net: phy: leds: add support for led triggers on phy link state change

Create an option CONFIG_LED_TRIGGER_PHY (default n), which will create a
set of led triggers for each instantiated PHY device. There is one LED
trigger per link-speed, per-phy.
The triggers are registered during phy_attach and unregistered during
phy_detach.

This allows for a user to configure their system to allow a set of LEDs
not controlled by the phy to represent link state changes on the phy.
LEDS controlled by the phy are unaffected.

For example, we have a board where some of the leds in the
RJ45 socket are controlled by the phy, but others are not. Using the
triggers provided by this patch the leds not controlled by the phy can
be configured to show the current speed of the ethernet connection. The
leds controlled by the phy are unaffected.

Signed-off-by: Josh Cartwright <josh.cartwright@ni.com>
Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
Signed-off-by: Zach Brown <zach.brown@ni.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 51 insertions, 0 deletions

diff --git a/include/linux/phy_led_triggers.h b/include/linux/phy_led_triggers.h
new file mode 100644
index 000000000000..a2daea0a37d2
--- /dev/null
+++ b/include/linux/phy_led_triggers.h
@@ -0,0 +1,51 @@
+/* Copyright (C) 2016 National Instruments Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#ifndef __PHY_LED_TRIGGERS
+#define __PHY_LED_TRIGGERS
+
+struct phy_device;
+
+#ifdef CONFIG_LED_TRIGGER_PHY
+
+#include <linux/leds.h>
+
+#define PHY_LED_TRIGGER_SPEED_SUFFIX_SIZE	10
+#define PHY_MII_BUS_ID_SIZE	(20 - 3)
+
+#define PHY_LINK_LED_TRIGGER_NAME_SIZE (PHY_MII_BUS_ID_SIZE + \
+				       FIELD_SIZEOF(struct mdio_device, addr)+\
+				       PHY_LED_TRIGGER_SPEED_SUFFIX_SIZE)
+
+struct phy_led_trigger {
+	struct led_trigger trigger;
+	char name[PHY_LINK_LED_TRIGGER_NAME_SIZE];
+	unsigned int speed;
+};
+
+
+extern int phy_led_triggers_register(struct phy_device *phy);
+extern void phy_led_triggers_unregister(struct phy_device *phy);
+extern void phy_led_trigger_change_speed(struct phy_device *phy);
+
+#else
+
+static inline int phy_led_triggers_register(struct phy_device *phy)
+{
+	return 0;
+}
+static inline void phy_led_triggers_unregister(struct phy_device *phy) { }
+static inline void phy_led_trigger_change_speed(struct phy_device *phy) { }
+
+#endif
+
+#endif