Merge tag '5.7-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6
[sfrench/cifs-2.6.git] / sound / firewire / bebob / bebob_hwdep.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * bebob_hwdep.c - a part of driver for BeBoB based devices
4  *
5  * Copyright (c) 2013-2014 Takashi Sakamoto
6  */
7
8 /*
9  * This codes give three functionality.
10  *
11  * 1.get firewire node infomation
12  * 2.get notification about starting/stopping stream
13  * 3.lock/unlock stream
14  */
15
16 #include "bebob.h"
17
18 static long
19 hwdep_read(struct snd_hwdep *hwdep, char __user *buf,  long count,
20            loff_t *offset)
21 {
22         struct snd_bebob *bebob = hwdep->private_data;
23         DEFINE_WAIT(wait);
24         union snd_firewire_event event;
25
26         spin_lock_irq(&bebob->lock);
27
28         while (!bebob->dev_lock_changed) {
29                 prepare_to_wait(&bebob->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
30                 spin_unlock_irq(&bebob->lock);
31                 schedule();
32                 finish_wait(&bebob->hwdep_wait, &wait);
33                 if (signal_pending(current))
34                         return -ERESTARTSYS;
35                 spin_lock_irq(&bebob->lock);
36         }
37
38         memset(&event, 0, sizeof(event));
39         if (bebob->dev_lock_changed) {
40                 event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
41                 event.lock_status.status = (bebob->dev_lock_count > 0);
42                 bebob->dev_lock_changed = false;
43
44                 count = min_t(long, count, sizeof(event.lock_status));
45         }
46
47         spin_unlock_irq(&bebob->lock);
48
49         if (copy_to_user(buf, &event, count))
50                 return -EFAULT;
51
52         return count;
53 }
54
55 static __poll_t
56 hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait)
57 {
58         struct snd_bebob *bebob = hwdep->private_data;
59         __poll_t events;
60
61         poll_wait(file, &bebob->hwdep_wait, wait);
62
63         spin_lock_irq(&bebob->lock);
64         if (bebob->dev_lock_changed)
65                 events = EPOLLIN | EPOLLRDNORM;
66         else
67                 events = 0;
68         spin_unlock_irq(&bebob->lock);
69
70         return events;
71 }
72
73 static int
74 hwdep_get_info(struct snd_bebob *bebob, void __user *arg)
75 {
76         struct fw_device *dev = fw_parent_device(bebob->unit);
77         struct snd_firewire_get_info info;
78
79         memset(&info, 0, sizeof(info));
80         info.type = SNDRV_FIREWIRE_TYPE_BEBOB;
81         info.card = dev->card->index;
82         *(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
83         *(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
84         strlcpy(info.device_name, dev_name(&dev->device),
85                 sizeof(info.device_name));
86
87         if (copy_to_user(arg, &info, sizeof(info)))
88                 return -EFAULT;
89
90         return 0;
91 }
92
93 static int
94 hwdep_lock(struct snd_bebob *bebob)
95 {
96         int err;
97
98         spin_lock_irq(&bebob->lock);
99
100         if (bebob->dev_lock_count == 0) {
101                 bebob->dev_lock_count = -1;
102                 err = 0;
103         } else {
104                 err = -EBUSY;
105         }
106
107         spin_unlock_irq(&bebob->lock);
108
109         return err;
110 }
111
112 static int
113 hwdep_unlock(struct snd_bebob *bebob)
114 {
115         int err;
116
117         spin_lock_irq(&bebob->lock);
118
119         if (bebob->dev_lock_count == -1) {
120                 bebob->dev_lock_count = 0;
121                 err = 0;
122         } else {
123                 err = -EBADFD;
124         }
125
126         spin_unlock_irq(&bebob->lock);
127
128         return err;
129 }
130
131 static int
132 hwdep_release(struct snd_hwdep *hwdep, struct file *file)
133 {
134         struct snd_bebob *bebob = hwdep->private_data;
135
136         spin_lock_irq(&bebob->lock);
137         if (bebob->dev_lock_count == -1)
138                 bebob->dev_lock_count = 0;
139         spin_unlock_irq(&bebob->lock);
140
141         return 0;
142 }
143
144 static int
145 hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
146             unsigned int cmd, unsigned long arg)
147 {
148         struct snd_bebob *bebob = hwdep->private_data;
149
150         switch (cmd) {
151         case SNDRV_FIREWIRE_IOCTL_GET_INFO:
152                 return hwdep_get_info(bebob, (void __user *)arg);
153         case SNDRV_FIREWIRE_IOCTL_LOCK:
154                 return hwdep_lock(bebob);
155         case SNDRV_FIREWIRE_IOCTL_UNLOCK:
156                 return hwdep_unlock(bebob);
157         default:
158                 return -ENOIOCTLCMD;
159         }
160 }
161
162 #ifdef CONFIG_COMPAT
163 static int
164 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
174 int snd_bebob_create_hwdep_device(struct snd_bebob *bebob)
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(bebob->card, "BeBoB", 0, &hwdep);
187         if (err < 0)
188                 goto end;
189         strcpy(hwdep->name, "BeBoB");
190         hwdep->iface = SNDRV_HWDEP_IFACE_FW_BEBOB;
191         hwdep->ops = ops;
192         hwdep->private_data = bebob;
193         hwdep->exclusive = true;
194 end:
195         return err;
196 }
197