Fully implement digitalio and pin-in-use tracking.

Fixes #2901

2 files changed, 12 insertions, 5 deletions

diff --git a/shared-bindings/digitalio/DigitalInOut.c b/shared-bindings/digitalio/DigitalInOut.c
index 0cea74da0..eaf2c1810 100644
--- a/shared-bindings/digitalio/DigitalInOut.c
+++ b/shared-bindings/digitalio/DigitalInOut.c
@@ -131,7 +131,10 @@ STATIC mp_obj_t digitalio_digitalinout_switch_to_output(size_t n_args, const mp_
         drive_mode = DRIVE_MODE_OPEN_DRAIN;
     }
     // do the transfer
-    common_hal_digitalio_digitalinout_switch_to_output(self, args[ARG_value].u_bool, drive_mode);
+    digitalinout_result_t result = common_hal_digitalio_digitalinout_switch_to_output(self, args[ARG_value].u_bool, drive_mode);
+    if (result == DIGITALINOUT_INPUT_ONLY) {
+        mp_raise_NotImplementedError(translate("Pin is input only"));
+    }
     return mp_const_none;
 }
 MP_DEFINE_CONST_FUN_OBJ_KW(digitalio_digitalinout_switch_to_output_obj, 1, digitalio_digitalinout_switch_to_output);
@@ -207,7 +210,10 @@ STATIC mp_obj_t digitalio_digitalinout_obj_set_direction(mp_obj_t self_in, mp_ob
     if (value == &digitalio_direction_input_obj) {
         common_hal_digitalio_digitalinout_switch_to_input(self, PULL_NONE);
     } else if (value == &digitalio_direction_output_obj) {
-        common_hal_digitalio_digitalinout_switch_to_output(self, false, DRIVE_MODE_PUSH_PULL);
+        digitalinout_result_t result = common_hal_digitalio_digitalinout_switch_to_output(self, false, DRIVE_MODE_PUSH_PULL);
+        if (result == DIGITALINOUT_INPUT_ONLY) {
+            mp_raise_NotImplementedError(translate("Pin is input only"));
+        }
     } else {
         mp_raise_ValueError(translate("Invalid direction."));
     }
diff --git a/shared-bindings/digitalio/DigitalInOut.h b/shared-bindings/digitalio/DigitalInOut.h
index eee0d5801..dd6f088ab 100644
--- a/shared-bindings/digitalio/DigitalInOut.h
+++ b/shared-bindings/digitalio/DigitalInOut.h
@@ -37,18 +37,19 @@ extern const mp_obj_type_t digitalio_digitalinout_type;
 
 typedef enum {
     DIGITALINOUT_OK,
-    DIGITALINOUT_PIN_BUSY
+    DIGITALINOUT_PIN_BUSY,
+    DIGITALINOUT_INPUT_ONLY
 } digitalinout_result_t;
 
 digitalinout_result_t common_hal_digitalio_digitalinout_construct(digitalio_digitalinout_obj_t* self, const mcu_pin_obj_t* pin);
 void common_hal_digitalio_digitalinout_deinit(digitalio_digitalinout_obj_t* self);
 bool common_hal_digitalio_digitalinout_deinited(digitalio_digitalinout_obj_t* self);
 void common_hal_digitalio_digitalinout_switch_to_input(digitalio_digitalinout_obj_t* self, digitalio_pull_t pull);
-void common_hal_digitalio_digitalinout_switch_to_output(digitalio_digitalinout_obj_t* self, bool value, digitalio_drive_mode_t drive_mode);
+digitalinout_result_t common_hal_digitalio_digitalinout_switch_to_output(digitalio_digitalinout_obj_t* self, bool value, digitalio_drive_mode_t drive_mode);
 digitalio_direction_t common_hal_digitalio_digitalinout_get_direction(digitalio_digitalinout_obj_t* self);
 void common_hal_digitalio_digitalinout_set_value(digitalio_digitalinout_obj_t* self, bool value);
 bool common_hal_digitalio_digitalinout_get_value(digitalio_digitalinout_obj_t* self);
-void common_hal_digitalio_digitalinout_set_drive_mode(digitalio_digitalinout_obj_t* self, digitalio_drive_mode_t drive_mode);
+digitalinout_result_t common_hal_digitalio_digitalinout_set_drive_mode(digitalio_digitalinout_obj_t* self, digitalio_drive_mode_t drive_mode);
 digitalio_drive_mode_t common_hal_digitalio_digitalinout_get_drive_mode(digitalio_digitalinout_obj_t* self);
 void common_hal_digitalio_digitalinout_set_pull(digitalio_digitalinout_obj_t* self, digitalio_pull_t pull);
 digitalio_pull_t common_hal_digitalio_digitalinout_get_pull(digitalio_digitalinout_obj_t* self);