diff options
Diffstat (limited to 'include/linux/can/dev.h')
| -rw-r--r-- | include/linux/can/dev.h | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h new file mode 100644 index 000000000..41ff31795 --- /dev/null +++ b/include/linux/can/dev.h @@ -0,0 +1,238 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * linux/can/dev.h + * + * Definitions for the CAN network device driver interface + * + * Copyright (C) 2006 Andrey Volkov <avolkov@varma-el.com> + * Varma Electronics Oy + * + * Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com> + * + */ + +#ifndef _CAN_DEV_H +#define _CAN_DEV_H + +#include <linux/can.h> +#include <linux/can/error.h> +#include <linux/can/led.h> +#include <linux/can/netlink.h> +#include <linux/can/skb.h> +#include <linux/netdevice.h> + +/* + * CAN mode + */ +enum can_mode { + CAN_MODE_STOP = 0, + CAN_MODE_START, + CAN_MODE_SLEEP +}; + +/* + * CAN common private data + */ +struct can_priv { + struct net_device *dev; + struct can_device_stats can_stats; + + struct can_bittiming bittiming, data_bittiming; + const struct can_bittiming_const *bittiming_const, + *data_bittiming_const; + const u16 *termination_const; + unsigned int termination_const_cnt; + u16 termination; + const u32 *bitrate_const; + unsigned int bitrate_const_cnt; + const u32 *data_bitrate_const; + unsigned int data_bitrate_const_cnt; + u32 bitrate_max; + struct can_clock clock; + + enum can_state state; + + /* CAN controller features - see include/uapi/linux/can/netlink.h */ + u32 ctrlmode; /* current options setting */ + u32 ctrlmode_supported; /* options that can be modified by netlink */ + u32 ctrlmode_static; /* static enabled options for driver/hardware */ + + int restart_ms; + struct delayed_work restart_work; + + int (*do_set_bittiming)(struct net_device *dev); + int (*do_set_data_bittiming)(struct net_device *dev); + int (*do_set_mode)(struct net_device *dev, enum can_mode mode); + int (*do_set_termination)(struct net_device *dev, u16 term); + int (*do_get_state)(const struct net_device *dev, + enum can_state *state); + int (*do_get_berr_counter)(const struct net_device *dev, + struct can_berr_counter *bec); + + unsigned int echo_skb_max; + struct sk_buff **echo_skb; + +#ifdef CONFIG_CAN_LEDS + struct led_trigger *tx_led_trig; + char tx_led_trig_name[CAN_LED_NAME_SZ]; + struct led_trigger *rx_led_trig; + char rx_led_trig_name[CAN_LED_NAME_SZ]; + struct led_trigger *rxtx_led_trig; + char rxtx_led_trig_name[CAN_LED_NAME_SZ]; +#endif +}; + +#define CAN_SYNC_SEG 1 + +/* + * can_bit_time() - Duration of one bit + * + * Please refer to ISO 11898-1:2015, section 11.3.1.1 "Bit time" for + * additional information. + * + * Return: the number of time quanta in one bit. + */ +static inline unsigned int can_bit_time(const struct can_bittiming *bt) +{ + return CAN_SYNC_SEG + bt->prop_seg + bt->phase_seg1 + bt->phase_seg2; +} + +/* + * get_can_dlc(value) - helper macro to cast a given data length code (dlc) + * to u8 and ensure the dlc value to be max. 8 bytes. + * + * To be used in the CAN netdriver receive path to ensure conformance with + * ISO 11898-1 Chapter 8.4.2.3 (DLC field) + */ +#define get_can_dlc(i) (min_t(u8, (i), CAN_MAX_DLC)) +#define get_canfd_dlc(i) (min_t(u8, (i), CANFD_MAX_DLC)) + +/* Check for outgoing skbs that have not been created by the CAN subsystem */ +static inline bool can_skb_headroom_valid(struct net_device *dev, + struct sk_buff *skb) +{ + /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */ + if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv))) + return false; + + /* af_packet does not apply CAN skb specific settings */ + if (skb->ip_summed == CHECKSUM_NONE) { + /* init headroom */ + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + + /* perform proper loopback on capable devices */ + if (dev->flags & IFF_ECHO) + skb->pkt_type = PACKET_LOOPBACK; + else + skb->pkt_type = PACKET_HOST; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + } + + return true; +} + +/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ +static inline bool can_dropped_invalid_skb(struct net_device *dev, + struct sk_buff *skb) +{ + const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + + if (skb->protocol == htons(ETH_P_CAN)) { + if (unlikely(skb->len != CAN_MTU || + cfd->len > CAN_MAX_DLEN)) + goto inval_skb; + } else if (skb->protocol == htons(ETH_P_CANFD)) { + if (unlikely(skb->len != CANFD_MTU || + cfd->len > CANFD_MAX_DLEN)) + goto inval_skb; + } else + goto inval_skb; + + if (!can_skb_headroom_valid(dev, skb)) + goto inval_skb; + + return false; + +inval_skb: + kfree_skb(skb); + dev->stats.tx_dropped++; + return true; +} + +static inline bool can_is_canfd_skb(const struct sk_buff *skb) +{ + /* the CAN specific type of skb is identified by its data length */ + return skb->len == CANFD_MTU; +} + +/* helper to define static CAN controller features at device creation time */ +static inline void can_set_static_ctrlmode(struct net_device *dev, + u32 static_mode) +{ + struct can_priv *priv = netdev_priv(dev); + + /* alloc_candev() succeeded => netdev_priv() is valid at this point */ + priv->ctrlmode = static_mode; + priv->ctrlmode_static = static_mode; + + /* override MTU which was set by default in can_setup()? */ + if (static_mode & CAN_CTRLMODE_FD) + dev->mtu = CANFD_MTU; +} + +/* get data length from can_dlc with sanitized can_dlc */ +u8 can_dlc2len(u8 can_dlc); + +/* map the sanitized data length to an appropriate data length code */ +u8 can_len2dlc(u8 len); + +struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, + unsigned int txqs, unsigned int rxqs); +#define alloc_candev(sizeof_priv, echo_skb_max) \ + alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1) +#define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \ + alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count) +void free_candev(struct net_device *dev); + +/* a candev safe wrapper around netdev_priv */ +struct can_priv *safe_candev_priv(struct net_device *dev); + +int open_candev(struct net_device *dev); +void close_candev(struct net_device *dev); +int can_change_mtu(struct net_device *dev, int new_mtu); + +int register_candev(struct net_device *dev); +void unregister_candev(struct net_device *dev); + +int can_restart_now(struct net_device *dev); +void can_bus_off(struct net_device *dev); + +void can_change_state(struct net_device *dev, struct can_frame *cf, + enum can_state tx_state, enum can_state rx_state); + +int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, + unsigned int idx); +struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, + u8 *len_ptr); +unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); +void can_free_echo_skb(struct net_device *dev, unsigned int idx); + +#ifdef CONFIG_OF +void of_can_transceiver(struct net_device *dev); +#else +static inline void of_can_transceiver(struct net_device *dev) { } +#endif + +struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); +struct sk_buff *alloc_canfd_skb(struct net_device *dev, + struct canfd_frame **cfd); +struct sk_buff *alloc_can_err_skb(struct net_device *dev, + struct can_frame **cf); + +#endif /* !_CAN_DEV_H */ |