client)
	146	{
	147	int ret = i2c_detach_client(client);
	148	kfree(client);
	149	return ret;
	150	}
	151
	152	static int command(struct i2c_client client, unsigned int cmd, void arg)
	153	{
	154	struct tea6420_multiplex a = (struct tea6420_multiplex )arg;
	155	int result = 0;
	156
	157	switch (cmd) {
	158	case TEA6420_SWITCH:
	159	result = tea6420_switch(client, a->in, a->out, a->gain);
	160	break;
	161	default:
	162	return -ENOIOCTLCMD;
	163	}
	164
	165	return result;
	166	}
	167
	168	static struct i2c_driver driver = {
604f28e2	169	.driver = {
604f28e2 LR	170	.name = "tea6420",
604f28e2 LR	171	},
1da177e4	172	.id = I2C_DRIVERID_TEA6420,
1da177e4 LT	173	.attach_adapter = attach,
	174	.detach_client = detach,
	175	.command = command,
	176	};
	177
	178	static struct i2c_client client_template = {
fae91e72	179	.name = "tea6420",
1da177e4 LT	180	.driver = &driver,
	181	};
	182
	183	static int __init this_module_init(void)
	184	{
	185	return i2c_add_driver(&driver);
	186	}
	187
	188	static void __exit this_module_exit(void)
	189	{
	190	i2c_del_driver(&driver);
	191	}
	192
	193	module_init(this_module_init);
	194	module_exit(this_module_exit);
	195
	196	MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
	197	MODULE_DESCRIPTION("tea6420 driver");
	198	MODULE_LICENSE("GPL");