From 996a953de02ffb852c9ac736f4e892008ed68884 Mon Sep 17 00:00:00 2001 From: Fabio Baltieri Date: Tue, 18 Dec 2012 18:50:55 +0100 Subject: can: add tx/rx LED trigger support This patch implements the functions to add two LED triggers, named -tx and -rx, to a canbus device driver. Triggers are called from specific handlers by each CAN device driver and can be disabled altogether with a Kconfig option. The implementation keeps the LED on when the interface is UP and blinks the LED on network activity at a configurable rate. This only supports can-dev based drivers, as it uses some support field in the can_priv structure. Supported drivers should call devm_can_led_init() and can_led_event() as needed. Cleanup is handled automatically by devres, so no *_exit function is needed. Supported events are: - CAN_LED_EVENT_OPEN: turn on tx/rx LEDs - CAN_LED_EVENT_STOP: turn off tx/rx LEDs - CAN_LED_EVENT_TX: trigger tx LED blink - CAN_LED_EVENT_RX: trigger tx LED blink Cc: Wolfgang Grandegger Cc: Marc Kleine-Budde Signed-off-by: Fabio Baltieri Acked-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can/dev.h | 8 ++++++++ include/linux/can/led.h | 42 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+) create mode 100644 include/linux/can/led.h (limited to 'include/linux/can') diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 2b2fc345afca..7747d9bcdc84 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -16,6 +16,7 @@ #include #include #include +#include /* * CAN mode @@ -52,6 +53,13 @@ struct can_priv { 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]; +#endif }; /* diff --git a/include/linux/can/led.h b/include/linux/can/led.h new file mode 100644 index 000000000000..12d5549abb95 --- /dev/null +++ b/include/linux/can/led.h @@ -0,0 +1,42 @@ +/* + * Copyright 2012, Fabio Baltieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef CAN_LED_H +#define CAN_LED_H + +#include +#include + +enum can_led_event { + CAN_LED_EVENT_OPEN, + CAN_LED_EVENT_STOP, + CAN_LED_EVENT_TX, + CAN_LED_EVENT_RX, +}; + +#ifdef CONFIG_CAN_LEDS + +/* keep space for interface name + "-tx"/"-rx" suffix and null terminator */ +#define CAN_LED_NAME_SZ (IFNAMSIZ + 4) + +void can_led_event(struct net_device *netdev, enum can_led_event event); +void devm_can_led_init(struct net_device *netdev); + +#else + +static inline void can_led_event(struct net_device *netdev, + enum can_led_event event) +{ +} +static inline void devm_can_led_init(struct net_device *netdev) +{ +} + +#endif + +#endif -- cgit From bf03a5379cd3492fbeca42111340581ba9dee0b8 Mon Sep 17 00:00:00 2001 From: Kurt Van Dijck Date: Tue, 18 Dec 2012 18:50:56 +0100 Subject: can: export a safe netdev_priv wrapper for candev In net_device notifier calls, it was impossible to determine if a CAN device is based on candev in a safe way. This patch adds such test in order to access candev storage from within those notifiers. Signed-off-by: Kurt Van Dijck Acked-by: Oliver Hartkopp Signed-off-by: Fabio Baltieri Signed-off-by: Marc Kleine-Budde --- include/linux/can/dev.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/can') diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 7747d9bcdc84..fb0ab651a041 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -106,6 +106,9 @@ u8 can_len2dlc(u8 len); struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 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); -- cgit From a1ef7bd9fce8aba8e4701e60208148fb3bc9bdd4 Mon Sep 17 00:00:00 2001 From: Kurt Van Dijck Date: Tue, 18 Dec 2012 18:50:57 +0100 Subject: can: rename LED trigger name on netdev renames The LED trigger name for CAN devices is based on the initial CAN device name, but does never change. The LED trigger name is not guaranteed to be unique in case of hotplugging CAN devices. This patch tries to address this problem by modifying the LED trigger name according to the CAN device name when the latter changes. v1 - Kurt Van Dijck v2 - Fabio Baltieri - remove rename blocking if trigger is bound - use led-subsystem function for the actual rename (still WiP) - call init/exit functions from dev.c v3 - Kurt Van Dijck - safe operation for non-candev based devices (vcan, slcan) based on earlier patch v4 - Kurt Van Dijck - trivial patch mistakes fixed Signed-off-by: Kurt Van Dijck Signed-off-by: Fabio Baltieri Signed-off-by: Marc Kleine-Budde --- include/linux/can/led.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux/can') diff --git a/include/linux/can/led.h b/include/linux/can/led.h index 12d5549abb95..9c1167baf273 100644 --- a/include/linux/can/led.h +++ b/include/linux/can/led.h @@ -26,6 +26,8 @@ enum can_led_event { void can_led_event(struct net_device *netdev, enum can_led_event event); void devm_can_led_init(struct net_device *netdev); +int __init can_led_notifier_init(void); +void __exit can_led_notifier_exit(void); #else @@ -36,6 +38,13 @@ static inline void can_led_event(struct net_device *netdev, static inline void devm_can_led_init(struct net_device *netdev) { } +static inline int can_led_notifier_init(void) +{ + return 0; +} +static inline void can_led_notifier_exit(void) +{ +} #endif -- cgit From 156c2bb9f88065c8da78814f98fde665a5cbb527 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Thu, 17 Jan 2013 18:43:39 +0100 Subject: can: add private data space for CAN sk_buffs The struct can_skb_priv is used to transport additional information along with the stored struct can(fd)_frame that can not be contained in existing struct sk_buff elements. can_skb_priv is located in the skb headroom, which does not touch the existing CAN sk_buff usage with skb->data and skb->len, so that even out-of-tree CAN drivers can be used without changes. Btw. out-of-tree CAN drivers without can_skb_priv in the sk_buff headroom would not support features based on can_skb_priv. The can_skb_priv->ifindex contains the first interface where the CAN frame appeared on the local host. Unfortunately skb->skb_iif can not be used as this value is overwritten in every netif_receive_skb() call. Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can/skb.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 include/linux/can/skb.h (limited to 'include/linux/can') diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h new file mode 100644 index 000000000000..4b0f24d3a878 --- /dev/null +++ b/include/linux/can/skb.h @@ -0,0 +1,35 @@ +/* + * linux/can/skb.h + * + * Definitions for the CAN network socket buffer + * + * Copyright (C) 2012 Oliver Hartkopp + * + */ + +#ifndef CAN_SKB_H +#define CAN_SKB_H + +#include +#include + +/* + * The struct can_skb_priv is used to transport additional information along + * with the stored struct can(fd)_frame that can not be contained in existing + * struct sk_buff elements. + * N.B. that this information must not be modified in cloned CAN sk_buffs. + * To modify the CAN frame content or the struct can_skb_priv content + * skb_copy() needs to be used instead of skb_clone(). + */ + +/** + * struct can_skb_priv - private additional data inside CAN sk_buffs + * @ifindex: ifindex of the first interface the CAN frame appeared on + * @cf: align to the following CAN frame at skb->data + */ +struct can_skb_priv { + int ifindex; + struct can_frame cf[0]; +}; + +#endif /* CAN_SKB_H */ -- cgit From 2bf3440d7b8755f2627232e6a4c37efbbe053685 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Mon, 28 Jan 2013 08:33:33 +0000 Subject: can: rework skb reserved data handling Added accessor and skb_reserve helpers for struct can_skb_priv. Removed pointless skb_headroom() check. Signed-off-by: Oliver Hartkopp CC: Marc Kleine-Budde Signed-off-by: David S. Miller --- include/linux/can/skb.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/linux/can') diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h index 4b0f24d3a878..2f0543f7510c 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -32,4 +32,14 @@ struct can_skb_priv { struct can_frame cf[0]; }; +static inline struct can_skb_priv *can_skb_prv(struct sk_buff *skb) +{ + return (struct can_skb_priv *)(skb->head); +} + +static inline void can_skb_reserve(struct sk_buff *skb) +{ + skb_reserve(skb, sizeof(struct can_skb_priv)); +} + #endif /* CAN_SKB_H */ -- cgit