snd_card_free – frees given soundcard structure Synopsis int snd_card_free(struct snd_card *card); Arguments card soundcard structure Description This function releases the soundcard structure and the all assigned devices automatically. That is, you don’t have to release the devices by yourself. This function waits until the all resources are properly released. Return Zero. Frees all associated devices…
snd_card_file_remove – remove the file from the file list Synopsis int snd_card_file_remove(struct snd_card *card, struct file *file); Arguments card soundcard structure file file pointer Description This function removes the file formerly added to the card via snd_card_file_add function. If all files are removed and snd_card_free_when_closed was called beforehand, it processes the pending release of resources….
snd_card_file_add – add the file to the file list of the card Synopsis int snd_card_file_add(struct snd_card *card, struct file *file); Arguments card soundcard structure file file pointer Description This function adds the file to the file linked-list of the card. This linked-list is used to keep tracking the connection state, and to avoid the release…
snd_card_disconnect – disconnect all APIs from the file-operations (user space) Synopsis int snd_card_disconnect(struct snd_card *card); Arguments card soundcard structure Description Disconnects all APIs from the file-operations (user space). Return Zero, otherwise a negative error code. Note The current implementation replaces all active file->f_op with special dummy file operations (they do nothing except release). Copyright
snd_card_add_dev_attr – Append a new sysfs attribute group to card Synopsis int snd_card_add_dev_attr(struct snd_card *card, const struct attribute_group *group); Arguments card card instance group attribute group to append Copyright
snd_ac97_write_cache – write a value on the given register and update the cache Synopsis void snd_ac97_write_cache(struct snd_ac97 *ac97, unsigned short reg, unsigned short value); Arguments ac97 the ac97 instance reg the register to change value the value to set Description Writes a value on the given register and updates the register cache. The cached values…
snd_ac97_write – write a value on the given register Synopsis void snd_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short value); Arguments ac97 the ac97 instance reg the register to change value the value to set Description Writes a value on the given register. This will invoke the write callback directly after the register check. This…
snd_ac97_update_power – update the powerdown register Synopsis int snd_ac97_update_power(struct snd_ac97 *ac97, int reg, int powerup); Arguments ac97 the codec instance reg the rate register, e.g. AC97_PCM_FRONT_DAC_RATE powerup non-zero when power up the part Description Update the AC97 powerdown register bits of the given part. Return Zero. Copyright
snd_ac97_update_bits – update the bits on the given register Synopsis int snd_ac97_update_bits(struct snd_ac97 *ac97, unsigned short reg, unsigned short mask, unsigned short value); Arguments ac97 the ac97 instance reg the register to change mask the bit-mask to change value the value to set Description Updates the masked-bits on the given register only when the value…
snd_ac97_update – update the value on the given register Synopsis int snd_ac97_update(struct snd_ac97 *ac97, unsigned short reg, unsigned short value); Arguments ac97 the ac97 instance reg the register to change value the value to set Description Compares the value with the register cache and updates the value only when the value is changed. Return 1…
snd_ac97_tune_hardware – tune up the hardware Synopsis int snd_ac97_tune_hardware(struct snd_ac97 *ac97, const struct ac97_quirk *quirk, const char *override); Arguments ac97 the ac97 instance quirk quirk list override explicit quirk value (overrides the list if non-NULL) Description Do some workaround for each pci device, such as renaming of the headphone (true line-out) control as “Master”. The…
snd_ac97_suspend – General suspend function for AC97 codec Synopsis void snd_ac97_suspend(struct snd_ac97 *ac97); Arguments ac97 the ac97 instance Description Suspends the codec, power down the chip. Copyright
snd_ac97_set_rate – change the rate of the given input/output. Synopsis int snd_ac97_set_rate(struct snd_ac97 *ac97, int reg, unsigned int rate); Arguments ac97 the ac97 instance reg the register to change rate the sample rate to set Description Changes the rate of the given input/output on the codec. If the codec doesn’t support VAR, the rate must…
snd_ac97_resume – General resume function for AC97 codec Synopsis void snd_ac97_resume(struct snd_ac97 *ac97); Arguments ac97 the ac97 instance Description Do the standard resume procedure, power up and restoring the old register values. Copyright
snd_ac97_read – read a value from the given register Synopsis unsigned short snd_ac97_read(struct snd_ac97 *ac97, unsigned short reg); Arguments ac97 the ac97 instance reg the register to read Description Reads a value from the given register. This will invoke the read callback directly after the register check. Return The read value. Copyright
snd_ac97_pcm_open – opens the given AC97 pcm Synopsis int snd_ac97_pcm_open(struct ac97_pcm *pcm, unsigned int rate, enum ac97_pcm_cfg cfg, unsigned short slots); Arguments pcm the ac97 pcm instance rate rate in Hz, if codec does not support VRA, this value must be 48000Hz cfg output stream characteristics slots a subset of allocated slots (snd_ac97_pcm_assign) for this…
snd_ac97_pcm_double_rate_rules – set double rate constraints Synopsis int snd_ac97_pcm_double_rate_rules(struct snd_pcm_runtime *runtime); Arguments runtime the runtime of the ac97 front playback pcm Description Installs the hardware constraint rules to prevent using double rates and more than two channels at the same time. Return Zero if successful, or a negative error code on failure. Copyright
snd_ac97_pcm_close – closes the given AC97 pcm Synopsis int snd_ac97_pcm_close(struct ac97_pcm *pcm); Arguments pcm the ac97 pcm instance Description It frees the locked AC97 slots. Return Zero. Copyright
snd_ac97_pcm_assign – assign AC97 slots to given PCM streams Synopsis int snd_ac97_pcm_assign(struct snd_ac97_bus *bus, unsigned short pcms_count, const struct ac97_pcm *pcms); Arguments bus the ac97 bus instance pcms_count count of PCMs to be assigned pcms PCMs to be assigned Description It assigns available AC97 slots for given PCMs. If none or only some slots are…
snd_ac97_mixer – create an Codec97 component Synopsis int snd_ac97_mixer(struct snd_ac97_bus *bus, struct snd_ac97_template *template, struct snd_ac97 **rac97); Arguments bus the AC97 bus which codec is attached to template the template of ac97, including index, callbacks and the private data. rac97 the pointer to store the new ac97 instance. Description Creates an Codec97 component. An struct…