1/*
  2 * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com>
  3 * Copyright 2012, Kurt Van Dijck <kurt.van.dijck@eia.be>
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License version 2 as
  7 * published by the Free Software Foundation.
  8 */
  9
 10#include <linux/module.h>
 11#include <linux/device.h>
 12#include <linux/kernel.h>
 13#include <linux/slab.h>
 14#include <linux/netdevice.h>
 15#include <linux/can/dev.h>
 16
 17#include <linux/can/led.h>
 18
 19static unsigned long led_delay = 50;
 20module_param(led_delay, ulong, 0644);
 21MODULE_PARM_DESC(led_delay,
 22		"blink delay time for activity leds (msecs, default: 50).");
 23
 24/* Trigger a LED event in response to a CAN device event */
 25void can_led_event(struct net_device *netdev, enum can_led_event event)
 26{
 27	struct can_priv *priv = netdev_priv(netdev);
 28
 29	switch (event) {
 30	case CAN_LED_EVENT_OPEN:
 31		led_trigger_event(priv->tx_led_trig, LED_FULL);
 32		led_trigger_event(priv->rx_led_trig, LED_FULL);
 33		led_trigger_event(priv->rxtx_led_trig, LED_FULL);
 34		break;
 35	case CAN_LED_EVENT_STOP:
 36		led_trigger_event(priv->tx_led_trig, LED_OFF);
 37		led_trigger_event(priv->rx_led_trig, LED_OFF);
 38		led_trigger_event(priv->rxtx_led_trig, LED_OFF);
 39		break;
 40	case CAN_LED_EVENT_TX:
 41		if (led_delay) {
 42			led_trigger_blink_oneshot(priv->tx_led_trig,
 43						  &led_delay, &led_delay, 1);
 44			led_trigger_blink_oneshot(priv->rxtx_led_trig,
 45						  &led_delay, &led_delay, 1);
 46		}
 47		break;
 48	case CAN_LED_EVENT_RX:
 49		if (led_delay) {
 50			led_trigger_blink_oneshot(priv->rx_led_trig,
 51						  &led_delay, &led_delay, 1);
 52			led_trigger_blink_oneshot(priv->rxtx_led_trig,
 53						  &led_delay, &led_delay, 1);
 54		}
 55		break;
 56	}
 57}
 58EXPORT_SYMBOL_GPL(can_led_event);
 59
 60static void can_led_release(struct device *gendev, void *res)
 61{
 62	struct can_priv *priv = netdev_priv(to_net_dev(gendev));
 63
 64	led_trigger_unregister_simple(priv->tx_led_trig);
 65	led_trigger_unregister_simple(priv->rx_led_trig);
 66	led_trigger_unregister_simple(priv->rxtx_led_trig);
 67}
 68
 69/* Register CAN LED triggers for a CAN device
 70 *
 71 * This is normally called from a driver's probe function
 72 */
 73void devm_can_led_init(struct net_device *netdev)
 74{
 75	struct can_priv *priv = netdev_priv(netdev);
 76	void *res;
 77
 78	res = devres_alloc(can_led_release, 0, GFP_KERNEL);
 79	if (!res) {
 80		netdev_err(netdev, "cannot register LED triggers\n");
 81		return;
 82	}
 83
 84	snprintf(priv->tx_led_trig_name, sizeof(priv->tx_led_trig_name),
 85		 "%s-tx", netdev->name);
 86	snprintf(priv->rx_led_trig_name, sizeof(priv->rx_led_trig_name),
 87		 "%s-rx", netdev->name);
 88	snprintf(priv->rxtx_led_trig_name, sizeof(priv->rxtx_led_trig_name),
 89		 "%s-rxtx", netdev->name);
 90
 91	led_trigger_register_simple(priv->tx_led_trig_name,
 92				    &priv->tx_led_trig);
 93	led_trigger_register_simple(priv->rx_led_trig_name,
 94				    &priv->rx_led_trig);
 95	led_trigger_register_simple(priv->rxtx_led_trig_name,
 96				    &priv->rxtx_led_trig);
 97
 98	devres_add(&netdev->dev, res);
 99}
100EXPORT_SYMBOL_GPL(devm_can_led_init);
101
102/* NETDEV rename notifier to rename the associated led triggers too */
103static int can_led_notifier(struct notifier_block *nb, unsigned long msg,
104			    void *ptr)
105{
106	struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
107	struct can_priv *priv = safe_candev_priv(netdev);
108	char name[CAN_LED_NAME_SZ];
109
110	if (!priv)
111		return NOTIFY_DONE;
112
113	if (!priv->tx_led_trig || !priv->rx_led_trig || !priv->rxtx_led_trig)
114		return NOTIFY_DONE;
115
116	if (msg == NETDEV_CHANGENAME) {
117		snprintf(name, sizeof(name), "%s-tx", netdev->name);
118		led_trigger_rename_static(name, priv->tx_led_trig);
119
120		snprintf(name, sizeof(name), "%s-rx", netdev->name);
121		led_trigger_rename_static(name, priv->rx_led_trig);
122
123		snprintf(name, sizeof(name), "%s-rxtx", netdev->name);
124		led_trigger_rename_static(name, priv->rxtx_led_trig);
125	}
126
127	return NOTIFY_DONE;
128}
129
130/* notifier block for netdevice event */
131static struct notifier_block can_netdev_notifier __read_mostly = {
132	.notifier_call = can_led_notifier,
133};
134
135int __init can_led_notifier_init(void)
136{
137	return register_netdevice_notifier(&can_netdev_notifier);
138}
139
140void __exit can_led_notifier_exit(void)
141{
142	unregister_netdevice_notifier(&can_netdev_notifier);
143}