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