1/*
2 * Apple iSight audio 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 <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
49struct 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
70struct 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
78MODULE_DESCRIPTION("iSight audio driver");
79MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
80MODULE_LICENSE("GPL v2");
81
82static struct fw_iso_packet audio_packet = {
83	.payload_length = sizeof(struct audio_payload),
84	.interrupt = 1,
85	.header_length = 4,
86};
87
88static 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	ACCESS_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
108static 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 (!ACCESS_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
132static void isight_pcm_abort(struct isight *isight)
133{
134	if (ACCESS_ONCE(isight->pcm_active))
135		snd_pcm_stop_xrun(isight->pcm);
136}
137
138static 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 (!ACCESS_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
165static 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
212static int isight_connect(struct isight *isight)
213{
214	int ch, err;
215	__be32 value;
216
217retry_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
240err_resources:
241	fw_iso_resources_free(&isight->resources);
242error:
243	return err;
244}
245
246static 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
276static 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
285static 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	int err;
290
291	err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
292					       params_buffer_bytes(hw_params));
293	if (err < 0)
294		return err;
295
296	ACCESS_ONCE(isight->pcm_active) = true;
297
298	return 0;
299}
300
301static int reg_read(struct isight *isight, int offset, __be32 *value)
302{
303	return snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
304				  isight->audio_base + offset, value, 4, 0);
305}
306
307static int reg_write(struct isight *isight, int offset, __be32 value)
308{
309	return snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
310				  isight->audio_base + offset, &value, 4, 0);
311}
312
313static void isight_stop_streaming(struct isight *isight)
314{
315	__be32 value;
316
317	if (!isight->context)
318		return;
319
320	fw_iso_context_stop(isight->context);
321	fw_iso_context_destroy(isight->context);
322	isight->context = NULL;
323	fw_iso_resources_free(&isight->resources);
324	value = 0;
325	snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
326			   isight->audio_base + REG_AUDIO_ENABLE,
327			   &value, 4, FW_QUIET);
328}
329
330static int isight_hw_free(struct snd_pcm_substream *substream)
331{
332	struct isight *isight = substream->private_data;
333
334	ACCESS_ONCE(isight->pcm_active) = false;
335
336	mutex_lock(&isight->mutex);
337	isight_stop_streaming(isight);
338	mutex_unlock(&isight->mutex);
339
340	return snd_pcm_lib_free_vmalloc_buffer(substream);
341}
342
343static int isight_start_streaming(struct isight *isight)
344{
345	unsigned int i;
346	int err;
347
348	if (isight->context) {
349		if (isight->packet_index < 0)
350			isight_stop_streaming(isight);
351		else
352			return 0;
353	}
354
355	err = reg_write(isight, REG_SAMPLE_RATE, cpu_to_be32(RATE_48000));
356	if (err < 0)
357		goto error;
358
359	err = isight_connect(isight);
360	if (err < 0)
361		goto error;
362
363	err = reg_write(isight, REG_AUDIO_ENABLE, cpu_to_be32(AUDIO_ENABLE));
364	if (err < 0)
365		goto err_resources;
366
367	isight->context = fw_iso_context_create(isight->device->card,
368						FW_ISO_CONTEXT_RECEIVE,
369						isight->resources.channel,
370						isight->device->max_speed,
371						4, isight_packet, isight);
372	if (IS_ERR(isight->context)) {
373		err = PTR_ERR(isight->context);
374		isight->context = NULL;
375		goto err_resources;
376	}
377
378	for (i = 0; i < QUEUE_LENGTH; ++i) {
379		err = fw_iso_context_queue(isight->context, &audio_packet,
380					   &isight->buffer.iso_buffer,
381					   isight->buffer.packets[i].offset);
382		if (err < 0)
383			goto err_context;
384	}
385
386	isight->first_packet = true;
387	isight->packet_index = 0;
388
389	err = fw_iso_context_start(isight->context, -1, 0,
390				   FW_ISO_CONTEXT_MATCH_ALL_TAGS/*?*/);
391	if (err < 0)
392		goto err_context;
393
394	return 0;
395
396err_context:
397	fw_iso_context_destroy(isight->context);
398	isight->context = NULL;
399err_resources:
400	fw_iso_resources_free(&isight->resources);
401	reg_write(isight, REG_AUDIO_ENABLE, 0);
402error:
403	return err;
404}
405
406static int isight_prepare(struct snd_pcm_substream *substream)
407{
408	struct isight *isight = substream->private_data;
409	int err;
410
411	isight->buffer_pointer = 0;
412	isight->period_counter = 0;
413
414	mutex_lock(&isight->mutex);
415	err = isight_start_streaming(isight);
416	mutex_unlock(&isight->mutex);
417
418	return err;
419}
420
421static int isight_trigger(struct snd_pcm_substream *substream, int cmd)
422{
423	struct isight *isight = substream->private_data;
424
425	switch (cmd) {
426	case SNDRV_PCM_TRIGGER_START:
427		ACCESS_ONCE(isight->pcm_running) = true;
428		break;
429	case SNDRV_PCM_TRIGGER_STOP:
430		ACCESS_ONCE(isight->pcm_running) = false;
431		break;
432	default:
433		return -EINVAL;
434	}
435	return 0;
436}
437
438static snd_pcm_uframes_t isight_pointer(struct snd_pcm_substream *substream)
439{
440	struct isight *isight = substream->private_data;
441
442	return ACCESS_ONCE(isight->buffer_pointer);
443}
444
445static int isight_create_pcm(struct isight *isight)
446{
447	static struct snd_pcm_ops ops = {
448		.open      = isight_open,
449		.close     = isight_close,
450		.ioctl     = snd_pcm_lib_ioctl,
451		.hw_params = isight_hw_params,
452		.hw_free   = isight_hw_free,
453		.prepare   = isight_prepare,
454		.trigger   = isight_trigger,
455		.pointer   = isight_pointer,
456		.page      = snd_pcm_lib_get_vmalloc_page,
457		.mmap      = snd_pcm_lib_mmap_vmalloc,
458	};
459	struct snd_pcm *pcm;
460	int err;
461
462	err = snd_pcm_new(isight->card, "iSight", 0, 0, 1, &pcm);
463	if (err < 0)
464		return err;
465	pcm->private_data = isight;
466	strcpy(pcm->name, "iSight");
467	isight->pcm = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
468	isight->pcm->ops = &ops;
469
470	return 0;
471}
472
473static int isight_gain_info(struct snd_kcontrol *ctl,
474			    struct snd_ctl_elem_info *info)
475{
476	struct isight *isight = ctl->private_data;
477
478	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
479	info->count = 1;
480	info->value.integer.min = isight->gain_min;
481	info->value.integer.max = isight->gain_max;
482
483	return 0;
484}
485
486static int isight_gain_get(struct snd_kcontrol *ctl,
487			   struct snd_ctl_elem_value *value)
488{
489	struct isight *isight = ctl->private_data;
490	__be32 gain;
491	int err;
492
493	err = reg_read(isight, REG_GAIN, &gain);
494	if (err < 0)
495		return err;
496
497	value->value.integer.value[0] = (s32)be32_to_cpu(gain);
498
499	return 0;
500}
501
502static int isight_gain_put(struct snd_kcontrol *ctl,
503			   struct snd_ctl_elem_value *value)
504{
505	struct isight *isight = ctl->private_data;
506
507	if (value->value.integer.value[0] < isight->gain_min ||
508	    value->value.integer.value[0] > isight->gain_max)
509		return -EINVAL;
510
511	return reg_write(isight, REG_GAIN,
512			 cpu_to_be32(value->value.integer.value[0]));
513}
514
515static int isight_mute_get(struct snd_kcontrol *ctl,
516			   struct snd_ctl_elem_value *value)
517{
518	struct isight *isight = ctl->private_data;
519	__be32 mute;
520	int err;
521
522	err = reg_read(isight, REG_MUTE, &mute);
523	if (err < 0)
524		return err;
525
526	value->value.integer.value[0] = !mute;
527
528	return 0;
529}
530
531static int isight_mute_put(struct snd_kcontrol *ctl,
532			   struct snd_ctl_elem_value *value)
533{
534	struct isight *isight = ctl->private_data;
535
536	return reg_write(isight, REG_MUTE,
537			 (__force __be32)!value->value.integer.value[0]);
538}
539
540static int isight_create_mixer(struct isight *isight)
541{
542	static const struct snd_kcontrol_new gain_control = {
543		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
544		.name = "Mic Capture Volume",
545		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
546			  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
547		.info = isight_gain_info,
548		.get = isight_gain_get,
549		.put = isight_gain_put,
550	};
551	static const struct snd_kcontrol_new mute_control = {
552		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
553		.name = "Mic Capture Switch",
554		.info = snd_ctl_boolean_mono_info,
555		.get = isight_mute_get,
556		.put = isight_mute_put,
557	};
558	__be32 value;
559	struct snd_kcontrol *ctl;
560	int err;
561
562	err = reg_read(isight, REG_GAIN_RAW_START, &value);
563	if (err < 0)
564		return err;
565	isight->gain_min = be32_to_cpu(value);
566
567	err = reg_read(isight, REG_GAIN_RAW_END, &value);
568	if (err < 0)
569		return err;
570	isight->gain_max = be32_to_cpu(value);
571
572	isight->gain_tlv[0] = SNDRV_CTL_TLVT_DB_MINMAX;
573	isight->gain_tlv[1] = 2 * sizeof(unsigned int);
574
575	err = reg_read(isight, REG_GAIN_DB_START, &value);
576	if (err < 0)
577		return err;
578	isight->gain_tlv[2] = (s32)be32_to_cpu(value) * 100;
579
580	err = reg_read(isight, REG_GAIN_DB_END, &value);
581	if (err < 0)
582		return err;
583	isight->gain_tlv[3] = (s32)be32_to_cpu(value) * 100;
584
585	ctl = snd_ctl_new1(&gain_control, isight);
586	if (ctl)
587		ctl->tlv.p = isight->gain_tlv;
588	err = snd_ctl_add(isight->card, ctl);
589	if (err < 0)
590		return err;
591
592	err = snd_ctl_add(isight->card, snd_ctl_new1(&mute_control, isight));
593	if (err < 0)
594		return err;
595
596	return 0;
597}
598
599static void isight_card_free(struct snd_card *card)
600{
601	struct isight *isight = card->private_data;
602
603	fw_iso_resources_destroy(&isight->resources);
604	fw_unit_put(isight->unit);
605	mutex_destroy(&isight->mutex);
606}
607
608static u64 get_unit_base(struct fw_unit *unit)
609{
610	struct fw_csr_iterator i;
611	int key, value;
612
613	fw_csr_iterator_init(&i, unit->directory);
614	while (fw_csr_iterator_next(&i, &key, &value))
615		if (key == CSR_OFFSET)
616			return CSR_REGISTER_BASE + value * 4;
617	return 0;
618}
619
620static int isight_probe(struct fw_unit *unit,
621			const struct ieee1394_device_id *id)
622{
623	struct fw_device *fw_dev = fw_parent_device(unit);
624	struct snd_card *card;
625	struct isight *isight;
626	int err;
627
628	err = snd_card_new(&unit->device, -1, NULL, THIS_MODULE,
629			   sizeof(*isight), &card);
630	if (err < 0)
631		return err;
632
633	isight = card->private_data;
634	isight->card = card;
635	mutex_init(&isight->mutex);
636	isight->unit = fw_unit_get(unit);
637	isight->device = fw_dev;
638	isight->audio_base = get_unit_base(unit);
639	if (!isight->audio_base) {
640		dev_err(&unit->device, "audio unit base not found\n");
641		err = -ENXIO;
642		goto err_unit;
643	}
644	fw_iso_resources_init(&isight->resources, unit);
645
646	card->private_free = isight_card_free;
647
648	strcpy(card->driver, "iSight");
649	strcpy(card->shortname, "Apple iSight");
650	snprintf(card->longname, sizeof(card->longname),
651		 "Apple iSight (GUID %08x%08x) at %s, S%d",
652		 fw_dev->config_rom[3], fw_dev->config_rom[4],
653		 dev_name(&unit->device), 100 << fw_dev->max_speed);
654	strcpy(card->mixername, "iSight");
655
656	err = isight_create_pcm(isight);
657	if (err < 0)
658		goto error;
659
660	err = isight_create_mixer(isight);
661	if (err < 0)
662		goto error;
663
664	err = snd_card_register(card);
665	if (err < 0)
666		goto error;
667
668	dev_set_drvdata(&unit->device, isight);
669
670	return 0;
671
672err_unit:
673	fw_unit_put(isight->unit);
674	mutex_destroy(&isight->mutex);
675error:
676	snd_card_free(card);
677	return err;
678}
679
680static void isight_bus_reset(struct fw_unit *unit)
681{
682	struct isight *isight = dev_get_drvdata(&unit->device);
683
684	if (fw_iso_resources_update(&isight->resources) < 0) {
685		isight_pcm_abort(isight);
686
687		mutex_lock(&isight->mutex);
688		isight_stop_streaming(isight);
689		mutex_unlock(&isight->mutex);
690	}
691}
692
693static void isight_remove(struct fw_unit *unit)
694{
695	struct isight *isight = dev_get_drvdata(&unit->device);
696
697	isight_pcm_abort(isight);
698
699	snd_card_disconnect(isight->card);
700
701	mutex_lock(&isight->mutex);
702	isight_stop_streaming(isight);
703	mutex_unlock(&isight->mutex);
704
705	snd_card_free_when_closed(isight->card);
706}
707
708static const struct ieee1394_device_id isight_id_table[] = {
709	{
710		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
711				IEEE1394_MATCH_VERSION,
712		.specifier_id = OUI_APPLE,
713		.version      = SW_ISIGHT_AUDIO,
714	},
715	{ }
716};
717MODULE_DEVICE_TABLE(ieee1394, isight_id_table);
718
719static struct fw_driver isight_driver = {
720	.driver   = {
721		.owner	= THIS_MODULE,
722		.name	= KBUILD_MODNAME,
723		.bus	= &fw_bus_type,
724	},
725	.probe    = isight_probe,
726	.update   = isight_bus_reset,
727	.remove   = isight_remove,
728	.id_table = isight_id_table,
729};
730
731static int __init alsa_isight_init(void)
732{
733	return driver_register(&isight_driver.driver);
734}
735
736static void __exit alsa_isight_exit(void)
737{
738	driver_unregister(&isight_driver.driver);
739}
740
741module_init(alsa_isight_init);
742module_exit(alsa_isight_exit);
743