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 <linux/export.h> 33 #include <sound/core.h> 34 #include <sound/rawmidi.h> 35 36 #include "msnd.h" 37 38 #define MSNDMIDI_MODE_BIT_INPUT 0 39 #define MSNDMIDI_MODE_BIT_OUTPUT 1 40 #define MSNDMIDI_MODE_BIT_INPUT_TRIGGER 2 41 #define MSNDMIDI_MODE_BIT_OUTPUT_TRIGGER 3 42 43 struct snd_msndmidi { 44 struct snd_msnd *dev; 45 46 unsigned long mode; /* MSNDMIDI_MODE_XXXX */ 47 48 struct snd_rawmidi_substream *substream_input; 49 50 spinlock_t input_lock; 51 }; 52 53 /* 54 * input/output open/close - protected by open_mutex in rawmidi.c 55 */ 56 static int snd_msndmidi_input_open(struct snd_rawmidi_substream *substream) 57 { 58 struct snd_msndmidi *mpu; 59 60 snd_printdd("snd_msndmidi_input_open()\n"); 61 62 mpu = substream->rmidi->private_data; 63 64 mpu->substream_input = substream; 65 66 snd_msnd_enable_irq(mpu->dev); 67 68 snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_START); 69 set_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode); 70 return 0; 71 } 72 73 static int snd_msndmidi_input_close(struct snd_rawmidi_substream *substream) 74 { 75 struct snd_msndmidi *mpu; 76 77 mpu = substream->rmidi->private_data; 78 snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_STOP); 79 clear_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode); 80 mpu->substream_input = NULL; 81 snd_msnd_disable_irq(mpu->dev); 82 return 0; 83 } 84 85 static void snd_msndmidi_input_drop(struct snd_msndmidi *mpu) 86 { 87 u16 tail; 88 89 tail = readw(mpu->dev->MIDQ + JQS_wTail); 90 writew(tail, mpu->dev->MIDQ + JQS_wHead); 91 } 92 93 /* 94 * trigger input 95 */ 96 static void snd_msndmidi_input_trigger(struct snd_rawmidi_substream *substream, 97 int up) 98 { 99 unsigned long flags; 100 struct snd_msndmidi *mpu; 101 102 snd_printdd("snd_msndmidi_input_trigger(, %i)\n", up); 103 104 mpu = substream->rmidi->private_data; 105 spin_lock_irqsave(&mpu->input_lock, flags); 106 if (up) { 107 if (!test_and_set_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, 108 &mpu->mode)) 109 snd_msndmidi_input_drop(mpu); 110 } else { 111 clear_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode); 112 } 113 spin_unlock_irqrestore(&mpu->input_lock, flags); 114 if (up) 115 snd_msndmidi_input_read(mpu); 116 } 117 118 void snd_msndmidi_input_read(void *mpuv) 119 { 120 unsigned long flags; 121 struct snd_msndmidi *mpu = mpuv; 122 void __iomem *pwMIDQData = mpu->dev->mappedbase + MIDQ_DATA_BUFF; 123 u16 head, tail, size; 124 125 spin_lock_irqsave(&mpu->input_lock, flags); 126 head = readw(mpu->dev->MIDQ + JQS_wHead); 127 tail = readw(mpu->dev->MIDQ + JQS_wTail); 128 size = readw(mpu->dev->MIDQ + JQS_wSize); 129 if (head > size || tail > size) 130 goto out; 131 while (head != tail) { 132 unsigned char val = readw(pwMIDQData + 2 * head); 133 134 if (test_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) 135 snd_rawmidi_receive(mpu->substream_input, &val, 1); 136 if (++head > size) 137 head = 0; 138 writew(head, mpu->dev->MIDQ + JQS_wHead); 139 } 140 out: 141 spin_unlock_irqrestore(&mpu->input_lock, flags); 142 } 143 EXPORT_SYMBOL(snd_msndmidi_input_read); 144 145 static const struct snd_rawmidi_ops snd_msndmidi_input = { 146 .open = snd_msndmidi_input_open, 147 .close = snd_msndmidi_input_close, 148 .trigger = snd_msndmidi_input_trigger, 149 }; 150 151 static void snd_msndmidi_free(struct snd_rawmidi *rmidi) 152 { 153 struct snd_msndmidi *mpu = rmidi->private_data; 154 kfree(mpu); 155 } 156 157 int snd_msndmidi_new(struct snd_card *card, int device) 158 { 159 struct snd_msnd *chip = card->private_data; 160 struct snd_msndmidi *mpu; 161 struct snd_rawmidi *rmidi; 162 int err; 163 164 err = snd_rawmidi_new(card, "MSND-MIDI", device, 1, 1, &rmidi); 165 if (err < 0) 166 return err; 167 mpu = kzalloc(sizeof(*mpu), GFP_KERNEL); 168 if (mpu == NULL) { 169 snd_device_free(card, rmidi); 170 return -ENOMEM; 171 } 172 mpu->dev = chip; 173 chip->msndmidi_mpu = mpu; 174 rmidi->private_data = mpu; 175 rmidi->private_free = snd_msndmidi_free; 176 spin_lock_init(&mpu->input_lock); 177 strcpy(rmidi->name, "MSND MIDI"); 178 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, 179 &snd_msndmidi_input); 180 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT; 181 return 0; 182 } 183