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 mutex_lock(&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 mutex_unlock(&sound_oss_mutex); 41 return private_data; 42 } 43 EXPORT_SYMBOL(snd_lookup_oss_minor_data); 44 45 static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev) 46 { 47 int minor; 48 49 switch (type) { 50 case SNDRV_OSS_DEVICE_TYPE_MIXER: 51 if (snd_BUG_ON(!card || dev < 0 || dev > 1)) 52 return -EINVAL; 53 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER)); 54 break; 55 case SNDRV_OSS_DEVICE_TYPE_SEQUENCER: 56 minor = SNDRV_MINOR_OSS_SEQUENCER; 57 break; 58 case SNDRV_OSS_DEVICE_TYPE_MUSIC: 59 minor = SNDRV_MINOR_OSS_MUSIC; 60 break; 61 case SNDRV_OSS_DEVICE_TYPE_PCM: 62 if (snd_BUG_ON(!card || dev < 0 || dev > 1)) 63 return -EINVAL; 64 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM)); 65 break; 66 case SNDRV_OSS_DEVICE_TYPE_MIDI: 67 if (snd_BUG_ON(!card || dev < 0 || dev > 1)) 68 return -EINVAL; 69 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIDI1 : SNDRV_MINOR_OSS_MIDI)); 70 break; 71 case SNDRV_OSS_DEVICE_TYPE_DMFM: 72 minor = SNDRV_MINOR_OSS(card->number, SNDRV_MINOR_OSS_DMFM); 73 break; 74 case SNDRV_OSS_DEVICE_TYPE_SNDSTAT: 75 minor = SNDRV_MINOR_OSS_SNDSTAT; 76 break; 77 default: 78 return -EINVAL; 79 } 80 if (minor < 0 || minor >= SNDRV_OSS_MINORS) 81 return -EINVAL; 82 return minor; 83 } 84 85 int snd_register_oss_device(int type, struct snd_card *card, int dev, 86 const struct file_operations *f_ops, void *private_data) 87 { 88 int minor = snd_oss_kernel_minor(type, card, dev); 89 int minor_unit; 90 struct snd_minor *preg; 91 int cidx = SNDRV_MINOR_OSS_CARD(minor); 92 int track2 = -1; 93 int register1 = -1, register2 = -1; 94 struct device *carddev = snd_card_get_device_link(card); 95 96 if (card && card->number >= SNDRV_MINOR_OSS_DEVICES) 97 return 0; /* ignore silently */ 98 if (minor < 0) 99 return minor; 100 preg = kmalloc(sizeof(struct snd_minor), GFP_KERNEL); 101 if (preg == NULL) 102 return -ENOMEM; 103 preg->type = type; 104 preg->card = card ? card->number : -1; 105 preg->device = dev; 106 preg->f_ops = f_ops; 107 preg->private_data = private_data; 108 preg->card_ptr = card; 109 mutex_lock(&sound_oss_mutex); 110 snd_oss_minors[minor] = preg; 111 minor_unit = SNDRV_MINOR_OSS_DEVICE(minor); 112 switch (minor_unit) { 113 case SNDRV_MINOR_OSS_PCM: 114 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO); 115 break; 116 case SNDRV_MINOR_OSS_MIDI: 117 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI); 118 break; 119 case SNDRV_MINOR_OSS_MIDI1: 120 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1); 121 break; 122 } 123 register1 = register_sound_special_device(f_ops, minor, carddev); 124 if (register1 != minor) 125 goto __end; 126 if (track2 >= 0) { 127 register2 = register_sound_special_device(f_ops, track2, 128 carddev); 129 if (register2 != track2) 130 goto __end; 131 snd_oss_minors[track2] = preg; 132 } 133 mutex_unlock(&sound_oss_mutex); 134 return 0; 135 136 __end: 137 if (register2 >= 0) 138 unregister_sound_special(register2); 139 if (register1 >= 0) 140 unregister_sound_special(register1); 141 snd_oss_minors[minor] = NULL; 142 mutex_unlock(&sound_oss_mutex); 143 kfree(preg); 144 return -EBUSY; 145 } 146 EXPORT_SYMBOL(snd_register_oss_device); 147 148 int snd_unregister_oss_device(int type, struct snd_card *card, int dev) 149 { 150 int minor = snd_oss_kernel_minor(type, card, dev); 151 int cidx = SNDRV_MINOR_OSS_CARD(minor); 152 int track2 = -1; 153 struct snd_minor *mptr; 154 155 if (card && card->number >= SNDRV_MINOR_OSS_DEVICES) 156 return 0; 157 if (minor < 0) 158 return minor; 159 mutex_lock(&sound_oss_mutex); 160 mptr = snd_oss_minors[minor]; 161 if (mptr == NULL) { 162 mutex_unlock(&sound_oss_mutex); 163 return -ENOENT; 164 } 165 switch (SNDRV_MINOR_OSS_DEVICE(minor)) { 166 case SNDRV_MINOR_OSS_PCM: 167 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO); 168 break; 169 case SNDRV_MINOR_OSS_MIDI: 170 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI); 171 break; 172 case SNDRV_MINOR_OSS_MIDI1: 173 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1); 174 break; 175 } 176 if (track2 >= 0) 177 snd_oss_minors[track2] = NULL; 178 snd_oss_minors[minor] = NULL; 179 mutex_unlock(&sound_oss_mutex); 180 181 /* call unregister_sound_special() outside sound_oss_mutex; 182 * otherwise may deadlock, as it can trigger the release of a card 183 */ 184 unregister_sound_special(minor); 185 if (track2 >= 0) 186 unregister_sound_special(track2); 187 188 kfree(mptr); 189 return 0; 190 } 191 EXPORT_SYMBOL(snd_unregister_oss_device); 192 193 /* 194 * INFO PART 195 */ 196 197 #ifdef CONFIG_SND_PROC_FS 198 static const char *snd_oss_device_type_name(int type) 199 { 200 switch (type) { 201 case SNDRV_OSS_DEVICE_TYPE_MIXER: 202 return "mixer"; 203 case SNDRV_OSS_DEVICE_TYPE_SEQUENCER: 204 case SNDRV_OSS_DEVICE_TYPE_MUSIC: 205 return "sequencer"; 206 case SNDRV_OSS_DEVICE_TYPE_PCM: 207 return "digital audio"; 208 case SNDRV_OSS_DEVICE_TYPE_MIDI: 209 return "raw midi"; 210 case SNDRV_OSS_DEVICE_TYPE_DMFM: 211 return "hardware dependent"; 212 default: 213 return "?"; 214 } 215 } 216 217 static void snd_minor_info_oss_read(struct snd_info_entry *entry, 218 struct snd_info_buffer *buffer) 219 { 220 int minor; 221 struct snd_minor *mptr; 222 223 mutex_lock(&sound_oss_mutex); 224 for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) { 225 mptr = snd_oss_minors[minor]; 226 if (!mptr) 227 continue; 228 if (mptr->card >= 0) 229 snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor, 230 mptr->card, mptr->device, 231 snd_oss_device_type_name(mptr->type)); 232 else 233 snd_iprintf(buffer, "%3i: : %s\n", minor, 234 snd_oss_device_type_name(mptr->type)); 235 } 236 mutex_unlock(&sound_oss_mutex); 237 } 238 239 240 int __init snd_minor_info_oss_init(void) 241 { 242 struct snd_info_entry *entry; 243 244 entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root); 245 if (!entry) 246 return -ENOMEM; 247 entry->c.text.read = snd_minor_info_oss_read; 248 return snd_info_register(entry); /* freed in error path */ 249 } 250 #endif /* CONFIG_SND_PROC_FS */ 251