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
16struct snd_kcontrol;
17typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo);
18typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
19typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
20typedef 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_VALIDATION
27#define SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK	(1 << 27)
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
35enum {
36	SNDRV_CTL_TLV_OP_READ = 0,
37	SNDRV_CTL_TLV_OP_WRITE = 1,
38	SNDRV_CTL_TLV_OP_CMD = -1,
39};
40
41struct snd_kcontrol_new {
42	snd_ctl_elem_iface_t iface;	/* interface identifier */
43	unsigned int device;		/* device/client number */
44	unsigned int subdevice;		/* subdevice (substream) number */
45	const char *name;		/* ASCII name of item */
46	unsigned int index;		/* index of item */
47	unsigned int access;		/* access rights */
48	unsigned int count;		/* count of same elements */
49	snd_kcontrol_info_t *info;
50	snd_kcontrol_get_t *get;
51	snd_kcontrol_put_t *put;
52	union {
53		snd_kcontrol_tlv_rw_t *c;
54		const unsigned int *p;
55	} tlv;
56	unsigned long private_value;
57};
58
59struct snd_kcontrol_volatile {
60	struct snd_ctl_file *owner;	/* locked */
61	unsigned int access;	/* access rights */
62};
63
64struct snd_kcontrol {
65	struct list_head list;		/* list of controls */
66	struct snd_ctl_elem_id id;
67	unsigned int count;		/* count of same elements */
68	snd_kcontrol_info_t *info;
69	snd_kcontrol_get_t *get;
70	snd_kcontrol_put_t *put;
71	union {
72		snd_kcontrol_tlv_rw_t *c;
73		const unsigned int *p;
74	} tlv;
75	unsigned long private_value;
76	void *private_data;
77	void (*private_free)(struct snd_kcontrol *kcontrol);
78	struct snd_kcontrol_volatile vd[];	/* volatile data */
79};
80
81#define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list)
82
83struct snd_kctl_event {
84	struct list_head list;	/* list of events */
85	struct snd_ctl_elem_id id;
86	unsigned int mask;
87};
88
89#define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)
90
91struct pid;
92
93enum {
94	SND_CTL_SUBDEV_PCM,
95	SND_CTL_SUBDEV_RAWMIDI,
96	SND_CTL_SUBDEV_ITEMS,
97};
98
99struct snd_ctl_file {
100	struct list_head list;		/* list of all control files */
101	struct snd_card *card;
102	struct pid *pid;
103	int preferred_subdevice[SND_CTL_SUBDEV_ITEMS];
104	wait_queue_head_t change_sleep;
105	spinlock_t read_lock;
106	struct snd_fasync *fasync;
107	int subscribed;			/* read interface is activated */
108	struct list_head events;	/* waiting events for read */
109};
110
111#define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list)
112
113typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card,
114				      struct snd_ctl_file * control,
115				      unsigned int cmd, unsigned long arg);
116
117void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id);
118
119struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data);
120void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
121int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
122int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
123int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace);
124int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
125int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
126int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
127			int active);
128struct snd_kcontrol *snd_ctl_find_numid(struct snd_card * card, unsigned int numid);
129struct snd_kcontrol *snd_ctl_find_id(struct snd_card * card, struct snd_ctl_elem_id *id);
130
131int snd_ctl_create(struct snd_card *card);
132
133int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn);
134int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn);
135#ifdef CONFIG_COMPAT
136int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn);
137int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn);
138#else
139#define snd_ctl_register_ioctl_compat(fcn)
140#define snd_ctl_unregister_ioctl_compat(fcn)
141#endif
142
143int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type);
144
145static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
146{
147	unsigned int ioff = id->numid - kctl->id.numid;
148	return array_index_nospec(ioff, kctl->count);
149}
150
151static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
152{
153	unsigned int ioff = id->index - kctl->id.index;
154	return array_index_nospec(ioff, kctl->count);
155}
156
157static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
158{
159	if (id->numid) {
160		return snd_ctl_get_ioffnum(kctl, id);
161	} else {
162		return snd_ctl_get_ioffidx(kctl, id);
163	}
164}
165
166static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id,
167						    struct snd_kcontrol *src_kctl,
168						    unsigned int offset)
169{
170	*dst_id = src_kctl->id;
171	dst_id->index += offset;
172	dst_id->numid += offset;
173	return dst_id;
174}
175
176/*
177 * Frequently used control callbacks/helpers
178 */
179int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
180			      struct snd_ctl_elem_info *uinfo);
181int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
182				struct snd_ctl_elem_info *uinfo);
183int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
184		      unsigned int items, const char *const names[]);
185
186/*
187 * virtual master control
188 */
189struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
190						 const unsigned int *tlv);
191int _snd_ctl_add_follower(struct snd_kcontrol *master,
192			  struct snd_kcontrol *follower,
193			  unsigned int flags);
194/* optional flags for follower */
195#define SND_CTL_FOLLOWER_NEED_UPDATE	(1 << 0)
196
197/**
198 * snd_ctl_add_follower - Add a virtual follower control
199 * @master: vmaster element
200 * @follower: follower element to add
201 *
202 * Add a virtual follower control to the given master element created via
203 * snd_ctl_create_virtual_master() beforehand.
204 *
205 * All followers must be the same type (returning the same information
206 * via info callback).  The function doesn't check it, so it's your
207 * responsibility.
208 *
209 * Also, some additional limitations:
210 * at most two channels,
211 * logarithmic volume control (dB level) thus no linear volume,
212 * master can only attenuate the volume without gain
213 *
214 * Return: Zero if successful or a negative error code.
215 */
216static inline int
217snd_ctl_add_follower(struct snd_kcontrol *master, struct snd_kcontrol *follower)
218{
219	return _snd_ctl_add_follower(master, follower, 0);
220}
221
222/**
223 * snd_ctl_add_follower_uncached - Add a virtual follower control
224 * @master: vmaster element
225 * @follower: follower element to add
226 *
227 * Add a virtual follower control to the given master.
228 * Unlike snd_ctl_add_follower(), the element added via this function
229 * is supposed to have volatile values, and get callback is called
230 * at each time queried from the master.
231 *
232 * When the control peeks the hardware values directly and the value
233 * can be changed by other means than the put callback of the element,
234 * this function should be used to keep the value always up-to-date.
235 *
236 * Return: Zero if successful or a negative error code.
237 */
238static inline int
239snd_ctl_add_follower_uncached(struct snd_kcontrol *master,
240			      struct snd_kcontrol *follower)
241{
242	return _snd_ctl_add_follower(master, follower, SND_CTL_FOLLOWER_NEED_UPDATE);
243}
244
245int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl,
246			     void (*hook)(void *private_data, int),
247			     void *private_data);
248void snd_ctl_sync_vmaster(struct snd_kcontrol *kctl, bool hook_only);
249#define snd_ctl_sync_vmaster_hook(kctl)	snd_ctl_sync_vmaster(kctl, true)
250int snd_ctl_apply_vmaster_followers(struct snd_kcontrol *kctl,
251				    int (*func)(struct snd_kcontrol *vfollower,
252						struct snd_kcontrol *follower,
253						void *arg),
254				    void *arg);
255
256/*
257 * Helper functions for jack-detection controls
258 */
259struct snd_kcontrol *
260snd_kctl_jack_new(const char *name, struct snd_card *card);
261void snd_kctl_jack_report(struct snd_card *card,
262			  struct snd_kcontrol *kctl, bool status);
263
264#endif	/* __SOUND_CONTROL_H */
265