xref: /openbmc/linux/include/sound/control.h (revision cd238eff)
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 
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 
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 
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 
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
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
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