dev.h

  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/ethtool.h>
 24#include <linux/netdevice.h>
 25
 26/*
 27 * CAN mode
 28 */
 29enum can_mode {
 30	CAN_MODE_STOP = 0,
 31	CAN_MODE_START,
 32	CAN_MODE_SLEEP
 33};
 34
 35enum 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 */
 44struct can_priv {
 45	struct net_device *dev;
 46	struct can_device_stats can_stats;
 47
 48	const struct can_bittiming_const *bittiming_const;
 49	struct can_bittiming bittiming;
 50	struct data_bittiming_params fd, xl;
 51	unsigned int bitrate_const_cnt;
 52	const u32 *bitrate_const;
 53	u32 bitrate_max;
 54	struct can_clock clock;
 55
 56	unsigned int termination_const_cnt;
 57	const u16 *termination_const;
 58	u16 termination;
 59	struct gpio_desc *termination_gpio;
 60	u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX];
 61
 62	unsigned int echo_skb_max;
 63	struct sk_buff **echo_skb;
 64
 65	enum can_state state;
 66
 67	/* CAN controller features - see include/uapi/linux/can/netlink.h */
 68	u32 ctrlmode;		/* current options setting */
 69	u32 ctrlmode_supported;	/* options that can be modified by netlink */
 70
 71	int restart_ms;
 72	struct delayed_work restart_work;
 73
 74	int (*do_set_bittiming)(struct net_device *dev);
 75	int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
 76	int (*do_set_termination)(struct net_device *dev, u16 term);
 77	int (*do_get_state)(const struct net_device *dev,
 78			    enum can_state *state);
 79	int (*do_get_berr_counter)(const struct net_device *dev,
 80				   struct can_berr_counter *bec);
 81};
 82
 83static inline bool can_fd_tdc_is_enabled(const struct can_priv *priv)
 84{
 85	return !!(priv->ctrlmode & CAN_CTRLMODE_FD_TDC_MASK);
 86}
 87
 88static inline bool can_xl_tdc_is_enabled(const struct can_priv *priv)
 89{
 90	return !!(priv->ctrlmode & CAN_CTRLMODE_XL_TDC_MASK);
 91}
 92
 93static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
 94{
 95	return priv->ctrlmode & ~priv->ctrlmode_supported;
 96}
 97
 98static inline bool can_is_canxl_dev_mtu(unsigned int mtu)
 99{
100	return (mtu >= CANXL_MIN_MTU && mtu <= CANXL_MAX_MTU);
101}
102
103void can_setup(struct net_device *dev);
104
105struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
106				    unsigned int txqs, unsigned int rxqs);
107#define alloc_candev(sizeof_priv, echo_skb_max) \
108	alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1)
109#define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \
110	alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count)
111void free_candev(struct net_device *dev);
112
113/* a candev safe wrapper around netdev_priv */
114struct can_priv *safe_candev_priv(struct net_device *dev);
115
116int open_candev(struct net_device *dev);
117void close_candev(struct net_device *dev);
118void can_set_default_mtu(struct net_device *dev);
119void can_set_cap_info(struct net_device *dev);
120int __must_check can_set_static_ctrlmode(struct net_device *dev,
121					 u32 static_mode);
122int can_hwtstamp_get(struct net_device *netdev,
123		     struct kernel_hwtstamp_config *cfg);
124int can_hwtstamp_set(struct net_device *netdev,
125		     struct kernel_hwtstamp_config *cfg,
126		     struct netlink_ext_ack *extack);
127int can_ethtool_op_get_ts_info_hwts(struct net_device *dev,
128				    struct kernel_ethtool_ts_info *info);
129
130int register_candev(struct net_device *dev);
131void unregister_candev(struct net_device *dev);
132
133int can_restart_now(struct net_device *dev);
134void can_bus_off(struct net_device *dev);
135
136const char *can_get_state_str(const enum can_state state);
137const char *can_get_ctrlmode_str(u32 ctrlmode);
138
139static inline bool can_dev_in_xl_only_mode(struct can_priv *priv)
140{
141	const u32 mixed_mode = CAN_CTRLMODE_FD | CAN_CTRLMODE_XL;
142
143	/* When CAN XL is enabled but FD is disabled we are running in
144	 * the so-called 'CANXL-only mode' where the error signalling is
145	 * disabled. This helper function determines the required value
146	 * to disable error signalling in the CAN XL controller.
147	 * The so-called CC/FD/XL 'mixed mode' requires error signalling.
148	 */
149	return ((priv->ctrlmode & mixed_mode) == CAN_CTRLMODE_XL);
150}
151
152/* drop skb if it does not contain a valid CAN frame for sending */
153static inline bool can_dev_dropped_skb(struct net_device *dev, struct sk_buff *skb)
154{
155	struct can_priv *priv = netdev_priv(dev);
156	u32 silent_mode = priv->ctrlmode & (CAN_CTRLMODE_LISTENONLY |
157					    CAN_CTRLMODE_RESTRICTED);
158
159	if (silent_mode) {
160		netdev_info_once(dev, "interface in %s mode, dropping skb\n",
161				 can_get_ctrlmode_str(silent_mode));
162		goto invalid_skb;
163	}
164
165	if (!(priv->ctrlmode & CAN_CTRLMODE_FD) && can_is_canfd_skb(skb)) {
166		netdev_info_once(dev, "CAN FD is disabled, dropping skb\n");
167		goto invalid_skb;
168	}
169
170	if (can_dev_in_xl_only_mode(priv) && !can_is_canxl_skb(skb)) {
171		netdev_info_once(dev,
172				 "Error signaling is disabled, dropping skb\n");
173		goto invalid_skb;
174	}
175
176	return can_dropped_invalid_skb(dev, skb);
177
178invalid_skb:
179	kfree_skb(skb);
180	dev->stats.tx_dropped++;
181	return true;
182}
183
184void can_state_get_by_berr_counter(const struct net_device *dev,
185				   const struct can_berr_counter *bec,
186				   enum can_state *tx_state,
187				   enum can_state *rx_state);
188void can_change_state(struct net_device *dev, struct can_frame *cf,
189		      enum can_state tx_state, enum can_state rx_state);
190
191#ifdef CONFIG_OF
192void of_can_transceiver(struct net_device *dev);
193#else
194static inline void of_can_transceiver(struct net_device *dev) { }
195#endif
196
197extern struct rtnl_link_ops can_link_ops;
198int can_netlink_register(void);
199void can_netlink_unregister(void);
200
201#endif /* !_CAN_DEV_H */