include/sound/control.h

   1 #ifndef __SOUND_CONTROL_H
   2 #define __SOUND_CONTROL_H
   3
   4 /*
   5  *  Header file for control interface
   6  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   7  *
   8  *
   9  *   This program is free software; you can redistribute it and/or modify
  10  *   it under the terms of the GNU General Public License as published by
  11  *   the Free Software Foundation; either version 2 of the License, or
  12  *   (at your option) any later version.
  13  *
  14  *   This program is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with this program; if not, write to the Free Software
  21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  22  *
  23  */
  24
  25 #include <sound/asound.h>
  26
  27 #define snd_kcontrol_chip(kcontrol) ((kcontrol)->private_data)
  28
  29 struct snd_kcontrol;
  30 typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo);
  31 typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
  32 typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
  33 typedef int (snd_kcontrol_tlv_rw_t)(struct snd_kcontrol *kcontrol,
  34                                     int op_flag, /* 0=read,1=write,-1=command */
  35                                     unsigned int size,
  36                                     unsigned int __user *tlv);
  37
  38
  39 struct snd_kcontrol_new {
  40         snd_ctl_elem_iface_t iface;     /* interface identifier */
  41         unsigned int device;            /* device/client number */
  42         unsigned int subdevice;         /* subdevice (substream) number */
  43         unsigned char *name;            /* ASCII name of item */
  44         unsigned int index;             /* index of item */
  45         unsigned int access;            /* access rights */
  46         unsigned int count;             /* count of same elements */
  47         snd_kcontrol_info_t *info;
  48         snd_kcontrol_get_t *get;
  49         snd_kcontrol_put_t *put;
  50         union {
  51                 snd_kcontrol_tlv_rw_t *c;
  52                 const unsigned int *p;
  53         } tlv;
  54         unsigned long private_value;
  55 };
  56
  57 struct snd_kcontrol_volatile {
  58         struct snd_ctl_file *owner;     /* locked */
  59         unsigned int access;    /* access rights */
  60 };
  61
  62 struct snd_kcontrol {
  63         struct list_head list;          /* list of controls */
  64         struct snd_ctl_elem_id id;
  65         unsigned int count;             /* count of same elements */
  66         snd_kcontrol_info_t *info;
  67         snd_kcontrol_get_t *get;
  68         snd_kcontrol_put_t *put;
  69         union {
  70                 snd_kcontrol_tlv_rw_t *c;
  71                 const unsigned int *p;
  72         } tlv;
  73         unsigned long private_value;
  74         void *private_data;
  75         void (*private_free)(struct snd_kcontrol *kcontrol);
  76         struct snd_kcontrol_volatile vd[0];     /* volatile data */
  77 };
  78
  79 #define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list)
  80
  81 struct snd_kctl_event {
  82         struct list_head list;  /* list of events */
  83         struct snd_ctl_elem_id id;
  84         unsigned int mask;
  85 };
  86
  87 #define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)
  88
  89 struct pid;
  90
  91 struct snd_ctl_file {
  92         struct list_head list;          /* list of all control files */
  93         struct snd_card *card;
  94         struct pid *pid;
  95         int prefer_pcm_subdevice;
  96         int prefer_rawmidi_subdevice;
  97         wait_queue_head_t change_sleep;
  98         spinlock_t read_lock;
  99         struct fasync_struct *fasync;
 100         int subscribed;                 /* read interface is activated */
 101         struct list_head events;        /* waiting events for read */
 102 };
 103
 104 #define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list)
 105
 106 typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card,
 107                                       struct snd_ctl_file * control,
 108                                       unsigned int cmd, unsigned long arg);
 109
 110 void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id);
 111
 112 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data);
 113 void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
 114 int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
 115 int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
 116 int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
 117 int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
 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 static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
 134 {
 135         return id->numid - kctl->id.numid;
 136 }
 137
 138 static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
 139 {
 140         return id->index - kctl->id.index;
 141 }
 142
 143 static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
 144 {
 145         if (id->numid) {
 146                 return snd_ctl_get_ioffnum(kctl, id);
 147         } else {
 148                 return snd_ctl_get_ioffidx(kctl, id);
 149         }
 150 }
 151
 152 static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id,
 153                                                     struct snd_kcontrol *src_kctl,
 154                                                     unsigned int offset)
 155 {
 156         *dst_id = src_kctl->id;
 157         dst_id->index += offset;
 158         dst_id->numid += offset;
 159         return dst_id;
 160 }
 161
 162 /*
 163  * Frequently used control callbacks/helpers
 164  */
 165 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
 166                               struct snd_ctl_elem_info *uinfo);
 167 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
 168                                 struct snd_ctl_elem_info *uinfo);
 169 int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
 170                       unsigned int items, const char *const names[]);
 171
 172 /*
 173  * virtual master control
 174  */
 175 struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
 176                                                  const unsigned int *tlv);
 177 int _snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave,
 178                        unsigned int flags);
 179 /* optional flags for slave */
 180 #define SND_CTL_SLAVE_NEED_UPDATE       (1 << 0)
 181
 182 /**
 183  * snd_ctl_add_slave - Add a virtual slave control
 184  * @master: vmaster element
 185  * @slave: slave element to add
 186  *
 187  * Add a virtual slave control to the given master element created via
 188  * snd_ctl_create_virtual_master() beforehand.
 189  * Returns zero if successful or a negative error code.
 190  *
 191  * All slaves must be the same type (returning the same information
 192  * via info callback).  The fucntion doesn't check it, so it's your
 193  * responsibility.
 194  *
 195  * Also, some additional limitations:
 196  * at most two channels,
 197  * logarithmic volume control (dB level) thus no linear volume,
 198  * master can only attenuate the volume without gain
 199  */
 200 static inline int
 201 snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave)
 202 {
 203         return _snd_ctl_add_slave(master, slave, 0);
 204 }
 205
 206 /**
 207  * snd_ctl_add_slave_uncached - Add a virtual slave control
 208  * @master: vmaster element
 209  * @slave: slave element to add
 210  *
 211  * Add a virtual slave control to the given master.
 212  * Unlike snd_ctl_add_slave(), the element added via this function
 213  * is supposed to have volatile values, and get callback is called
 214  * at each time quried from the master.
 215  *
 216  * When the control peeks the hardware values directly and the value
 217  * can be changed by other means than the put callback of the element,
 218  * this function should be used to keep the value always up-to-date.
 219  */
 220 static inline int
 221 snd_ctl_add_slave_uncached(struct snd_kcontrol *master,
 222                            struct snd_kcontrol *slave)
 223 {
 224         return _snd_ctl_add_slave(master, slave, SND_CTL_SLAVE_NEED_UPDATE);
 225 }
 226
 227 #endif  /* __SOUND_CONTROL_H */