tmk_core/protocol/pbuff.h

   1 /*--------------------------------------------------------------------
   2  * Ring buffer to store scan codes from keyboard
   3  *------------------------------------------------------------------*/
   4
   5 #ifndef PBUFF_H
   6 #define PBUFF_H
   7
   8 #include "print.h"
   9
  10 #define PBUF_SIZE 32
  11 static uint16_t pbuf[PBUF_SIZE];
  12 static uint16_t pbuf_head = 0;
  13 static uint16_t pbuf_tail = 0;
  14 static inline void pbuf_enqueue(uint16_t data)
  15 {
  16     uint8_t sreg = SREG;
  17     cli();
  18     uint16_t next = (pbuf_head + 1) % PBUF_SIZE;
  19     if (next != pbuf_tail) {
  20         pbuf[pbuf_head] = data;
  21         pbuf_head = next;
  22     } else {
  23         print("pbuf: full\n");
  24     }
  25     SREG = sreg;
  26 }
  27 static inline uint16_t pbuf_dequeue(void)
  28 {
  29     uint16_t val = 0;
  30
  31     uint8_t sreg = SREG;
  32     cli();
  33     if (pbuf_head != pbuf_tail) {
  34         val = pbuf[pbuf_tail];
  35         pbuf_tail = (pbuf_tail + 1) % PBUF_SIZE;
  36     }
  37     SREG = sreg;
  38
  39     return val;
  40 }
  41 static inline bool pbuf_has_data(void)
  42 {
  43     uint8_t sreg = SREG;
  44     cli();
  45     bool has_data = (pbuf_head != pbuf_tail);
  46     SREG = sreg;
  47     return has_data;
  48 }
  49 static inline void pbuf_clear(void)
  50 {
  51     uint8_t sreg = SREG;
  52     cli();
  53     pbuf_head = pbuf_tail = 0;
  54     SREG = sreg;
  55 }
  56
  57 #endif