xref: /openbmc/linux/sound/firewire/amdtp-stream.h (revision a06c488d)
1 #ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
2 #define SOUND_FIREWIRE_AMDTP_H_INCLUDED
3 
4 #include <linux/err.h>
5 #include <linux/interrupt.h>
6 #include <linux/mutex.h>
7 #include <linux/sched.h>
8 #include <sound/asound.h>
9 #include "packets-buffer.h"
10 
11 /**
12  * enum cip_flags - describes details of the streaming protocol
13  * @CIP_NONBLOCKING: In non-blocking mode, each packet contains
14  *	sample_rate/8000 samples, with rounding up or down to adjust
15  *	for clock skew and left-over fractional samples.  This should
16  *	be used if supported by the device.
17  * @CIP_BLOCKING: In blocking mode, each packet contains either zero or
18  *	SYT_INTERVAL samples, with these two types alternating so that
19  *	the overall sample rate comes out right.
20  * @CIP_SYNC_TO_DEVICE: In sync to device mode, time stamp in out packets is
21  *	generated by in packets. Defaultly this driver generates timestamp.
22  * @CIP_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
23  * @CIP_DBC_IS_END_EVENT: Only for in-stream. The value of dbc in an in-packet
24  *	corresponds to the end of event in the packet. Out of IEC 61883.
25  * @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
26  *	The value of data_block_quadlets is used instead of reported value.
27  * @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream.  Packets with zero in dbc is
28  *	skipped for detecting discontinuity.
29  * @CIP_SKIP_INIT_DBC_CHECK: Only for in-stream. The value of dbc in first
30  *	packet is not continuous from an initial value.
31  * @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
32  *	packet is wrong but the others are correct.
33  * @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
34  *	packet is larger than IEC 61883-6 defines. Current implementation
35  *	allows 5 times as large as IEC 61883-6 defines.
36  */
37 enum cip_flags {
38 	CIP_NONBLOCKING		= 0x00,
39 	CIP_BLOCKING		= 0x01,
40 	CIP_SYNC_TO_DEVICE	= 0x02,
41 	CIP_EMPTY_WITH_TAG0	= 0x04,
42 	CIP_DBC_IS_END_EVENT	= 0x08,
43 	CIP_WRONG_DBS		= 0x10,
44 	CIP_SKIP_DBC_ZERO_CHECK	= 0x20,
45 	CIP_SKIP_INIT_DBC_CHECK	= 0x40,
46 	CIP_EMPTY_HAS_WRONG_DBC	= 0x80,
47 	CIP_JUMBO_PAYLOAD	= 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 
111 	/* For CIP headers. */
112 	unsigned int source_node_id_field;
113 	unsigned int data_block_quadlets;
114 	unsigned int data_block_counter;
115 	unsigned int fmt;
116 	unsigned int fdf;
117 	/* quirk: fixed interval of dbc between previos/current packets. */
118 	unsigned int tx_dbc_interval;
119 	/* quirk: indicate the value of dbc field in a first packet. */
120 	unsigned int tx_first_dbc;
121 
122 	/* Internal flags. */
123 	enum cip_sfc sfc;
124 	unsigned int syt_interval;
125 	unsigned int transfer_delay;
126 	unsigned int data_block_state;
127 	unsigned int last_syt_offset;
128 	unsigned int syt_offset_state;
129 
130 	/* For a PCM substream processing. */
131 	struct snd_pcm_substream *pcm;
132 	struct tasklet_struct period_tasklet;
133 	unsigned int pcm_buffer_pointer;
134 	unsigned int pcm_period_pointer;
135 	bool pointer_flush;
136 
137 	/* To wait for first packet. */
138 	bool callbacked;
139 	wait_queue_head_t callback_wait;
140 	struct amdtp_stream *sync_slave;
141 
142 	/* For backends to process data blocks. */
143 	void *protocol;
144 	amdtp_stream_process_data_blocks_t process_data_blocks;
145 };
146 
147 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
148 		      enum amdtp_stream_direction dir, enum cip_flags flags,
149 		      unsigned int fmt,
150 		      amdtp_stream_process_data_blocks_t process_data_blocks,
151 		      unsigned int protocol_size);
152 void amdtp_stream_destroy(struct amdtp_stream *s);
153 
154 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
155 				unsigned int data_block_quadlets);
156 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
157 
158 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
159 void amdtp_stream_update(struct amdtp_stream *s);
160 void amdtp_stream_stop(struct amdtp_stream *s);
161 
162 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
163 					struct snd_pcm_runtime *runtime);
164 
165 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
166 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
167 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
168 
169 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
170 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
171 
172 /**
173  * amdtp_stream_running - check stream is running or not
174  * @s: the AMDTP stream
175  *
176  * If this function returns true, the stream is running.
177  */
178 static inline bool amdtp_stream_running(struct amdtp_stream *s)
179 {
180 	return !IS_ERR(s->context);
181 }
182 
183 /**
184  * amdtp_streaming_error - check for streaming error
185  * @s: the AMDTP stream
186  *
187  * If this function returns true, the stream's packet queue has stopped due to
188  * an asynchronous error.
189  */
190 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
191 {
192 	return s->packet_index < 0;
193 }
194 
195 /**
196  * amdtp_stream_pcm_running - check PCM substream is running or not
197  * @s: the AMDTP stream
198  *
199  * If this function returns true, PCM substream in the AMDTP stream is running.
200  */
201 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
202 {
203 	return !!s->pcm;
204 }
205 
206 /**
207  * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
208  * @s: the AMDTP stream
209  * @pcm: the PCM device to be started, or %NULL to stop the current device
210  *
211  * Call this function on a running isochronous stream to enable the actual
212  * transmission of PCM data.  This function should be called from the PCM
213  * device's .trigger callback.
214  */
215 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
216 					    struct snd_pcm_substream *pcm)
217 {
218 	ACCESS_ONCE(s->pcm) = pcm;
219 }
220 
221 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
222 {
223 	return sfc & 1;
224 }
225 
226 static inline void amdtp_stream_set_sync(enum cip_flags sync_mode,
227 					 struct amdtp_stream *master,
228 					 struct amdtp_stream *slave)
229 {
230 	if (sync_mode == CIP_SYNC_TO_DEVICE) {
231 		master->flags |= CIP_SYNC_TO_DEVICE;
232 		slave->flags |= CIP_SYNC_TO_DEVICE;
233 		master->sync_slave = slave;
234 	} else {
235 		master->flags &= ~CIP_SYNC_TO_DEVICE;
236 		slave->flags &= ~CIP_SYNC_TO_DEVICE;
237 		master->sync_slave = NULL;
238 	}
239 
240 	slave->sync_slave = NULL;
241 }
242 
243 /**
244  * amdtp_stream_wait_callback - sleep till callbacked or timeout
245  * @s: the AMDTP stream
246  * @timeout: msec till timeout
247  *
248  * If this function return false, the AMDTP stream should be stopped.
249  */
250 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
251 					      unsigned int timeout)
252 {
253 	return wait_event_timeout(s->callback_wait,
254 				  s->callbacked == true,
255 				  msecs_to_jiffies(timeout)) > 0;
256 }
257 
258 #endif
259