sound/ppc/keywest.c

   1 /*
   2  * common keywest i2c layer
   3  *
   4  * Copyright (c) by Takashi Iwai <tiwai@suse.de>
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  */
  20
  21
  22 #include <linux/init.h>
  23 #include <linux/i2c.h>
  24 #include <linux/delay.h>
  25 #include <linux/slab.h>
  26 #include <sound/core.h>
  27 #include "pmac.h"
  28
  29 /*
  30  * we have to keep a static variable here since i2c attach_adapter
  31  * callback cannot pass a private data.
  32  */
  33 static struct pmac_keywest *keywest_ctx;
  34
  35
  36 #ifndef i2c_device_name
  37 #define i2c_device_name(x)      ((x)->name)
  38 #endif
  39
  40 static int keywest_probe(struct i2c_client *client,
  41                          const struct i2c_device_id *id)
  42 {
  43         i2c_set_clientdata(client, keywest_ctx);
  44         return 0;
  45 }
  46
  47 /*
  48  * This is kind of a hack, best would be to turn powermac to fixed i2c
  49  * bus numbers and declare the sound device as part of platform
  50  * initialization
  51  */
  52 static int keywest_attach_adapter(struct i2c_adapter *adapter)
  53 {
  54         struct i2c_board_info info;
  55
  56         if (! keywest_ctx)
  57                 return -EINVAL;
  58
  59         if (strncmp(i2c_device_name(adapter), "mac-io", 6))
  60                 return 0; /* ignored */
  61
  62         memset(&info, 0, sizeof(struct i2c_board_info));
  63         strlcpy(info.type, "keywest", I2C_NAME_SIZE);
  64         info.addr = keywest_ctx->addr;
  65         keywest_ctx->client = i2c_new_device(adapter, &info);
  66
  67         /*
  68          * Let i2c-core delete that device on driver removal.
  69          * This is safe because i2c-core holds the core_lock mutex for us.
  70          */
  71         list_add_tail(&keywest_ctx->client->detected,
  72                       &keywest_ctx->client->driver->clients);
  73         return 0;
  74 }
  75
  76 static int keywest_remove(struct i2c_client *client)
  77 {
  78         i2c_set_clientdata(client, NULL);
  79         if (! keywest_ctx)
  80                 return 0;
  81         if (client == keywest_ctx->client)
  82                 keywest_ctx->client = NULL;
  83
  84         return 0;
  85 }
  86
  87
  88 static const struct i2c_device_id keywest_i2c_id[] = {
  89         { "keywest", 0 },
  90         { }
  91 };
  92
  93 struct i2c_driver keywest_driver = {
  94         .driver = {
  95                 .name = "PMac Keywest Audio",
  96         },
  97         .attach_adapter = keywest_attach_adapter,
  98         .probe = keywest_probe,
  99         .remove = keywest_remove,
 100         .id_table = keywest_i2c_id,
 101 };
 102
 103 /* exported */
 104 void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c)
 105 {
 106         if (keywest_ctx && keywest_ctx == i2c) {
 107                 i2c_del_driver(&keywest_driver);
 108                 keywest_ctx = NULL;
 109         }
 110 }
 111
 112 int __init snd_pmac_tumbler_post_init(void)
 113 {
 114         int err;
 115
 116         if (!keywest_ctx || !keywest_ctx->client)
 117                 return -ENXIO;
 118
 119         if ((err = keywest_ctx->init_client(keywest_ctx)) < 0) {
 120                 snd_printk(KERN_ERR "tumbler: %i :cannot initialize the MCS\n", err);
 121                 return err;
 122         }
 123         return 0;
 124 }
 125
 126 /* exported */
 127 int __init snd_pmac_keywest_init(struct pmac_keywest *i2c)
 128 {
 129         int err;
 130
 131         if (keywest_ctx)
 132                 return -EBUSY;
 133
 134         keywest_ctx = i2c;
 135
 136         if ((err = i2c_add_driver(&keywest_driver))) {
 137                 snd_printk(KERN_ERR "cannot register keywest i2c driver\n");
 138                 return err;
 139         }
 140         return 0;
 141 }