diff options
Diffstat (limited to 'drivers/net/can/led.c')
| -rw-r--r-- | drivers/net/can/led.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/drivers/net/can/led.c b/drivers/net/can/led.c new file mode 100644 index 00000000000..f27fca65dc4 --- /dev/null +++ b/drivers/net/can/led.c @@ -0,0 +1,124 @@ +/* + * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com> + * Copyright 2012, Kurt Van Dijck <kurt.van.dijck@eia.be> + * + * 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. + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/netdevice.h> +#include <linux/can/dev.h> + +#include <linux/can/led.h> + +static unsigned long led_delay = 50; +module_param(led_delay, ulong, 0644); +MODULE_PARM_DESC(led_delay, + "blink delay time for activity leds (msecs, default: 50)."); + +/* Trigger a LED event in response to a CAN device event */ +void can_led_event(struct net_device *netdev, enum can_led_event event) +{ + struct can_priv *priv = netdev_priv(netdev); + + switch (event) { + case CAN_LED_EVENT_OPEN: + led_trigger_event(priv->tx_led_trig, LED_FULL); + led_trigger_event(priv->rx_led_trig, LED_FULL); + break; + case CAN_LED_EVENT_STOP: + led_trigger_event(priv->tx_led_trig, LED_OFF); + led_trigger_event(priv->rx_led_trig, LED_OFF); + break; + case CAN_LED_EVENT_TX: + if (led_delay) + led_trigger_blink_oneshot(priv->tx_led_trig, + &led_delay, &led_delay, 1); + break; + case CAN_LED_EVENT_RX: + if (led_delay) + led_trigger_blink_oneshot(priv->rx_led_trig, + &led_delay, &led_delay, 1); + break; + } +} +EXPORT_SYMBOL_GPL(can_led_event); + +static void can_led_release(struct device *gendev, void *res) +{ + struct can_priv *priv = netdev_priv(to_net_dev(gendev)); + + led_trigger_unregister_simple(priv->tx_led_trig); + led_trigger_unregister_simple(priv->rx_led_trig); +} + +/* Register CAN LED triggers for a CAN device + * + * This is normally called from a driver's probe function + */ +void devm_can_led_init(struct net_device *netdev) +{ + struct can_priv *priv = netdev_priv(netdev); + void *res; + + res = devres_alloc(can_led_release, 0, GFP_KERNEL); + if (!res) { + netdev_err(netdev, "cannot register LED triggers\n"); + return; + } + + snprintf(priv->tx_led_trig_name, sizeof(priv->tx_led_trig_name), + "%s-tx", netdev->name); + snprintf(priv->rx_led_trig_name, sizeof(priv->rx_led_trig_name), + "%s-rx", netdev->name); + + led_trigger_register_simple(priv->tx_led_trig_name, + &priv->tx_led_trig); + led_trigger_register_simple(priv->rx_led_trig_name, + &priv->rx_led_trig); + + devres_add(&netdev->dev, res); +} +EXPORT_SYMBOL_GPL(devm_can_led_init); + +/* NETDEV rename notifier to rename the associated led triggers too */ +static int can_led_notifier(struct notifier_block *nb, unsigned long msg, + void *data) +{ + struct net_device *netdev = data; + struct can_priv *priv = safe_candev_priv(netdev); + char name[CAN_LED_NAME_SZ]; + + if (!priv) + return NOTIFY_DONE; + + if (msg == NETDEV_CHANGENAME) { + snprintf(name, sizeof(name), "%s-tx", netdev->name); + led_trigger_rename_static(name, priv->tx_led_trig); + + snprintf(name, sizeof(name), "%s-rx", netdev->name); + led_trigger_rename_static(name, priv->rx_led_trig); + } + + return NOTIFY_DONE; +} + +/* notifier block for netdevice event */ +static struct notifier_block can_netdev_notifier __read_mostly = { + .notifier_call = can_led_notifier, +}; + +int __init can_led_notifier_init(void) +{ + return register_netdevice_notifier(&can_netdev_notifier); +} + +void __exit can_led_notifier_exit(void) +{ + unregister_netdevice_notifier(&can_netdev_notifier); +} |