From ff9a13534403d6af55e7518ef39546b60cb12da4 Mon Sep 17 00:00:00 2001
From: EmanuelFeru <aerdronix@gmail.com>
Date: Sun, 6 Dec 2020 17:39:36 +0100
Subject: [PATCH] Added i2c timeout

- i2c timeout to avoid getting stuck in while loop
---
 Src/i2c_it.c |  2 ++
 Src/setup.c  |  8 ++++----
 Src/util.c   | 16 +++++++++++-----
 3 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/Src/i2c_it.c b/Src/i2c_it.c
index dbfa270..c25016a 100644
--- a/Src/i2c_it.c
+++ b/Src/i2c_it.c
@@ -198,6 +198,7 @@ void I2C0_ErrorIRQ_Handler(void)
     if(i2c_interrupt_flag_get(I2C0, I2C_INT_FLAG_PECERR)){
         i2c_interrupt_flag_clear(I2C0, I2C_INT_FLAG_PECERR);
     }
+
     /* disable the error interrupt */
     i2c_interrupt_disable(I2C0,I2C_INT_ERR | I2C_INT_BUF | I2C_INT_EV);
 }
@@ -365,6 +366,7 @@ void I2C1_ErrorIRQ_Handler(void)
     if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_PECERR)){
         i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_PECERR);
     }
+
     /* disable the error interrupt */
     i2c_interrupt_disable(I2C1,I2C_INT_ERR | I2C_INT_BUF | I2C_INT_EV);
 }
diff --git a/Src/setup.c b/Src/setup.c
index f758c85..fd3b0a9 100644
--- a/Src/setup.c
+++ b/Src/setup.c
@@ -342,12 +342,12 @@ void i2c_nvic_config(void)
     /* configure the NVIC peripheral */
     nvic_priority_group_set(NVIC_PRIGROUP_PRE1_SUB3);
 
-    nvic_irq_enable(I2C0_EV_IRQn, 0, 3);
-    nvic_irq_enable(I2C0_ER_IRQn, 0, 2);
+    nvic_irq_enable(I2C0_EV_IRQn, 0, 0);
+    nvic_irq_enable(I2C0_ER_IRQn, 0, 0);
 
     #ifdef AUX45_USE_I2C
-    nvic_irq_enable(I2C1_EV_IRQn, 0, 4);
-    nvic_irq_enable(I2C1_ER_IRQn, 0, 1);
+    nvic_irq_enable(I2C1_EV_IRQn, 0, 2);
+    nvic_irq_enable(I2C1_ER_IRQn, 0, 2);
     #endif
 }
 
diff --git a/Src/util.c b/Src/util.c
index 594f34c..dafc64a 100644
--- a/Src/util.c
+++ b/Src/util.c
@@ -570,17 +570,20 @@ int8_t i2c_writeBytes(uint8_t slaveAddr, uint8_t regAddr, uint8_t length, uint8_
     i2c_nDABytes        = length;
     i2c_nRABytes        = 1;
 
+    uint16_t i2c_timeout = 0;
+
     // enable the I2C0 interrupt
     i2c_interrupt_enable(MPU_I2C, I2C_INT_ERR | I2C_INT_BUF | I2C_INT_EV);
 
     // the master waits until the I2C bus is idle
-    while(i2c_flag_get(MPU_I2C, I2C_FLAG_I2CBSY));
+    while(i2c_flag_get(MPU_I2C, I2C_FLAG_I2CBSY) && i2c_timeout++ < 20000);
 
     // the master sends a start condition to I2C bus
     i2c_start_on_bus(MPU_I2C);
-
+    
     // Wait until all data bytes are sent/received
-    while(i2c_nDABytes > 0);
+    i2c_timeout = 0;
+    while(i2c_nDABytes > 0 && i2c_timeout++ < 20000);
 
     return i2c_status;
 
@@ -627,6 +630,8 @@ int8_t i2c_readBytes(uint8_t slaveAddr, uint8_t regAddr, uint8_t length, uint8_t
     i2c_nDABytes        = length;
     i2c_nRABytes        = 1;
 
+    uint16_t i2c_timeout = 0;
+
     // enable the I2C0 interrupt
     i2c_interrupt_enable(MPU_I2C, I2C_INT_ERR | I2C_INT_BUF | I2C_INT_EV);
 
@@ -635,13 +640,14 @@ int8_t i2c_readBytes(uint8_t slaveAddr, uint8_t regAddr, uint8_t length, uint8_t
     }
 
     // the master waits until the I2C bus is idle
-    while(i2c_flag_get(MPU_I2C, I2C_FLAG_I2CBSY));
+    while(i2c_flag_get(MPU_I2C, I2C_FLAG_I2CBSY) && i2c_timeout++ < 20000);
 
     // the master sends a start condition to I2C bus
     i2c_start_on_bus(MPU_I2C);
 
     // Wait until all data bytes are sent/received
-    while(i2c_nDABytes > 0);
+    i2c_timeout = 0;
+    while(i2c_nDABytes > 0 && i2c_timeout++ < 20000);
 
     // Return status
     return i2c_status;