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 */
39enum cip_flags {
40	CIP_NONBLOCKING		= 0x00,
41	CIP_BLOCKING		= 0x01,
42	CIP_EMPTY_WITH_TAG0	= 0x02,
43	CIP_DBC_IS_END_EVENT	= 0x04,
44	CIP_WRONG_DBS		= 0x08,
45	CIP_SKIP_DBC_ZERO_CHECK	= 0x10,
46	CIP_EMPTY_HAS_WRONG_DBC	= 0x20,
47	CIP_JUMBO_PAYLOAD	= 0x40,
48	CIP_HEADER_WITHOUT_EOH	= 0x80,
49	CIP_NO_HEADER		= 0x100,
50	CIP_UNALIGHED_DBC	= 0x200,
51};
52
53/**
54 * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
55 * @CIP_SFC_32000:   32,000 data blocks
56 * @CIP_SFC_44100:   44,100 data blocks
57 * @CIP_SFC_48000:   48,000 data blocks
58 * @CIP_SFC_88200:   88,200 data blocks
59 * @CIP_SFC_96000:   96,000 data blocks
60 * @CIP_SFC_176400: 176,400 data blocks
61 * @CIP_SFC_192000: 192,000 data blocks
62 * @CIP_SFC_COUNT: the number of supported SFCs
63 *
64 * These values are used to show nominal Sampling Frequency Code in
65 * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
66 * this code means the number of events per second. Actually the code
67 * represents the number of data blocks transferred per second in an AMDTP
68 * stream.
69 *
70 * In IEC 61883-6:2005, some extensions were added to support more types of
71 * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
72 * different depending on the types.
73 *
74 * Currently our implementation is compatible with IEC 61883-6:2002.
75 */
76enum cip_sfc {
77	CIP_SFC_32000  = 0,
78	CIP_SFC_44100  = 1,
79	CIP_SFC_48000  = 2,
80	CIP_SFC_88200  = 3,
81	CIP_SFC_96000  = 4,
82	CIP_SFC_176400 = 5,
83	CIP_SFC_192000 = 6,
84	CIP_SFC_COUNT
85};
86
87struct fw_unit;
88struct fw_iso_context;
89struct snd_pcm_substream;
90struct snd_pcm_runtime;
91
92enum amdtp_stream_direction {
93	AMDTP_OUT_STREAM = 0,
94	AMDTP_IN_STREAM
95};
96
97struct pkt_desc {
98	u32 cycle;
99	u32 syt;
100	unsigned int data_blocks;
101	unsigned int data_block_counter;
102	__be32 *ctx_payload;
103};
104
105struct amdtp_stream;
106typedef unsigned int (*amdtp_stream_process_ctx_payloads_t)(
107						struct amdtp_stream *s,
108						const struct pkt_desc *desc,
109						unsigned int packets,
110						struct snd_pcm_substream *pcm);
111
112struct amdtp_domain;
113struct amdtp_stream {
114	struct fw_unit *unit;
115	enum cip_flags flags;
116	enum amdtp_stream_direction direction;
117	struct mutex mutex;
118
119	/* For packet processing. */
120	struct fw_iso_context *context;
121	struct iso_packets_buffer buffer;
122	unsigned int queue_size;
123	int packet_index;
124	struct pkt_desc *pkt_descs;
125	int tag;
126	union {
127		struct {
128			unsigned int ctx_header_size;
129
130			// limit for payload of iso packet.
131			unsigned int max_ctx_payload_length;
132
133			// For quirks of CIP headers.
134			// Fixed interval of dbc between previos/current
135			// packets.
136			unsigned int dbc_interval;
137		} tx;
138		struct {
139			// To calculate CIP data blocks and tstamp.
140			unsigned int transfer_delay;
141			unsigned int seq_index;
142
143			// To generate CIP header.
144			unsigned int fdf;
145			int syt_override;
146
147			// To generate constant hardware IRQ.
148			unsigned int event_count;
149			unsigned int events_per_period;
150		} rx;
151	} ctx_data;
152
153	/* For CIP headers. */
154	unsigned int source_node_id_field;
155	unsigned int data_block_quadlets;
156	unsigned int data_block_counter;
157	unsigned int sph;
158	unsigned int fmt;
159
160	/* Internal flags. */
161	enum cip_sfc sfc;
162	unsigned int syt_interval;
163
164	/* For a PCM substream processing. */
165	struct snd_pcm_substream *pcm;
166	struct work_struct period_work;
167	snd_pcm_uframes_t pcm_buffer_pointer;
168	unsigned int pcm_period_pointer;
169
170	/* To wait for first packet. */
171	bool callbacked;
172	wait_queue_head_t callback_wait;
173	u32 start_cycle;
174
175	/* For backends to process data blocks. */
176	void *protocol;
177	amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
178
179	// For domain.
180	int channel;
181	int speed;
182	struct list_head list;
183	struct amdtp_domain *domain;
184};
185
186int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
187		      enum amdtp_stream_direction dir, enum cip_flags flags,
188		      unsigned int fmt,
189		      amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
190		      unsigned int protocol_size);
191void amdtp_stream_destroy(struct amdtp_stream *s);
192
193int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
194				unsigned int data_block_quadlets);
195unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
196
197void amdtp_stream_update(struct amdtp_stream *s);
198
199int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
200					struct snd_pcm_runtime *runtime);
201
202void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
203void amdtp_stream_pcm_abort(struct amdtp_stream *s);
204
205extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
206extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
207
208/**
209 * amdtp_stream_running - check stream is running or not
210 * @s: the AMDTP stream
211 *
212 * If this function returns true, the stream is running.
213 */
214static inline bool amdtp_stream_running(struct amdtp_stream *s)
215{
216	return !IS_ERR(s->context);
217}
218
219/**
220 * amdtp_streaming_error - check for streaming error
221 * @s: the AMDTP stream
222 *
223 * If this function returns true, the stream's packet queue has stopped due to
224 * an asynchronous error.
225 */
226static inline bool amdtp_streaming_error(struct amdtp_stream *s)
227{
228	return s->packet_index < 0;
229}
230
231/**
232 * amdtp_stream_pcm_running - check PCM substream is running or not
233 * @s: the AMDTP stream
234 *
235 * If this function returns true, PCM substream in the AMDTP stream is running.
236 */
237static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
238{
239	return !!s->pcm;
240}
241
242/**
243 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
244 * @s: the AMDTP stream
245 * @pcm: the PCM device to be started, or %NULL to stop the current device
246 *
247 * Call this function on a running isochronous stream to enable the actual
248 * transmission of PCM data.  This function should be called from the PCM
249 * device's .trigger callback.
250 */
251static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
252					    struct snd_pcm_substream *pcm)
253{
254	WRITE_ONCE(s->pcm, pcm);
255}
256
257static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
258{
259	return sfc & 1;
260}
261
262/**
263 * amdtp_stream_wait_callback - sleep till callbacked or timeout
264 * @s: the AMDTP stream
265 * @timeout: msec till timeout
266 *
267 * If this function return false, the AMDTP stream should be stopped.
268 */
269static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
270					      unsigned int timeout)
271{
272	return wait_event_timeout(s->callback_wait,
273				  s->callbacked == true,
274				  msecs_to_jiffies(timeout)) > 0;
275}
276
277struct seq_desc {
278	unsigned int syt_offset;
279	unsigned int data_blocks;
280};
281
282struct amdtp_domain {
283	struct list_head streams;
284
285	unsigned int events_per_period;
286	unsigned int events_per_buffer;
287
288	struct amdtp_stream *irq_target;
289
290	struct seq_desc *seq_descs;
291	unsigned int seq_size;
292	unsigned int seq_tail;
293
294	unsigned int data_block_state;
295	unsigned int syt_offset_state;
296	unsigned int last_syt_offset;
297};
298
299int amdtp_domain_init(struct amdtp_domain *d);
300void amdtp_domain_destroy(struct amdtp_domain *d);
301
302int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
303			    int channel, int speed);
304
305int amdtp_domain_start(struct amdtp_domain *d, unsigned int ir_delay_cycle);
306void amdtp_domain_stop(struct amdtp_domain *d);
307
308static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
309						unsigned int events_per_period,
310						unsigned int events_per_buffer)
311{
312	d->events_per_period = events_per_period;
313	d->events_per_buffer = events_per_buffer;
314
315	return 0;
316}
317
318unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
319					      struct amdtp_stream *s);
320int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
321
322#endif
323