[STM32] Fix pull over write to all families

This applies the same fix as was done for F4 to solve issue #2638.
The fix applies ell to all other families excpet STM32F1.

Basically, to avoid over-writing the pull-up/-down settings, we read the
current state from HW.

targets/TARGET_STM/TARGET_STM32F0/gpio_irq_api.c

@@ -127,6 +127,7 @@ static void gpio_irq2(void) {
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id) {
     IRQn_Type irq_n = (IRQn_Type)0;
@@ -196,8 +197,8 @@ void gpio_irq_free(gpio_irq_t *obj) {
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
@@ -245,7 +246,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable) {
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj) {

targets/TARGET_STM/TARGET_STM32F0/pinmap.c

@@ -138,5 +138,20 @@ void pin_mode(PinName pin, PinMode mode) {
     if (pupd > 2) pupd = 0; // Open-drain = No pull-up/No pull-down
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPDR0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
-
+}
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPDR0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
 }

targets/TARGET_STM/TARGET_STM32F2/gpio_irq_api.c

@@ -163,6 +163,7 @@ static void gpio_irq6(void)
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
 {
@@ -267,15 +268,14 @@ void gpio_irq_free(gpio_irq_t *obj)
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
 void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
 {
     uint32_t mode = STM_MODE_IT_EVT_RESET;
-    uint32_t pull = GPIO_NOPULL;
 
     if (enable) {
         if (event == IRQ_RISE) {
@@ -317,7 +317,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj)

targets/TARGET_STM/TARGET_STM32F2/pinmap.c

@@ -178,5 +178,20 @@ void pin_mode(PinName pin, PinMode mode)
     }
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPDR0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
-
+}
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPDR0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
 }

targets/TARGET_STM/TARGET_STM32F3/gpio_irq_api.c

@@ -163,6 +163,7 @@ static void gpio_irq6(void)
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
 {
@@ -267,15 +268,14 @@ void gpio_irq_free(gpio_irq_t *obj)
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
 void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
 {
     uint32_t mode = STM_MODE_IT_EVT_RESET;
-    uint32_t pull = GPIO_NOPULL;
 
     if (enable) {
         if (event == IRQ_RISE) {
@@ -317,7 +317,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj)

targets/TARGET_STM/TARGET_STM32F3/pinmap.c

@@ -177,3 +177,19 @@ void pin_mode(PinName pin, PinMode mode)
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPDR0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
 }
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPDR0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
+}

targets/TARGET_STM/TARGET_STM32F7/gpio_irq_api.c

@@ -163,6 +163,7 @@ static void gpio_irq6(void)
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
 {
@@ -267,15 +268,14 @@ void gpio_irq_free(gpio_irq_t *obj)
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
 void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
 {
     uint32_t mode = STM_MODE_IT_EVT_RESET;
-    uint32_t pull = GPIO_NOPULL;
 
     if (enable) {
         if (event == IRQ_RISE) {
@@ -317,7 +317,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj)

targets/TARGET_STM/TARGET_STM32F7/pinmap.c

@@ -177,5 +177,20 @@ void pin_mode(PinName pin, PinMode mode)
         pupd = 0; // Open-drain = No pull-up/No pull-down
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPDR0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
-
+}
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPDR0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
 }

targets/TARGET_STM/TARGET_STM32L0/gpio_irq_api.c

@@ -131,6 +131,7 @@ static void gpio_irq2(void)
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
 {
@@ -202,15 +203,14 @@ void gpio_irq_free(gpio_irq_t *obj)
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
 void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
 {
     uint32_t mode = STM_MODE_IT_EVT_RESET;
-    uint32_t pull = GPIO_NOPULL;
 
     if (enable) {
         if (event == IRQ_RISE) {
@@ -252,7 +252,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj)

targets/TARGET_STM/TARGET_STM32L0/pinmap.c

@@ -146,5 +146,20 @@ void pin_mode(PinName pin, PinMode mode)
     }
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPD0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
-
+}
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPD0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
 }

targets/TARGET_STM/TARGET_STM32L1/gpio_irq_api.c

@@ -163,6 +163,7 @@ static void gpio_irq6(void)
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
 {
@@ -267,15 +268,14 @@ void gpio_irq_free(gpio_irq_t *obj)
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
 void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
 {
     uint32_t mode = STM_MODE_IT_EVT_RESET;
-    uint32_t pull = GPIO_NOPULL;
 
     if (enable) {
         if (event == IRQ_RISE) {
@@ -317,7 +317,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj)

targets/TARGET_STM/TARGET_STM32L1/pinmap.c

@@ -139,5 +139,20 @@ void pin_mode(PinName pin, PinMode mode)
     }
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPDR0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
-
+}
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPDR0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
 }

targets/TARGET_STM/TARGET_STM32L4/gpio_irq_api.c

@@ -163,6 +163,7 @@ static void gpio_irq6(void)
 }
 
 extern uint32_t Set_GPIO_Clock(uint32_t port_idx);
+extern void pin_function_gpiomode(PinName pin, uint32_t gpiomode);
 
 int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
 {
@@ -267,15 +268,14 @@ void gpio_irq_free(gpio_irq_t *obj)
     gpio_channel->channel_gpio[gpio_idx] = 0;
     gpio_channel->channel_pin[gpio_idx] = 0;
 
-    // Disable EXTI line
-    pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
+    // Disable EXTI line, but don't change pull-up config
+    pin_function_gpiomode(obj->pin, STM_MODE_INPUT);
     obj->event = EDGE_NONE;
 }
 
 void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
 {
     uint32_t mode = STM_MODE_IT_EVT_RESET;
-    uint32_t pull = GPIO_NOPULL;
 
     if (enable) {
         if (event == IRQ_RISE) {
@@ -317,7 +317,7 @@ void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
         }
     }
 
-    pin_function(obj->pin, STM_PIN_DATA(mode, pull, 0));
+    pin_function_gpiomode(obj->pin, mode);
 }
 
 void gpio_irq_enable(gpio_irq_t *obj)

targets/TARGET_STM/TARGET_STM32L4/pinmap.c

@@ -149,3 +149,19 @@ void pin_mode(PinName pin, PinMode mode)
     gpio->PUPDR &= (uint32_t)(~(GPIO_PUPDR_PUPDR0 << (pin_index * 2)));
     gpio->PUPDR |= (uint32_t)(pupd << (pin_index * 2));
 }
+
+/*  Internal function for setting the gpiomode/function
+ *  without changing Pull mode
+ */
+void pin_function_gpiomode(PinName pin, uint32_t gpiomode) {
+
+    /* Read current pull state from HW to avoid over-write*/
+    uint32_t port_index = STM_PORT(pin);
+    uint32_t pin_index  = STM_PIN(pin);
+    GPIO_TypeDef *gpio = (GPIO_TypeDef *) Set_GPIO_Clock(port_index);
+    uint32_t temp = gpio->PUPDR;
+    uint32_t pull = (temp  >> (pin_index * 2U)) & GPIO_PUPDR_PUPDR0;
+
+    /* Then re-use global function for updating the mode part*/
+    pin_function(pin, STM_PIN_DATA(gpiomode, pull, 0));
+}