Added timeout to i2c_stop operations

Fixes this issue:

http://mbed.org/users/mbed_official/code/mbed/issues/3

Author: Bogdan Marinescu

libraries/mbed/hal/i2c_api.h

@@ -34,7 +34,7 @@ enum {
 void i2c_init         (i2c_t *obj, PinName sda, PinName scl);
 void i2c_frequency    (i2c_t *obj, int hz);
 int  i2c_start        (i2c_t *obj);
-void i2c_stop         (i2c_t *obj);
+int  i2c_stop         (i2c_t *obj);
 int  i2c_read         (i2c_t *obj, int address, char *data, int length, int stop);
 int  i2c_write        (i2c_t *obj, int address, const char *data, int length, int stop);
 void i2c_reset        (i2c_t *obj);

libraries/mbed/targets/hal/Freescale/TARGET_KL25Z/i2c_api.c

@@ -96,7 +96,7 @@ int i2c_start(i2c_t *obj) {
     return 0;
 }
 
-void i2c_stop(i2c_t *obj) {
+int i2c_stop(i2c_t *obj) {
     volatile uint32_t n = 0;
     obj->i2c->C1 &= ~I2C_C1_MST_MASK;
     obj->i2c->C1 &= ~I2C_C1_TX_MASK;
@@ -107,6 +107,7 @@ void i2c_stop(i2c_t *obj) {
     // code provided with the freedom board
     for (n = 0; n < 100; n++) __NOP();
     first_read = 1;
+    return 0;
 }
 
 static int timeout_status_poll(i2c_t *obj, uint32_t mask) {

libraries/mbed/targets/hal/NXP/TARGET_LPC11UXX/i2c_api.c

@@ -124,13 +124,20 @@ inline int i2c_start(i2c_t *obj) {
     return status;
 }
 
-inline void i2c_stop(i2c_t *obj) {
+inline int i2c_stop(i2c_t *obj) {
+    int timeout = 0;
+
     // write the stop bit
     i2c_conset(obj, 0, 1, 0, 0);
     i2c_clear_SI(obj);
 
     // wait for STO bit to reset
-    while(I2C_CONSET(obj) & (1 << 4));
+    while(I2C_CONSET(obj) & (1 << 4)) {
+        timeout ++;
+        if (timeout > 100000) return 1;
+    }
+
+    return 0;
 }
 
 

libraries/mbed/targets/hal/NXP/TARGET_LPC176X/i2c_api.c

@@ -133,13 +133,20 @@ inline int i2c_start(i2c_t *obj) {
     return status;
 }
 
-inline void i2c_stop(i2c_t *obj) {
+inline int i2c_stop(i2c_t *obj) {
+    int timeout = 0;
+
     // write the stop bit
     i2c_conset(obj, 0, 1, 0, 0);
     i2c_clear_SI(obj);
 
     // wait for STO bit to reset
-    while(I2C_CONSET(obj) & (1 << 4));
+    while(I2C_CONSET(obj) & (1 << 4)) {
+        timeout ++;
+        if (timeout > 100000) return 1;
+    }
+
+    return 0;
 }
 
 static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) {

libraries/mbed/targets/hal/NXP/TARGET_LPC23XX/i2c_api.c

@@ -133,13 +133,20 @@ inline int i2c_start(i2c_t *obj) {
     return status;
 }
 
-inline void i2c_stop(i2c_t *obj) {
+inline int i2c_stop(i2c_t *obj) {
+    int timeout = 0;
+
     // write the stop bit
     i2c_conset(obj, 0, 1, 0, 0);
     i2c_clear_SI(obj);
 
     // wait for STO bit to reset
-    while (I2C_CONSET(obj) & (1 << 4));
+    while (I2C_CONSET(obj) & (1 << 4)) {
+        timeout ++;
+        if (timeout > 100000) return 1;
+    }
+
+    return 0;
 }
 
 static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) {

libraries/mbed/targets/hal/NXP/TARGET_LPC408X/i2c_api.c

@@ -144,13 +144,20 @@ inline int i2c_start(i2c_t *obj) {
     return status;
 }
 
-inline void i2c_stop(i2c_t *obj) {
+inline int i2c_stop(i2c_t *obj) {
+    int timeout = 0;
+
     // write the stop bit
     i2c_conset(obj, 0, 1, 0, 0);
     i2c_clear_SI(obj);
 
     // wait for STO bit to reset
-    while(I2C_CONSET(obj) & (1 << 4));
+    while(I2C_CONSET(obj) & (1 << 4)) {
+        timeout ++;
+        if (timeout > 100000) return 1;
+    }
+
+    return 0;
 }
 
 

libraries/mbed/targets/hal/NXP/TARGET_LPC81X/i2c_api.c

@@ -87,9 +87,16 @@ inline int i2c_start(i2c_t *obj) {
     return status;
 }
 
-inline void i2c_stop(i2c_t *obj) {
+inline int i2c_stop(i2c_t *obj) {
+    int timeout = 0;
+
     obj->i2c->MSTCTL = (1 << 2) | (1 << 0);
-    while ((obj->i2c->STAT & ((1 << 0) | (7 << 1))) != ((1 << 0) | (0 << 1)));
+    while ((obj->i2c->STAT & ((1 << 0) | (7 << 1))) != ((1 << 0) | (0 << 1))) {
+        timeout ++;
+        if (timeout > 100000) return 1;
+    }
+
+    return 0;
 }
 
 

libraries/mbed/targets/hal/STM/TARGET_STM32F4XX/i2c_api.c

@@ -163,9 +163,10 @@ inline int i2c_start(i2c_t *obj) {
     return 0;
 }
 
-inline void i2c_stop(i2c_t *obj) {
+inline int i2c_stop(i2c_t *obj) {
     // Generate the stop condition
     obj->i2c->CR1 |= I2C_CR1_STOP;
+    return 0;
 }