sys/dev/midivar.h

   1 /*      $NetBSD: midivar.h,v 1.16 2008/03/05 10:48:48 cube Exp $        */
   2
   3 /*
   4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Lennart Augustsson (augustss@NetBSD.org) and (midi FST refactoring and
   9  * Active Sense) Chapman Flack (chap@NetBSD.org).
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  30  * POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #ifndef _SYS_DEV_MIDIVAR_H_
  34 #define _SYS_DEV_MIDIVAR_H_
  35
  36 #define MIDI_BUFSIZE 1024
  37
  38 #include "sequencer.h"
  39
  40 #include <sys/callout.h>
  41 #include <sys/cdefs.h>
  42 #include <sys/device.h>
  43 #include <sys/simplelock.h>
  44
  45 /*
  46  * In both xmt and rcv direction, the midi_fst runs at the time data are
  47  * buffered (midi_writebytes for xmt, midi_in for rcv) so what's in the
  48  * buffer is always in canonical form (or compressed, on xmt, if the hw
  49  * wants it that way). To preserve message boundaries for the buffer
  50  * consumer, but allow transfers larger than one message, the buffer is
  51  * split into a buf fork and an idx fork, where each byte of idx encodes
  52  * the type and length of a message. Because messages are variable length,
  53  * it is a guess how to set the relative sizes of idx and buf, or how many
  54  * messages can be buffered before one or the other fills.
  55  *
  56  * The producer adds only complete messages to a buffer (except for SysEx
  57  * messages, which have unpredictable length). A consumer serving byte-at-a-
  58  * time hardware may partially consume a message, in which case it updates
  59  * the length count at *idx_consumerp to reflect the remaining length of the
  60  * message, only incrementing idx_consumerp when the message has been entirely
  61  * consumed.
  62  *
  63  * The buffers are structured in the simple 1 reader 1 writer bounded buffer
  64  * form, considered full when 1 unused byte remains. This should allow their
  65  * use with minimal locking provided single pointer reads and writes can be
  66  * assured atomic ... but then I chickened out on assuming that assurance, and
  67  * added the extra locks to the code.
  68  *
  69  * Macros for manipulating the buffers:
  70  *
  71  * MIDI_BUF_DECLARE(frk) where frk is either buf or idx:
  72  *   declares the local variables frk_cur, frk_lim, frk_org, and frk_end.
  73  *
  74  * MIDI_BUF_CONSUMER_INIT(mb,frk)
  75  * MIDI_BUF_PRODUCER_INIT(mb,frk)
  76  *   initializes frk_org and frk_end to the base and end (that is, address just
  77  *   past the last valid byte) of the buffer fork frk, frk_cur to the
  78  *   consumer's or producer's current position, respectively, and frk_lim to
  79  *   the current limit (for either consumer or producer, immediately following
  80  *   this macro, frk_lim-frk_cur gives the number of bytes to play with). That
  81  *   means frk_lim may actually point past the buffer; loops on the condition
  82  *   (frk_cur < frk_lim) must contain WRAP(frk) if proceeding byte-by-byte, or
  83  *   must explicitly handle wrapping around frk_end if doing anything clever.
  84  *   These are expression-shaped macros that have the value frk_lim. When used
  85  *   without locking--provided pointer reads and writes can be assumed atomic--
  86  *   these macros give a conservative estimate of what is available to consume
  87  *   or produce.
  88  *
  89  * MIDI_BUF_WRAP(frk)
  90  *   tests whether frk_cur == frk_end and, if so, wraps both frk_cur and
  91  *   frk_lim around the beginning of the buffer. Because the test is ==, it
  92  *   must be applied at each byte in a loop; if the loop is proceeding in
  93  *   bigger steps, the possibility of wrap must be coded for. This expression-
  94  *   shaped macro has the value of frk_cur after wrapping.
  95  *
  96  * MIDI_BUF_CONSUMER_REFRESH(mb,frk)
  97  * MIDI_BUF_PRODUCER_REFRESH(mb,frk)
  98  *   refresh the local value frk_lim for a new snapshot of bytes available; an
  99  *   expression-shaped macro with the new value of frk_lim. Usually used after
 100  *   using up the first conservative estimate and obtaining a lock to get a
 101  *   final value. Used unlocked, just gives a more recent conservative estimate.
 102  *
 103  * MIDI_BUF_CONSUMER_WBACK(mb,frk)
 104  * MIDI_BUF_PRODUCER_WBACK(mb,frk)
 105  *   write back the local copy of frk_cur to the buffer, after a barrier to
 106  *   ensure prior writes go first. Under the right atomicity conditions a
 107  *   producer could get away with using these unlocked, as long as the order
 108  *   is buf followed by idx. A consumer should update both in a critical
 109  *   section.
 110  */
 111 struct midi_buffer {
 112         u_char * __volatile idx_producerp;
 113         u_char * __volatile idx_consumerp;
 114         u_char * __volatile buf_producerp;
 115         u_char * __volatile buf_consumerp;
 116         u_char idx[MIDI_BUFSIZE/3];
 117         u_char buf[MIDI_BUFSIZE-MIDI_BUFSIZE/3];
 118 };
 119 #define MIDI_BUF_DECLARE(frk) \
 120 u_char *__CONCAT(frk,_cur); \
 121 u_char *__CONCAT(frk,_lim); \
 122 u_char *__CONCAT(frk,_org); \
 123 u_char *__CONCAT(frk,_end)
 124
 125 #define MIDI_BUF_CONSUMER_REFRESH(mb,frk) \
 126 ((__CONCAT(frk,_lim)=(mb)->__CONCAT(frk,_producerp)), \
 127 __CONCAT(frk,_lim) < __CONCAT(frk,_cur) ? \
 128 (__CONCAT(frk,_lim) += sizeof (mb)->frk) : __CONCAT(frk,_lim))
 129
 130 #define MIDI_BUF_PRODUCER_REFRESH(mb,frk) \
 131 ((__CONCAT(frk,_lim)=(mb)->__CONCAT(frk,_consumerp)-1), \
 132 __CONCAT(frk,_lim) < __CONCAT(frk,_cur) ? \
 133 (__CONCAT(frk,_lim) += sizeof (mb)->frk) : __CONCAT(frk,_lim))
 134
 135 #define MIDI_BUF_EXTENT_INIT(mb,frk) \
 136 ((__CONCAT(frk,_org)=(mb)->frk), \
 137 (__CONCAT(frk,_end)=__CONCAT(frk,_org)+sizeof (mb)->frk))
 138
 139 #define MIDI_BUF_CONSUMER_INIT(mb,frk) \
 140 (MIDI_BUF_EXTENT_INIT((mb),frk), \
 141 (__CONCAT(frk,_cur)=(mb)->__CONCAT(frk,_consumerp)), \
 142 MIDI_BUF_CONSUMER_REFRESH((mb),frk))
 143
 144 #define MIDI_BUF_PRODUCER_INIT(mb,frk) \
 145 (MIDI_BUF_EXTENT_INIT((mb),frk), \
 146 (__CONCAT(frk,_cur)=(mb)->__CONCAT(frk,_producerp)), \
 147 MIDI_BUF_PRODUCER_REFRESH((mb),frk))
 148
 149 #define MIDI_BUF_WRAP(frk) \
 150 (__predict_false(__CONCAT(frk,_cur)==__CONCAT(frk,_end)) ? (\
 151 (__CONCAT(frk,_lim)-=__CONCAT(frk,_end)-__CONCAT(frk,_org)), \
 152 (__CONCAT(frk,_cur)=__CONCAT(frk,_org))) : __CONCAT(frk,_cur))
 153
 154 #define MIDI_BUF_CONSUMER_WBACK(mb,frk) do { \
 155 __insn_barrier(); \
 156 (mb)->__CONCAT(frk,_consumerp)=__CONCAT(frk,_cur); \
 157 } while (/*CONSTCOND*/0)
 158
 159 #define MIDI_BUF_PRODUCER_WBACK(mb,frk) do { \
 160 __insn_barrier(); \
 161 (mb)->__CONCAT(frk,_producerp)=__CONCAT(frk,_cur); \
 162 } while (/*CONSTCOND*/0)
 163
 164
 165 #define MIDI_MAX_WRITE 32       /* max bytes written with busy wait */
 166 #define MIDI_WAIT 10000         /* microseconds to wait after busy wait */
 167
 168 struct midi_state {
 169         struct  evcnt bytesDiscarded;
 170         struct  evcnt incompleteMessages;
 171         struct {
 172                 uint32_t bytesDiscarded;
 173                 uint32_t incompleteMessages;
 174         }       atOpen,
 175                 atQuery;
 176         int     state;
 177         u_char *pos;
 178         u_char *end;
 179         u_char  msg[3];
 180 };
 181
 182 struct midi_softc {
 183         device_t dev;
 184         void    *hw_hdl;        /* Hardware driver handle */
 185         const struct    midi_hw_if *hw_if; /* Hardware interface */
 186         const struct    midi_hw_if_ext *hw_if_ext; /* see midi_if.h */
 187         device_t sc_dev;        /* Hardware device struct */
 188         int     isopen;         /* Open indicator */
 189         int     flags;          /* Open flags */
 190         int     dying;
 191         struct  midi_buffer outbuf;
 192         struct  midi_buffer inbuf;
 193         int     props;
 194         int     rchan, wchan;
 195         struct  simplelock out_lock; /* overkill or no? */
 196         struct  simplelock in_lock;
 197
 198 #define MIDI_OUT_LOCK(sc,s) \
 199         do { \
 200                 (s) = splaudio(); \
 201                 simple_lock(&(sc)->out_lock); \
 202         } while (/*CONSTCOND*/0)
 203 #define MIDI_OUT_UNLOCK(sc,s) \
 204         do { \
 205                 simple_unlock(&(sc)->out_lock); \
 206                 splx((s)); \
 207         } while (/*CONSTCOND*/0)
 208 #define MIDI_IN_LOCK(sc,s) \
 209         do { \
 210                 (s) = splaudio(); \
 211                 simple_lock(&(sc)->in_lock); \
 212         } while (/*CONSTCOND*/0)
 213 #define MIDI_IN_UNLOCK(sc,s) \
 214         do { \
 215                 simple_unlock(&(sc)->in_lock); \
 216                 splx((s)); \
 217         } while (/*CONSTCOND*/0)
 218
 219         int     pbus;
 220         int     rcv_expect_asense;
 221         int     rcv_quiescent;
 222         int     rcv_eof;
 223         struct  selinfo wsel;   /* write selector */
 224         struct  selinfo rsel;   /* read selector */
 225         struct  proc *async;    /* process who wants audio SIGIO */
 226         void    *sih_rd;
 227         void    *sih_wr;
 228
 229         struct callout xmt_asense_co;
 230         struct callout rcv_asense_co;
 231
 232         /* MIDI input state machine; states are *s of 4 to allow | CAT bits */
 233         struct midi_state rcv;
 234         struct midi_state xmt;
 235 #define MIDI_IN_START   0
 236 #define MIDI_IN_RUN0_1  4
 237 #define MIDI_IN_RUN1_1  8
 238 #define MIDI_IN_RUN0_2 12
 239 #define MIDI_IN_RUN1_2 16
 240 #define MIDI_IN_RUN2_2 20
 241 #define MIDI_IN_COM0_1 24
 242 #define MIDI_IN_COM0_2 28
 243 #define MIDI_IN_COM1_2 32
 244 #define MIDI_IN_SYX1_3 36
 245 #define MIDI_IN_SYX2_3 40
 246 #define MIDI_IN_SYX0_3 44
 247 #define MIDI_IN_RNX0_1 48
 248 #define MIDI_IN_RNX0_2 52
 249 #define MIDI_IN_RNX1_2 56
 250 #define MIDI_IN_RNY1_2 60 /* not needed except for accurate error counts */
 251 /*
 252  * Four more states are needed to model the equivalence of NoteOff vel. 64
 253  * and NoteOn vel. 0 for canonicalization or compression. In each of these 4
 254  * states, we know the last message input and output was a NoteOn or a NoteOff.
 255  */
 256 #define MIDI_IN_RXX2_2 64 /* last output == msg[0] != last input */
 257 #define MIDI_IN_RXX0_2 68 /* last output != msg[0] == this input */
 258 #define MIDI_IN_RXX1_2 72 /* " */
 259 #define MIDI_IN_RXY1_2 76 /* variant of RXX1_2 needed for error count only */
 260
 261 #define MIDI_CAT_DATA 0
 262 #define MIDI_CAT_STATUS1 1
 263 #define MIDI_CAT_STATUS2 2
 264 #define MIDI_CAT_COMMON 3
 265
 266 #if NSEQUENCER > 0
 267         /* Synthesizer emulation stuff */
 268         int     seqopen;
 269         struct  midi_dev *seq_md; /* structure that links us with the seq. */
 270 #endif
 271 };
 272
 273 #define MIDIUNIT(d) ((d) & 0xff)
 274
 275 #endif /* _SYS_DEV_MIDIVAR_H_ */