--- zzzz-none-000/linux-4.4.271/include/linux/ppp_channel.h	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/include/linux/ppp_channel.h	2023-04-19 10:22:30.000000000 +0000
@@ -1,3 +1,19 @@
+/*
+ **************************************************************************
+ * Copyright (c) 2016, The Linux Foundation.  All rights reserved.
+ * Permission to use, copy, modify, and/or distribute this software for
+ * any purpose with or without fee is hereby granted, provided that the
+ * above copyright notice and this permission notice appear in all copies.
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+ * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ **************************************************************************
+ */
+
 #ifndef _PPP_CHANNEL_H_
 #define _PPP_CHANNEL_H_
 /*
@@ -23,6 +39,12 @@
 #include <linux/skbuff.h>
 #include <linux/poll.h>
 #include <net/net_namespace.h>
+#include <linux/ppp_defs.h>
+#include <linux/notifier.h>
+
+/* PPP channel connection event types */
+#define PPP_CHANNEL_DISCONNECT	0
+#define PPP_CHANNEL_CONNECT	1
 
 struct ppp_channel;
 
@@ -32,6 +54,16 @@
 	int	(*start_xmit)(struct ppp_channel *, struct sk_buff *);
 	/* Handle an ioctl call that has come in via /dev/ppp. */
 	int	(*ioctl)(struct ppp_channel *, unsigned int, unsigned long);
+	/* Get channel protocol type, one of PX_PROTO_XYZ or specific to
+	 * the channel subtype
+	 */
+	int (*get_channel_protocol)(struct ppp_channel *);
+	/* Get channel protocol version */
+	int (*get_channel_protocol_ver)(struct ppp_channel *);
+	/* Hold the channel from being destroyed */
+	void (*hold)(struct ppp_channel *);
+	/* Release hold on the channel */
+	void (*release)(struct ppp_channel *);
 };
 
 struct ppp_channel {
@@ -46,6 +78,54 @@
 };
 
 #ifdef __KERNEL__
+/* Call this to obtain the underlying protocol of the PPP channel,
+ * e.g. PX_PROTO_OE
+ */
+extern int ppp_channel_get_protocol(struct ppp_channel *);
+
+/* Call this get protocol version */
+extern int ppp_channel_get_proto_version(struct ppp_channel *);
+
+/* Call this to hold a channel */
+extern bool ppp_channel_hold(struct ppp_channel *);
+
+/* Call this to release a hold you have upon a channel */
+extern void ppp_channel_release(struct ppp_channel *);
+
+/* Release hold on PPP channels */
+extern void ppp_release_channels(struct ppp_channel *channels[],
+				 unsigned int chan_sz);
+
+/* Hold PPP channels for the PPP device */
+extern int ppp_hold_channels(struct net_device *dev,
+			     struct ppp_channel *channels[],
+			     unsigned int chan_sz);
+/* Test if ppp xmit lock is locked */
+extern bool ppp_is_xmit_locked(struct net_device *dev);
+
+/* Hold PPP channels for the PPP device */
+extern int __ppp_hold_channels(struct net_device *dev,
+			       struct ppp_channel *channels[],
+			       unsigned int chan_sz);
+
+/* Test if the ppp device is a multi-link ppp device */
+extern int ppp_is_multilink(struct net_device *dev);
+
+/* Test if compression is enabled */
+extern bool ppp_is_cp_enabled(struct net_device *dev);
+
+/* Test if the ppp device is a multi-link ppp device */
+extern int __ppp_is_multilink(struct net_device *dev);
+
+/* Update statistics of the PPP net_device by incrementing related
+ * statistics field value with corresponding parameter
+ */
+extern void ppp_update_stats(struct net_device *dev, unsigned long rx_packets,
+			     unsigned long rx_bytes, unsigned long tx_packets,
+			     unsigned long tx_bytes, unsigned long rx_errors,
+			     unsigned long tx_errors, unsigned long rx_dropped,
+			     unsigned long tx_dropped);
+
 /* Called by the channel when it can send some more data. */
 extern void ppp_output_wakeup(struct ppp_channel *);
 
@@ -69,12 +149,21 @@
 /* Get the channel number for a channel */
 extern int ppp_channel_index(struct ppp_channel *);
 
+/* Get the device index  associated with a channel, or 0, if none */
+extern int ppp_dev_index(struct ppp_channel *);
+
 /* Get the unit number associated with a channel, or -1 if none */
 extern int ppp_unit_number(struct ppp_channel *);
 
 /* Get the device name associated with a channel, or NULL if none */
 extern char *ppp_dev_name(struct ppp_channel *);
 
+/* Register the PPP channel connect notifier */
+extern void ppp_channel_connection_register_notify(struct notifier_block *nb);
+
+/* Unregister the PPP channel connect notifier */
+extern void ppp_channel_connection_unregister_notify(struct notifier_block *nb);
+
 /*
  * SMP locking notes:
  * The channel code must ensure that when it calls ppp_unregister_channel,