1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
3#define SOUND_FIREWIRE_AMDTP_H_INCLUDED
4
5#include <linux/err.h>
6#include <linux/interrupt.h>
7#include <linux/mutex.h>
8#include <linux/sched.h>
9#include <sound/asound.h>
10#include "packets-buffer.h"
11
12/**
13 * enum cip_flags - describes details of the streaming protocol
14 * @CIP_NONBLOCKING: In non-blocking mode, each packet contains
15 * sample_rate/8000 samples, with rounding up or down to adjust
16 * for clock skew and left-over fractional samples. This should
17 * be used if supported by the device.
18 * @CIP_BLOCKING: In blocking mode, each packet contains either zero or
19 * SYT_INTERVAL samples, with these two types alternating so that
20 * the overall sample rate comes out right.
21 * @CIP_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
22 * @CIP_DBC_IS_END_EVENT: The value of dbc in an packet corresponds to the end
23 * of event in the packet. Out of IEC 61883.
24 * @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
25 * The value of data_block_quadlets is used instead of reported value.
26 * @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream. Packets with zero in dbc is
27 * skipped for detecting discontinuity.
28 * @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
29 * packet is wrong but the others are correct.
30 * @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
31 * packet is larger than IEC 61883-6 defines. Current implementation
32 * allows 5 times as large as IEC 61883-6 defines.
33 * @CIP_HEADER_WITHOUT_EOH: Only for in-stream. CIP Header doesn't include
34 * valid EOH.
35 * @CIP_NO_HEADERS: a lack of headers in packets
36 * @CIP_UNALIGHED_DBC: Only for in-stream. The value of dbc is not alighed to
37 * the value of current SYT_INTERVAL; e.g. initial value is not zero.
38 * @CIP_UNAWARE_SYT: For outgoing packet, the value in SYT field of CIP is 0xffff.
39 * For incoming packet, the value in SYT field of CIP is not handled.
40 */
41enum cip_flags {
42 CIP_NONBLOCKING = 0x00,
43 CIP_BLOCKING = 0x01,
44 CIP_EMPTY_WITH_TAG0 = 0x02,
45 CIP_DBC_IS_END_EVENT = 0x04,
46 CIP_WRONG_DBS = 0x08,
47 CIP_SKIP_DBC_ZERO_CHECK = 0x10,
48 CIP_EMPTY_HAS_WRONG_DBC = 0x20,
49 CIP_JUMBO_PAYLOAD = 0x40,
50 CIP_HEADER_WITHOUT_EOH = 0x80,
51 CIP_NO_HEADER = 0x100,
52 CIP_UNALIGHED_DBC = 0x200,
53 CIP_UNAWARE_SYT = 0x400,
54};
55
56/**
57 * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
58 * @CIP_SFC_32000: 32,000 data blocks
59 * @CIP_SFC_44100: 44,100 data blocks
60 * @CIP_SFC_48000: 48,000 data blocks
61 * @CIP_SFC_88200: 88,200 data blocks
62 * @CIP_SFC_96000: 96,000 data blocks
63 * @CIP_SFC_176400: 176,400 data blocks
64 * @CIP_SFC_192000: 192,000 data blocks
65 * @CIP_SFC_COUNT: the number of supported SFCs
66 *
67 * These values are used to show nominal Sampling Frequency Code in
68 * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
69 * this code means the number of events per second. Actually the code
70 * represents the number of data blocks transferred per second in an AMDTP
71 * stream.
72 *
73 * In IEC 61883-6:2005, some extensions were added to support more types of
74 * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
75 * different depending on the types.
76 *
77 * Currently our implementation is compatible with IEC 61883-6:2002.
78 */
79enum cip_sfc {
80 CIP_SFC_32000 = 0,
81 CIP_SFC_44100 = 1,
82 CIP_SFC_48000 = 2,
83 CIP_SFC_88200 = 3,
84 CIP_SFC_96000 = 4,
85 CIP_SFC_176400 = 5,
86 CIP_SFC_192000 = 6,
87 CIP_SFC_COUNT
88};
89
90struct fw_unit;
91struct fw_iso_context;
92struct snd_pcm_substream;
93struct snd_pcm_runtime;
94
95enum amdtp_stream_direction {
96 AMDTP_OUT_STREAM = 0,
97 AMDTP_IN_STREAM
98};
99
100struct pkt_desc {
101 u32 cycle;
102 u32 syt;
103 unsigned int data_blocks;
104 unsigned int data_block_counter;
105 __be32 *ctx_payload;
106 struct list_head link;
107};
108
109struct amdtp_stream;
110typedef void (*amdtp_stream_process_ctx_payloads_t)(struct amdtp_stream *s,
111 const struct pkt_desc *desc,
112 unsigned int count,
113 struct snd_pcm_substream *pcm);
114
115struct amdtp_domain;
116struct amdtp_stream {
117 struct fw_unit *unit;
118 // The combination of cip_flags enumeration-constants.
119 unsigned int flags;
120 enum amdtp_stream_direction direction;
121 struct mutex mutex;
122
123 /* For packet processing. */
124 struct fw_iso_context *context;
125 struct iso_packets_buffer buffer;
126 unsigned int queue_size;
127 int packet_index;
128 struct pkt_desc *packet_descs;
129 struct list_head packet_descs_list;
130 struct pkt_desc *packet_descs_cursor;
131 int tag;
132 union {
133 struct {
134 unsigned int ctx_header_size;
135
136 // limit for payload of iso packet.
137 unsigned int max_ctx_payload_length;
138
139 // For quirks of CIP headers.
140 // Fixed interval of dbc between previos/current
141 // packets.
142 unsigned int dbc_interval;
143
144 // The device starts multiplexing events to the packet.
145 bool event_starts;
146
147 struct {
148 struct seq_desc *descs;
149 unsigned int size;
150 unsigned int pos;
151 } cache;
152 } tx;
153 struct {
154 // To generate CIP header.
155 unsigned int fdf;
156
157 // To generate constant hardware IRQ.
158 unsigned int event_count;
159
160 // To calculate CIP data blocks and tstamp.
161 struct {
162 struct seq_desc *descs;
163 unsigned int size;
164 unsigned int pos;
165 } seq;
166
167 unsigned int data_block_state;
168 unsigned int syt_offset_state;
169 unsigned int last_syt_offset;
170
171 struct amdtp_stream *replay_target;
172 unsigned int cache_pos;
173 } rx;
174 } ctx_data;
175
176 /* For CIP headers. */
177 unsigned int source_node_id_field;
178 unsigned int data_block_quadlets;
179 unsigned int data_block_counter;
180 unsigned int sph;
181 unsigned int fmt;
182
183 // Internal flags.
184 unsigned int transfer_delay;
185 enum cip_sfc sfc;
186 unsigned int syt_interval;
187
188 /* For a PCM substream processing. */
189 struct snd_pcm_substream *pcm;
190 snd_pcm_uframes_t pcm_buffer_pointer;
191 unsigned int pcm_period_pointer;
192 unsigned int pcm_frame_multiplier;
193
194 // To start processing content of packets at the same cycle in several contexts for
195 // each direction.
196 bool ready_processing;
197 wait_queue_head_t ready_wait;
198 unsigned int next_cycle;
199
200 /* For backends to process data blocks. */
201 void *protocol;
202 amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
203
204 // For domain.
205 int channel;
206 int speed;
207 struct list_head list;
208 struct amdtp_domain *domain;
209};
210
211int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
212 enum amdtp_stream_direction dir, unsigned int flags,
213 unsigned int fmt,
214 amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
215 unsigned int protocol_size);
216void amdtp_stream_destroy(struct amdtp_stream *s);
217
218int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
219 unsigned int data_block_quadlets, unsigned int pcm_frame_multiplier);
220unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
221
222void amdtp_stream_update(struct amdtp_stream *s);
223
224int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
225 struct snd_pcm_runtime *runtime);
226
227void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
228void amdtp_stream_pcm_abort(struct amdtp_stream *s);
229
230extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
231extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
232
233/**
234 * amdtp_stream_running - check stream is running or not
235 * @s: the AMDTP stream
236 *
237 * If this function returns true, the stream is running.
238 */
239static inline bool amdtp_stream_running(struct amdtp_stream *s)
240{
241 return !IS_ERR(ptr: s->context);
242}
243
244/**
245 * amdtp_streaming_error - check for streaming error
246 * @s: the AMDTP stream
247 *
248 * If this function returns true, the stream's packet queue has stopped due to
249 * an asynchronous error.
250 */
251static inline bool amdtp_streaming_error(struct amdtp_stream *s)
252{
253 return s->packet_index < 0;
254}
255
256/**
257 * amdtp_stream_pcm_running - check PCM substream is running or not
258 * @s: the AMDTP stream
259 *
260 * If this function returns true, PCM substream in the AMDTP stream is running.
261 */
262static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
263{
264 return !!s->pcm;
265}
266
267/**
268 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
269 * @s: the AMDTP stream
270 * @pcm: the PCM device to be started, or %NULL to stop the current device
271 *
272 * Call this function on a running isochronous stream to enable the actual
273 * transmission of PCM data. This function should be called from the PCM
274 * device's .trigger callback.
275 */
276static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
277 struct snd_pcm_substream *pcm)
278{
279 WRITE_ONCE(s->pcm, pcm);
280}
281
282/**
283 * amdtp_stream_next_packet_desc - retrieve next descriptor for amdtp packet.
284 * @s: the AMDTP stream
285 * @desc: the descriptor of packet
286 *
287 * This macro computes next descriptor so that the list of descriptors behaves circular queue.
288 */
289#define amdtp_stream_next_packet_desc(s, desc) \
290 list_next_entry_circular(desc, &s->packet_descs_list, link)
291
292static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
293{
294 return sfc & 1;
295}
296
297struct seq_desc {
298 unsigned int syt_offset;
299 unsigned int data_blocks;
300};
301
302struct amdtp_domain {
303 struct list_head streams;
304
305 unsigned int events_per_period;
306 unsigned int events_per_buffer;
307
308 struct amdtp_stream *irq_target;
309
310 struct {
311 unsigned int tx_init_skip;
312 unsigned int tx_start;
313 unsigned int rx_start;
314 } processing_cycle;
315
316 struct {
317 bool enable:1;
318 bool on_the_fly:1;
319 } replay;
320};
321
322int amdtp_domain_init(struct amdtp_domain *d);
323void amdtp_domain_destroy(struct amdtp_domain *d);
324
325int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
326 int channel, int speed);
327
328int amdtp_domain_start(struct amdtp_domain *d, unsigned int tx_init_skip_cycles, bool replay_seq,
329 bool replay_on_the_fly);
330void amdtp_domain_stop(struct amdtp_domain *d);
331
332static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
333 unsigned int events_per_period,
334 unsigned int events_per_buffer)
335{
336 d->events_per_period = events_per_period;
337 d->events_per_buffer = events_per_buffer;
338
339 return 0;
340}
341
342unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
343 struct amdtp_stream *s);
344int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
345
346/**
347 * amdtp_domain_wait_ready - sleep till being ready to process packets or timeout
348 * @d: the AMDTP domain
349 * @timeout_ms: msec till timeout
350 *
351 * If this function return false, the AMDTP domain should be stopped.
352 */
353static inline bool amdtp_domain_wait_ready(struct amdtp_domain *d, unsigned int timeout_ms)
354{
355 struct amdtp_stream *s;
356
357 list_for_each_entry(s, &d->streams, list) {
358 unsigned int j = msecs_to_jiffies(m: timeout_ms);
359
360 if (wait_event_interruptible_timeout(s->ready_wait, s->ready_processing, j) <= 0)
361 return false;
362 }
363
364 return true;
365}
366
367#endif
368

source code of linux/sound/firewire/amdtp-stream.h