xref: /openbmc/linux/include/linux/can/dev.h (revision f94909ce)
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/led.h>
21 #include <linux/can/length.h>
22 #include <linux/can/netlink.h>
23 #include <linux/can/skb.h>
24 #include <linux/netdevice.h>
25 
26 /*
27  * CAN mode
28  */
29 enum can_mode {
30 	CAN_MODE_STOP = 0,
31 	CAN_MODE_START,
32 	CAN_MODE_SLEEP
33 };
34 
35 enum can_termination_gpio {
36 	CAN_TERMINATION_GPIO_DISABLED = 0,
37 	CAN_TERMINATION_GPIO_ENABLED,
38 	CAN_TERMINATION_GPIO_MAX,
39 };
40 
41 /*
42  * CAN common private data
43  */
44 struct can_priv {
45 	struct net_device *dev;
46 	struct can_device_stats can_stats;
47 
48 	const struct can_bittiming_const *bittiming_const,
49 		*data_bittiming_const;
50 	struct can_bittiming bittiming, data_bittiming;
51 	const struct can_tdc_const *tdc_const;
52 	struct can_tdc tdc;
53 
54 	unsigned int bitrate_const_cnt;
55 	const u32 *bitrate_const;
56 	const u32 *data_bitrate_const;
57 	unsigned int data_bitrate_const_cnt;
58 	u32 bitrate_max;
59 	struct can_clock clock;
60 
61 	unsigned int termination_const_cnt;
62 	const u16 *termination_const;
63 	u16 termination;
64 	struct gpio_desc *termination_gpio;
65 	u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX];
66 
67 	enum can_state state;
68 
69 	/* CAN controller features - see include/uapi/linux/can/netlink.h */
70 	u32 ctrlmode;		/* current options setting */
71 	u32 ctrlmode_supported;	/* options that can be modified by netlink */
72 	u32 ctrlmode_static;	/* static enabled options for driver/hardware */
73 
74 	int restart_ms;
75 	struct delayed_work restart_work;
76 
77 	int (*do_set_bittiming)(struct net_device *dev);
78 	int (*do_set_data_bittiming)(struct net_device *dev);
79 	int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
80 	int (*do_set_termination)(struct net_device *dev, u16 term);
81 	int (*do_get_state)(const struct net_device *dev,
82 			    enum can_state *state);
83 	int (*do_get_berr_counter)(const struct net_device *dev,
84 				   struct can_berr_counter *bec);
85 	int (*do_get_auto_tdcv)(const struct net_device *dev, u32 *tdcv);
86 
87 	unsigned int echo_skb_max;
88 	struct sk_buff **echo_skb;
89 
90 #ifdef CONFIG_CAN_LEDS
91 	struct led_trigger *tx_led_trig;
92 	char tx_led_trig_name[CAN_LED_NAME_SZ];
93 	struct led_trigger *rx_led_trig;
94 	char rx_led_trig_name[CAN_LED_NAME_SZ];
95 	struct led_trigger *rxtx_led_trig;
96 	char rxtx_led_trig_name[CAN_LED_NAME_SZ];
97 #endif
98 };
99 
100 static inline bool can_tdc_is_enabled(const struct can_priv *priv)
101 {
102 	return !!(priv->ctrlmode & CAN_CTRLMODE_TDC_MASK);
103 }
104 
105 /*
106  * can_get_relative_tdco() - TDCO relative to the sample point
107  *
108  * struct can_tdc::tdco represents the absolute offset from TDCV. Some
109  * controllers use instead an offset relative to the Sample Point (SP)
110  * such that:
111  *
112  * SSP = TDCV + absolute TDCO
113  *     = TDCV + SP + relative TDCO
114  *
115  * -+----------- one bit ----------+-- TX pin
116  *  |<--- Sample Point --->|
117  *
118  *                         --+----------- one bit ----------+-- RX pin
119  *  |<-------- TDCV -------->|
120  *                           |<------------------------>| absolute TDCO
121  *                           |<--- Sample Point --->|
122  *                           |                      |<->| relative TDCO
123  *  |<------------- Secondary Sample Point ------------>|
124  */
125 static inline s32 can_get_relative_tdco(const struct can_priv *priv)
126 {
127 	const struct can_bittiming *dbt = &priv->data_bittiming;
128 	s32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg +
129 				  dbt->phase_seg1) * dbt->brp;
130 
131 	return (s32)priv->tdc.tdco - sample_point_in_tc;
132 }
133 
134 /* helper to define static CAN controller features at device creation time */
135 static inline void can_set_static_ctrlmode(struct net_device *dev,
136 					   u32 static_mode)
137 {
138 	struct can_priv *priv = netdev_priv(dev);
139 
140 	/* alloc_candev() succeeded => netdev_priv() is valid at this point */
141 	priv->ctrlmode = static_mode;
142 	priv->ctrlmode_static = static_mode;
143 
144 	/* override MTU which was set by default in can_setup()? */
145 	if (static_mode & CAN_CTRLMODE_FD)
146 		dev->mtu = CANFD_MTU;
147 }
148 
149 void can_setup(struct net_device *dev);
150 
151 struct 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)
157 void free_candev(struct net_device *dev);
158 
159 /* a candev safe wrapper around netdev_priv */
160 struct can_priv *safe_candev_priv(struct net_device *dev);
161 
162 int open_candev(struct net_device *dev);
163 void close_candev(struct net_device *dev);
164 int can_change_mtu(struct net_device *dev, int new_mtu);
165 
166 int register_candev(struct net_device *dev);
167 void unregister_candev(struct net_device *dev);
168 
169 int can_restart_now(struct net_device *dev);
170 void can_bus_off(struct net_device *dev);
171 
172 const char *can_get_state_str(const enum can_state state);
173 void 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
177 void of_can_transceiver(struct net_device *dev);
178 #else
179 static inline void of_can_transceiver(struct net_device *dev) { }
180 #endif
181 
182 extern struct rtnl_link_ops can_link_ops;
183 int can_netlink_register(void);
184 void can_netlink_unregister(void);
185 
186 #endif /* !_CAN_DEV_H */
187