fix espressif serial over uart

Author: microdev1

ports/espressif/common-hal/busio/UART.c

@@ -38,6 +38,8 @@
 #include "supervisor/shared/translate.h"
 #include "supervisor/shared/tick.h"
 
+uint8_t never_reset_uart_mask = 0;
+
 void uart_reset(void) {
     for (uart_port_t num = 0; num < UART_NUM_MAX; num++) {
         // Ignore the UART used by the IDF.
@@ -46,12 +48,20 @@ void uart_reset(void) {
             continue;
         }
         #endif
-        if (uart_is_driver_installed(num)) {
+        if (uart_is_driver_installed(num) && !(never_reset_uart_mask & 1 << num)) {
             uart_driver_delete(num);
         }
     }
 }
 
+void common_hal_busio_uart_never_reset(busio_uart_obj_t *self) {
+    common_hal_never_reset_pin(self->rx_pin);
+    common_hal_never_reset_pin(self->tx_pin);
+    common_hal_never_reset_pin(self->rts_pin);
+    common_hal_never_reset_pin(self->cts_pin);
+    never_reset_uart_mask |= 1 << self->uart_num;
+}
+
 void common_hal_busio_uart_construct(busio_uart_obj_t *self,
     const mcu_pin_obj_t *tx, const mcu_pin_obj_t *rx,
     const mcu_pin_obj_t *rts, const mcu_pin_obj_t *cts,

ports/espressif/common-hal/microcontroller/Pin.c

@@ -58,6 +58,9 @@ void never_reset_pin_number(gpio_num_t pin_number) {
 }
 
 void common_hal_never_reset_pin(const mcu_pin_obj_t *pin) {
+    if (pin == NULL) {
+        return;
+    }
     never_reset_pin_number(pin->number);
 }
 

ports/espressif/common-hal/microcontroller/Pin.h

@@ -36,6 +36,7 @@ void reset_all_pins(void);
 // need to store a full pointer.
 void reset_pin_number(gpio_num_t pin_number);
 void common_hal_reset_pin(const mcu_pin_obj_t *pin);
+void common_hal_never_reset_pin(const mcu_pin_obj_t *pin);
 void claim_pin(const mcu_pin_obj_t *pin);
 void claim_pin_number(gpio_num_t pin_number);
 bool pin_number_is_free(gpio_num_t pin_number);