From 5a184c19b21bcc946697b8c83f6a43b6200aa02f Mon Sep 17 00:00:00 2001
From: Howard Su <howard0su@gmail.com>
Date: Sun, 28 Feb 2021 16:42:27 +0800
Subject: [PATCH] Return when i2c transfer 0 messages

msg->flags is accessed without proper intialized msg variable.
---
 components/drivers/i2c/i2c-bit-ops.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/components/drivers/i2c/i2c-bit-ops.c b/components/drivers/i2c/i2c-bit-ops.c
index 96af567a1e..3a9b4efeb3 100644
--- a/components/drivers/i2c/i2c-bit-ops.c
+++ b/components/drivers/i2c/i2c-bit-ops.c
@@ -375,6 +375,8 @@ static rt_size_t i2c_bit_xfer(struct rt_i2c_bus_device *bus,
     rt_int32_t i, ret;
     rt_uint16_t ignore_nack;
 
+    if (num == 0) return 0;
+
     for (i = 0; i < num; i++)
     {
         msg = &msgs[i];