1/*
2 * Line6 Linux USB driver - 0.9.1beta
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 <sound/core.h>
15#include <sound/rawmidi.h>
16
17#include "audio.h"
18#include "driver.h"
19#include "midi.h"
20#include "pod.h"
21#include "usbdefs.h"
22
23#define line6_rawmidi_substream_midi(substream) \
24	((struct snd_line6_midi *)((substream)->rmidi->private_data))
25
26static int send_midi_async(struct usb_line6 *line6, unsigned char *data,
27			   int length);
28
29/*
30	Pass data received via USB to MIDI.
31*/
32void line6_midi_receive(struct usb_line6 *line6, unsigned char *data,
33			int length)
34{
35	if (line6->line6midi->substream_receive)
36		snd_rawmidi_receive(line6->line6midi->substream_receive,
37				    data, length);
38}
39
40/*
41	Read data from MIDI buffer and transmit them via USB.
42*/
43static void line6_midi_transmit(struct snd_rawmidi_substream *substream)
44{
45	struct usb_line6 *line6 =
46	    line6_rawmidi_substream_midi(substream)->line6;
47	struct snd_line6_midi *line6midi = line6->line6midi;
48	struct midi_buffer *mb = &line6midi->midibuf_out;
49	unsigned long flags;
50	unsigned char chunk[LINE6_FALLBACK_MAXPACKETSIZE];
51	int req, done;
52
53	spin_lock_irqsave(&line6->line6midi->midi_transmit_lock, flags);
54
55	for (;;) {
56		req = min(line6_midibuf_bytes_free(mb), line6->max_packet_size);
57		done = snd_rawmidi_transmit_peek(substream, chunk, req);
58
59		if (done == 0)
60			break;
61
62		line6_midibuf_write(mb, chunk, done);
63		snd_rawmidi_transmit_ack(substream, done);
64	}
65
66	for (;;) {
67		done = line6_midibuf_read(mb, chunk,
68					  LINE6_FALLBACK_MAXPACKETSIZE);
69
70		if (done == 0)
71			break;
72
73		send_midi_async(line6, chunk, done);
74	}
75
76	spin_unlock_irqrestore(&line6->line6midi->midi_transmit_lock, flags);
77}
78
79/*
80	Notification of completion of MIDI transmission.
81*/
82static void midi_sent(struct urb *urb)
83{
84	unsigned long flags;
85	int status;
86	int num;
87	struct usb_line6 *line6 = (struct usb_line6 *)urb->context;
88
89	status = urb->status;
90	kfree(urb->transfer_buffer);
91	usb_free_urb(urb);
92
93	if (status == -ESHUTDOWN)
94		return;
95
96	spin_lock_irqsave(&line6->line6midi->send_urb_lock, flags);
97	num = --line6->line6midi->num_active_send_urbs;
98
99	if (num == 0) {
100		line6_midi_transmit(line6->line6midi->substream_transmit);
101		num = line6->line6midi->num_active_send_urbs;
102	}
103
104	if (num == 0)
105		wake_up(&line6->line6midi->send_wait);
106
107	spin_unlock_irqrestore(&line6->line6midi->send_urb_lock, flags);
108}
109
110/*
111	Send an asynchronous MIDI message.
112	Assumes that line6->line6midi->send_urb_lock is held
113	(i.e., this function is serialized).
114*/
115static int send_midi_async(struct usb_line6 *line6, unsigned char *data,
116			   int length)
117{
118	struct urb *urb;
119	int retval;
120	unsigned char *transfer_buffer;
121
122	urb = usb_alloc_urb(0, GFP_ATOMIC);
123
124	if (urb == NULL) {
125		dev_err(line6->ifcdev, "Out of memory\n");
126		return -ENOMEM;
127	}
128
129	transfer_buffer = kmemdup(data, length, GFP_ATOMIC);
130
131	if (transfer_buffer == NULL) {
132		usb_free_urb(urb);
133		dev_err(line6->ifcdev, "Out of memory\n");
134		return -ENOMEM;
135	}
136
137	usb_fill_int_urb(urb, line6->usbdev,
138			 usb_sndbulkpipe(line6->usbdev,
139					 line6->ep_control_write),
140			 transfer_buffer, length, midi_sent, line6,
141			 line6->interval);
142	urb->actual_length = 0;
143	retval = usb_submit_urb(urb, GFP_ATOMIC);
144
145	if (retval < 0) {
146		dev_err(line6->ifcdev, "usb_submit_urb failed\n");
147		usb_free_urb(urb);
148		return retval;
149	}
150
151	++line6->line6midi->num_active_send_urbs;
152	return 0;
153}
154
155static int line6_midi_output_open(struct snd_rawmidi_substream *substream)
156{
157	return 0;
158}
159
160static int line6_midi_output_close(struct snd_rawmidi_substream *substream)
161{
162	return 0;
163}
164
165static void line6_midi_output_trigger(struct snd_rawmidi_substream *substream,
166				      int up)
167{
168	unsigned long flags;
169	struct usb_line6 *line6 =
170	    line6_rawmidi_substream_midi(substream)->line6;
171
172	line6->line6midi->substream_transmit = substream;
173	spin_lock_irqsave(&line6->line6midi->send_urb_lock, flags);
174
175	if (line6->line6midi->num_active_send_urbs == 0)
176		line6_midi_transmit(substream);
177
178	spin_unlock_irqrestore(&line6->line6midi->send_urb_lock, flags);
179}
180
181static void line6_midi_output_drain(struct snd_rawmidi_substream *substream)
182{
183	struct usb_line6 *line6 =
184	    line6_rawmidi_substream_midi(substream)->line6;
185	struct snd_line6_midi *midi = line6->line6midi;
186
187	wait_event_interruptible(midi->send_wait,
188				 midi->num_active_send_urbs == 0);
189}
190
191static int line6_midi_input_open(struct snd_rawmidi_substream *substream)
192{
193	return 0;
194}
195
196static int line6_midi_input_close(struct snd_rawmidi_substream *substream)
197{
198	return 0;
199}
200
201static void line6_midi_input_trigger(struct snd_rawmidi_substream *substream,
202				     int up)
203{
204	struct usb_line6 *line6 =
205	    line6_rawmidi_substream_midi(substream)->line6;
206
207	if (up)
208		line6->line6midi->substream_receive = substream;
209	else
210		line6->line6midi->substream_receive = NULL;
211}
212
213static struct snd_rawmidi_ops line6_midi_output_ops = {
214	.open = line6_midi_output_open,
215	.close = line6_midi_output_close,
216	.trigger = line6_midi_output_trigger,
217	.drain = line6_midi_output_drain,
218};
219
220static struct snd_rawmidi_ops line6_midi_input_ops = {
221	.open = line6_midi_input_open,
222	.close = line6_midi_input_close,
223	.trigger = line6_midi_input_trigger,
224};
225
226/*
227	Cleanup the Line6 MIDI device.
228*/
229static void line6_cleanup_midi(struct snd_rawmidi *rmidi)
230{
231}
232
233/* Create a MIDI device */
234static int snd_line6_new_midi(struct snd_line6_midi *line6midi)
235{
236	struct snd_rawmidi *rmidi;
237	int err;
238
239	err = snd_rawmidi_new(line6midi->line6->card, "Line6 MIDI", 0, 1, 1,
240			      &rmidi);
241	if (err < 0)
242		return err;
243
244	rmidi->private_data = line6midi;
245	rmidi->private_free = line6_cleanup_midi;
246	strcpy(rmidi->id, line6midi->line6->properties->id);
247	strcpy(rmidi->name, line6midi->line6->properties->name);
248
249	rmidi->info_flags =
250	    SNDRV_RAWMIDI_INFO_OUTPUT |
251	    SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
252
253	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
254			    &line6_midi_output_ops);
255	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
256			    &line6_midi_input_ops);
257	return 0;
258}
259
260/* MIDI device destructor */
261static int snd_line6_midi_free(struct snd_device *device)
262{
263	struct snd_line6_midi *line6midi = device->device_data;
264
265	line6_midibuf_destroy(&line6midi->midibuf_in);
266	line6_midibuf_destroy(&line6midi->midibuf_out);
267	return 0;
268}
269
270/*
271	Initialize the Line6 MIDI subsystem.
272*/
273int line6_init_midi(struct usb_line6 *line6)
274{
275	static struct snd_device_ops midi_ops = {
276		.dev_free = snd_line6_midi_free,
277	};
278
279	int err;
280	struct snd_line6_midi *line6midi;
281
282	if (!(line6->properties->capabilities & LINE6_BIT_CONTROL)) {
283		/* skip MIDI initialization and report success */
284		return 0;
285	}
286
287	line6midi = kzalloc(sizeof(struct snd_line6_midi), GFP_KERNEL);
288
289	if (line6midi == NULL)
290		return -ENOMEM;
291
292	err = line6_midibuf_init(&line6midi->midibuf_in, MIDI_BUFFER_SIZE, 0);
293	if (err < 0) {
294		kfree(line6midi);
295		return err;
296	}
297
298	err = line6_midibuf_init(&line6midi->midibuf_out, MIDI_BUFFER_SIZE, 1);
299	if (err < 0) {
300		kfree(line6midi->midibuf_in.buf);
301		kfree(line6midi);
302		return err;
303	}
304
305	line6midi->line6 = line6;
306	line6->line6midi = line6midi;
307
308	err = snd_device_new(line6->card, SNDRV_DEV_RAWMIDI, line6midi,
309			     &midi_ops);
310	if (err < 0)
311		return err;
312
313	err = snd_line6_new_midi(line6midi);
314	if (err < 0)
315		return err;
316
317	init_waitqueue_head(&line6midi->send_wait);
318	spin_lock_init(&line6midi->send_urb_lock);
319	spin_lock_init(&line6midi->midi_transmit_lock);
320	return 0;
321}
322