1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * common keywest i2c layer
4 *
5 * Copyright (c) by Takashi Iwai <[email protected]>
6 */
7
8
9 #include <linux/init.h>
10 #include <linux/i2c.h>
11 #include <linux/delay.h>
12 #include <linux/module.h>
13 #include <sound/core.h>
14 #include "pmac.h"
15
16 static struct pmac_keywest *keywest_ctx;
17 static bool keywest_probed;
18
keywest_probe(struct i2c_client * client)19 static int keywest_probe(struct i2c_client *client)
20 {
21 keywest_probed = true;
22 /* If instantiated via i2c-powermac, we still need to set the client */
23 if (!keywest_ctx->client)
24 keywest_ctx->client = client;
25 i2c_set_clientdata(client, keywest_ctx);
26 return 0;
27 }
28
29 /*
30 * This is kind of a hack, best would be to turn powermac to fixed i2c
31 * bus numbers and declare the sound device as part of platform
32 * initialization
33 */
keywest_attach_adapter(struct i2c_adapter * adapter)34 static int keywest_attach_adapter(struct i2c_adapter *adapter)
35 {
36 struct i2c_board_info info;
37 struct i2c_client *client;
38
39 if (! keywest_ctx)
40 return -EINVAL;
41
42 if (strncmp(adapter->name, "mac-io", 6))
43 return -EINVAL; /* ignored */
44
45 memset(&info, 0, sizeof(struct i2c_board_info));
46 strscpy(info.type, "keywest", I2C_NAME_SIZE);
47 info.addr = keywest_ctx->addr;
48 client = i2c_new_client_device(adapter, &info);
49 if (IS_ERR(client))
50 return PTR_ERR(client);
51 keywest_ctx->client = client;
52
53 /*
54 * We know the driver is already loaded, so the device should be
55 * already bound. If not it means binding failed, and then there
56 * is no point in keeping the device instantiated.
57 */
58 if (!keywest_ctx->client->dev.driver) {
59 i2c_unregister_device(keywest_ctx->client);
60 keywest_ctx->client = NULL;
61 return -ENODEV;
62 }
63
64 return 0;
65 }
66
keywest_remove(struct i2c_client * client)67 static void keywest_remove(struct i2c_client *client)
68 {
69 if (! keywest_ctx)
70 return;
71 if (client == keywest_ctx->client)
72 keywest_ctx->client = NULL;
73 }
74
75
76 static const struct i2c_device_id keywest_i2c_id[] = {
77 { "MAC,tas3004" }, /* instantiated by i2c-powermac */
78 { "keywest" }, /* instantiated by us if needed */
79 { }
80 };
81 MODULE_DEVICE_TABLE(i2c, keywest_i2c_id);
82
83 static struct i2c_driver keywest_driver = {
84 .driver = {
85 .name = "PMac Keywest Audio",
86 },
87 .probe = keywest_probe,
88 .remove = keywest_remove,
89 .id_table = keywest_i2c_id,
90 };
91
92 /* exported */
snd_pmac_keywest_cleanup(struct pmac_keywest * i2c)93 void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c)
94 {
95 if (keywest_ctx && keywest_ctx == i2c) {
96 i2c_unregister_device(keywest_ctx->client);
97 i2c_del_driver(&keywest_driver);
98 keywest_ctx = NULL;
99 }
100 }
101
snd_pmac_tumbler_post_init(void)102 int snd_pmac_tumbler_post_init(void)
103 {
104 int err;
105
106 if (!keywest_ctx || !keywest_ctx->client)
107 return -ENXIO;
108
109 err = keywest_ctx->init_client(keywest_ctx);
110 if (err < 0) {
111 dev_err(&keywest_ctx->client->dev,
112 "tumbler: %i :cannot initialize the MCS\n", err);
113 return err;
114 }
115 return 0;
116 }
117
118 /* exported */
snd_pmac_keywest_init(struct pmac_keywest * i2c)119 int snd_pmac_keywest_init(struct pmac_keywest *i2c)
120 {
121 struct i2c_adapter *adap;
122 int err, i = 0;
123
124 if (keywest_ctx)
125 return -EBUSY;
126
127 adap = i2c_get_adapter(0);
128 if (!adap)
129 return -EPROBE_DEFER;
130
131 keywest_ctx = i2c;
132
133 err = i2c_add_driver(&keywest_driver);
134 if (err) {
135 dev_err(&i2c->client->dev, "cannot register keywest i2c driver\n");
136 i2c_put_adapter(adap);
137 return err;
138 }
139
140 /* There was already a device from i2c-powermac. Great, let's return */
141 if (keywest_probed)
142 return 0;
143
144 /* We assume Macs have consecutive I2C bus numbers starting at 0 */
145 while (adap) {
146 /* Scan for devices to be bound to */
147 err = keywest_attach_adapter(adap);
148 if (!err)
149 return 0;
150 i2c_put_adapter(adap);
151 adap = i2c_get_adapter(++i);
152 }
153
154 return -ENODEV;
155 }
156