From 99a3750a2cfd1da8cdd266ca9a0367f0c3a54092 Mon Sep 17 00:00:00 2001
From: Christian Walther <cwalther@gmx.ch>
Date: Sat, 24 Oct 2020 17:50:11 +0200
Subject: [PATCH] Fix lost board.SPI and board.I2C after explicitly deiniting
 them.

After calling board.SPI().deinit(), calling board.SPI() again would return the unusable deinited object and there was no way of getting it back into an initialized state until the end of the session.
---
 shared-bindings/board/__init__.c | 10 ++++++++--
 shared-module/board/__init__.c   | 10 ++++------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/shared-bindings/board/__init__.c b/shared-bindings/board/__init__.c
index 6837fc41c2..717698408a 100644
--- a/shared-bindings/board/__init__.c
+++ b/shared-bindings/board/__init__.c
@@ -28,6 +28,12 @@
 #include "py/runtime.h"
 
 #include "shared-bindings/board/__init__.h"
+#if BOARD_I2C
+#include "shared-bindings/busio/I2C.h"
+#endif
+#if BOARD_SPI
+#include "shared-bindings/busio/SPI.h"
+#endif
 
 //| """Board specific pin names
 //|
@@ -45,7 +51,7 @@
 #if BOARD_I2C
 mp_obj_t board_i2c(void) {
     mp_obj_t singleton = common_hal_board_get_i2c();
-    if (singleton != NULL) {
+    if (singleton != NULL && !common_hal_busio_i2c_deinited(singleton)) {
         return singleton;
     }
     assert_pin_free(DEFAULT_I2C_BUS_SDA);
@@ -69,7 +75,7 @@ MP_DEFINE_CONST_FUN_OBJ_0(board_i2c_obj, board_i2c);
 #if BOARD_SPI
 mp_obj_t board_spi(void) {
     mp_obj_t singleton = common_hal_board_get_spi();
-    if (singleton != NULL) {
+    if (singleton != NULL && !common_hal_busio_spi_deinited(singleton)) {
         return singleton;
     }
     assert_pin_free(DEFAULT_SPI_BUS_SCK);
diff --git a/shared-module/board/__init__.c b/shared-module/board/__init__.c
index 967b430d2b..2f1c34e565 100644
--- a/shared-module/board/__init__.c
+++ b/shared-module/board/__init__.c
@@ -55,9 +55,8 @@ mp_obj_t common_hal_board_get_i2c(void) {
 }
 
 mp_obj_t common_hal_board_create_i2c(void) {
-    if (i2c_singleton != NULL) {
-        return i2c_singleton;
-    }
+    // All callers have either already verified this or come so early that it can't be otherwise.
+    assert(i2c_singleton == NULL || common_hal_busio_i2c_deinited(i2c_singleton));
     busio_i2c_obj_t *self = &i2c_obj;
     self->base.type = &busio_i2c_type;
 
@@ -79,9 +78,8 @@ mp_obj_t common_hal_board_get_spi(void) {
 }
 
 mp_obj_t common_hal_board_create_spi(void) {
-    if (spi_singleton != NULL) {
-        return spi_singleton;
-    }
+    // All callers have either already verified this or come so early that it can't be otherwise.
+    assert(spi_singleton == NULL || common_hal_busio_spi_deinited(spi_singleton));
     busio_spi_obj_t *self = &spi_obj;
     self->base.type = &busio_spi_type;