stmhal: Use MP_OBJ_NEW_SMALL_INT directly in pyb.micros/millis.

Also some whitespace cleanup.

stmhal/modpyb.c

@@ -198,11 +198,10 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_sync_obj, pyb_sync);
 /// always get the right answer and not have to worry about whether pyb.millis()
 /// wraps around.
 STATIC mp_obj_t pyb_millis(void) {
-    // We want to "cast" the 32 bit unsigned into a small-int. So we shift it
-    // left by 1 to throw away the top bit, and then shift it right by one
-    // to sign extend.
-    mp_int_t val = HAL_GetTick() << 1;
-    return mp_obj_new_int(val >> 1);
+    // We want to "cast" the 32 bit unsigned into a small-int.  This means
+    // copying the MSB down 1 bit (extending the sign down), which is
+    // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro.
+    return MP_OBJ_NEW_SMALL_INT(HAL_GetTick());
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_millis_obj, pyb_millis);
 
@@ -219,11 +218,10 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_millis_obj, pyb_millis);
 /// always get the right answer and not have to worry about whether pyb.micros()
 /// wraps around.
 STATIC mp_obj_t pyb_micros(void) {
-    // We want to "cast" the 32 bit unsigned into a small-int. So we shift it
-    // left by 1 to throw away the top bit, and then shift it right by one
-    // to sign extend.
-    mp_int_t val = sys_tick_get_microseconds() << 1;
-    return mp_obj_new_int(val >> 1);
+    // We want to "cast" the 32 bit unsigned into a small-int.  This means
+    // copying the MSB down 1 bit (extending the sign down), which is
+    // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro.
+    return MP_OBJ_NEW_SMALL_INT(sys_tick_get_microseconds());
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_micros_obj, pyb_micros);
 

stmhal/systick.c

@@ -51,11 +51,11 @@ void sys_tick_wait_at_least(uint32_t start_tick, uint32_t delay_ms) {
 //
 // We assume that HAL_GetTickis returns milliseconds.
 uint32_t sys_tick_get_microseconds(void) {
-    mp_int_t enabled = disable_irq();
+    mp_uint_t irq_state = disable_irq();
     uint32_t counter = SysTick->VAL;
     uint32_t milliseconds = HAL_GetTick();
     uint32_t status  = SysTick->CTRL;
-    enable_irq(enabled);
+    enable_irq(irq_state);
 
     // It's still possible for the countflag bit to get set if the counter was
     // reloaded between reading VAL and reading CTRL. With interrupts  disabled

teensy/teensy_hal.h

@@ -113,25 +113,20 @@ typedef struct {
 #define GPIO_AF6_I2C1   6
 #define GPIO_AF7_FTM1   7
 
-
-__attribute__(( always_inline )) static inline void __WFI(void)
-{
+__attribute__(( always_inline )) static inline void __WFI(void) {
   __asm volatile ("wfi");
 }
 
-__attribute__(( always_inline )) static inline uint32_t __get_PRIMASK(void)
-{
+__attribute__(( always_inline )) static inline uint32_t __get_PRIMASK(void) {
     uint32_t result;
     __asm volatile ("MRS %0, primask" : "=r" (result));
     return(result);
 }
 
-__attribute__(( always_inline )) static inline void __set_PRIMASK(uint32_t priMask)
-{
+__attribute__(( always_inline )) static inline void __set_PRIMASK(uint32_t priMask) {
     __asm volatile ("MSR primask, %0" : : "r" (priMask) : "memory");
 }
 
-
 uint32_t HAL_GetTick(void);
 void     HAL_Delay(uint32_t Delay);