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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /sound/usb/line6/midi.c
Initial import
Diffstat (limited to 'sound/usb/line6/midi.c')
-rw-r--r--sound/usb/line6/midi.c292
1 files changed, 292 insertions, 0 deletions
diff --git a/sound/usb/line6/midi.c b/sound/usb/line6/midi.c
new file mode 100644
index 000000000..cebea9b7f
--- /dev/null
+++ b/sound/usb/line6/midi.c
@@ -0,0 +1,292 @@
+/*
+ * 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"
+
+#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);