This document is free; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This document is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA snd_card_new snd_card_new create and initialize a soundcard structure struct snd_card * snd_card_new int idx const char * xid struct module * module int extra_size idx card index (address) [0 ... (SNDRV_CARDS-1)] xid card identification (ASCII string) module top level module for locking extra_size allocate this extra size after the main soundcard structure Creates and initializes a soundcard structure. Returns kmallocated snd_card structure. Creates the ALSA control interface (which is blocked until snd_card_register function is called). snd_card_disconnect snd_card_disconnect disconnect all APIs from the file-operations (user space) int snd_card_disconnect struct snd_card * card card soundcard structure Disconnects all APIs from the file-operations (user space). Returns zero, otherwise a negative error code. The current implementation replaces all active file->f_op with special dummy file operations (they do nothing except release). snd_card_register snd_card_register register the soundcard int snd_card_register struct snd_card * card card soundcard structure This function registers all the devices assigned to the soundcard. Until calling this, the ALSA control interface is blocked from the external accesses. Thus, you should call this function at the end of the initialization of the card. Returns zero otherwise a negative error code if the registrain failed. snd_component_add snd_component_add add a component string int snd_component_add struct snd_card * card const char * component card soundcard structure component the component id string This function adds the component id string to the supported list. The component can be referred from the alsa-lib. Returns zero otherwise a negative error code. snd_card_file_add snd_card_file_add add the file to the file list of the card int snd_card_file_add struct snd_card * card struct file * file card soundcard structure file file pointer 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 of busy resources by hotplug. Returns zero or a negative error code. snd_card_file_remove snd_card_file_remove remove the file from the file list int snd_card_file_remove struct snd_card * card struct file * file card soundcard structure file file pointer 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. Returns zero or a negative error code. snd_power_wait snd_power_wait wait until the power-state is changed. int snd_power_wait struct snd_card * card unsigned int power_state card soundcard structure power_state expected power state Waits until the power-state is changed. the power lock must be active before call. snd_device_new snd_device_new create an ALSA device component int snd_device_new struct snd_card * card snd_device_type_t type void * device_data struct snd_device_ops * ops card the card instance type the device type, SNDRV_DEV_XXX device_data the data pointer of this device ops the operator table Creates a new device component for the given data pointer. The device will be assigned to the card and managed together by the card. The data pointer plays a role as the identifier, too, so the pointer address must be unique and unchanged. Returns zero if successful, or a negative error code on failure. snd_device_free snd_device_free release the device from the card int snd_device_free struct snd_card * card void * device_data card the card instance device_data the data pointer to release Removes the device from the list on the card and invokes the callbacks, dev_disconnect and dev_free, corresponding to the state. Then release the device. Returns zero if successful, or a negative error code on failure or if the device not found. snd_device_register snd_device_register register the device int snd_device_register struct snd_card * card void * device_data card the card instance device_data the data pointer to register Registers the device which was already created via snd_device_new. Usually this is called from snd_card_register, but it can be called later if any new devices are created after invocation of snd_card_register. Returns zero if successful, or a negative error code on failure or if the device not found. snd_request_card snd_request_card try to load the card module void snd_request_card int card card the card number Tries to load the module snd-card-X for the given card number via KMOD. Returns immediately if already loaded. snd_lookup_minor_data snd_lookup_minor_data get user data of a registered device void * snd_lookup_minor_data unsigned int minor int type minor the minor number type device type (SNDRV_DEVICE_TYPE_XXX) Checks that a minor device with the specified type is registered, and returns its user data pointer. snd_register_device_for_dev snd_register_device_for_dev Register the ALSA device file for the card int snd_register_device_for_dev int type struct snd_card * card int dev const struct file_operations * f_ops void * private_data const char * name struct device * device 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 name the device file name device the &struct device to link this new device to Registers an ALSA device file for the given card. The operators have to be set in reg parameter. Returns zero if successful, or a negative error code on failure. snd_unregister_device snd_unregister_device unregister the device on the given card int snd_unregister_device int type struct snd_card * card int dev type the device type, SNDRV_DEVICE_TYPE_XXX card the card instance dev the device index Unregisters the device file already registered via snd_register_device. Returns zero if sucecessful, or a negative error code on failure copy_to_user_fromio copy_to_user_fromio copy data from mmio-space to user-space int copy_to_user_fromio void __user * dst const volatile void __iomem * src size_t count dst the destination pointer on user-space src the source pointer on mmio count the data size to copy in bytes Copies the data from mmio-space to user-space. Returns zero if successful, or non-zero on failure. copy_from_user_toio copy_from_user_toio copy data from user-space to mmio-space int copy_from_user_toio volatile void __iomem * dst const void __user * src size_t count dst the destination pointer on mmio-space src the source pointer on user-space count the data size to copy in bytes Copies the data from user-space to mmio-space. Returns zero if successful, or non-zero on failure. snd_malloc_pages snd_malloc_pages allocate pages with the given size void * snd_malloc_pages size_t size gfp_t gfp_flags size the size to allocate in bytes gfp_flags the allocation conditions, GFP_XXX Allocates the physically contiguous pages with the given size. Returns the pointer of the buffer, or NULL if no enoguh memory. snd_free_pages snd_free_pages release the pages void snd_free_pages void * ptr size_t size ptr the buffer pointer to release size the allocated buffer size Releases the buffer allocated via snd_malloc_pages. snd_dma_alloc_pages snd_dma_alloc_pages allocate the buffer area according to the given type int snd_dma_alloc_pages int type struct device * device size_t size struct snd_dma_buffer * dmab type the DMA buffer type device the device pointer size the buffer size to allocate dmab buffer allocation record to store the allocated data Calls the memory-allocator function for the corresponding buffer type. Returns zero if the buffer with the given size is allocated successfuly, other a negative value at error. snd_dma_alloc_pages_fallback snd_dma_alloc_pages_fallback allocate the buffer area according to the given type with fallback int snd_dma_alloc_pages_fallback int type struct device * device size_t size struct snd_dma_buffer * dmab type the DMA buffer type device the device pointer size the buffer size to allocate dmab buffer allocation record to store the allocated data Calls the memory-allocator function for the corresponding buffer type. When no space is left, this function reduces the size and tries to allocate again. The size actually allocated is stored in res_size argument. Returns zero if the buffer with the given size is allocated successfuly, other a negative value at error. snd_dma_free_pages snd_dma_free_pages release the allocated buffer void snd_dma_free_pages struct snd_dma_buffer * dmab dmab the buffer allocation record to release Releases the allocated buffer via snd_dma_alloc_pages. snd_dma_get_reserved_buf snd_dma_get_reserved_buf get the reserved buffer for the given device size_t snd_dma_get_reserved_buf struct snd_dma_buffer * dmab unsigned int id dmab the buffer allocation record to store id the buffer id Looks for the reserved-buffer list and re-uses if the same buffer is found in the list. When the buffer is found, it's removed from the free list. Returns the size of buffer if the buffer is found, or zero if not found. snd_dma_reserve_buf snd_dma_reserve_buf reserve the buffer int snd_dma_reserve_buf struct snd_dma_buffer * dmab unsigned int id dmab the buffer to reserve id the buffer id Reserves the given buffer as a reserved buffer. Returns zero if successful, or a negative code at error. snd_pcm_new_stream snd_pcm_new_stream create a new PCM stream int snd_pcm_new_stream struct snd_pcm * pcm int stream int substream_count pcm the pcm instance stream the stream direction, SNDRV_PCM_STREAM_XXX substream_count the number of substreams Creates a new stream for the pcm. The corresponding stream on the pcm must have been empty before calling this, i.e. zero must be given to the argument of snd_pcm_new. Returns zero if successful, or a negative error code on failure. snd_pcm_new snd_pcm_new create a new PCM instance int snd_pcm_new struct snd_card * card char * id int device int playback_count int capture_count struct snd_pcm ** rpcm card the card instance id the id string device the device index (zero based) playback_count the number of substreams for playback capture_count the number of substreams for capture rpcm the pointer to store the new pcm instance Creates a new PCM instance. The pcm operators have to be set afterwards to the new instance via snd_pcm_set_ops. Returns zero if successful, or a negative error code on failure. snd_pcm_set_ops snd_pcm_set_ops set the PCM operators void snd_pcm_set_ops struct snd_pcm * pcm int direction struct snd_pcm_ops * ops pcm the pcm instance direction stream direction, SNDRV_PCM_STREAM_XXX ops the operator table Sets the given PCM operators to the pcm instance. snd_pcm_set_sync snd_pcm_set_sync set the PCM sync id void snd_pcm_set_sync struct snd_pcm_substream * substream substream the pcm substream Sets the PCM sync identifier for the card. snd_interval_refine snd_interval_refine refine the interval value of configurator int snd_interval_refine struct snd_interval * i const struct snd_interval * v i the interval value to refine v the interval value to refer to Refines the interval value with the reference value. The interval is changed to the range satisfying both intervals. The interval status (min, max, integer, etc.) are evaluated. Returns non-zero if the value is changed, zero if not changed. snd_interval_ratnum snd_interval_ratnum refine the interval value int snd_interval_ratnum struct snd_interval * i unsigned int rats_count struct snd_ratnum * rats unsigned int * nump unsigned int * denp i interval to refine rats_count number of ratnum_t rats ratnum_t array nump pointer to store the resultant numerator denp pointer to store the resultant denominator Returns non-zero if the value is changed, zero if not changed. snd_interval_list snd_interval_list refine the interval value from the list int snd_interval_list struct snd_interval * i unsigned int count unsigned int * list unsigned int mask i the interval value to refine count the number of elements in the list list the value list mask the bit-mask to evaluate Refines the interval value from the list. When mask is non-zero, only the elements corresponding to bit 1 are evaluated. Returns non-zero if the value is changed, zero if not changed. snd_pcm_hw_rule_add snd_pcm_hw_rule_add add the hw-constraint rule int snd_pcm_hw_rule_add struct snd_pcm_runtime * runtime unsigned int cond int var snd_pcm_hw_rule_func_t func void * private int dep ... ... runtime the pcm runtime instance cond condition bits var the variable to evaluate func the evaluation function private the private data pointer passed to function dep the dependent variables ... variable arguments Returns zero if successful, or a negative error code on failure. snd_pcm_hw_constraint_integer snd_pcm_hw_constraint_integer int snd_pcm_hw_constraint_integer struct snd_pcm_runtime * runtime snd_pcm_hw_param_t var runtime PCM runtime instance var hw_params variable to apply the integer constraint Apply the constraint of integer to an interval parameter. snd_pcm_hw_constraint_minmax snd_pcm_hw_constraint_minmax int snd_pcm_hw_constraint_minmax struct snd_pcm_runtime * runtime snd_pcm_hw_param_t var unsigned int min unsigned int max runtime PCM runtime instance var hw_params variable to apply the range min the minimal value max the maximal value Apply the min/max range constraint to an interval parameter. snd_pcm_hw_constraint_list snd_pcm_hw_constraint_list int snd_pcm_hw_constraint_list struct snd_pcm_runtime * runtime unsigned int cond snd_pcm_hw_param_t var struct snd_pcm_hw_constraint_list * l runtime PCM runtime instance cond condition bits var hw_params variable to apply the list constraint l list Apply the list of constraints to an interval parameter. snd_pcm_hw_constraint_ratnums snd_pcm_hw_constraint_ratnums int snd_pcm_hw_constraint_ratnums struct snd_pcm_runtime * runtime unsigned int cond snd_pcm_hw_param_t var struct snd_pcm_hw_constraint_ratnums * r runtime PCM runtime instance cond condition bits var hw_params variable to apply the ratnums constraint r struct snd_ratnums constriants snd_pcm_hw_constraint_ratdens snd_pcm_hw_constraint_ratdens int snd_pcm_hw_constraint_ratdens struct snd_pcm_runtime * runtime unsigned int cond snd_pcm_hw_param_t var struct snd_pcm_hw_constraint_ratdens * r runtime PCM runtime instance cond condition bits var hw_params variable to apply the ratdens constraint r struct snd_ratdens constriants snd_pcm_hw_constraint_msbits snd_pcm_hw_constraint_msbits int snd_pcm_hw_constraint_msbits struct snd_pcm_runtime * runtime unsigned int cond unsigned int width unsigned int msbits runtime PCM runtime instance cond condition bits width sample bits width msbits msbits width snd_pcm_hw_constraint_step snd_pcm_hw_constraint_step int snd_pcm_hw_constraint_step struct snd_pcm_runtime * runtime unsigned int cond snd_pcm_hw_param_t var unsigned long step runtime PCM runtime instance cond condition bits var hw_params variable to apply the step constraint step step size snd_pcm_hw_constraint_pow2 snd_pcm_hw_constraint_pow2 int snd_pcm_hw_constraint_pow2 struct snd_pcm_runtime * runtime unsigned int cond snd_pcm_hw_param_t var runtime PCM runtime instance cond condition bits var hw_params variable to apply the power-of-2 constraint snd_pcm_hw_param_value snd_pcm_hw_param_value int snd_pcm_hw_param_value const struct snd_pcm_hw_params * params snd_pcm_hw_param_t var int * dir params the hw_params instance var parameter to retrieve dir pointer to the direction (-1,0,1) or NULL Return the value for field PAR if it's fixed in configuration space defined by PARAMS. Return -EINVAL otherwise snd_pcm_hw_param_first snd_pcm_hw_param_first int snd_pcm_hw_param_first struct snd_pcm_substream * pcm struct snd_pcm_hw_params * params snd_pcm_hw_param_t var int * dir pcm PCM instance params the hw_params instance var parameter to retrieve dir pointer to the direction (-1,0,1) or NULL Inside configuration space defined by PARAMS remove from PAR all values > minimum. Reduce configuration space accordingly. Return the minimum. snd_pcm_hw_param_last snd_pcm_hw_param_last int snd_pcm_hw_param_last struct snd_pcm_substream * pcm struct snd_pcm_hw_params * params snd_pcm_hw_param_t var int * dir pcm PCM instance params the hw_params instance var parameter to retrieve dir pointer to the direction (-1,0,1) or NULL Inside configuration space defined by PARAMS remove from PAR all values < maximum. Reduce configuration space accordingly. Return the maximum. snd_pcm_lib_ioctl snd_pcm_lib_ioctl a generic PCM ioctl callback int snd_pcm_lib_ioctl struct snd_pcm_substream * substream unsigned int cmd void * arg substream the pcm substream instance cmd ioctl command arg ioctl argument Processes the generic ioctl commands for PCM. Can be passed as the ioctl callback for PCM ops. Returns zero if successful, or a negative error code on failure. snd_pcm_period_elapsed snd_pcm_period_elapsed update the pcm status for the next period void snd_pcm_period_elapsed struct snd_pcm_substream * substream substream the pcm substream instance This function is called from the interrupt handler when the PCM has processed the period size. It will update the current pointer, set up the tick, wake up sleepers, etc. Even if more than one periods have elapsed since the last call, you have to call this only once. snd_pcm_stop snd_pcm_stop int snd_pcm_stop struct snd_pcm_substream * substream int state substream the PCM substream instance state PCM state after stopping the stream Try to stop all running streams in the substream group. The state of each stream is changed to the given value after that unconditionally. snd_pcm_suspend snd_pcm_suspend int snd_pcm_suspend struct snd_pcm_substream * substream substream the PCM substream Trigger SUSPEND to all linked streams. After this call, all streams are changed to SUSPENDED state. snd_pcm_suspend_all snd_pcm_suspend_all int snd_pcm_suspend_all struct snd_pcm * pcm pcm the PCM instance Trigger SUSPEND to all substreams in the given pcm. After this call, all streams are changed to SUSPENDED state. snd_pcm_format_signed snd_pcm_format_signed Check the PCM format is signed linear int snd_pcm_format_signed snd_pcm_format_t format format the format to check Returns 1 if the given PCM format is signed linear, 0 if unsigned linear, and a negative error code for non-linear formats. snd_pcm_format_unsigned snd_pcm_format_unsigned Check the PCM format is unsigned linear int snd_pcm_format_unsigned snd_pcm_format_t format format the format to check Returns 1 if the given PCM format is unsigned linear, 0 if signed linear, and a negative error code for non-linear formats. snd_pcm_format_linear snd_pcm_format_linear Check the PCM format is linear int snd_pcm_format_linear snd_pcm_format_t format format the format to check Returns 1 if the given PCM format is linear, 0 if not. snd_pcm_format_little_endian snd_pcm_format_little_endian Check the PCM format is little-endian int snd_pcm_format_little_endian snd_pcm_format_t format format the format to check Returns 1 if the given PCM format is little-endian, 0 if big-endian, or a negative error code if endian not specified. snd_pcm_format_big_endian snd_pcm_format_big_endian Check the PCM format is big-endian int snd_pcm_format_big_endian snd_pcm_format_t format format the format to check Returns 1 if the given PCM format is big-endian, 0 if little-endian, or a negative error code if endian not specified. snd_pcm_format_width snd_pcm_format_width return the bit-width of the format int snd_pcm_format_width snd_pcm_format_t format format the format to check Returns the bit-width of the format, or a negative error code if unknown format. snd_pcm_format_physical_width snd_pcm_format_physical_width return the physical bit-width of the format int snd_pcm_format_physical_width snd_pcm_format_t format format the format to check Returns the physical bit-width of the format, or a negative error code if unknown format. snd_pcm_format_size snd_pcm_format_size return the byte size of samples on the given format ssize_t snd_pcm_format_size snd_pcm_format_t format size_t samples format the format to check samples -- undescribed -- Returns the byte size of the given samples for the format, or a negative error code if unknown format. snd_pcm_format_silence_64 snd_pcm_format_silence_64 return the silent data in 8 bytes array const unsigned char * snd_pcm_format_silence_64 snd_pcm_format_t format format the format to check Returns the format pattern to fill or NULL if error. snd_pcm_format_set_silence snd_pcm_format_set_silence set the silence data on the buffer int snd_pcm_format_set_silence snd_pcm_format_t format void * data unsigned int samples format the PCM format data the buffer pointer samples the number of samples to set silence Sets the silence data on the buffer for the given samples. Returns zero if successful, or a negative error code on failure. snd_pcm_build_linear_format snd_pcm_build_linear_format return the suitable linear format for the given condition snd_pcm_format_t snd_pcm_build_linear_format int width int unsignd int big_endian width the bit-width unsignd 1 if unsigned, 0 if signed. big_endian 1 if big-endian, 0 if little-endian Returns the suitable linear format for the given condition. snd_pcm_limit_hw_rates snd_pcm_limit_hw_rates determine rate_min/rate_max fields int snd_pcm_limit_hw_rates struct snd_pcm_runtime * runtime runtime the runtime instance Determines the rate_min and rate_max fields from the rates bits of the given runtime->hw. Returns zero if successful. snd_pcm_lib_preallocate_free_for_all snd_pcm_lib_preallocate_free_for_all release all pre-allocated buffers on the pcm int snd_pcm_lib_preallocate_free_for_all struct snd_pcm * pcm pcm the pcm instance Releases all the pre-allocated buffers on the given pcm. Returns zero if successful, or a negative error code on failure. snd_pcm_lib_preallocate_pages snd_pcm_lib_preallocate_pages pre-allocation for the given DMA type int snd_pcm_lib_preallocate_pages struct snd_pcm_substream * substream int type struct device * data size_t size size_t max substream the pcm substream instance type DMA type (SNDRV_DMA_TYPE_*) data DMA type dependant data size the requested pre-allocation size in bytes max the max. allowed pre-allocation size Do pre-allocation for the given DMA buffer type. When substream->dma_buf_id is set, the function tries to look for the reserved buffer, and the buffer is not freed but reserved at destruction time. The dma_buf_id must be unique for all systems (in the same DMA buffer type) e.g. using snd_dma_pci_buf_id. Returns zero if successful, or a negative error code on failure. snd_pcm_lib_preallocate_pages_for_all snd_pcm_lib_preallocate_pages_for_all pre-allocation for continous memory type (all substreams) int snd_pcm_lib_preallocate_pages_for_all struct snd_pcm * pcm int type void * data size_t size size_t max pcm the pcm instance type DMA type (SNDRV_DMA_TYPE_*) data DMA type dependant data size the requested pre-allocation size in bytes max the max. allowed pre-allocation size Do pre-allocation to all substreams of the given pcm for the specified DMA type. Returns zero if successful, or a negative error code on failure. snd_pcm_sgbuf_ops_page snd_pcm_sgbuf_ops_page get the page struct at the given offset struct page * snd_pcm_sgbuf_ops_page struct snd_pcm_substream * substream unsigned long offset substream the pcm substream instance offset the buffer offset Returns the page struct at the given buffer offset. Used as the page callback of PCM ops. snd_pcm_lib_malloc_pages snd_pcm_lib_malloc_pages allocate the DMA buffer int snd_pcm_lib_malloc_pages struct snd_pcm_substream * substream size_t size substream the substream to allocate the DMA buffer to size the requested buffer size in bytes Allocates the DMA buffer on the BUS type given earlier to snd_pcm_lib_preallocate_xxx_pages. Returns 1 if the buffer is changed, 0 if not changed, or a negative code on failure. snd_pcm_lib_free_pages snd_pcm_lib_free_pages release the allocated DMA buffer. int snd_pcm_lib_free_pages struct snd_pcm_substream * substream substream the substream to release the DMA buffer Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages. Returns zero if successful, or a negative error code on failure. snd_ctl_new1 snd_ctl_new1 create a control instance from the template struct snd_kcontrol * snd_ctl_new1 const struct snd_kcontrol_new * ncontrol void * private_data ncontrol the initialization record private_data the private data to set 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. When the count field is 0, it's assumes as one. Returns the pointer of the newly generated instance, or NULL on failure. snd_ctl_free_one snd_ctl_free_one release the control instance void snd_ctl_free_one struct snd_kcontrol * kcontrol kcontrol the control instance 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. snd_ctl_add snd_ctl_add add the control instance to the card int snd_ctl_add struct snd_card * card struct snd_kcontrol * kcontrol card the card instance kcontrol the control instance to add 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. Returns zero if successful, or a negative error code on failure. It frees automatically the control which cannot be added. snd_ctl_remove snd_ctl_remove remove the control from the card and release it int snd_ctl_remove struct snd_card * card struct snd_kcontrol * kcontrol card the card instance kcontrol the control instance to remove 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 - down_write(&card->controls_rwsem). Returns 0 if successful, or a negative error code on failure. snd_ctl_remove_id snd_ctl_remove_id remove the control of the given id and release it int snd_ctl_remove_id struct snd_card * card struct snd_ctl_elem_id * id card the card instance id the control id to remove Finds the control instance with the given id, removes it from the card list and releases it. Returns 0 if successful, or a negative error code on failure. snd_ctl_rename_id snd_ctl_rename_id replace the id of a control on the card int snd_ctl_rename_id struct snd_card * card struct snd_ctl_elem_id * src_id struct snd_ctl_elem_id * dst_id card the card instance src_id the old id dst_id the new id Finds the control with the old id from the card, and replaces the id with the new one. Returns zero if successful, or a negative error code on failure. snd_ctl_find_numid snd_ctl_find_numid find the control instance with the given number-id struct snd_kcontrol * snd_ctl_find_numid struct snd_card * card unsigned int numid card the card instance numid the number-id to search Finds the control instance with the given number-id from the card. Returns the pointer of the instance if found, or NULL if not. The caller must down card->controls_rwsem before calling this function (if the race condition can happen). snd_ctl_find_id snd_ctl_find_id find the control instance with the given id struct snd_kcontrol * snd_ctl_find_id struct snd_card * card struct snd_ctl_elem_id * id card the card instance id the id to search Finds the control instance with the given id from the card. Returns the pointer of the instance if found, or NULL if not. The caller must down card->controls_rwsem before calling this function (if the race condition can happen). snd_ac97_write snd_ac97_write write a value on the given register void snd_ac97_write struct snd_ac97 * ac97 unsigned short reg unsigned short value ac97 the ac97 instance reg the register to change value the value to set Writes a value on the given register. This will invoke the write callback directly after the register check. This function doesn't change the register cache unlike #snd_ca97_write_cache, so use this only when you don't want to reflect the change to the suspend/resume state. snd_ac97_read snd_ac97_read read a value from the given register unsigned short snd_ac97_read struct snd_ac97 * ac97 unsigned short reg ac97 the ac97 instance reg the register to read Reads a value from the given register. This will invoke the read callback directly after the register check. Returns the read value. Reads a value from the given register. This will invoke the read callback directly after the register check. Returns the read value. snd_ac97_write_cache snd_ac97_write_cache write a value on the given register and update the cache void snd_ac97_write_cache struct snd_ac97 * ac97 unsigned short reg unsigned short value ac97 the ac97 instance reg the register to change value the value to set Writes a value on the given register and updates the register cache. The cached values are used for the cached-read and the suspend/resume. snd_ac97_update snd_ac97_update update the value on the given register int snd_ac97_update struct snd_ac97 * ac97 unsigned short reg unsigned short value ac97 the ac97 instance reg the register to change value the value to set Compares the value with the register cache and updates the value only when the value is changed. Returns 1 if the value is changed, 0 if no change, or a negative code on failure. snd_ac97_update_bits snd_ac97_update_bits update the bits on the given register int snd_ac97_update_bits struct snd_ac97 * ac97 unsigned short reg unsigned short mask unsigned short value ac97 the ac97 instance reg the register to change mask the bit-mask to change value the value to set Updates the masked-bits on the given register only when the value is changed. Returns 1 if the bits are changed, 0 if no change, or a negative code on failure. snd_ac97_get_short_name snd_ac97_get_short_name retrieve codec name const char * snd_ac97_get_short_name struct snd_ac97 * ac97 ac97 the codec instance Returns the short identifying name of the codec. snd_ac97_bus snd_ac97_bus create an AC97 bus component int snd_ac97_bus struct snd_card * card int num struct snd_ac97_bus_ops * ops void * private_data struct snd_ac97_bus ** rbus card the card instance num the bus number ops the bus callbacks table private_data private data pointer for the new instance rbus the pointer to store the new AC97 bus instance. Creates an AC97 bus component. An struct snd_ac97_bus instance is newly allocated and initialized. The ops table must include valid callbacks (at least read and write). The other callbacks, wait and reset, are not mandatory. The clock is set to 48000. If another clock is needed, set (*rbus)->clock manually. The AC97 bus instance is registered as a low-level device, so you don't have to release it manually. Returns zero if successful, or a negative error code on failure. snd_ac97_mixer snd_ac97_mixer create an Codec97 component int snd_ac97_mixer struct snd_ac97_bus * bus struct snd_ac97_template * template struct snd_ac97 ** rac97 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. Creates an Codec97 component. An struct snd_ac97 instance is newly allocated and initialized from the template. The codec is then initialized by the standard procedure. The template must include the codec number (num) and address (addr), and the private data (private_data). The ac97 instance is registered as a low-level device, so you don't have to release it manually. Returns zero if successful, or a negative error code on failure. snd_ac97_update_power snd_ac97_update_power update the powerdown register int snd_ac97_update_power struct snd_ac97 * ac97 int reg int powerup ac97 the codec instance reg the rate register, e.g. AC97_PCM_FRONT_DAC_RATE powerup non-zero when power up the part Update the AC97 powerdown register bits of the given part. snd_ac97_suspend snd_ac97_suspend General suspend function for AC97 codec void snd_ac97_suspend struct snd_ac97 * ac97 ac97 the ac97 instance Suspends the codec, power down the chip. snd_ac97_resume snd_ac97_resume General resume function for AC97 codec void snd_ac97_resume struct snd_ac97 * ac97 ac97 the ac97 instance Do the standard resume procedure, power up and restoring the old register values. snd_ac97_tune_hardware snd_ac97_tune_hardware tune up the hardware int snd_ac97_tune_hardware struct snd_ac97 * ac97 struct ac97_quirk * quirk const char * override ac97 the ac97 instance quirk quirk list override explicit quirk value (overrides the list if non-NULL) Do some workaround for each pci device, such as renaming of the headphone (true line-out) control as Master. The quirk-list must be terminated with a zero-filled entry. Returns zero if successful, or a negative error code on failure. snd_ac97_set_rate snd_ac97_set_rate change the rate of the given input/output. int snd_ac97_set_rate struct snd_ac97 * ac97 int reg unsigned int rate ac97 the ac97 instance reg the register to change rate the sample rate to set Changes the rate of the given input/output on the codec. If the codec doesn't support VAR, the rate must be 48000 (except for SPDIF). The valid registers are AC97_PMC_MIC_ADC_RATE, AC97_PCM_FRONT_DAC_RATE, AC97_PCM_LR_ADC_RATE. AC97_PCM_SURR_DAC_RATE and AC97_PCM_LFE_DAC_RATE are accepted if the codec supports them. AC97_SPDIF is accepted as a pseudo register to modify the SPDIF status bits. Returns zero if successful, or a negative error code on failure. snd_ac97_pcm_assign snd_ac97_pcm_assign assign AC97 slots to given PCM streams int snd_ac97_pcm_assign struct snd_ac97_bus * bus unsigned short pcms_count const struct ac97_pcm * pcms bus the ac97 bus instance pcms_count count of PCMs to be assigned pcms PCMs to be assigned It assigns available AC97 slots for given PCMs. If none or only some slots are available, pcm->xxx.slots and pcm->xxx.rslots[] members are reduced and might be zero. snd_ac97_pcm_open snd_ac97_pcm_open opens the given AC97 pcm int snd_ac97_pcm_open struct ac97_pcm * pcm unsigned int rate enum ac97_pcm_cfg cfg unsigned short slots 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 pcm It locks the specified slots and sets the given rate to AC97 registers. snd_ac97_pcm_close snd_ac97_pcm_close closes the given AC97 pcm int snd_ac97_pcm_close struct ac97_pcm * pcm pcm the ac97 pcm instance It frees the locked AC97 slots. snd_ac97_pcm_double_rate_rules snd_ac97_pcm_double_rate_rules set double rate constraints int snd_ac97_pcm_double_rate_rules struct snd_pcm_runtime * runtime runtime the runtime of the ac97 front playback pcm Installs the hardware constraint rules to prevent using double rates and more than two channels at the same time. snd_rawmidi_receive snd_rawmidi_receive receive the input data from the device int snd_rawmidi_receive struct snd_rawmidi_substream * substream const unsigned char * buffer int count substream the rawmidi substream buffer the buffer pointer count the data size to read Reads the data from the internal buffer. Returns the size of read data, or a negative error code on failure. snd_rawmidi_transmit_empty snd_rawmidi_transmit_empty check whether the output buffer is empty int snd_rawmidi_transmit_empty struct snd_rawmidi_substream * substream substream the rawmidi substream Returns 1 if the internal output buffer is empty, 0 if not. snd_rawmidi_transmit_peek snd_rawmidi_transmit_peek copy data from the internal buffer int snd_rawmidi_transmit_peek