xref: /openbmc/linux/sound/ppc/keywest.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
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  */
35 static pmac_keywest_t *keywest_ctx;
36 
37 
38 #define I2C_DRIVERID_KEYWEST	0xFEBA
39 
40 static int keywest_attach_adapter(struct i2c_adapter *adapter);
41 static int keywest_detach_client(struct i2c_client *client);
42 
43 struct 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 
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(pmac_keywest_t *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(pmac_keywest_t *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 }
144