xref: /openbmc/linux/sound/firewire/isight.c (revision 9b446941)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Apple iSight audio driver
4  *
5  * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
6  */
7 
8 #include <asm/byteorder.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/firewire.h>
12 #include <linux/firewire-constants.h>
13 #include <linux/module.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/mutex.h>
16 #include <linux/string.h>
17 #include <sound/control.h>
18 #include <sound/core.h>
19 #include <sound/initval.h>
20 #include <sound/pcm.h>
21 #include <sound/tlv.h>
22 #include "lib.h"
23 #include "iso-resources.h"
24 #include "packets-buffer.h"
25 
26 #define OUI_APPLE		0x000a27
27 #define MODEL_APPLE_ISIGHT	0x000008
28 #define SW_ISIGHT_AUDIO		0x000010
29 
30 #define REG_AUDIO_ENABLE	0x000
31 #define  AUDIO_ENABLE		0x80000000
32 #define REG_DEF_AUDIO_GAIN	0x204
33 #define REG_GAIN_RAW_START	0x210
34 #define REG_GAIN_RAW_END	0x214
35 #define REG_GAIN_DB_START	0x218
36 #define REG_GAIN_DB_END		0x21c
37 #define REG_SAMPLE_RATE_INQUIRY	0x280
38 #define REG_ISO_TX_CONFIG	0x300
39 #define  SPEED_SHIFT		16
40 #define REG_SAMPLE_RATE		0x400
41 #define  RATE_48000		0x80000000
42 #define REG_GAIN		0x500
43 #define REG_MUTE		0x504
44 
45 #define MAX_FRAMES_PER_PACKET	475
46 
47 #define QUEUE_LENGTH		20
48 
49 struct isight {
50 	struct snd_card *card;
51 	struct fw_unit *unit;
52 	struct fw_device *device;
53 	u64 audio_base;
54 	struct snd_pcm_substream *pcm;
55 	struct mutex mutex;
56 	struct iso_packets_buffer buffer;
57 	struct fw_iso_resources resources;
58 	struct fw_iso_context *context;
59 	bool pcm_active;
60 	bool pcm_running;
61 	bool first_packet;
62 	int packet_index;
63 	u32 total_samples;
64 	unsigned int buffer_pointer;
65 	unsigned int period_counter;
66 	s32 gain_min, gain_max;
67 	unsigned int gain_tlv[4];
68 };
69 
70 struct audio_payload {
71 	__be32 sample_count;
72 	__be32 signature;
73 	__be32 sample_total;
74 	__be32 reserved;
75 	__be16 samples[2 * MAX_FRAMES_PER_PACKET];
76 };
77 
78 MODULE_DESCRIPTION("iSight audio driver");
79 MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
80 MODULE_LICENSE("GPL");
81 
82 static struct fw_iso_packet audio_packet = {
83 	.payload_length = sizeof(struct audio_payload),
84 	.interrupt = 1,
85 	.header_length = 4,
86 };
87 
isight_update_pointers(struct isight * isight,unsigned int count)88 static void isight_update_pointers(struct isight *isight, unsigned int count)
89 {
90 	struct snd_pcm_runtime *runtime = isight->pcm->runtime;
91 	unsigned int ptr;
92 
93 	smp_wmb(); /* update buffer data before buffer pointer */
94 
95 	ptr = isight->buffer_pointer;
96 	ptr += count;
97 	if (ptr >= runtime->buffer_size)
98 		ptr -= runtime->buffer_size;
99 	WRITE_ONCE(isight->buffer_pointer, ptr);
100 
101 	isight->period_counter += count;
102 	if (isight->period_counter >= runtime->period_size) {
103 		isight->period_counter -= runtime->period_size;
104 		snd_pcm_period_elapsed(isight->pcm);
105 	}
106 }
107 
isight_samples(struct isight * isight,const __be16 * samples,unsigned int count)108 static void isight_samples(struct isight *isight,
109 			   const __be16 *samples, unsigned int count)
110 {
111 	struct snd_pcm_runtime *runtime;
112 	unsigned int count1;
113 
114 	if (!READ_ONCE(isight->pcm_running))
115 		return;
116 
117 	runtime = isight->pcm->runtime;
118 	if (isight->buffer_pointer + count <= runtime->buffer_size) {
119 		memcpy(runtime->dma_area + isight->buffer_pointer * 4,
120 		       samples, count * 4);
121 	} else {
122 		count1 = runtime->buffer_size - isight->buffer_pointer;
123 		memcpy(runtime->dma_area + isight->buffer_pointer * 4,
124 		       samples, count1 * 4);
125 		samples += count1 * 2;
126 		memcpy(runtime->dma_area, samples, (count - count1) * 4);
127 	}
128 
129 	isight_update_pointers(isight, count);
130 }
131 
isight_pcm_abort(struct isight * isight)132 static void isight_pcm_abort(struct isight *isight)
133 {
134 	if (READ_ONCE(isight->pcm_active))
135 		snd_pcm_stop_xrun(isight->pcm);
136 }
137 
isight_dropped_samples(struct isight * isight,unsigned int total)138 static void isight_dropped_samples(struct isight *isight, unsigned int total)
139 {
140 	struct snd_pcm_runtime *runtime;
141 	u32 dropped;
142 	unsigned int count1;
143 
144 	if (!READ_ONCE(isight->pcm_running))
145 		return;
146 
147 	runtime = isight->pcm->runtime;
148 	dropped = total - isight->total_samples;
149 	if (dropped < runtime->buffer_size) {
150 		if (isight->buffer_pointer + dropped <= runtime->buffer_size) {
151 			memset(runtime->dma_area + isight->buffer_pointer * 4,
152 			       0, dropped * 4);
153 		} else {
154 			count1 = runtime->buffer_size - isight->buffer_pointer;
155 			memset(runtime->dma_area + isight->buffer_pointer * 4,
156 			       0, count1 * 4);
157 			memset(runtime->dma_area, 0, (dropped - count1) * 4);
158 		}
159 		isight_update_pointers(isight, dropped);
160 	} else {
161 		isight_pcm_abort(isight);
162 	}
163 }
164 
isight_packet(struct fw_iso_context * context,u32 cycle,size_t header_length,void * header,void * data)165 static void isight_packet(struct fw_iso_context *context, u32 cycle,
166 			  size_t header_length, void *header, void *data)
167 {
168 	struct isight *isight = data;
169 	const struct audio_payload *payload;
170 	unsigned int index, length, count, total;
171 	int err;
172 
173 	if (isight->packet_index < 0)
174 		return;
175 	index = isight->packet_index;
176 	payload = isight->buffer.packets[index].buffer;
177 	length = be32_to_cpup(header) >> 16;
178 
179 	if (likely(length >= 16 &&
180 		   payload->signature == cpu_to_be32(0x73676874/*"sght"*/))) {
181 		count = be32_to_cpu(payload->sample_count);
182 		if (likely(count <= (length - 16) / 4)) {
183 			total = be32_to_cpu(payload->sample_total);
184 			if (unlikely(total != isight->total_samples)) {
185 				if (!isight->first_packet)
186 					isight_dropped_samples(isight, total);
187 				isight->first_packet = false;
188 				isight->total_samples = total;
189 			}
190 
191 			isight_samples(isight, payload->samples, count);
192 			isight->total_samples += count;
193 		}
194 	}
195 
196 	err = fw_iso_context_queue(isight->context, &audio_packet,
197 				   &isight->buffer.iso_buffer,
198 				   isight->buffer.packets[index].offset);
199 	if (err < 0) {
200 		dev_err(&isight->unit->device, "queueing error: %d\n", err);
201 		isight_pcm_abort(isight);
202 		isight->packet_index = -1;
203 		return;
204 	}
205 	fw_iso_context_queue_flush(isight->context);
206 
207 	if (++index >= QUEUE_LENGTH)
208 		index = 0;
209 	isight->packet_index = index;
210 }
211 
isight_connect(struct isight * isight)212 static int isight_connect(struct isight *isight)
213 {
214 	int ch, err;
215 	__be32 value;
216 
217 retry_after_bus_reset:
218 	ch = fw_iso_resources_allocate(&isight->resources,
219 				       sizeof(struct audio_payload),
220 				       isight->device->max_speed);
221 	if (ch < 0) {
222 		err = ch;
223 		goto error;
224 	}
225 
226 	value = cpu_to_be32(ch | (isight->device->max_speed << SPEED_SHIFT));
227 	err = snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
228 				 isight->audio_base + REG_ISO_TX_CONFIG,
229 				 &value, 4, FW_FIXED_GENERATION |
230 				 isight->resources.generation);
231 	if (err == -EAGAIN) {
232 		fw_iso_resources_free(&isight->resources);
233 		goto retry_after_bus_reset;
234 	} else if (err < 0) {
235 		goto err_resources;
236 	}
237 
238 	return 0;
239 
240 err_resources:
241 	fw_iso_resources_free(&isight->resources);
242 error:
243 	return err;
244 }
245 
isight_open(struct snd_pcm_substream * substream)246 static int isight_open(struct snd_pcm_substream *substream)
247 {
248 	static const struct snd_pcm_hardware hardware = {
249 		.info = SNDRV_PCM_INFO_MMAP |
250 			SNDRV_PCM_INFO_MMAP_VALID |
251 			SNDRV_PCM_INFO_BATCH |
252 			SNDRV_PCM_INFO_INTERLEAVED |
253 			SNDRV_PCM_INFO_BLOCK_TRANSFER,
254 		.formats = SNDRV_PCM_FMTBIT_S16_BE,
255 		.rates = SNDRV_PCM_RATE_48000,
256 		.rate_min = 48000,
257 		.rate_max = 48000,
258 		.channels_min = 2,
259 		.channels_max = 2,
260 		.buffer_bytes_max = 4 * 1024 * 1024,
261 		.period_bytes_min = MAX_FRAMES_PER_PACKET * 4,
262 		.period_bytes_max = 1024 * 1024,
263 		.periods_min = 2,
264 		.periods_max = UINT_MAX,
265 	};
266 	struct isight *isight = substream->private_data;
267 
268 	substream->runtime->hw = hardware;
269 
270 	return iso_packets_buffer_init(&isight->buffer, isight->unit,
271 				       QUEUE_LENGTH,
272 				       sizeof(struct audio_payload),
273 				       DMA_FROM_DEVICE);
274 }
275 
isight_close(struct snd_pcm_substream * substream)276 static int isight_close(struct snd_pcm_substream *substream)
277 {
278 	struct isight *isight = substream->private_data;
279 
280 	iso_packets_buffer_destroy(&isight->buffer, isight->unit);
281 
282 	return 0;
283 }
284 
isight_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * hw_params)285 static int isight_hw_params(struct snd_pcm_substream *substream,
286 			    struct snd_pcm_hw_params *hw_params)
287 {
288 	struct isight *isight = substream->private_data;
289 
290 	WRITE_ONCE(isight->pcm_active, true);
291 
292 	return 0;
293 }
294 
reg_read(struct isight * isight,int offset,__be32 * value)295 static int reg_read(struct isight *isight, int offset, __be32 *value)
296 {
297 	return snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
298 				  isight->audio_base + offset, value, 4, 0);
299 }
300 
reg_write(struct isight * isight,int offset,__be32 value)301 static int reg_write(struct isight *isight, int offset, __be32 value)
302 {
303 	return snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
304 				  isight->audio_base + offset, &value, 4, 0);
305 }
306 
isight_stop_streaming(struct isight * isight)307 static void isight_stop_streaming(struct isight *isight)
308 {
309 	__be32 value;
310 
311 	if (!isight->context)
312 		return;
313 
314 	fw_iso_context_stop(isight->context);
315 	fw_iso_context_destroy(isight->context);
316 	isight->context = NULL;
317 	fw_iso_resources_free(&isight->resources);
318 	value = 0;
319 	snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
320 			   isight->audio_base + REG_AUDIO_ENABLE,
321 			   &value, 4, FW_QUIET);
322 }
323 
isight_hw_free(struct snd_pcm_substream * substream)324 static int isight_hw_free(struct snd_pcm_substream *substream)
325 {
326 	struct isight *isight = substream->private_data;
327 
328 	WRITE_ONCE(isight->pcm_active, false);
329 
330 	mutex_lock(&isight->mutex);
331 	isight_stop_streaming(isight);
332 	mutex_unlock(&isight->mutex);
333 
334 	return 0;
335 }
336 
isight_start_streaming(struct isight * isight)337 static int isight_start_streaming(struct isight *isight)
338 {
339 	unsigned int i;
340 	int err;
341 
342 	if (isight->context) {
343 		if (isight->packet_index < 0)
344 			isight_stop_streaming(isight);
345 		else
346 			return 0;
347 	}
348 
349 	err = reg_write(isight, REG_SAMPLE_RATE, cpu_to_be32(RATE_48000));
350 	if (err < 0)
351 		goto error;
352 
353 	err = isight_connect(isight);
354 	if (err < 0)
355 		goto error;
356 
357 	err = reg_write(isight, REG_AUDIO_ENABLE, cpu_to_be32(AUDIO_ENABLE));
358 	if (err < 0)
359 		goto err_resources;
360 
361 	isight->context = fw_iso_context_create(isight->device->card,
362 						FW_ISO_CONTEXT_RECEIVE,
363 						isight->resources.channel,
364 						isight->device->max_speed,
365 						4, isight_packet, isight);
366 	if (IS_ERR(isight->context)) {
367 		err = PTR_ERR(isight->context);
368 		isight->context = NULL;
369 		goto err_resources;
370 	}
371 
372 	for (i = 0; i < QUEUE_LENGTH; ++i) {
373 		err = fw_iso_context_queue(isight->context, &audio_packet,
374 					   &isight->buffer.iso_buffer,
375 					   isight->buffer.packets[i].offset);
376 		if (err < 0)
377 			goto err_context;
378 	}
379 
380 	isight->first_packet = true;
381 	isight->packet_index = 0;
382 
383 	err = fw_iso_context_start(isight->context, -1, 0,
384 				   FW_ISO_CONTEXT_MATCH_ALL_TAGS/*?*/);
385 	if (err < 0)
386 		goto err_context;
387 
388 	return 0;
389 
390 err_context:
391 	fw_iso_context_destroy(isight->context);
392 	isight->context = NULL;
393 err_resources:
394 	fw_iso_resources_free(&isight->resources);
395 	reg_write(isight, REG_AUDIO_ENABLE, 0);
396 error:
397 	return err;
398 }
399 
isight_prepare(struct snd_pcm_substream * substream)400 static int isight_prepare(struct snd_pcm_substream *substream)
401 {
402 	struct isight *isight = substream->private_data;
403 	int err;
404 
405 	isight->buffer_pointer = 0;
406 	isight->period_counter = 0;
407 
408 	mutex_lock(&isight->mutex);
409 	err = isight_start_streaming(isight);
410 	mutex_unlock(&isight->mutex);
411 
412 	return err;
413 }
414 
isight_trigger(struct snd_pcm_substream * substream,int cmd)415 static int isight_trigger(struct snd_pcm_substream *substream, int cmd)
416 {
417 	struct isight *isight = substream->private_data;
418 
419 	switch (cmd) {
420 	case SNDRV_PCM_TRIGGER_START:
421 		WRITE_ONCE(isight->pcm_running, true);
422 		break;
423 	case SNDRV_PCM_TRIGGER_STOP:
424 		WRITE_ONCE(isight->pcm_running, false);
425 		break;
426 	default:
427 		return -EINVAL;
428 	}
429 	return 0;
430 }
431 
isight_pointer(struct snd_pcm_substream * substream)432 static snd_pcm_uframes_t isight_pointer(struct snd_pcm_substream *substream)
433 {
434 	struct isight *isight = substream->private_data;
435 
436 	return READ_ONCE(isight->buffer_pointer);
437 }
438 
isight_create_pcm(struct isight * isight)439 static int isight_create_pcm(struct isight *isight)
440 {
441 	static const struct snd_pcm_ops ops = {
442 		.open      = isight_open,
443 		.close     = isight_close,
444 		.hw_params = isight_hw_params,
445 		.hw_free   = isight_hw_free,
446 		.prepare   = isight_prepare,
447 		.trigger   = isight_trigger,
448 		.pointer   = isight_pointer,
449 	};
450 	struct snd_pcm *pcm;
451 	int err;
452 
453 	err = snd_pcm_new(isight->card, "iSight", 0, 0, 1, &pcm);
454 	if (err < 0)
455 		return err;
456 	pcm->private_data = isight;
457 	strcpy(pcm->name, "iSight");
458 	isight->pcm = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
459 	isight->pcm->ops = &ops;
460 	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
461 
462 	return 0;
463 }
464 
isight_gain_info(struct snd_kcontrol * ctl,struct snd_ctl_elem_info * info)465 static int isight_gain_info(struct snd_kcontrol *ctl,
466 			    struct snd_ctl_elem_info *info)
467 {
468 	struct isight *isight = ctl->private_data;
469 
470 	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
471 	info->count = 1;
472 	info->value.integer.min = isight->gain_min;
473 	info->value.integer.max = isight->gain_max;
474 
475 	return 0;
476 }
477 
isight_gain_get(struct snd_kcontrol * ctl,struct snd_ctl_elem_value * value)478 static int isight_gain_get(struct snd_kcontrol *ctl,
479 			   struct snd_ctl_elem_value *value)
480 {
481 	struct isight *isight = ctl->private_data;
482 	__be32 gain;
483 	int err;
484 
485 	err = reg_read(isight, REG_GAIN, &gain);
486 	if (err < 0)
487 		return err;
488 
489 	value->value.integer.value[0] = (s32)be32_to_cpu(gain);
490 
491 	return 0;
492 }
493 
isight_gain_put(struct snd_kcontrol * ctl,struct snd_ctl_elem_value * value)494 static int isight_gain_put(struct snd_kcontrol *ctl,
495 			   struct snd_ctl_elem_value *value)
496 {
497 	struct isight *isight = ctl->private_data;
498 
499 	if (value->value.integer.value[0] < isight->gain_min ||
500 	    value->value.integer.value[0] > isight->gain_max)
501 		return -EINVAL;
502 
503 	return reg_write(isight, REG_GAIN,
504 			 cpu_to_be32(value->value.integer.value[0]));
505 }
506 
isight_mute_get(struct snd_kcontrol * ctl,struct snd_ctl_elem_value * value)507 static int isight_mute_get(struct snd_kcontrol *ctl,
508 			   struct snd_ctl_elem_value *value)
509 {
510 	struct isight *isight = ctl->private_data;
511 	__be32 mute;
512 	int err;
513 
514 	err = reg_read(isight, REG_MUTE, &mute);
515 	if (err < 0)
516 		return err;
517 
518 	value->value.integer.value[0] = !mute;
519 
520 	return 0;
521 }
522 
isight_mute_put(struct snd_kcontrol * ctl,struct snd_ctl_elem_value * value)523 static int isight_mute_put(struct snd_kcontrol *ctl,
524 			   struct snd_ctl_elem_value *value)
525 {
526 	struct isight *isight = ctl->private_data;
527 
528 	return reg_write(isight, REG_MUTE,
529 			 (__force __be32)!value->value.integer.value[0]);
530 }
531 
isight_create_mixer(struct isight * isight)532 static int isight_create_mixer(struct isight *isight)
533 {
534 	static const struct snd_kcontrol_new gain_control = {
535 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
536 		.name = "Mic Capture Volume",
537 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
538 			  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
539 		.info = isight_gain_info,
540 		.get = isight_gain_get,
541 		.put = isight_gain_put,
542 	};
543 	static const struct snd_kcontrol_new mute_control = {
544 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
545 		.name = "Mic Capture Switch",
546 		.info = snd_ctl_boolean_mono_info,
547 		.get = isight_mute_get,
548 		.put = isight_mute_put,
549 	};
550 	__be32 value;
551 	struct snd_kcontrol *ctl;
552 	int err;
553 
554 	err = reg_read(isight, REG_GAIN_RAW_START, &value);
555 	if (err < 0)
556 		return err;
557 	isight->gain_min = be32_to_cpu(value);
558 
559 	err = reg_read(isight, REG_GAIN_RAW_END, &value);
560 	if (err < 0)
561 		return err;
562 	isight->gain_max = be32_to_cpu(value);
563 
564 	isight->gain_tlv[SNDRV_CTL_TLVO_TYPE] = SNDRV_CTL_TLVT_DB_MINMAX;
565 	isight->gain_tlv[SNDRV_CTL_TLVO_LEN] = 2 * sizeof(unsigned int);
566 
567 	err = reg_read(isight, REG_GAIN_DB_START, &value);
568 	if (err < 0)
569 		return err;
570 	isight->gain_tlv[SNDRV_CTL_TLVO_DB_MINMAX_MIN] =
571 						(s32)be32_to_cpu(value) * 100;
572 
573 	err = reg_read(isight, REG_GAIN_DB_END, &value);
574 	if (err < 0)
575 		return err;
576 	isight->gain_tlv[SNDRV_CTL_TLVO_DB_MINMAX_MAX] =
577 						(s32)be32_to_cpu(value) * 100;
578 
579 	ctl = snd_ctl_new1(&gain_control, isight);
580 	if (ctl)
581 		ctl->tlv.p = isight->gain_tlv;
582 	err = snd_ctl_add(isight->card, ctl);
583 	if (err < 0)
584 		return err;
585 
586 	err = snd_ctl_add(isight->card, snd_ctl_new1(&mute_control, isight));
587 	if (err < 0)
588 		return err;
589 
590 	return 0;
591 }
592 
isight_card_free(struct snd_card * card)593 static void isight_card_free(struct snd_card *card)
594 {
595 	struct isight *isight = card->private_data;
596 
597 	fw_iso_resources_destroy(&isight->resources);
598 }
599 
get_unit_base(struct fw_unit * unit)600 static u64 get_unit_base(struct fw_unit *unit)
601 {
602 	struct fw_csr_iterator i;
603 	int key, value;
604 
605 	fw_csr_iterator_init(&i, unit->directory);
606 	while (fw_csr_iterator_next(&i, &key, &value))
607 		if (key == CSR_OFFSET)
608 			return CSR_REGISTER_BASE + value * 4;
609 	return 0;
610 }
611 
isight_probe(struct fw_unit * unit,const struct ieee1394_device_id * id)612 static int isight_probe(struct fw_unit *unit,
613 			const struct ieee1394_device_id *id)
614 {
615 	struct fw_device *fw_dev = fw_parent_device(unit);
616 	struct snd_card *card;
617 	struct isight *isight;
618 	int err;
619 
620 	err = snd_card_new(&unit->device, -1, NULL, THIS_MODULE,
621 			   sizeof(*isight), &card);
622 	if (err < 0)
623 		return err;
624 
625 	isight = card->private_data;
626 	isight->card = card;
627 	mutex_init(&isight->mutex);
628 	isight->unit = fw_unit_get(unit);
629 	isight->device = fw_dev;
630 	isight->audio_base = get_unit_base(unit);
631 	if (!isight->audio_base) {
632 		dev_err(&unit->device, "audio unit base not found\n");
633 		err = -ENXIO;
634 		goto error;
635 	}
636 	fw_iso_resources_init(&isight->resources, unit);
637 
638 	card->private_free = isight_card_free;
639 
640 	strcpy(card->driver, "iSight");
641 	strcpy(card->shortname, "Apple iSight");
642 	snprintf(card->longname, sizeof(card->longname),
643 		 "Apple iSight (GUID %08x%08x) at %s, S%d",
644 		 fw_dev->config_rom[3], fw_dev->config_rom[4],
645 		 dev_name(&unit->device), 100 << fw_dev->max_speed);
646 	strcpy(card->mixername, "iSight");
647 
648 	err = isight_create_pcm(isight);
649 	if (err < 0)
650 		goto error;
651 
652 	err = isight_create_mixer(isight);
653 	if (err < 0)
654 		goto error;
655 
656 	err = snd_card_register(card);
657 	if (err < 0)
658 		goto error;
659 
660 	dev_set_drvdata(&unit->device, isight);
661 
662 	return 0;
663 error:
664 	snd_card_free(card);
665 
666 	mutex_destroy(&isight->mutex);
667 	fw_unit_put(isight->unit);
668 
669 	return err;
670 }
671 
isight_bus_reset(struct fw_unit * unit)672 static void isight_bus_reset(struct fw_unit *unit)
673 {
674 	struct isight *isight = dev_get_drvdata(&unit->device);
675 
676 	if (fw_iso_resources_update(&isight->resources) < 0) {
677 		isight_pcm_abort(isight);
678 
679 		mutex_lock(&isight->mutex);
680 		isight_stop_streaming(isight);
681 		mutex_unlock(&isight->mutex);
682 	}
683 }
684 
isight_remove(struct fw_unit * unit)685 static void isight_remove(struct fw_unit *unit)
686 {
687 	struct isight *isight = dev_get_drvdata(&unit->device);
688 
689 	isight_pcm_abort(isight);
690 
691 	snd_card_disconnect(isight->card);
692 
693 	mutex_lock(&isight->mutex);
694 	isight_stop_streaming(isight);
695 	mutex_unlock(&isight->mutex);
696 
697 	// Block till all of ALSA character devices are released.
698 	snd_card_free(isight->card);
699 
700 	mutex_destroy(&isight->mutex);
701 	fw_unit_put(isight->unit);
702 }
703 
704 static const struct ieee1394_device_id isight_id_table[] = {
705 	{
706 		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
707 				IEEE1394_MATCH_VERSION,
708 		.specifier_id = OUI_APPLE,
709 		.version      = SW_ISIGHT_AUDIO,
710 	},
711 	{ }
712 };
713 MODULE_DEVICE_TABLE(ieee1394, isight_id_table);
714 
715 static struct fw_driver isight_driver = {
716 	.driver   = {
717 		.owner	= THIS_MODULE,
718 		.name	= KBUILD_MODNAME,
719 		.bus	= &fw_bus_type,
720 	},
721 	.probe    = isight_probe,
722 	.update   = isight_bus_reset,
723 	.remove   = isight_remove,
724 	.id_table = isight_id_table,
725 };
726 
alsa_isight_init(void)727 static int __init alsa_isight_init(void)
728 {
729 	return driver_register(&isight_driver.driver);
730 }
731 
alsa_isight_exit(void)732 static void __exit alsa_isight_exit(void)
733 {
734 	driver_unregister(&isight_driver.driver);
735 }
736 
737 module_init(alsa_isight_init);
738 module_exit(alsa_isight_exit);
739