ALSA: firewire-tascam: deleyed registration of sound card
[cascardo/linux.git] / sound / firewire / tascam / tascam.c
1 /*
2  * tascam.c - a part of driver for TASCAM FireWire series
3  *
4  * Copyright (c) 2015 Takashi Sakamoto
5  *
6  * Licensed under the terms of the GNU General Public License, version 2.
7  */
8
9 #include "tascam.h"
10
11 MODULE_DESCRIPTION("TASCAM FireWire series Driver");
12 MODULE_AUTHOR("Takashi Sakamoto <o-takashi@sakamocchi.jp>");
13 MODULE_LICENSE("GPL v2");
14
15 static struct snd_tscm_spec model_specs[] = {
16         {
17                 .name = "FW-1884",
18                 .has_adat = true,
19                 .has_spdif = true,
20                 .pcm_capture_analog_channels = 8,
21                 .pcm_playback_analog_channels = 8,
22                 .midi_capture_ports = 4,
23                 .midi_playback_ports = 4,
24         },
25         {
26                 .name = "FW-1082",
27                 .has_adat = false,
28                 .has_spdif = true,
29                 .pcm_capture_analog_channels = 8,
30                 .pcm_playback_analog_channels = 2,
31                 .midi_capture_ports = 2,
32                 .midi_playback_ports = 2,
33         },
34         {
35                 .name = "FW-1804",
36                 .has_adat = true,
37                 .has_spdif = true,
38                 .pcm_capture_analog_channels = 8,
39                 .pcm_playback_analog_channels = 2,
40                 .midi_capture_ports = 2,
41                 .midi_playback_ports = 4,
42         },
43 };
44
45 static int identify_model(struct snd_tscm *tscm)
46 {
47         struct fw_device *fw_dev = fw_parent_device(tscm->unit);
48         const u32 *config_rom = fw_dev->config_rom;
49         char model[9];
50         unsigned int i;
51         u8 c;
52
53         if (fw_dev->config_rom_length < 30) {
54                 dev_err(&tscm->unit->device,
55                         "Configuration ROM is too short.\n");
56                 return -ENODEV;
57         }
58
59         /* Pick up model name from certain addresses. */
60         for (i = 0; i < 8; i++) {
61                 c = config_rom[28 + i / 4] >> (24 - 8 * (i % 4));
62                 if (c == '\0')
63                         break;
64                 model[i] = c;
65         }
66         model[i] = '\0';
67
68         for (i = 0; i < ARRAY_SIZE(model_specs); i++) {
69                 if (strcmp(model, model_specs[i].name) == 0) {
70                         tscm->spec = &model_specs[i];
71                         break;
72                 }
73         }
74         if (tscm->spec == NULL)
75                 return -ENODEV;
76
77         strcpy(tscm->card->driver, "FW-TASCAM");
78         strcpy(tscm->card->shortname, model);
79         strcpy(tscm->card->mixername, model);
80         snprintf(tscm->card->longname, sizeof(tscm->card->longname),
81                  "TASCAM %s, GUID %08x%08x at %s, S%d", model,
82                  fw_dev->config_rom[3], fw_dev->config_rom[4],
83                  dev_name(&tscm->unit->device), 100 << fw_dev->max_speed);
84
85         return 0;
86 }
87
88 static void tscm_free(struct snd_tscm *tscm)
89 {
90         snd_tscm_transaction_unregister(tscm);
91         snd_tscm_stream_destroy_duplex(tscm);
92
93         fw_unit_put(tscm->unit);
94
95         mutex_destroy(&tscm->mutex);
96 }
97
98 static void tscm_card_free(struct snd_card *card)
99 {
100         tscm_free(card->private_data);
101 }
102
103 static void do_registration(struct work_struct *work)
104 {
105         struct snd_tscm *tscm = container_of(work, struct snd_tscm, dwork.work);
106         int err;
107
108         err = snd_card_new(&tscm->unit->device, -1, NULL, THIS_MODULE, 0,
109                            &tscm->card);
110         if (err < 0)
111                 return;
112
113         err = identify_model(tscm);
114         if (err < 0)
115                 goto error;
116
117         err = snd_tscm_transaction_register(tscm);
118         if (err < 0)
119                 goto error;
120
121         err = snd_tscm_stream_init_duplex(tscm);
122         if (err < 0)
123                 goto error;
124
125         snd_tscm_proc_init(tscm);
126
127         err = snd_tscm_create_pcm_devices(tscm);
128         if (err < 0)
129                 goto error;
130
131         err = snd_tscm_create_midi_devices(tscm);
132         if (err < 0)
133                 goto error;
134
135         err = snd_tscm_create_hwdep_device(tscm);
136         if (err < 0)
137                 goto error;
138
139         err = snd_card_register(tscm->card);
140         if (err < 0)
141                 goto error;
142
143         /*
144          * After registered, tscm instance can be released corresponding to
145          * releasing the sound card instance.
146          */
147         tscm->card->private_free = tscm_card_free;
148         tscm->card->private_data = tscm;
149         tscm->registered = true;
150
151         return;
152 error:
153         snd_tscm_transaction_unregister(tscm);
154         snd_tscm_stream_destroy_duplex(tscm);
155         snd_card_free(tscm->card);
156         dev_info(&tscm->unit->device,
157                  "Sound card registration failed: %d\n", err);
158 }
159
160 static int snd_tscm_probe(struct fw_unit *unit,
161                            const struct ieee1394_device_id *entry)
162 {
163         struct snd_tscm *tscm;
164
165         /* Allocate this independent of sound card instance. */
166         tscm = kzalloc(sizeof(struct snd_tscm), GFP_KERNEL);
167         if (tscm == NULL)
168                 return -ENOMEM;
169
170         /* initialize myself */
171         tscm->unit = fw_unit_get(unit);
172         dev_set_drvdata(&unit->device, tscm);
173
174         mutex_init(&tscm->mutex);
175         spin_lock_init(&tscm->lock);
176         init_waitqueue_head(&tscm->hwdep_wait);
177
178         /* Allocate and register this sound card later. */
179         INIT_DEFERRABLE_WORK(&tscm->dwork, do_registration);
180         snd_fw_schedule_registration(unit, &tscm->dwork);
181
182         return 0;
183 }
184
185 static void snd_tscm_update(struct fw_unit *unit)
186 {
187         struct snd_tscm *tscm = dev_get_drvdata(&unit->device);
188
189         /* Postpone a workqueue for deferred registration. */
190         if (!tscm->registered)
191                 snd_fw_schedule_registration(unit, &tscm->dwork);
192
193         snd_tscm_transaction_reregister(tscm);
194
195         /*
196          * After registration, userspace can start packet streaming, then this
197          * code block works fine.
198          */
199         if (tscm->registered) {
200                 mutex_lock(&tscm->mutex);
201                 snd_tscm_stream_update_duplex(tscm);
202                 mutex_unlock(&tscm->mutex);
203         }
204 }
205
206 static void snd_tscm_remove(struct fw_unit *unit)
207 {
208         struct snd_tscm *tscm = dev_get_drvdata(&unit->device);
209
210         /*
211          * Confirm to stop the work for registration before the sound card is
212          * going to be released. The work is not scheduled again because bus
213          * reset handler is not called anymore.
214          */
215         cancel_delayed_work_sync(&tscm->dwork);
216
217         if (tscm->registered) {
218                 /* No need to wait for releasing card object in this context. */
219                 snd_card_free_when_closed(tscm->card);
220         } else {
221                 /* Don't forget this case. */
222                 tscm_free(tscm);
223         }
224 }
225
226 static const struct ieee1394_device_id snd_tscm_id_table[] = {
227         {
228                 .match_flags = IEEE1394_MATCH_VENDOR_ID |
229                                IEEE1394_MATCH_SPECIFIER_ID,
230                 .vendor_id = 0x00022e,
231                 .specifier_id = 0x00022e,
232         },
233         /* FE-08 requires reverse-engineering because it just has faders. */
234         {}
235 };
236 MODULE_DEVICE_TABLE(ieee1394, snd_tscm_id_table);
237
238 static struct fw_driver tscm_driver = {
239         .driver = {
240                 .owner = THIS_MODULE,
241                 .name = "snd-firewire-tascam",
242                 .bus = &fw_bus_type,
243         },
244         .probe    = snd_tscm_probe,
245         .update   = snd_tscm_update,
246         .remove   = snd_tscm_remove,
247         .id_table = snd_tscm_id_table,
248 };
249
250 static int __init snd_tscm_init(void)
251 {
252         return driver_register(&tscm_driver.driver);
253 }
254
255 static void __exit snd_tscm_exit(void)
256 {
257         driver_unregister(&tscm_driver.driver);
258 }
259
260 module_init(snd_tscm_init);
261 module_exit(snd_tscm_exit);