1/*
2 * digi00x-hwdep.c - a part of driver for Digidesign Digi 002/003 family
3 *
4 * Copyright (c) 2014-2015 Takashi Sakamoto
5 *
6 * Licensed under the terms of the GNU General Public License, version 2.
7 */
8
9/*
10 * This codes give three functionality.
11 *
12 * 1.get firewire node information
13 * 2.get notification about starting/stopping stream
14 * 3.lock/unlock stream
15 * 4.get asynchronous messaging
16 */
17
18#include "digi00x.h"
19
20static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf,  long count,
21		       loff_t *offset)
22{
23	struct snd_dg00x *dg00x = hwdep->private_data;
24	DEFINE_WAIT(wait);
25	union snd_firewire_event event;
26
27	spin_lock_irq(&dg00x->lock);
28
29	while (!dg00x->dev_lock_changed && dg00x->msg == 0) {
30		prepare_to_wait(&dg00x->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
31		spin_unlock_irq(&dg00x->lock);
32		schedule();
33		finish_wait(&dg00x->hwdep_wait, &wait);
34		if (signal_pending(current))
35			return -ERESTARTSYS;
36		spin_lock_irq(&dg00x->lock);
37	}
38
39	memset(&event, 0, sizeof(event));
40	if (dg00x->dev_lock_changed) {
41		event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
42		event.lock_status.status = (dg00x->dev_lock_count > 0);
43		dg00x->dev_lock_changed = false;
44
45		count = min_t(long, count, sizeof(event.lock_status));
46	} else {
47		event.digi00x_message.type =
48					SNDRV_FIREWIRE_EVENT_DIGI00X_MESSAGE;
49		event.digi00x_message.message = dg00x->msg;
50		dg00x->msg = 0;
51
52		count = min_t(long, count, sizeof(event.digi00x_message));
53	}
54
55	spin_unlock_irq(&dg00x->lock);
56
57	if (copy_to_user(buf, &event, count))
58		return -EFAULT;
59
60	return count;
61}
62
63static unsigned int hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
64			       poll_table *wait)
65{
66	struct snd_dg00x *dg00x = hwdep->private_data;
67	unsigned int events;
68
69	poll_wait(file, &dg00x->hwdep_wait, wait);
70
71	spin_lock_irq(&dg00x->lock);
72	if (dg00x->dev_lock_changed || dg00x->msg)
73		events = POLLIN | POLLRDNORM;
74	else
75		events = 0;
76	spin_unlock_irq(&dg00x->lock);
77
78	return events;
79}
80
81static int hwdep_get_info(struct snd_dg00x *dg00x, void __user *arg)
82{
83	struct fw_device *dev = fw_parent_device(dg00x->unit);
84	struct snd_firewire_get_info info;
85
86	memset(&info, 0, sizeof(info));
87	info.type = SNDRV_FIREWIRE_TYPE_DIGI00X;
88	info.card = dev->card->index;
89	*(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
90	*(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
91	strlcpy(info.device_name, dev_name(&dev->device),
92		sizeof(info.device_name));
93
94	if (copy_to_user(arg, &info, sizeof(info)))
95		return -EFAULT;
96
97	return 0;
98}
99
100static int hwdep_lock(struct snd_dg00x *dg00x)
101{
102	int err;
103
104	spin_lock_irq(&dg00x->lock);
105
106	if (dg00x->dev_lock_count == 0) {
107		dg00x->dev_lock_count = -1;
108		err = 0;
109	} else {
110		err = -EBUSY;
111	}
112
113	spin_unlock_irq(&dg00x->lock);
114
115	return err;
116}
117
118static int hwdep_unlock(struct snd_dg00x *dg00x)
119{
120	int err;
121
122	spin_lock_irq(&dg00x->lock);
123
124	if (dg00x->dev_lock_count == -1) {
125		dg00x->dev_lock_count = 0;
126		err = 0;
127	} else {
128		err = -EBADFD;
129	}
130
131	spin_unlock_irq(&dg00x->lock);
132
133	return err;
134}
135
136static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
137{
138	struct snd_dg00x *dg00x = hwdep->private_data;
139
140	spin_lock_irq(&dg00x->lock);
141	if (dg00x->dev_lock_count == -1)
142		dg00x->dev_lock_count = 0;
143	spin_unlock_irq(&dg00x->lock);
144
145	return 0;
146}
147
148static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
149	    unsigned int cmd, unsigned long arg)
150{
151	struct snd_dg00x *dg00x = hwdep->private_data;
152
153	switch (cmd) {
154	case SNDRV_FIREWIRE_IOCTL_GET_INFO:
155		return hwdep_get_info(dg00x, (void __user *)arg);
156	case SNDRV_FIREWIRE_IOCTL_LOCK:
157		return hwdep_lock(dg00x);
158	case SNDRV_FIREWIRE_IOCTL_UNLOCK:
159		return hwdep_unlock(dg00x);
160	default:
161		return -ENOIOCTLCMD;
162	}
163}
164
165#ifdef CONFIG_COMPAT
166static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
167			      unsigned int cmd, unsigned long arg)
168{
169	return hwdep_ioctl(hwdep, file, cmd,
170			   (unsigned long)compat_ptr(arg));
171}
172#else
173#define hwdep_compat_ioctl NULL
174#endif
175
176static const struct snd_hwdep_ops hwdep_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
184int snd_dg00x_create_hwdep_device(struct snd_dg00x *dg00x)
185{
186	struct snd_hwdep *hwdep;
187	int err;
188
189	err = snd_hwdep_new(dg00x->card, "Digi00x", 0, &hwdep);
190	if (err < 0)
191		return err;
192
193	strcpy(hwdep->name, "Digi00x");
194	hwdep->iface = SNDRV_HWDEP_IFACE_FW_DIGI00X;
195	hwdep->ops = hwdep_ops;
196	hwdep->private_data = dg00x;
197	hwdep->exclusive = true;
198
199	return err;
200}
201