xref: /openbmc/linux/sound/core/seq/seq_ump_client.c (revision eb9fe179)
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 /* object per UMP group; corresponding to a sequencer port */
27 struct seq_ump_group {
28 	int group;			/* group index (0-based) */
29 	unsigned int dir_bits;		/* directions */
30 	bool active;			/* activeness */
31 	char name[64];			/* seq port name */
32 };
33 
34 /* context for UMP input parsing, per EP */
35 struct seq_ump_input_buffer {
36 	unsigned char len;		/* total length in words */
37 	unsigned char pending;		/* pending words */
38 	unsigned char type;		/* parsed UMP packet type */
39 	unsigned char group;		/* parsed UMP packet group */
40 	u32 buf[4];			/* incoming UMP packet */
41 };
42 
43 /* sequencer client, per UMP EP (rawmidi) */
44 struct seq_ump_client {
45 	struct snd_ump_endpoint *ump;	/* assigned endpoint */
46 	int seq_client;			/* sequencer client id */
47 	int opened[2];			/* current opens for each direction */
48 	struct snd_rawmidi_file out_rfile; /* rawmidi for output */
49 	struct seq_ump_input_buffer input; /* input parser context */
50 	struct seq_ump_group groups[SNDRV_UMP_MAX_GROUPS]; /* table of groups */
51 	void *ump_info[SNDRV_UMP_MAX_BLOCKS + 1]; /* shadow of seq client ump_info */
52 	struct work_struct group_notify_work; /* FB change notification */
53 };
54 
55 /* number of 32bit words for each UMP message type */
56 static unsigned char ump_packet_words[0x10] = {
57 	1, 1, 1, 2, 2, 4, 1, 1, 2, 2, 2, 3, 3, 4, 4, 4
58 };
59 
60 /* conversion between UMP group and seq port;
61  * assume the port number is equal with UMP group number (1-based)
62  */
63 static unsigned char ump_group_to_seq_port(unsigned char group)
64 {
65 	return group + 1;
66 }
67 
68 /* process the incoming rawmidi stream */
69 static void seq_ump_input_receive(struct snd_ump_endpoint *ump,
70 				  const u32 *val, int words)
71 {
72 	struct seq_ump_client *client = ump->seq_client;
73 	struct snd_seq_ump_event ev = {};
74 
75 	if (!client->opened[STR_IN])
76 		return;
77 
78 	if (ump_is_groupless_msg(ump_message_type(*val)))
79 		ev.source.port = 0; /* UMP EP port */
80 	else
81 		ev.source.port = ump_group_to_seq_port(ump_message_group(*val));
82 	ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
83 	ev.flags = SNDRV_SEQ_EVENT_UMP;
84 	memcpy(ev.ump, val, words << 2);
85 	snd_seq_kernel_client_dispatch(client->seq_client,
86 				       (struct snd_seq_event *)&ev,
87 				       true, 0);
88 }
89 
90 /* process an input sequencer event; only deal with UMP types */
91 static int seq_ump_process_event(struct snd_seq_event *ev, int direct,
92 				 void *private_data, int atomic, int hop)
93 {
94 	struct seq_ump_client *client = private_data;
95 	struct snd_rawmidi_substream *substream;
96 	struct snd_seq_ump_event *ump_ev;
97 	unsigned char type;
98 	int len;
99 
100 	substream = client->out_rfile.output;
101 	if (!substream)
102 		return -ENODEV;
103 	if (!snd_seq_ev_is_ump(ev))
104 		return 0; /* invalid event, skip */
105 	ump_ev = (struct snd_seq_ump_event *)ev;
106 	type = ump_message_type(ump_ev->ump[0]);
107 	len = ump_packet_words[type];
108 	if (len > 4)
109 		return 0; // invalid - skip
110 	snd_rawmidi_kernel_write(substream, ev->data.raw8.d, len << 2);
111 	return 0;
112 }
113 
114 /* open the rawmidi */
115 static int seq_ump_client_open(struct seq_ump_client *client, int dir)
116 {
117 	struct snd_ump_endpoint *ump = client->ump;
118 	int err = 0;
119 
120 	mutex_lock(&ump->open_mutex);
121 	if (dir == STR_OUT && !client->opened[dir]) {
122 		err = snd_rawmidi_kernel_open(&ump->core, 0,
123 					      SNDRV_RAWMIDI_LFLG_OUTPUT |
124 					      SNDRV_RAWMIDI_LFLG_APPEND,
125 					      &client->out_rfile);
126 		if (err < 0)
127 			goto unlock;
128 	}
129 	client->opened[dir]++;
130  unlock:
131 	mutex_unlock(&ump->open_mutex);
132 	return err;
133 }
134 
135 /* close the rawmidi */
136 static int seq_ump_client_close(struct seq_ump_client *client, int dir)
137 {
138 	struct snd_ump_endpoint *ump = client->ump;
139 
140 	mutex_lock(&ump->open_mutex);
141 	if (!--client->opened[dir])
142 		if (dir == STR_OUT)
143 			snd_rawmidi_kernel_release(&client->out_rfile);
144 	mutex_unlock(&ump->open_mutex);
145 	return 0;
146 }
147 
148 /* sequencer subscription ops for each client */
149 static int seq_ump_subscribe(void *pdata, struct snd_seq_port_subscribe *info)
150 {
151 	struct seq_ump_client *client = pdata;
152 
153 	return seq_ump_client_open(client, STR_IN);
154 }
155 
156 static int seq_ump_unsubscribe(void *pdata, struct snd_seq_port_subscribe *info)
157 {
158 	struct seq_ump_client *client = pdata;
159 
160 	return seq_ump_client_close(client, STR_IN);
161 }
162 
163 static int seq_ump_use(void *pdata, struct snd_seq_port_subscribe *info)
164 {
165 	struct seq_ump_client *client = pdata;
166 
167 	return seq_ump_client_open(client, STR_OUT);
168 }
169 
170 static int seq_ump_unuse(void *pdata, struct snd_seq_port_subscribe *info)
171 {
172 	struct seq_ump_client *client = pdata;
173 
174 	return seq_ump_client_close(client, STR_OUT);
175 }
176 
177 /* fill port_info from the given UMP EP and group info */
178 static void fill_port_info(struct snd_seq_port_info *port,
179 			   struct seq_ump_client *client,
180 			   struct seq_ump_group *group)
181 {
182 	unsigned int rawmidi_info = client->ump->core.info_flags;
183 
184 	port->addr.client = client->seq_client;
185 	port->addr.port = ump_group_to_seq_port(group->group);
186 	port->capability = 0;
187 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_OUTPUT)
188 		port->capability |= SNDRV_SEQ_PORT_CAP_WRITE |
189 			SNDRV_SEQ_PORT_CAP_SYNC_WRITE |
190 			SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
191 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_INPUT)
192 		port->capability |= SNDRV_SEQ_PORT_CAP_READ |
193 			SNDRV_SEQ_PORT_CAP_SYNC_READ |
194 			SNDRV_SEQ_PORT_CAP_SUBS_READ;
195 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_DUPLEX)
196 		port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
197 	if (group->dir_bits & (1 << STR_IN))
198 		port->direction |= SNDRV_SEQ_PORT_DIR_INPUT;
199 	if (group->dir_bits & (1 << STR_OUT))
200 		port->direction |= SNDRV_SEQ_PORT_DIR_OUTPUT;
201 	port->ump_group = group->group + 1;
202 	if (!group->active)
203 		port->capability |= SNDRV_SEQ_PORT_CAP_INACTIVE;
204 	port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC |
205 		SNDRV_SEQ_PORT_TYPE_MIDI_UMP |
206 		SNDRV_SEQ_PORT_TYPE_HARDWARE |
207 		SNDRV_SEQ_PORT_TYPE_PORT;
208 	port->midi_channels = 16;
209 	if (*group->name)
210 		snprintf(port->name, sizeof(port->name), "Group %d (%s)",
211 			 group->group + 1, group->name);
212 	else
213 		sprintf(port->name, "Group %d", group->group + 1);
214 }
215 
216 /* create a new sequencer port per UMP group */
217 static int seq_ump_group_init(struct seq_ump_client *client, int group_index)
218 {
219 	struct seq_ump_group *group = &client->groups[group_index];
220 	struct snd_seq_port_info *port;
221 	struct snd_seq_port_callback pcallbacks;
222 	int err;
223 
224 	port = kzalloc(sizeof(*port), GFP_KERNEL);
225 	if (!port) {
226 		err = -ENOMEM;
227 		goto error;
228 	}
229 
230 	fill_port_info(port, client, group);
231 	port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
232 	memset(&pcallbacks, 0, sizeof(pcallbacks));
233 	pcallbacks.owner = THIS_MODULE;
234 	pcallbacks.private_data = client;
235 	pcallbacks.subscribe = seq_ump_subscribe;
236 	pcallbacks.unsubscribe = seq_ump_unsubscribe;
237 	pcallbacks.use = seq_ump_use;
238 	pcallbacks.unuse = seq_ump_unuse;
239 	pcallbacks.event_input = seq_ump_process_event;
240 	port->kernel = &pcallbacks;
241 	err = snd_seq_kernel_client_ctl(client->seq_client,
242 					SNDRV_SEQ_IOCTL_CREATE_PORT,
243 					port);
244  error:
245 	kfree(port);
246 	return err;
247 }
248 
249 /* update the sequencer ports; called from notify_fb_change callback */
250 static void update_port_infos(struct seq_ump_client *client)
251 {
252 	struct snd_seq_port_info *old, *new;
253 	int i, err;
254 
255 	old = kzalloc(sizeof(*old), GFP_KERNEL);
256 	new = kzalloc(sizeof(*new), GFP_KERNEL);
257 	if (!old || !new)
258 		goto error;
259 
260 	for (i = 0; i < SNDRV_UMP_MAX_GROUPS; i++) {
261 		old->addr.client = client->seq_client;
262 		old->addr.port = i;
263 		err = snd_seq_kernel_client_ctl(client->seq_client,
264 						SNDRV_SEQ_IOCTL_GET_PORT_INFO,
265 						old);
266 		if (err < 0)
267 			goto error;
268 		fill_port_info(new, client, &client->groups[i]);
269 		if (old->capability == new->capability &&
270 		    !strcmp(old->name, new->name))
271 			continue;
272 		err = snd_seq_kernel_client_ctl(client->seq_client,
273 						SNDRV_SEQ_IOCTL_SET_PORT_INFO,
274 						new);
275 		if (err < 0)
276 			goto error;
277 		/* notify to system port */
278 		snd_seq_system_client_ev_port_change(client->seq_client, i);
279 	}
280  error:
281 	kfree(new);
282 	kfree(old);
283 }
284 
285 /* update dir_bits and active flag for all groups in the client */
286 static void update_group_attrs(struct seq_ump_client *client)
287 {
288 	struct snd_ump_block *fb;
289 	struct seq_ump_group *group;
290 	int i;
291 
292 	for (i = 0; i < SNDRV_UMP_MAX_GROUPS; i++) {
293 		group = &client->groups[i];
294 		*group->name = 0;
295 		group->dir_bits = 0;
296 		group->active = 0;
297 		group->group = i;
298 	}
299 
300 	list_for_each_entry(fb, &client->ump->block_list, list) {
301 		if (fb->info.first_group + fb->info.num_groups > SNDRV_UMP_MAX_GROUPS)
302 			break;
303 		group = &client->groups[fb->info.first_group];
304 		for (i = 0; i < fb->info.num_groups; i++, group++) {
305 			if (fb->info.active)
306 				group->active = 1;
307 			switch (fb->info.direction) {
308 			case SNDRV_UMP_DIR_INPUT:
309 				group->dir_bits |= (1 << STR_IN);
310 				break;
311 			case SNDRV_UMP_DIR_OUTPUT:
312 				group->dir_bits |= (1 << STR_OUT);
313 				break;
314 			case SNDRV_UMP_DIR_BIDIRECTION:
315 				group->dir_bits |= (1 << STR_OUT) | (1 << STR_IN);
316 				break;
317 			}
318 			if (!*fb->info.name)
319 				continue;
320 			if (!*group->name) {
321 				/* store the first matching name */
322 				strscpy(group->name, fb->info.name,
323 					sizeof(group->name));
324 			} else {
325 				/* when overlapping, concat names */
326 				strlcat(group->name, ", ", sizeof(group->name));
327 				strlcat(group->name, fb->info.name,
328 					sizeof(group->name));
329 			}
330 		}
331 	}
332 }
333 
334 /* create a UMP Endpoint port */
335 static int create_ump_endpoint_port(struct seq_ump_client *client)
336 {
337 	struct snd_seq_port_info *port;
338 	struct snd_seq_port_callback pcallbacks;
339 	unsigned int rawmidi_info = client->ump->core.info_flags;
340 	int err;
341 
342 	port = kzalloc(sizeof(*port), GFP_KERNEL);
343 	if (!port)
344 		return -ENOMEM;
345 
346 	port->addr.client = client->seq_client;
347 	port->addr.port = 0; /* fixed */
348 	port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
349 	port->capability = SNDRV_SEQ_PORT_CAP_UMP_ENDPOINT;
350 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_INPUT) {
351 		port->capability |= SNDRV_SEQ_PORT_CAP_READ |
352 			SNDRV_SEQ_PORT_CAP_SYNC_READ |
353 			SNDRV_SEQ_PORT_CAP_SUBS_READ;
354 		port->direction |= SNDRV_SEQ_PORT_DIR_INPUT;
355 	}
356 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_OUTPUT) {
357 		port->capability |= SNDRV_SEQ_PORT_CAP_WRITE |
358 			SNDRV_SEQ_PORT_CAP_SYNC_WRITE |
359 			SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
360 		port->direction |= SNDRV_SEQ_PORT_DIR_OUTPUT;
361 	}
362 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_DUPLEX)
363 		port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
364 	port->ump_group = 0; /* no associated group, no conversion */
365 	port->type = SNDRV_SEQ_PORT_TYPE_MIDI_UMP |
366 		SNDRV_SEQ_PORT_TYPE_HARDWARE |
367 		SNDRV_SEQ_PORT_TYPE_PORT;
368 	port->midi_channels = 16;
369 	strcpy(port->name, "MIDI 2.0");
370 	memset(&pcallbacks, 0, sizeof(pcallbacks));
371 	pcallbacks.owner = THIS_MODULE;
372 	pcallbacks.private_data = client;
373 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_INPUT) {
374 		pcallbacks.subscribe = seq_ump_subscribe;
375 		pcallbacks.unsubscribe = seq_ump_unsubscribe;
376 	}
377 	if (rawmidi_info & SNDRV_RAWMIDI_INFO_OUTPUT) {
378 		pcallbacks.use = seq_ump_use;
379 		pcallbacks.unuse = seq_ump_unuse;
380 		pcallbacks.event_input = seq_ump_process_event;
381 	}
382 	port->kernel = &pcallbacks;
383 	err = snd_seq_kernel_client_ctl(client->seq_client,
384 					SNDRV_SEQ_IOCTL_CREATE_PORT,
385 					port);
386 	kfree(port);
387 	return err;
388 }
389 
390 /* release the client resources */
391 static void seq_ump_client_free(struct seq_ump_client *client)
392 {
393 	cancel_work_sync(&client->group_notify_work);
394 
395 	if (client->seq_client >= 0)
396 		snd_seq_delete_kernel_client(client->seq_client);
397 
398 	client->ump->seq_ops = NULL;
399 	client->ump->seq_client = NULL;
400 
401 	kfree(client);
402 }
403 
404 /* update the MIDI version for the given client */
405 static void setup_client_midi_version(struct seq_ump_client *client)
406 {
407 	struct snd_seq_client *cptr;
408 
409 	cptr = snd_seq_kernel_client_get(client->seq_client);
410 	if (!cptr)
411 		return;
412 	if (client->ump->info.protocol & SNDRV_UMP_EP_INFO_PROTO_MIDI2)
413 		cptr->midi_version = SNDRV_SEQ_CLIENT_UMP_MIDI_2_0;
414 	else
415 		cptr->midi_version = SNDRV_SEQ_CLIENT_UMP_MIDI_1_0;
416 	snd_seq_kernel_client_put(cptr);
417 }
418 
419 /* UMP group change notification */
420 static void handle_group_notify(struct work_struct *work)
421 {
422 	struct seq_ump_client *client =
423 		container_of(work, struct seq_ump_client, group_notify_work);
424 
425 	update_group_attrs(client);
426 	update_port_infos(client);
427 }
428 
429 /* UMP FB change notification */
430 static int seq_ump_notify_fb_change(struct snd_ump_endpoint *ump,
431 				    struct snd_ump_block *fb)
432 {
433 	struct seq_ump_client *client = ump->seq_client;
434 
435 	if (!client)
436 		return -ENODEV;
437 	schedule_work(&client->group_notify_work);
438 	return 0;
439 }
440 
441 /* UMP protocol change notification; just update the midi_version field */
442 static int seq_ump_switch_protocol(struct snd_ump_endpoint *ump)
443 {
444 	if (!ump->seq_client)
445 		return -ENODEV;
446 	setup_client_midi_version(ump->seq_client);
447 	return 0;
448 }
449 
450 static const struct snd_seq_ump_ops seq_ump_ops = {
451 	.input_receive = seq_ump_input_receive,
452 	.notify_fb_change = seq_ump_notify_fb_change,
453 	.switch_protocol = seq_ump_switch_protocol,
454 };
455 
456 /* create a sequencer client and ports for the given UMP endpoint */
457 static int snd_seq_ump_probe(struct device *_dev)
458 {
459 	struct snd_seq_device *dev = to_seq_dev(_dev);
460 	struct snd_ump_endpoint *ump = dev->private_data;
461 	struct snd_card *card = dev->card;
462 	struct seq_ump_client *client;
463 	struct snd_ump_block *fb;
464 	struct snd_seq_client *cptr;
465 	int p, err;
466 
467 	client = kzalloc(sizeof(*client), GFP_KERNEL);
468 	if (!client)
469 		return -ENOMEM;
470 
471 	INIT_WORK(&client->group_notify_work, handle_group_notify);
472 	client->ump = ump;
473 
474 	client->seq_client =
475 		snd_seq_create_kernel_client(card, ump->core.device,
476 					     ump->core.name);
477 	if (client->seq_client < 0) {
478 		err = client->seq_client;
479 		goto error;
480 	}
481 
482 	client->ump_info[0] = &ump->info;
483 	list_for_each_entry(fb, &ump->block_list, list)
484 		client->ump_info[fb->info.block_id + 1] = &fb->info;
485 
486 	setup_client_midi_version(client);
487 	update_group_attrs(client);
488 
489 	for (p = 0; p < SNDRV_UMP_MAX_GROUPS; p++) {
490 		err = seq_ump_group_init(client, p);
491 		if (err < 0)
492 			goto error;
493 	}
494 
495 	err = create_ump_endpoint_port(client);
496 	if (err < 0)
497 		goto error;
498 
499 	cptr = snd_seq_kernel_client_get(client->seq_client);
500 	if (!cptr) {
501 		err = -EINVAL;
502 		goto error;
503 	}
504 	cptr->ump_info = client->ump_info;
505 	snd_seq_kernel_client_put(cptr);
506 
507 	ump->seq_client = client;
508 	ump->seq_ops = &seq_ump_ops;
509 	return 0;
510 
511  error:
512 	seq_ump_client_free(client);
513 	return err;
514 }
515 
516 /* remove a sequencer client */
517 static int snd_seq_ump_remove(struct device *_dev)
518 {
519 	struct snd_seq_device *dev = to_seq_dev(_dev);
520 	struct snd_ump_endpoint *ump = dev->private_data;
521 
522 	if (ump->seq_client)
523 		seq_ump_client_free(ump->seq_client);
524 	return 0;
525 }
526 
527 static struct snd_seq_driver seq_ump_driver = {
528 	.driver = {
529 		.name = KBUILD_MODNAME,
530 		.probe = snd_seq_ump_probe,
531 		.remove = snd_seq_ump_remove,
532 	},
533 	.id = SNDRV_SEQ_DEV_ID_UMP,
534 	.argsize = 0,
535 };
536 
537 module_snd_seq_driver(seq_ump_driver);
538 
539 MODULE_DESCRIPTION("ALSA sequencer client for UMP rawmidi");
540 MODULE_LICENSE("GPL");
541