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 */
37 enum cip_flags {
38 CIP_NONBLOCKING = 0x00,
39 CIP_BLOCKING = 0x01,
40 CIP_EMPTY_WITH_TAG0 = 0x02,
41 CIP_DBC_IS_END_EVENT = 0x04,
42 CIP_WRONG_DBS = 0x08,
43 CIP_SKIP_DBC_ZERO_CHECK = 0x10,
44 CIP_EMPTY_HAS_WRONG_DBC = 0x20,
45 CIP_JUMBO_PAYLOAD = 0x40,
46 CIP_HEADER_WITHOUT_EOH = 0x80,
47 CIP_NO_HEADER = 0x100,
48 };
49
50 /**
51 * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
52 * @CIP_SFC_32000: 32,000 data blocks
53 * @CIP_SFC_44100: 44,100 data blocks
54 * @CIP_SFC_48000: 48,000 data blocks
55 * @CIP_SFC_88200: 88,200 data blocks
56 * @CIP_SFC_96000: 96,000 data blocks
57 * @CIP_SFC_176400: 176,400 data blocks
58 * @CIP_SFC_192000: 192,000 data blocks
59 * @CIP_SFC_COUNT: the number of supported SFCs
60 *
61 * These values are used to show nominal Sampling Frequency Code in
62 * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
63 * this code means the number of events per second. Actually the code
64 * represents the number of data blocks transferred per second in an AMDTP
65 * stream.
66 *
67 * In IEC 61883-6:2005, some extensions were added to support more types of
68 * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
69 * different depending on the types.
70 *
71 * Currently our implementation is compatible with IEC 61883-6:2002.
72 */
73 enum cip_sfc {
74 CIP_SFC_32000 = 0,
75 CIP_SFC_44100 = 1,
76 CIP_SFC_48000 = 2,
77 CIP_SFC_88200 = 3,
78 CIP_SFC_96000 = 4,
79 CIP_SFC_176400 = 5,
80 CIP_SFC_192000 = 6,
81 CIP_SFC_COUNT
82 };
83
84 struct fw_unit;
85 struct fw_iso_context;
86 struct snd_pcm_substream;
87 struct snd_pcm_runtime;
88
89 enum amdtp_stream_direction {
90 AMDTP_OUT_STREAM = 0,
91 AMDTP_IN_STREAM
92 };
93
94 struct amdtp_stream;
95 typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
96 struct amdtp_stream *s,
97 __be32 *buffer,
98 unsigned int data_blocks,
99 unsigned int *syt);
100 struct amdtp_stream {
101 struct fw_unit *unit;
102 enum cip_flags flags;
103 enum amdtp_stream_direction direction;
104 struct mutex mutex;
105
106 /* For packet processing. */
107 struct fw_iso_context *context;
108 struct iso_packets_buffer buffer;
109 int packet_index;
110 int tag;
111 int (*handle_packet)(struct amdtp_stream *s,
112 unsigned int payload_quadlets, unsigned int cycle,
113 unsigned int index);
114 unsigned int max_payload_length;
115
116 /* For CIP headers. */
117 unsigned int source_node_id_field;
118 unsigned int data_block_quadlets;
119 unsigned int data_block_counter;
120 unsigned int sph;
121 unsigned int fmt;
122 unsigned int fdf;
123 /* quirk: fixed interval of dbc between previos/current packets. */
124 unsigned int tx_dbc_interval;
125 /* quirk: indicate the value of dbc field in a first packet. */
126 unsigned int tx_first_dbc;
127
128 /* Internal flags. */
129 enum cip_sfc sfc;
130 unsigned int syt_interval;
131 unsigned int transfer_delay;
132 unsigned int data_block_state;
133 unsigned int last_syt_offset;
134 unsigned int syt_offset_state;
135
136 /* For a PCM substream processing. */
137 struct snd_pcm_substream *pcm;
138 struct tasklet_struct period_tasklet;
139 snd_pcm_uframes_t pcm_buffer_pointer;
140 unsigned int pcm_period_pointer;
141
142 /* To wait for first packet. */
143 bool callbacked;
144 wait_queue_head_t callback_wait;
145 u32 start_cycle;
146
147 /* For backends to process data blocks. */
148 void *protocol;
149 amdtp_stream_process_data_blocks_t process_data_blocks;
150 };
151
152 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
153 enum amdtp_stream_direction dir, enum cip_flags flags,
154 unsigned int fmt,
155 amdtp_stream_process_data_blocks_t process_data_blocks,
156 unsigned int protocol_size);
157 void amdtp_stream_destroy(struct amdtp_stream *s);
158
159 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
160 unsigned int data_block_quadlets);
161 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
162
163 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
164 void amdtp_stream_update(struct amdtp_stream *s);
165 void amdtp_stream_stop(struct amdtp_stream *s);
166
167 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
168 struct snd_pcm_runtime *runtime);
169
170 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
171 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
172 int amdtp_stream_pcm_ack(struct amdtp_stream *s);
173 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
174
175 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
176 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
177
178 /**
179 * amdtp_stream_running - check stream is running or not
180 * @s: the AMDTP stream
181 *
182 * If this function returns true, the stream is running.
183 */
amdtp_stream_running(struct amdtp_stream * s)184 static inline bool amdtp_stream_running(struct amdtp_stream *s)
185 {
186 return !IS_ERR(s->context);
187 }
188
189 /**
190 * amdtp_streaming_error - check for streaming error
191 * @s: the AMDTP stream
192 *
193 * If this function returns true, the stream's packet queue has stopped due to
194 * an asynchronous error.
195 */
amdtp_streaming_error(struct amdtp_stream * s)196 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
197 {
198 return s->packet_index < 0;
199 }
200
201 /**
202 * amdtp_stream_pcm_running - check PCM substream is running or not
203 * @s: the AMDTP stream
204 *
205 * If this function returns true, PCM substream in the AMDTP stream is running.
206 */
amdtp_stream_pcm_running(struct amdtp_stream * s)207 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
208 {
209 return !!s->pcm;
210 }
211
212 /**
213 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
214 * @s: the AMDTP stream
215 * @pcm: the PCM device to be started, or %NULL to stop the current device
216 *
217 * Call this function on a running isochronous stream to enable the actual
218 * transmission of PCM data. This function should be called from the PCM
219 * device's .trigger callback.
220 */
amdtp_stream_pcm_trigger(struct amdtp_stream * s,struct snd_pcm_substream * pcm)221 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
222 struct snd_pcm_substream *pcm)
223 {
224 WRITE_ONCE(s->pcm, pcm);
225 }
226
cip_sfc_is_base_44100(enum cip_sfc sfc)227 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
228 {
229 return sfc & 1;
230 }
231
232 /**
233 * amdtp_stream_wait_callback - sleep till callbacked or timeout
234 * @s: the AMDTP stream
235 * @timeout: msec till timeout
236 *
237 * If this function return false, the AMDTP stream should be stopped.
238 */
amdtp_stream_wait_callback(struct amdtp_stream * s,unsigned int timeout)239 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
240 unsigned int timeout)
241 {
242 return wait_event_timeout(s->callback_wait,
243 s->callbacked == true,
244 msecs_to_jiffies(timeout)) > 0;
245 }
246
247 #endif
248
