1 /* SPDX-License-Identifier: GPL-2.0-only */ <<
2 /* 1 /*
3 * Line 6 Linux USB driver 2 * Line 6 Linux USB driver
4 * 3 *
5 * Copyright (C) 2004-2010 Markus Grabner (lin !! 4 * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
>> 5 *
>> 6 * This program is free software; you can redistribute it and/or
>> 7 * modify it under the terms of the GNU General Public License as
>> 8 * published by the Free Software Foundation, version 2.
>> 9 *
6 */ 10 */
7 11
8 /* 12 /*
9 PCM interface to POD series devices. 13 PCM interface to POD series devices.
10 */ 14 */
11 15
12 #ifndef PCM_H 16 #ifndef PCM_H
13 #define PCM_H 17 #define PCM_H
14 18
15 #include <sound/pcm.h> 19 #include <sound/pcm.h>
16 20
17 #include "driver.h" 21 #include "driver.h"
18 22
19 /* 23 /*
20 number of USB frames per URB 24 number of USB frames per URB
21 The Line 6 Windows driver always trans 25 The Line 6 Windows driver always transmits two frames per packet, but
22 the Linux driver performs significantl 26 the Linux driver performs significantly better (i.e., lower latency)
23 with only one frame per packet. 27 with only one frame per packet.
24 */ 28 */
25 #define LINE6_ISO_PACKETS 1 29 #define LINE6_ISO_PACKETS 1
26 30
27 /* in a "full speed" device (such as the PODxt 31 /* in a "full speed" device (such as the PODxt Pro) this means 1ms,
28 * for "high speed" it's 1/8ms 32 * for "high speed" it's 1/8ms
29 */ 33 */
30 #define LINE6_ISO_INTERVAL 1 34 #define LINE6_ISO_INTERVAL 1
31 35
32 #define LINE6_IMPULSE_DEFAULT_PERIOD 100 36 #define LINE6_IMPULSE_DEFAULT_PERIOD 100
33 37
34 /* 38 /*
35 Get substream from Line 6 PCM data str 39 Get substream from Line 6 PCM data structure
36 */ 40 */
37 #define get_substream(line6pcm, stream) \ 41 #define get_substream(line6pcm, stream) \
38 (line6pcm->pcm->streams[stream 42 (line6pcm->pcm->streams[stream].substream)
39 43
40 /* 44 /*
41 PCM mode bits. 45 PCM mode bits.
42 46
43 There are several features of the Line 47 There are several features of the Line 6 USB driver which require PCM
44 data to be exchanged with the device: 48 data to be exchanged with the device:
45 *) PCM playback and capture via ALSA 49 *) PCM playback and capture via ALSA
46 *) software monitoring (for devices wi 50 *) software monitoring (for devices without hardware monitoring)
47 *) optional impulse response measureme 51 *) optional impulse response measurement
48 However, from the device's point of vi 52 However, from the device's point of view, there is just a single
49 capture and playback stream, which mus 53 capture and playback stream, which must be shared between these
50 subsystems. It is therefore necessary 54 subsystems. It is therefore necessary to maintain the state of the
51 subsystems with respect to PCM usage. 55 subsystems with respect to PCM usage.
52 56
53 We define two bit flags, "opened" and 57 We define two bit flags, "opened" and "running", for each playback
54 or capture stream. Both can contain t 58 or capture stream. Both can contain the bit flag corresponding to
55 LINE6_STREAM_* type, 59 LINE6_STREAM_* type,
56 LINE6_STREAM_PCM = ALSA PCM playback 60 LINE6_STREAM_PCM = ALSA PCM playback or capture
57 LINE6_STREAM_MONITOR = software moni 61 LINE6_STREAM_MONITOR = software monitoring
58 IMPULSE = optional impulse response 62 IMPULSE = optional impulse response measurement
59 The opened flag indicates whether the 63 The opened flag indicates whether the buffer is allocated while
60 the running flag indicates whether the 64 the running flag indicates whether the stream is running.
61 65
62 For monitor or impulse operations, the 66 For monitor or impulse operations, the driver needs to call
63 line6_pcm_acquire() or line6_pcm_relea 67 line6_pcm_acquire() or line6_pcm_release() with the appropriate
64 LINE6_STREAM_* flag. 68 LINE6_STREAM_* flag.
65 */ 69 */
66 70
67 /* stream types */ 71 /* stream types */
68 enum { 72 enum {
69 LINE6_STREAM_PCM, 73 LINE6_STREAM_PCM,
70 LINE6_STREAM_MONITOR, 74 LINE6_STREAM_MONITOR,
71 LINE6_STREAM_IMPULSE, 75 LINE6_STREAM_IMPULSE,
72 LINE6_STREAM_CAPTURE_HELPER, 76 LINE6_STREAM_CAPTURE_HELPER,
73 }; 77 };
74 78
75 /* misc bit flags for PCM operation */ 79 /* misc bit flags for PCM operation */
76 enum { 80 enum {
77 LINE6_FLAG_PAUSE_PLAYBACK, 81 LINE6_FLAG_PAUSE_PLAYBACK,
78 LINE6_FLAG_PREPARED, 82 LINE6_FLAG_PREPARED,
79 }; 83 };
80 84
81 struct line6_pcm_properties { 85 struct line6_pcm_properties {
82 struct snd_pcm_hardware playback_hw, c 86 struct snd_pcm_hardware playback_hw, capture_hw;
83 struct snd_pcm_hw_constraint_ratdens r 87 struct snd_pcm_hw_constraint_ratdens rates;
84 int bytes_per_channel; 88 int bytes_per_channel;
85 }; 89 };
86 90
87 struct line6_pcm_stream { 91 struct line6_pcm_stream {
88 /* allocated URBs */ 92 /* allocated URBs */
89 struct urb **urbs; 93 struct urb **urbs;
90 94
91 /* Temporary buffer; 95 /* Temporary buffer;
92 * Since the packet size is not known 96 * Since the packet size is not known in advance, this buffer is
93 * large enough to store maximum size 97 * large enough to store maximum size packets.
94 */ 98 */
95 unsigned char *buffer; 99 unsigned char *buffer;
96 100
97 /* Free frame position in the buffer. 101 /* Free frame position in the buffer. */
98 snd_pcm_uframes_t pos; 102 snd_pcm_uframes_t pos;
99 103
100 /* Count processed bytes; 104 /* Count processed bytes;
101 * This is modulo period size (to dete 105 * This is modulo period size (to determine when a period is finished).
102 */ 106 */
103 unsigned bytes; 107 unsigned bytes;
104 108
105 /* Counter to create desired sample ra 109 /* Counter to create desired sample rate */
106 unsigned count; 110 unsigned count;
107 111
108 /* period size in bytes */ 112 /* period size in bytes */
109 unsigned period; 113 unsigned period;
110 114
111 /* Processed frame position in the buf 115 /* Processed frame position in the buffer;
112 * The contents of the ring buffer hav 116 * The contents of the ring buffer have been consumed by the USB
113 * subsystem (i.e., sent to the USB de 117 * subsystem (i.e., sent to the USB device) up to this position.
114 */ 118 */
115 snd_pcm_uframes_t pos_done; 119 snd_pcm_uframes_t pos_done;
116 120
117 /* Bit mask of active URBs */ 121 /* Bit mask of active URBs */
118 unsigned long active_urbs; 122 unsigned long active_urbs;
119 123
120 /* Bit mask of URBs currently being un 124 /* Bit mask of URBs currently being unlinked */
121 unsigned long unlink_urbs; 125 unsigned long unlink_urbs;
122 126
123 /* Spin lock to protect updates of the 127 /* Spin lock to protect updates of the buffer positions (not contents)
124 */ 128 */
125 spinlock_t lock; 129 spinlock_t lock;
126 130
127 /* Bit flags for operational stream ty 131 /* Bit flags for operational stream types */
128 unsigned long opened; 132 unsigned long opened;
129 133
130 /* Bit flags for running stream types 134 /* Bit flags for running stream types */
131 unsigned long running; 135 unsigned long running;
132 136
133 int last_frame; 137 int last_frame;
134 }; 138 };
135 139
136 struct snd_line6_pcm { 140 struct snd_line6_pcm {
137 /* Pointer back to the Line 6 driver d 141 /* Pointer back to the Line 6 driver data structure */
138 struct usb_line6 *line6; 142 struct usb_line6 *line6;
139 143
140 /* Properties. */ 144 /* Properties. */
141 struct line6_pcm_properties *propertie 145 struct line6_pcm_properties *properties;
142 146
143 /* ALSA pcm stream */ 147 /* ALSA pcm stream */
144 struct snd_pcm *pcm; 148 struct snd_pcm *pcm;
145 149
146 /* protection to state changes of in/o 150 /* protection to state changes of in/out streams */
147 struct mutex state_mutex; 151 struct mutex state_mutex;
148 152
149 /* Capture and playback streams */ 153 /* Capture and playback streams */
150 struct line6_pcm_stream in; 154 struct line6_pcm_stream in;
151 struct line6_pcm_stream out; 155 struct line6_pcm_stream out;
152 156
153 /* Previously captured frame (for soft 157 /* Previously captured frame (for software monitoring) */
154 unsigned char *prev_fbuf; 158 unsigned char *prev_fbuf;
155 159
156 /* Size of previously captured frame ( 160 /* Size of previously captured frame (for software monitoring/sync) */
157 int prev_fsize; 161 int prev_fsize;
158 162
159 /* Maximum size of USB packet */ 163 /* Maximum size of USB packet */
160 int max_packet_size_in; 164 int max_packet_size_in;
161 int max_packet_size_out; 165 int max_packet_size_out;
162 166
163 /* PCM playback volume (left and right 167 /* PCM playback volume (left and right) */
164 int volume_playback[2]; 168 int volume_playback[2];
165 169
166 /* PCM monitor volume */ 170 /* PCM monitor volume */
167 int volume_monitor; 171 int volume_monitor;
168 172
169 /* Volume of impulse response test sig 173 /* Volume of impulse response test signal (if zero, test is disabled) */
170 int impulse_volume; 174 int impulse_volume;
171 175
172 /* Period of impulse response test sig 176 /* Period of impulse response test signal */
173 int impulse_period; 177 int impulse_period;
174 178
175 /* Counter for impulse response test s 179 /* Counter for impulse response test signal */
176 int impulse_count; 180 int impulse_count;
177 181
178 /* Several status bits (see LINE6_FLAG 182 /* Several status bits (see LINE6_FLAG_*) */
179 unsigned long flags; 183 unsigned long flags;
180 }; 184 };
181 185
182 extern int line6_init_pcm(struct usb_line6 *li 186 extern int line6_init_pcm(struct usb_line6 *line6,
183 struct line6_pcm_pro 187 struct line6_pcm_properties *properties);
184 extern int snd_line6_trigger(struct snd_pcm_su 188 extern int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd);
185 extern int snd_line6_prepare(struct snd_pcm_su 189 extern int snd_line6_prepare(struct snd_pcm_substream *substream);
186 extern int snd_line6_hw_params(struct snd_pcm_ 190 extern int snd_line6_hw_params(struct snd_pcm_substream *substream,
187 struct snd_pcm_ 191 struct snd_pcm_hw_params *hw_params);
188 extern int snd_line6_hw_free(struct snd_pcm_su 192 extern int snd_line6_hw_free(struct snd_pcm_substream *substream);
189 extern snd_pcm_uframes_t snd_line6_pointer(str 193 extern snd_pcm_uframes_t snd_line6_pointer(struct snd_pcm_substream *substream);
190 extern void line6_pcm_disconnect(struct snd_li 194 extern void line6_pcm_disconnect(struct snd_line6_pcm *line6pcm);
191 extern int line6_pcm_acquire(struct snd_line6_ 195 extern int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int type,
192 bool start); 196 bool start);
193 extern void line6_pcm_release(struct snd_line6 197 extern void line6_pcm_release(struct snd_line6_pcm *line6pcm, int type);
194 198
195 #endif 199 #endif
196 200
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