Fix GPIO AF settings being overridden by timerInit(). (#12886)

src/main/drivers/at32/timer_at32bsp.c

@@ -671,6 +671,10 @@ _TIM_IRQ_HANDLER(TMR20_CH_IRQnHandler, 20);
 #endif
 
 
+void timerIOInit(void)
+{
+}
+
 void timerInit(void)
 {
     memset(timerConfig, 0, sizeof(timerConfig));

src/main/drivers/stm32/timer_hal.c

@@ -1028,14 +1028,6 @@ void timerInit(void)
         RCC_ClockCmd(timerRCC(TIMER_HARDWARE[i].tim), ENABLE);
     }
 
-#if defined(STM32F4) || defined(STM32F7) || defined(STM32H7)
-    for (unsigned timerIndex = 0; timerIndex < TIMER_CHANNEL_COUNT; timerIndex++) {
-        const timerHardware_t *timerHardwarePtr = &TIMER_HARDWARE[timerIndex];
-        // XXX IOConfigGPIOAF in timerInit should eventually go away.
-        IOConfigGPIOAF(IOGetByTag(timerHardwarePtr->tag), IOCFG_AF_PP, timerHardwarePtr->alternateFunction);
-    }
-#endif
-
     /* enable the timer peripherals */
     for (unsigned i = 0; i < TIMER_CHANNEL_COUNT; i++) {
         RCC_ClockCmd(timerRCC(TIMER_HARDWARE[i].tim), ENABLE);
@@ -1051,6 +1043,17 @@ void timerInit(void)
     }
 }
 
+void timerIOInit(void)
+{
+#if defined(STM32F4) || defined(STM32F7) || defined(STM32H7)
+    for (unsigned timerIndex = 0; timerIndex < TIMER_CHANNEL_COUNT; timerIndex++) {
+        const timerHardware_t *timerHardwarePtr = &TIMER_HARDWARE[timerIndex];
+        // XXX IOConfigGPIOAF in timerInit should eventually go away.
+        IOConfigGPIOAF(IOGetByTag(timerHardwarePtr->tag), IOCFG_AF_PP, timerHardwarePtr->alternateFunction);
+    }
+#endif
+}
+
 // finish configuring timers after allocation phase
 // start timers
 // TODO - Work in progress - initialization routine must be modified/verified to start correctly without timers

src/main/drivers/stm32/timer_stdperiph.c

@@ -851,6 +851,10 @@ void timerInit(void)
     }
 }
 
+void timerIOInit(void)
+{
+    // No-op
+}
 // finish configuring timers after allocation phase
 // start timers
 // TODO - Work in progress - initialization routine must be modified/verified to start correctly without timers

src/main/drivers/timer.h

@@ -127,6 +127,7 @@ void timerConfigure(const timerHardware_t *timHw, uint16_t period, uint32_t hz);
 // Initialisation
 //
 void timerInit(void);
+void timerIOInit(void);
 void timerStart(void);
 
 //

src/main/fc/init.c

@@ -271,6 +271,15 @@ void init(void)
     // initialize IO (needed for all IO operations)
     IOInitGlobal();
 
+#ifdef USE_TIMER
+    // timerIOInit blindly reconfigures GPIO AF for all pins in the fullTimerHardware array regardless
+    // of if the timer pin is used already by something else.
+    // If it is called AFTER the SPI initilisation, any AF settings for the SPI are overridden by timer
+    // AF, making the SPI hang when it's used.
+    // To work-around this issue init timer AF before other AF, such as SPI/QSPI/OSPI/etc.
+    timerIOInit();
+#endif
+
 #ifdef USE_HARDWARE_REVISION_DETECTION
     detectHardwareRevision();
 #endif

src/main/target/SITL/sitl.c

@@ -358,6 +358,10 @@ void timerInit(void)
     printf("[timer]Init...\n");
 }
 
+void timerIOInit(void)
+{
+}
+
 void timerStart(void)
 {
 }