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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * linux/can/dev.h
4 *
5 * Definitions for the CAN network device driver interface
6 *
7 * Copyright (C) 2006 Andrey Volkov <avolkov@varma-el.com>
8 * Varma Electronics Oy
9 *
10 * Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com>
11 *
12 */
13
14#ifndef _CAN_DEV_H
15#define _CAN_DEV_H
16
17#include <linux/can.h>
18#include <linux/can/bittiming.h>
19#include <linux/can/error.h>
20#include <linux/can/length.h>
21#include <linux/can/netlink.h>
22#include <linux/can/skb.h>
23#include <linux/netdevice.h>
24
25/*
26 * CAN mode
27 */
28enum can_mode {
29 CAN_MODE_STOP = 0,
30 CAN_MODE_START,
31 CAN_MODE_SLEEP
32};
33
34enum can_termination_gpio {
35 CAN_TERMINATION_GPIO_DISABLED = 0,
36 CAN_TERMINATION_GPIO_ENABLED,
37 CAN_TERMINATION_GPIO_MAX,
38};
39
40/*
41 * CAN common private data
42 */
43struct can_priv {
44 struct net_device *dev;
45 struct can_device_stats can_stats;
46
47 const struct can_bittiming_const *bittiming_const,
48 *data_bittiming_const;
49 struct can_bittiming bittiming, data_bittiming;
50 const struct can_tdc_const *tdc_const;
51 struct can_tdc tdc;
52
53 unsigned int bitrate_const_cnt;
54 const u32 *bitrate_const;
55 const u32 *data_bitrate_const;
56 unsigned int data_bitrate_const_cnt;
57 u32 bitrate_max;
58 struct can_clock clock;
59
60 unsigned int termination_const_cnt;
61 const u16 *termination_const;
62 u16 termination;
63 struct gpio_desc *termination_gpio;
64 u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX];
65
66 unsigned int echo_skb_max;
67 struct sk_buff **echo_skb;
68
69 enum can_state state;
70
71 /* CAN controller features - see include/uapi/linux/can/netlink.h */
72 u32 ctrlmode; /* current options setting */
73 u32 ctrlmode_supported; /* options that can be modified by netlink */
74
75 int restart_ms;
76 struct delayed_work restart_work;
77
78 int (*do_set_bittiming)(struct net_device *dev);
79 int (*do_set_data_bittiming)(struct net_device *dev);
80 int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
81 int (*do_set_termination)(struct net_device *dev, u16 term);
82 int (*do_get_state)(const struct net_device *dev,
83 enum can_state *state);
84 int (*do_get_berr_counter)(const struct net_device *dev,
85 struct can_berr_counter *bec);
86 int (*do_get_auto_tdcv)(const struct net_device *dev, u32 *tdcv);
87};
88
89static inline bool can_tdc_is_enabled(const struct can_priv *priv)
90{
91 return !!(priv->ctrlmode & CAN_CTRLMODE_TDC_MASK);
92}
93
94/*
95 * can_get_relative_tdco() - TDCO relative to the sample point
96 *
97 * struct can_tdc::tdco represents the absolute offset from TDCV. Some
98 * controllers use instead an offset relative to the Sample Point (SP)
99 * such that:
100 *
101 * SSP = TDCV + absolute TDCO
102 * = TDCV + SP + relative TDCO
103 *
104 * -+----------- one bit ----------+-- TX pin
105 * |<--- Sample Point --->|
106 *
107 * --+----------- one bit ----------+-- RX pin
108 * |<-------- TDCV -------->|
109 * |<------------------------>| absolute TDCO
110 * |<--- Sample Point --->|
111 * | |<->| relative TDCO
112 * |<------------- Secondary Sample Point ------------>|
113 */
114static inline s32 can_get_relative_tdco(const struct can_priv *priv)
115{
116 const struct can_bittiming *dbt = &priv->data_bittiming;
117 s32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg +
118 dbt->phase_seg1) * dbt->brp;
119
120 return (s32)priv->tdc.tdco - sample_point_in_tc;
121}
122
123/* helper to define static CAN controller features at device creation time */
124static inline int __must_check can_set_static_ctrlmode(struct net_device *dev,
125 u32 static_mode)
126{
127 struct can_priv *priv = netdev_priv(dev);
128
129 /* alloc_candev() succeeded => netdev_priv() is valid at this point */
130 if (priv->ctrlmode_supported & static_mode) {
131 netdev_warn(dev,
132 "Controller features can not be supported and static at the same time\n");
133 return -EINVAL;
134 }
135 priv->ctrlmode = static_mode;
136
137 /* override MTU which was set by default in can_setup()? */
138 if (static_mode & CAN_CTRLMODE_FD)
139 dev->mtu = CANFD_MTU;
140
141 return 0;
142}
143
144static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
145{
146 return priv->ctrlmode & ~priv->ctrlmode_supported;
147}
148
149void can_setup(struct net_device *dev);
150
151struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
152 unsigned int txqs, unsigned int rxqs);
153#define alloc_candev(sizeof_priv, echo_skb_max) \
154 alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1)
155#define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \
156 alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count)
157void free_candev(struct net_device *dev);
158
159/* a candev safe wrapper around netdev_priv */
160struct can_priv *safe_candev_priv(struct net_device *dev);
161
162int open_candev(struct net_device *dev);
163void close_candev(struct net_device *dev);
164int can_change_mtu(struct net_device *dev, int new_mtu);
165
166int register_candev(struct net_device *dev);
167void unregister_candev(struct net_device *dev);
168
169int can_restart_now(struct net_device *dev);
170void can_bus_off(struct net_device *dev);
171
172const char *can_get_state_str(const enum can_state state);
173void can_change_state(struct net_device *dev, struct can_frame *cf,
174 enum can_state tx_state, enum can_state rx_state);
175
176#ifdef CONFIG_OF
177void of_can_transceiver(struct net_device *dev);
178#else
179static inline void of_can_transceiver(struct net_device *dev) { }
180#endif
181
182extern struct rtnl_link_ops can_link_ops;
183int can_netlink_register(void);
184void can_netlink_unregister(void);
185
186#endif /* !_CAN_DEV_H */