kernel-ark/drivers/net/can/led.c
Oliver Hartkopp 45fb4f8d81 can: only rename enabled led triggers when changing the netdev name
Commit a1ef7bd9fc ("can: rename LED trigger name on netdev renames") renames
the led trigger names according to the changed netdevice name.

As not every CAN driver supports and initializes the led triggers, checking for
the CAN private datastructure with safe_candev_priv() in the notifier chain is
not enough.

This patch adds a check when CONFIG_CAN_LEDS is enabled and the driver does not
support led triggers.

For stable 3.9+

Cc: Fabio Baltieri <fabio.baltieri@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2014-05-27 15:05:41 +02:00

128 lines
3.4 KiB
C

/*
* 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 *ptr)
{
struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
struct can_priv *priv = safe_candev_priv(netdev);
char name[CAN_LED_NAME_SZ];
if (!priv)
return NOTIFY_DONE;
if (!priv->tx_led_trig || !priv->rx_led_trig)
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);
}