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 21 #define line6_rawmidi_substream_midi(substream) \ 22 ((struct snd_line6_midi *)((substream)->rmidi->private_data)) 23 24 static int send_midi_async(struct usb_line6 *line6, unsigned char *data, 25 int length); 26 27 /* 28 Pass data received via USB to MIDI. 29 */ 30 void line6_midi_receive(struct usb_line6 *line6, unsigned char *data, 31 int length) 32 { 33 if (line6->line6midi->substream_receive) 34 snd_rawmidi_receive(line6->line6midi->substream_receive, 35 data, length); 36 } 37 38 /* 39 Read data from MIDI buffer and transmit them via USB. 40 */ 41 static void line6_midi_transmit(struct snd_rawmidi_substream *substream) 42 { 43 struct usb_line6 *line6 = 44 line6_rawmidi_substream_midi(substream)->line6; 45 struct snd_line6_midi *line6midi = line6->line6midi; 46 struct midi_buffer *mb = &line6midi->midibuf_out; 47 unsigned char chunk[LINE6_FALLBACK_MAXPACKETSIZE]; 48 int req, done; 49 50 for (;;) { 51 req = min(line6_midibuf_bytes_free(mb), line6->max_packet_size); 52 done = snd_rawmidi_transmit_peek(substream, chunk, req); 53 54 if (done == 0) 55 break; 56 57 line6_midibuf_write(mb, chunk, done); 58 snd_rawmidi_transmit_ack(substream, done); 59 } 60 61 for (;;) { 62 done = line6_midibuf_read(mb, chunk, 63 LINE6_FALLBACK_MAXPACKETSIZE); 64 65 if (done == 0) 66 break; 67 68 send_midi_async(line6, chunk, done); 69 } 70 } 71 72 /* 73 Notification of completion of MIDI transmission. 74 */ 75 static void midi_sent(struct urb *urb) 76 { 77 unsigned long flags; 78 int status; 79 int num; 80 struct usb_line6 *line6 = (struct usb_line6 *)urb->context; 81 82 status = urb->status; 83 kfree(urb->transfer_buffer); 84 usb_free_urb(urb); 85 86 if (status == -ESHUTDOWN) 87 return; 88 89 spin_lock_irqsave(&line6->line6midi->lock, flags); 90 num = --line6->line6midi->num_active_send_urbs; 91 92 if (num == 0) { 93 line6_midi_transmit(line6->line6midi->substream_transmit); 94 num = line6->line6midi->num_active_send_urbs; 95 } 96 97 if (num == 0) 98 wake_up(&line6->line6midi->send_wait); 99 100 spin_unlock_irqrestore(&line6->line6midi->lock, flags); 101 } 102 103 /* 104 Send an asynchronous MIDI message. 105 Assumes that line6->line6midi->lock is held 106 (i.e., this function is serialized). 107 */ 108 static int send_midi_async(struct usb_line6 *line6, unsigned char *data, 109 int length) 110 { 111 struct urb *urb; 112 int retval; 113 unsigned char *transfer_buffer; 114 115 urb = usb_alloc_urb(0, GFP_ATOMIC); 116 117 if (urb == NULL) 118 return -ENOMEM; 119 120 transfer_buffer = kmemdup(data, length, GFP_ATOMIC); 121 122 if (transfer_buffer == NULL) { 123 usb_free_urb(urb); 124 return -ENOMEM; 125 } 126 127 usb_fill_int_urb(urb, line6->usbdev, 128 usb_sndbulkpipe(line6->usbdev, 129 line6->properties->ep_ctrl_w), 130 transfer_buffer, length, midi_sent, line6, 131 line6->interval); 132 urb->actual_length = 0; 133 retval = usb_urb_ep_type_check(urb); 134 if (retval < 0) 135 goto error; 136 137 retval = usb_submit_urb(urb, GFP_ATOMIC); 138 if (retval < 0) 139 goto error; 140 141 ++line6->line6midi->num_active_send_urbs; 142 return 0; 143 144 error: 145 dev_err(line6->ifcdev, "usb_submit_urb failed\n"); 146 usb_free_urb(urb); 147 return retval; 148 } 149 150 static int line6_midi_output_open(struct snd_rawmidi_substream *substream) 151 { 152 return 0; 153 } 154 155 static int line6_midi_output_close(struct snd_rawmidi_substream *substream) 156 { 157 return 0; 158 } 159 160 static void line6_midi_output_trigger(struct snd_rawmidi_substream *substream, 161 int up) 162 { 163 unsigned long flags; 164 struct usb_line6 *line6 = 165 line6_rawmidi_substream_midi(substream)->line6; 166 167 line6->line6midi->substream_transmit = substream; 168 spin_lock_irqsave(&line6->line6midi->lock, flags); 169 170 if (line6->line6midi->num_active_send_urbs == 0) 171 line6_midi_transmit(substream); 172 173 spin_unlock_irqrestore(&line6->line6midi->lock, flags); 174 } 175 176 static void line6_midi_output_drain(struct snd_rawmidi_substream *substream) 177 { 178 struct usb_line6 *line6 = 179 line6_rawmidi_substream_midi(substream)->line6; 180 struct snd_line6_midi *midi = line6->line6midi; 181 182 wait_event_interruptible(midi->send_wait, 183 midi->num_active_send_urbs == 0); 184 } 185 186 static int line6_midi_input_open(struct snd_rawmidi_substream *substream) 187 { 188 return 0; 189 } 190 191 static int line6_midi_input_close(struct snd_rawmidi_substream *substream) 192 { 193 return 0; 194 } 195 196 static void line6_midi_input_trigger(struct snd_rawmidi_substream *substream, 197 int up) 198 { 199 struct usb_line6 *line6 = 200 line6_rawmidi_substream_midi(substream)->line6; 201 202 if (up) 203 line6->line6midi->substream_receive = substream; 204 else 205 line6->line6midi->substream_receive = NULL; 206 } 207 208 static const struct snd_rawmidi_ops line6_midi_output_ops = { 209 .open = line6_midi_output_open, 210 .close = line6_midi_output_close, 211 .trigger = line6_midi_output_trigger, 212 .drain = line6_midi_output_drain, 213 }; 214 215 static const struct snd_rawmidi_ops line6_midi_input_ops = { 216 .open = line6_midi_input_open, 217 .close = line6_midi_input_close, 218 .trigger = line6_midi_input_trigger, 219 }; 220 221 /* Create a MIDI device */ 222 static int snd_line6_new_midi(struct usb_line6 *line6, 223 struct snd_rawmidi **rmidi_ret) 224 { 225 struct snd_rawmidi *rmidi; 226 int err; 227 228 err = snd_rawmidi_new(line6->card, "Line 6 MIDI", 0, 1, 1, rmidi_ret); 229 if (err < 0) 230 return err; 231 232 rmidi = *rmidi_ret; 233 strcpy(rmidi->id, line6->properties->id); 234 strcpy(rmidi->name, line6->properties->name); 235 236 rmidi->info_flags = 237 SNDRV_RAWMIDI_INFO_OUTPUT | 238 SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX; 239 240 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, 241 &line6_midi_output_ops); 242 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, 243 &line6_midi_input_ops); 244 return 0; 245 } 246 247 /* MIDI device destructor */ 248 static void snd_line6_midi_free(struct snd_rawmidi *rmidi) 249 { 250 struct snd_line6_midi *line6midi = rmidi->private_data; 251 252 line6_midibuf_destroy(&line6midi->midibuf_in); 253 line6_midibuf_destroy(&line6midi->midibuf_out); 254 kfree(line6midi); 255 } 256 257 /* 258 Initialize the Line 6 MIDI subsystem. 259 */ 260 int line6_init_midi(struct usb_line6 *line6) 261 { 262 int err; 263 struct snd_rawmidi *rmidi; 264 struct snd_line6_midi *line6midi; 265 266 if (!(line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI)) { 267 /* skip MIDI initialization and report success */ 268 return 0; 269 } 270 271 err = snd_line6_new_midi(line6, &rmidi); 272 if (err < 0) 273 return err; 274 275 line6midi = kzalloc(sizeof(struct snd_line6_midi), GFP_KERNEL); 276 if (!line6midi) 277 return -ENOMEM; 278 279 rmidi->private_data = line6midi; 280 rmidi->private_free = snd_line6_midi_free; 281 282 init_waitqueue_head(&line6midi->send_wait); 283 spin_lock_init(&line6midi->lock); 284 line6midi->line6 = line6; 285 286 err = line6_midibuf_init(&line6midi->midibuf_in, MIDI_BUFFER_SIZE, 0); 287 if (err < 0) 288 return err; 289 290 err = line6_midibuf_init(&line6midi->midibuf_out, MIDI_BUFFER_SIZE, 1); 291 if (err < 0) 292 return err; 293 294 line6->line6midi = line6midi; 295 return 0; 296 } 297 EXPORT_SYMBOL_GPL(line6_init_midi); 298