drivers/media/video/tda9840.c

   1  /*
   2     tda9840.h - i2c-driver for the tda9840 by SGS Thomson
   3
   4     Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
   5
   6     The tda9840 is a stereo/dual sound processor with digital
   7     identification. It can be found at address 0x84 on the i2c-bus.
   8
   9     For detailed informations download the specifications directly
  10     from SGS Thomson at http://www.st.com
  11
  12     This program is free software; you can redistribute it and/or modify
  13     it under the terms of the GNU General Public License as published by
  14     the Free Software Foundation; either version 2 of the License, or
  15     (at your option) any later version.
  16
  17     This program is distributed in the hope that it will be useful,
  18     but WITHOUT ANY WARRANTY; without even the implied warranty of
  19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20     GNU General Public License for more details.
  21
  22     You should have received a copy of the GNU General Public License
  23     along with this program; if not, write to the Free Software
  24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  */
  26
  27 #include <linux/version.h>
  28 #include <linux/module.h>
  29 #include <linux/kernel.h>
  30 #include <linux/poll.h>
  31 #include <linux/slab.h>
  32 #include <linux/i2c.h>
  33 #include <linux/init.h>
  34
  35 #include "tda9840.h"
  36
  37 static int debug = 0;   /* insmod parameter */
  38 MODULE_PARM(debug,"i");
  39 #define dprintk if (debug) printk
  40
  41 #define SWITCH          0x00
  42 #define LEVEL_ADJUST    0x02
  43 #define STEREO_ADJUST   0x03
  44 #define TEST            0x04
  45
  46 /* addresses to scan, found only at 0x42 (7-Bit) */
  47 static unsigned short normal_i2c[] = {I2C_TDA9840, I2C_CLIENT_END};
  48 static unsigned short normal_i2c_range[] = {I2C_CLIENT_END};
  49
  50 /* magic definition of all other variables and things */
  51 I2C_CLIENT_INSMOD;
  52
  53 /* unique ID allocation */
  54 static int tda9840_id = 0;
  55
  56 static struct i2c_driver driver;
  57
  58 static int tda9840_command(struct i2c_client *client, unsigned int cmd, void* arg)
  59 {
  60         int result = 0;
  61
  62         switch (cmd) {
  63                 case TDA9840_SWITCH:
  64                 {
  65                         int byte = *(int*)arg;
  66
  67                         dprintk("tda9840.o: TDA9840_SWITCH: 0x%02x\n",byte);
  68
  69                         if (    byte != TDA9840_SET_MONO
  70                              && byte != TDA9840_SET_MUTE
  71                              && byte != TDA9840_SET_STEREO
  72                              && byte != TDA9840_SET_LANG1
  73                              && byte != TDA9840_SET_LANG2
  74                              && byte != TDA9840_SET_BOTH
  75                              && byte != TDA9840_SET_BOTH_R
  76                              && byte != TDA9840_SET_EXTERNAL ) {
  77                                 return -EINVAL;
  78                         }
  79
  80                         if ( 0 != (result = i2c_smbus_write_byte_data(client, SWITCH, byte))) {
  81                                 printk("tda9840.o: TDA9840_SWITCH error.\n");
  82                                 return -EFAULT;
  83                         }
  84
  85                         return 0;
  86                 }
  87
  88                 case TDA9840_LEVEL_ADJUST:
  89                 {
  90                         int  byte = *(int*)arg;
  91
  92                         dprintk("tda9840.o: TDA9840_LEVEL_ADJUST: %d\n",byte);
  93
  94                         /* check for correct range */
  95                         if ( byte > 25 || byte < -20 )
  96                                 return -EINVAL;
  97
  98                         /* calculate actual value to set, see specs, page 18 */
  99                         byte /= 5;
 100                         if ( 0 < byte )
 101                                 byte += 0x8;
 102                         else
 103                                 byte = -byte;
 104
 105                         if ( 0 != (result = i2c_smbus_write_byte_data(client, LEVEL_ADJUST, byte))) {
 106                                 printk("tda9840.o: TDA9840_LEVEL_ADJUST error.\n");
 107                                 return -EFAULT;
 108                         }
 109
 110                         return 0;
 111                 }
 112
 113                 case TDA9840_STEREO_ADJUST:
 114                 {
 115                         int  byte = *(int*)arg;
 116
 117                         dprintk("tda9840.o: TDA9840_STEREO_ADJUST: %d\n",byte);
 118
 119                         /* check for correct range */
 120                         if ( byte > 25 || byte < -24 )
 121                                 return -EINVAL;
 122
 123                         /* calculate actual value to set */
 124                         byte /= 5;
 125                         if ( 0 < byte )
 126                                 byte += 0x20;
 127                         else
 128                                 byte = -byte;
 129
 130                         if ( 0 != (result = i2c_smbus_write_byte_data(client, STEREO_ADJUST, byte))) {
 131                                 printk("tda9840.o: TDA9840_STEREO_ADJUST error.\n");
 132                                 return -EFAULT;
 133                         }
 134
 135                         return 0;
 136                 }
 137
 138                 case TDA9840_DETECT:
 139                 {
 140                         int byte = 0x0;
 141
 142                         if ( -1 == (byte = i2c_smbus_read_byte_data(client, STEREO_ADJUST))) {
 143                                 printk("tda9840.o: TDA9840_DETECT error while reading.\n");
 144                                 return -EFAULT;
 145                         }
 146
 147                         if( 0 != (byte & 0x80)) {
 148                                 dprintk("tda9840.o: TDA9840_DETECT, register contents invalid.\n");
 149                                 return -EFAULT;
 150                         }
 151
 152                         dprintk("tda9840.o: TDA9840_DETECT, result: 0x%02x (original byte)\n",byte);
 153
 154                         return ((byte & 0x60) >> 5);
 155                 }
 156
 157                 case TDA9840_TEST:
 158                 {
 159                         int  byte = *(int*)arg;
 160
 161                         dprintk("tda9840.o: TDA9840_TEST: 0x%02x\n",byte);
 162
 163                         /* mask out irrelevant bits */
 164                         byte &= 0x3;
 165
 166                         if ( 0 != (result = i2c_smbus_write_byte_data(client, TEST, byte))) {
 167                                 printk("tda9840.o: TDA9840_TEST error.\n");
 168                                 return -EFAULT;
 169                         }
 170
 171                         return 0;
 172                 }
 173
 174                 default:
 175                         return -ENOIOCTLCMD;
 176         }
 177
 178         return 0;
 179 }
 180
 181 static int tda9840_detect(struct i2c_adapter *adapter, int address, int kind)
 182 {
 183         struct  i2c_client *client;
 184         int result = 0;
 185
 186         int byte = 0x0;
 187
 188         /* let's see whether this adapter can support what we need */
 189         if ( 0 == i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA|I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) {
 190                 return 0;
 191         }
 192
 193         /* allocate memory for client structure */
 194         client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
 195         if (0 == client) {
 196                 printk("tda9840.o: not enough kernel memory.\n");
 197                 return -ENOMEM;
 198         }
 199         memset(client, 0, sizeof(struct i2c_client));
 200
 201         /* fill client structure */
 202         sprintf(client->name,"tda9840 (0x%02x)", address);
 203         client->id = tda9840_id++;
 204         client->flags = 0;
 205         client->addr = address;
 206         client->adapter = adapter;
 207         client->driver = &driver;
 208         i2c_set_clientdata(client, NULL);
 209
 210         /* tell the i2c layer a new client has arrived */
 211         if (0 != (result = i2c_attach_client(client))) {
 212                 kfree(client);
 213                 return result;
 214         }
 215
 216         /* set initial values for level & stereo - adjustment, mode */
 217         byte = 0;
 218         if ( 0 != (result = tda9840_command(client, TDA9840_LEVEL_ADJUST, &byte))) {
 219                 printk("tda9840.o: could not initialize ic #1. continuing anyway. (result:%d)\n",result);
 220         }
 221
 222         if ( 0 != (result = tda9840_command(client, TDA9840_STEREO_ADJUST, &byte))) {
 223                 printk("tda9840.o: could not initialize ic #2. continuing anyway. (result:%d)\n",result);
 224         }
 225
 226         byte = TDA9840_SET_MONO;
 227         if ( 0 != (result = tda9840_command(client, TDA9840_SWITCH, &byte))) {
 228                 printk("tda9840.o: could not initialize ic #3. continuing anyway. (result:%d)\n",result);
 229         }
 230
 231         printk("tda9840.o: detected @ 0x%02x on adapter %s\n",2*address,&client->adapter->name[0]);
 232
 233         return 0;
 234 }
 235
 236 static int tda9840_attach(struct i2c_adapter *adapter)
 237 {
 238         /* let's see whether this is a know adapter we can attach to */
 239         if( adapter->id != I2C_ALGO_SAA7146 ) {
 240                 dprintk("tda9840.o: refusing to probe on unknown adapter [name='%s',id=0x%x]\n",adapter->name,adapter->id);
 241                 return -ENODEV;
 242         }
 243
 244         return i2c_probe(adapter,&addr_data,&tda9840_detect);
 245 }
 246
 247 static int tda9840_detach(struct i2c_client *client)
 248 {
 249         int err = 0;
 250
 251         if ( 0 != (err = i2c_detach_client(client))) {
 252                 printk("tda9840.o: Client deregistration failed, client not detached.\n");
 253                 return err;
 254         }
 255
 256         kfree(client);
 257
 258         return 0;
 259 }
 260
 261 static struct i2c_driver driver = {
 262         .owner          = THIS_MODULE,
 263         .name           = "tda9840 driver",
 264         .id             = I2C_DRIVERID_TDA9840,
 265         .flags          = I2C_DF_NOTIFY,
 266         .attach_adapter = tda9840_attach,
 267         .detach_client  = tda9840_detach,
 268         .command        = tda9840_command,
 269 };
 270
 271 static int tda9840_init_module(void)
 272 {
 273         i2c_add_driver(&driver);
 274         return 0;
 275 }
 276
 277 static void tda9840_cleanup_module(void)
 278 {
 279         i2c_del_driver(&driver);
 280 }
 281
 282 module_init(tda9840_init_module);
 283 module_exit(tda9840_cleanup_module);
 284
 285 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
 286 MODULE_DESCRIPTION("tda9840 driver");
 287 MODULE_LICENSE("GPL");
 288