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 enum {
26 SNDRV_CTL_TLV_OP_READ = 0,
27 SNDRV_CTL_TLV_OP_WRITE = 1,
28 SNDRV_CTL_TLV_OP_CMD = -1,
29 };
30
31 struct snd_kcontrol_new {
32 snd_ctl_elem_iface_t iface; /* interface identifier */
33 unsigned int device; /* device/client number */
34 unsigned int subdevice; /* subdevice (substream) number */
35 const unsigned char *name; /* ASCII name of item */
36 unsigned int index; /* index of item */
37 unsigned int access; /* access rights */
38 unsigned int count; /* count of same elements */
39 snd_kcontrol_info_t *info;
40 snd_kcontrol_get_t *get;
41 snd_kcontrol_put_t *put;
42 union {
43 snd_kcontrol_tlv_rw_t *c;
44 const unsigned int *p;
45 } tlv;
46 unsigned long private_value;
47 };
48
49 struct snd_kcontrol_volatile {
50 struct snd_ctl_file *owner; /* locked */
51 unsigned int access; /* access rights */
52 };
53
54 struct snd_kcontrol {
55 struct list_head list; /* list of controls */
56 struct snd_ctl_elem_id id;
57 unsigned int count; /* count of same elements */
58 snd_kcontrol_info_t *info;
59 snd_kcontrol_get_t *get;
60 snd_kcontrol_put_t *put;
61 union {
62 snd_kcontrol_tlv_rw_t *c;
63 const unsigned int *p;
64 } tlv;
65 unsigned long private_value;
66 void *private_data;
67 void (*private_free)(struct snd_kcontrol *kcontrol);
68 struct snd_kcontrol_volatile vd[0]; /* volatile data */
69 };
70
71 #define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list)
72
73 struct snd_kctl_event {
74 struct list_head list; /* list of events */
75 struct snd_ctl_elem_id id;
76 unsigned int mask;
77 };
78
79 #define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)
80
81 struct pid;
82
83 enum {
84 SND_CTL_SUBDEV_PCM,
85 SND_CTL_SUBDEV_RAWMIDI,
86 SND_CTL_SUBDEV_ITEMS,
87 };
88
89 struct snd_ctl_file {
90 struct list_head list; /* list of all control files */
91 struct snd_card *card;
92 struct pid *pid;
93 int preferred_subdevice[SND_CTL_SUBDEV_ITEMS];
94 wait_queue_head_t change_sleep;
95 spinlock_t read_lock;
96 struct fasync_struct *fasync;
97 int subscribed; /* read interface is activated */
98 struct list_head events; /* waiting events for read */
99 };
100
101 #define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list)
102
103 typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card,
104 struct snd_ctl_file * control,
105 unsigned int cmd, unsigned long arg);
106
107 void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id);
108
109 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data);
110 void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
111 int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
112 int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
113 int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace);
114 int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
115 int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
116 int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
117 int active);
118 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card * card, unsigned int numid);
119 struct snd_kcontrol *snd_ctl_find_id(struct snd_card * card, struct snd_ctl_elem_id *id);
120
121 int snd_ctl_create(struct snd_card *card);
122
123 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn);
124 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn);
125 #ifdef CONFIG_COMPAT
126 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn);
127 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn);
128 #else
129 #define snd_ctl_register_ioctl_compat(fcn)
130 #define snd_ctl_unregister_ioctl_compat(fcn)
131 #endif
132
133 int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type);
134
snd_ctl_get_ioffnum(struct snd_kcontrol * kctl,struct snd_ctl_elem_id * id)135 static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
136 {
137 unsigned int ioff = id->numid - kctl->id.numid;
138 return array_index_nospec(ioff, kctl->count);
139 }
140
snd_ctl_get_ioffidx(struct snd_kcontrol * kctl,struct snd_ctl_elem_id * id)141 static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
142 {
143 unsigned int ioff = id->index - kctl->id.index;
144 return array_index_nospec(ioff, kctl->count);
145 }
146
snd_ctl_get_ioff(struct snd_kcontrol * kctl,struct snd_ctl_elem_id * id)147 static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
148 {
149 if (id->numid) {
150 return snd_ctl_get_ioffnum(kctl, id);
151 } else {
152 return snd_ctl_get_ioffidx(kctl, id);
153 }
154 }
155
snd_ctl_build_ioff(struct snd_ctl_elem_id * dst_id,struct snd_kcontrol * src_kctl,unsigned int offset)156 static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id,
157 struct snd_kcontrol *src_kctl,
158 unsigned int offset)
159 {
160 *dst_id = src_kctl->id;
161 dst_id->index += offset;
162 dst_id->numid += offset;
163 return dst_id;
164 }
165
166 /*
167 * Frequently used control callbacks/helpers
168 */
169 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
170 struct snd_ctl_elem_info *uinfo);
171 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
172 struct snd_ctl_elem_info *uinfo);
173 int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
174 unsigned int items, const char *const names[]);
175
176 /*
177 * virtual master control
178 */
179 struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
180 const unsigned int *tlv);
181 int _snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave,
182 unsigned int flags);
183 /* optional flags for slave */
184 #define SND_CTL_SLAVE_NEED_UPDATE (1 << 0)
185
186 /**
187 * snd_ctl_add_slave - Add a virtual slave control
188 * @master: vmaster element
189 * @slave: slave element to add
190 *
191 * Add a virtual slave control to the given master element created via
192 * snd_ctl_create_virtual_master() beforehand.
193 *
194 * All slaves must be the same type (returning the same information
195 * via info callback). The function doesn't check it, so it's your
196 * responsibility.
197 *
198 * Also, some additional limitations:
199 * at most two channels,
200 * logarithmic volume control (dB level) thus no linear volume,
201 * master can only attenuate the volume without gain
202 *
203 * Return: Zero if successful or a negative error code.
204 */
205 static inline int
snd_ctl_add_slave(struct snd_kcontrol * master,struct snd_kcontrol * slave)206 snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave)
207 {
208 return _snd_ctl_add_slave(master, slave, 0);
209 }
210
211 /**
212 * snd_ctl_add_slave_uncached - Add a virtual slave control
213 * @master: vmaster element
214 * @slave: slave element to add
215 *
216 * Add a virtual slave control to the given master.
217 * Unlike snd_ctl_add_slave(), the element added via this function
218 * is supposed to have volatile values, and get callback is called
219 * at each time queried from the master.
220 *
221 * When the control peeks the hardware values directly and the value
222 * can be changed by other means than the put callback of the element,
223 * this function should be used to keep the value always up-to-date.
224 *
225 * Return: Zero if successful or a negative error code.
226 */
227 static inline int
snd_ctl_add_slave_uncached(struct snd_kcontrol * master,struct snd_kcontrol * slave)228 snd_ctl_add_slave_uncached(struct snd_kcontrol *master,
229 struct snd_kcontrol *slave)
230 {
231 return _snd_ctl_add_slave(master, slave, SND_CTL_SLAVE_NEED_UPDATE);
232 }
233
234 int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl,
235 void (*hook)(void *private_data, int),
236 void *private_data);
237 void snd_ctl_sync_vmaster(struct snd_kcontrol *kctl, bool hook_only);
238 #define snd_ctl_sync_vmaster_hook(kctl) snd_ctl_sync_vmaster(kctl, true)
239 int snd_ctl_apply_vmaster_slaves(struct snd_kcontrol *kctl,
240 int (*func)(struct snd_kcontrol *vslave,
241 struct snd_kcontrol *slave,
242 void *arg),
243 void *arg);
244
245 /*
246 * Helper functions for jack-detection controls
247 */
248 struct snd_kcontrol *
249 snd_kctl_jack_new(const char *name, struct snd_card *card);
250 void snd_kctl_jack_report(struct snd_card *card,
251 struct snd_kcontrol *kctl, bool status);
252
253 #endif /* __SOUND_CONTROL_H */
254