1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 #ifndef __SOUND_CONTROL_H 3 #define __SOUND_CONTROL_H 4 5 /* 6 * Header file for control interface 7 * Copyright (c) by Jaroslav Kysela <perex@perex.cz> 8 */ 9 10 #include <linux/wait.h> 11 #include <linux/nospec.h> 12 #include <sound/asound.h> 13 14 #define snd_kcontrol_chip(kcontrol) ((kcontrol)->private_data) 15 16 struct snd_kcontrol; 17 typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo); 18 typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol); 19 typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol); 20 typedef int (snd_kcontrol_tlv_rw_t)(struct snd_kcontrol *kcontrol, 21 int op_flag, /* SNDRV_CTL_TLV_OP_XXX */ 22 unsigned int size, 23 unsigned int __user *tlv); 24 25 /* internal flag for skipping validations */ 26 #ifdef CONFIG_SND_CTL_DEBUG 27 #define SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK (1 << 24) 28 #define snd_ctl_skip_validation(info) \ 29 ((info)->access & SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK) 30 #else 31 #define SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK 0 32 #define snd_ctl_skip_validation(info) true 33 #endif 34 35 /* kernel only - LED bits */ 36 #define SNDRV_CTL_ELEM_ACCESS_LED_SHIFT 25 37 #define SNDRV_CTL_ELEM_ACCESS_LED_MASK (7<<25) /* kernel three bits - LED group */ 38 #define SNDRV_CTL_ELEM_ACCESS_SPK_LED (1<<25) /* kernel speaker (output) LED flag */ 39 #define SNDRV_CTL_ELEM_ACCESS_MIC_LED (2<<25) /* kernel microphone (input) LED flag */ 40 41 enum { 42 SNDRV_CTL_TLV_OP_READ = 0, 43 SNDRV_CTL_TLV_OP_WRITE = 1, 44 SNDRV_CTL_TLV_OP_CMD = -1, 45 }; 46 47 struct snd_kcontrol_new { 48 snd_ctl_elem_iface_t iface; /* interface identifier */ 49 unsigned int device; /* device/client number */ 50 unsigned int subdevice; /* subdevice (substream) number */ 51 const char *name; /* ASCII name of item */ 52 unsigned int index; /* index of item */ 53 unsigned int access; /* access rights */ 54 unsigned int count; /* count of same elements */ 55 snd_kcontrol_info_t *info; 56 snd_kcontrol_get_t *get; 57 snd_kcontrol_put_t *put; 58 union { 59 snd_kcontrol_tlv_rw_t *c; 60 const unsigned int *p; 61 } tlv; 62 unsigned long private_value; 63 }; 64 65 struct snd_kcontrol_volatile { 66 struct snd_ctl_file *owner; /* locked */ 67 unsigned int access; /* access rights */ 68 }; 69 70 struct snd_kcontrol { 71 struct list_head list; /* list of controls */ 72 struct snd_ctl_elem_id id; 73 unsigned int count; /* count of same elements */ 74 snd_kcontrol_info_t *info; 75 snd_kcontrol_get_t *get; 76 snd_kcontrol_put_t *put; 77 union { 78 snd_kcontrol_tlv_rw_t *c; 79 const unsigned int *p; 80 } tlv; 81 unsigned long private_value; 82 void *private_data; 83 void (*private_free)(struct snd_kcontrol *kcontrol); 84 struct snd_kcontrol_volatile vd[]; /* volatile data */ 85 }; 86 87 #define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list) 88 89 struct snd_kctl_event { 90 struct list_head list; /* list of events */ 91 struct snd_ctl_elem_id id; 92 unsigned int mask; 93 }; 94 95 #define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list) 96 97 struct pid; 98 99 enum { 100 SND_CTL_SUBDEV_PCM, 101 SND_CTL_SUBDEV_RAWMIDI, 102 SND_CTL_SUBDEV_ITEMS, 103 }; 104 105 struct snd_ctl_file { 106 struct list_head list; /* list of all control files */ 107 struct snd_card *card; 108 struct pid *pid; 109 int preferred_subdevice[SND_CTL_SUBDEV_ITEMS]; 110 wait_queue_head_t change_sleep; 111 spinlock_t read_lock; 112 struct snd_fasync *fasync; 113 int subscribed; /* read interface is activated */ 114 struct list_head events; /* waiting events for read */ 115 }; 116 117 struct snd_ctl_layer_ops { 118 struct snd_ctl_layer_ops *next; 119 const char *module_name; 120 void (*lregister)(struct snd_card *card); 121 void (*ldisconnect)(struct snd_card *card); 122 void (*lnotify)(struct snd_card *card, unsigned int mask, struct snd_kcontrol *kctl, unsigned int ioff); 123 }; 124 125 #define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list) 126 127 typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card, 128 struct snd_ctl_file * control, 129 unsigned int cmd, unsigned long arg); 130 131 void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id); 132 void snd_ctl_notify_one(struct snd_card * card, unsigned int mask, struct snd_kcontrol * kctl, unsigned int ioff); 133 134 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data); 135 void snd_ctl_free_one(struct snd_kcontrol * kcontrol); 136 int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol); 137 int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol); 138 int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace); 139 int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id); 140 int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id); 141 void snd_ctl_rename(struct snd_card *card, struct snd_kcontrol *kctl, const char *name); 142 int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id, int active); 143 struct snd_kcontrol *snd_ctl_find_numid_locked(struct snd_card *card, unsigned int numid); 144 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid); 145 struct snd_kcontrol *snd_ctl_find_id_locked(struct snd_card *card, const struct snd_ctl_elem_id *id); 146 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, const struct snd_ctl_elem_id *id); 147 148 /** 149 * snd_ctl_find_id_mixer - find the control instance with the given name string 150 * @card: the card instance 151 * @name: the name string 152 * 153 * Finds the control instance with the given name and 154 * @SNDRV_CTL_ELEM_IFACE_MIXER. Other fields are set to zero. 155 * 156 * This is merely a wrapper to snd_ctl_find_id(). 157 * 158 * Return: The pointer of the instance if found, or %NULL if not. 159 */ 160 static inline struct snd_kcontrol * 161 snd_ctl_find_id_mixer(struct snd_card *card, const char *name) 162 { 163 struct snd_ctl_elem_id id = {}; 164 165 id.iface = SNDRV_CTL_ELEM_IFACE_MIXER; 166 strscpy(id.name, name, sizeof(id.name)); 167 return snd_ctl_find_id(card, &id); 168 } 169 170 int snd_ctl_create(struct snd_card *card); 171 172 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn); 173 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn); 174 #ifdef CONFIG_COMPAT 175 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn); 176 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn); 177 #else 178 #define snd_ctl_register_ioctl_compat(fcn) 179 #define snd_ctl_unregister_ioctl_compat(fcn) 180 #endif 181 182 int snd_ctl_request_layer(const char *module_name); 183 void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops); 184 void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops); 185 186 int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type); 187 188 static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) 189 { 190 unsigned int ioff = id->numid - kctl->id.numid; 191 return array_index_nospec(ioff, kctl->count); 192 } 193 194 static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) 195 { 196 unsigned int ioff = id->index - kctl->id.index; 197 return array_index_nospec(ioff, kctl->count); 198 } 199 200 static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) 201 { 202 if (id->numid) { 203 return snd_ctl_get_ioffnum(kctl, id); 204 } else { 205 return snd_ctl_get_ioffidx(kctl, id); 206 } 207 } 208 209 static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id, 210 struct snd_kcontrol *src_kctl, 211 unsigned int offset) 212 { 213 *dst_id = src_kctl->id; 214 dst_id->index += offset; 215 dst_id->numid += offset; 216 return dst_id; 217 } 218 219 /* 220 * Frequently used control callbacks/helpers 221 */ 222 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol, 223 struct snd_ctl_elem_info *uinfo); 224 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol, 225 struct snd_ctl_elem_info *uinfo); 226 int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels, 227 unsigned int items, const char *const names[]); 228 229 /* 230 * virtual master control 231 */ 232 struct snd_kcontrol *snd_ctl_make_virtual_master(char *name, 233 const unsigned int *tlv); 234 int _snd_ctl_add_follower(struct snd_kcontrol *master, 235 struct snd_kcontrol *follower, 236 unsigned int flags); 237 /* optional flags for follower */ 238 #define SND_CTL_FOLLOWER_NEED_UPDATE (1 << 0) 239 240 /** 241 * snd_ctl_add_follower - Add a virtual follower control 242 * @master: vmaster element 243 * @follower: follower element to add 244 * 245 * Add a virtual follower control to the given master element created via 246 * snd_ctl_create_virtual_master() beforehand. 247 * 248 * All followers must be the same type (returning the same information 249 * via info callback). The function doesn't check it, so it's your 250 * responsibility. 251 * 252 * Also, some additional limitations: 253 * at most two channels, 254 * logarithmic volume control (dB level) thus no linear volume, 255 * master can only attenuate the volume without gain 256 * 257 * Return: Zero if successful or a negative error code. 258 */ 259 static inline int 260 snd_ctl_add_follower(struct snd_kcontrol *master, struct snd_kcontrol *follower) 261 { 262 return _snd_ctl_add_follower(master, follower, 0); 263 } 264 265 int snd_ctl_add_followers(struct snd_card *card, struct snd_kcontrol *master, 266 const char * const *list); 267 268 /** 269 * snd_ctl_add_follower_uncached - Add a virtual follower control 270 * @master: vmaster element 271 * @follower: follower element to add 272 * 273 * Add a virtual follower control to the given master. 274 * Unlike snd_ctl_add_follower(), the element added via this function 275 * is supposed to have volatile values, and get callback is called 276 * at each time queried from the master. 277 * 278 * When the control peeks the hardware values directly and the value 279 * can be changed by other means than the put callback of the element, 280 * this function should be used to keep the value always up-to-date. 281 * 282 * Return: Zero if successful or a negative error code. 283 */ 284 static inline int 285 snd_ctl_add_follower_uncached(struct snd_kcontrol *master, 286 struct snd_kcontrol *follower) 287 { 288 return _snd_ctl_add_follower(master, follower, SND_CTL_FOLLOWER_NEED_UPDATE); 289 } 290 291 int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl, 292 void (*hook)(void *private_data, int), 293 void *private_data); 294 void snd_ctl_sync_vmaster(struct snd_kcontrol *kctl, bool hook_only); 295 #define snd_ctl_sync_vmaster_hook(kctl) snd_ctl_sync_vmaster(kctl, true) 296 int snd_ctl_apply_vmaster_followers(struct snd_kcontrol *kctl, 297 int (*func)(struct snd_kcontrol *vfollower, 298 struct snd_kcontrol *follower, 299 void *arg), 300 void *arg); 301 302 /* 303 * Control LED trigger layer 304 */ 305 #define SND_CTL_LAYER_MODULE_LED "snd-ctl-led" 306 307 #if IS_MODULE(CONFIG_SND_CTL_LED) 308 static inline int snd_ctl_led_request(void) { return snd_ctl_request_layer(SND_CTL_LAYER_MODULE_LED); } 309 #else 310 static inline int snd_ctl_led_request(void) { return 0; } 311 #endif 312 313 /* 314 * Helper functions for jack-detection controls 315 */ 316 struct snd_kcontrol * 317 snd_kctl_jack_new(const char *name, struct snd_card *card); 318 void snd_kctl_jack_report(struct snd_card *card, 319 struct snd_kcontrol *kctl, bool status); 320 321 #endif /* __SOUND_CONTROL_H */ 322