1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * common keywest i2c layer |
4 | * |
5 | * Copyright (c) by Takashi Iwai <tiwai@suse.de> |
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 | |
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, data: 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 | */ |
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(p: info.type, q: "keywest" , I2C_NAME_SIZE); |
47 | info.addr = keywest_ctx->addr; |
48 | client = i2c_new_client_device(adap: adapter, info: &info); |
49 | if (IS_ERR(ptr: client)) |
50 | return PTR_ERR(ptr: 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(client: keywest_ctx->client); |
60 | keywest_ctx->client = NULL; |
61 | return -ENODEV; |
62 | } |
63 | |
64 | /* |
65 | * Let i2c-core delete that device on driver removal. |
66 | * This is safe because i2c-core holds the core_lock mutex for us. |
67 | */ |
68 | list_add_tail(new: &keywest_ctx->client->detected, |
69 | head: &to_i2c_driver(keywest_ctx->client->dev.driver)->clients); |
70 | return 0; |
71 | } |
72 | |
73 | static void keywest_remove(struct i2c_client *client) |
74 | { |
75 | if (! keywest_ctx) |
76 | return; |
77 | if (client == keywest_ctx->client) |
78 | keywest_ctx->client = NULL; |
79 | } |
80 | |
81 | |
82 | static const struct i2c_device_id keywest_i2c_id[] = { |
83 | { "MAC,tas3004" , 0 }, /* instantiated by i2c-powermac */ |
84 | { "keywest" , 0 }, /* instantiated by us if needed */ |
85 | { } |
86 | }; |
87 | MODULE_DEVICE_TABLE(i2c, keywest_i2c_id); |
88 | |
89 | static struct i2c_driver keywest_driver = { |
90 | .driver = { |
91 | .name = "PMac Keywest Audio" , |
92 | }, |
93 | .probe = keywest_probe, |
94 | .remove = keywest_remove, |
95 | .id_table = keywest_i2c_id, |
96 | }; |
97 | |
98 | /* exported */ |
99 | void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c) |
100 | { |
101 | if (keywest_ctx && keywest_ctx == i2c) { |
102 | i2c_del_driver(driver: &keywest_driver); |
103 | keywest_ctx = NULL; |
104 | } |
105 | } |
106 | |
107 | int snd_pmac_tumbler_post_init(void) |
108 | { |
109 | int err; |
110 | |
111 | if (!keywest_ctx || !keywest_ctx->client) |
112 | return -ENXIO; |
113 | |
114 | err = keywest_ctx->init_client(keywest_ctx); |
115 | if (err < 0) { |
116 | snd_printk(KERN_ERR "tumbler: %i :cannot initialize the MCS\n" , err); |
117 | return err; |
118 | } |
119 | return 0; |
120 | } |
121 | |
122 | /* exported */ |
123 | int snd_pmac_keywest_init(struct pmac_keywest *i2c) |
124 | { |
125 | struct i2c_adapter *adap; |
126 | int err, i = 0; |
127 | |
128 | if (keywest_ctx) |
129 | return -EBUSY; |
130 | |
131 | adap = i2c_get_adapter(nr: 0); |
132 | if (!adap) |
133 | return -EPROBE_DEFER; |
134 | |
135 | keywest_ctx = i2c; |
136 | |
137 | err = i2c_add_driver(&keywest_driver); |
138 | if (err) { |
139 | snd_printk(KERN_ERR "cannot register keywest i2c driver\n" ); |
140 | i2c_put_adapter(adap); |
141 | return err; |
142 | } |
143 | |
144 | /* There was already a device from i2c-powermac. Great, let's return */ |
145 | if (keywest_probed) |
146 | return 0; |
147 | |
148 | /* We assume Macs have consecutive I2C bus numbers starting at 0 */ |
149 | while (adap) { |
150 | /* Scan for devices to be bound to */ |
151 | err = keywest_attach_adapter(adapter: adap); |
152 | if (!err) |
153 | return 0; |
154 | i2c_put_adapter(adap); |
155 | adap = i2c_get_adapter(nr: ++i); |
156 | } |
157 | |
158 | return -ENODEV; |
159 | } |
160 | |