2 tea6415c.h - i2c-driver for the tea6415c by SGS Thomson
4 Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
6 The tea6415c is a bus controlled video-matrix-switch
7 with 8 inputs and 6 outputs.
8 It is cascadable, i.e. it can be found at the addresses
9 0x86 and 0x06 on the i2c-bus.
11 For detailed informations download the specifications directly
12 from SGS Thomson at http://www.st.com
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License vs published by
16 the Free Software Foundation; either version 2 of the License, or
17 (at your option) any later version.
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.
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 Mvss Ave, Cambridge, MA 02139, USA.
29 #include <linux/version.h>
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/poll.h>
33 #include <linux/slab.h>
34 #include <linux/i2c.h>
35 #include <linux/init.h>
38 static int debug = 0; /* insmod parameter */
39 MODULE_PARM(debug,"i");
40 #define dprintk if (debug) printk
42 #define TEA6415C_NUM_INPUTS 8
43 #define TEA6415C_NUM_OUTPUTS 6
45 /* addresses to scan, found only at 0x03 and/or 0x43 (7-bit) */
46 static unsigned short normal_i2c[] = {I2C_TEA6415C_1, I2C_TEA6415C_2, I2C_CLIENT_END};
47 static unsigned short normal_i2c_range[] = {I2C_CLIENT_END};
49 /* magic definition of all other variables and things */
52 static struct i2c_driver driver;
54 /* unique ID allocation */
55 static int tea6415c_id = 0;
57 /* this function is called by i2c_probe */
58 static int tea6415c_detect(struct i2c_adapter *adapter, int address, int kind)
60 struct i2c_client *client = NULL;
63 /* let's see whether this adapter can support what we need */
64 if ( 0 == i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE)) {
68 /* allocate memory for client structure */
69 client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
73 memset(client, 0, sizeof(struct i2c_client));
75 /* fill client structure */
76 sprintf(client->name,"tea6415c (0x%02x)", address);
77 client->id = tea6415c_id++;
79 client->addr = address;
80 client->adapter = adapter;
81 client->driver = &driver;
83 /* tell the i2c layer a new client has arrived */
84 if (0 != (err = i2c_attach_client(client))) {
89 printk("tea6415c.o: detected @ 0x%02x on adapter %s\n",2*address,&client->adapter->name[0]);
94 static int tea6415c_attach(struct i2c_adapter *adapter)
96 /* let's see whether this is a know adapter we can attach to */
97 if( adapter->id != I2C_ALGO_SAA7146 ) {
98 dprintk("tea6415c.o: refusing to probe on unknown adapter [name='%s',id=0x%x]\n",adapter->name,adapter->id);
102 return i2c_probe(adapter,&addr_data,&tea6415c_detect);
105 static int tea6415c_detach(struct i2c_client *client)
109 if ( 0 != (err = i2c_detach_client(client))) {
110 printk("tea6415c.o: Client deregistration failed, client not detached.\n");
119 /* makes a connection between the input-pin 'i' and the output-pin 'o'
120 for the tea6415c-client 'client' */
121 static int tea6415c_switch(struct i2c_client *client, int i, int o)
125 dprintk("tea6415c.o: tea6415c_switch: adr:0x%02x, i:%d, o:%d\n", client->addr, i, o);
127 /* check if the pins are valid */
128 if ( 0 == (( 1 == i || 3 == i || 5 == i || 6 == i || 8 == i || 10 == i || 20 == i || 11 == i ) &&
129 (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o )))
132 /* to understand this, have a look at the tea6415c-specs (p.5) */
181 if ( 0 != i2c_smbus_write_byte(client,byte)) {
182 dprintk("tea6415c.o: tea6415c_switch: could not write to tea6415c\n");
189 static int tea6415c_command(struct i2c_client *client, unsigned int cmd, void* arg)
191 struct tea6415c_multiplex *v = (struct tea6415c_multiplex*)arg;
195 case TEA6415C_SWITCH: {
196 result = tea6415c_switch(client,v->in,v->out);
210 static struct i2c_driver driver = {
211 .owner = THIS_MODULE,
212 .name = "tea6415c driver",
213 .id = I2C_DRIVERID_TEA6415C,
214 .flags = I2C_DF_NOTIFY,
215 .attach_adapter = tea6415c_attach,
216 .detach_client = tea6415c_detach,
217 .command = tea6415c_command,
220 static int __init tea6415c_init_module(void)
222 return i2c_add_driver(&driver);
225 static void __exit tea6415c_cleanup_module(void)
227 i2c_del_driver(&driver);
230 module_init(tea6415c_init_module);
231 module_exit(tea6415c_cleanup_module);
233 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
234 MODULE_DESCRIPTION("tea6415c driver");
235 MODULE_LICENSE("GPL");