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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Advanced Linux Sound Architecture4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>5 */6 7#include <linux/init.h>8#include <linux/export.h>9#include <linux/slab.h>10#include <linux/time.h>11#include <sound/core.h>12#include <sound/minors.h>13#include <sound/info.h>14#include <linux/sound.h>15#include <linux/mutex.h>16 17#define SNDRV_OSS_MINORS 25618 19static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];20static DEFINE_MUTEX(sound_oss_mutex);21 22/* NOTE: This function increments the refcount of the associated card like23 * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately24 */25void *snd_lookup_oss_minor_data(unsigned int minor, int type)26{27 struct snd_minor *mreg;28 void *private_data;29 30 if (minor >= ARRAY_SIZE(snd_oss_minors))31 return NULL;32 guard(mutex)(&sound_oss_mutex);33 mreg = snd_oss_minors[minor];34 if (mreg && mreg->type == type) {35 private_data = mreg->private_data;36 if (private_data && mreg->card_ptr)37 get_device(&mreg->card_ptr->card_dev);38 } else39 private_data = NULL;40 return private_data;41}42EXPORT_SYMBOL(snd_lookup_oss_minor_data);43 44static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)45{46 int minor;47 48 switch (type) {49 case SNDRV_OSS_DEVICE_TYPE_MIXER:50 if (snd_BUG_ON(!card || dev < 0 || dev > 1))51 return -EINVAL;52 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER));53 break;54 case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:55 minor = SNDRV_MINOR_OSS_SEQUENCER;56 break;57 case SNDRV_OSS_DEVICE_TYPE_MUSIC:58 minor = SNDRV_MINOR_OSS_MUSIC;59 break;60 case SNDRV_OSS_DEVICE_TYPE_PCM:61 if (snd_BUG_ON(!card || dev < 0 || dev > 1))62 return -EINVAL;63 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM));64 break;65 case SNDRV_OSS_DEVICE_TYPE_MIDI:66 if (snd_BUG_ON(!card || dev < 0 || dev > 1))67 return -EINVAL;68 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIDI1 : SNDRV_MINOR_OSS_MIDI));69 break;70 case SNDRV_OSS_DEVICE_TYPE_DMFM:71 minor = SNDRV_MINOR_OSS(card->number, SNDRV_MINOR_OSS_DMFM);72 break;73 case SNDRV_OSS_DEVICE_TYPE_SNDSTAT:74 minor = SNDRV_MINOR_OSS_SNDSTAT;75 break;76 default:77 return -EINVAL;78 }79 if (minor < 0 || minor >= SNDRV_OSS_MINORS)80 return -EINVAL;81 return minor;82}83 84int snd_register_oss_device(int type, struct snd_card *card, int dev,85 const struct file_operations *f_ops, void *private_data)86{87 int minor = snd_oss_kernel_minor(type, card, dev);88 int minor_unit;89 struct snd_minor *preg;90 int cidx = SNDRV_MINOR_OSS_CARD(minor);91 int track2 = -1;92 int register1 = -1, register2 = -1;93 struct device *carddev = snd_card_get_device_link(card);94 95 if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)96 return 0; /* ignore silently */97 if (minor < 0)98 return minor;99 preg = kmalloc(sizeof(struct snd_minor), GFP_KERNEL);100 if (preg == NULL)101 return -ENOMEM;102 preg->type = type;103 preg->card = card ? card->number : -1;104 preg->device = dev;105 preg->f_ops = f_ops;106 preg->private_data = private_data;107 preg->card_ptr = card;108 guard(mutex)(&sound_oss_mutex);109 snd_oss_minors[minor] = preg;110 minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);111 switch (minor_unit) {112 case SNDRV_MINOR_OSS_PCM:113 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);114 break;115 case SNDRV_MINOR_OSS_MIDI:116 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);117 break;118 case SNDRV_MINOR_OSS_MIDI1:119 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);120 break;121 }122 register1 = register_sound_special_device(f_ops, minor, carddev);123 if (register1 != minor)124 goto __end;125 if (track2 >= 0) {126 register2 = register_sound_special_device(f_ops, track2,127 carddev);128 if (register2 != track2)129 goto __end;130 snd_oss_minors[track2] = preg;131 }132 return 0;133 134 __end:135 if (register2 >= 0)136 unregister_sound_special(register2);137 if (register1 >= 0)138 unregister_sound_special(register1);139 snd_oss_minors[minor] = NULL;140 kfree(preg);141 return -EBUSY;142}143EXPORT_SYMBOL(snd_register_oss_device);144 145int snd_unregister_oss_device(int type, struct snd_card *card, int dev)146{147 int minor = snd_oss_kernel_minor(type, card, dev);148 int cidx = SNDRV_MINOR_OSS_CARD(minor);149 int track2 = -1;150 struct snd_minor *mptr;151 152 if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)153 return 0;154 if (minor < 0)155 return minor;156 guard(mutex)(&sound_oss_mutex);157 mptr = snd_oss_minors[minor];158 if (mptr == NULL)159 return -ENOENT;160 switch (SNDRV_MINOR_OSS_DEVICE(minor)) {161 case SNDRV_MINOR_OSS_PCM:162 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);163 break;164 case SNDRV_MINOR_OSS_MIDI:165 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);166 break;167 case SNDRV_MINOR_OSS_MIDI1:168 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);169 break;170 }171 if (track2 >= 0)172 snd_oss_minors[track2] = NULL;173 snd_oss_minors[minor] = NULL;174 175 /* call unregister_sound_special() outside sound_oss_mutex;176 * otherwise may deadlock, as it can trigger the release of a card177 */178 unregister_sound_special(minor);179 if (track2 >= 0)180 unregister_sound_special(track2);181 182 kfree(mptr);183 return 0;184}185EXPORT_SYMBOL(snd_unregister_oss_device);186 187/*188 * INFO PART189 */190 191#ifdef CONFIG_SND_PROC_FS192static const char *snd_oss_device_type_name(int type)193{194 switch (type) {195 case SNDRV_OSS_DEVICE_TYPE_MIXER:196 return "mixer";197 case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:198 case SNDRV_OSS_DEVICE_TYPE_MUSIC:199 return "sequencer";200 case SNDRV_OSS_DEVICE_TYPE_PCM:201 return "digital audio";202 case SNDRV_OSS_DEVICE_TYPE_MIDI:203 return "raw midi";204 case SNDRV_OSS_DEVICE_TYPE_DMFM:205 return "hardware dependent";206 default:207 return "?";208 }209}210 211static void snd_minor_info_oss_read(struct snd_info_entry *entry,212 struct snd_info_buffer *buffer)213{214 int minor;215 struct snd_minor *mptr;216 217 guard(mutex)(&sound_oss_mutex);218 for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) {219 mptr = snd_oss_minors[minor];220 if (!mptr)221 continue;222 if (mptr->card >= 0)223 snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor,224 mptr->card, mptr->device,225 snd_oss_device_type_name(mptr->type));226 else227 snd_iprintf(buffer, "%3i: : %s\n", minor,228 snd_oss_device_type_name(mptr->type));229 }230}231 232 233int __init snd_minor_info_oss_init(void)234{235 struct snd_info_entry *entry;236 237 entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);238 if (!entry)239 return -ENOMEM;240 entry->c.text.read = snd_minor_info_oss_read;241 return snd_info_register(entry); /* freed in error path */242}243#endif /* CONFIG_SND_PROC_FS */244