1 /* 2 tea6420 - i2c-driver for the tea6420 by SGS Thomson 3 4 Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de> 5 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl> 6 7 The tea6420 is a bus controlled audio-matrix with 5 stereo inputs, 8 4 stereo outputs and gain control for each output. 9 It is cascadable, i.e. it can be found at the addresses 0x98 10 and 0x9a on the i2c-bus. 11 12 For detailed informations download the specifications directly 13 from SGS Thomson at http://www.st.com 14 15 This program is free software; you can redistribute it and/or modify 16 it under the terms of the GNU General Public License as published by 17 the Free Software Foundation; either version 2 of the License, or 18 (at your option) any later version. 19 20 This program is distributed in the hope that it will be useful, 21 but WITHOUT ANY WARRANTY; without even the implied warranty of 22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 23 GNU General Public License for more details. 24 25 You should have received a copy of the GNU General Public License 26 along with this program; if not, write to the Free Software 27 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 28 */ 29 30 31 #include <linux/module.h> 32 #include <linux/ioctl.h> 33 #include <linux/slab.h> 34 #include <linux/i2c.h> 35 #include <media/v4l2-device.h> 36 #include <media/v4l2-chip-ident.h> 37 #include "tea6420.h" 38 39 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>"); 40 MODULE_DESCRIPTION("tea6420 driver"); 41 MODULE_LICENSE("GPL"); 42 43 static int debug; 44 module_param(debug, int, 0644); 45 46 MODULE_PARM_DESC(debug, "Debug level (0-1)"); 47 48 49 /* make a connection between the input 'i' and the output 'o' 50 with gain 'g' (note: i = 6 means 'mute') */ 51 static int tea6420_s_routing(struct v4l2_subdev *sd, 52 u32 i, u32 o, u32 config) 53 { 54 struct i2c_client *client = v4l2_get_subdevdata(sd); 55 int g = (o >> 4) & 0xf; 56 u8 byte; 57 int ret; 58 59 o &= 0xf; 60 v4l2_dbg(1, debug, sd, "i=%d, o=%d, g=%d\n", i, o, g); 61 62 /* check if the parameters are valid */ 63 if (i < 1 || i > 6 || o < 1 || o > 4 || g < 0 || g > 6 || g % 2 != 0) 64 return -EINVAL; 65 66 byte = ((o - 1) << 5); 67 byte |= (i - 1); 68 69 /* to understand this, have a look at the tea6420-specs (p.5) */ 70 switch (g) { 71 case 0: 72 byte |= (3 << 3); 73 break; 74 case 2: 75 byte |= (2 << 3); 76 break; 77 case 4: 78 byte |= (1 << 3); 79 break; 80 case 6: 81 break; 82 } 83 84 ret = i2c_smbus_write_byte(client, byte); 85 if (ret) { 86 v4l2_dbg(1, debug, sd, 87 "i2c_smbus_write_byte() failed, ret:%d\n", ret); 88 return -EIO; 89 } 90 return 0; 91 } 92 93 static int tea6420_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip) 94 { 95 struct i2c_client *client = v4l2_get_subdevdata(sd); 96 97 return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_TEA6420, 0); 98 } 99 100 /* ----------------------------------------------------------------------- */ 101 102 static const struct v4l2_subdev_core_ops tea6420_core_ops = { 103 .g_chip_ident = tea6420_g_chip_ident, 104 }; 105 106 static const struct v4l2_subdev_audio_ops tea6420_audio_ops = { 107 .s_routing = tea6420_s_routing, 108 }; 109 110 static const struct v4l2_subdev_ops tea6420_ops = { 111 .core = &tea6420_core_ops, 112 .audio = &tea6420_audio_ops, 113 }; 114 115 static int tea6420_probe(struct i2c_client *client, 116 const struct i2c_device_id *id) 117 { 118 struct v4l2_subdev *sd; 119 int err, i; 120 121 /* let's see whether this adapter can support what we need */ 122 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE)) 123 return -EIO; 124 125 v4l_info(client, "chip found @ 0x%x (%s)\n", 126 client->addr << 1, client->adapter->name); 127 128 sd = kzalloc(sizeof(struct v4l2_subdev), GFP_KERNEL); 129 if (sd == NULL) 130 return -ENOMEM; 131 v4l2_i2c_subdev_init(sd, client, &tea6420_ops); 132 133 /* set initial values: set "mute"-input to all outputs at gain 0 */ 134 err = 0; 135 for (i = 1; i < 5; i++) 136 err += tea6420_s_routing(sd, 6, i, 0); 137 if (err) { 138 v4l_dbg(1, debug, client, "could not initialize tea6420\n"); 139 return -ENODEV; 140 } 141 return 0; 142 } 143 144 static int tea6420_remove(struct i2c_client *client) 145 { 146 struct v4l2_subdev *sd = i2c_get_clientdata(client); 147 148 v4l2_device_unregister_subdev(sd); 149 kfree(sd); 150 return 0; 151 } 152 153 static const struct i2c_device_id tea6420_id[] = { 154 { "tea6420", 0 }, 155 { } 156 }; 157 MODULE_DEVICE_TABLE(i2c, tea6420_id); 158 159 static struct i2c_driver tea6420_driver = { 160 .driver = { 161 .owner = THIS_MODULE, 162 .name = "tea6420", 163 }, 164 .probe = tea6420_probe, 165 .remove = tea6420_remove, 166 .id_table = tea6420_id, 167 }; 168 169 module_i2c_driver(tea6420_driver); 170