/* * Line 6 Linux USB driver * * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2. * */ #include <linux/slab.h> #include <linux/usb.h> #include <linux/export.h> #include <sound/core.h> #include <sound/rawmidi.h> #include "driver.h" #include "midi.h" #include "usbdefs.h" #define line6_rawmidi_substream_midi(substream) \ ((struct snd_line6_midi *)((substream)->rmidi->private_data)) static int send_midi_async(struct usb_line6 *line6, unsigned char *data, int length); /* Pass data received via USB to MIDI. */ void line6_midi_receive(struct usb_line6 *line6, unsigned char *data, int length) { if (line6->line6midi->substream_receive) snd_rawmidi_receive(line6->line6midi->substream_receive, data, length); } /* Read data from MIDI buffer and transmit them via USB. */ static void line6_midi_transmit(struct snd_rawmidi_substream *substream) { struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6; struct snd_line6_midi *line6midi = line6->line6midi; struct midi_buffer *mb = &line6midi->midibuf_out; unsigned char chunk[LINE6_FALLBACK_MAXPACKETSIZE]; int req, done; for (;;) { req = min(line6_midibuf_bytes_free(mb), line6->max_packet_size); done = snd_rawmidi_transmit_peek(substream, chunk, req); if (done == 0) break; line6_midibuf_write(mb, chunk, done); snd_rawmidi_transmit_ack(substream, done); } for (;;) { done = line6_midibuf_read(mb, chunk, LINE6_FALLBACK_MAXPACKETSIZE); if (done == 0) break; send_midi_async(line6, chunk, done); } } /* Notification of completion of MIDI transmission. */ static void midi_sent(struct urb *urb) { unsigned long flags; int status; int num; struct usb_line6 *line6 = (struct usb_line6 *)urb->context; status = urb->status; kfree(urb->transfer_buffer); usb_free_urb(urb); if (status == -ESHUTDOWN) return; spin_lock_irqsave(&line6->line6midi->lock, flags); num = --line6->line6midi->num_active_send_urbs; if (num == 0) { line6_midi_transmit(line6->line6midi->substream_transmit); num = line6->line6midi->num_active_send_urbs; } if (num == 0) wake_up(&line6->line6midi->send_wait); spin_unlock_irqrestore(&line6->line6midi->lock, flags); } /* Send an asynchronous MIDI message. Assumes that line6->line6midi->lock is held (i.e., this function is serialized). */ static int send_midi_async(struct usb_line6 *line6, unsigned char *data, int length) { struct urb *urb; int retval; unsigned char *transfer_buffer; urb = usb_alloc_urb(0, GFP_ATOMIC); if (urb == NULL) return -ENOMEM; transfer_buffer = kmemdup(data, length, GFP_ATOMIC); if (transfer_buffer == NULL) { usb_free_urb(urb); return -ENOMEM; } usb_fill_int_urb(urb, line6->usbdev, usb_sndbulkpipe(line6->usbdev, line6->properties->ep_ctrl_w), transfer_buffer, length, midi_sent, line6, line6->interval); urb->actual_length = 0; retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval < 0) { dev_err(line6->ifcdev, "usb_submit_urb failed\n"); usb_free_urb(urb); return retval; } ++line6->line6midi->num_active_send_urbs; return 0; } static int line6_midi_output_open(struct snd_rawmidi_substream *substream) { return 0; } static int line6_midi_output_close(struct snd_rawmidi_substream *substream) { return 0; } static void line6_midi_output_trigger(struct snd_rawmidi_substream *substream, int up) { unsigned long flags; struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6; line6->line6midi->substream_transmit = substream; spin_lock_irqsave(&line6->line6midi->lock, flags); if (line6->line6midi->num_active_send_urbs == 0) line6_midi_transmit(substream); spin_unlock_irqrestore(&line6->line6midi->lock, flags); } static void line6_midi_output_drain(struct snd_rawmidi_substream *substream) { struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6; struct snd_line6_midi *midi = line6->line6midi; wait_event_interruptible(midi->send_wait, midi->num_active_send_urbs == 0); } static int line6_midi_input_open(struct snd_rawmidi_substream *substream) { return 0; } static int line6_midi_input_close(struct snd_rawmidi_substream *substream) { return 0; } static void line6_midi_input_trigger(struct snd_rawmidi_substream *substream, int up) { struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6; if (up) line6->line6midi->substream_receive = substream; else line6->line6midi->substream_receive = NULL; } static struct snd_rawmidi_ops line6_midi_output_ops = { .open = line6_midi_output_open, .close = line6_midi_output_close, .trigger = line6_midi_output_trigger, .drain = line6_midi_output_drain, }; static struct snd_rawmidi_ops line6_midi_input_ops = { .open = line6_midi_input_open, .close = line6_midi_input_close, .trigger = line6_midi_input_trigger, }; /* Create a MIDI device */ static int snd_line6_new_midi(struct usb_line6 *line6, struct snd_rawmidi **rmidi_ret) { struct snd_rawmidi *rmidi; int err; err = snd_rawmidi_new(line6->card, "Line 6 MIDI", 0, 1, 1, rmidi_ret); if (err < 0) return err; rmidi = *rmidi_ret; strcpy(rmidi->id, line6->properties->id); strcpy(rmidi->name, line6->properties->name); rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX; snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &line6_midi_output_ops); snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &line6_midi_input_ops); return 0; } /* MIDI device destructor */ static void snd_line6_midi_free(struct snd_rawmidi *rmidi) { struct snd_line6_midi *line6midi = rmidi->private_data; line6_midibuf_destroy(&line6midi->midibuf_in); line6_midibuf_destroy(&line6midi->midibuf_out); kfree(line6midi); } /* Initialize the Line 6 MIDI subsystem. */ int line6_init_midi(struct usb_line6 *line6) { int err; struct snd_rawmidi *rmidi; struct snd_line6_midi *line6midi; if (!(line6->properties->capabilities & LINE6_CAP_CONTROL)) { /* skip MIDI initialization and report success */ return 0; } err = snd_line6_new_midi(line6, &rmidi); if (err < 0) return err; line6midi = kzalloc(sizeof(struct snd_line6_midi), GFP_KERNEL); if (!line6midi) return -ENOMEM; rmidi->private_data = line6midi; rmidi->private_free = snd_line6_midi_free; init_waitqueue_head(&line6midi->send_wait); spin_lock_init(&line6midi->lock); line6midi->line6 = line6; err = line6_midibuf_init(&line6midi->midibuf_in, MIDI_BUFFER_SIZE, 0); if (err < 0) return err; err = line6_midibuf_init(&line6midi->midibuf_out, MIDI_BUFFER_SIZE, 1); if (err < 0) return err; line6->line6midi = line6midi; return 0; } EXPORT_SYMBOL_GPL(line6_init_midi);