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
19static 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
27static 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(lock: &motu->lock);
35
36 while (!motu->dev_lock_changed && motu->msg == 0 && !has_dsp_event(motu)) {
37 prepare_to_wait(wq_head: &motu->hwdep_wait, wq_entry: &wait, TASK_INTERRUPTIBLE);
38 spin_unlock_irq(lock: &motu->lock);
39 schedule();
40 finish_wait(wq_head: &motu->hwdep_wait, wq_entry: &wait);
41 if (signal_pending(current))
42 return -ERESTARTSYS;
43 spin_lock_irq(lock: &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(lock: &motu->lock);
52
53 count = min_t(long, count, sizeof(event));
54 if (copy_to_user(to: buf, from: &event, n: 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(lock: &motu->lock);
61
62 count = min_t(long, count, sizeof(event));
63 if (copy_to_user(to: buf, from: &event, n: 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(lock: &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, event: &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(to: buf, from: &event, n: sizeof(event.motu_register_dsp_change)))
87 return -EFAULT;
88
89 count = consumed;
90 } else {
91 spin_unlock_irq(lock: &motu->lock);
92
93 count = 0;
94 }
95
96 return count;
97}
98
99static __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 __poll_t events;
104
105 poll_wait(filp: file, wait_address: &motu->hwdep_wait, p: wait);
106
107 spin_lock_irq(lock: &motu->lock);
108 if (motu->dev_lock_changed || motu->msg || has_dsp_event(motu))
109 events = EPOLLIN | EPOLLRDNORM;
110 else
111 events = 0;
112 spin_unlock_irq(lock: &motu->lock);
113
114 return events | EPOLLOUT;
115}
116
117static int hwdep_get_info(struct snd_motu *motu, void __user *arg)
118{
119 struct fw_device *dev = fw_parent_device(motu->unit);
120 struct snd_firewire_get_info info;
121
122 memset(&info, 0, sizeof(info));
123 info.type = SNDRV_FIREWIRE_TYPE_MOTU;
124 info.card = dev->card->index;
125 *(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
126 *(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
127 strscpy(info.device_name, dev_name(&dev->device),
128 sizeof(info.device_name));
129
130 if (copy_to_user(to: arg, from: &info, n: sizeof(info)))
131 return -EFAULT;
132
133 return 0;
134}
135
136static int hwdep_lock(struct snd_motu *motu)
137{
138 int err;
139
140 spin_lock_irq(lock: &motu->lock);
141
142 if (motu->dev_lock_count == 0) {
143 motu->dev_lock_count = -1;
144 err = 0;
145 } else {
146 err = -EBUSY;
147 }
148
149 spin_unlock_irq(lock: &motu->lock);
150
151 return err;
152}
153
154static int hwdep_unlock(struct snd_motu *motu)
155{
156 int err;
157
158 spin_lock_irq(lock: &motu->lock);
159
160 if (motu->dev_lock_count == -1) {
161 motu->dev_lock_count = 0;
162 err = 0;
163 } else {
164 err = -EBADFD;
165 }
166
167 spin_unlock_irq(lock: &motu->lock);
168
169 return err;
170}
171
172static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
173{
174 struct snd_motu *motu = hwdep->private_data;
175
176 spin_lock_irq(lock: &motu->lock);
177 if (motu->dev_lock_count == -1)
178 motu->dev_lock_count = 0;
179 spin_unlock_irq(lock: &motu->lock);
180
181 return 0;
182}
183
184static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
185 unsigned int cmd, unsigned long arg)
186{
187 struct snd_motu *motu = hwdep->private_data;
188
189 switch (cmd) {
190 case SNDRV_FIREWIRE_IOCTL_GET_INFO:
191 return hwdep_get_info(motu, arg: (void __user *)arg);
192 case SNDRV_FIREWIRE_IOCTL_LOCK:
193 return hwdep_lock(motu);
194 case SNDRV_FIREWIRE_IOCTL_UNLOCK:
195 return hwdep_unlock(motu);
196 case SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_METER:
197 {
198 struct snd_firewire_motu_register_dsp_meter *meter;
199 int err;
200
201 if (!(motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP))
202 return -ENXIO;
203
204 meter = kzalloc(size: sizeof(*meter), GFP_KERNEL);
205 if (!meter)
206 return -ENOMEM;
207
208 snd_motu_register_dsp_message_parser_copy_meter(motu, meter);
209
210 err = copy_to_user(to: (void __user *)arg, from: meter, n: sizeof(*meter));
211 kfree(objp: meter);
212
213 if (err)
214 return -EFAULT;
215
216 return 0;
217 }
218 case SNDRV_FIREWIRE_IOCTL_MOTU_COMMAND_DSP_METER:
219 {
220 struct snd_firewire_motu_command_dsp_meter *meter;
221 int err;
222
223 if (!(motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP))
224 return -ENXIO;
225
226 meter = kzalloc(size: sizeof(*meter), GFP_KERNEL);
227 if (!meter)
228 return -ENOMEM;
229
230 snd_motu_command_dsp_message_parser_copy_meter(motu, meter);
231
232 err = copy_to_user(to: (void __user *)arg, from: meter, n: sizeof(*meter));
233 kfree(objp: meter);
234
235 if (err)
236 return -EFAULT;
237
238 return 0;
239 }
240 case SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_PARAMETER:
241 {
242 struct snd_firewire_motu_register_dsp_parameter *param;
243 int err;
244
245 if (!(motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP))
246 return -ENXIO;
247
248 param = kzalloc(size: sizeof(*param), GFP_KERNEL);
249 if (!param)
250 return -ENOMEM;
251
252 snd_motu_register_dsp_message_parser_copy_parameter(motu, params: param);
253
254 err = copy_to_user(to: (void __user *)arg, from: param, n: sizeof(*param));
255 kfree(objp: param);
256 if (err)
257 return -EFAULT;
258
259 return 0;
260 }
261 default:
262 return -ENOIOCTLCMD;
263 }
264}
265
266#ifdef CONFIG_COMPAT
267static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
268 unsigned int cmd, unsigned long arg)
269{
270 return hwdep_ioctl(hwdep, file, cmd,
271 arg: (unsigned long)compat_ptr(uptr: arg));
272}
273#else
274#define hwdep_compat_ioctl NULL
275#endif
276
277int snd_motu_create_hwdep_device(struct snd_motu *motu)
278{
279 static const struct snd_hwdep_ops ops = {
280 .read = hwdep_read,
281 .release = hwdep_release,
282 .poll = hwdep_poll,
283 .ioctl = hwdep_ioctl,
284 .ioctl_compat = hwdep_compat_ioctl,
285 };
286 struct snd_hwdep *hwdep;
287 int err;
288
289 err = snd_hwdep_new(card: motu->card, id: motu->card->driver, device: 0, rhwdep: &hwdep);
290 if (err < 0)
291 return err;
292
293 strcpy(p: hwdep->name, q: "MOTU");
294 hwdep->iface = SNDRV_HWDEP_IFACE_FW_MOTU;
295 hwdep->ops = ops;
296 hwdep->private_data = motu;
297 hwdep->exclusive = true;
298
299 motu->hwdep = hwdep;
300
301 return 0;
302}
303

source code of linux/sound/firewire/motu/motu-hwdep.c