1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* ALSA sequencer binding for UMP device */
3
4 #include <linux/init.h>
5 #include <linux/slab.h>
6 #include <linux/errno.h>
7 #include <linux/mutex.h>
8 #include <linux/string.h>
9 #include <linux/module.h>
10 #include <asm/byteorder.h>
11 #include <sound/core.h>
12 #include <sound/ump.h>
13 #include <sound/seq_kernel.h>
14 #include <sound/seq_device.h>
15 #include "seq_clientmgr.h"
16 #include "seq_system.h"
17
18 struct seq_ump_client;
19 struct seq_ump_group;
20
21 enum {
22 STR_IN = SNDRV_RAWMIDI_STREAM_INPUT,
23 STR_OUT = SNDRV_RAWMIDI_STREAM_OUTPUT
24 };
25
26 /* context for UMP input parsing, per EP */
27 struct seq_ump_input_buffer {
28 unsigned char len; /* total length in words */
29 unsigned char pending; /* pending words */
30 unsigned char type; /* parsed UMP packet type */
31 unsigned char group; /* parsed UMP packet group */
32 u32 buf[4]; /* incoming UMP packet */
33 };
34
35 /* sequencer client, per UMP EP (rawmidi) */
36 struct seq_ump_client {
37 struct snd_ump_endpoint *ump; /* assigned endpoint */
38 int seq_client; /* sequencer client id */
39 int opened[2]; /* current opens for each direction */
40 struct snd_rawmidi_file out_rfile; /* rawmidi for output */
41 struct seq_ump_input_buffer input; /* input parser context */
42 void *ump_info[SNDRV_UMP_MAX_BLOCKS + 1]; /* shadow of seq client ump_info */
43 struct work_struct group_notify_work; /* FB change notification */
44 };
45
46 /* number of 32bit words for each UMP message type */
47 static unsigned char ump_packet_words[0x10] = {
48 1, 1, 1, 2, 2, 4, 1, 1, 2, 2, 2, 3, 3, 4, 4, 4
49 };
50
51 /* conversion between UMP group and seq port;
52 * assume the port number is equal with UMP group number (1-based)
53 */
ump_group_to_seq_port(unsigned char group)54 static unsigned char ump_group_to_seq_port(unsigned char group)
55 {
56 return group + 1;
57 }
58
59 /* process the incoming rawmidi stream */
seq_ump_input_receive(struct snd_ump_endpoint * ump,const u32 * val,int words)60 static void seq_ump_input_receive(struct snd_ump_endpoint *ump,
61 const u32 *val, int words)
62 {
63 struct seq_ump_client *client = ump->seq_client;
64 struct snd_seq_ump_event ev = {};
65
66 if (!client->opened[STR_IN])
67 return;
68
69 if (ump_is_groupless_msg(ump_message_type(*val)))
70 ev.source.port = 0; /* UMP EP port */
71 else
72 ev.source.port = ump_group_to_seq_port(ump_message_group(*val));
73 ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
74 ev.flags = SNDRV_SEQ_EVENT_UMP;
75 memcpy(ev.ump, val, words << 2);
76 snd_seq_kernel_client_dispatch(client->seq_client,
77 (struct snd_seq_event *)&ev,
78 true, 0);
79 }
80
81 /* process an input sequencer event; only deal with UMP types */
seq_ump_process_event(struct snd_seq_event * ev,int direct,void * private_data,int atomic,int hop)82 static int seq_ump_process_event(struct snd_seq_event *ev, int direct,
83 void *private_data, int atomic, int hop)
84 {
85 struct seq_ump_client *client = private_data;
86 struct snd_rawmidi_substream *substream;
87 struct snd_seq_ump_event *ump_ev;
88 unsigned char type;
89 int len;
90
91 substream = client->out_rfile.output;
92 if (!substream)
93 return -ENODEV;
94 if (!snd_seq_ev_is_ump(ev))
95 return 0; /* invalid event, skip */
96 ump_ev = (struct snd_seq_ump_event *)ev;
97 type = ump_message_type(ump_ev->ump[0]);
98 len = ump_packet_words[type];
99 if (len > 4)
100 return 0; // invalid - skip
101 snd_rawmidi_kernel_write(substream, ev->data.raw8.d, len << 2);
102 return 0;
103 }
104
105 /* open the rawmidi */
seq_ump_client_open(struct seq_ump_client * client,int dir)106 static int seq_ump_client_open(struct seq_ump_client *client, int dir)
107 {
108 struct snd_ump_endpoint *ump = client->ump;
109 int err;
110
111 guard(mutex)(&ump->open_mutex);
112 if (dir == STR_OUT && !client->opened[dir]) {
113 err = snd_rawmidi_kernel_open(&ump->core, 0,
114 SNDRV_RAWMIDI_LFLG_OUTPUT |
115 SNDRV_RAWMIDI_LFLG_APPEND,
116 &client->out_rfile);
117 if (err < 0)
118 return err;
119 }
120 client->opened[dir]++;
121 return 0;
122 }
123
124 /* close the rawmidi */
seq_ump_client_close(struct seq_ump_client * client,int dir)125 static int seq_ump_client_close(struct seq_ump_client *client, int dir)
126 {
127 struct snd_ump_endpoint *ump = client->ump;
128
129 guard(mutex)(&ump->open_mutex);
130 if (!--client->opened[dir])
131 if (dir == STR_OUT)
132 snd_rawmidi_kernel_release(&client->out_rfile);
133 return 0;
134 }
135
136 /* sequencer subscription ops for each client */
seq_ump_subscribe(void * pdata,struct snd_seq_port_subscribe * info)137 static int seq_ump_subscribe(void *pdata, struct snd_seq_port_subscribe *info)
138 {
139 struct seq_ump_client *client = pdata;
140
141 return seq_ump_client_open(client, STR_IN);
142 }
143
seq_ump_unsubscribe(void * pdata,struct snd_seq_port_subscribe * info)144 static int seq_ump_unsubscribe(void *pdata, struct snd_seq_port_subscribe *info)
145 {
146 struct seq_ump_client *client = pdata;
147
148 return seq_ump_client_close(client, STR_IN);
149 }
150
seq_ump_use(void * pdata,struct snd_seq_port_subscribe * info)151 static int seq_ump_use(void *pdata, struct snd_seq_port_subscribe *info)
152 {
153 struct seq_ump_client *client = pdata;
154
155 return seq_ump_client_open(client, STR_OUT);
156 }
157
seq_ump_unuse(void * pdata,struct snd_seq_port_subscribe * info)158 static int seq_ump_unuse(void *pdata, struct snd_seq_port_subscribe *info)
159 {
160 struct seq_ump_client *client = pdata;
161
162 return seq_ump_client_close(client, STR_OUT);
163 }
164
165 /* fill port_info from the given UMP EP and group info */
fill_port_info(struct snd_seq_port_info * port,struct seq_ump_client * client,struct snd_ump_group * group)166 static void fill_port_info(struct snd_seq_port_info *port,
167 struct seq_ump_client *client,
168 struct snd_ump_group *group)
169 {
170 unsigned int rawmidi_info = client->ump->core.info_flags;
171
172 port->addr.client = client->seq_client;
173 port->addr.port = ump_group_to_seq_port(group->group);
174 port->capability = 0;
175 if (rawmidi_info & SNDRV_RAWMIDI_INFO_OUTPUT)
176 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE |
177 SNDRV_SEQ_PORT_CAP_SYNC_WRITE |
178 SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
179 if (rawmidi_info & SNDRV_RAWMIDI_INFO_INPUT)
180 port->capability |= SNDRV_SEQ_PORT_CAP_READ |
181 SNDRV_SEQ_PORT_CAP_SYNC_READ |
182 SNDRV_SEQ_PORT_CAP_SUBS_READ;
183 if (rawmidi_info & SNDRV_RAWMIDI_INFO_DUPLEX)
184 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
185 if (group->dir_bits & (1 << STR_IN))
186 port->direction |= SNDRV_SEQ_PORT_DIR_INPUT;
187 if (group->dir_bits & (1 << STR_OUT))
188 port->direction |= SNDRV_SEQ_PORT_DIR_OUTPUT;
189 port->ump_group = group->group + 1;
190 if (!group->active)
191 port->capability |= SNDRV_SEQ_PORT_CAP_INACTIVE;
192 if (group->is_midi1)
193 port->flags |= SNDRV_SEQ_PORT_FLG_IS_MIDI1;
194 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC |
195 SNDRV_SEQ_PORT_TYPE_MIDI_UMP |
196 SNDRV_SEQ_PORT_TYPE_HARDWARE |
197 SNDRV_SEQ_PORT_TYPE_PORT;
198 port->midi_channels = 16;
199 if (*group->name)
200 snprintf(port->name, sizeof(port->name), "Group %d (%.53s)",
201 group->group + 1, group->name);
202 else
203 sprintf(port->name, "Group %d", group->group + 1);
204 }
205
206 /* skip non-existing group for static blocks */
skip_group(struct seq_ump_client * client,struct snd_ump_group * group)207 static bool skip_group(struct seq_ump_client *client, struct snd_ump_group *group)
208 {
209 return !group->valid &&
210 (client->ump->info.flags & SNDRV_UMP_EP_INFO_STATIC_BLOCKS);
211 }
212
213 /* create a new sequencer port per UMP group */
seq_ump_group_init(struct seq_ump_client * client,int group_index)214 static int seq_ump_group_init(struct seq_ump_client *client, int group_index)
215 {
216 struct snd_ump_group *group = &client->ump->groups[group_index];
217 struct snd_seq_port_info *port __free(kfree) = NULL;
218 struct snd_seq_port_callback pcallbacks;
219
220 if (skip_group(client, group))
221 return 0;
222
223 port = kzalloc(sizeof(*port), GFP_KERNEL);
224 if (!port)
225 return -ENOMEM;
226
227 fill_port_info(port, client, group);
228 port->flags |= SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
229 memset(&pcallbacks, 0, sizeof(pcallbacks));
230 pcallbacks.owner = THIS_MODULE;
231 pcallbacks.private_data = client;
232 pcallbacks.subscribe = seq_ump_subscribe;
233 pcallbacks.unsubscribe = seq_ump_unsubscribe;
234 pcallbacks.use = seq_ump_use;
235 pcallbacks.unuse = seq_ump_unuse;
236 pcallbacks.event_input = seq_ump_process_event;
237 port->kernel = &pcallbacks;
238 return snd_seq_kernel_client_ctl(client->seq_client,
239 SNDRV_SEQ_IOCTL_CREATE_PORT,
240 port);
241 }
242
243 /* update the sequencer ports; called from notify_fb_change callback */
update_port_infos(struct seq_ump_client * client)244 static void update_port_infos(struct seq_ump_client *client)
245 {
246 struct snd_seq_port_info *old __free(kfree) = NULL;
247 struct snd_seq_port_info *new __free(kfree) = NULL;
248 int i, err;
249
250 old = kzalloc(sizeof(*old), GFP_KERNEL);
251 new = kzalloc(sizeof(*new), GFP_KERNEL);
252 if (!old || !new)
253 return;
254
255 for (i = 0; i < SNDRV_UMP_MAX_GROUPS; i++) {
256 if (skip_group(client, &client->ump->groups[i]))
257 continue;
258
259 old->addr.client = client->seq_client;
260 old->addr.port = ump_group_to_seq_port(i);
261 err = snd_seq_kernel_client_ctl(client->seq_client,
262 SNDRV_SEQ_IOCTL_GET_PORT_INFO,
263 old);
264 if (err < 0)
265 continue;
266 fill_port_info(new, client, &client->ump->groups[i]);
267 if (old->capability == new->capability &&
268 !strcmp(old->name, new->name))
269 continue;
270 err = snd_seq_kernel_client_ctl(client->seq_client,
271 SNDRV_SEQ_IOCTL_SET_PORT_INFO,
272 new);
273 if (err < 0)
274 continue;
275 }
276 }
277
278 /* create a UMP Endpoint port */
create_ump_endpoint_port(struct seq_ump_client * client)279 static int create_ump_endpoint_port(struct seq_ump_client *client)
280 {
281 struct snd_seq_port_info *port __free(kfree) = NULL;
282 struct snd_seq_port_callback pcallbacks;
283 unsigned int rawmidi_info = client->ump->core.info_flags;
284 int err;
285
286 port = kzalloc(sizeof(*port), GFP_KERNEL);
287 if (!port)
288 return -ENOMEM;
289
290 port->addr.client = client->seq_client;
291 port->addr.port = 0; /* fixed */
292 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
293 port->capability = SNDRV_SEQ_PORT_CAP_UMP_ENDPOINT;
294 if (rawmidi_info & SNDRV_RAWMIDI_INFO_INPUT) {
295 port->capability |= SNDRV_SEQ_PORT_CAP_READ |
296 SNDRV_SEQ_PORT_CAP_SYNC_READ |
297 SNDRV_SEQ_PORT_CAP_SUBS_READ;
298 port->direction |= SNDRV_SEQ_PORT_DIR_INPUT;
299 }
300 if (rawmidi_info & SNDRV_RAWMIDI_INFO_OUTPUT) {
301 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE |
302 SNDRV_SEQ_PORT_CAP_SYNC_WRITE |
303 SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
304 port->direction |= SNDRV_SEQ_PORT_DIR_OUTPUT;
305 }
306 if (rawmidi_info & SNDRV_RAWMIDI_INFO_DUPLEX)
307 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
308 port->ump_group = 0; /* no associated group, no conversion */
309 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_UMP |
310 SNDRV_SEQ_PORT_TYPE_HARDWARE |
311 SNDRV_SEQ_PORT_TYPE_PORT;
312 port->midi_channels = 16;
313 strcpy(port->name, "MIDI 2.0");
314 memset(&pcallbacks, 0, sizeof(pcallbacks));
315 pcallbacks.owner = THIS_MODULE;
316 pcallbacks.private_data = client;
317 if (rawmidi_info & SNDRV_RAWMIDI_INFO_INPUT) {
318 pcallbacks.subscribe = seq_ump_subscribe;
319 pcallbacks.unsubscribe = seq_ump_unsubscribe;
320 }
321 if (rawmidi_info & SNDRV_RAWMIDI_INFO_OUTPUT) {
322 pcallbacks.use = seq_ump_use;
323 pcallbacks.unuse = seq_ump_unuse;
324 pcallbacks.event_input = seq_ump_process_event;
325 }
326 port->kernel = &pcallbacks;
327 err = snd_seq_kernel_client_ctl(client->seq_client,
328 SNDRV_SEQ_IOCTL_CREATE_PORT,
329 port);
330 return err;
331 }
332
333 /* release the client resources */
seq_ump_client_free(struct seq_ump_client * client)334 static void seq_ump_client_free(struct seq_ump_client *client)
335 {
336 cancel_work_sync(&client->group_notify_work);
337
338 if (client->seq_client >= 0)
339 snd_seq_delete_kernel_client(client->seq_client);
340
341 client->ump->seq_ops = NULL;
342 client->ump->seq_client = NULL;
343
344 kfree(client);
345 }
346
347 /* update the MIDI version for the given client */
setup_client_midi_version(struct seq_ump_client * client)348 static void setup_client_midi_version(struct seq_ump_client *client)
349 {
350 struct snd_seq_client *cptr;
351
352 cptr = snd_seq_kernel_client_get(client->seq_client);
353 if (!cptr)
354 return;
355 if (client->ump->info.protocol & SNDRV_UMP_EP_INFO_PROTO_MIDI2)
356 cptr->midi_version = SNDRV_SEQ_CLIENT_UMP_MIDI_2_0;
357 else
358 cptr->midi_version = SNDRV_SEQ_CLIENT_UMP_MIDI_1_0;
359 snd_seq_kernel_client_put(cptr);
360 }
361
362 /* set up client's group_filter bitmap */
setup_client_group_filter(struct seq_ump_client * client)363 static void setup_client_group_filter(struct seq_ump_client *client)
364 {
365 struct snd_seq_client *cptr;
366 unsigned int filter;
367 int p;
368
369 cptr = snd_seq_kernel_client_get(client->seq_client);
370 if (!cptr)
371 return;
372 filter = ~(1U << 0); /* always allow groupless messages */
373 for (p = 0; p < SNDRV_UMP_MAX_GROUPS; p++) {
374 if (client->ump->groups[p].active)
375 filter &= ~(1U << (p + 1));
376 }
377 cptr->group_filter = filter;
378 snd_seq_kernel_client_put(cptr);
379 }
380
381 /* UMP group change notification */
handle_group_notify(struct work_struct * work)382 static void handle_group_notify(struct work_struct *work)
383 {
384 struct seq_ump_client *client =
385 container_of(work, struct seq_ump_client, group_notify_work);
386
387 update_port_infos(client);
388 setup_client_group_filter(client);
389 }
390
391 /* UMP EP change notification */
seq_ump_notify_ep_change(struct snd_ump_endpoint * ump)392 static int seq_ump_notify_ep_change(struct snd_ump_endpoint *ump)
393 {
394 struct seq_ump_client *client = ump->seq_client;
395 struct snd_seq_client *cptr;
396 int client_id;
397
398 if (!client)
399 return -ENODEV;
400 client_id = client->seq_client;
401 cptr = snd_seq_kernel_client_get(client_id);
402 if (!cptr)
403 return -ENODEV;
404
405 snd_seq_system_ump_notify(client_id, 0, SNDRV_SEQ_EVENT_UMP_EP_CHANGE,
406 true);
407
408 /* update sequencer client name if needed */
409 if (*ump->core.name && strcmp(ump->core.name, cptr->name)) {
410 strscpy(cptr->name, ump->core.name, sizeof(cptr->name));
411 snd_seq_system_client_ev_client_change(client_id);
412 }
413
414 snd_seq_kernel_client_put(cptr);
415 return 0;
416 }
417
418 /* UMP FB change notification */
seq_ump_notify_fb_change(struct snd_ump_endpoint * ump,struct snd_ump_block * fb)419 static int seq_ump_notify_fb_change(struct snd_ump_endpoint *ump,
420 struct snd_ump_block *fb)
421 {
422 struct seq_ump_client *client = ump->seq_client;
423
424 if (!client)
425 return -ENODEV;
426 schedule_work(&client->group_notify_work);
427 snd_seq_system_ump_notify(client->seq_client, fb->info.block_id,
428 SNDRV_SEQ_EVENT_UMP_BLOCK_CHANGE,
429 true);
430 return 0;
431 }
432
433 /* UMP protocol change notification; just update the midi_version field */
seq_ump_switch_protocol(struct snd_ump_endpoint * ump)434 static int seq_ump_switch_protocol(struct snd_ump_endpoint *ump)
435 {
436 struct seq_ump_client *client = ump->seq_client;
437
438 if (!client)
439 return -ENODEV;
440 setup_client_midi_version(client);
441 snd_seq_system_ump_notify(client->seq_client, 0,
442 SNDRV_SEQ_EVENT_UMP_EP_CHANGE,
443 true);
444 return 0;
445 }
446
447 static const struct snd_seq_ump_ops seq_ump_ops = {
448 .input_receive = seq_ump_input_receive,
449 .notify_ep_change = seq_ump_notify_ep_change,
450 .notify_fb_change = seq_ump_notify_fb_change,
451 .switch_protocol = seq_ump_switch_protocol,
452 };
453
454 /* create a sequencer client and ports for the given UMP endpoint */
snd_seq_ump_probe(struct device * _dev)455 static int snd_seq_ump_probe(struct device *_dev)
456 {
457 struct snd_seq_device *dev = to_seq_dev(_dev);
458 struct snd_ump_endpoint *ump = dev->private_data;
459 struct snd_card *card = dev->card;
460 struct seq_ump_client *client;
461 struct snd_ump_block *fb;
462 struct snd_seq_client *cptr;
463 int p, err;
464
465 client = kzalloc(sizeof(*client), GFP_KERNEL);
466 if (!client)
467 return -ENOMEM;
468
469 INIT_WORK(&client->group_notify_work, handle_group_notify);
470 client->ump = ump;
471
472 client->seq_client =
473 snd_seq_create_kernel_client(card, ump->core.device,
474 ump->core.name);
475 if (client->seq_client < 0) {
476 err = client->seq_client;
477 goto error;
478 }
479
480 client->ump_info[0] = &ump->info;
481 list_for_each_entry(fb, &ump->block_list, list)
482 client->ump_info[fb->info.block_id + 1] = &fb->info;
483
484 setup_client_midi_version(client);
485
486 for (p = 0; p < SNDRV_UMP_MAX_GROUPS; p++) {
487 err = seq_ump_group_init(client, p);
488 if (err < 0)
489 goto error;
490 }
491
492 setup_client_group_filter(client);
493
494 err = create_ump_endpoint_port(client);
495 if (err < 0)
496 goto error;
497
498 cptr = snd_seq_kernel_client_get(client->seq_client);
499 if (!cptr) {
500 err = -EINVAL;
501 goto error;
502 }
503 cptr->ump_info = client->ump_info;
504 snd_seq_kernel_client_put(cptr);
505
506 ump->seq_client = client;
507 ump->seq_ops = &seq_ump_ops;
508 return 0;
509
510 error:
511 seq_ump_client_free(client);
512 return err;
513 }
514
515 /* remove a sequencer client */
snd_seq_ump_remove(struct device * _dev)516 static int snd_seq_ump_remove(struct device *_dev)
517 {
518 struct snd_seq_device *dev = to_seq_dev(_dev);
519 struct snd_ump_endpoint *ump = dev->private_data;
520
521 if (ump->seq_client)
522 seq_ump_client_free(ump->seq_client);
523 return 0;
524 }
525
526 static struct snd_seq_driver seq_ump_driver = {
527 .driver = {
528 .name = KBUILD_MODNAME,
529 .probe = snd_seq_ump_probe,
530 .remove = snd_seq_ump_remove,
531 },
532 .id = SNDRV_SEQ_DEV_ID_UMP,
533 .argsize = 0,
534 };
535
536 module_snd_seq_driver(seq_ump_driver);
537
538 MODULE_DESCRIPTION("ALSA sequencer client for UMP rawmidi");
539 MODULE_LICENSE("GPL");
540