1// SPDX-License-Identifier: GPL-2.0
2// ff-protocol-latter.c - a part of driver for RME Fireface series
3//
4// Copyright (c) 2019 Takashi Sakamoto
5
6#include <linux/delay.h>
7
8#include "ff.h"
9
10#define LATTER_STF		0xffff00000004ULL
11#define LATTER_ISOC_CHANNELS	0xffff00000008ULL
12#define LATTER_ISOC_START	0xffff0000000cULL
13#define LATTER_FETCH_MODE	0xffff00000010ULL
14#define LATTER_SYNC_STATUS	0x0000801c0000ULL
15
16// The content of sync status register differs between models.
17//
18// Fireface UCX:
19//  0xf0000000: (unidentified)
20//  0x0f000000: effective rate of sampling clock
21//  0x00f00000: detected rate of word clock on BNC interface
22//  0x000f0000: detected rate of ADAT or S/PDIF on optical interface
23//  0x0000f000: detected rate of S/PDIF on coaxial interface
24//  0x00000e00: effective source of sampling clock
25//    0x00000e00: Internal
26//    0x00000800: (unidentified)
27//    0x00000600: Word clock on BNC interface
28//    0x00000400: ADAT on optical interface
29//    0x00000200: S/PDIF on coaxial or optical interface
30//  0x00000100: Optical interface is used for ADAT signal
31//  0x00000080: (unidentified)
32//  0x00000040: Synchronized to word clock on BNC interface
33//  0x00000020: Synchronized to ADAT or S/PDIF on optical interface
34//  0x00000010: Synchronized to S/PDIF on coaxial interface
35//  0x00000008: (unidentified)
36//  0x00000004: Lock word clock on BNC interface
37//  0x00000002: Lock ADAT or S/PDIF on optical interface
38//  0x00000001: Lock S/PDIF on coaxial interface
39//
40// Fireface 802 (and perhaps UFX):
41//   0xf0000000: effective rate of sampling clock
42//   0x0f000000: detected rate of ADAT-B on 2nd optical interface
43//   0x00f00000: detected rate of ADAT-A on 1st optical interface
44//   0x000f0000: detected rate of AES/EBU on XLR or coaxial interface
45//   0x0000f000: detected rate of word clock on BNC interface
46//   0x00000e00: effective source of sampling clock
47//     0x00000e00: internal
48//     0x00000800: ADAT-B
49//     0x00000600: ADAT-A
50//     0x00000400: AES/EBU
51//     0x00000200: Word clock
52//   0x00000080: Synchronized to ADAT-B on 2nd optical interface
53//   0x00000040: Synchronized to ADAT-A on 1st optical interface
54//   0x00000020: Synchronized to AES/EBU on XLR or 2nd optical interface
55//   0x00000010: Synchronized to word clock on BNC interface
56//   0x00000008: Lock ADAT-B on 2nd optical interface
57//   0x00000004: Lock ADAT-A on 1st optical interface
58//   0x00000002: Lock AES/EBU on XLR or 2nd optical interface
59//   0x00000001: Lock word clock on BNC interface
60//
61// The pattern for rate bits:
62//   0x00: 32.0 kHz
63//   0x01: 44.1 kHz
64//   0x02: 48.0 kHz
65//   0x04: 64.0 kHz
66//   0x05: 88.2 kHz
67//   0x06: 96.0 kHz
68//   0x08: 128.0 kHz
69//   0x09: 176.4 kHz
70//   0x0a: 192.0 kHz
71static int parse_clock_bits(u32 data, unsigned int *rate,
72			    enum snd_ff_clock_src *src,
73			    enum snd_ff_unit_version unit_version)
74{
75	static const struct {
76		unsigned int rate;
77		u32 flag;
78	} *rate_entry, rate_entries[] = {
79		{ 32000,	0x00, },
80		{ 44100,	0x01, },
81		{ 48000,	0x02, },
82		{ 64000,	0x04, },
83		{ 88200,	0x05, },
84		{ 96000,	0x06, },
85		{ 128000,	0x08, },
86		{ 176400,	0x09, },
87		{ 192000,	0x0a, },
88	};
89	static const struct {
90		enum snd_ff_clock_src src;
91		u32 flag;
92	} *clk_entry, *clk_entries, ucx_clk_entries[] = {
93		{ SND_FF_CLOCK_SRC_SPDIF,	0x00000200, },
94		{ SND_FF_CLOCK_SRC_ADAT1,	0x00000400, },
95		{ SND_FF_CLOCK_SRC_WORD,	0x00000600, },
96		{ SND_FF_CLOCK_SRC_INTERNAL,	0x00000e00, },
97	}, ufx_ff802_clk_entries[] = {
98		{ SND_FF_CLOCK_SRC_WORD,	0x00000200, },
99		{ SND_FF_CLOCK_SRC_SPDIF,	0x00000400, },
100		{ SND_FF_CLOCK_SRC_ADAT1,	0x00000600, },
101		{ SND_FF_CLOCK_SRC_ADAT2,	0x00000800, },
102		{ SND_FF_CLOCK_SRC_INTERNAL,	0x00000e00, },
103	};
104	u32 rate_bits;
105	unsigned int clk_entry_count;
106	int i;
107
108	if (unit_version == SND_FF_UNIT_VERSION_UCX) {
109		rate_bits = (data & 0x0f000000) >> 24;
110		clk_entries = ucx_clk_entries;
111		clk_entry_count = ARRAY_SIZE(ucx_clk_entries);
112	} else {
113		rate_bits = (data & 0xf0000000) >> 28;
114		clk_entries = ufx_ff802_clk_entries;
115		clk_entry_count = ARRAY_SIZE(ufx_ff802_clk_entries);
116	}
117
118	for (i = 0; i < ARRAY_SIZE(rate_entries); ++i) {
119		rate_entry = rate_entries + i;
120		if (rate_bits == rate_entry->flag) {
121			*rate = rate_entry->rate;
122			break;
123		}
124	}
125	if (i == ARRAY_SIZE(rate_entries))
126		return -EIO;
127
128	for (i = 0; i < clk_entry_count; ++i) {
129		clk_entry = clk_entries + i;
130		if ((data & 0x000e00) == clk_entry->flag) {
131			*src = clk_entry->src;
132			break;
133		}
134	}
135	if (i == clk_entry_count)
136		return -EIO;
137
138	return 0;
139}
140
141static int latter_get_clock(struct snd_ff *ff, unsigned int *rate,
142			   enum snd_ff_clock_src *src)
143{
144	__le32 reg;
145	u32 data;
146	int err;
147
148	err = snd_fw_transaction(ff->unit, TCODE_READ_QUADLET_REQUEST,
149				 LATTER_SYNC_STATUS, &reg, sizeof(reg), 0);
150	if (err < 0)
151		return err;
152	data = le32_to_cpu(reg);
153
154	return parse_clock_bits(data, rate, src, ff->unit_version);
155}
156
157static int latter_switch_fetching_mode(struct snd_ff *ff, bool enable)
158{
159	u32 data;
160	__le32 reg;
161
162	if (enable)
163		data = 0x00000000;
164	else
165		data = 0xffffffff;
166	reg = cpu_to_le32(data);
167
168	return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
169				  LATTER_FETCH_MODE, &reg, sizeof(reg), 0);
170}
171
172static int latter_allocate_resources(struct snd_ff *ff, unsigned int rate)
173{
174	enum snd_ff_stream_mode mode;
175	unsigned int code;
176	__le32 reg;
177	unsigned int count;
178	int i;
179	int err;
180
181	// Set the number of data blocks transferred in a second.
182	if (rate % 48000 == 0)
183		code = 0x04;
184	else if (rate % 44100 == 0)
185		code = 0x02;
186	else if (rate % 32000 == 0)
187		code = 0x00;
188	else
189		return -EINVAL;
190
191	if (rate >= 64000 && rate < 128000)
192		code |= 0x08;
193	else if (rate >= 128000)
194		code |= 0x10;
195
196	reg = cpu_to_le32(code);
197	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
198				 LATTER_STF, &reg, sizeof(reg), 0);
199	if (err < 0)
200		return err;
201
202	// Confirm to shift transmission clock.
203	count = 0;
204	while (count++ < 10) {
205		unsigned int curr_rate;
206		enum snd_ff_clock_src src;
207
208		err = latter_get_clock(ff, &curr_rate, &src);
209		if (err < 0)
210			return err;
211
212		if (curr_rate == rate)
213			break;
214	}
215	if (count > 10)
216		return -ETIMEDOUT;
217
218	for (i = 0; i < ARRAY_SIZE(amdtp_rate_table); ++i) {
219		if (rate == amdtp_rate_table[i])
220			break;
221	}
222	if (i == ARRAY_SIZE(amdtp_rate_table))
223		return -EINVAL;
224
225	err = snd_ff_stream_get_multiplier_mode(i, &mode);
226	if (err < 0)
227		return err;
228
229	// Keep resources for in-stream.
230	ff->tx_resources.channels_mask = 0x00000000000000ffuLL;
231	err = fw_iso_resources_allocate(&ff->tx_resources,
232			amdtp_stream_get_max_payload(&ff->tx_stream),
233			fw_parent_device(ff->unit)->max_speed);
234	if (err < 0)
235		return err;
236
237	// Keep resources for out-stream.
238	ff->rx_resources.channels_mask = 0x00000000000000ffuLL;
239	err = fw_iso_resources_allocate(&ff->rx_resources,
240			amdtp_stream_get_max_payload(&ff->rx_stream),
241			fw_parent_device(ff->unit)->max_speed);
242	if (err < 0)
243		fw_iso_resources_free(&ff->tx_resources);
244
245	return err;
246}
247
248static int latter_begin_session(struct snd_ff *ff, unsigned int rate)
249{
250	unsigned int generation = ff->rx_resources.generation;
251	unsigned int flag;
252	u32 data;
253	__le32 reg;
254	int err;
255
256	if (ff->unit_version == SND_FF_UNIT_VERSION_UCX) {
257		// For Fireface UCX. Always use the maximum number of data
258		// channels in data block of packet.
259		if (rate >= 32000 && rate <= 48000)
260			flag = 0x92;
261		else if (rate >= 64000 && rate <= 96000)
262			flag = 0x8e;
263		else if (rate >= 128000 && rate <= 192000)
264			flag = 0x8c;
265		else
266			return -EINVAL;
267	} else {
268		// For Fireface UFX and 802. Due to bandwidth limitation on
269		// IEEE 1394a (400 Mbps), Analog 1-12 and AES are available
270		// without any ADAT at quadruple speed.
271		if (rate >= 32000 && rate <= 48000)
272			flag = 0x9e;
273		else if (rate >= 64000 && rate <= 96000)
274			flag = 0x96;
275		else if (rate >= 128000 && rate <= 192000)
276			flag = 0x8e;
277		else
278			return -EINVAL;
279	}
280
281	if (generation != fw_parent_device(ff->unit)->card->generation) {
282		err = fw_iso_resources_update(&ff->tx_resources);
283		if (err < 0)
284			return err;
285
286		err = fw_iso_resources_update(&ff->rx_resources);
287		if (err < 0)
288			return err;
289	}
290
291	data = (ff->tx_resources.channel << 8) | ff->rx_resources.channel;
292	reg = cpu_to_le32(data);
293	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
294				 LATTER_ISOC_CHANNELS, &reg, sizeof(reg), 0);
295	if (err < 0)
296		return err;
297
298	reg = cpu_to_le32(flag);
299	return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
300				  LATTER_ISOC_START, &reg, sizeof(reg), 0);
301}
302
303static void latter_finish_session(struct snd_ff *ff)
304{
305	__le32 reg;
306
307	reg = cpu_to_le32(0x00000000);
308	snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
309			   LATTER_ISOC_START, &reg, sizeof(reg), 0);
310}
311
312static void latter_dump_status(struct snd_ff *ff, struct snd_info_buffer *buffer)
313{
314	static const struct {
315		char *const label;
316		u32 locked_mask;
317		u32 synced_mask;
318	} *clk_entry, *clk_entries, ucx_clk_entries[] = {
319		{ "S/PDIF",	0x00000001, 0x00000010, },
320		{ "ADAT",	0x00000002, 0x00000020, },
321		{ "WDClk",	0x00000004, 0x00000040, },
322	}, ufx_ff802_clk_entries[] = {
323		{ "WDClk",	0x00000001, 0x00000010, },
324		{ "AES/EBU",	0x00000002, 0x00000020, },
325		{ "ADAT-A",	0x00000004, 0x00000040, },
326		{ "ADAT-B",	0x00000008, 0x00000080, },
327	};
328	__le32 reg;
329	u32 data;
330	unsigned int rate;
331	enum snd_ff_clock_src src;
332	const char *label;
333	unsigned int clk_entry_count;
334	int i;
335	int err;
336
337	err = snd_fw_transaction(ff->unit, TCODE_READ_QUADLET_REQUEST,
338				 LATTER_SYNC_STATUS, &reg, sizeof(reg), 0);
339	if (err < 0)
340		return;
341	data = le32_to_cpu(reg);
342
343	snd_iprintf(buffer, "External source detection:\n");
344
345	if (ff->unit_version == SND_FF_UNIT_VERSION_UCX) {
346		clk_entries = ucx_clk_entries;
347		clk_entry_count = ARRAY_SIZE(ucx_clk_entries);
348	} else {
349		clk_entries = ufx_ff802_clk_entries;
350		clk_entry_count = ARRAY_SIZE(ufx_ff802_clk_entries);
351	}
352
353	for (i = 0; i < clk_entry_count; ++i) {
354		clk_entry = clk_entries + i;
355		snd_iprintf(buffer, "%s: ", clk_entry->label);
356		if (data & clk_entry->locked_mask) {
357			if (data & clk_entry->synced_mask)
358				snd_iprintf(buffer, "sync\n");
359			else
360				snd_iprintf(buffer, "lock\n");
361		} else {
362			snd_iprintf(buffer, "none\n");
363		}
364	}
365
366	err = parse_clock_bits(data, &rate, &src, ff->unit_version);
367	if (err < 0)
368		return;
369	label = snd_ff_proc_get_clk_label(src);
370	if (!label)
371		return;
372
373	snd_iprintf(buffer, "Referred clock: %s %d\n", label, rate);
374}
375
376// NOTE: transactions are transferred within 0x00-0x7f in allocated range of
377// address. This seems to be for check of discontinuity in receiver side.
378//
379// Like Fireface 400, drivers can select one of 4 options for lower 4 bytes of
380// destination address by bit flags in quadlet register (little endian) at
381// 0x'ffff'0000'0014:
382//
383// bit flags: offset of destination address
384// - 0x00002000: 0x'....'....'0000'0000
385// - 0x00004000: 0x'....'....'0000'0080
386// - 0x00008000: 0x'....'....'0000'0100
387// - 0x00010000: 0x'....'....'0000'0180
388//
389// Drivers can suppress the device to transfer asynchronous transactions by
390// clear these bit flags.
391//
392// Actually, the register is write-only and includes the other settings such as
393// input attenuation. This driver allocates for the first option
394// (0x'....'....'0000'0000) and expects userspace application to configure the
395// register for it.
396static void latter_handle_midi_msg(struct snd_ff *ff, unsigned int offset, const __le32 *buf,
397				   size_t length, u32 tstamp)
398{
399	u32 data = le32_to_cpu(*buf);
400	unsigned int index = (data & 0x000000f0) >> 4;
401	u8 byte[3];
402	struct snd_rawmidi_substream *substream;
403	unsigned int len;
404
405	if (index >= ff->spec->midi_in_ports)
406		return;
407
408	switch (data & 0x0000000f) {
409	case 0x00000008:
410	case 0x00000009:
411	case 0x0000000a:
412	case 0x0000000b:
413	case 0x0000000e:
414		len = 3;
415		break;
416	case 0x0000000c:
417	case 0x0000000d:
418		len = 2;
419		break;
420	default:
421		len = data & 0x00000003;
422		if (len == 0)
423			len = 3;
424		break;
425	}
426
427	byte[0] = (data & 0x0000ff00) >> 8;
428	byte[1] = (data & 0x00ff0000) >> 16;
429	byte[2] = (data & 0xff000000) >> 24;
430
431	substream = READ_ONCE(ff->tx_midi_substreams[index]);
432	if (substream)
433		snd_rawmidi_receive(substream, byte, len);
434}
435
436/*
437 * When return minus value, given argument is not MIDI status.
438 * When return 0, given argument is a beginning of system exclusive.
439 * When return the others, given argument is MIDI data.
440 */
441static inline int calculate_message_bytes(u8 status)
442{
443	switch (status) {
444	case 0xf6:	/* Tune request. */
445	case 0xf8:	/* Timing clock. */
446	case 0xfa:	/* Start. */
447	case 0xfb:	/* Continue. */
448	case 0xfc:	/* Stop. */
449	case 0xfe:	/* Active sensing. */
450	case 0xff:	/* System reset. */
451		return 1;
452	case 0xf1:	/* MIDI time code quarter frame. */
453	case 0xf3:	/* Song select. */
454		return 2;
455	case 0xf2:	/* Song position pointer. */
456		return 3;
457	case 0xf0:	/* Exclusive. */
458		return 0;
459	case 0xf7:	/* End of exclusive. */
460		break;
461	case 0xf4:	/* Undefined. */
462	case 0xf5:	/* Undefined. */
463	case 0xf9:	/* Undefined. */
464	case 0xfd:	/* Undefined. */
465		break;
466	default:
467		switch (status & 0xf0) {
468		case 0x80:	/* Note on. */
469		case 0x90:	/* Note off. */
470		case 0xa0:	/* Polyphonic key pressure. */
471		case 0xb0:	/* Control change and Mode change. */
472		case 0xe0:	/* Pitch bend change. */
473			return 3;
474		case 0xc0:	/* Program change. */
475		case 0xd0:	/* Channel pressure. */
476			return 2;
477		default:
478		break;
479		}
480	break;
481	}
482
483	return -EINVAL;
484}
485
486static int latter_fill_midi_msg(struct snd_ff *ff,
487				struct snd_rawmidi_substream *substream,
488				unsigned int port)
489{
490	u32 data = {0};
491	u8 *buf = (u8 *)&data;
492	int consumed;
493
494	buf[0] = port << 4;
495	consumed = snd_rawmidi_transmit_peek(substream, buf + 1, 3);
496	if (consumed <= 0)
497		return consumed;
498
499	if (!ff->on_sysex[port]) {
500		if (buf[1] != 0xf0) {
501			if (consumed < calculate_message_bytes(buf[1]))
502				return 0;
503		} else {
504			// The beginning of exclusives.
505			ff->on_sysex[port] = true;
506		}
507
508		buf[0] |= consumed;
509	} else {
510		if (buf[1] != 0xf7) {
511			if (buf[2] == 0xf7 || buf[3] == 0xf7) {
512				// Transfer end code at next time.
513				consumed -= 1;
514			}
515
516			buf[0] |= consumed;
517		} else {
518			// The end of exclusives.
519			ff->on_sysex[port] = false;
520			consumed = 1;
521			buf[0] |= 0x0f;
522		}
523	}
524
525	ff->msg_buf[port][0] = cpu_to_le32(data);
526	ff->rx_bytes[port] = consumed;
527
528	return 1;
529}
530
531const struct snd_ff_protocol snd_ff_protocol_latter = {
532	.handle_msg		= latter_handle_midi_msg,
533	.fill_midi_msg		= latter_fill_midi_msg,
534	.get_clock		= latter_get_clock,
535	.switch_fetching_mode	= latter_switch_fetching_mode,
536	.allocate_resources	= latter_allocate_resources,
537	.begin_session		= latter_begin_session,
538	.finish_session		= latter_finish_session,
539	.dump_status		= latter_dump_status,
540};
541