soc: qcom: sanity check for aon_com_dev node

Add sanity check to handle write operation on
aon_com_dev node from userspace when driver
is not initialized.

Change-Id: I1bd1fb94ee5b59ff113f8e359c303a2dd1f47430
Signed-off-by: Praveen koya <quic_pkoya@quicinc.com>

drivers/soc/qcom/slatecom_interface.c

@@ -1051,10 +1051,15 @@ static ssize_t slatecom_char_write(struct file *f, const char __user *buf,
 	unsigned char qcli_cmnd;
 	uint32_t opcode;
 	int ret = 0;
-	struct slatedaemon_priv *dev = container_of(slatecom_intf_drv,
+	struct slatedaemon_priv *dev = NULL;
+
+	if (!slatecom_intf_drv) {
+		pr_err("Invalid use-case, slatecom driver is not ready\n");
+		return -EINVAL;
+	}
+	dev = container_of(slatecom_intf_drv,
 					struct slatedaemon_priv,
 					lhndl);
-
 	if (copy_from_user(&qcli_cmnd, buf, sizeof(unsigned char)))
 		return -EFAULT;