Merge pull request #13003 from benpicco/lpc2387-timer

cpu/lpc23xx/include/periph_cpu.h

@@ -128,6 +128,11 @@ typedef struct {
  */
 #define TIMER_CHANNEL_NUMOF (4U)
 
+/**
+ * @brief   Prevent shared timer functions from being used
+ */
+#define PERIPH_TIMER_PROVIDES_SET
+
 /**
  * @brief   Declare needed generic SPI functions
  * @{

cpu/lpc23xx/periph/timer.c

@@ -21,6 +21,7 @@
 #include <stdint.h>
 #include <string.h>
 
+#include "irq.h"
 #include "periph_conf.h"
 #include "periph_cpu.h"
 #include "periph/timer.h"
@@ -167,6 +168,37 @@ int timer_set_absolute(tim_t tim, int channel, unsigned int value)
     dev->MR[channel] = value;
     /* Match Interrupt */
     dev->MCR |= (1 << (channel * 3));
+
+    return 0;
+}
+
+int timer_set(tim_t tim, int channel, unsigned int timeout)
+{
+    if (((unsigned) tim >= TIMER_NUMOF) || ((unsigned) channel >= TIMER_CHANNEL_NUMOF)) {
+        return -1;
+    }
+
+    /* Interrupt will only be generated on increment,
+       so a 0 timeout is not possible */
+    if (timeout == 0) {
+        timeout = 1;
+    }
+
+    lpc23xx_timer_t *dev = get_dev(tim);
+
+    unsigned state = irq_disable();
+    dev->TCR = 0;
+
+    unsigned absolute = timeout + dev->TC;
+    unsigned mask = 1 << (channel * 3);
+
+    dev->MR[channel] = absolute;
+    dev->MCR |= mask;
+    set_oneshot(tim, channel);
+
+    dev->TCR = 1;
+    irq_restore(state);
+
     return 0;
 }
 
@@ -226,13 +258,6 @@ void timer_stop(tim_t tim)
 
 static inline void chan_handler(lpc23xx_timer_t *dev, unsigned tim_num, unsigned chan_num)
 {
-    const uint32_t mask = (1 << chan_num);
-
-    if ((dev->IR & mask) == 0) {
-        return;
-    }
-
-    dev->IR |= mask;
     if (is_oneshot(tim_num, chan_num)) {
         dev->MCR &= ~(1 << (chan_num * 3));
     }
@@ -242,8 +267,15 @@ static inline void chan_handler(lpc23xx_timer_t *dev, unsigned tim_num, unsigned
 
 static inline void isr_handler(lpc23xx_timer_t *dev, int tim_num)
 {
-    for (unsigned i = 0; i < TIMER_CHANNEL_NUMOF; ++i) {
+    uint32_t state = dev->IR;
-        chan_handler(dev, tim_num, i);
+    uint8_t chan = 0;
+
+    /* clear interrupt flags */
+    dev->IR = state;
+
+    while (state) {
+        state = bitarithm_test_and_clear(state, &chan);
+        chan_handler(dev, tim_num, chan);
     }
 
     /* we must not forget to acknowledge the handling of the interrupt */