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[] __counted_by(count); /* 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(struct snd_card *card, unsigned int numid); 144 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, const struct snd_ctl_elem_id *id); 145 146 /** 147 * snd_ctl_find_id_mixer - find the control instance with the given name string 148 * @card: the card instance 149 * @name: the name string 150 * 151 * Finds the control instance with the given name and 152 * @SNDRV_CTL_ELEM_IFACE_MIXER. Other fields are set to zero. 153 * 154 * This is merely a wrapper to snd_ctl_find_id(). 155 * 156 * Return: The pointer of the instance if found, or %NULL if not. 157 */ 158 static inline struct snd_kcontrol * 159 snd_ctl_find_id_mixer(struct snd_card *card, const char *name) 160 { 161 struct snd_ctl_elem_id id = {}; 162 163 id.iface = SNDRV_CTL_ELEM_IFACE_MIXER; 164 strscpy(id.name, name, sizeof(id.name)); 165 return snd_ctl_find_id(card, &id); 166 } 167 168 int snd_ctl_create(struct snd_card *card); 169 170 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn); 171 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn); 172 #ifdef CONFIG_COMPAT 173 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn); 174 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn); 175 #else 176 #define snd_ctl_register_ioctl_compat(fcn) 177 #define snd_ctl_unregister_ioctl_compat(fcn) 178 #endif 179 180 int snd_ctl_request_layer(const char *module_name); 181 void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops); 182 void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops); 183 184 int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type); 185 186 static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) 187 { 188 unsigned int ioff = id->numid - kctl->id.numid; 189 return array_index_nospec(ioff, kctl->count); 190 } 191 192 static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) 193 { 194 unsigned int ioff = id->index - kctl->id.index; 195 return array_index_nospec(ioff, kctl->count); 196 } 197 198 static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id) 199 { 200 if (id->numid) { 201 return snd_ctl_get_ioffnum(kctl, id); 202 } else { 203 return snd_ctl_get_ioffidx(kctl, id); 204 } 205 } 206 207 static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id, 208 struct snd_kcontrol *src_kctl, 209 unsigned int offset) 210 { 211 *dst_id = src_kctl->id; 212 dst_id->index += offset; 213 dst_id->numid += offset; 214 return dst_id; 215 } 216 217 /* 218 * Frequently used control callbacks/helpers 219 */ 220 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol, 221 struct snd_ctl_elem_info *uinfo); 222 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol, 223 struct snd_ctl_elem_info *uinfo); 224 int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels, 225 unsigned int items, const char *const names[]); 226 227 /* 228 * virtual master control 229 */ 230 struct snd_kcontrol *snd_ctl_make_virtual_master(char *name, 231 const unsigned int *tlv); 232 int _snd_ctl_add_follower(struct snd_kcontrol *master, 233 struct snd_kcontrol *follower, 234 unsigned int flags); 235 /* optional flags for follower */ 236 #define SND_CTL_FOLLOWER_NEED_UPDATE (1 << 0) 237 238 /** 239 * snd_ctl_add_follower - Add a virtual follower control 240 * @master: vmaster element 241 * @follower: follower element to add 242 * 243 * Add a virtual follower control to the given master element created via 244 * snd_ctl_create_virtual_master() beforehand. 245 * 246 * All followers must be the same type (returning the same information 247 * via info callback). The function doesn't check it, so it's your 248 * responsibility. 249 * 250 * Also, some additional limitations: 251 * at most two channels, 252 * logarithmic volume control (dB level) thus no linear volume, 253 * master can only attenuate the volume without gain 254 * 255 * Return: Zero if successful or a negative error code. 256 */ 257 static inline int 258 snd_ctl_add_follower(struct snd_kcontrol *master, struct snd_kcontrol *follower) 259 { 260 return _snd_ctl_add_follower(master, follower, 0); 261 } 262 263 int snd_ctl_add_followers(struct snd_card *card, struct snd_kcontrol *master, 264 const char * const *list); 265 266 /** 267 * snd_ctl_add_follower_uncached - Add a virtual follower control 268 * @master: vmaster element 269 * @follower: follower element to add 270 * 271 * Add a virtual follower control to the given master. 272 * Unlike snd_ctl_add_follower(), the element added via this function 273 * is supposed to have volatile values, and get callback is called 274 * at each time queried from the master. 275 * 276 * When the control peeks the hardware values directly and the value 277 * can be changed by other means than the put callback of the element, 278 * this function should be used to keep the value always up-to-date. 279 * 280 * Return: Zero if successful or a negative error code. 281 */ 282 static inline int 283 snd_ctl_add_follower_uncached(struct snd_kcontrol *master, 284 struct snd_kcontrol *follower) 285 { 286 return _snd_ctl_add_follower(master, follower, SND_CTL_FOLLOWER_NEED_UPDATE); 287 } 288 289 int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl, 290 void (*hook)(void *private_data, int), 291 void *private_data); 292 void snd_ctl_sync_vmaster(struct snd_kcontrol *kctl, bool hook_only); 293 #define snd_ctl_sync_vmaster_hook(kctl) snd_ctl_sync_vmaster(kctl, true) 294 int snd_ctl_apply_vmaster_followers(struct snd_kcontrol *kctl, 295 int (*func)(struct snd_kcontrol *vfollower, 296 struct snd_kcontrol *follower, 297 void *arg), 298 void *arg); 299 300 /* 301 * Control LED trigger layer 302 */ 303 #define SND_CTL_LAYER_MODULE_LED "snd-ctl-led" 304 305 #if IS_MODULE(CONFIG_SND_CTL_LED) 306 static inline int snd_ctl_led_request(void) { return snd_ctl_request_layer(SND_CTL_LAYER_MODULE_LED); } 307 #else 308 static inline int snd_ctl_led_request(void) { return 0; } 309 #endif 310 311 /* 312 * Helper functions for jack-detection controls 313 */ 314 struct snd_kcontrol * 315 snd_kctl_jack_new(const char *name, struct snd_card *card); 316 void snd_kctl_jack_report(struct snd_card *card, 317 struct snd_kcontrol *kctl, bool status); 318 319 #endif /* __SOUND_CONTROL_H */ 320