xref: /openbmc/linux/sound/firewire/amdtp-stream.h (revision 7587eb18)
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_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
21  * @CIP_DBC_IS_END_EVENT: Only for in-stream. The value of dbc in an in-packet
22  *	corresponds to the end of event in the packet. Out of IEC 61883.
23  * @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
24  *	The value of data_block_quadlets is used instead of reported value.
25  * @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream.  Packets with zero in dbc is
26  *	skipped for detecting discontinuity.
27  * @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
28  *	packet is wrong but the others are correct.
29  * @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
30  *	packet is larger than IEC 61883-6 defines. Current implementation
31  *	allows 5 times as large as IEC 61883-6 defines.
32  */
33 enum cip_flags {
34 	CIP_NONBLOCKING		= 0x00,
35 	CIP_BLOCKING		= 0x01,
36 	CIP_EMPTY_WITH_TAG0	= 0x02,
37 	CIP_DBC_IS_END_EVENT	= 0x04,
38 	CIP_WRONG_DBS		= 0x08,
39 	CIP_SKIP_DBC_ZERO_CHECK	= 0x10,
40 	CIP_EMPTY_HAS_WRONG_DBC	= 0x20,
41 	CIP_JUMBO_PAYLOAD	= 0x40,
42 };
43 
44 /**
45  * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
46  * @CIP_SFC_32000:   32,000 data blocks
47  * @CIP_SFC_44100:   44,100 data blocks
48  * @CIP_SFC_48000:   48,000 data blocks
49  * @CIP_SFC_88200:   88,200 data blocks
50  * @CIP_SFC_96000:   96,000 data blocks
51  * @CIP_SFC_176400: 176,400 data blocks
52  * @CIP_SFC_192000: 192,000 data blocks
53  * @CIP_SFC_COUNT: the number of supported SFCs
54  *
55  * These values are used to show nominal Sampling Frequency Code in
56  * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
57  * this code means the number of events per second. Actually the code
58  * represents the number of data blocks transferred per second in an AMDTP
59  * stream.
60  *
61  * In IEC 61883-6:2005, some extensions were added to support more types of
62  * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
63  * different depending on the types.
64  *
65  * Currently our implementation is compatible with IEC 61883-6:2002.
66  */
67 enum cip_sfc {
68 	CIP_SFC_32000  = 0,
69 	CIP_SFC_44100  = 1,
70 	CIP_SFC_48000  = 2,
71 	CIP_SFC_88200  = 3,
72 	CIP_SFC_96000  = 4,
73 	CIP_SFC_176400 = 5,
74 	CIP_SFC_192000 = 6,
75 	CIP_SFC_COUNT
76 };
77 
78 struct fw_unit;
79 struct fw_iso_context;
80 struct snd_pcm_substream;
81 struct snd_pcm_runtime;
82 
83 enum amdtp_stream_direction {
84 	AMDTP_OUT_STREAM = 0,
85 	AMDTP_IN_STREAM
86 };
87 
88 struct amdtp_stream;
89 typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
90 						struct amdtp_stream *s,
91 						__be32 *buffer,
92 						unsigned int data_blocks,
93 						unsigned int *syt);
94 struct amdtp_stream {
95 	struct fw_unit *unit;
96 	enum cip_flags flags;
97 	enum amdtp_stream_direction direction;
98 	struct mutex mutex;
99 
100 	/* For packet processing. */
101 	struct fw_iso_context *context;
102 	struct iso_packets_buffer buffer;
103 	int packet_index;
104 
105 	/* For CIP headers. */
106 	unsigned int source_node_id_field;
107 	unsigned int data_block_quadlets;
108 	unsigned int data_block_counter;
109 	unsigned int fmt;
110 	unsigned int fdf;
111 	/* quirk: fixed interval of dbc between previos/current packets. */
112 	unsigned int tx_dbc_interval;
113 	/* quirk: indicate the value of dbc field in a first packet. */
114 	unsigned int tx_first_dbc;
115 
116 	/* Internal flags. */
117 	enum cip_sfc sfc;
118 	unsigned int syt_interval;
119 	unsigned int transfer_delay;
120 	unsigned int data_block_state;
121 	unsigned int last_syt_offset;
122 	unsigned int syt_offset_state;
123 
124 	/* For a PCM substream processing. */
125 	struct snd_pcm_substream *pcm;
126 	struct tasklet_struct period_tasklet;
127 	unsigned int pcm_buffer_pointer;
128 	unsigned int pcm_period_pointer;
129 
130 	/* To wait for first packet. */
131 	bool callbacked;
132 	wait_queue_head_t callback_wait;
133 
134 	/* For backends to process data blocks. */
135 	void *protocol;
136 	amdtp_stream_process_data_blocks_t process_data_blocks;
137 };
138 
139 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
140 		      enum amdtp_stream_direction dir, enum cip_flags flags,
141 		      unsigned int fmt,
142 		      amdtp_stream_process_data_blocks_t process_data_blocks,
143 		      unsigned int protocol_size);
144 void amdtp_stream_destroy(struct amdtp_stream *s);
145 
146 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
147 				unsigned int data_block_quadlets);
148 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
149 
150 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
151 void amdtp_stream_update(struct amdtp_stream *s);
152 void amdtp_stream_stop(struct amdtp_stream *s);
153 
154 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
155 					struct snd_pcm_runtime *runtime);
156 
157 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
158 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
159 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
160 
161 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
162 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
163 
164 /**
165  * amdtp_stream_running - check stream is running or not
166  * @s: the AMDTP stream
167  *
168  * If this function returns true, the stream is running.
169  */
170 static inline bool amdtp_stream_running(struct amdtp_stream *s)
171 {
172 	return !IS_ERR(s->context);
173 }
174 
175 /**
176  * amdtp_streaming_error - check for streaming error
177  * @s: the AMDTP stream
178  *
179  * If this function returns true, the stream's packet queue has stopped due to
180  * an asynchronous error.
181  */
182 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
183 {
184 	return s->packet_index < 0;
185 }
186 
187 /**
188  * amdtp_stream_pcm_running - check PCM substream is running or not
189  * @s: the AMDTP stream
190  *
191  * If this function returns true, PCM substream in the AMDTP stream is running.
192  */
193 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
194 {
195 	return !!s->pcm;
196 }
197 
198 /**
199  * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
200  * @s: the AMDTP stream
201  * @pcm: the PCM device to be started, or %NULL to stop the current device
202  *
203  * Call this function on a running isochronous stream to enable the actual
204  * transmission of PCM data.  This function should be called from the PCM
205  * device's .trigger callback.
206  */
207 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
208 					    struct snd_pcm_substream *pcm)
209 {
210 	ACCESS_ONCE(s->pcm) = pcm;
211 }
212 
213 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
214 {
215 	return sfc & 1;
216 }
217 
218 /**
219  * amdtp_stream_wait_callback - sleep till callbacked or timeout
220  * @s: the AMDTP stream
221  * @timeout: msec till timeout
222  *
223  * If this function return false, the AMDTP stream should be stopped.
224  */
225 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
226 					      unsigned int timeout)
227 {
228 	return wait_event_timeout(s->callback_wait,
229 				  s->callbacked == true,
230 				  msecs_to_jiffies(timeout)) > 0;
231 }
232 
233 #endif
234