xref: /openbmc/linux/sound/usb/6fire/midi.c (revision f35e839a)
1 /*
2  * Linux driver for TerraTec DMX 6Fire USB
3  *
4  * Rawmidi driver
5  *
6  * Author:	Torsten Schenk <torsten.schenk@zoho.com>
7  * Created:	Jan 01, 2011
8  * Copyright:	(C) Torsten Schenk
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  */
15 
16 #include <sound/rawmidi.h>
17 
18 #include "midi.h"
19 #include "chip.h"
20 #include "comm.h"
21 
22 static void usb6fire_midi_out_handler(struct urb *urb)
23 {
24 	struct midi_runtime *rt = urb->context;
25 	int ret;
26 	unsigned long flags;
27 
28 	spin_lock_irqsave(&rt->out_lock, flags);
29 
30 	if (rt->out) {
31 		ret = snd_rawmidi_transmit(rt->out, rt->out_buffer + 4,
32 				MIDI_BUFSIZE - 4);
33 		if (ret > 0) { /* more data available, send next packet */
34 			rt->out_buffer[1] = ret + 2;
35 			rt->out_buffer[3] = rt->out_serial++;
36 			urb->transfer_buffer_length = ret + 4;
37 
38 			ret = usb_submit_urb(urb, GFP_ATOMIC);
39 			if (ret < 0)
40 				snd_printk(KERN_ERR PREFIX "midi out urb "
41 						"submit failed: %d\n", ret);
42 		} else /* no more data to transmit */
43 			rt->out = NULL;
44 	}
45 	spin_unlock_irqrestore(&rt->out_lock, flags);
46 }
47 
48 static void usb6fire_midi_in_received(
49 		struct midi_runtime *rt, u8 *data, int length)
50 {
51 	unsigned long flags;
52 
53 	spin_lock_irqsave(&rt->in_lock, flags);
54 	if (rt->in)
55 		snd_rawmidi_receive(rt->in, data, length);
56 	spin_unlock_irqrestore(&rt->in_lock, flags);
57 }
58 
59 static int usb6fire_midi_out_open(struct snd_rawmidi_substream *alsa_sub)
60 {
61 	return 0;
62 }
63 
64 static int usb6fire_midi_out_close(struct snd_rawmidi_substream *alsa_sub)
65 {
66 	return 0;
67 }
68 
69 static void usb6fire_midi_out_trigger(
70 		struct snd_rawmidi_substream *alsa_sub, int up)
71 {
72 	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
73 	struct urb *urb = &rt->out_urb;
74 	__s8 ret;
75 	unsigned long flags;
76 
77 	spin_lock_irqsave(&rt->out_lock, flags);
78 	if (up) { /* start transfer */
79 		if (rt->out) { /* we are already transmitting so just return */
80 			spin_unlock_irqrestore(&rt->out_lock, flags);
81 			return;
82 		}
83 
84 		ret = snd_rawmidi_transmit(alsa_sub, rt->out_buffer + 4,
85 				MIDI_BUFSIZE - 4);
86 		if (ret > 0) {
87 			rt->out_buffer[1] = ret + 2;
88 			rt->out_buffer[3] = rt->out_serial++;
89 			urb->transfer_buffer_length = ret + 4;
90 
91 			ret = usb_submit_urb(urb, GFP_ATOMIC);
92 			if (ret < 0)
93 				snd_printk(KERN_ERR PREFIX "midi out urb "
94 						"submit failed: %d\n", ret);
95 			else
96 				rt->out = alsa_sub;
97 		}
98 	} else if (rt->out == alsa_sub)
99 		rt->out = NULL;
100 	spin_unlock_irqrestore(&rt->out_lock, flags);
101 }
102 
103 static void usb6fire_midi_out_drain(struct snd_rawmidi_substream *alsa_sub)
104 {
105 	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
106 	int retry = 0;
107 
108 	while (rt->out && retry++ < 100)
109 		msleep(10);
110 }
111 
112 static int usb6fire_midi_in_open(struct snd_rawmidi_substream *alsa_sub)
113 {
114 	return 0;
115 }
116 
117 static int usb6fire_midi_in_close(struct snd_rawmidi_substream *alsa_sub)
118 {
119 	return 0;
120 }
121 
122 static void usb6fire_midi_in_trigger(
123 		struct snd_rawmidi_substream *alsa_sub, int up)
124 {
125 	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
126 	unsigned long flags;
127 
128 	spin_lock_irqsave(&rt->in_lock, flags);
129 	if (up)
130 		rt->in = alsa_sub;
131 	else
132 		rt->in = NULL;
133 	spin_unlock_irqrestore(&rt->in_lock, flags);
134 }
135 
136 static struct snd_rawmidi_ops out_ops = {
137 	.open = usb6fire_midi_out_open,
138 	.close = usb6fire_midi_out_close,
139 	.trigger = usb6fire_midi_out_trigger,
140 	.drain = usb6fire_midi_out_drain
141 };
142 
143 static struct snd_rawmidi_ops in_ops = {
144 	.open = usb6fire_midi_in_open,
145 	.close = usb6fire_midi_in_close,
146 	.trigger = usb6fire_midi_in_trigger
147 };
148 
149 int usb6fire_midi_init(struct sfire_chip *chip)
150 {
151 	int ret;
152 	struct midi_runtime *rt = kzalloc(sizeof(struct midi_runtime),
153 			GFP_KERNEL);
154 	struct comm_runtime *comm_rt = chip->comm;
155 
156 	if (!rt)
157 		return -ENOMEM;
158 
159 	rt->chip = chip;
160 	rt->in_received = usb6fire_midi_in_received;
161 	rt->out_buffer[0] = 0x80; /* 'send midi' command */
162 	rt->out_buffer[1] = 0x00; /* size of data */
163 	rt->out_buffer[2] = 0x00; /* always 0 */
164 	spin_lock_init(&rt->in_lock);
165 	spin_lock_init(&rt->out_lock);
166 
167 	comm_rt->init_urb(comm_rt, &rt->out_urb, rt->out_buffer, rt,
168 			usb6fire_midi_out_handler);
169 
170 	ret = snd_rawmidi_new(chip->card, "6FireUSB", 0, 1, 1, &rt->instance);
171 	if (ret < 0) {
172 		kfree(rt);
173 		snd_printk(KERN_ERR PREFIX "unable to create midi.\n");
174 		return ret;
175 	}
176 	rt->instance->private_data = rt;
177 	strcpy(rt->instance->name, "DMX6FireUSB MIDI");
178 	rt->instance->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
179 			SNDRV_RAWMIDI_INFO_INPUT |
180 			SNDRV_RAWMIDI_INFO_DUPLEX;
181 	snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_OUTPUT,
182 			&out_ops);
183 	snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_INPUT,
184 			&in_ops);
185 
186 	chip->midi = rt;
187 	return 0;
188 }
189 
190 void usb6fire_midi_abort(struct sfire_chip *chip)
191 {
192 	struct midi_runtime *rt = chip->midi;
193 
194 	if (rt)
195 		usb_poison_urb(&rt->out_urb);
196 }
197 
198 void usb6fire_midi_destroy(struct sfire_chip *chip)
199 {
200 	kfree(chip->midi);
201 	chip->midi = NULL;
202 }
203