Merge branch 'leds-trigger-netdev-add-additional-modes'

Christian Marangi says:

====================
leds: trigger: netdev: add additional modes

This is a continue of [1]. It was decided to take a more gradual
approach to implement LEDs support for switch and phy starting with
basic support and then implementing the hw control part when we have all
the prereq done.

This should be the final part for the netdev trigger.
I added net-next tag and added netdev mailing list since I was informed
that this should be merged with netdev branch.

We collect some info around and we found a good set of modes that are
common in almost all the PHY and Switch.

These modes are:
- Modes for dedicated link speed(10, 100, 1000 mbps). Additional mode
  can be added later following this example.
- Modes for half and full duplex.

The original idea was to add hw control only modes.
While the concept makes sense in practice it would results in lots of
additional code and extra check to make sure we are setting correct modes.

With the suggestion from Andrew it was pointed out that using the ethtool
APIs we can actually get the current link speed and duplex and this
effectively removed the problem of having hw control only modes since we
can fallback to software.

Since these modes are supported by software, we can skip providing an
user for this in the LED driver to support hw control for these new modes
(that will come right after this is merged) and prevent this to be another
multi subsystem series.

For link speed and duplex we use ethtool APIs.

To call ethtool APIs, rtnl lock is needed but this can be skipped on
handling netdev events as the lock is already held.

[1] https://lore.kernel.org/lkml/20230216013230.22978-1-ansuelsmth@gmail.com/
====================

Link: https://lore.kernel.org/r/20230619204700.6665-1-ansuelsmth@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/leds/trigger/ledtrig-netdev.c

@@ -13,6 +13,7 @@
 #include <linux/atomic.h>
 #include <linux/ctype.h>
 #include <linux/device.h>
+#include <linux/ethtool.h>
 #include <linux/init.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
@@ -21,6 +22,7 @@
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/mutex.h>
+#include <linux/rtnetlink.h>
 #include <linux/timer.h>
 #include "../leds.h"
 
@@ -52,6 +54,9 @@ struct led_netdev_data {
 	unsigned int last_activity;
 
 	unsigned long mode;
+	int link_speed;
+	u8 duplex;
+
 	bool carrier_link_up;
 	bool hw_control;
 };
@@ -77,7 +82,32 @@ static void set_baseline_state(struct led_netdev_data *trigger_data)
 	if (!trigger_data->carrier_link_up) {
 		led_set_brightness(led_cdev, LED_OFF);
 	} else {
+		bool blink_on = false;
+
 		if (test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode))
+			blink_on = true;
+
+		if (test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) &&
+		    trigger_data->link_speed == SPEED_10)
+			blink_on = true;
+
+		if (test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) &&
+		    trigger_data->link_speed == SPEED_100)
+			blink_on = true;
+
+		if (test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) &&
+		    trigger_data->link_speed == SPEED_1000)
+			blink_on = true;
+
+		if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) &&
+		    trigger_data->duplex == DUPLEX_HALF)
+			blink_on = true;
+
+		if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode) &&
+		    trigger_data->duplex == DUPLEX_FULL)
+			blink_on = true;
+
+		if (blink_on)
 			led_set_brightness(led_cdev,
 					   led_cdev->blink_brightness);
 		else
@@ -161,6 +191,20 @@ static bool can_hw_control(struct led_netdev_data *trigger_data)
 	return true;
 }
 
+static void get_device_state(struct led_netdev_data *trigger_data)
+{
+	struct ethtool_link_ksettings cmd;
+
+	trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev);
+	if (!trigger_data->carrier_link_up)
+		return;
+
+	if (!__ethtool_get_link_ksettings(trigger_data->net_dev, &cmd)) {
+		trigger_data->link_speed = cmd.base.speed;
+		trigger_data->duplex = cmd.base.duplex;
+	}
+}
+
 static ssize_t device_name_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
@@ -196,8 +240,13 @@ static int set_device_name(struct led_netdev_data *trigger_data,
 		    dev_get_by_name(&init_net, trigger_data->device_name);
 
 	trigger_data->carrier_link_up = false;
-	if (trigger_data->net_dev != NULL)
-		trigger_data->carrier_link_up = netif_carrier_ok(trigger_data->net_dev);
+	trigger_data->link_speed = SPEED_UNKNOWN;
+	trigger_data->duplex = DUPLEX_UNKNOWN;
+	if (trigger_data->net_dev != NULL) {
+		rtnl_lock();
+		get_device_state(trigger_data);
+		rtnl_unlock();
+	}
 
 	trigger_data->last_activity = 0;
 
@@ -234,6 +283,11 @@ static ssize_t netdev_led_attr_show(struct device *dev, char *buf,
 
 	switch (attr) {
 	case TRIGGER_NETDEV_LINK:
+	case TRIGGER_NETDEV_LINK_10:
+	case TRIGGER_NETDEV_LINK_100:
+	case TRIGGER_NETDEV_LINK_1000:
+	case TRIGGER_NETDEV_HALF_DUPLEX:
+	case TRIGGER_NETDEV_FULL_DUPLEX:
 	case TRIGGER_NETDEV_TX:
 	case TRIGGER_NETDEV_RX:
 		bit = attr;
@@ -249,7 +303,7 @@ static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
 				     size_t size, enum led_trigger_netdev_modes attr)
 {
 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
-	unsigned long state;
+	unsigned long state, mode = trigger_data->mode;
 	int ret;
 	int bit;
 
@@ -259,6 +313,11 @@ static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
 
 	switch (attr) {
 	case TRIGGER_NETDEV_LINK:
+	case TRIGGER_NETDEV_LINK_10:
+	case TRIGGER_NETDEV_LINK_100:
+	case TRIGGER_NETDEV_LINK_1000:
+	case TRIGGER_NETDEV_HALF_DUPLEX:
+	case TRIGGER_NETDEV_FULL_DUPLEX:
 	case TRIGGER_NETDEV_TX:
 	case TRIGGER_NETDEV_RX:
 		bit = attr;
@@ -267,13 +326,20 @@ static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
 		return -EINVAL;
 	}
 
-	cancel_delayed_work_sync(&trigger_data->work);
-
 	if (state)
-		set_bit(bit, &trigger_data->mode);
+		set_bit(bit, &mode);
 	else
-		clear_bit(bit, &trigger_data->mode);
+		clear_bit(bit, &mode);
+
+	if (test_bit(TRIGGER_NETDEV_LINK, &mode) &&
+	    (test_bit(TRIGGER_NETDEV_LINK_10, &mode) ||
+	     test_bit(TRIGGER_NETDEV_LINK_100, &mode) ||
+	     test_bit(TRIGGER_NETDEV_LINK_1000, &mode)))
+		return -EINVAL;
+
+	cancel_delayed_work_sync(&trigger_data->work);
 
+	trigger_data->mode = mode;
 	trigger_data->hw_control = can_hw_control(trigger_data);
 
 	set_baseline_state(trigger_data);
@@ -295,6 +361,11 @@ static ssize_t netdev_led_attr_store(struct device *dev, const char *buf,
 	static DEVICE_ATTR_RW(trigger_name)
 
 DEFINE_NETDEV_TRIGGER(link, TRIGGER_NETDEV_LINK);
+DEFINE_NETDEV_TRIGGER(link_10, TRIGGER_NETDEV_LINK_10);
+DEFINE_NETDEV_TRIGGER(link_100, TRIGGER_NETDEV_LINK_100);
+DEFINE_NETDEV_TRIGGER(link_1000, TRIGGER_NETDEV_LINK_1000);
+DEFINE_NETDEV_TRIGGER(half_duplex, TRIGGER_NETDEV_HALF_DUPLEX);
+DEFINE_NETDEV_TRIGGER(full_duplex, TRIGGER_NETDEV_FULL_DUPLEX);
 DEFINE_NETDEV_TRIGGER(tx, TRIGGER_NETDEV_TX);
 DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX);
 
@@ -335,12 +406,28 @@ static ssize_t interval_store(struct device *dev,
 
 static DEVICE_ATTR_RW(interval);
 
+static ssize_t hw_control_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", trigger_data->hw_control);
+}
+
+static DEVICE_ATTR_RO(hw_control);
+
 static struct attribute *netdev_trig_attrs[] = {
 	&dev_attr_device_name.attr,
 	&dev_attr_link.attr,
+	&dev_attr_link_10.attr,
+	&dev_attr_link_100.attr,
+	&dev_attr_link_1000.attr,
+	&dev_attr_full_duplex.attr,
+	&dev_attr_half_duplex.attr,
 	&dev_attr_rx.attr,
 	&dev_attr_tx.attr,
 	&dev_attr_interval.attr,
+	&dev_attr_hw_control.attr,
 	NULL
 };
 ATTRIBUTE_GROUPS(netdev_trig);
@@ -368,9 +455,11 @@ static int netdev_trig_notify(struct notifier_block *nb,
 	mutex_lock(&trigger_data->lock);
 
 	trigger_data->carrier_link_up = false;
+	trigger_data->link_speed = SPEED_UNKNOWN;
+	trigger_data->duplex = DUPLEX_UNKNOWN;
 	switch (evt) {
 	case NETDEV_CHANGENAME:
-		trigger_data->carrier_link_up = netif_carrier_ok(dev);
+		get_device_state(trigger_data);
 		fallthrough;
 	case NETDEV_REGISTER:
 		if (trigger_data->net_dev)
@@ -384,7 +473,7 @@ static int netdev_trig_notify(struct notifier_block *nb,
 		break;
 	case NETDEV_UP:
 	case NETDEV_CHANGE:
-		trigger_data->carrier_link_up = netif_carrier_ok(dev);
+		get_device_state(trigger_data);
 		break;
 	}
 
@@ -427,7 +516,12 @@ static void netdev_trig_work(struct work_struct *work)
 	if (trigger_data->last_activity != new_activity) {
 		led_stop_software_blink(trigger_data->led_cdev);
 
-		invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode);
+		invert = test_bit(TRIGGER_NETDEV_LINK, &trigger_data->mode) ||
+			 test_bit(TRIGGER_NETDEV_LINK_10, &trigger_data->mode) ||
+			 test_bit(TRIGGER_NETDEV_LINK_100, &trigger_data->mode) ||
+			 test_bit(TRIGGER_NETDEV_LINK_1000, &trigger_data->mode) ||
+			 test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &trigger_data->mode) ||
+			 test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &trigger_data->mode);
 		interval = jiffies_to_msecs(
 				atomic_read(&trigger_data->interval));
 		/* base state is ON (link present) */

include/linux/leds.h

@@ -555,6 +555,11 @@ static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
 /* Trigger specific enum */
 enum led_trigger_netdev_modes {
 	TRIGGER_NETDEV_LINK = 0,
+	TRIGGER_NETDEV_LINK_10,
+	TRIGGER_NETDEV_LINK_100,
+	TRIGGER_NETDEV_LINK_1000,
+	TRIGGER_NETDEV_HALF_DUPLEX,
+	TRIGGER_NETDEV_FULL_DUPLEX,
 	TRIGGER_NETDEV_TX,
 	TRIGGER_NETDEV_RX,