summaryrefslogtreecommitdiff
path: root/sound/ppc/keywest.c
blob: 4373615f13e297f73cc356dfb39fcd2e0fecdd4c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/*
 * common keywest i2c layer
 *
 * Copyright (c) by Takashi Iwai <tiwai@suse.de>
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */


#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <sound/core.h>
#include "pmac.h"

/*
 * we have to keep a static variable here since i2c attach_adapter
 * callback cannot pass a private data.
 */
static struct pmac_keywest *keywest_ctx;

static bool keywest_probed;

static int keywest_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	keywest_probed = true;
	/* If instantiated via i2c-powermac, we still need to set the client */
	if (!keywest_ctx->client)
		keywest_ctx->client = client;
	i2c_set_clientdata(client, keywest_ctx);
	return 0;
}

/*
 * This is kind of a hack, best would be to turn powermac to fixed i2c
 * bus numbers and declare the sound device as part of platform
 * initialization
 */
static int keywest_attach_adapter(struct i2c_adapter *adapter)
{
	struct i2c_board_info info;

	if (! keywest_ctx)
		return -EINVAL;

	if (strncmp(adapter->name, "mac-io", 6))
		return -EINVAL; /* ignored */

	memset(&info, 0, sizeof(struct i2c_board_info));
	strlcpy(info.type, "keywest", I2C_NAME_SIZE);
	info.addr = keywest_ctx->addr;
	keywest_ctx->client = i2c_new_device(adapter, &info);
	if (!keywest_ctx->client)
		return -ENODEV;
	/*
	 * We know the driver is already loaded, so the device should be
	 * already bound. If not it means binding failed, and then there
	 * is no point in keeping the device instantiated.
	 */
	if (!keywest_ctx->client->dev.driver) {
		i2c_unregister_device(keywest_ctx->client);
		keywest_ctx->client = NULL;
		return -ENODEV;
	}
	
	/*
	 * Let i2c-core delete that device on driver removal.
	 * This is safe because i2c-core holds the core_lock mutex for us.
	 */
	list_add_tail(&keywest_ctx->client->detected,
		      &to_i2c_driver(keywest_ctx->client->dev.driver)->clients);
	return 0;
}

static int keywest_remove(struct i2c_client *client)
{
	if (! keywest_ctx)
		return 0;
	if (client == keywest_ctx->client)
		keywest_ctx->client = NULL;

	return 0;
}


static const struct i2c_device_id keywest_i2c_id[] = {
	{ "MAC,tas3004", 0 },		/* instantiated by i2c-powermac */
	{ "keywest", 0 },		/* instantiated by us if needed */
	{ }
};
MODULE_DEVICE_TABLE(i2c, keywest_i2c_id);

static struct i2c_driver keywest_driver = {
	.driver = {
		.name = "PMac Keywest Audio",
	},
	.probe = keywest_probe,
	.remove = keywest_remove,
	.id_table = keywest_i2c_id,
};

/* exported */
void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c)
{
	if (keywest_ctx && keywest_ctx == i2c) {
		i2c_del_driver(&keywest_driver);
		keywest_ctx = NULL;
	}
}

int snd_pmac_tumbler_post_init(void)
{
	int err;
	
	if (!keywest_ctx || !keywest_ctx->client)
		return -ENXIO;

	if ((err = keywest_ctx->init_client(keywest_ctx)) < 0) {
		snd_printk(KERN_ERR "tumbler: %i :cannot initialize the MCS\n", err);
		return err;
	}
	return 0;
}

/* exported */
int snd_pmac_keywest_init(struct pmac_keywest *i2c)
{
	struct i2c_adapter *adap;
	int err, i = 0;

	if (keywest_ctx)
		return -EBUSY;

	adap = i2c_get_adapter(0);
	if (!adap)
		return -EPROBE_DEFER;

	keywest_ctx = i2c;

	if ((err = i2c_add_driver(&keywest_driver))) {
		snd_printk(KERN_ERR "cannot register keywest i2c driver\n");
		i2c_put_adapter(adap);
		return err;
	}

	/* There was already a device from i2c-powermac. Great, let's return */
	if (keywest_probed)
		return 0;

	/* We assume Macs have consecutive I2C bus numbers starting at 0 */
	while (adap) {
		/* Scan for devices to be bound to */
		err = keywest_attach_adapter(adap);
		if (!err)
			return 0;
		i2c_put_adapter(adap);
		adap = i2c_get_adapter(++i);
	}

	return -ENODEV;
}