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_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
41enum {
42	SNDRV_CTL_TLV_OP_READ = 0,
43	SNDRV_CTL_TLV_OP_WRITE = 1,
44	SNDRV_CTL_TLV_OP_CMD = -1,
45};
46
47struct 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
65struct snd_kcontrol_volatile {
66	struct snd_ctl_file *owner;	/* locked */
67	unsigned int access;	/* access rights */
68};
69
70struct 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
89struct 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
97struct pid;
98
99enum {
100	SND_CTL_SUBDEV_PCM,
101	SND_CTL_SUBDEV_RAWMIDI,
102	SND_CTL_SUBDEV_ITEMS,
103};
104
105struct 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
117struct 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
127typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card,
128				      struct snd_ctl_file * control,
129				      unsigned int cmd, unsigned long arg);
130
131void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id);
132void snd_ctl_notify_one(struct snd_card * card, unsigned int mask, struct snd_kcontrol * kctl, unsigned int ioff);
133
134struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data);
135void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
136int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
137int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
138int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace);
139int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
140int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
141void snd_ctl_rename(struct snd_card *card, struct snd_kcontrol *kctl, const char *name);
142int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id, int active);
143struct snd_kcontrol *snd_ctl_find_numid_locked(struct snd_card *card, unsigned int numid);
144struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid);
145struct snd_kcontrol *snd_ctl_find_id_locked(struct snd_card *card, const struct snd_ctl_elem_id *id);
146struct 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 */
160static inline struct snd_kcontrol *
161snd_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
170int snd_ctl_create(struct snd_card *card);
171
172int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn);
173int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn);
174#ifdef CONFIG_COMPAT
175int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn);
176int 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
182int snd_ctl_request_layer(const char *module_name);
183void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops);
184void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops);
185
186int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type);
187
188static 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
194static 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
200static 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
209static 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 */
222int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
223			      struct snd_ctl_elem_info *uinfo);
224int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
225				struct snd_ctl_elem_info *uinfo);
226int 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 */
232struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
233						 const unsigned int *tlv);
234int _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 */
259static inline int
260snd_ctl_add_follower(struct snd_kcontrol *master, struct snd_kcontrol *follower)
261{
262	return _snd_ctl_add_follower(master, follower, 0);
263}
264
265int 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 */
284static inline int
285snd_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
291int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl,
292			     void (*hook)(void *private_data, int),
293			     void *private_data);
294void 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)
296int 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)
308static inline int snd_ctl_led_request(void) { return snd_ctl_request_layer(SND_CTL_LAYER_MODULE_LED); }
309#else
310static inline int snd_ctl_led_request(void) { return 0; }
311#endif
312
313/*
314 * Helper functions for jack-detection controls
315 */
316struct snd_kcontrol *
317snd_kctl_jack_new(const char *name, struct snd_card *card);
318void snd_kctl_jack_report(struct snd_card *card,
319			  struct snd_kcontrol *kctl, bool status);
320
321#endif	/* __SOUND_CONTROL_H */
322