relay_subbufs_consumed(9) [suse man page]

RELAY_SUBBUFS_CONSUM(9) 				      relay interface support					   RELAY_SUBBUFS_CONSUM(9)

NAME

       relay_subbufs_consumed - update the buffer's sub-buffers-consumed count

SYNOPSIS

       void relay_subbufs_consumed(struct rchan * chan, unsigned int cpu, size_t subbufs_consumed);

ARGUMENTS

       chan
	   the channel

       cpu
	   the cpu associated with the channel buffer to update

       subbufs_consumed
	   number of sub-buffers to add to current buf's count

DESCRIPTION

       Adds to the channel buffer's consumed sub-buffer count. subbufs_consumed should be the number of sub-buffers newly consumed, not the total
       consumed.

       NOTE. Kernel clients don't need to call this function if the channel mode is 'overwrite'.

COPYRIGHT

Kernel Hackers Manual 2.6.					     July 2010						   RELAY_SUBBUFS_CONSUM(9)

EGD_ACQ_SETUP(3)					       EEGDEV library manual						  EGD_ACQ_SETUP(3)

NAME

       egd_acq_setup - specify which and how channel data should be obtained

SYNOPSIS

       #include <eegdev.h>

       int egd_acq_setup(struct eegdev* dev,
			 unsigned int narr, const size_t *strides,
			 unsigned int ngrp, const struct grpconf *grp);

DESCRIPTION

       egd_acq_setup() configures the way data is provided by the device referenced by dev for the next calls to egd_get_data(3).

       The  narr  argument specifies the number of buffers that will be supplied in the argument list of egd_get_data(3). strides should points to
       an array of narr values specifying respectively for each buffers its stride, i.e. the size in bytes between the data of two successive sam-
       ples in this buffer.

       The  channels  data  that  must	be  returns in those buffers are defined by ngrp groups of consecutive channels. The groups definition are
       passed by grp which points to an array of ngrp structures, defined as follows:

	   struct grpconf {
	       unsigned int sensortype;    /* type of channel */
	       unsigned int index;	   /* index of the first channel */
	       unsigned int nch;	   /* number of channels */
	       unsigned int iarray;	   /* index of the array */
	       unsigned int arr_offset;    /* offset in the array */
	       unsigned int datatype;	   /* type in the array */
	   };

       The different fields in the structure defines the properties of the group:

	* sensortype specifies the type of channel. it must one of the following values returned by egd_sensor_type(3).

	* index indicates the index of the first channel in the group. Note that channel index i refers the i-th channel  of  the  type  specified
	  previously, i.e. the channel index i refers to two differents channels if sensortype differs.

	* nch specifies the number of consecutive channels that should be in the group.

	* iarray indicates which buffer the data of the channel group must be written to.

	* arr_offset defines the offset of the memory location of the data in the buffers relatively to the beginning of each sample.

	* datatype  specifies  the type of data that must be written to the buffer. It must be one of the following value: EGD_INT32, EGD_FLOAT or
	  EGD_DOUBLE

RETURN VALUE

       The function returns 0 in case of succes. Otherwise, -1 is returned and errno is set accordingly.

ERRORS

       egd_acq_setup() will fail if:

       EINVAL dev is NULL.

       EPERM  The acquisition is running

THREAD SAFETY

       egd_acq_setup() is thread-safe.

EXAMPLE

       See egd_get_data(3) for a example

SEE ALSO

       egd_get_data(3), egd_start(3), egd_sensor_type(3)

EPFL
								       2010							  EGD_ACQ_SETUP(3)