Add support for HW offloading of the netdev trigger. We need to change spinlock to mutex, because if spinlock is used, the trigger_offload() method cannot sleep, which can happen for ethernet PHYs. We can change the spinlock to mutex because, according to Jacek: register_netdevice_notifier() registers raw notifier chain, whose callbacks are not called from atomic context and there are no restrictions on callbacks. See include/linux/notifier.h. Move struct led_trigger_data into global include directory, into file linux/ledtrig.h, so that drivers wanting to offload the trigger can access its settings. Also export the netdev_led_trigger variable and declare it in ledtrih.h so that drivers may check whether the LED is set to this trigger. Signed-off-by: Marek Behún <kabel@xxxxxxxxxx> --- drivers/leds/trigger/ledtrig-netdev.c | 48 ++++++++++----------------- include/linux/ledtrig.h | 40 ++++++++++++++++++++++ 2 files changed, 57 insertions(+), 31 deletions(-) create mode 100644 include/linux/ledtrig.h diff --git a/drivers/leds/trigger/ledtrig-netdev.c b/drivers/leds/trigger/ledtrig-netdev.c index 8f013b6df4fa..d4fa031d3a9e 100644 --- a/drivers/leds/trigger/ledtrig-netdev.c +++ b/drivers/leds/trigger/ledtrig-netdev.c @@ -10,17 +10,16 @@ // Copyright 2005-2006 Openedhand Ltd. // Author: Richard Purdie <rpurdie@xxxxxxxxxxxxxx> -#include <linux/atomic.h> #include <linux/ctype.h> #include <linux/device.h> #include <linux/init.h> #include <linux/jiffies.h> #include <linux/kernel.h> #include <linux/leds.h> +#include <linux/ledtrig.h> #include <linux/list.h> #include <linux/module.h> #include <linux/netdevice.h> -#include <linux/spinlock.h> #include <linux/timer.h> #include "../leds.h" @@ -36,26 +35,6 @@ * */ -struct led_netdev_data { - spinlock_t lock; - - struct delayed_work work; - struct notifier_block notifier; - - struct led_classdev *led_cdev; - struct net_device *net_dev; - - char device_name[IFNAMSIZ]; - atomic_t interval; - unsigned int last_activity; - - unsigned link:1; - unsigned tx:1; - unsigned rx:1; - - unsigned linkup:1; -}; - enum netdev_led_attr { NETDEV_ATTR_LINK, NETDEV_ATTR_TX, @@ -73,6 +52,9 @@ static void set_baseline_state(struct led_netdev_data *trigger_data) if (!led_cdev->blink_brightness) led_cdev->blink_brightness = led_cdev->max_brightness; + if (!led_trigger_offload(led_cdev)) + return; + if (!trigger_data->linkup) led_set_brightness(led_cdev, LED_OFF); else { @@ -96,9 +78,9 @@ static ssize_t device_name_show(struct device *dev, struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); ssize_t len; - spin_lock_bh(&trigger_data->lock); + mutex_lock(&trigger_data->lock); len = sprintf(buf, "%s\n", trigger_data->device_name); - spin_unlock_bh(&trigger_data->lock); + mutex_unlock(&trigger_data->lock); return len; } @@ -114,7 +96,7 @@ static ssize_t device_name_store(struct device *dev, cancel_delayed_work_sync(&trigger_data->work); - spin_lock_bh(&trigger_data->lock); + mutex_lock(&trigger_data->lock); if (trigger_data->net_dev) { dev_put(trigger_data->net_dev); @@ -138,7 +120,7 @@ static ssize_t device_name_store(struct device *dev, trigger_data->last_activity = 0; set_baseline_state(trigger_data); - spin_unlock_bh(&trigger_data->lock); + mutex_unlock(&trigger_data->lock); return size; } @@ -295,6 +277,7 @@ static int netdev_trig_notify(struct notifier_block *nb, netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv); struct led_netdev_data *trigger_data = container_of(nb, struct led_netdev_data, notifier); + bool reset = true; if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER @@ -308,7 +291,7 @@ static int netdev_trig_notify(struct notifier_block *nb, cancel_delayed_work_sync(&trigger_data->work); - spin_lock_bh(&trigger_data->lock); + mutex_lock(&trigger_data->lock); trigger_data->linkup = 0; switch (evt) { @@ -327,12 +310,14 @@ static int netdev_trig_notify(struct notifier_block *nb, case NETDEV_CHANGE: if (netif_carrier_ok(dev)) trigger_data->linkup = 1; + reset = !trigger_data->led_cdev->offloaded; break; } - set_baseline_state(trigger_data); + if (reset) + set_baseline_state(trigger_data); - spin_unlock_bh(&trigger_data->lock); + mutex_unlock(&trigger_data->lock); return NOTIFY_DONE; } @@ -389,7 +374,7 @@ static int netdev_trig_activate(struct led_classdev *led_cdev) if (!trigger_data) return -ENOMEM; - spin_lock_init(&trigger_data->lock); + mutex_init(&trigger_data->lock); trigger_data->notifier.notifier_call = netdev_trig_notify; trigger_data->notifier.priority = 10; @@ -423,12 +408,13 @@ static void netdev_trig_deactivate(struct led_classdev *led_cdev) kfree(trigger_data); } -static struct led_trigger netdev_led_trigger = { +struct led_trigger netdev_led_trigger = { .name = "netdev", .activate = netdev_trig_activate, .deactivate = netdev_trig_deactivate, .groups = netdev_trig_groups, }; +EXPORT_SYMBOL_GPL(netdev_led_trigger); static int __init netdev_trig_init(void) { diff --git a/include/linux/ledtrig.h b/include/linux/ledtrig.h new file mode 100644 index 000000000000..593b2bee6ca0 --- /dev/null +++ b/include/linux/ledtrig.h @@ -0,0 +1,40 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * LED trigger shared structures + */ + +#ifndef __LINUX_LEDTRIG_H__ +#define __LINUX_LEDTRIG_H__ + +#include <linux/atomic.h> +#include <linux/leds.h> +#include <linux/mutex.h> +#include <linux/netdevice.h> + +#if IS_ENABLED(CONFIG_LEDS_TRIGGER_NETDEV) + +struct led_netdev_data { + struct mutex lock; + + struct delayed_work work; + struct notifier_block notifier; + + struct led_classdev *led_cdev; + struct net_device *net_dev; + + char device_name[IFNAMSIZ]; + atomic_t interval; + unsigned int last_activity; + + unsigned link:1; + unsigned tx:1; + unsigned rx:1; + + unsigned linkup:1; +}; + +extern struct led_trigger netdev_led_trigger; + +#endif /* IS_ENABLED(CONFIG_LEDS_TRIGGER_NETDEV) */ + +#endif /* __LINUX_LEDTRIG_H__ */ -- 2.26.2