LXR linux-bk/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 */
  35static pmac_keywest_t *keywest_ctx;
  36
  37
  38#define I2C_DRIVERID_KEYWEST    0xFEBA
  39
  40static int keywest_attach_adapter(struct i2c_adapter *adapter);
  41static int keywest_detach_client(struct i2c_client *client);
  42
  43struct i2c_driver keywest_driver = {  
  44        .name = "PMac Keywest Audio",
  45        .id = I2C_DRIVERID_KEYWEST,
  46        .flags = I2C_DF_NOTIFY,
  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
  56static 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
  80        new_client->id = keywest_ctx->id++; /* Automatically unique */
  81        keywest_ctx->client = new_client;
  82        
  83        /* Tell the i2c layer a new client has arrived */
  84        if (i2c_attach_client(new_client)) {
  85                snd_printk(KERN_ERR "tumbler: cannot attach i2c client\n");
  86                err = -ENODEV;
  87                goto __err;
  88        }
  89
  90        return 0;
  91
  92 __err:
  93        kfree(new_client);
  94        keywest_ctx->client = NULL;
  95        return err;
  96}
  97
  98static int keywest_detach_client(struct i2c_client *client)
  99{
 100        if (! keywest_ctx)
 101                return 0;
 102        if (client == keywest_ctx->client)
 103                keywest_ctx->client = NULL;
 104
 105        i2c_detach_client(client);
 106        kfree(client);
 107        return 0;
 108}
 109
 110/* exported */
 111void snd_pmac_keywest_cleanup(pmac_keywest_t *i2c)
 112{
 113        if (keywest_ctx && keywest_ctx == i2c) {
 114                i2c_del_driver(&keywest_driver);
 115                keywest_ctx = NULL;
 116        }
 117}
 118
 119int __init snd_pmac_tumbler_post_init(void)
 120{
 121        int err;
 122        
 123        if ((err = keywest_ctx->init_client(keywest_ctx)) < 0) {
 124                snd_printk(KERN_ERR "tumbler: %i :cannot initialize the MCS\n", err);
 125                return err;
 126        }
 127        return 0;
 128}
 129
 130/* exported */
 131int __init snd_pmac_keywest_init(pmac_keywest_t *i2c)
 132{
 133        int err;
 134
 135        if (keywest_ctx)
 136                return -EBUSY;
 137
 138        keywest_ctx = i2c;
 139
 140        if ((err = i2c_add_driver(&keywest_driver))) {
 141                snd_printk(KERN_ERR "cannot register keywest i2c driver\n");
 142                return err;
 143        }
 144        return 0;
 145}
 146