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/slab.h>
  29 #include <linux/delay.h>
  30 #include <linux/ioport.h>
  31 #include <linux/errno.h>
  32 #include <sound/core.h>
  33 #include <sound/rawmidi.h>
  34
  35 #include "msnd.h"
  36
  37 #define MSNDMIDI_MODE_BIT_INPUT         0
  38 #define MSNDMIDI_MODE_BIT_OUTPUT                1
  39 #define MSNDMIDI_MODE_BIT_INPUT_TRIGGER 2
  40 #define MSNDMIDI_MODE_BIT_OUTPUT_TRIGGER        3
  41
  42 struct snd_msndmidi {
  43         struct snd_msnd *dev;
  44
  45         unsigned long mode;             /* MSNDMIDI_MODE_XXXX */
  46
  47         struct snd_rawmidi_substream *substream_input;
  48
  49         spinlock_t input_lock;
  50 };
  51
  52 /*
  53  * input/output open/close - protected by open_mutex in rawmidi.c
  54  */
  55 static int snd_msndmidi_input_open(struct snd_rawmidi_substream *substream)
  56 {
  57         struct snd_msndmidi *mpu;
  58
  59         snd_printdd("snd_msndmidi_input_open()\n");
  60
  61         mpu = substream->rmidi->private_data;
  62
  63         mpu->substream_input = substream;
  64
  65         snd_msnd_enable_irq(mpu->dev);
  66
  67         snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_START);
  68         set_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode);
  69         return 0;
  70 }
  71
  72 static int snd_msndmidi_input_close(struct snd_rawmidi_substream *substream)
  73 {
  74         struct snd_msndmidi *mpu;
  75
  76         mpu = substream->rmidi->private_data;
  77         snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_STOP);
  78         clear_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode);
  79         mpu->substream_input = NULL;
  80         snd_msnd_disable_irq(mpu->dev);
  81         return 0;
  82 }
  83
  84 static void snd_msndmidi_input_drop(struct snd_msndmidi *mpu)
  85 {
  86         u16 tail;
  87
  88         tail = readw(mpu->dev->MIDQ + JQS_wTail);
  89         writew(tail, mpu->dev->MIDQ + JQS_wHead);
  90 }
  91
  92 /*
  93  * trigger input
  94  */
  95 static void snd_msndmidi_input_trigger(struct snd_rawmidi_substream *substream,
  96                                         int up)
  97 {
  98         unsigned long flags;
  99         struct snd_msndmidi *mpu;
 100
 101         snd_printdd("snd_msndmidi_input_trigger(, %i)\n", up);
 102
 103         mpu = substream->rmidi->private_data;
 104         spin_lock_irqsave(&mpu->input_lock, flags);
 105         if (up) {
 106                 if (!test_and_set_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER,
 107                                       &mpu->mode))
 108                         snd_msndmidi_input_drop(mpu);
 109         } else {
 110                 clear_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
 111         }
 112         spin_unlock_irqrestore(&mpu->input_lock, flags);
 113         if (up)
 114                 snd_msndmidi_input_read(mpu);
 115 }
 116
 117 void snd_msndmidi_input_read(void *mpuv)
 118 {
 119         unsigned long flags;
 120         struct snd_msndmidi *mpu = mpuv;
 121         void *pwMIDQData = mpu->dev->mappedbase + MIDQ_DATA_BUFF;
 122
 123         spin_lock_irqsave(&mpu->input_lock, flags);
 124         while (readw(mpu->dev->MIDQ + JQS_wTail) !=
 125                readw(mpu->dev->MIDQ + JQS_wHead)) {
 126                 u16 wTmp, val;
 127                 val = readw(pwMIDQData + 2 * readw(mpu->dev->MIDQ + JQS_wHead));
 128
 129                         if (test_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER,
 130                                      &mpu->mode))
 131                                 snd_rawmidi_receive(mpu->substream_input,
 132                                                     (unsigned char *)&val, 1);
 133
 134                 wTmp = readw(mpu->dev->MIDQ + JQS_wHead) + 1;
 135                 if (wTmp > readw(mpu->dev->MIDQ + JQS_wSize))
 136                         writew(0,  mpu->dev->MIDQ + JQS_wHead);
 137                 else
 138                         writew(wTmp,  mpu->dev->MIDQ + JQS_wHead);
 139         }
 140         spin_unlock_irqrestore(&mpu->input_lock, flags);
 141 }
 142 EXPORT_SYMBOL(snd_msndmidi_input_read);
 143
 144 static struct snd_rawmidi_ops snd_msndmidi_input = {
 145         .open =         snd_msndmidi_input_open,
 146         .close =        snd_msndmidi_input_close,
 147         .trigger =      snd_msndmidi_input_trigger,
 148 };
 149
 150 static void snd_msndmidi_free(struct snd_rawmidi *rmidi)
 151 {
 152         struct snd_msndmidi *mpu = rmidi->private_data;
 153         kfree(mpu);
 154 }
 155
 156 int snd_msndmidi_new(struct snd_card *card, int device)
 157 {
 158         struct snd_msnd *chip = card->private_data;
 159         struct snd_msndmidi *mpu;
 160         struct snd_rawmidi *rmidi;
 161         int err;
 162
 163         err = snd_rawmidi_new(card, "MSND-MIDI", device, 1, 1, &rmidi);
 164         if (err < 0)
 165                 return err;
 166         mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
 167         if (mpu == NULL) {
 168                 snd_device_free(card, rmidi);
 169                 return -ENOMEM;
 170         }
 171         mpu->dev = chip;
 172         chip->msndmidi_mpu = mpu;
 173         rmidi->private_data = mpu;
 174         rmidi->private_free = snd_msndmidi_free;
 175         spin_lock_init(&mpu->input_lock);
 176         strcpy(rmidi->name, "MSND MIDI");
 177         snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
 178                             &snd_msndmidi_input);
 179         rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
 180         return 0;
 181 }