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_HEADER: 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 * @CIP_DBC_IS_PAYLOAD_QUADLETS: Available for incoming packet, and only effective with
41 * CIP_DBC_IS_END_EVENT flag. The value of dbc field is the number of accumulated quadlets
42 * in CIP payload, instead of the number of accumulated data blocks.
43 */
44enum cip_flags {
45 CIP_NONBLOCKING = 0x00,
46 CIP_BLOCKING = 0x01,
47 CIP_EMPTY_WITH_TAG0 = 0x02,
48 CIP_DBC_IS_END_EVENT = 0x04,
49 CIP_WRONG_DBS = 0x08,
50 CIP_SKIP_DBC_ZERO_CHECK = 0x10,
51 CIP_EMPTY_HAS_WRONG_DBC = 0x20,
52 CIP_JUMBO_PAYLOAD = 0x40,
53 CIP_HEADER_WITHOUT_EOH = 0x80,
54 CIP_NO_HEADER = 0x100,
55 CIP_UNALIGHED_DBC = 0x200,
56 CIP_UNAWARE_SYT = 0x400,
57 CIP_DBC_IS_PAYLOAD_QUADLETS = 0x800,
58};
59
60/**
61 * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
62 * @CIP_SFC_32000: 32,000 data blocks
63 * @CIP_SFC_44100: 44,100 data blocks
64 * @CIP_SFC_48000: 48,000 data blocks
65 * @CIP_SFC_88200: 88,200 data blocks
66 * @CIP_SFC_96000: 96,000 data blocks
67 * @CIP_SFC_176400: 176,400 data blocks
68 * @CIP_SFC_192000: 192,000 data blocks
69 * @CIP_SFC_COUNT: the number of supported SFCs
70 *
71 * These values are used to show nominal Sampling Frequency Code in
72 * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
73 * this code means the number of events per second. Actually the code
74 * represents the number of data blocks transferred per second in an AMDTP
75 * stream.
76 *
77 * In IEC 61883-6:2005, some extensions were added to support more types of
78 * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
79 * different depending on the types.
80 *
81 * Currently our implementation is compatible with IEC 61883-6:2002.
82 */
83enum cip_sfc {
84 CIP_SFC_32000 = 0,
85 CIP_SFC_44100 = 1,
86 CIP_SFC_48000 = 2,
87 CIP_SFC_88200 = 3,
88 CIP_SFC_96000 = 4,
89 CIP_SFC_176400 = 5,
90 CIP_SFC_192000 = 6,
91 CIP_SFC_COUNT
92};
93
94struct fw_unit;
95struct fw_iso_context;
96struct snd_pcm_substream;
97struct snd_pcm_runtime;
98
99enum amdtp_stream_direction {
100 AMDTP_OUT_STREAM = 0,
101 AMDTP_IN_STREAM
102};
103
104struct pkt_desc {
105 u32 cycle;
106 u32 syt;
107 unsigned int data_blocks;
108 unsigned int data_block_counter;
109 __be32 *ctx_payload;
110 struct list_head link;
111};
112
113struct amdtp_stream;
114typedef void (*amdtp_stream_process_ctx_payloads_t)(struct amdtp_stream *s,
115 const struct pkt_desc *desc,
116 unsigned int count,
117 struct snd_pcm_substream *pcm);
118
119struct amdtp_domain;
120struct amdtp_stream {
121 struct fw_unit *unit;
122 // The combination of cip_flags enumeration-constants.
123 unsigned int flags;
124 enum amdtp_stream_direction direction;
125 struct mutex mutex;
126
127 /* For packet processing. */
128 struct fw_iso_context *context;
129 struct iso_packets_buffer buffer;
130 unsigned int queue_size;
131 int packet_index;
132 struct pkt_desc *packet_descs;
133 struct list_head packet_descs_list;
134 struct pkt_desc *packet_descs_cursor;
135 int tag;
136 union {
137 struct {
138 unsigned int ctx_header_size;
139
140 // limit for payload of iso packet.
141 unsigned int max_ctx_payload_length;
142
143 // For quirks of CIP headers.
144 // Fixed interval of dbc between previos/current
145 // packets.
146 unsigned int dbc_interval;
147
148 // The device starts multiplexing events to the packet.
149 bool event_starts;
150
151 struct {
152 struct seq_desc *descs;
153 unsigned int size;
154 unsigned int pos;
155 } cache;
156 } tx;
157 struct {
158 // To generate CIP header.
159 unsigned int fdf;
160
161 // To generate constant hardware IRQ.
162 unsigned int event_count;
163
164 // To calculate CIP data blocks and tstamp.
165 struct {
166 struct seq_desc *descs;
167 unsigned int size;
168 unsigned int pos;
169 } seq;
170
171 unsigned int data_block_state;
172 unsigned int syt_offset_state;
173 unsigned int last_syt_offset;
174
175 struct amdtp_stream *replay_target;
176 unsigned int cache_pos;
177 } rx;
178 } ctx_data;
179
180 /* For CIP headers. */
181 unsigned int source_node_id_field;
182 unsigned int data_block_quadlets;
183 unsigned int data_block_counter;
184 unsigned int sph;
185 unsigned int fmt;
186
187 // Internal flags.
188 unsigned int transfer_delay;
189 enum cip_sfc sfc;
190 unsigned int syt_interval;
191
192 /* For a PCM substream processing. */
193 struct snd_pcm_substream *pcm;
194 struct work_struct period_work;
195 snd_pcm_uframes_t pcm_buffer_pointer;
196 unsigned int pcm_period_pointer;
197 unsigned int pcm_frame_multiplier;
198
199 // To start processing content of packets at the same cycle in several contexts for
200 // each direction.
201 bool ready_processing;
202 wait_queue_head_t ready_wait;
203 unsigned int next_cycle;
204
205 /* For backends to process data blocks. */
206 void *protocol;
207 amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
208
209 // For domain.
210 int channel;
211 int speed;
212 struct list_head list;
213 struct amdtp_domain *domain;
214};
215
216int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
217 enum amdtp_stream_direction dir, unsigned int flags,
218 unsigned int fmt,
219 amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
220 unsigned int protocol_size);
221void amdtp_stream_destroy(struct amdtp_stream *s);
222
223int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
224 unsigned int data_block_quadlets, unsigned int pcm_frame_multiplier);
225unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
226
227void amdtp_stream_update(struct amdtp_stream *s);
228
229int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
230 struct snd_pcm_runtime *runtime);
231
232void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
233void amdtp_stream_pcm_abort(struct amdtp_stream *s);
234
235extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
236extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
237
238/**
239 * amdtp_stream_running - check stream is running or not
240 * @s: the AMDTP stream
241 *
242 * If this function returns true, the stream is running.
243 */
244static inline bool amdtp_stream_running(struct amdtp_stream *s)
245{
246 return !IS_ERR(ptr: s->context);
247}
248
249/**
250 * amdtp_streaming_error - check for streaming error
251 * @s: the AMDTP stream
252 *
253 * If this function returns true, the stream's packet queue has stopped due to
254 * an asynchronous error.
255 */
256static inline bool amdtp_streaming_error(struct amdtp_stream *s)
257{
258 return s->packet_index < 0;
259}
260
261/**
262 * amdtp_stream_pcm_running - check PCM substream is running or not
263 * @s: the AMDTP stream
264 *
265 * If this function returns true, PCM substream in the AMDTP stream is running.
266 */
267static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
268{
269 return !!s->pcm;
270}
271
272/**
273 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
274 * @s: the AMDTP stream
275 * @pcm: the PCM device to be started, or %NULL to stop the current device
276 *
277 * Call this function on a running isochronous stream to enable the actual
278 * transmission of PCM data. This function should be called from the PCM
279 * device's .trigger callback.
280 */
281static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
282 struct snd_pcm_substream *pcm)
283{
284 WRITE_ONCE(s->pcm, pcm);
285}
286
287/**
288 * amdtp_stream_next_packet_desc - retrieve next descriptor for amdtp packet.
289 * @s: the AMDTP stream
290 * @desc: the descriptor of packet
291 *
292 * This macro computes next descriptor so that the list of descriptors behaves circular queue.
293 */
294#define amdtp_stream_next_packet_desc(s, desc) \
295 list_next_entry_circular(desc, &s->packet_descs_list, link)
296
297static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
298{
299 return sfc & 1;
300}
301
302struct seq_desc {
303 unsigned int syt_offset;
304 unsigned int data_blocks;
305};
306
307struct amdtp_domain {
308 struct list_head streams;
309
310 unsigned int events_per_period;
311 unsigned int events_per_buffer;
312
313 struct amdtp_stream *irq_target;
314
315 struct {
316 unsigned int tx_init_skip;
317 unsigned int tx_start;
318 unsigned int rx_start;
319 } processing_cycle;
320
321 struct {
322 bool enable:1;
323 bool on_the_fly:1;
324 } replay;
325};
326
327int amdtp_domain_init(struct amdtp_domain *d);
328void amdtp_domain_destroy(struct amdtp_domain *d);
329
330int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
331 int channel, int speed);
332
333int amdtp_domain_start(struct amdtp_domain *d, unsigned int tx_init_skip_cycles, bool replay_seq,
334 bool replay_on_the_fly);
335void amdtp_domain_stop(struct amdtp_domain *d);
336
337static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
338 unsigned int events_per_period,
339 unsigned int events_per_buffer)
340{
341 d->events_per_period = events_per_period;
342 d->events_per_buffer = events_per_buffer;
343
344 return 0;
345}
346
347unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
348 struct amdtp_stream *s);
349int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
350
351/**
352 * amdtp_domain_wait_ready - sleep till being ready to process packets or timeout
353 * @d: the AMDTP domain
354 * @timeout_ms: msec till timeout
355 *
356 * If this function return false, the AMDTP domain should be stopped.
357 */
358static inline bool amdtp_domain_wait_ready(struct amdtp_domain *d, unsigned int timeout_ms)
359{
360 struct amdtp_stream *s;
361
362 list_for_each_entry(s, &d->streams, list) {
363 unsigned int j = msecs_to_jiffies(m: timeout_ms);
364
365 if (wait_event_interruptible_timeout(s->ready_wait, s->ready_processing, j) <= 0)
366 return false;
367 }
368
369 return true;
370}
371
372#endif
373

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