1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * motu-hwdep.c - a part of driver for MOTU FireWire series
4 *
5 * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
6 */
7
8 /*
9 * This codes have five functionalities.
10 *
11 * 1.get information about firewire node
12 * 2.get notification about starting/stopping stream
13 * 3.lock/unlock streaming
14 *
15 */
16
17 #include "motu.h"
18
hwdep_read(struct snd_hwdep * hwdep,char __user * buf,long count,loff_t * offset)19 static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
20 loff_t *offset)
21 {
22 struct snd_motu *motu = hwdep->private_data;
23 DEFINE_WAIT(wait);
24 union snd_firewire_event event;
25
26 spin_lock_irq(&motu->lock);
27
28 while (!motu->dev_lock_changed && motu->msg == 0) {
29 prepare_to_wait(&motu->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
30 spin_unlock_irq(&motu->lock);
31 schedule();
32 finish_wait(&motu->hwdep_wait, &wait);
33 if (signal_pending(current))
34 return -ERESTARTSYS;
35 spin_lock_irq(&motu->lock);
36 }
37
38 memset(&event, 0, sizeof(event));
39 if (motu->dev_lock_changed) {
40 event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
41 event.lock_status.status = (motu->dev_lock_count > 0);
42 motu->dev_lock_changed = false;
43
44 count = min_t(long, count, sizeof(event.lock_status));
45 } else {
46 event.motu_notification.type = SNDRV_FIREWIRE_EVENT_MOTU_NOTIFICATION;
47 event.motu_notification.message = motu->msg;
48 motu->msg = 0;
49
50 count = min_t(long, count, sizeof(event.motu_notification));
51 }
52
53 spin_unlock_irq(&motu->lock);
54
55 if (copy_to_user(buf, &event, count))
56 return -EFAULT;
57
58 return count;
59 }
60
hwdep_poll(struct snd_hwdep * hwdep,struct file * file,poll_table * wait)61 static __poll_t hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
62 poll_table *wait)
63 {
64 struct snd_motu *motu = hwdep->private_data;
65 __poll_t events;
66
67 poll_wait(file, &motu->hwdep_wait, wait);
68
69 spin_lock_irq(&motu->lock);
70 if (motu->dev_lock_changed || motu->msg)
71 events = EPOLLIN | EPOLLRDNORM;
72 else
73 events = 0;
74 spin_unlock_irq(&motu->lock);
75
76 return events | EPOLLOUT;
77 }
78
hwdep_get_info(struct snd_motu * motu,void __user * arg)79 static int hwdep_get_info(struct snd_motu *motu, void __user *arg)
80 {
81 struct fw_device *dev = fw_parent_device(motu->unit);
82 struct snd_firewire_get_info info;
83
84 memset(&info, 0, sizeof(info));
85 info.type = SNDRV_FIREWIRE_TYPE_MOTU;
86 info.card = dev->card->index;
87 *(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
88 *(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
89 strscpy(info.device_name, dev_name(&dev->device),
90 sizeof(info.device_name));
91
92 if (copy_to_user(arg, &info, sizeof(info)))
93 return -EFAULT;
94
95 return 0;
96 }
97
hwdep_lock(struct snd_motu * motu)98 static int hwdep_lock(struct snd_motu *motu)
99 {
100 int err;
101
102 spin_lock_irq(&motu->lock);
103
104 if (motu->dev_lock_count == 0) {
105 motu->dev_lock_count = -1;
106 err = 0;
107 } else {
108 err = -EBUSY;
109 }
110
111 spin_unlock_irq(&motu->lock);
112
113 return err;
114 }
115
hwdep_unlock(struct snd_motu * motu)116 static int hwdep_unlock(struct snd_motu *motu)
117 {
118 int err;
119
120 spin_lock_irq(&motu->lock);
121
122 if (motu->dev_lock_count == -1) {
123 motu->dev_lock_count = 0;
124 err = 0;
125 } else {
126 err = -EBADFD;
127 }
128
129 spin_unlock_irq(&motu->lock);
130
131 return err;
132 }
133
hwdep_release(struct snd_hwdep * hwdep,struct file * file)134 static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
135 {
136 struct snd_motu *motu = hwdep->private_data;
137
138 spin_lock_irq(&motu->lock);
139 if (motu->dev_lock_count == -1)
140 motu->dev_lock_count = 0;
141 spin_unlock_irq(&motu->lock);
142
143 return 0;
144 }
145
hwdep_ioctl(struct snd_hwdep * hwdep,struct file * file,unsigned int cmd,unsigned long arg)146 static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
147 unsigned int cmd, unsigned long arg)
148 {
149 struct snd_motu *motu = hwdep->private_data;
150
151 switch (cmd) {
152 case SNDRV_FIREWIRE_IOCTL_GET_INFO:
153 return hwdep_get_info(motu, (void __user *)arg);
154 case SNDRV_FIREWIRE_IOCTL_LOCK:
155 return hwdep_lock(motu);
156 case SNDRV_FIREWIRE_IOCTL_UNLOCK:
157 return hwdep_unlock(motu);
158 default:
159 return -ENOIOCTLCMD;
160 }
161 }
162
163 #ifdef CONFIG_COMPAT
hwdep_compat_ioctl(struct snd_hwdep * hwdep,struct file * file,unsigned int cmd,unsigned long arg)164 static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
165 unsigned int cmd, unsigned long arg)
166 {
167 return hwdep_ioctl(hwdep, file, cmd,
168 (unsigned long)compat_ptr(arg));
169 }
170 #else
171 #define hwdep_compat_ioctl NULL
172 #endif
173
snd_motu_create_hwdep_device(struct snd_motu * motu)174 int snd_motu_create_hwdep_device(struct snd_motu *motu)
175 {
176 static const struct snd_hwdep_ops ops = {
177 .read = hwdep_read,
178 .release = hwdep_release,
179 .poll = hwdep_poll,
180 .ioctl = hwdep_ioctl,
181 .ioctl_compat = hwdep_compat_ioctl,
182 };
183 struct snd_hwdep *hwdep;
184 int err;
185
186 err = snd_hwdep_new(motu->card, motu->card->driver, 0, &hwdep);
187 if (err < 0)
188 return err;
189
190 strcpy(hwdep->name, "MOTU");
191 hwdep->iface = SNDRV_HWDEP_IFACE_FW_MOTU;
192 hwdep->ops = ops;
193 hwdep->private_data = motu;
194 hwdep->exclusive = true;
195
196 return 0;
197 }
198