diff --git a/src/common/i2c.c b/src/common/i2c.c
index d1ccd69..5fb0eef 100644
--- a/src/common/i2c.c
+++ b/src/common/i2c.c
@@ -2,7 +2,7 @@
 
 #include <common/i2c.h>
 
-int i2c_recv(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) {
+int i2c_recv(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) __reentrant {
     int res = 0;
 
     res = i2c_start(i2c, addr, true);
@@ -16,7 +16,7 @@ int i2c_recv(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) {
 	return res;
 }
 
-int i2c_send(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) {
+int i2c_send(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) __reentrant {
     int res = 0;
 
     res = i2c_start(i2c, addr, false);
@@ -30,7 +30,7 @@ int i2c_send(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) {
 	return res;
 }
 
-int i2c_get(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length) {
+int i2c_get(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length) __reentrant {
     int res = 0;
 
     res = i2c_start(i2c, addr, false);
@@ -42,7 +42,7 @@ int i2c_get(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int leng
     return i2c_recv(i2c, addr, data, length);
 }
 
-int i2c_set(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length) {
+int i2c_set(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length) __reentrant {
     int res = 0;
 
     res = i2c_start(i2c, addr, false);
diff --git a/src/common/include/common/i2c.h b/src/common/include/common/i2c.h
index e89951f..ca7cfc6 100644
--- a/src/common/include/common/i2c.h
+++ b/src/common/include/common/i2c.h
@@ -11,30 +11,30 @@ struct I2C;
 
 // Start i2c transaction
 // Must be defined by arch, board, or ec
-int i2c_start(struct I2C * i2c, uint8_t addr, bool read);
+int i2c_start(struct I2C * i2c, uint8_t addr, bool read) __reentrant;
 
 // Stop i2c transaction
 // Must be defined by arch, board, or ec
-void i2c_stop(struct I2C * i2c);
+void i2c_stop(struct I2C * i2c) __reentrant;
 
 // Send a byte on i2c bus
 // Must be defined by arch, board, or ec
-int i2c_write(struct I2C * i2c, uint8_t * data, int length);
+int i2c_write(struct I2C * i2c, uint8_t * data, int length) __reentrant;
 
 // Read bytes from bus
 // Must be defined by arch, board, or ec
-int i2c_read(struct I2C * i2c, uint8_t * data, int length);
+int i2c_read(struct I2C * i2c, uint8_t * data, int length) __reentrant;
 
 // Read multiple bytes from address in one transaction
-int i2c_recv(struct I2C * i2c, uint8_t addr, uint8_t* data, int length);
+int i2c_recv(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) __reentrant;
 
 // Write multiple bytes to address in one transaction
-int i2c_send(struct I2C * i2c, uint8_t addr, uint8_t* data, int length);
+int i2c_send(struct I2C * i2c, uint8_t addr, uint8_t* data, int length) __reentrant;
 
 // Read multiple bytes from a register in one transaction
-int i2c_get(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length);
+int i2c_get(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length) __reentrant;
 
 // Write multiple bytes to a register in one transaction
-int i2c_set(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length);
+int i2c_set(struct I2C * i2c, uint8_t addr, uint8_t reg, uint8_t* data, int length) __reentrant;
 
 #endif // _COMMON_I2C_H
diff --git a/src/ec/it5570e/i2c.c b/src/ec/it5570e/i2c.c
index 1ee8813..58be800 100644
--- a/src/ec/it5570e/i2c.c
+++ b/src/ec/it5570e/i2c.c
@@ -55,7 +55,7 @@ void i2c_reset(struct I2C * i2c, bool kill) {
     *(i2c->hoctl2) = 0;
 }
 
-int i2c_start(struct I2C * i2c, uint8_t addr, bool read) {
+int i2c_start(struct I2C * i2c, uint8_t addr, bool read) __reentrant {
     // If we are already in a transaction
     if (*(i2c->hosta) & HOSTA_BYTE_DONE) {
         // If we are switching direction
@@ -151,10 +151,10 @@ static int i2c_transaction(struct I2C * i2c, uint8_t * data, int length, bool re
     return i;
 }
 
-int i2c_read(struct I2C * i2c, uint8_t * data, int length) {
+int i2c_read(struct I2C * i2c, uint8_t * data, int length) __reentrant {
     return i2c_transaction(i2c, data, length, true);
 }
 
-int i2c_write(struct I2C * i2c, uint8_t * data, int length) {
+int i2c_write(struct I2C * i2c, uint8_t * data, int length) __reentrant {
     return i2c_transaction(i2c, data, length, false);
 }
diff --git a/src/ec/it8587e/i2c.c b/src/ec/it8587e/i2c.c
index ebbad06..a403940 100644
--- a/src/ec/it8587e/i2c.c
+++ b/src/ec/it8587e/i2c.c
@@ -47,7 +47,7 @@ void i2c_reset(struct I2C * i2c, bool kill) {
     *(i2c->hoctl2) = 0;
 }
 
-int i2c_start(struct I2C * i2c, uint8_t addr, bool read) {
+int i2c_start(struct I2C * i2c, uint8_t addr, bool read) __reentrant {
     // If we are already in a transaction
     if (*(i2c->hosta) & HOSTA_BYTE_DONE) {
         // If we are switching direction
@@ -143,10 +143,10 @@ static int i2c_transaction(struct I2C * i2c, uint8_t * data, int length, bool re
     return i;
 }
 
-int i2c_read(struct I2C * i2c, uint8_t * data, int length) {
+int i2c_read(struct I2C * i2c, uint8_t * data, int length) __reentrant {
     return i2c_transaction(i2c, data, length, true);
 }
 
-int i2c_write(struct I2C * i2c, uint8_t * data, int length) {
+int i2c_write(struct I2C * i2c, uint8_t * data, int length) __reentrant {
     return i2c_transaction(i2c, data, length, false);
 }