sound/isa/msnd/msnd_midi.c

   1 /*
   2  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   3  *  Copyright (c) 2009 by Krzysztof Helt
   4  *  Routines for control of MPU-401 in UART mode
   5  *
   6  *  MPU-401 supports UART mode which is not capable generate transmit
   7  *  interrupts thus output is done via polling. Also, if irq < 0, then
   8  *  input is done also via polling. Do not expect good performance.
   9  *
  10  *
  11  *   This program is free software; you can redistribute it and/or modify
  12  *   it under the terms of the GNU General Public License as published by
  13  *   the Free Software Foundation; either version 2 of the License, or
  14  *   (at your option) any later version.
  15  *
  16  *   This program is distributed in the hope that it will be useful,
  17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *   GNU General Public License for more details.
  20  *
  21  *   You should have received a copy of the GNU General Public License
  22  *   along with this program; if not, write to the Free Software
  23  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  24  *
  25  */
  26
  27 #include <linux/io.h>
  28 #include <linux/delay.h>
  29 #include <linux/ioport.h>
  30 #include <linux/errno.h>
  31 #include <sound/core.h>
  32 #include <sound/rawmidi.h>
  33
  34 #include "msnd.h"
  35
  36 #define MSNDMIDI_MODE_BIT_INPUT         0
  37 #define MSNDMIDI_MODE_BIT_OUTPUT                1
  38 #define MSNDMIDI_MODE_BIT_INPUT_TRIGGER 2
  39 #define MSNDMIDI_MODE_BIT_OUTPUT_TRIGGER        3
  40
  41 struct snd_msndmidi {
  42         struct snd_msnd *dev;
  43
  44         unsigned long mode;             /* MSNDMIDI_MODE_XXXX */
  45
  46         struct snd_rawmidi_substream *substream_input;
  47
  48         spinlock_t input_lock;
  49 };
  50
  51 /*
  52  * input/output open/close - protected by open_mutex in rawmidi.c
  53  */
  54 static int snd_msndmidi_input_open(struct snd_rawmidi_substream *substream)
  55 {
  56         struct snd_msndmidi *mpu;
  57
  58         snd_printdd("snd_msndmidi_input_open()\n");
  59
  60         mpu = substream->rmidi->private_data;
  61
  62         mpu->substream_input = substream;
  63
  64         snd_msnd_enable_irq(mpu->dev);
  65
  66         snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_START);
  67         set_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode);
  68         return 0;
  69 }
  70
  71 static int snd_msndmidi_input_close(struct snd_rawmidi_substream *substream)
  72 {
  73         struct snd_msndmidi *mpu;
  74
  75         mpu = substream->rmidi->private_data;
  76         snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_STOP);
  77         clear_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode);
  78         mpu->substream_input = NULL;
  79         snd_msnd_disable_irq(mpu->dev);
  80         return 0;
  81 }
  82
  83 static void snd_msndmidi_input_drop(struct snd_msndmidi *mpu)
  84 {
  85         u16 tail;
  86
  87         tail = readw(mpu->dev->MIDQ + JQS_wTail);
  88         writew(tail, mpu->dev->MIDQ + JQS_wHead);
  89 }
  90
  91 /*
  92  * trigger input
  93  */
  94 static void snd_msndmidi_input_trigger(struct snd_rawmidi_substream *substream,
  95                                         int up)
  96 {
  97         unsigned long flags;
  98         struct snd_msndmidi *mpu;
  99
 100         snd_printdd("snd_msndmidi_input_trigger(, %i)\n", up);
 101
 102         mpu = substream->rmidi->private_data;
 103         spin_lock_irqsave(&mpu->input_lock, flags);
 104         if (up) {
 105                 if (!test_and_set_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER,
 106                                       &mpu->mode))
 107                         snd_msndmidi_input_drop(mpu);
 108         } else {
 109                 clear_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
 110         }
 111         spin_unlock_irqrestore(&mpu->input_lock, flags);
 112         if (up)
 113                 snd_msndmidi_input_read(mpu);
 114 }
 115
 116 void snd_msndmidi_input_read(void *mpuv)
 117 {
 118         unsigned long flags;
 119         struct snd_msndmidi *mpu = mpuv;
 120         void *pwMIDQData = mpu->dev->mappedbase + MIDQ_DATA_BUFF;
 121
 122         spin_lock_irqsave(&mpu->input_lock, flags);
 123         while (readw(mpu->dev->MIDQ + JQS_wTail) !=
 124                readw(mpu->dev->MIDQ + JQS_wHead)) {
 125                 u16 wTmp, val;
 126                 val = readw(pwMIDQData + 2 * readw(mpu->dev->MIDQ + JQS_wHead));
 127
 128                         if (test_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER,
 129                                      &mpu->mode))
 130                                 snd_rawmidi_receive(mpu->substream_input,
 131                                                     (unsigned char *)&val, 1);
 132
 133                 wTmp = readw(mpu->dev->MIDQ + JQS_wHead) + 1;
 134                 if (wTmp > readw(mpu->dev->MIDQ + JQS_wSize))
 135                         writew(0,  mpu->dev->MIDQ + JQS_wHead);
 136                 else
 137                         writew(wTmp,  mpu->dev->MIDQ + JQS_wHead);
 138         }
 139         spin_unlock_irqrestore(&mpu->input_lock, flags);
 140 }
 141 EXPORT_SYMBOL(snd_msndmidi_input_read);
 142
 143 static struct snd_rawmidi_ops snd_msndmidi_input = {
 144         .open =         snd_msndmidi_input_open,
 145         .close =        snd_msndmidi_input_close,
 146         .trigger =      snd_msndmidi_input_trigger,
 147 };
 148
 149 static void snd_msndmidi_free(struct snd_rawmidi *rmidi)
 150 {
 151         struct snd_msndmidi *mpu = rmidi->private_data;
 152         kfree(mpu);
 153 }
 154
 155 int snd_msndmidi_new(struct snd_card *card, int device)
 156 {
 157         struct snd_msnd *chip = card->private_data;
 158         struct snd_msndmidi *mpu;
 159         struct snd_rawmidi *rmidi;
 160         int err;
 161
 162         err = snd_rawmidi_new(card, "MSND-MIDI", device, 1, 1, &rmidi);
 163         if (err < 0)
 164                 return err;
 165         mpu = kcalloc(1, sizeof(*mpu), GFP_KERNEL);
 166         if (mpu == NULL) {
 167                 snd_device_free(card, rmidi);
 168                 return -ENOMEM;
 169         }
 170         mpu->dev = chip;
 171         chip->msndmidi_mpu = mpu;
 172         rmidi->private_data = mpu;
 173         rmidi->private_free = snd_msndmidi_free;
 174         spin_lock_init(&mpu->input_lock);
 175         strcpy(rmidi->name, "MSND MIDI");
 176         snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
 177                             &snd_msndmidi_input);
 178         rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
 179         return 0;
 180 }