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/i2c-dev.h>
  27 #include <linux/slab.h>
  28 #include <sound/core.h>
  29 #include "pmac.h"
  30
  31 /*
  32  * we have to keep a static variable here since i2c attach_adapter
  33  * callback cannot pass a private data.
  34  */
  35 static struct pmac_keywest *keywest_ctx;
  36
  37
  38 #define I2C_DRIVERID_KEYWEST    0xFEBA
  39
  40 static int keywest_attach_adapter(struct i2c_adapter *adapter);
  41 static int keywest_detach_client(struct i2c_client *client);
  42
  43 struct i2c_driver keywest_driver = {
  44         .driver = {
  45                 .name = "PMac Keywest Audio",
  46         },
  47         .id = I2C_DRIVERID_KEYWEST,
  48         .attach_adapter = &keywest_attach_adapter,
  49         .detach_client = &keywest_detach_client,
  50 };
  51
  52
  53 #ifndef i2c_device_name
  54 #define i2c_device_name(x)      ((x)->name)
  55 #endif
  56
  57 static int keywest_attach_adapter(struct i2c_adapter *adapter)
  58 {
  59         int err;
  60         struct i2c_client *new_client;
  61
  62         if (! keywest_ctx)
  63                 return -EINVAL;
  64
  65         if (strncmp(i2c_device_name(adapter), "mac-io", 6))
  66                 return 0; /* ignored */
  67
  68         new_client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
  69         if (! new_client)
  70                 return -ENOMEM;
  71
  72         memset(new_client, 0, sizeof(*new_client));
  73         new_client->addr = keywest_ctx->addr;
  74         i2c_set_clientdata(new_client, keywest_ctx);
  75         new_client->adapter = adapter;
  76         new_client->driver = &keywest_driver;
  77         new_client->flags = 0;
  78
  79         strcpy(i2c_device_name(new_client), keywest_ctx->name);
  80         keywest_ctx->client = new_client;
  81
  82         /* Tell the i2c layer a new client has arrived */
  83         if (i2c_attach_client(new_client)) {
  84                 snd_printk(KERN_ERR "tumbler: cannot attach i2c client\n");
  85                 err = -ENODEV;
  86                 goto __err;
  87         }
  88
  89         return 0;
  90
  91  __err:
  92         kfree(new_client);
  93         keywest_ctx->client = NULL;
  94         return err;
  95 }
  96
  97 static int keywest_detach_client(struct i2c_client *client)
  98 {
  99         if (! keywest_ctx)
 100                 return 0;
 101         if (client == keywest_ctx->client)
 102                 keywest_ctx->client = NULL;
 103
 104         i2c_detach_client(client);
 105         kfree(client);
 106         return 0;
 107 }
 108
 109 /* exported */
 110 void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c)
 111 {
 112         if (keywest_ctx && keywest_ctx == i2c) {
 113                 i2c_del_driver(&keywest_driver);
 114                 keywest_ctx = NULL;
 115         }
 116 }
 117
 118 int __init snd_pmac_tumbler_post_init(void)
 119 {
 120         int err;
 121
 122         if ((err = keywest_ctx->init_client(keywest_ctx)) < 0) {
 123                 snd_printk(KERN_ERR "tumbler: %i :cannot initialize the MCS\n", err);
 124                 return err;
 125         }
 126         return 0;
 127 }
 128
 129 /* exported */
 130 int __init snd_pmac_keywest_init(struct pmac_keywest *i2c)
 131 {
 132         int err;
 133
 134         if (keywest_ctx)
 135                 return -EBUSY;
 136
 137         keywest_ctx = i2c;
 138
 139         if ((err = i2c_add_driver(&keywest_driver))) {
 140                 snd_printk(KERN_ERR "cannot register keywest i2c driver\n");
 141                 return err;
 142         }
 143         return 0;
 144 }