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};
107
108struct amdtp_stream;
109typedef unsigned int (*amdtp_stream_process_ctx_payloads_t)(
110						struct amdtp_stream *s,
111						const struct pkt_desc *desc,
112						unsigned int packets,
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 *pkt_descs;
129	int tag;
130	union {
131		struct {
132			unsigned int ctx_header_size;
133
134			// limit for payload of iso packet.
135			unsigned int max_ctx_payload_length;
136
137			// For quirks of CIP headers.
138			// Fixed interval of dbc between previos/current
139			// packets.
140			unsigned int dbc_interval;
141
142			// The device starts multiplexing events to the packet.
143			bool event_starts;
144
145			struct {
146				struct seq_desc *descs;
147				unsigned int size;
148				unsigned int tail;
149			} cache;
150		} tx;
151		struct {
152			// To generate CIP header.
153			unsigned int fdf;
154
155			// To generate constant hardware IRQ.
156			unsigned int event_count;
157
158			// To calculate CIP data blocks and tstamp.
159			struct {
160				struct seq_desc *descs;
161				unsigned int size;
162				unsigned int tail;
163				unsigned int head;
164			} seq;
165
166			unsigned int data_block_state;
167			unsigned int syt_offset_state;
168			unsigned int last_syt_offset;
169
170			struct amdtp_stream *replay_target;
171			unsigned int cache_head;
172		} rx;
173	} ctx_data;
174
175	/* For CIP headers. */
176	unsigned int source_node_id_field;
177	unsigned int data_block_quadlets;
178	unsigned int data_block_counter;
179	unsigned int sph;
180	unsigned int fmt;
181
182	// Internal flags.
183	unsigned int transfer_delay;
184	enum cip_sfc sfc;
185	unsigned int syt_interval;
186
187	/* For a PCM substream processing. */
188	struct snd_pcm_substream *pcm;
189	snd_pcm_uframes_t pcm_buffer_pointer;
190	unsigned int pcm_period_pointer;
191
192	// To start processing content of packets at the same cycle in several contexts for
193	// each direction.
194	bool ready_processing;
195	wait_queue_head_t ready_wait;
196	unsigned int next_cycle;
197
198	/* For backends to process data blocks. */
199	void *protocol;
200	amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
201
202	// For domain.
203	int channel;
204	int speed;
205	struct list_head list;
206	struct amdtp_domain *domain;
207};
208
209int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
210		      enum amdtp_stream_direction dir, unsigned int flags,
211		      unsigned int fmt,
212		      amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
213		      unsigned int protocol_size);
214void amdtp_stream_destroy(struct amdtp_stream *s);
215
216int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
217				unsigned int data_block_quadlets);
218unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
219
220void amdtp_stream_update(struct amdtp_stream *s);
221
222int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
223					struct snd_pcm_runtime *runtime);
224
225void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
226void amdtp_stream_pcm_abort(struct amdtp_stream *s);
227
228extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
229extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
230
231/**
232 * amdtp_stream_running - check stream is running or not
233 * @s: the AMDTP stream
234 *
235 * If this function returns true, the stream is running.
236 */
237static inline bool amdtp_stream_running(struct amdtp_stream *s)
238{
239	return !IS_ERR(s->context);
240}
241
242/**
243 * amdtp_streaming_error - check for streaming error
244 * @s: the AMDTP stream
245 *
246 * If this function returns true, the stream's packet queue has stopped due to
247 * an asynchronous error.
248 */
249static inline bool amdtp_streaming_error(struct amdtp_stream *s)
250{
251	return s->packet_index < 0;
252}
253
254/**
255 * amdtp_stream_pcm_running - check PCM substream is running or not
256 * @s: the AMDTP stream
257 *
258 * If this function returns true, PCM substream in the AMDTP stream is running.
259 */
260static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
261{
262	return !!s->pcm;
263}
264
265/**
266 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
267 * @s: the AMDTP stream
268 * @pcm: the PCM device to be started, or %NULL to stop the current device
269 *
270 * Call this function on a running isochronous stream to enable the actual
271 * transmission of PCM data.  This function should be called from the PCM
272 * device's .trigger callback.
273 */
274static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
275					    struct snd_pcm_substream *pcm)
276{
277	WRITE_ONCE(s->pcm, pcm);
278}
279
280static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
281{
282	return sfc & 1;
283}
284
285struct seq_desc {
286	unsigned int syt_offset;
287	unsigned int data_blocks;
288};
289
290struct amdtp_domain {
291	struct list_head streams;
292
293	unsigned int events_per_period;
294	unsigned int events_per_buffer;
295
296	struct amdtp_stream *irq_target;
297
298	struct {
299		unsigned int tx_init_skip;
300		unsigned int tx_start;
301		unsigned int rx_start;
302	} processing_cycle;
303
304	struct {
305		bool enable:1;
306		bool on_the_fly:1;
307	} replay;
308};
309
310int amdtp_domain_init(struct amdtp_domain *d);
311void amdtp_domain_destroy(struct amdtp_domain *d);
312
313int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
314			    int channel, int speed);
315
316int amdtp_domain_start(struct amdtp_domain *d, unsigned int tx_init_skip_cycles, bool replay_seq,
317		       bool replay_on_the_fly);
318void amdtp_domain_stop(struct amdtp_domain *d);
319
320static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
321						unsigned int events_per_period,
322						unsigned int events_per_buffer)
323{
324	d->events_per_period = events_per_period;
325	d->events_per_buffer = events_per_buffer;
326
327	return 0;
328}
329
330unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
331					      struct amdtp_stream *s);
332int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
333
334/**
335 * amdtp_domain_wait_ready - sleep till being ready to process packets or timeout
336 * @d: the AMDTP domain
337 * @timeout_ms: msec till timeout
338 *
339 * If this function return false, the AMDTP domain should be stopped.
340 */
341static inline bool amdtp_domain_wait_ready(struct amdtp_domain *d, unsigned int timeout_ms)
342{
343	struct amdtp_stream *s;
344
345	list_for_each_entry(s, &d->streams, list) {
346		unsigned int j = msecs_to_jiffies(timeout_ms);
347
348		if (wait_event_interruptible_timeout(s->ready_wait, s->ready_processing, j) <= 0)
349			return false;
350	}
351
352	return true;
353}
354
355#endif