Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Mauro Carvalho Chehab | a8733ca | 2006-03-17 10:37:02 -0300 | [diff] [blame] | 29 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <linux/module.h> |
| 31 | #include <linux/ioctl.h> |
| 32 | #include <linux/i2c.h> |
| 33 | |
| 34 | #include "tea6420.h" |
| 35 | |
| 36 | static int debug = 0; /* insmod parameter */ |
| 37 | module_param(debug, int, 0644); |
| 38 | MODULE_PARM_DESC(debug, "Turn on/off device debugging (default:off)."); |
| 39 | #define dprintk(args...) \ |
Mauro Carvalho Chehab | d56410e | 2006-03-25 09:19:53 -0300 | [diff] [blame^] | 40 | do { if (debug) { printk("%s: %s()[%d]: ", KBUILD_MODNAME, __FUNCTION__, __LINE__); printk(args); } } while (0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
| 42 | /* addresses to scan, found only at 0x4c and/or 0x4d (7-Bit) */ |
Mauro Carvalho Chehab | 09df1c1 | 2006-03-18 08:31:34 -0300 | [diff] [blame] | 43 | static unsigned short normal_i2c[] = { I2C_ADDR_TEA6420_1, I2C_ADDR_TEA6420_2, I2C_CLIENT_END }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | |
| 45 | /* magic definition of all other variables and things */ |
| 46 | I2C_CLIENT_INSMOD; |
| 47 | |
| 48 | static struct i2c_driver driver; |
| 49 | static struct i2c_client client_template; |
| 50 | |
| 51 | /* make a connection between the input 'i' and the output 'o' |
| 52 | with gain 'g' for the tea6420-client 'client' (note: i = 6 means 'mute') */ |
| 53 | static int tea6420_switch(struct i2c_client *client, int i, int o, int g) |
| 54 | { |
| 55 | u8 byte = 0; |
| 56 | int ret; |
| 57 | |
| 58 | dprintk("adr:0x%02x, i:%d, o:%d, g:%d\n", client->addr, i, o, g); |
| 59 | |
| 60 | /* check if the paramters are valid */ |
| 61 | if (i < 1 || i > 6 || o < 1 || o > 4 || g < 0 || g > 6 || g % 2 != 0) |
| 62 | return -1; |
| 63 | |
| 64 | byte = ((o - 1) << 5); |
| 65 | byte |= (i - 1); |
| 66 | |
| 67 | /* to understand this, have a look at the tea6420-specs (p.5) */ |
| 68 | switch (g) { |
| 69 | case 0: |
| 70 | byte |= (3 << 3); |
| 71 | break; |
| 72 | case 2: |
| 73 | byte |= (2 << 3); |
| 74 | break; |
| 75 | case 4: |
| 76 | byte |= (1 << 3); |
| 77 | break; |
| 78 | case 6: |
| 79 | break; |
| 80 | } |
| 81 | |
| 82 | ret = i2c_smbus_write_byte(client, byte); |
| 83 | if (ret) { |
| 84 | dprintk("i2c_smbus_write_byte() failed, ret:%d\n", ret); |
| 85 | return -EIO; |
| 86 | } |
Mauro Carvalho Chehab | a8733ca | 2006-03-17 10:37:02 -0300 | [diff] [blame] | 87 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | /* this function is called by i2c_probe */ |
| 92 | static int tea6420_detect(struct i2c_adapter *adapter, int address, int kind) |
| 93 | { |
| 94 | struct i2c_client *client; |
| 95 | int err = 0, i = 0; |
| 96 | |
| 97 | /* let's see whether this adapter can support what we need */ |
| 98 | if (0 == i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE)) { |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | /* allocate memory for client structure */ |
Panagiotis Issaris | 7408187 | 2006-01-11 19:40:56 -0200 | [diff] [blame] | 103 | client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | if (0 == client) { |
| 105 | return -ENOMEM; |
| 106 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | |
| 108 | /* fill client structure */ |
| 109 | memcpy(client, &client_template, sizeof(struct i2c_client)); |
| 110 | client->addr = address; |
| 111 | client->adapter = adapter; |
| 112 | |
| 113 | /* tell the i2c layer a new client has arrived */ |
| 114 | if (0 != (err = i2c_attach_client(client))) { |
| 115 | kfree(client); |
| 116 | return err; |
| 117 | } |
| 118 | |
| 119 | /* set initial values: set "mute"-input to all outputs at gain 0 */ |
| 120 | err = 0; |
| 121 | for (i = 1; i < 5; i++) { |
| 122 | err += tea6420_switch(client, 6, i, 0); |
| 123 | } |
| 124 | if (err) { |
| 125 | dprintk("could not initialize tea6420\n"); |
| 126 | kfree(client); |
| 127 | return -ENODEV; |
| 128 | } |
| 129 | |
| 130 | printk("tea6420: detected @ 0x%02x on adapter %s\n", address, &client->adapter->name[0]); |
| 131 | |
| 132 | return 0; |
| 133 | } |
| 134 | |
| 135 | static int attach(struct i2c_adapter *adapter) |
| 136 | { |
| 137 | /* let's see whether this is a know adapter we can attach to */ |
Jean Delvare | 1684a984 | 2005-08-11 23:51:10 +0200 | [diff] [blame] | 138 | if (adapter->id != I2C_HW_SAA7146) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | dprintk("refusing to probe on unknown adapter [name='%s',id=0x%x]\n", adapter->name, adapter->id); |
| 140 | return -ENODEV; |
| 141 | } |
| 142 | |
| 143 | return i2c_probe(adapter, &addr_data, &tea6420_detect); |
| 144 | } |
| 145 | |
| 146 | static int detach(struct i2c_client *client) |
| 147 | { |
| 148 | int ret = i2c_detach_client(client); |
| 149 | kfree(client); |
| 150 | return ret; |
| 151 | } |
| 152 | |
| 153 | static int command(struct i2c_client *client, unsigned int cmd, void *arg) |
| 154 | { |
| 155 | struct tea6420_multiplex *a = (struct tea6420_multiplex *)arg; |
| 156 | int result = 0; |
| 157 | |
| 158 | switch (cmd) { |
| 159 | case TEA6420_SWITCH: |
| 160 | result = tea6420_switch(client, a->in, a->out, a->gain); |
| 161 | break; |
| 162 | default: |
| 163 | return -ENOIOCTLCMD; |
| 164 | } |
| 165 | |
| 166 | return result; |
| 167 | } |
| 168 | |
| 169 | static struct i2c_driver driver = { |
Laurent Riffard | 604f28e | 2005-11-26 20:43:39 +0100 | [diff] [blame] | 170 | .driver = { |
Mauro Carvalho Chehab | a8733ca | 2006-03-17 10:37:02 -0300 | [diff] [blame] | 171 | .name = "tea6420", |
Laurent Riffard | 604f28e | 2005-11-26 20:43:39 +0100 | [diff] [blame] | 172 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | .id = I2C_DRIVERID_TEA6420, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | .attach_adapter = attach, |
| 175 | .detach_client = detach, |
| 176 | .command = command, |
| 177 | }; |
| 178 | |
| 179 | static struct i2c_client client_template = { |
Jean Delvare | fae91e7 | 2005-08-15 19:57:04 +0200 | [diff] [blame] | 180 | .name = "tea6420", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | .driver = &driver, |
| 182 | }; |
| 183 | |
| 184 | static int __init this_module_init(void) |
| 185 | { |
| 186 | return i2c_add_driver(&driver); |
| 187 | } |
| 188 | |
| 189 | static void __exit this_module_exit(void) |
| 190 | { |
| 191 | i2c_del_driver(&driver); |
| 192 | } |
| 193 | |
| 194 | module_init(this_module_init); |
| 195 | module_exit(this_module_exit); |
| 196 | |
| 197 | MODULE_AUTHOR("Michael Hunold <michael@mihu.de>"); |
| 198 | MODULE_DESCRIPTION("tea6420 driver"); |
| 199 | MODULE_LICENSE("GPL"); |