Tidy up atomicity in timer.c and ring_buffer.h

Adopt the macros for saving/restoring the interrupt state
that are provided by the avr gcc environment.

Removing intialization of the timer value; this shaves off
a few bytes because globals are default initialized to zero.
pull/913/head
Wez Furlong 8 years ago
parent 1585fc4b61
commit be4e75423a

@ -17,6 +17,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/atomic.h>
#include <stdint.h>
#include "timer_avr.h"
#include "timer.h"
@ -24,7 +25,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
// counter resolution 1ms
// NOTE: union { uint32_t timer32; struct { uint16_t dummy; uint16_t timer16; }}
volatile uint32_t timer_count = 0;
volatile uint32_t timer_count;
void timer_init(void)
{
@ -52,10 +53,9 @@ void timer_init(void)
inline
void timer_clear(void)
{
uint8_t sreg = SREG;
cli();
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
timer_count = 0;
SREG = sreg;
}
}
inline
@ -63,10 +63,9 @@ uint16_t timer_read(void)
{
uint32_t t;
uint8_t sreg = SREG;
cli();
t = timer_count;
SREG = sreg;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
t = timer_count;
}
return (t & 0xFFFF);
}
@ -76,10 +75,9 @@ uint32_t timer_read32(void)
{
uint32_t t;
uint8_t sreg = SREG;
cli();
t = timer_count;
SREG = sreg;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
t = timer_count;
}
return t;
}
@ -89,10 +87,9 @@ uint16_t timer_elapsed(uint16_t last)
{
uint32_t t;
uint8_t sreg = SREG;
cli();
t = timer_count;
SREG = sreg;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
t = timer_count;
}
return TIMER_DIFF_16((t & 0xFFFF), last);
}
@ -102,10 +99,9 @@ uint32_t timer_elapsed32(uint32_t last)
{
uint32_t t;
uint8_t sreg = SREG;
cli();
t = timer_count;
SREG = sreg;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
t = timer_count;
}
return TIMER_DIFF_32(t, last);
}

@ -4,13 +4,13 @@
* Ring buffer to store scan codes from keyboard
*------------------------------------------------------------------*/
#define RBUF_SIZE 32
#include <util/atomic.h>
static uint8_t rbuf[RBUF_SIZE];
static uint8_t rbuf_head = 0;
static uint8_t rbuf_tail = 0;
static inline void rbuf_enqueue(uint8_t data)
{
uint8_t sreg = SREG;
cli();
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
uint8_t next = (rbuf_head + 1) % RBUF_SIZE;
if (next != rbuf_tail) {
rbuf[rbuf_head] = data;
@ -18,36 +18,34 @@ static inline void rbuf_enqueue(uint8_t data)
} else {
print("rbuf: full\n");
}
SREG = sreg;
}
}
static inline uint8_t rbuf_dequeue(void)
{
uint8_t val = 0;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
uint8_t sreg = SREG;
cli();
if (rbuf_head != rbuf_tail) {
val = rbuf[rbuf_tail];
rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
}
SREG = sreg;
}
return val;
}
static inline bool rbuf_has_data(void)
{
uint8_t sreg = SREG;
cli();
bool has_data = (rbuf_head != rbuf_tail);
SREG = sreg;
return has_data;
bool has_data;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
has_data = (rbuf_head != rbuf_tail);
}
return has_data;
}
static inline void rbuf_clear(void)
{
uint8_t sreg = SREG;
cli();
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
rbuf_head = rbuf_tail = 0;
SREG = sreg;
}
}
#endif /* RING_BUFFER_H */

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