From b7a28579d2addd0e8e3761318c9dd6bec13900a9 Mon Sep 17 00:00:00 2001 From: Taylor Holberton Date: Sat, 19 Nov 2016 23:45:00 -0500 Subject: added some documentation --- src/mixer.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) (limited to 'src/mixer.c') diff --git a/src/mixer.c b/src/mixer.c index 58bf916..e6f50bb 100644 --- a/src/mixer.c +++ b/src/mixer.c @@ -104,6 +104,7 @@ void mixer_close(struct mixer *mixer) /** Opens a mixer for a given card. * @param card The card to open the mixer for. + * @returns An initialized mixer handle. * @ingroup libtinyalsa-mixer */ struct mixer *mixer_open(unsigned int card) @@ -168,11 +169,21 @@ fail: return 0; } +/** Gets the name of the mixer's card. + * @param mixer An initialized mixer handle. + * @returns The name of the mixer's card. + * @ingroup libtinyalsa-mixer + */ const char *mixer_get_name(struct mixer *mixer) { return (const char *)mixer->card_info.name; } +/** Gets the number of mixer controls for a given mixer. + * @param mixer An initialized mixer handle. + * @returns The number of mixer controls for the given mixer. + * @ingroup libtinyalsa-mixer + */ unsigned int mixer_get_num_ctls(struct mixer *mixer) { if (!mixer) @@ -181,6 +192,12 @@ unsigned int mixer_get_num_ctls(struct mixer *mixer) return mixer->count; } +/** Gets a mixer control handle, by the mixer control's id. + * @param mixer An initialized mixer handle. + * @param id The control's id in the given mixer. + * @returns A handle to the mixer control. + * @ingroup libtinyalsa-mixer + */ struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id) { if (mixer && (id < mixer->count)) @@ -189,11 +206,25 @@ struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id) return NULL; } +/** Gets the first instance of mixer control handle, by the mixer control's name. + * @param mixer An initialized mixer handle. + * @param name The control's name in the given mixer. + * @returns A handle to the mixer control. + * @ingroup libtinyalsa-mixer + */ struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name) { return mixer_get_ctl_by_name_and_index(mixer, name, 0); } +/** Gets an instance of mixer control handle, by the mixer control's name and index. + * For instance, if two controls have the name of 'Volume', then and index of 1 would return the second control. + * @param mixer An initialized mixer handle. + * @param name The control's name in the given mixer. + * @param index The control's index. + * @returns A handle to the mixer control. + * @ingroup libtinyalsa-mixer + */ struct mixer_ctl *mixer_get_ctl_by_name_and_index(struct mixer *mixer, const char *name, unsigned int index) @@ -214,11 +245,22 @@ struct mixer_ctl *mixer_get_ctl_by_name_and_index(struct mixer *mixer, return NULL; } +/** Updates the control's info. + * This is useful for a program that may be idle for a period of time. + * @param ctl An initialized control handle. + * @ingroup libtinyalsa-mixer + */ void mixer_ctl_update(struct mixer_ctl *ctl) { ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_INFO, ctl->info); } +/** Gets the control's ID. + * @param ctl An initialized control handle. + * @returns On success, the control's ID is returned. + * On error, UINT_MAX is returned instead. + * @ingroup libtinyalsa-mixer + */ unsigned int mixer_ctl_get_id(struct mixer_ctl *ctl) { if (!ctl) @@ -230,6 +272,12 @@ unsigned int mixer_ctl_get_id(struct mixer_ctl *ctl) return ctl->info.id.numid - 1; } +/** Gets the name of the control. + * @param ctl An initialized control handle. + * @returns On success, the name of the control. + * On error, NULL. + * @ingroup libtinyalsa-mixer + */ const char *mixer_ctl_get_name(struct mixer_ctl *ctl) { if (!ctl) @@ -238,6 +286,12 @@ const char *mixer_ctl_get_name(struct mixer_ctl *ctl) return (const char *)ctl->info.id.name; } +/** Gets the value type of the control. + * @param ctl An initialized control handle + * @returns On success, the type of mixer control. + * On failure, it returns @ref MIXER_CTL_TYPE_UNKNOWN + * @ingroup libtinyalsa-mixer + */ enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl) { if (!ctl) @@ -254,6 +308,11 @@ enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl) }; } +/** Gets the string that describes the value type of the control. + * @param ctl An initialized control handle + * @returns On success, a string describing type of mixer control. + * @ingroup libtinyalsa-mixer + */ const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl) { if (!ctl) @@ -270,6 +329,11 @@ const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl) }; } +/** Gets the number of values in the control. + * @param ctl An initialized control handle + * @returns The number of values in the mixer control + * @ingroup libtinyalsa-mixer + */ unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl) { if (!ctl) -- cgit v1.2.3