1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef __SOUND_CONTROL_H
3 #define __SOUND_CONTROL_H
6 * Header file for control interface
7 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
10 #include <linux/wait.h>
11 #include <linux/nospec.h>
12 #include <sound/asound.h>
14 #define snd_kcontrol_chip(kcontrol) ((kcontrol)->private_data)
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 */
23 unsigned int __user
*tlv
);
25 /* internal flag for skipping validations */
26 #ifdef CONFIG_SND_CTL_VALIDATION
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)
31 #define SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK 0
32 #define snd_ctl_skip_validation(info) true
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 */
42 SNDRV_CTL_TLV_OP_READ
= 0,
43 SNDRV_CTL_TLV_OP_WRITE
= 1,
44 SNDRV_CTL_TLV_OP_CMD
= -1,
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
;
59 snd_kcontrol_tlv_rw_t
*c
;
60 const unsigned int *p
;
62 unsigned long private_value
;
65 struct snd_kcontrol_volatile
{
66 struct snd_ctl_file
*owner
; /* locked */
67 unsigned int access
; /* access rights */
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
;
78 snd_kcontrol_tlv_rw_t
*c
;
79 const unsigned int *p
;
81 unsigned long private_value
;
83 void (*private_free
)(struct snd_kcontrol
*kcontrol
);
84 struct snd_kcontrol_volatile vd
[]; /* volatile data */
87 #define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list)
89 struct snd_kctl_event
{
90 struct list_head list
; /* list of events */
91 struct snd_ctl_elem_id id
;
95 #define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)
101 SND_CTL_SUBDEV_RAWMIDI
,
102 SND_CTL_SUBDEV_ITEMS
,
105 struct snd_ctl_file
{
106 struct list_head list
; /* list of all control files */
107 struct snd_card
*card
;
109 int preferred_subdevice
[SND_CTL_SUBDEV_ITEMS
];
110 wait_queue_head_t change_sleep
;
111 spinlock_t read_lock
;
112 struct fasync_struct
*fasync
;
113 int subscribed
; /* read interface is activated */
114 struct list_head events
; /* waiting events for read */
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
);
125 #define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list)
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
);
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
);
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 int snd_ctl_activate_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
, int active
);
142 struct snd_kcontrol
*snd_ctl_find_numid(struct snd_card
* card
, unsigned int numid
);
143 struct snd_kcontrol
*snd_ctl_find_id(struct snd_card
* card
, struct snd_ctl_elem_id
*id
);
145 int snd_ctl_create(struct snd_card
*card
);
147 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
);
148 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
);
150 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn
);
151 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn
);
153 #define snd_ctl_register_ioctl_compat(fcn)
154 #define snd_ctl_unregister_ioctl_compat(fcn)
157 int snd_ctl_request_layer(const char *module_name
);
158 void snd_ctl_register_layer(struct snd_ctl_layer_ops
*lops
);
159 void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops
*lops
);
161 int snd_ctl_get_preferred_subdevice(struct snd_card
*card
, int type
);
163 static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol
*kctl
, struct snd_ctl_elem_id
*id
)
165 unsigned int ioff
= id
->numid
- kctl
->id
.numid
;
166 return array_index_nospec(ioff
, kctl
->count
);
169 static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol
*kctl
, struct snd_ctl_elem_id
*id
)
171 unsigned int ioff
= id
->index
- kctl
->id
.index
;
172 return array_index_nospec(ioff
, kctl
->count
);
175 static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol
*kctl
, struct snd_ctl_elem_id
*id
)
178 return snd_ctl_get_ioffnum(kctl
, id
);
180 return snd_ctl_get_ioffidx(kctl
, id
);
184 static inline struct snd_ctl_elem_id
*snd_ctl_build_ioff(struct snd_ctl_elem_id
*dst_id
,
185 struct snd_kcontrol
*src_kctl
,
188 *dst_id
= src_kctl
->id
;
189 dst_id
->index
+= offset
;
190 dst_id
->numid
+= offset
;
195 * Frequently used control callbacks/helpers
197 int snd_ctl_boolean_mono_info(struct snd_kcontrol
*kcontrol
,
198 struct snd_ctl_elem_info
*uinfo
);
199 int snd_ctl_boolean_stereo_info(struct snd_kcontrol
*kcontrol
,
200 struct snd_ctl_elem_info
*uinfo
);
201 int snd_ctl_enum_info(struct snd_ctl_elem_info
*info
, unsigned int channels
,
202 unsigned int items
, const char *const names
[]);
205 * virtual master control
207 struct snd_kcontrol
*snd_ctl_make_virtual_master(char *name
,
208 const unsigned int *tlv
);
209 int _snd_ctl_add_follower(struct snd_kcontrol
*master
,
210 struct snd_kcontrol
*follower
,
212 /* optional flags for follower */
213 #define SND_CTL_FOLLOWER_NEED_UPDATE (1 << 0)
216 * snd_ctl_add_follower - Add a virtual follower control
217 * @master: vmaster element
218 * @follower: follower element to add
220 * Add a virtual follower control to the given master element created via
221 * snd_ctl_create_virtual_master() beforehand.
223 * All followers must be the same type (returning the same information
224 * via info callback). The function doesn't check it, so it's your
227 * Also, some additional limitations:
228 * at most two channels,
229 * logarithmic volume control (dB level) thus no linear volume,
230 * master can only attenuate the volume without gain
232 * Return: Zero if successful or a negative error code.
235 snd_ctl_add_follower(struct snd_kcontrol
*master
, struct snd_kcontrol
*follower
)
237 return _snd_ctl_add_follower(master
, follower
, 0);
241 * snd_ctl_add_follower_uncached - Add a virtual follower control
242 * @master: vmaster element
243 * @follower: follower element to add
245 * Add a virtual follower control to the given master.
246 * Unlike snd_ctl_add_follower(), the element added via this function
247 * is supposed to have volatile values, and get callback is called
248 * at each time queried from the master.
250 * When the control peeks the hardware values directly and the value
251 * can be changed by other means than the put callback of the element,
252 * this function should be used to keep the value always up-to-date.
254 * Return: Zero if successful or a negative error code.
257 snd_ctl_add_follower_uncached(struct snd_kcontrol
*master
,
258 struct snd_kcontrol
*follower
)
260 return _snd_ctl_add_follower(master
, follower
, SND_CTL_FOLLOWER_NEED_UPDATE
);
263 int snd_ctl_add_vmaster_hook(struct snd_kcontrol
*kctl
,
264 void (*hook
)(void *private_data
, int),
266 void snd_ctl_sync_vmaster(struct snd_kcontrol
*kctl
, bool hook_only
);
267 #define snd_ctl_sync_vmaster_hook(kctl) snd_ctl_sync_vmaster(kctl, true)
268 int snd_ctl_apply_vmaster_followers(struct snd_kcontrol
*kctl
,
269 int (*func
)(struct snd_kcontrol
*vfollower
,
270 struct snd_kcontrol
*follower
,
275 * Control LED trigger layer
277 #define SND_CTL_LAYER_MODULE_LED "snd-ctl-led"
279 #if IS_MODULE(CONFIG_SND_CTL_LED)
280 static inline int snd_ctl_led_request(void) { return snd_ctl_request_layer(SND_CTL_LAYER_MODULE_LED
); }
282 static inline int snd_ctl_led_request(void) { return 0; }
286 * Helper functions for jack-detection controls
288 struct snd_kcontrol
*
289 snd_kctl_jack_new(const char *name
, struct snd_card
*card
);
290 void snd_kctl_jack_report(struct snd_card
*card
,
291 struct snd_kcontrol
*kctl
, bool status
);
293 #endif /* __SOUND_CONTROL_H */