1 /*
2 * Stanton Control System 1 MIDI driver
3 *
4 * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
5 * Licensed under the terms of the GNU General Public License, version 2.
6 */
7
8 #include <linux/device.h>
9 #include <linux/firewire.h>
10 #include <linux/firewire-constants.h>
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/slab.h>
15 #include <linux/string.h>
16 #include <linux/wait.h>
17 #include <sound/core.h>
18 #include <sound/initval.h>
19 #include <sound/rawmidi.h>
20 #include "lib.h"
21
22 #define OUI_STANTON 0x001260
23 #define MODEL_SCS_1M 0x001000
24 #define MODEL_SCS_1D 0x002000
25
26 #define HSS1394_ADDRESS 0xc007dedadadaULL
27 #define HSS1394_MAX_PACKET_SIZE 64
28
29 #define HSS1394_TAG_USER_DATA 0x00
30 #define HSS1394_TAG_CHANGE_ADDRESS 0xf1
31
32 struct scs {
33 struct snd_card *card;
34 struct fw_unit *unit;
35 struct fw_address_handler hss_handler;
36 struct fw_transaction transaction;
37 bool transaction_running;
38 bool output_idle;
39 u8 output_status;
40 u8 output_bytes;
41 bool output_escaped;
42 bool output_escape_high_nibble;
43 u8 input_escape_count;
44 struct snd_rawmidi_substream *output;
45 struct snd_rawmidi_substream *input;
46 struct tasklet_struct tasklet;
47 wait_queue_head_t idle_wait;
48 u8 *buffer;
49 };
50
51 static const u8 sysex_escape_prefix[] = {
52 0xf0, /* SysEx begin */
53 0x00, 0x01, 0x60, /* Stanton DJ */
54 0x48, 0x53, 0x53, /* "HSS" */
55 };
56
scs_output_open(struct snd_rawmidi_substream * stream)57 static int scs_output_open(struct snd_rawmidi_substream *stream)
58 {
59 struct scs *scs = stream->rmidi->private_data;
60
61 scs->output_status = 0;
62 scs->output_bytes = 1;
63 scs->output_escaped = false;
64
65 return 0;
66 }
67
scs_output_close(struct snd_rawmidi_substream * stream)68 static int scs_output_close(struct snd_rawmidi_substream *stream)
69 {
70 return 0;
71 }
72
scs_output_trigger(struct snd_rawmidi_substream * stream,int up)73 static void scs_output_trigger(struct snd_rawmidi_substream *stream, int up)
74 {
75 struct scs *scs = stream->rmidi->private_data;
76
77 ACCESS_ONCE(scs->output) = up ? stream : NULL;
78 if (up) {
79 scs->output_idle = false;
80 tasklet_schedule(&scs->tasklet);
81 }
82 }
83
scs_write_callback(struct fw_card * card,int rcode,void * data,size_t length,void * callback_data)84 static void scs_write_callback(struct fw_card *card, int rcode,
85 void *data, size_t length, void *callback_data)
86 {
87 struct scs *scs = callback_data;
88
89 if (rcode == RCODE_GENERATION) {
90 /* TODO: retry this packet */
91 }
92
93 scs->transaction_running = false;
94 tasklet_schedule(&scs->tasklet);
95 }
96
is_valid_running_status(u8 status)97 static bool is_valid_running_status(u8 status)
98 {
99 return status >= 0x80 && status <= 0xef;
100 }
101
is_one_byte_cmd(u8 status)102 static bool is_one_byte_cmd(u8 status)
103 {
104 return status == 0xf6 ||
105 status >= 0xf8;
106 }
107
is_two_bytes_cmd(u8 status)108 static bool is_two_bytes_cmd(u8 status)
109 {
110 return (status >= 0xc0 && status <= 0xdf) ||
111 status == 0xf1 ||
112 status == 0xf3;
113 }
114
is_three_bytes_cmd(u8 status)115 static bool is_three_bytes_cmd(u8 status)
116 {
117 return (status >= 0x80 && status <= 0xbf) ||
118 (status >= 0xe0 && status <= 0xef) ||
119 status == 0xf2;
120 }
121
is_invalid_cmd(u8 status)122 static bool is_invalid_cmd(u8 status)
123 {
124 return status == 0xf4 ||
125 status == 0xf5 ||
126 status == 0xf9 ||
127 status == 0xfd;
128 }
129
scs_output_tasklet(unsigned long data)130 static void scs_output_tasklet(unsigned long data)
131 {
132 struct scs *scs = (void *)data;
133 struct snd_rawmidi_substream *stream;
134 unsigned int i;
135 u8 byte;
136 struct fw_device *dev;
137 int generation;
138
139 if (scs->transaction_running)
140 return;
141
142 stream = ACCESS_ONCE(scs->output);
143 if (!stream) {
144 scs->output_idle = true;
145 wake_up(&scs->idle_wait);
146 return;
147 }
148
149 i = scs->output_bytes;
150 for (;;) {
151 if (snd_rawmidi_transmit(stream, &byte, 1) != 1) {
152 scs->output_bytes = i;
153 scs->output_idle = true;
154 wake_up(&scs->idle_wait);
155 return;
156 }
157 /*
158 * Convert from real MIDI to what I think the device expects (no
159 * running status, one command per packet, unescaped SysExs).
160 */
161 if (scs->output_escaped && byte < 0x80) {
162 if (scs->output_escape_high_nibble) {
163 if (i < HSS1394_MAX_PACKET_SIZE) {
164 scs->buffer[i] = byte << 4;
165 scs->output_escape_high_nibble = false;
166 }
167 } else {
168 scs->buffer[i++] |= byte & 0x0f;
169 scs->output_escape_high_nibble = true;
170 }
171 } else if (byte < 0x80) {
172 if (i == 1) {
173 if (!is_valid_running_status(scs->output_status))
174 continue;
175 scs->buffer[0] = HSS1394_TAG_USER_DATA;
176 scs->buffer[i++] = scs->output_status;
177 }
178 scs->buffer[i++] = byte;
179 if ((i == 3 && is_two_bytes_cmd(scs->output_status)) ||
180 (i == 4 && is_three_bytes_cmd(scs->output_status)))
181 break;
182 if (i == 1 + ARRAY_SIZE(sysex_escape_prefix) &&
183 !memcmp(scs->buffer + 1, sysex_escape_prefix,
184 ARRAY_SIZE(sysex_escape_prefix))) {
185 scs->output_escaped = true;
186 scs->output_escape_high_nibble = true;
187 i = 0;
188 }
189 if (i >= HSS1394_MAX_PACKET_SIZE)
190 i = 1;
191 } else if (byte == 0xf7) {
192 if (scs->output_escaped) {
193 if (i >= 1 && scs->output_escape_high_nibble &&
194 scs->buffer[0] != HSS1394_TAG_CHANGE_ADDRESS)
195 break;
196 } else {
197 if (i > 1 && scs->output_status == 0xf0) {
198 scs->buffer[i++] = 0xf7;
199 break;
200 }
201 }
202 i = 1;
203 scs->output_escaped = false;
204 } else if (!is_invalid_cmd(byte) &&
205 byte < 0xf8) {
206 i = 1;
207 scs->buffer[0] = HSS1394_TAG_USER_DATA;
208 scs->buffer[i++] = byte;
209 scs->output_status = byte;
210 scs->output_escaped = false;
211 if (is_one_byte_cmd(byte))
212 break;
213 }
214 }
215 scs->output_bytes = 1;
216 scs->output_escaped = false;
217
218 scs->transaction_running = true;
219 dev = fw_parent_device(scs->unit);
220 generation = dev->generation;
221 smp_rmb(); /* node_id vs. generation */
222 fw_send_request(dev->card, &scs->transaction, TCODE_WRITE_BLOCK_REQUEST,
223 dev->node_id, generation, dev->max_speed,
224 HSS1394_ADDRESS, scs->buffer, i,
225 scs_write_callback, scs);
226 }
227
scs_output_drain(struct snd_rawmidi_substream * stream)228 static void scs_output_drain(struct snd_rawmidi_substream *stream)
229 {
230 struct scs *scs = stream->rmidi->private_data;
231
232 wait_event(scs->idle_wait, scs->output_idle);
233 }
234
235 static struct snd_rawmidi_ops output_ops = {
236 .open = scs_output_open,
237 .close = scs_output_close,
238 .trigger = scs_output_trigger,
239 .drain = scs_output_drain,
240 };
241
scs_input_open(struct snd_rawmidi_substream * stream)242 static int scs_input_open(struct snd_rawmidi_substream *stream)
243 {
244 struct scs *scs = stream->rmidi->private_data;
245
246 scs->input_escape_count = 0;
247
248 return 0;
249 }
250
scs_input_close(struct snd_rawmidi_substream * stream)251 static int scs_input_close(struct snd_rawmidi_substream *stream)
252 {
253 return 0;
254 }
255
scs_input_trigger(struct snd_rawmidi_substream * stream,int up)256 static void scs_input_trigger(struct snd_rawmidi_substream *stream, int up)
257 {
258 struct scs *scs = stream->rmidi->private_data;
259
260 ACCESS_ONCE(scs->input) = up ? stream : NULL;
261 }
262
scs_input_escaped_byte(struct snd_rawmidi_substream * stream,u8 byte)263 static void scs_input_escaped_byte(struct snd_rawmidi_substream *stream,
264 u8 byte)
265 {
266 u8 nibbles[2];
267
268 nibbles[0] = byte >> 4;
269 nibbles[1] = byte & 0x0f;
270 snd_rawmidi_receive(stream, nibbles, 2);
271 }
272
scs_input_midi_byte(struct scs * scs,struct snd_rawmidi_substream * stream,u8 byte)273 static void scs_input_midi_byte(struct scs *scs,
274 struct snd_rawmidi_substream *stream,
275 u8 byte)
276 {
277 if (scs->input_escape_count > 0) {
278 scs_input_escaped_byte(stream, byte);
279 scs->input_escape_count--;
280 if (scs->input_escape_count == 0)
281 snd_rawmidi_receive(stream, (const u8[]) { 0xf7 }, 1);
282 } else if (byte == 0xf9) {
283 snd_rawmidi_receive(stream, sysex_escape_prefix,
284 ARRAY_SIZE(sysex_escape_prefix));
285 scs_input_escaped_byte(stream, 0x00);
286 scs_input_escaped_byte(stream, 0xf9);
287 scs->input_escape_count = 3;
288 } else {
289 snd_rawmidi_receive(stream, &byte, 1);
290 }
291 }
292
scs_input_packet(struct scs * scs,struct snd_rawmidi_substream * stream,const u8 * data,unsigned int bytes)293 static void scs_input_packet(struct scs *scs,
294 struct snd_rawmidi_substream *stream,
295 const u8 *data, unsigned int bytes)
296 {
297 unsigned int i;
298
299 if (data[0] == HSS1394_TAG_USER_DATA) {
300 for (i = 1; i < bytes; ++i)
301 scs_input_midi_byte(scs, stream, data[i]);
302 } else {
303 snd_rawmidi_receive(stream, sysex_escape_prefix,
304 ARRAY_SIZE(sysex_escape_prefix));
305 for (i = 0; i < bytes; ++i)
306 scs_input_escaped_byte(stream, data[i]);
307 snd_rawmidi_receive(stream, (const u8[]) { 0xf7 }, 1);
308 }
309 }
310
311 static struct snd_rawmidi_ops input_ops = {
312 .open = scs_input_open,
313 .close = scs_input_close,
314 .trigger = scs_input_trigger,
315 };
316
scs_create_midi(struct scs * scs)317 static int scs_create_midi(struct scs *scs)
318 {
319 struct snd_rawmidi *rmidi;
320 int err;
321
322 err = snd_rawmidi_new(scs->card, "SCS.1x", 0, 1, 1, &rmidi);
323 if (err < 0)
324 return err;
325 snprintf(rmidi->name, sizeof(rmidi->name),
326 "%s MIDI", scs->card->shortname);
327 rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
328 SNDRV_RAWMIDI_INFO_INPUT |
329 SNDRV_RAWMIDI_INFO_DUPLEX;
330 rmidi->private_data = scs;
331 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &output_ops);
332 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &input_ops);
333
334 return 0;
335 }
336
handle_hss(struct fw_card * card,struct fw_request * request,int tcode,int destination,int source,int generation,unsigned long long offset,void * data,size_t length,void * callback_data)337 static void handle_hss(struct fw_card *card, struct fw_request *request,
338 int tcode, int destination, int source, int generation,
339 unsigned long long offset, void *data, size_t length,
340 void *callback_data)
341 {
342 struct scs *scs = callback_data;
343 struct snd_rawmidi_substream *stream;
344
345 if (offset != scs->hss_handler.offset) {
346 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
347 return;
348 }
349 if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
350 tcode != TCODE_WRITE_BLOCK_REQUEST) {
351 fw_send_response(card, request, RCODE_TYPE_ERROR);
352 return;
353 }
354
355 if (length >= 1) {
356 stream = ACCESS_ONCE(scs->input);
357 if (stream)
358 scs_input_packet(scs, stream, data, length);
359 }
360
361 fw_send_response(card, request, RCODE_COMPLETE);
362 }
363
scs_init_hss_address(struct scs * scs)364 static int scs_init_hss_address(struct scs *scs)
365 {
366 __be64 data;
367 int err;
368
369 data = cpu_to_be64(((u64)HSS1394_TAG_CHANGE_ADDRESS << 56) |
370 scs->hss_handler.offset);
371 err = snd_fw_transaction(scs->unit, TCODE_WRITE_BLOCK_REQUEST,
372 HSS1394_ADDRESS, &data, 8);
373 if (err < 0)
374 dev_err(&scs->unit->device, "HSS1394 communication failed\n");
375
376 return err;
377 }
378
scs_card_free(struct snd_card * card)379 static void scs_card_free(struct snd_card *card)
380 {
381 struct scs *scs = card->private_data;
382
383 fw_core_remove_address_handler(&scs->hss_handler);
384 kfree(scs->buffer);
385 }
386
scs_probe(struct device * unit_dev)387 static int scs_probe(struct device *unit_dev)
388 {
389 struct fw_unit *unit = fw_unit(unit_dev);
390 struct fw_device *fw_dev = fw_parent_device(unit);
391 struct snd_card *card;
392 struct scs *scs;
393 int err;
394
395 err = snd_card_create(-16, NULL, THIS_MODULE, sizeof(*scs), &card);
396 if (err < 0)
397 return err;
398 snd_card_set_dev(card, unit_dev);
399
400 scs = card->private_data;
401 scs->card = card;
402 scs->unit = unit;
403 tasklet_init(&scs->tasklet, scs_output_tasklet, (unsigned long)scs);
404 init_waitqueue_head(&scs->idle_wait);
405 scs->output_idle = true;
406
407 scs->buffer = kmalloc(HSS1394_MAX_PACKET_SIZE, GFP_KERNEL);
408 if (!scs->buffer)
409 goto err_card;
410
411 scs->hss_handler.length = HSS1394_MAX_PACKET_SIZE;
412 scs->hss_handler.address_callback = handle_hss;
413 scs->hss_handler.callback_data = scs;
414 err = fw_core_add_address_handler(&scs->hss_handler,
415 &fw_high_memory_region);
416 if (err < 0)
417 goto err_buffer;
418
419 card->private_free = scs_card_free;
420
421 strcpy(card->driver, "SCS.1x");
422 strcpy(card->shortname, "SCS.1x");
423 fw_csr_string(unit->directory, CSR_MODEL,
424 card->shortname, sizeof(card->shortname));
425 snprintf(card->longname, sizeof(card->longname),
426 "Stanton DJ %s (GUID %08x%08x) at %s, S%d",
427 card->shortname, fw_dev->config_rom[3], fw_dev->config_rom[4],
428 dev_name(&unit->device), 100 << fw_dev->max_speed);
429 strcpy(card->mixername, card->shortname);
430
431 err = scs_init_hss_address(scs);
432 if (err < 0)
433 goto err_card;
434
435 err = scs_create_midi(scs);
436 if (err < 0)
437 goto err_card;
438
439 err = snd_card_register(card);
440 if (err < 0)
441 goto err_card;
442
443 dev_set_drvdata(unit_dev, scs);
444
445 return 0;
446
447 err_buffer:
448 kfree(scs->buffer);
449 err_card:
450 snd_card_free(card);
451 return err;
452 }
453
scs_remove(struct device * dev)454 static int scs_remove(struct device *dev)
455 {
456 struct scs *scs = dev_get_drvdata(dev);
457
458 snd_card_disconnect(scs->card);
459
460 ACCESS_ONCE(scs->output) = NULL;
461 ACCESS_ONCE(scs->input) = NULL;
462
463 wait_event(scs->idle_wait, scs->output_idle);
464
465 tasklet_kill(&scs->tasklet);
466
467 snd_card_free_when_closed(scs->card);
468
469 return 0;
470 }
471
scs_update(struct fw_unit * unit)472 static void scs_update(struct fw_unit *unit)
473 {
474 struct scs *scs = dev_get_drvdata(&unit->device);
475 __be64 data;
476
477 data = cpu_to_be64(((u64)HSS1394_TAG_CHANGE_ADDRESS << 56) |
478 scs->hss_handler.offset);
479 snd_fw_transaction(scs->unit, TCODE_WRITE_BLOCK_REQUEST,
480 HSS1394_ADDRESS, &data, 8);
481 }
482
483 static const struct ieee1394_device_id scs_id_table[] = {
484 {
485 .match_flags = IEEE1394_MATCH_VENDOR_ID |
486 IEEE1394_MATCH_MODEL_ID,
487 .vendor_id = OUI_STANTON,
488 .model_id = MODEL_SCS_1M,
489 },
490 {
491 .match_flags = IEEE1394_MATCH_VENDOR_ID |
492 IEEE1394_MATCH_MODEL_ID,
493 .vendor_id = OUI_STANTON,
494 .model_id = MODEL_SCS_1D,
495 },
496 {}
497 };
498 MODULE_DEVICE_TABLE(ieee1394, scs_id_table);
499
500 MODULE_DESCRIPTION("SCS.1x MIDI driver");
501 MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
502 MODULE_LICENSE("GPL v2");
503
504 static struct fw_driver scs_driver = {
505 .driver = {
506 .owner = THIS_MODULE,
507 .name = KBUILD_MODNAME,
508 .bus = &fw_bus_type,
509 .probe = scs_probe,
510 .remove = scs_remove,
511 },
512 .update = scs_update,
513 .id_table = scs_id_table,
514 };
515
alsa_scs1x_init(void)516 static int __init alsa_scs1x_init(void)
517 {
518 return driver_register(&scs_driver.driver);
519 }
520
alsa_scs1x_exit(void)521 static void __exit alsa_scs1x_exit(void)
522 {
523 driver_unregister(&scs_driver.driver);
524 }
525
526 module_init(alsa_scs1x_init);
527 module_exit(alsa_scs1x_exit);
528