for (int i = 0; i < 4; ++i)
{
    dataFilterADC[i] = func(buffVal[i]);
}

uint16_t func(uint16_t buff[32])

uint16_t func(uint16_t len, uint16_t buff[len])

dataFilterADC[i] = func(32, buffVal[i]);

uint16_t func(uint16_t* buff[chanel])

dataFilterADC[i] = func(buffVal[i]);

#include <stdint.h>

uint16_t dataFilterADC[4];
uint16_t buffVal[4][32];

uint16_t func(uint16_t *buff)  // (1)
//uint16_t func(uint16_t buff[32]) // (2)
//uint16_t func(uint16_t *buff[32]) // (3)
{
    uint32_t tmp = 0;
                            
    for (int i = 0; i < 32; ++i) {
        tmp += buff[i];
    }
    return (uint16_t) tmp / 32;
}

void moo()
{
    for (int i = 0; i < 4; ++i) 
        dataFilterADC[i] = func(buffVal[i]);
}

arr.c: In function ‘func’:
arr.c:13:7: warning: assignment makes integer from pointer without a cast [-Wint-conversion]
   tmp += buff[i];
       ^~
arr.c: In function ‘moo’:
arr.c:21:27: warning: passing argument 1 of ‘func’ from incompatible pointer type [-Wincompatible-pointer-types]
   dataFilterADC[i] = func(buffVal[i]);
                           ^~~~~~~
arr.c:8:10: note: expected ‘uint16_t ** {aka short unsigned int **}’ but argument is of type ‘uint16_t * {aka short unsigned int *}’
 uint16_t func(uint16_t *buff[32]) // (3)
          ^~~~

#define ROW_LENGTH 32
#define ROW_COUNT 4

typedef uint16_t Row[ROW_LENGTH]; //рядок

Row buffVal[ROW_COUNT];

uint16_t func(Row *buff) //те саме, що й uint16_t func(uint16_t buff[ROW_LENGTH]) або uint16_t func(uint16_t *buff[ROW_LENGTH]), але наочніше
{
    uint16_t tmp;
        
    for (int i = 0; i < ROW_LENGTH; ++i)
    {
        tmp += buff[i];
    }
 
    return tmp / ROW_LENGTH; // для цілих / дає цілий результат
}

...
uint16_t dataFilterADC[ROW_COUNT];
for (int i = 0; i < ROW_COUNT; ++i)
{
    dataFilterADC[i] = func(buffVal[i]);
}