From 5bd4decad1de4a159f09714ae4eb8f653e706df0 Mon Sep 17 00:00:00 2001
From: Omar Chebib <omar.chebib@espressif.com>
Date: Fri, 11 Mar 2022 11:25:39 +0800
Subject: [PATCH] I2C: Read transactions, without a STOP, won't panic anymore

* Closes https://github.com/espressif/esp-idf/issues/8548
---
 components/driver/i2c.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/components/driver/i2c.c b/components/driver/i2c.c
index bcd25abd9b..620b87eacd 100644
--- a/components/driver/i2c.c
+++ b/components/driver/i2c.c
@@ -1310,7 +1310,9 @@ static void IRAM_ATTR i2c_master_cmd_begin_static(i2c_port_t i2c_num)
             p_i2c->cmd_idx = 0;
         } else {
             p_i2c->cmd_link.head = p_i2c->cmd_link.head->next;
-            p_i2c->cmd_link.head->cmd.bytes_used = 0;
+            if (p_i2c->cmd_link.head != NULL) {
+                p_i2c->cmd_link.head->cmd.bytes_used = 0;
+            }
         }
     } else if ((p_i2c->status == I2C_STATUS_ACK_ERROR)
                || (p_i2c->status == I2C_STATUS_TIMEOUT)) {