snd_soc_add_card_controls – add an array of controls to a SoC card. Convenience function to add a list of controls. Synopsis int snd_soc_add_card_controls(struct snd_soc_card *soc_card, const struct snd_kcontrol_new *controls, int num_controls); Arguments soc_card SoC card to add controls to controls array of controls to add num_controls number of elements in the array Description Return 0 for…
snd_request_card – try to load the card module Synopsis void snd_request_card(int card); Arguments card the card number Description Tries to load the module “snd-card-X” for the given card number via request_module. Returns immediately if already loaded. Copyright
snd_register_device – Register the ALSA device file for the card Synopsis int snd_register_device(int type, struct snd_card *card, int dev, const struct file_operations *f_ops, void *private_data, struct device *device); Arguments type the device type, SNDRV_DEVICE_TYPE_XXX card the card instance dev the device index f_ops the file operations private_data user pointer for f_ops->open device the device to…
snd_rawmidi_transmit_peek – copy data from the internal buffer Synopsis int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream, unsigned char *buffer, int count); Arguments substream the rawmidi substream buffer the buffer pointer count data size to transfer Description Copies data from the internal output buffer to the given buffer. Call this in the interrupt handler when the midi output is…
snd_rawmidi_transmit_empty – check whether the output buffer is empty Synopsis int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream); Arguments substream the rawmidi substream Return 1 if the internal output buffer is empty, 0 if not. Copyright
snd_rawmidi_transmit_ack – acknowledge the transmission Synopsis int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count); Arguments substream the rawmidi substream count the transferred count Description Advances the hardware pointer for the internal output buffer with the given size and updates the condition. Call after the transmission is finished. Return The advanced size if successful, or a negative error…
snd_rawmidi_transmit – copy from the buffer to the device Synopsis int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream, unsigned char *buffer, int count); Arguments substream the rawmidi substream buffer the buffer pointer count the data size to transfer Description Copies data from the buffer to the device and advances the pointer. Return The copied size if successful, or a…
snd_rawmidi_set_ops – set the rawmidi operators Synopsis void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream, struct snd_rawmidi_ops *ops); Arguments rmidi the rawmidi instance stream the stream direction, SNDRV_RAWMIDI_STREAM_XXX ops the operator table Description Sets the rawmidi operators for the given stream direction. Copyright
snd_rawmidi_receive – receive the input data from the device Synopsis int snd_rawmidi_receive(struct snd_rawmidi_substream *substream, const unsigned char *buffer, int count); Arguments substream the rawmidi substream buffer the buffer pointer count the data size to read Description Reads the data from the internal buffer. Return The size of read data, or a negative error code on…
snd_rawmidi_new – create a rawmidi instance Synopsis int snd_rawmidi_new(struct snd_card *card, char *id, int device, int output_count, int input_count, struct snd_rawmidi **rrawmidi); Arguments card the card instance id the id string device the device index output_count the number of output streams input_count the number of input streams rrawmidi the pointer to store the new rawmidi…
snd_printk – printk wrapper Synopsis snd_printk(fmt, …); Arguments fmt format string … variable arguments Description Works like printk but prints the file and the line of the caller when configured with CONFIG_SND_VERBOSE_PRINTK. Copyright
snd_printdd – debug printk Synopsis snd_printdd(format, …); Arguments format format string … variable arguments Description Works like snd_printk for debugging purposes. Ignored when CONFIG_SND_DEBUG_VERBOSE is not set. Copyright
snd_printd_ratelimit – Synopsis snd_printd_ratelimit(void); Arguments None Copyright
snd_printd – debug printk Synopsis snd_printd(fmt, …); Arguments fmt format string … variable arguments Description Works like snd_printk for debugging purposes. Ignored when CONFIG_SND_DEBUG is not set. Copyright
snd_power_wait – wait until the power-state is changed. Synopsis int snd_power_wait(struct snd_card *card, unsigned int power_state); Arguments card soundcard structure power_state expected power state Description Waits until the power-state is changed. Return Zero if successful, or a negative error code. Note the power lock must be active before call. Copyright
snd_pcm_trigger_done – Mark the master substream Synopsis void snd_pcm_trigger_done(struct snd_pcm_substream *substream, struct snd_pcm_substream *master); Arguments substream the pcm substream instance master the linked master substream Description When multiple substreams of the same card are linked and the hardware supports the single-shot operation, the driver calls this in the loop in snd_pcm_group_for_each_entry for marking the substream…
snd_pcm_suspend_all – trigger SUSPEND to all substreams in the given pcm Synopsis int snd_pcm_suspend_all(struct snd_pcm *pcm); Arguments pcm the PCM instance Description After this call, all streams are changed to SUSPENDED state. Return Zero if successful (or pcm is NULL), or a negative error code. Copyright
snd_pcm_suspend – trigger SUSPEND to all linked streams Synopsis int snd_pcm_suspend(struct snd_pcm_substream *substream); Arguments substream the PCM substream Description After this call, all streams are changed to SUSPENDED state. Return Zero if successful (or substream is NULL), or a negative error code. Copyright
snd_pcm_substream_to_dma_direction – Get dma_transfer_direction for a PCM substream Synopsis enum dma_transfer_direction snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream * substream); Arguments substream PCM substream Copyright
snd_pcm_stream_unlock_irqrestore – Unlock the PCM stream Synopsis void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream, unsigned long flags); Arguments substream PCM substream flags irq flags Description This is a counter-part of snd_pcm_stream_lock_irqsave. Copyright