From 87c9a8a8fa15854ce4cede7af709def2259f5885 Mon Sep 17 00:00:00 2001
From: me-no-dev <hristo@espressif.com>
Date: Sun, 17 May 2020 14:54:41 +0300
Subject: [PATCH] some i2c fixes

---
 cores/esp32/esp32-hal-i2c.c | 26 ++++++++++++++++++++------
 libraries/Wire/src/Wire.cpp |  8 +++++++-
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/cores/esp32/esp32-hal-i2c.c b/cores/esp32/esp32-hal-i2c.c
index 9ebf7261..a3ae8219 100644
--- a/cores/esp32/esp32-hal-i2c.c
+++ b/cores/esp32/esp32-hal-i2c.c
@@ -1792,13 +1792,25 @@ struct i2c_struct_t {
 	i2c_port_t num;
 };
 
+static i2c_t * i2c_ports[2] = {NULL, NULL};
+
 i2c_t * i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t clk_speed){
-    i2c_t * out = (i2c_t*)malloc(sizeof(i2c_t));
-    if(out == NULL){
-        log_e("malloc failed");
-        return NULL;
-    }
-    out->num = (i2c_port_t)i2c_num;
+	if(i2c_num >= 2){
+		return NULL;
+	}
+	i2c_t * out = NULL;
+	if(i2c_ports[i2c_num] == NULL){
+		out = (i2c_t*)malloc(sizeof(i2c_t));
+		if(out == NULL){
+			log_e("malloc failed");
+			return NULL;
+		}
+		out->num = (i2c_port_t)i2c_num;
+		i2c_ports[i2c_num] = out;
+	} else {
+		out = i2c_ports[i2c_num];
+		i2c_driver_delete((i2c_port_t)i2c_num);
+	}
 
     i2c_config_t conf;
     conf.mode = I2C_MODE_MASTER;
@@ -1811,12 +1823,14 @@ i2c_t * i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t clk_speed){
     if (ret != ESP_OK) {
         log_e("i2c_param_config failed");
         free(out);
+        i2c_ports[i2c_num] = NULL;
         return NULL;
     }
     ret = i2c_driver_install(out->num, conf.mode, 0, 0, 0);
     if (ret != ESP_OK) {
         log_e("i2c_driver_install failed");
         free(out);
+        i2c_ports[i2c_num] = NULL;
         return NULL;
     }
     return out;
diff --git a/libraries/Wire/src/Wire.cpp b/libraries/Wire/src/Wire.cpp
index 3fbd0eb0..3acea70a 100644
--- a/libraries/Wire/src/Wire.cpp
+++ b/libraries/Wire/src/Wire.cpp
@@ -107,7 +107,7 @@ bool TwoWire::begin(int sdaPin, int sclPin, uint32_t frequency)
 
     sda = sdaPin;
     scl = sclPin;
-    i2c = i2cInit(num, sdaPin, sclPin, frequency);
+    i2c = i2cInit(num, sda, scl, frequency);
     if(!i2c) {
         return false;
     }
@@ -129,6 +129,12 @@ uint16_t TwoWire::getTimeOut()
 
 void TwoWire::setClock(uint32_t frequency)
 {
+#if CONFIG_IDF_TARGET_ESP32S2
+    i2c = i2cInit(num, sda, scl, frequency);
+    if(!i2c) {
+        return;
+    }
+#endif
     i2cSetFrequency(i2c, frequency);
 }