1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
3 #define SOUND_FIREWIRE_AMDTP_H_INCLUDED
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"
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
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.
40 CIP_NONBLOCKING = 0x00,
42 CIP_EMPTY_WITH_TAG0 = 0x02,
43 CIP_DBC_IS_END_EVENT = 0x04,
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,
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
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
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.
74 * Currently our implementation is compatible with IEC 61883-6:2002.
88 struct fw_iso_context;
89 struct snd_pcm_substream;
90 struct snd_pcm_runtime;
92 enum amdtp_stream_direction {
100 unsigned int data_blocks;
101 unsigned int data_block_counter;
106 typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
107 struct amdtp_stream *s,
108 const struct pkt_desc *desc,
109 struct snd_pcm_substream *pcm);
110 struct amdtp_stream {
111 struct fw_unit *unit;
112 enum cip_flags flags;
113 enum amdtp_stream_direction direction;
116 /* For packet processing. */
117 struct fw_iso_context *context;
118 struct iso_packets_buffer buffer;
120 struct pkt_desc *pkt_descs;
124 unsigned int ctx_header_size;
126 // limit for payload of iso packet.
127 unsigned int max_ctx_payload_length;
129 // For quirks of CIP headers.
130 // Fixed interval of dbc between previos/current
132 unsigned int dbc_interval;
135 // To calculate CIP data blocks and tstamp.
136 unsigned int transfer_delay;
137 unsigned int data_block_state;
138 unsigned int last_syt_offset;
139 unsigned int syt_offset_state;
141 // To generate CIP header.
147 /* For CIP headers. */
148 unsigned int source_node_id_field;
149 unsigned int data_block_quadlets;
150 unsigned int data_block_counter;
154 /* Internal flags. */
156 unsigned int syt_interval;
158 /* For a PCM substream processing. */
159 struct snd_pcm_substream *pcm;
160 struct tasklet_struct period_tasklet;
161 snd_pcm_uframes_t pcm_buffer_pointer;
162 unsigned int pcm_period_pointer;
164 /* To wait for first packet. */
166 wait_queue_head_t callback_wait;
169 /* For backends to process data blocks. */
171 amdtp_stream_process_data_blocks_t process_data_blocks;
174 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
175 enum amdtp_stream_direction dir, enum cip_flags flags,
177 amdtp_stream_process_data_blocks_t process_data_blocks,
178 unsigned int protocol_size);
179 void amdtp_stream_destroy(struct amdtp_stream *s);
181 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
182 unsigned int data_block_quadlets);
183 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
185 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
186 void amdtp_stream_update(struct amdtp_stream *s);
187 void amdtp_stream_stop(struct amdtp_stream *s);
189 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
190 struct snd_pcm_runtime *runtime);
192 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
193 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
194 int amdtp_stream_pcm_ack(struct amdtp_stream *s);
195 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
197 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
198 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
201 * amdtp_stream_running - check stream is running or not
202 * @s: the AMDTP stream
204 * If this function returns true, the stream is running.
206 static inline bool amdtp_stream_running(struct amdtp_stream *s)
208 return !IS_ERR(s->context);
212 * amdtp_streaming_error - check for streaming error
213 * @s: the AMDTP stream
215 * If this function returns true, the stream's packet queue has stopped due to
216 * an asynchronous error.
218 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
220 return s->packet_index < 0;
224 * amdtp_stream_pcm_running - check PCM substream is running or not
225 * @s: the AMDTP stream
227 * If this function returns true, PCM substream in the AMDTP stream is running.
229 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
235 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
236 * @s: the AMDTP stream
237 * @pcm: the PCM device to be started, or %NULL to stop the current device
239 * Call this function on a running isochronous stream to enable the actual
240 * transmission of PCM data. This function should be called from the PCM
241 * device's .trigger callback.
243 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
244 struct snd_pcm_substream *pcm)
246 WRITE_ONCE(s->pcm, pcm);
249 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
255 * amdtp_stream_wait_callback - sleep till callbacked or timeout
256 * @s: the AMDTP stream
257 * @timeout: msec till timeout
259 * If this function return false, the AMDTP stream should be stopped.
261 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
262 unsigned int timeout)
264 return wait_event_timeout(s->callback_wait,
265 s->callbacked == true,
266 msecs_to_jiffies(timeout)) > 0;