snd_ctl_replace – replace the control instance of the card Synopsis int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace); Arguments card the card instance kcontrol the control instance to replace add_on_replace add the control if not already added Description Replaces the given control. If the given control does not exist and the add_on_replace flag is…
snd_ctl_rename_id – replace the id of a control on the card Synopsis int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id); Arguments card the card instance src_id the old id dst_id the new id Description Finds the control with the old id from the card, and replaces the id with the new one. Return…
snd_ctl_remove_id – remove the control of the given id and release it Synopsis int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id); Arguments card the card instance id the control id to remove Description Finds the control instance with the given id, removes it from the card list and releases it. Return 0 if successful, or a…
snd_ctl_remove – remove the control from the card and release it Synopsis int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol); Arguments card the card instance kcontrol the control instance to remove Description Removes the control from the card and then releases the instance. You don’t need to call snd_ctl_free_one. You must be in the write lock…
snd_ctl_register_ioctl_compat – register the device-specific 32bit compat control-ioctls Synopsis int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn); Arguments fcn ioctl callback function Copyright
snd_ctl_register_ioctl – register the device-specific control-ioctls Synopsis int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn); Arguments fcn ioctl callback function Description called from each device manager like pcm.c, hwdep.c, etc. Copyright
snd_ctl_notify – Send notification to user-space for a control change Synopsis void snd_ctl_notify(struct snd_card *card, unsigned int mask, struct snd_ctl_elem_id *id); Arguments card the card to send notification mask the event mask, SNDRV_CTL_EVENT_* id the ctl element id to send notification Description This function adds an event record with the given id and mask, appends…
snd_ctl_new1 – create a control instance from the template Synopsis struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol, void *private_data); Arguments ncontrol the initialization record private_data the private data to set Description Allocates a new struct snd_kcontrol instance and initialize from the given template. When the access field of ncontrol is 0, it’s assumed as READWRITE access….
snd_ctl_make_virtual_master – Create a virtual master control Synopsis struct snd_kcontrol *snd_ctl_make_virtual_master(char *name, const unsigned int *tlv); Arguments name name string of the control element to create tlv optional TLV int array for dB information Description Creates a virtual master control with the given name string. After creating a vmaster element, you can add the slave…
snd_ctl_free_one – release the control instance Synopsis void snd_ctl_free_one(struct snd_kcontrol *kcontrol); Arguments kcontrol the control instance Description Releases the control instance created via snd_ctl_new or snd_ctl_new1. Don’t call this after the control was added to the card. Copyright
snd_ctl_find_numid – find the control instance with the given number-id Synopsis struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid); Arguments card the card instance numid the number-id to search Description Finds the control instance with the given number-id from the card. The caller must down card->controls_rwsem before calling this function (if the race condition can…
snd_ctl_find_id – find the control instance with the given id Synopsis struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, struct snd_ctl_elem_id *id); Arguments card the card instance id the id to search Description Finds the control instance with the given id from the card. The caller must down card->controls_rwsem before calling this function (if the race condition can…
snd_ctl_enum_info – fills the info structure for an enumerated control Synopsis int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels, unsigned int items, const char *const names[]); Arguments info the structure to be filled channels the number of the control’s channels; often one items the number of control values; also the size of names names[] an array…
snd_ctl_boolean_stereo_info – Helper function for a standard boolean info callback with stereo two channels Synopsis int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo); Arguments kcontrol the kcontrol instance uinfo info to store Description This is a function that can be used as info callback for a standard boolean control with stereo two channels. Copyright
snd_ctl_boolean_mono_info – Helper function for a standard boolean info callback with a mono channel Synopsis int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo); Arguments kcontrol the kcontrol instance uinfo info to store Description This is a function that can be used as info callback for a standard boolean control with a single mono channel. Copyright
snd_ctl_add_vmaster_hook – Add a hook to a vmaster control Synopsis int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kcontrol, void (*hook)(void *private_data, int), void *private_data); Arguments kcontrol vmaster kctl element hook the hook function private_data the private_data pointer to be saved Description Adds the given hook to the vmaster control element so that it’s called at each time when the…
snd_ctl_add_slave_uncached – Add a virtual slave control Synopsis int snd_ctl_add_slave_uncached(struct snd_kcontrol *master, struct snd_kcontrol *slave); Arguments master vmaster element slave slave element to add Description Add a virtual slave control to the given master. Unlike snd_ctl_add_slave, the element added via this function is supposed to have volatile values, and get callback is called at each…
snd_ctl_add_slave – Add a virtual slave control Synopsis int snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave); Arguments master vmaster element slave slave element to add Description Add a virtual slave control to the given master element created via snd_ctl_create_virtual_master beforehand. All slaves must be the same type (returning the same information via info callback). The function…
snd_ctl_add – add the control instance to the card Synopsis int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol); Arguments card the card instance kcontrol the control instance to add Description Adds the control instance created via snd_ctl_new or snd_ctl_new1 to the given card. Assigns also an unique numid used for fast search. It frees automatically the…
snd_ctl_activate_id – activate/inactivate the control of the given id Synopsis int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id, int active); Arguments card the card instance id the control id to activate/inactivate active non-zero to activate Description Finds the control instance with the given id, and activate or inactivate the control together with notification, if changed. The…