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 <sound/driver.h>
  23 #include <linux/init.h>
  24 #include <linux/i2c.h>
  25 #include <linux/delay.h>
  26 #include <linux/slab.h>
  27 #include <sound/core.h>
  28 #include "pmac.h"
  29
  30 /*
  31  * we have to keep a static variable here since i2c attach_adapter
  32  * callback cannot pass a private data.
  33  */
  34 static struct pmac_keywest *keywest_ctx;
  35
  36
  37 static int keywest_attach_adapter(struct i2c_adapter *adapter);
  38 static int keywest_detach_client(struct i2c_client *client);
  39
  40 struct i2c_driver keywest_driver = {
  41         .driver = {
  42                 .name = "PMac Keywest Audio",
  43         },
  44         .attach_adapter = &keywest_attach_adapter,
  45         .detach_client = &keywest_detach_client,
  46 };
  47
  48
  49 #ifndef i2c_device_name
  50 #define i2c_device_name(x)      ((x)->name)
  51 #endif
  52
  53 static int keywest_attach_adapter(struct i2c_adapter *adapter)
  54 {
  55         int err;
  56         struct i2c_client *new_client;
  57
  58         if (! keywest_ctx)
  59                 return -EINVAL;
  60
  61         if (strncmp(i2c_device_name(adapter), "mac-io", 6))
  62                 return 0; /* ignored */
  63
  64         new_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
  65         if (! new_client)
  66                 return -ENOMEM;
  67
  68         new_client->addr = keywest_ctx->addr;
  69         i2c_set_clientdata(new_client, keywest_ctx);
  70         new_client->adapter = adapter;
  71         new_client->driver = &keywest_driver;
  72         new_client->flags = 0;
  73
  74         strcpy(i2c_device_name(new_client), keywest_ctx->name);
  75         keywest_ctx->client = new_client;
  76
  77         /* Tell the i2c layer a new client has arrived */
  78         if (i2c_attach_client(new_client)) {
  79                 snd_printk(KERN_ERR "tumbler: cannot attach i2c client\n");
  80                 err = -ENODEV;
  81                 goto __err;
  82         }
  83
  84         return 0;
  85
  86  __err:
  87         kfree(new_client);
  88         keywest_ctx->client = NULL;
  89         return err;
  90 }
  91
  92 static int keywest_detach_client(struct i2c_client *client)
  93 {
  94         if (! keywest_ctx)
  95                 return 0;
  96         if (client == keywest_ctx->client)
  97                 keywest_ctx->client = NULL;
  98
  99         i2c_detach_client(client);
 100         kfree(client);
 101         return 0;
 102 }
 103
 104 /* exported */
 105 void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c)
 106 {
 107         if (keywest_ctx && keywest_ctx == i2c) {
 108                 i2c_del_driver(&keywest_driver);
 109                 keywest_ctx = NULL;
 110         }
 111 }
 112
 113 int __init snd_pmac_tumbler_post_init(void)
 114 {
 115         int err;
 116
 117         if (!keywest_ctx || !keywest_ctx->client)
 118                 return -ENXIO;
 119
 120         if ((err = keywest_ctx->init_client(keywest_ctx)) < 0) {
 121                 snd_printk(KERN_ERR "tumbler: %i :cannot initialize the MCS\n", err);
 122                 return err;
 123         }
 124         return 0;
 125 }
 126
 127 /* exported */
 128 int __init snd_pmac_keywest_init(struct pmac_keywest *i2c)
 129 {
 130         int err;
 131
 132         if (keywest_ctx)
 133                 return -EBUSY;
 134
 135         keywest_ctx = i2c;
 136
 137         if ((err = i2c_add_driver(&keywest_driver))) {
 138                 snd_printk(KERN_ERR "cannot register keywest i2c driver\n");
 139                 return err;
 140         }
 141         return 0;
 142 }