Using DAQmx driver in a kernel space application

[victorCosta]

Hello, 
I don't know if this is the proper Forum, but I'm trying to build a kernel module which uses DAQmx in a CentOs7.5. So far I've installed DAQmx for linux and successfully built an user space application given as an example by NI and I've tried to build a similar application in kernel space. When I tried to compile that I got this message :
"WARNING: "DAQmxStopTask" [...] undefined!" 
I know that this message normally happens if a dependence is not properly set or loaded, but I know, through lsmod, that ni's modules are loaded in my machine, so I'd like to know how to proper  interface DAQmx to a kernel module.
For reference, here is my code

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/stringify.h>
#include <linux/cdev.h>
#include <asm/io.h>

#include <NIDAQmx.h>

MODULE_LICENSE("GPL");              
MODULE_AUTHOR("Victor Costa");      
MODULE_DESCRIPTION("DAQMX_LOADER using drivers");
MODULE_VERSION("0.1");

static int error=0;
static char errBuff[2048]={'\0'};
static TaskHandle  taskHandle=0;
static double data[1000];

static void error_handler(void);
static int CVICALLBACK DoneCallback(TaskHandle taskHandle, int status, void *callbackData);
#define DAQmxErrChk(functionCall) if( DAQmxFailed(error=(functionCall)) ) goto Error; else



static int __module_init (void)
{
	printk(KERN_DEBUG "DAQMX<1>: Loading Module\n");
	for(int i=0;i<1000;i++)
		data[i] = 9.95;

	DAQmxErrChk (DAQmxCreateTask("",&taskHandle));
	DAQmxErrChk (DAQmxCreateAOVoltageChan(taskHandle,"Dev1/ao0","",-10.0,10.0,DAQmx_Val_Volts,NULL));
	DAQmxErrChk (DAQmxCfgSampClkTiming(taskHandle,"",1000.0,DAQmx_Val_Rising,DAQmx_Val_ContSamps,1000));

	DAQmxErrChk (DAQmxRegisterDoneEvent(taskHandle,0,DoneCallback,NULL));

	/*********************************************/
	// DAQmx Write Code
	/*********************************************/
	DAQmxErrChk (DAQmxWriteAnalogF64(taskHandle,1000,0,10.0,DAQmx_Val_GroupByChannel,data,NULL,NULL));

	/*********************************************/
	// DAQmx Start Code
	/*********************************************/
	DAQmxErrChk (DAQmxStartTask(taskHandle));
	Error: error_handler();
	return 0;
}

static void __module_exit (void)
{

	printk(KERN_DEBUG "DAQMX<1>: Unloading Module\n");
}

module_init(__module_init);
module_exit(__module_exit);    

static void error_handler(void)
{
	if( DAQmxFailed(error) )
		DAQmxGetExtendedErrorInfo(errBuff,2048);
	if( taskHandle!=0 ) {
		/*********************************************/
		// DAQmx Stop Code
		/*********************************************/
		DAQmxStopTask(taskHandle);
		DAQmxClearTask(taskHandle);
	}
	if( DAQmxFailed(error) )
		printk(KERN_DEBUG"DAQMX<1> Error: %s\n",errBuff);
}

static int CVICALLBACK DoneCallback(TaskHandle taskHandle, int32 status, void *callbackData)
{
	char    errBuff[2048]={'\0'};

	// Check to see if an error stopped the task.
	DAQmxErrChk (status);

Error:
	if( DAQmxFailed(error) ) {
		DAQmxGetExtendedErrorInfo(errBuff,2048);
		DAQmxClearTask(taskHandle);
		printk(KERN_DEBUG"DAQMX<1> Error: %s\n",errBuff);
	}
	return 0;
}