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 static int keywest_attach_adapter(struct i2c_adapter *adapter);
  37 static int keywest_detach_client(struct i2c_client *client);
  38
  39 struct i2c_driver keywest_driver = {
  40         .driver = {
  41                 .name = "PMac Keywest Audio",
  42         },
  43         .attach_adapter = &keywest_attach_adapter,
  44         .detach_client = &keywest_detach_client,
  45 };
  46
  47
  48 #ifndef i2c_device_name
  49 #define i2c_device_name(x)      ((x)->name)
  50 #endif
  51
  52 static int keywest_attach_adapter(struct i2c_adapter *adapter)
  53 {
  54         int err;
  55         struct i2c_client *new_client;
  56
  57         if (! keywest_ctx)
  58                 return -EINVAL;
  59
  60         if (strncmp(i2c_device_name(adapter), "mac-io", 6))
  61                 return 0; /* ignored */
  62
  63         new_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
  64         if (! new_client)
  65                 return -ENOMEM;
  66
  67         new_client->addr = keywest_ctx->addr;
  68         i2c_set_clientdata(new_client, keywest_ctx);
  69         new_client->adapter = adapter;
  70         new_client->driver = &keywest_driver;
  71         new_client->flags = 0;
  72
  73         strcpy(i2c_device_name(new_client), keywest_ctx->name);
  74         keywest_ctx->client = new_client;
  75
  76         /* Tell the i2c layer a new client has arrived */
  77         if (i2c_attach_client(new_client)) {
  78                 snd_printk(KERN_ERR "tumbler: cannot attach i2c client\n");
  79                 err = -ENODEV;
  80                 goto __err;
  81         }
  82
  83         return 0;
  84
  85  __err:
  86         kfree(new_client);
  87         keywest_ctx->client = NULL;
  88         return err;
  89 }
  90
  91 static int keywest_detach_client(struct i2c_client *client)
  92 {
  93         if (! keywest_ctx)
  94                 return 0;
  95         if (client == keywest_ctx->client)
  96                 keywest_ctx->client = NULL;
  97
  98         i2c_detach_client(client);
  99         kfree(client);
 100         return 0;
 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 }