midi.c
/*
* Linux driver for TerraTec DMX 6Fire USB
*
* Rawmidi driver
*
* Author: Torsten Schenk <torsten.schenk@zoho.com>
* Created: Jan 01, 2011
* Copyright: (C) Torsten Schenk
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*/
#include <sound/rawmidi.h>
#include "midi.h"
#include "chip.h"
#include "comm.h"
enum {
MIDI_BUFSIZE = 64
};
static void usb6fire_midi_out_handler(struct urb *urb)
{
struct midi_runtime *rt = urb->context;
int ret;
unsigned long flags;
spin_lock_irqsave(&rt->out_lock, flags);
if (rt->out) {
ret = snd_rawmidi_transmit(rt->out, rt->out_buffer + 4,
MIDI_BUFSIZE - 4);
if (ret > 0) { /* more data available, send next packet */
rt->out_buffer[1] = ret + 2;
rt->out_buffer[3] = rt->out_serial++;
urb->transfer_buffer_length = ret + 4;
ret = usb_submit_urb(urb, GFP_ATOMIC);
if (ret < 0)
dev_err(&urb->dev->dev,
"midi out urb submit failed: %d\n",
ret);
} else /* no more data to transmit */
rt->out = NULL;
}
spin_unlock_irqrestore(&rt->out_lock, flags);
}
static void usb6fire_midi_in_received(
struct midi_runtime *rt, u8 *data, int length)
{
unsigned long flags;
spin_lock_irqsave(&rt->in_lock, flags);
if (rt->in)
snd_rawmidi_receive(rt->in, data, length);
spin_unlock_irqrestore(&rt->in_lock, flags);
}
static int usb6fire_midi_out_open(struct snd_rawmidi_substream *alsa_sub)
{
return 0;
}
static int usb6fire_midi_out_close(struct snd_rawmidi_substream *alsa_sub)
{
return 0;
}
static void usb6fire_midi_out_trigger(
struct snd_rawmidi_substream *alsa_sub, int up)
{
struct midi_runtime *rt = alsa_sub->rmidi->private_data;
struct urb *urb = &rt->out_urb;
__s8 ret;
unsigned long flags;
spin_lock_irqsave(&rt->out_lock, flags);
if (up) { /* start transfer */
if (rt->out) { /* we are already transmitting so just return */
spin_unlock_irqrestore(&rt->out_lock, flags);
return;
}
ret = snd_rawmidi_transmit(alsa_sub, rt->out_buffer + 4,
MIDI_BUFSIZE - 4);
if (ret > 0) {
rt->out_buffer[1] = ret + 2;
rt->out_buffer[3] = rt->out_serial++;
urb->transfer_buffer_length = ret + 4;
ret = usb_submit_urb(urb, GFP_ATOMIC);
if (ret < 0)
dev_err(&urb->dev->dev,
"midi out urb submit failed: %d\n",
ret);
else
rt->out = alsa_sub;
}
} else if (rt->out == alsa_sub)
rt->out = NULL;
spin_unlock_irqrestore(&rt->out_lock, flags);
}
static void usb6fire_midi_out_drain(struct snd_rawmidi_substream *alsa_sub)
{
struct midi_runtime *rt = alsa_sub->rmidi->private_data;
int retry = 0;
while (rt->out && retry++ < 100)
msleep(10);
}
static int usb6fire_midi_in_open(struct snd_rawmidi_substream *alsa_sub)
{
return 0;
}
static int usb6fire_midi_in_close(struct snd_rawmidi_substream *alsa_sub)
{
return 0;
}
static void usb6fire_midi_in_trigger(
struct snd_rawmidi_substream *alsa_sub, int up)
{
struct midi_runtime *rt = alsa_sub->rmidi->private_data;
unsigned long flags;
spin_lock_irqsave(&rt->in_lock, flags);
if (up)
rt->in = alsa_sub;
else
rt->in = NULL;
spin_unlock_irqrestore(&rt->in_lock, flags);
}
static const struct snd_rawmidi_ops out_ops = {
.open = usb6fire_midi_out_open,
.close = usb6fire_midi_out_close,
.trigger = usb6fire_midi_out_trigger,
.drain = usb6fire_midi_out_drain
};
static const struct snd_rawmidi_ops in_ops = {
.open = usb6fire_midi_in_open,
.close = usb6fire_midi_in_close,
.trigger = usb6fire_midi_in_trigger
};
int usb6fire_midi_init(struct sfire_chip *chip)
{
int ret;
struct midi_runtime *rt = kzalloc(sizeof(struct midi_runtime),
GFP_KERNEL);
struct comm_runtime *comm_rt = chip->comm;
if (!rt)
return -ENOMEM;
rt->out_buffer = kzalloc(MIDI_BUFSIZE, GFP_KERNEL);
if (!rt->out_buffer) {
kfree(rt);
return -ENOMEM;
}
rt->chip = chip;
rt->in_received = usb6fire_midi_in_received;
rt->out_buffer[0] = 0x80; /* 'send midi' command */
rt->out_buffer[1] = 0x00; /* size of data */
rt->out_buffer[2] = 0x00; /* always 0 */
spin_lock_init(&rt->in_lock);
spin_lock_init(&rt->out_lock);
comm_rt->init_urb(comm_rt, &rt->out_urb, rt->out_buffer, rt,
usb6fire_midi_out_handler);
ret = snd_rawmidi_new(chip->card, "6FireUSB", 0, 1, 1, &rt->instance);
if (ret < 0) {
kfree(rt->out_buffer);
kfree(rt);
dev_err(&chip->dev->dev, "unable to create midi.\n");
return ret;
}
rt->instance->private_data = rt;
strcpy(rt->instance->name, "DMX6FireUSB MIDI");
rt->instance->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
SNDRV_RAWMIDI_INFO_INPUT |
SNDRV_RAWMIDI_INFO_DUPLEX;
snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_OUTPUT,
&out_ops);
snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_INPUT,
&in_ops);
chip->midi = rt;
return 0;
}
void usb6fire_midi_abort(struct sfire_chip *chip)
{
struct midi_runtime *rt = chip->midi;
if (rt)
usb_poison_urb(&rt->out_urb);
}
void usb6fire_midi_destroy(struct sfire_chip *chip)
{
struct midi_runtime *rt = chip->midi;
kfree(rt->out_buffer);
kfree(rt);
chip->midi = NULL;
}