xref: /openbmc/linux/sound/ppc/keywest.c (revision 78c99ba1)
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  */
33 static struct pmac_keywest *keywest_ctx;
34 
35 
36 #ifndef i2c_device_name
37 #define i2c_device_name(x)	((x)->name)
38 #endif
39 
40 static int keywest_probe(struct i2c_client *client,
41 			 const struct i2c_device_id *id)
42 {
43 	i2c_set_clientdata(client, keywest_ctx);
44 	return 0;
45 }
46 
47 /*
48  * This is kind of a hack, best would be to turn powermac to fixed i2c
49  * bus numbers and declare the sound device as part of platform
50  * initialization
51  */
52 static int keywest_attach_adapter(struct i2c_adapter *adapter)
53 {
54 	struct i2c_board_info info;
55 
56 	if (! keywest_ctx)
57 		return -EINVAL;
58 
59 	if (strncmp(i2c_device_name(adapter), "mac-io", 6))
60 		return 0; /* ignored */
61 
62 	memset(&info, 0, sizeof(struct i2c_board_info));
63 	strlcpy(info.type, "keywest", I2C_NAME_SIZE);
64 	info.addr = keywest_ctx->addr;
65 	keywest_ctx->client = i2c_new_device(adapter, &info);
66 
67 	/*
68 	 * Let i2c-core delete that device on driver removal.
69 	 * This is safe because i2c-core holds the core_lock mutex for us.
70 	 */
71 	list_add_tail(&keywest_ctx->client->detected,
72 		      &keywest_ctx->client->driver->clients);
73 	return 0;
74 }
75 
76 static int keywest_remove(struct i2c_client *client)
77 {
78 	i2c_set_clientdata(client, NULL);
79 	if (! keywest_ctx)
80 		return 0;
81 	if (client == keywest_ctx->client)
82 		keywest_ctx->client = NULL;
83 
84 	return 0;
85 }
86 
87 
88 static const struct i2c_device_id keywest_i2c_id[] = {
89 	{ "keywest", 0 },
90 	{ }
91 };
92 
93 struct i2c_driver keywest_driver = {
94 	.driver = {
95 		.name = "PMac Keywest Audio",
96 	},
97 	.attach_adapter = keywest_attach_adapter,
98 	.probe = keywest_probe,
99 	.remove = keywest_remove,
100 	.id_table = keywest_i2c_id,
101 };
102 
103 /* exported */
104 void 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 
112 int __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 */
127 int __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