1 // SPDX-License-Identifier: GPL-2.0
2 // ff-protocol-latter - a part of driver for RME Fireface series
3 //
4 // Copyright (c) 2019 Takashi Sakamoto
5 //
6 // Licensed under the terms of the GNU General Public License, version 2.
7 
8 #include <linux/delay.h>
9 
10 #include "ff.h"
11 
12 #define LATTER_STF		0xffff00000004ULL
13 #define LATTER_ISOC_CHANNELS	0xffff00000008ULL
14 #define LATTER_ISOC_START	0xffff0000000cULL
15 #define LATTER_FETCH_MODE	0xffff00000010ULL
16 #define LATTER_SYNC_STATUS	0x0000801c0000ULL
17 
18 static int parse_clock_bits(u32 data, unsigned int *rate,
19 			    enum snd_ff_clock_src *src,
20 			    enum snd_ff_unit_version unit_version)
21 {
22 	static const struct {
23 		unsigned int rate;
24 		u32 flag;
25 	} *rate_entry, rate_entries[] = {
26 		{ 32000,	0x00000000, },
27 		{ 44100,	0x01000000, },
28 		{ 48000,	0x02000000, },
29 		{ 64000,	0x04000000, },
30 		{ 88200,	0x05000000, },
31 		{ 96000,	0x06000000, },
32 		{ 128000,	0x08000000, },
33 		{ 176400,	0x09000000, },
34 		{ 192000,	0x0a000000, },
35 	};
36 	static const struct {
37 		enum snd_ff_clock_src src;
38 		u32 flag;
39 	} *clk_entry, clk_entries[] = {
40 		{ SND_FF_CLOCK_SRC_SPDIF,	0x00000200, },
41 		{ SND_FF_CLOCK_SRC_ADAT1,	0x00000400, },
42 		{ SND_FF_CLOCK_SRC_WORD,	0x00000600, },
43 		{ SND_FF_CLOCK_SRC_INTERNAL,	0x00000e00, },
44 	};
45 	int i;
46 
47 	if (unit_version != SND_FF_UNIT_VERSION_UCX) {
48 		// e.g. 0x00fe0f20 but expected 0x00eff002.
49 		data = ((data & 0xf0f0f0f0) >> 4) | ((data & 0x0f0f0f0f) << 4);
50 	}
51 
52 	for (i = 0; i < ARRAY_SIZE(rate_entries); ++i) {
53 		rate_entry = rate_entries + i;
54 		if ((data & 0x0f000000) == rate_entry->flag) {
55 			*rate = rate_entry->rate;
56 			break;
57 		}
58 	}
59 	if (i == ARRAY_SIZE(rate_entries))
60 		return -EIO;
61 
62 	for (i = 0; i < ARRAY_SIZE(clk_entries); ++i) {
63 		clk_entry = clk_entries + i;
64 		if ((data & 0x000e00) == clk_entry->flag) {
65 			*src = clk_entry->src;
66 			break;
67 		}
68 	}
69 	if (i == ARRAY_SIZE(clk_entries))
70 		return -EIO;
71 
72 	return 0;
73 }
74 
75 static int latter_get_clock(struct snd_ff *ff, unsigned int *rate,
76 			   enum snd_ff_clock_src *src)
77 {
78 	__le32 reg;
79 	u32 data;
80 	int err;
81 
82 	err = snd_fw_transaction(ff->unit, TCODE_READ_QUADLET_REQUEST,
83 				 LATTER_SYNC_STATUS, &reg, sizeof(reg), 0);
84 	if (err < 0)
85 		return err;
86 	data = le32_to_cpu(reg);
87 
88 	return parse_clock_bits(data, rate, src, ff->unit_version);
89 }
90 
91 static int latter_switch_fetching_mode(struct snd_ff *ff, bool enable)
92 {
93 	u32 data;
94 	__le32 reg;
95 
96 	if (enable)
97 		data = 0x00000000;
98 	else
99 		data = 0xffffffff;
100 	reg = cpu_to_le32(data);
101 
102 	return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
103 				  LATTER_FETCH_MODE, &reg, sizeof(reg), 0);
104 }
105 
106 static int latter_allocate_resources(struct snd_ff *ff, unsigned int rate)
107 {
108 	enum snd_ff_stream_mode mode;
109 	unsigned int code;
110 	__le32 reg;
111 	unsigned int count;
112 	int i;
113 	int err;
114 
115 	// Set the number of data blocks transferred in a second.
116 	if (rate % 48000 == 0)
117 		code = 0x04;
118 	else if (rate % 44100 == 0)
119 		code = 0x02;
120 	else if (rate % 32000 == 0)
121 		code = 0x00;
122 	else
123 		return -EINVAL;
124 
125 	if (rate >= 64000 && rate < 128000)
126 		code |= 0x08;
127 	else if (rate >= 128000)
128 		code |= 0x10;
129 
130 	reg = cpu_to_le32(code);
131 	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
132 				 LATTER_STF, &reg, sizeof(reg), 0);
133 	if (err < 0)
134 		return err;
135 
136 	// Confirm to shift transmission clock.
137 	count = 0;
138 	while (count++ < 10) {
139 		unsigned int curr_rate;
140 		enum snd_ff_clock_src src;
141 
142 		err = latter_get_clock(ff, &curr_rate, &src);
143 		if (err < 0)
144 			return err;
145 
146 		if (curr_rate == rate)
147 			break;
148 	}
149 	if (count > 10)
150 		return -ETIMEDOUT;
151 
152 	for (i = 0; i < ARRAY_SIZE(amdtp_rate_table); ++i) {
153 		if (rate == amdtp_rate_table[i])
154 			break;
155 	}
156 	if (i == ARRAY_SIZE(amdtp_rate_table))
157 		return -EINVAL;
158 
159 	err = snd_ff_stream_get_multiplier_mode(i, &mode);
160 	if (err < 0)
161 		return err;
162 
163 	// Keep resources for in-stream.
164 	ff->tx_resources.channels_mask = 0x00000000000000ffuLL;
165 	err = fw_iso_resources_allocate(&ff->tx_resources,
166 			amdtp_stream_get_max_payload(&ff->tx_stream),
167 			fw_parent_device(ff->unit)->max_speed);
168 	if (err < 0)
169 		return err;
170 
171 	// Keep resources for out-stream.
172 	ff->rx_resources.channels_mask = 0x00000000000000ffuLL;
173 	err = fw_iso_resources_allocate(&ff->rx_resources,
174 			amdtp_stream_get_max_payload(&ff->rx_stream),
175 			fw_parent_device(ff->unit)->max_speed);
176 	if (err < 0)
177 		fw_iso_resources_free(&ff->tx_resources);
178 
179 	return err;
180 }
181 
182 static int latter_begin_session(struct snd_ff *ff, unsigned int rate)
183 {
184 	unsigned int generation = ff->rx_resources.generation;
185 	unsigned int flag;
186 	u32 data;
187 	__le32 reg;
188 	int err;
189 
190 	if (ff->unit_version == SND_FF_UNIT_VERSION_UCX) {
191 		// For Fireface UCX. Always use the maximum number of data
192 		// channels in data block of packet.
193 		if (rate >= 32000 && rate <= 48000)
194 			flag = 0x92;
195 		else if (rate >= 64000 && rate <= 96000)
196 			flag = 0x8e;
197 		else if (rate >= 128000 && rate <= 192000)
198 			flag = 0x8c;
199 		else
200 			return -EINVAL;
201 	} else {
202 		// For Fireface UFX and 802. Due to bandwidth limitation on
203 		// IEEE 1394a (400 Mbps), Analog 1-12 and AES are available
204 		// without any ADAT at quadruple speed.
205 		if (rate >= 32000 && rate <= 48000)
206 			flag = 0x9e;
207 		else if (rate >= 64000 && rate <= 96000)
208 			flag = 0x96;
209 		else if (rate >= 128000 && rate <= 192000)
210 			flag = 0x8e;
211 		else
212 			return -EINVAL;
213 	}
214 
215 	if (generation != fw_parent_device(ff->unit)->card->generation) {
216 		err = fw_iso_resources_update(&ff->tx_resources);
217 		if (err < 0)
218 			return err;
219 
220 		err = fw_iso_resources_update(&ff->rx_resources);
221 		if (err < 0)
222 			return err;
223 	}
224 
225 	data = (ff->tx_resources.channel << 8) | ff->rx_resources.channel;
226 	reg = cpu_to_le32(data);
227 	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
228 				 LATTER_ISOC_CHANNELS, &reg, sizeof(reg), 0);
229 	if (err < 0)
230 		return err;
231 
232 	reg = cpu_to_le32(flag);
233 	return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
234 				  LATTER_ISOC_START, &reg, sizeof(reg), 0);
235 }
236 
237 static void latter_finish_session(struct snd_ff *ff)
238 {
239 	__le32 reg;
240 
241 	reg = cpu_to_le32(0x00000000);
242 	snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
243 			   LATTER_ISOC_START, &reg, sizeof(reg), 0);
244 }
245 
246 static void latter_dump_status(struct snd_ff *ff, struct snd_info_buffer *buffer)
247 {
248 	static const struct {
249 		char *const label;
250 		u32 locked_mask;
251 		u32 synced_mask;
252 	} *clk_entry, clk_entries[] = {
253 		{ "S/PDIF",	0x00000001, 0x00000010, },
254 		{ "ADAT",	0x00000002, 0x00000020, },
255 		{ "WDClk",	0x00000004, 0x00000040, },
256 	};
257 	__le32 reg;
258 	u32 data;
259 	unsigned int rate;
260 	enum snd_ff_clock_src src;
261 	const char *label;
262 	int i;
263 	int err;
264 
265 	err = snd_fw_transaction(ff->unit, TCODE_READ_QUADLET_REQUEST,
266 				 LATTER_SYNC_STATUS, &reg, sizeof(reg), 0);
267 	if (err < 0)
268 		return;
269 	data = le32_to_cpu(reg);
270 
271 	snd_iprintf(buffer, "External source detection:\n");
272 
273 	for (i = 0; i < ARRAY_SIZE(clk_entries); ++i) {
274 		clk_entry = clk_entries + i;
275 		snd_iprintf(buffer, "%s: ", clk_entry->label);
276 		if (data & clk_entry->locked_mask) {
277 			if (data & clk_entry->synced_mask)
278 				snd_iprintf(buffer, "sync\n");
279 			else
280 				snd_iprintf(buffer, "lock\n");
281 		} else {
282 			snd_iprintf(buffer, "none\n");
283 		}
284 	}
285 
286 	err = parse_clock_bits(data, &rate, &src, ff->unit_version);
287 	if (err < 0)
288 		return;
289 	label = snd_ff_proc_get_clk_label(src);
290 	if (!label)
291 		return;
292 
293 	snd_iprintf(buffer, "Referred clock: %s %d\n", label, rate);
294 }
295 
296 // NOTE: transactions are transferred within 0x00-0x7f in allocated range of
297 // address. This seems to be for check of discontinuity in receiver side.
298 //
299 // Like Fireface 400, drivers can select one of 4 options for lower 4 bytes of
300 // destination address by bit flags in quadlet register (little endian) at
301 // 0x'ffff'0000'0014:
302 //
303 // bit flags: offset of destination address
304 // - 0x00002000: 0x'....'....'0000'0000
305 // - 0x00004000: 0x'....'....'0000'0080
306 // - 0x00008000: 0x'....'....'0000'0100
307 // - 0x00010000: 0x'....'....'0000'0180
308 //
309 // Drivers can suppress the device to transfer asynchronous transactions by
310 // clear these bit flags.
311 //
312 // Actually, the register is write-only and includes the other settings such as
313 // input attenuation. This driver allocates for the first option
314 // (0x'....'....'0000'0000) and expects userspace application to configure the
315 // register for it.
316 static void latter_handle_midi_msg(struct snd_ff *ff, unsigned int offset,
317 				   __le32 *buf, size_t length)
318 {
319 	u32 data = le32_to_cpu(*buf);
320 	unsigned int index = (data & 0x000000f0) >> 4;
321 	u8 byte[3];
322 	struct snd_rawmidi_substream *substream;
323 	unsigned int len;
324 
325 	if (index >= ff->spec->midi_in_ports)
326 		return;
327 
328 	switch (data & 0x0000000f) {
329 	case 0x00000008:
330 	case 0x00000009:
331 	case 0x0000000a:
332 	case 0x0000000b:
333 	case 0x0000000e:
334 		len = 3;
335 		break;
336 	case 0x0000000c:
337 	case 0x0000000d:
338 		len = 2;
339 		break;
340 	default:
341 		len = data & 0x00000003;
342 		if (len == 0)
343 			len = 3;
344 		break;
345 	}
346 
347 	byte[0] = (data & 0x0000ff00) >> 8;
348 	byte[1] = (data & 0x00ff0000) >> 16;
349 	byte[2] = (data & 0xff000000) >> 24;
350 
351 	substream = READ_ONCE(ff->tx_midi_substreams[index]);
352 	if (substream)
353 		snd_rawmidi_receive(substream, byte, len);
354 }
355 
356 /*
357  * When return minus value, given argument is not MIDI status.
358  * When return 0, given argument is a beginning of system exclusive.
359  * When return the others, given argument is MIDI data.
360  */
361 static inline int calculate_message_bytes(u8 status)
362 {
363 	switch (status) {
364 	case 0xf6:	/* Tune request. */
365 	case 0xf8:	/* Timing clock. */
366 	case 0xfa:	/* Start. */
367 	case 0xfb:	/* Continue. */
368 	case 0xfc:	/* Stop. */
369 	case 0xfe:	/* Active sensing. */
370 	case 0xff:	/* System reset. */
371 		return 1;
372 	case 0xf1:	/* MIDI time code quarter frame. */
373 	case 0xf3:	/* Song select. */
374 		return 2;
375 	case 0xf2:	/* Song position pointer. */
376 		return 3;
377 	case 0xf0:	/* Exclusive. */
378 		return 0;
379 	case 0xf7:	/* End of exclusive. */
380 		break;
381 	case 0xf4:	/* Undefined. */
382 	case 0xf5:	/* Undefined. */
383 	case 0xf9:	/* Undefined. */
384 	case 0xfd:	/* Undefined. */
385 		break;
386 	default:
387 		switch (status & 0xf0) {
388 		case 0x80:	/* Note on. */
389 		case 0x90:	/* Note off. */
390 		case 0xa0:	/* Polyphonic key pressure. */
391 		case 0xb0:	/* Control change and Mode change. */
392 		case 0xe0:	/* Pitch bend change. */
393 			return 3;
394 		case 0xc0:	/* Program change. */
395 		case 0xd0:	/* Channel pressure. */
396 			return 2;
397 		default:
398 		break;
399 		}
400 	break;
401 	}
402 
403 	return -EINVAL;
404 }
405 
406 static int latter_fill_midi_msg(struct snd_ff *ff,
407 				struct snd_rawmidi_substream *substream,
408 				unsigned int port)
409 {
410 	u32 data = {0};
411 	u8 *buf = (u8 *)&data;
412 	int consumed;
413 
414 	buf[0] = port << 4;
415 	consumed = snd_rawmidi_transmit_peek(substream, buf + 1, 3);
416 	if (consumed <= 0)
417 		return consumed;
418 
419 	if (!ff->on_sysex[port]) {
420 		if (buf[1] != 0xf0) {
421 			if (consumed < calculate_message_bytes(buf[1]))
422 				return 0;
423 		} else {
424 			// The beginning of exclusives.
425 			ff->on_sysex[port] = true;
426 		}
427 
428 		buf[0] |= consumed;
429 	} else {
430 		if (buf[1] != 0xf7) {
431 			if (buf[2] == 0xf7 || buf[3] == 0xf7) {
432 				// Transfer end code at next time.
433 				consumed -= 1;
434 			}
435 
436 			buf[0] |= consumed;
437 		} else {
438 			// The end of exclusives.
439 			ff->on_sysex[port] = false;
440 			consumed = 1;
441 			buf[0] |= 0x0f;
442 		}
443 	}
444 
445 	ff->msg_buf[port][0] = cpu_to_le32(data);
446 	ff->rx_bytes[port] = consumed;
447 
448 	return 1;
449 }
450 
451 const struct snd_ff_protocol snd_ff_protocol_latter = {
452 	.handle_midi_msg	= latter_handle_midi_msg,
453 	.fill_midi_msg		= latter_fill_midi_msg,
454 	.get_clock		= latter_get_clock,
455 	.switch_fetching_mode	= latter_switch_fetching_mode,
456 	.allocate_resources	= latter_allocate_resources,
457 	.begin_session		= latter_begin_session,
458 	.finish_session		= latter_finish_session,
459 	.dump_status		= latter_dump_status,
460 };
461