stm32: timer: Add API to set external clock mode 2

include/libopencm3/stm32/common/timer_common_all.h

@@ -1143,6 +1143,12 @@ enum tim_et_pol {
 	TIM_ET_FALLING,
 };
 
+/** External clock mode 2 */
+enum tim_ecm2_state {
+    TIM_ECM2_DISABLED,
+    TIM_ECM2_ENABLED,
+};
+
 /* --- TIM function prototypes --------------------------------------------- */
 
 BEGIN_DECLS
@@ -1233,6 +1239,8 @@ void timer_slave_set_prescaler(uint32_t timer, enum tim_ic_psc psc);
 void timer_slave_set_polarity(uint32_t timer, enum tim_et_pol pol);
 void timer_slave_set_mode(uint32_t timer, uint8_t mode);
 void timer_slave_set_trigger(uint32_t timer, uint8_t trigger);
+void timer_slave_set_extclockmode2(uint32_t timer_peripheral,
+            enum tim_ecm2_state state);
 
 END_DECLS
 

lib/stm32/common/timer_common_all.c

@@ -1864,6 +1864,23 @@ void timer_slave_set_trigger(uint32_t timer_peripheral, uint8_t trigger)
 	TIM_SMCR(timer_peripheral) |= trigger;
 }
 
+/*---------------------------------------------------------------------------*/
+/** @brief Set External Clock Mode 2
+
+@param[in] timer_peripheral Unsigned int32. Timer register address base
+@param[in] state ::tim_ecm2_state. External Clock Mode 2 state
+*/
+
+void timer_slave_set_extclockmode2(uint32_t timer_peripheral,
+            enum tim_ecm2_state state)
+{
+	if (state) {
+		TIM_SMCR(timer_peripheral) |= TIM_SMCR_ECE;
+	} else {
+		TIM_SMCR(timer_peripheral) &= ~TIM_SMCR_ECE;
+	}
+}
+
 /* TODO Timer DMA burst */
 
 /**@}*/