Subject: [net-next PATCH v4 1/3] leds: trigger: netdev: add additional specific link speed mode

From: Christian Marangi <[email-masked]>
Date: Sat, 17 Jun 2023 13:53:53 +0200

Add additional modes for specific link speed. Use ethtool APIs to get the
current link speed and enable the LED accordingly. Under netdev event
handler the rtnl lock is already held and is not needed to be set to
access ethtool APIs.

This is especially useful for PHY and Switch that supports LEDs hw
control for specific link speed. (example scenario a PHY that have 2 LED
connected one green and one orange where the green is turned on with
1000mbps speed and orange is turned on with 10mpbs speed)

On mode set from sysfs we check if we have enabled split link speed mode
and reject enabling generic link mode to prevent wrong and redundant
configuration.

Rework logic on the set baseline state to support these new modes to
select if we need to turn on or off the LED.

Add additional modes:
- link_10: Turn on LED when link speed is 10mbps
- link_100: Turn on LED when link speed is 100mbps
- link_1000: Turn on LED when link speed is 1000mbps

Signed-off-by: Christian Marangi <[email-masked]>
Reviewed-by: Andrew Lunn <[email-masked]>
---
 drivers/leds/trigger/ledtrig-netdev.c | 80 +++++++++++++++++++++++----
 include/linux/leds.h                  |  3 +
 2 files changed, 73 insertions(+), 10 deletions(-)

diff --git a/drivers/leds/trigger/ledtrig-netdev.c b/drivers/leds/trigger/ledtrig-netdev.c
index c9b040bacbb0..8e6132f069af 100644
--- a/drivers/leds/trigger/ledtrig-netdev.c
+++ b/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 +54,8 @@ struct led_netdev_data {
 	unsigned int last_activity;
 
 	unsigned long mode;
+	int link_speed;
+
 	bool carrier_link_up;
 	bool hw_control;
 };
@@ -77,7 +81,24 @@ 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 (blink_on)
 			led_set_brightness(led_cdev,
 					   led_cdev->blink_brightness);
 		else
@@ -161,6 +182,18 @@ 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;
+}
+
 static ssize_t device_name_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
@@ -196,8 +229,12 @@ 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;
+	if (trigger_data->net_dev != NULL) {
+		rtnl_lock();
+		get_device_state(trigger_data);
+		rtnl_unlock();
+	}
 
 	trigger_data->last_activity = 0;
 
@@ -234,6 +271,9 @@ 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_TX:
 	case TRIGGER_NETDEV_RX:
 		bit = attr;
@@ -249,7 +289,7 @@ 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 +299,9 @@ 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_TX:
 	case TRIGGER_NETDEV_RX:
 		bit = attr;
@@ -267,13 +310,20 @@ 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 +345,9 @@ 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(tx, TRIGGER_NETDEV_TX);
 DEFINE_NETDEV_TRIGGER(rx, TRIGGER_NETDEV_RX);
 
@@ -338,6 +391,9 @@ static DEVICE_ATTR_RW(interval);
 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_rx.attr,
 	&dev_attr_tx.attr,
 	&dev_attr_interval.attr,
@@ -368,9 +424,10 @@ 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;
 	switch (evt) {
 	case NETDEV_CHANGENAME:
-		trigger_data->carrier_link_up = netif_carrier_ok(dev);
+		get_device_state(trigger_data);
 		fallthrough;
 	case NETDEV_REGISTER:
 		dev_put(trigger_data->net_dev);
@@ -383,7 +440,7 @@ 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;
 	}
 
@@ -426,7 +483,10 @@ 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);
 		interval = jiffies_to_msecs(
 				atomic_read(&trigger_data->interval));
 		/* base state is ON (link present) */
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 4b3d8bda1fff..39f15b1e772c 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -582,6 +582,9 @@ 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_TX,
 	TRIGGER_NETDEV_RX,
 
-- 
2.40.1