xref: /linux/sound/firewire/motu/motu-hwdep.c (revision c1ead4b4dfe0f643cfc66571ca7d2fa332eddd35)
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 
has_dsp_event(struct snd_motu * motu)19 static bool has_dsp_event(struct snd_motu *motu)
20 {
21 	if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP)
22 		return (snd_motu_register_dsp_message_parser_count_event(motu) > 0);
23 	else
24 		return false;
25 }
26 
hwdep_read(struct snd_hwdep * hwdep,char __user * buf,long count,loff_t * offset)27 static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
28 		       loff_t *offset)
29 {
30 	struct snd_motu *motu = hwdep->private_data;
31 	DEFINE_WAIT(wait);
32 	union snd_firewire_event event;
33 
34 	spin_lock_irq(&motu->lock);
35 
36 	while (!motu->dev_lock_changed && motu->msg == 0 && !has_dsp_event(motu)) {
37 		prepare_to_wait(&motu->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
38 		spin_unlock_irq(&motu->lock);
39 		schedule();
40 		finish_wait(&motu->hwdep_wait, &wait);
41 		if (signal_pending(current))
42 			return -ERESTARTSYS;
43 		spin_lock_irq(&motu->lock);
44 	}
45 
46 	memset(&event, 0, sizeof(event));
47 	if (motu->dev_lock_changed) {
48 		event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
49 		event.lock_status.status = (motu->dev_lock_count > 0);
50 		motu->dev_lock_changed = false;
51 		spin_unlock_irq(&motu->lock);
52 
53 		count = min_t(long, count, sizeof(event));
54 		if (copy_to_user(buf, &event, count))
55 			return -EFAULT;
56 	} else if (motu->msg > 0) {
57 		event.motu_notification.type = SNDRV_FIREWIRE_EVENT_MOTU_NOTIFICATION;
58 		event.motu_notification.message = motu->msg;
59 		motu->msg = 0;
60 		spin_unlock_irq(&motu->lock);
61 
62 		count = min_t(long, count, sizeof(event));
63 		if (copy_to_user(buf, &event, count))
64 			return -EFAULT;
65 	} else if (has_dsp_event(motu)) {
66 		size_t consumed = 0;
67 		u32 __user *ptr;
68 		u32 ev;
69 
70 		spin_unlock_irq(&motu->lock);
71 
72 		// Header is filled later.
73 		consumed += sizeof(event.motu_register_dsp_change);
74 
75 		while (consumed < count &&
76 		       snd_motu_register_dsp_message_parser_copy_event(motu, &ev)) {
77 			ptr = (u32 __user *)(buf + consumed);
78 			if (put_user(ev, ptr))
79 				return -EFAULT;
80 			consumed += sizeof(ev);
81 		}
82 
83 		event.motu_register_dsp_change.type = SNDRV_FIREWIRE_EVENT_MOTU_REGISTER_DSP_CHANGE;
84 		event.motu_register_dsp_change.count =
85 			(consumed - sizeof(event.motu_register_dsp_change)) / 4;
86 		if (copy_to_user(buf, &event, sizeof(event.motu_register_dsp_change)))
87 			return -EFAULT;
88 
89 		count = consumed;
90 	} else {
91 		spin_unlock_irq(&motu->lock);
92 
93 		count = 0;
94 	}
95 
96 	return count;
97 }
98 
hwdep_poll(struct snd_hwdep * hwdep,struct file * file,poll_table * wait)99 static __poll_t hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
100 			       poll_table *wait)
101 {
102 	struct snd_motu *motu = hwdep->private_data;
103 
104 	poll_wait(file, &motu->hwdep_wait, wait);
105 
106 	guard(spinlock_irq)(&motu->lock);
107 	if (motu->dev_lock_changed || motu->msg || has_dsp_event(motu))
108 		return EPOLLIN | EPOLLRDNORM;
109 	else
110 		return 0;
111 }
112 
hwdep_get_info(struct snd_motu * motu,void __user * arg)113 static int hwdep_get_info(struct snd_motu *motu, void __user *arg)
114 {
115 	struct fw_device *dev = fw_parent_device(motu->unit);
116 	struct snd_firewire_get_info info;
117 
118 	memset(&info, 0, sizeof(info));
119 	info.type = SNDRV_FIREWIRE_TYPE_MOTU;
120 	info.card = dev->card->index;
121 	*(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
122 	*(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
123 	strscpy(info.device_name, dev_name(&dev->device),
124 		sizeof(info.device_name));
125 
126 	if (copy_to_user(arg, &info, sizeof(info)))
127 		return -EFAULT;
128 
129 	return 0;
130 }
131 
hwdep_lock(struct snd_motu * motu)132 static int hwdep_lock(struct snd_motu *motu)
133 {
134 	guard(spinlock_irq)(&motu->lock);
135 
136 	if (motu->dev_lock_count == 0) {
137 		motu->dev_lock_count = -1;
138 		return 0;
139 	} else {
140 		return -EBUSY;
141 	}
142 }
143 
hwdep_unlock(struct snd_motu * motu)144 static int hwdep_unlock(struct snd_motu *motu)
145 {
146 	guard(spinlock_irq)(&motu->lock);
147 
148 	if (motu->dev_lock_count == -1) {
149 		motu->dev_lock_count = 0;
150 		return 0;
151 	} else {
152 		return -EBADFD;
153 	}
154 }
155 
hwdep_release(struct snd_hwdep * hwdep,struct file * file)156 static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
157 {
158 	struct snd_motu *motu = hwdep->private_data;
159 
160 	guard(spinlock_irq)(&motu->lock);
161 	if (motu->dev_lock_count == -1)
162 		motu->dev_lock_count = 0;
163 
164 	return 0;
165 }
166 
hwdep_ioctl(struct snd_hwdep * hwdep,struct file * file,unsigned int cmd,unsigned long arg)167 static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
168 	    unsigned int cmd, unsigned long arg)
169 {
170 	struct snd_motu *motu = hwdep->private_data;
171 
172 	switch (cmd) {
173 	case SNDRV_FIREWIRE_IOCTL_GET_INFO:
174 		return hwdep_get_info(motu, (void __user *)arg);
175 	case SNDRV_FIREWIRE_IOCTL_LOCK:
176 		return hwdep_lock(motu);
177 	case SNDRV_FIREWIRE_IOCTL_UNLOCK:
178 		return hwdep_unlock(motu);
179 	case SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_METER:
180 	{
181 		struct snd_firewire_motu_register_dsp_meter *meter;
182 		int err;
183 
184 		if (!(motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP))
185 			return -ENXIO;
186 
187 		meter = kzalloc(sizeof(*meter), GFP_KERNEL);
188 		if (!meter)
189 			return -ENOMEM;
190 
191 		snd_motu_register_dsp_message_parser_copy_meter(motu, meter);
192 
193 		err = copy_to_user((void __user *)arg, meter, sizeof(*meter));
194 		kfree(meter);
195 
196 		if (err)
197 			return -EFAULT;
198 
199 		return 0;
200 	}
201 	case SNDRV_FIREWIRE_IOCTL_MOTU_COMMAND_DSP_METER:
202 	{
203 		struct snd_firewire_motu_command_dsp_meter *meter;
204 		int err;
205 
206 		if (!(motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP))
207 			return -ENXIO;
208 
209 		meter = kzalloc(sizeof(*meter), GFP_KERNEL);
210 		if (!meter)
211 			return -ENOMEM;
212 
213 		snd_motu_command_dsp_message_parser_copy_meter(motu, meter);
214 
215 		err = copy_to_user((void __user *)arg, meter, sizeof(*meter));
216 		kfree(meter);
217 
218 		if (err)
219 			return -EFAULT;
220 
221 		return 0;
222 	}
223 	case SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_PARAMETER:
224 	{
225 		struct snd_firewire_motu_register_dsp_parameter *param;
226 		int err;
227 
228 		if (!(motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP))
229 			return -ENXIO;
230 
231 		param = kzalloc(sizeof(*param), GFP_KERNEL);
232 		if (!param)
233 			return -ENOMEM;
234 
235 		snd_motu_register_dsp_message_parser_copy_parameter(motu, param);
236 
237 		err = copy_to_user((void __user *)arg, param, sizeof(*param));
238 		kfree(param);
239 		if (err)
240 			return -EFAULT;
241 
242 		return 0;
243 	}
244 	default:
245 		return -ENOIOCTLCMD;
246 	}
247 }
248 
249 #ifdef CONFIG_COMPAT
hwdep_compat_ioctl(struct snd_hwdep * hwdep,struct file * file,unsigned int cmd,unsigned long arg)250 static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
251 			      unsigned int cmd, unsigned long arg)
252 {
253 	return hwdep_ioctl(hwdep, file, cmd,
254 			   (unsigned long)compat_ptr(arg));
255 }
256 #else
257 #define hwdep_compat_ioctl NULL
258 #endif
259 
snd_motu_create_hwdep_device(struct snd_motu * motu)260 int snd_motu_create_hwdep_device(struct snd_motu *motu)
261 {
262 	static const struct snd_hwdep_ops ops = {
263 		.read		= hwdep_read,
264 		.release	= hwdep_release,
265 		.poll		= hwdep_poll,
266 		.ioctl		= hwdep_ioctl,
267 		.ioctl_compat	= hwdep_compat_ioctl,
268 	};
269 	struct snd_hwdep *hwdep;
270 	int err;
271 
272 	err = snd_hwdep_new(motu->card, motu->card->driver, 0, &hwdep);
273 	if (err < 0)
274 		return err;
275 
276 	strscpy(hwdep->name, "MOTU");
277 	hwdep->iface = SNDRV_HWDEP_IFACE_FW_MOTU;
278 	hwdep->ops = ops;
279 	hwdep->private_data = motu;
280 	hwdep->exclusive = true;
281 
282 	motu->hwdep = hwdep;
283 
284 	return 0;
285 }
286