LXR linux/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 */
  33static struct pmac_keywest *keywest_ctx;
  34
  35
  36static int keywest_attach_adapter(struct i2c_adapter *adapter);
  37static int keywest_detach_client(struct i2c_client *client);
  38
  39struct 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
  52static 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
  91static 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 */
 104void 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
 112int __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 */
 127int __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}
 142