1 /* 2 * Line 6 Linux USB driver 3 * 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 * 10 */ 11 12 #include <linux/slab.h> 13 #include <linux/usb.h> 14 #include <linux/export.h> 15 #include <sound/core.h> 16 #include <sound/rawmidi.h> 17 18 #include "driver.h" 19 #include "midi.h" 20 #include "usbdefs.h" 21 22 #define line6_rawmidi_substream_midi(substream) \ 23 ((struct snd_line6_midi *)((substream)->rmidi->private_data)) 24 25 static int send_midi_async(struct usb_line6 *line6, unsigned char *data, 26 int length); 27 28 /* 29 Pass data received via USB to MIDI. 30 */ 31 void line6_midi_receive(struct usb_line6 *line6, unsigned char *data, 32 int length) 33 { 34 if (line6->line6midi->substream_receive) 35 snd_rawmidi_receive(line6->line6midi->substream_receive, 36 data, length); 37 } 38 39 /* 40 Read data from MIDI buffer and transmit them via USB. 41 */ 42 static void line6_midi_transmit(struct snd_rawmidi_substream *substream) 43 { 44 struct usb_line6 *line6 = 45 line6_rawmidi_substream_midi(substream)->line6; 46 struct snd_line6_midi *line6midi = line6->line6midi; 47 struct midi_buffer *mb = &line6midi->midibuf_out; 48 unsigned char chunk[LINE6_FALLBACK_MAXPACKETSIZE]; 49 int req, done; 50 51 for (;;) { 52 req = min(line6_midibuf_bytes_free(mb), line6->max_packet_size); 53 done = snd_rawmidi_transmit_peek(substream, chunk, req); 54 55 if (done == 0) 56 break; 57 58 line6_midibuf_write(mb, chunk, done); 59 snd_rawmidi_transmit_ack(substream, done); 60 } 61 62 for (;;) { 63 done = line6_midibuf_read(mb, chunk, 64 LINE6_FALLBACK_MAXPACKETSIZE); 65 66 if (done == 0) 67 break; 68 69 send_midi_async(line6, chunk, done); 70 } 71 } 72 73 /* 74 Notification of completion of MIDI transmission. 75 */ 76 static void midi_sent(struct urb *urb) 77 { 78 unsigned long flags; 79 int status; 80 int num; 81 struct usb_line6 *line6 = (struct usb_line6 *)urb->context; 82 83 status = urb->status; 84 kfree(urb->transfer_buffer); 85 usb_free_urb(urb); 86 87 if (status == -ESHUTDOWN) 88 return; 89 90 spin_lock_irqsave(&line6->line6midi->lock, flags); 91 num = --line6->line6midi->num_active_send_urbs; 92 93 if (num == 0) { 94 line6_midi_transmit(line6->line6midi->substream_transmit); 95 num = line6->line6midi->num_active_send_urbs; 96 } 97 98 if (num == 0) 99 wake_up(&line6->line6midi->send_wait); 100 101 spin_unlock_irqrestore(&line6->line6midi->lock, flags); 102 } 103 104 /* 105 Send an asynchronous MIDI message. 106 Assumes that line6->line6midi->lock is held 107 (i.e., this function is serialized). 108 */ 109 static int send_midi_async(struct usb_line6 *line6, unsigned char *data, 110 int length) 111 { 112 struct urb *urb; 113 int retval; 114 unsigned char *transfer_buffer; 115 116 urb = usb_alloc_urb(0, GFP_ATOMIC); 117 118 if (urb == NULL) 119 return -ENOMEM; 120 121 transfer_buffer = kmemdup(data, length, GFP_ATOMIC); 122 123 if (transfer_buffer == NULL) { 124 usb_free_urb(urb); 125 return -ENOMEM; 126 } 127 128 usb_fill_int_urb(urb, line6->usbdev, 129 usb_sndbulkpipe(line6->usbdev, 130 line6->properties->ep_ctrl_w), 131 transfer_buffer, length, midi_sent, line6, 132 line6->interval); 133 urb->actual_length = 0; 134 retval = usb_submit_urb(urb, GFP_ATOMIC); 135 136 if (retval < 0) { 137 dev_err(line6->ifcdev, "usb_submit_urb failed\n"); 138 usb_free_urb(urb); 139 return retval; 140 } 141 142 ++line6->line6midi->num_active_send_urbs; 143 return 0; 144 } 145 146 static int line6_midi_output_open(struct snd_rawmidi_substream *substream) 147 { 148 return 0; 149 } 150 151 static int line6_midi_output_close(struct snd_rawmidi_substream *substream) 152 { 153 return 0; 154 } 155 156 static void line6_midi_output_trigger(struct snd_rawmidi_substream *substream, 157 int up) 158 { 159 unsigned long flags; 160 struct usb_line6 *line6 = 161 line6_rawmidi_substream_midi(substream)->line6; 162 163 line6->line6midi->substream_transmit = substream; 164 spin_lock_irqsave(&line6->line6midi->lock, flags); 165 166 if (line6->line6midi->num_active_send_urbs == 0) 167 line6_midi_transmit(substream); 168 169 spin_unlock_irqrestore(&line6->line6midi->lock, flags); 170 } 171 172 static void line6_midi_output_drain(struct snd_rawmidi_substream *substream) 173 { 174 struct usb_line6 *line6 = 175 line6_rawmidi_substream_midi(substream)->line6; 176 struct snd_line6_midi *midi = line6->line6midi; 177 178 wait_event_interruptible(midi->send_wait, 179 midi->num_active_send_urbs == 0); 180 } 181 182 static int line6_midi_input_open(struct snd_rawmidi_substream *substream) 183 { 184 return 0; 185 } 186 187 static int line6_midi_input_close(struct snd_rawmidi_substream *substream) 188 { 189 return 0; 190 } 191 192 static void line6_midi_input_trigger(struct snd_rawmidi_substream *substream, 193 int up) 194 { 195 struct usb_line6 *line6 = 196 line6_rawmidi_substream_midi(substream)->line6; 197 198 if (up) 199 line6->line6midi->substream_receive = substream; 200 else 201 line6->line6midi->substream_receive = NULL; 202 } 203 204 static struct snd_rawmidi_ops line6_midi_output_ops = { 205 .open = line6_midi_output_open, 206 .close = line6_midi_output_close, 207 .trigger = line6_midi_output_trigger, 208 .drain = line6_midi_output_drain, 209 }; 210 211 static struct snd_rawmidi_ops line6_midi_input_ops = { 212 .open = line6_midi_input_open, 213 .close = line6_midi_input_close, 214 .trigger = line6_midi_input_trigger, 215 }; 216 217 /* Create a MIDI device */ 218 static int snd_line6_new_midi(struct usb_line6 *line6, 219 struct snd_rawmidi **rmidi_ret) 220 { 221 struct snd_rawmidi *rmidi; 222 int err; 223 224 err = snd_rawmidi_new(line6->card, "Line 6 MIDI", 0, 1, 1, rmidi_ret); 225 if (err < 0) 226 return err; 227 228 rmidi = *rmidi_ret; 229 strcpy(rmidi->id, line6->properties->id); 230 strcpy(rmidi->name, line6->properties->name); 231 232 rmidi->info_flags = 233 SNDRV_RAWMIDI_INFO_OUTPUT | 234 SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX; 235 236 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, 237 &line6_midi_output_ops); 238 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, 239 &line6_midi_input_ops); 240 return 0; 241 } 242 243 /* MIDI device destructor */ 244 static void snd_line6_midi_free(struct snd_rawmidi *rmidi) 245 { 246 struct snd_line6_midi *line6midi = rmidi->private_data; 247 248 line6_midibuf_destroy(&line6midi->midibuf_in); 249 line6_midibuf_destroy(&line6midi->midibuf_out); 250 kfree(line6midi); 251 } 252 253 /* 254 Initialize the Line 6 MIDI subsystem. 255 */ 256 int line6_init_midi(struct usb_line6 *line6) 257 { 258 int err; 259 struct snd_rawmidi *rmidi; 260 struct snd_line6_midi *line6midi; 261 262 if (!(line6->properties->capabilities & LINE6_CAP_CONTROL)) { 263 /* skip MIDI initialization and report success */ 264 return 0; 265 } 266 267 err = snd_line6_new_midi(line6, &rmidi); 268 if (err < 0) 269 return err; 270 271 line6midi = kzalloc(sizeof(struct snd_line6_midi), GFP_KERNEL); 272 if (!line6midi) 273 return -ENOMEM; 274 275 rmidi->private_data = line6midi; 276 rmidi->private_free = snd_line6_midi_free; 277 278 init_waitqueue_head(&line6midi->send_wait); 279 spin_lock_init(&line6midi->lock); 280 line6midi->line6 = line6; 281 282 err = line6_midibuf_init(&line6midi->midibuf_in, MIDI_BUFFER_SIZE, 0); 283 if (err < 0) 284 return err; 285 286 err = line6_midibuf_init(&line6midi->midibuf_out, MIDI_BUFFER_SIZE, 1); 287 if (err < 0) 288 return err; 289 290 line6->line6midi = line6midi; 291 return 0; 292 } 293 EXPORT_SYMBOL_GPL(line6_init_midi); 294