xref: /openbmc/linux/sound/usb/6fire/midi.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Linux driver for TerraTec DMX 6Fire USB
4  *
5  * Rawmidi driver
6  *
7  * Author:	Torsten Schenk <torsten.schenk@zoho.com>
8  * Created:	Jan 01, 2011
9  * Copyright:	(C) Torsten Schenk
10  */
11 
12 #include <sound/rawmidi.h>
13 
14 #include "midi.h"
15 #include "chip.h"
16 #include "comm.h"
17 
18 enum {
19 	MIDI_BUFSIZE = 64
20 };
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 				dev_err(&urb->dev->dev,
41 					"midi out urb submit failed: %d\n",
42 					ret);
43 		} else /* no more data to transmit */
44 			rt->out = NULL;
45 	}
46 	spin_unlock_irqrestore(&rt->out_lock, flags);
47 }
48 
49 static void usb6fire_midi_in_received(
50 		struct midi_runtime *rt, u8 *data, int length)
51 {
52 	unsigned long flags;
53 
54 	spin_lock_irqsave(&rt->in_lock, flags);
55 	if (rt->in)
56 		snd_rawmidi_receive(rt->in, data, length);
57 	spin_unlock_irqrestore(&rt->in_lock, flags);
58 }
59 
60 static int usb6fire_midi_out_open(struct snd_rawmidi_substream *alsa_sub)
61 {
62 	return 0;
63 }
64 
65 static int usb6fire_midi_out_close(struct snd_rawmidi_substream *alsa_sub)
66 {
67 	return 0;
68 }
69 
70 static void usb6fire_midi_out_trigger(
71 		struct snd_rawmidi_substream *alsa_sub, int up)
72 {
73 	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
74 	struct urb *urb = &rt->out_urb;
75 	__s8 ret;
76 	unsigned long flags;
77 
78 	spin_lock_irqsave(&rt->out_lock, flags);
79 	if (up) { /* start transfer */
80 		if (rt->out) { /* we are already transmitting so just return */
81 			spin_unlock_irqrestore(&rt->out_lock, flags);
82 			return;
83 		}
84 
85 		ret = snd_rawmidi_transmit(alsa_sub, rt->out_buffer + 4,
86 				MIDI_BUFSIZE - 4);
87 		if (ret > 0) {
88 			rt->out_buffer[1] = ret + 2;
89 			rt->out_buffer[3] = rt->out_serial++;
90 			urb->transfer_buffer_length = ret + 4;
91 
92 			ret = usb_submit_urb(urb, GFP_ATOMIC);
93 			if (ret < 0)
94 				dev_err(&urb->dev->dev,
95 					"midi out urb submit failed: %d\n",
96 					ret);
97 			else
98 				rt->out = alsa_sub;
99 		}
100 	} else if (rt->out == alsa_sub)
101 		rt->out = NULL;
102 	spin_unlock_irqrestore(&rt->out_lock, flags);
103 }
104 
105 static void usb6fire_midi_out_drain(struct snd_rawmidi_substream *alsa_sub)
106 {
107 	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
108 	int retry = 0;
109 
110 	while (rt->out && retry++ < 100)
111 		msleep(10);
112 }
113 
114 static int usb6fire_midi_in_open(struct snd_rawmidi_substream *alsa_sub)
115 {
116 	return 0;
117 }
118 
119 static int usb6fire_midi_in_close(struct snd_rawmidi_substream *alsa_sub)
120 {
121 	return 0;
122 }
123 
124 static void usb6fire_midi_in_trigger(
125 		struct snd_rawmidi_substream *alsa_sub, int up)
126 {
127 	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
128 	unsigned long flags;
129 
130 	spin_lock_irqsave(&rt->in_lock, flags);
131 	if (up)
132 		rt->in = alsa_sub;
133 	else
134 		rt->in = NULL;
135 	spin_unlock_irqrestore(&rt->in_lock, flags);
136 }
137 
138 static const struct snd_rawmidi_ops out_ops = {
139 	.open = usb6fire_midi_out_open,
140 	.close = usb6fire_midi_out_close,
141 	.trigger = usb6fire_midi_out_trigger,
142 	.drain = usb6fire_midi_out_drain
143 };
144 
145 static const struct snd_rawmidi_ops in_ops = {
146 	.open = usb6fire_midi_in_open,
147 	.close = usb6fire_midi_in_close,
148 	.trigger = usb6fire_midi_in_trigger
149 };
150 
151 int usb6fire_midi_init(struct sfire_chip *chip)
152 {
153 	int ret;
154 	struct midi_runtime *rt = kzalloc(sizeof(struct midi_runtime),
155 			GFP_KERNEL);
156 	struct comm_runtime *comm_rt = chip->comm;
157 
158 	if (!rt)
159 		return -ENOMEM;
160 
161 	rt->out_buffer = kzalloc(MIDI_BUFSIZE, GFP_KERNEL);
162 	if (!rt->out_buffer) {
163 		kfree(rt);
164 		return -ENOMEM;
165 	}
166 
167 	rt->chip = chip;
168 	rt->in_received = usb6fire_midi_in_received;
169 	rt->out_buffer[0] = 0x80; /* 'send midi' command */
170 	rt->out_buffer[1] = 0x00; /* size of data */
171 	rt->out_buffer[2] = 0x00; /* always 0 */
172 	spin_lock_init(&rt->in_lock);
173 	spin_lock_init(&rt->out_lock);
174 
175 	comm_rt->init_urb(comm_rt, &rt->out_urb, rt->out_buffer, rt,
176 			usb6fire_midi_out_handler);
177 
178 	ret = snd_rawmidi_new(chip->card, "6FireUSB", 0, 1, 1, &rt->instance);
179 	if (ret < 0) {
180 		kfree(rt->out_buffer);
181 		kfree(rt);
182 		dev_err(&chip->dev->dev, "unable to create midi.\n");
183 		return ret;
184 	}
185 	rt->instance->private_data = rt;
186 	strcpy(rt->instance->name, "DMX6FireUSB MIDI");
187 	rt->instance->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
188 			SNDRV_RAWMIDI_INFO_INPUT |
189 			SNDRV_RAWMIDI_INFO_DUPLEX;
190 	snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_OUTPUT,
191 			&out_ops);
192 	snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_INPUT,
193 			&in_ops);
194 
195 	chip->midi = rt;
196 	return 0;
197 }
198 
199 void usb6fire_midi_abort(struct sfire_chip *chip)
200 {
201 	struct midi_runtime *rt = chip->midi;
202 
203 	if (rt)
204 		usb_poison_urb(&rt->out_urb);
205 }
206 
207 void usb6fire_midi_destroy(struct sfire_chip *chip)
208 {
209 	struct midi_runtime *rt = chip->midi;
210 
211 	kfree(rt->out_buffer);
212 	kfree(rt);
213 	chip->midi = NULL;
214 }
215