Root/sound/core/hwdep.c

1/*
2 * Hardware dependent layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/major.h>
23#include <linux/init.h>
24#include <linux/slab.h>
25#include <linux/time.h>
26#include <linux/mutex.h>
27#include <sound/core.h>
28#include <sound/control.h>
29#include <sound/minors.h>
30#include <sound/hwdep.h>
31#include <sound/info.h>
32
33MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
34MODULE_DESCRIPTION("Hardware dependent layer");
35MODULE_LICENSE("GPL");
36
37static LIST_HEAD(snd_hwdep_devices);
38static DEFINE_MUTEX(register_mutex);
39
40static int snd_hwdep_free(struct snd_hwdep *hwdep);
41static int snd_hwdep_dev_free(struct snd_device *device);
42static int snd_hwdep_dev_register(struct snd_device *device);
43static int snd_hwdep_dev_disconnect(struct snd_device *device);
44
45
46static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
47{
48    struct snd_hwdep *hwdep;
49
50    list_for_each_entry(hwdep, &snd_hwdep_devices, list)
51        if (hwdep->card == card && hwdep->device == device)
52            return hwdep;
53    return NULL;
54}
55
56static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
57{
58    struct snd_hwdep *hw = file->private_data;
59    if (hw->ops.llseek)
60        return hw->ops.llseek(hw, file, offset, orig);
61    return -ENXIO;
62}
63
64static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
65                  size_t count, loff_t *offset)
66{
67    struct snd_hwdep *hw = file->private_data;
68    if (hw->ops.read)
69        return hw->ops.read(hw, buf, count, offset);
70    return -ENXIO;
71}
72
73static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
74                   size_t count, loff_t *offset)
75{
76    struct snd_hwdep *hw = file->private_data;
77    if (hw->ops.write)
78        return hw->ops.write(hw, buf, count, offset);
79    return -ENXIO;
80}
81
82static int snd_hwdep_open(struct inode *inode, struct file * file)
83{
84    int major = imajor(inode);
85    struct snd_hwdep *hw;
86    int err;
87    wait_queue_t wait;
88
89    if (major == snd_major) {
90        hw = snd_lookup_minor_data(iminor(inode),
91                       SNDRV_DEVICE_TYPE_HWDEP);
92#ifdef CONFIG_SND_OSSEMUL
93    } else if (major == SOUND_MAJOR) {
94        hw = snd_lookup_oss_minor_data(iminor(inode),
95                           SNDRV_OSS_DEVICE_TYPE_DMFM);
96#endif
97    } else
98        return -ENXIO;
99    if (hw == NULL)
100        return -ENODEV;
101
102    if (!try_module_get(hw->card->module))
103        return -EFAULT;
104
105    init_waitqueue_entry(&wait, current);
106    add_wait_queue(&hw->open_wait, &wait);
107    mutex_lock(&hw->open_mutex);
108    while (1) {
109        if (hw->exclusive && hw->used > 0) {
110            err = -EBUSY;
111            break;
112        }
113        if (!hw->ops.open) {
114            err = 0;
115            break;
116        }
117        err = hw->ops.open(hw, file);
118        if (err >= 0)
119            break;
120        if (err == -EAGAIN) {
121            if (file->f_flags & O_NONBLOCK) {
122                err = -EBUSY;
123                break;
124            }
125        } else
126            break;
127        set_current_state(TASK_INTERRUPTIBLE);
128        mutex_unlock(&hw->open_mutex);
129        schedule();
130        mutex_lock(&hw->open_mutex);
131        if (signal_pending(current)) {
132            err = -ERESTARTSYS;
133            break;
134        }
135    }
136    remove_wait_queue(&hw->open_wait, &wait);
137    if (err >= 0) {
138        err = snd_card_file_add(hw->card, file);
139        if (err >= 0) {
140            file->private_data = hw;
141            hw->used++;
142        } else {
143            if (hw->ops.release)
144                hw->ops.release(hw, file);
145        }
146    }
147    mutex_unlock(&hw->open_mutex);
148    if (err < 0)
149        module_put(hw->card->module);
150    return err;
151}
152
153static int snd_hwdep_release(struct inode *inode, struct file * file)
154{
155    int err = 0;
156    struct snd_hwdep *hw = file->private_data;
157    struct module *mod = hw->card->module;
158
159    mutex_lock(&hw->open_mutex);
160    if (hw->ops.release)
161        err = hw->ops.release(hw, file);
162    if (hw->used > 0)
163        hw->used--;
164    mutex_unlock(&hw->open_mutex);
165    wake_up(&hw->open_wait);
166
167    snd_card_file_remove(hw->card, file);
168    module_put(mod);
169    return err;
170}
171
172static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
173{
174    struct snd_hwdep *hw = file->private_data;
175    if (hw->ops.poll)
176        return hw->ops.poll(hw, file, wait);
177    return 0;
178}
179
180static int snd_hwdep_info(struct snd_hwdep *hw,
181              struct snd_hwdep_info __user *_info)
182{
183    struct snd_hwdep_info info;
184    
185    memset(&info, 0, sizeof(info));
186    info.card = hw->card->number;
187    strlcpy(info.id, hw->id, sizeof(info.id));
188    strlcpy(info.name, hw->name, sizeof(info.name));
189    info.iface = hw->iface;
190    if (copy_to_user(_info, &info, sizeof(info)))
191        return -EFAULT;
192    return 0;
193}
194
195static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
196                struct snd_hwdep_dsp_status __user *_info)
197{
198    struct snd_hwdep_dsp_status info;
199    int err;
200    
201    if (! hw->ops.dsp_status)
202        return -ENXIO;
203    memset(&info, 0, sizeof(info));
204    info.dsp_loaded = hw->dsp_loaded;
205    if ((err = hw->ops.dsp_status(hw, &info)) < 0)
206        return err;
207    if (copy_to_user(_info, &info, sizeof(info)))
208        return -EFAULT;
209    return 0;
210}
211
212static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
213                  struct snd_hwdep_dsp_image __user *_info)
214{
215    struct snd_hwdep_dsp_image info;
216    int err;
217    
218    if (! hw->ops.dsp_load)
219        return -ENXIO;
220    memset(&info, 0, sizeof(info));
221    if (copy_from_user(&info, _info, sizeof(info)))
222        return -EFAULT;
223    /* check whether the dsp was already loaded */
224    if (hw->dsp_loaded & (1 << info.index))
225        return -EBUSY;
226    if (!access_ok(VERIFY_READ, info.image, info.length))
227        return -EFAULT;
228    err = hw->ops.dsp_load(hw, &info);
229    if (err < 0)
230        return err;
231    hw->dsp_loaded |= (1 << info.index);
232    return 0;
233}
234
235static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
236                unsigned long arg)
237{
238    struct snd_hwdep *hw = file->private_data;
239    void __user *argp = (void __user *)arg;
240    switch (cmd) {
241    case SNDRV_HWDEP_IOCTL_PVERSION:
242        return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
243    case SNDRV_HWDEP_IOCTL_INFO:
244        return snd_hwdep_info(hw, argp);
245    case SNDRV_HWDEP_IOCTL_DSP_STATUS:
246        return snd_hwdep_dsp_status(hw, argp);
247    case SNDRV_HWDEP_IOCTL_DSP_LOAD:
248        return snd_hwdep_dsp_load(hw, argp);
249    }
250    if (hw->ops.ioctl)
251        return hw->ops.ioctl(hw, file, cmd, arg);
252    return -ENOTTY;
253}
254
255static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
256{
257    struct snd_hwdep *hw = file->private_data;
258    if (hw->ops.mmap)
259        return hw->ops.mmap(hw, file, vma);
260    return -ENXIO;
261}
262
263static int snd_hwdep_control_ioctl(struct snd_card *card,
264                   struct snd_ctl_file * control,
265                   unsigned int cmd, unsigned long arg)
266{
267    switch (cmd) {
268    case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
269        {
270            int device;
271
272            if (get_user(device, (int __user *)arg))
273                return -EFAULT;
274            mutex_lock(&register_mutex);
275            device = device < 0 ? 0 : device + 1;
276            while (device < SNDRV_MINOR_HWDEPS) {
277                if (snd_hwdep_search(card, device))
278                    break;
279                device++;
280            }
281            if (device >= SNDRV_MINOR_HWDEPS)
282                device = -1;
283            mutex_unlock(&register_mutex);
284            if (put_user(device, (int __user *)arg))
285                return -EFAULT;
286            return 0;
287        }
288    case SNDRV_CTL_IOCTL_HWDEP_INFO:
289        {
290            struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
291            int device, err;
292            struct snd_hwdep *hwdep;
293
294            if (get_user(device, &info->device))
295                return -EFAULT;
296            mutex_lock(&register_mutex);
297            hwdep = snd_hwdep_search(card, device);
298            if (hwdep)
299                err = snd_hwdep_info(hwdep, info);
300            else
301                err = -ENXIO;
302            mutex_unlock(&register_mutex);
303            return err;
304        }
305    }
306    return -ENOIOCTLCMD;
307}
308
309#ifdef CONFIG_COMPAT
310#include "hwdep_compat.c"
311#else
312#define snd_hwdep_ioctl_compat NULL
313#endif
314
315/*
316
317 */
318
319static const struct file_operations snd_hwdep_f_ops =
320{
321    .owner = THIS_MODULE,
322    .llseek = snd_hwdep_llseek,
323    .read = snd_hwdep_read,
324    .write = snd_hwdep_write,
325    .open = snd_hwdep_open,
326    .release = snd_hwdep_release,
327    .poll = snd_hwdep_poll,
328    .unlocked_ioctl = snd_hwdep_ioctl,
329    .compat_ioctl = snd_hwdep_ioctl_compat,
330    .mmap = snd_hwdep_mmap,
331};
332
333/**
334 * snd_hwdep_new - create a new hwdep instance
335 * @card: the card instance
336 * @id: the id string
337 * @device: the device index (zero-based)
338 * @rhwdep: the pointer to store the new hwdep instance
339 *
340 * Creates a new hwdep instance with the given index on the card.
341 * The callbacks (hwdep->ops) must be set on the returned instance
342 * after this call manually by the caller.
343 *
344 * Returns zero if successful, or a negative error code on failure.
345 */
346int snd_hwdep_new(struct snd_card *card, char *id, int device,
347          struct snd_hwdep **rhwdep)
348{
349    struct snd_hwdep *hwdep;
350    int err;
351    static struct snd_device_ops ops = {
352        .dev_free = snd_hwdep_dev_free,
353        .dev_register = snd_hwdep_dev_register,
354        .dev_disconnect = snd_hwdep_dev_disconnect,
355    };
356
357    if (snd_BUG_ON(!card))
358        return -ENXIO;
359    if (rhwdep)
360        *rhwdep = NULL;
361    hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
362    if (hwdep == NULL) {
363        snd_printk(KERN_ERR "hwdep: cannot allocate\n");
364        return -ENOMEM;
365    }
366    hwdep->card = card;
367    hwdep->device = device;
368    if (id)
369        strlcpy(hwdep->id, id, sizeof(hwdep->id));
370#ifdef CONFIG_SND_OSSEMUL
371    hwdep->oss_type = -1;
372#endif
373    if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
374        snd_hwdep_free(hwdep);
375        return err;
376    }
377    init_waitqueue_head(&hwdep->open_wait);
378    mutex_init(&hwdep->open_mutex);
379    if (rhwdep)
380        *rhwdep = hwdep;
381    return 0;
382}
383
384static int snd_hwdep_free(struct snd_hwdep *hwdep)
385{
386    if (!hwdep)
387        return 0;
388    if (hwdep->private_free)
389        hwdep->private_free(hwdep);
390    kfree(hwdep);
391    return 0;
392}
393
394static int snd_hwdep_dev_free(struct snd_device *device)
395{
396    struct snd_hwdep *hwdep = device->device_data;
397    return snd_hwdep_free(hwdep);
398}
399
400static int snd_hwdep_dev_register(struct snd_device *device)
401{
402    struct snd_hwdep *hwdep = device->device_data;
403    int err;
404    char name[32];
405
406    mutex_lock(&register_mutex);
407    if (snd_hwdep_search(hwdep->card, hwdep->device)) {
408        mutex_unlock(&register_mutex);
409        return -EBUSY;
410    }
411    list_add_tail(&hwdep->list, &snd_hwdep_devices);
412    sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
413    if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
414                       hwdep->card, hwdep->device,
415                       &snd_hwdep_f_ops, hwdep, name)) < 0) {
416        snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
417               hwdep->card->number, hwdep->device);
418        list_del(&hwdep->list);
419        mutex_unlock(&register_mutex);
420        return err;
421    }
422#ifdef CONFIG_SND_OSSEMUL
423    hwdep->ossreg = 0;
424    if (hwdep->oss_type >= 0) {
425        if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
426            snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
427        } else {
428            if (snd_register_oss_device(hwdep->oss_type,
429                            hwdep->card, hwdep->device,
430                            &snd_hwdep_f_ops, hwdep,
431                            hwdep->oss_dev) < 0) {
432                snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
433                       hwdep->card->number, hwdep->device);
434            } else
435                hwdep->ossreg = 1;
436        }
437    }
438#endif
439    mutex_unlock(&register_mutex);
440    return 0;
441}
442
443static int snd_hwdep_dev_disconnect(struct snd_device *device)
444{
445    struct snd_hwdep *hwdep = device->device_data;
446
447    if (snd_BUG_ON(!hwdep))
448        return -ENXIO;
449    mutex_lock(&register_mutex);
450    if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
451        mutex_unlock(&register_mutex);
452        return -EINVAL;
453    }
454#ifdef CONFIG_SND_OSSEMUL
455    if (hwdep->ossreg)
456        snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
457#endif
458    snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
459    list_del_init(&hwdep->list);
460    mutex_unlock(&register_mutex);
461    return 0;
462}
463
464#ifdef CONFIG_PROC_FS
465/*
466 * Info interface
467 */
468
469static void snd_hwdep_proc_read(struct snd_info_entry *entry,
470                struct snd_info_buffer *buffer)
471{
472    struct snd_hwdep *hwdep;
473
474    mutex_lock(&register_mutex);
475    list_for_each_entry(hwdep, &snd_hwdep_devices, list)
476        snd_iprintf(buffer, "%02i-%02i: %s\n",
477                hwdep->card->number, hwdep->device, hwdep->name);
478    mutex_unlock(&register_mutex);
479}
480
481static struct snd_info_entry *snd_hwdep_proc_entry;
482
483static void __init snd_hwdep_proc_init(void)
484{
485    struct snd_info_entry *entry;
486
487    if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
488        entry->c.text.read = snd_hwdep_proc_read;
489        if (snd_info_register(entry) < 0) {
490            snd_info_free_entry(entry);
491            entry = NULL;
492        }
493    }
494    snd_hwdep_proc_entry = entry;
495}
496
497static void __exit snd_hwdep_proc_done(void)
498{
499    snd_info_free_entry(snd_hwdep_proc_entry);
500}
501#else /* !CONFIG_PROC_FS */
502#define snd_hwdep_proc_init()
503#define snd_hwdep_proc_done()
504#endif /* CONFIG_PROC_FS */
505
506
507/*
508 * ENTRY functions
509 */
510
511static int __init alsa_hwdep_init(void)
512{
513    snd_hwdep_proc_init();
514    snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
515    snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
516    return 0;
517}
518
519static void __exit alsa_hwdep_exit(void)
520{
521    snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
522    snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
523    snd_hwdep_proc_done();
524}
525
526module_init(alsa_hwdep_init)
527module_exit(alsa_hwdep_exit)
528
529EXPORT_SYMBOL(snd_hwdep_new);
530

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