1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Support for generic time stamping devices on MII buses.
4  * Copyright (C) 2018 Richard Cochran <[email protected]>
5  */
6 #ifndef _LINUX_MII_TIMESTAMPER_H
7 #define _LINUX_MII_TIMESTAMPER_H
8 
9 #include <linux/device.h>
10 #include <linux/ethtool.h>
11 #include <linux/skbuff.h>
12 #include <linux/net_tstamp.h>
13 
14 struct phy_device;
15 
16 /**
17  * struct mii_timestamper - Callback interface to MII time stamping devices.
18  *
19  * @rxtstamp:	Requests a Rx timestamp for 'skb'.  If the skb is accepted,
20  *		the MII time stamping device promises to deliver it using
21  *		netif_rx() as soon as a timestamp becomes available. One of
22  *		the PTP_CLASS_ values is passed in 'type'.  The function
23  *		must return true if the skb is accepted for delivery.
24  *
25  * @txtstamp:	Requests a Tx timestamp for 'skb'.  The MII time stamping
26  *		device promises to deliver it using skb_complete_tx_timestamp()
27  *		as soon as a timestamp becomes available. One of the PTP_CLASS_
28  *		values is passed in 'type'.
29  *
30  * @hwtstamp:	Handles SIOCSHWTSTAMP ioctl for hardware time stamping.
31  *
32  * @link_state: Allows the device to respond to changes in the link
33  *		state.  The caller invokes this function while holding
34  *		the phy_device mutex.
35  *
36  * @ts_info:	Handles ethtool queries for hardware time stamping.
37  * @device:	Remembers the device to which the instance belongs.
38  *
39  * Drivers for PHY time stamping devices should embed their
40  * mii_timestamper within a private structure, obtaining a reference
41  * to it using container_of().
42  *
43  * Drivers for non-PHY time stamping devices should return a pointer
44  * to a mii_timestamper from the probe_channel() callback of their
45  * mii_timestamping_ctrl interface.
46  */
47 struct mii_timestamper {
48 	bool (*rxtstamp)(struct mii_timestamper *mii_ts,
49 			 struct sk_buff *skb, int type);
50 
51 	void (*txtstamp)(struct mii_timestamper *mii_ts,
52 			 struct sk_buff *skb, int type);
53 
54 	int  (*hwtstamp)(struct mii_timestamper *mii_ts,
55 			 struct kernel_hwtstamp_config *kernel_config,
56 			 struct netlink_ext_ack *extack);
57 
58 	void (*link_state)(struct mii_timestamper *mii_ts,
59 			   struct phy_device *phydev);
60 
61 	int  (*ts_info)(struct mii_timestamper *mii_ts,
62 			struct ethtool_ts_info *ts_info);
63 
64 	struct device *device;
65 };
66 
67 /**
68  * struct mii_timestamping_ctrl - MII time stamping controller interface.
69  *
70  * @probe_channel:	Callback into the controller driver announcing the
71  *			presence of the 'port' channel.  The 'device' field
72  *			had been passed to register_mii_tstamp_controller().
73  *			The driver must return either a pointer to a valid
74  *			MII timestamper instance or PTR_ERR.
75  *
76  * @release_channel:	Releases an instance obtained via .probe_channel.
77  */
78 struct mii_timestamping_ctrl {
79 	struct mii_timestamper *(*probe_channel)(struct device *device,
80 						 unsigned int port);
81 	void (*release_channel)(struct device *device,
82 				struct mii_timestamper *mii_ts);
83 };
84 
85 #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
86 
87 int register_mii_tstamp_controller(struct device *device,
88 				   struct mii_timestamping_ctrl *ctrl);
89 
90 void unregister_mii_tstamp_controller(struct device *device);
91 
92 struct mii_timestamper *register_mii_timestamper(struct device_node *node,
93 						 unsigned int port);
94 
95 void unregister_mii_timestamper(struct mii_timestamper *mii_ts);
96 
97 #else
98 
99 static inline
100 int register_mii_tstamp_controller(struct device *device,
101 				   struct mii_timestamping_ctrl *ctrl)
102 {
103 	return -EOPNOTSUPP;
104 }
105 
106 static inline void unregister_mii_tstamp_controller(struct device *device)
107 {
108 }
109 
110 static inline
111 struct mii_timestamper *register_mii_timestamper(struct device_node *node,
112 						 unsigned int port)
113 {
114 	return NULL;
115 }
116 
117 static inline void unregister_mii_timestamper(struct mii_timestamper *mii_ts)
118 {
119 }
120 
121 #endif
122 
123 #endif
124