1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Advanced Linux Sound Architecture 4 * 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 256 18 19 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS]; 20 static DEFINE_MUTEX(sound_oss_mutex); 21 22 /* NOTE: This function increments the refcount of the associated card like 23 * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately 24 */ 25 void *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 } else 39 private_data = NULL; 40 return private_data; 41 } 42 EXPORT_SYMBOL(snd_lookup_oss_minor_data); 43 44 static 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 84 int 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 } 143 EXPORT_SYMBOL(snd_register_oss_device); 144 145 int 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 card 177 */ 178 unregister_sound_special(minor); 179 if (track2 >= 0) 180 unregister_sound_special(track2); 181 182 kfree(mptr); 183 return 0; 184 } 185 EXPORT_SYMBOL(snd_unregister_oss_device); 186 187 /* 188 * INFO PART 189 */ 190 191 #ifdef CONFIG_SND_PROC_FS 192 static 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 } 210 211 static 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 else 227 snd_iprintf(buffer, "%3i: : %s\n", minor, 228 snd_oss_device_type_name(mptr->type)); 229 } 230 } 231 232 233 int __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