[source] kernel: backport usbport LED trigger driver support for DT

[LEDE Commits]

rmilecki pushed a commit to source.git, branch lede-17.01:
https://git.lede-project.org/dc8392f6a1ca1ec50306af390576d4a19e9a9290

commit dc8392f6a1ca1ec50306af390576d4a19e9a9290
Author: Rafał Miłecki <rafal at milecki.pl>
AuthorDate: Wed Jun 28 11:31:14 2017 +0200

    kernel: backport usbport LED trigger driver support for DT
    
    Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
---
 ...ad-USB-ports-from-DT-in-the-usbport-LED-t.patch | 106 +++++++++++++++++++++
 1 file changed, 106 insertions(+)

diff --git a/target/linux/generic/patches-4.4/084-0003-usb-core-read-USB-ports-from-DT-in-the-usbport-LED-t.patch b/target/linux/generic/patches-4.4/084-0003-usb-core-read-USB-ports-from-DT-in-the-usbport-LED-t.patch
new file mode 100644
index 0000000..65d17c8
--- /dev/null
+++ b/target/linux/generic/patches-4.4/084-0003-usb-core-read-USB-ports-from-DT-in-the-usbport-LED-t.patch
@@ -0,0 +1,106 @@
+From 4f04c210d031667e503d6538a72345a36f3b5d71 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal at milecki.pl>
+Date: Thu, 8 Jun 2017 18:08:32 +0200
+Subject: [PATCH] usb: core: read USB ports from DT in the usbport LED trigger
+ driver
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This uses DT info to read relation description of LEDs and USB ports. If
+DT has properly described LEDs, trigger will know when to turn them on.
+
+Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
+Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
+---
+ drivers/usb/core/ledtrig-usbport.c | 56 ++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 56 insertions(+)
+
+--- a/drivers/usb/core/ledtrig-usbport.c
++++ b/drivers/usb/core/ledtrig-usbport.c
+@@ -11,8 +11,10 @@
+ #include <linux/device.h>
+ #include <linux/leds.h>
+ #include <linux/module.h>
++#include <linux/of.h>
+ #include <linux/slab.h>
+ #include <linux/usb.h>
++#include <linux/usb/of.h>
+ 
+ struct usbport_trig_data {
+ 	struct led_classdev *led_cdev;
+@@ -123,6 +125,57 @@ static const struct attribute_group port
+  * Adding & removing ports
+  ***************************************/
+ 
++/**
++ * usbport_trig_port_observed - Check if port should be observed
++ */
++static bool usbport_trig_port_observed(struct usbport_trig_data *usbport_data,
++				       struct usb_device *usb_dev, int port1)
++{
++	struct device *dev = usbport_data->led_cdev->dev;
++	struct device_node *led_np = dev->of_node;
++	struct of_phandle_args args;
++	struct device_node *port_np;
++	int count, i;
++
++	if (!led_np)
++		return false;
++
++	/* Get node of port being added */
++	port_np = usb_of_get_child_node(usb_dev->dev.of_node, port1);
++	if (!port_np)
++		return false;
++
++	/* Amount of trigger sources for this LED */
++	count = of_count_phandle_with_args(led_np, "trigger-sources",
++					   "#trigger-source-cells");
++	if (count < 0) {
++		dev_warn(dev, "Failed to get trigger sources for %s\n",
++			 led_np->full_name);
++		return false;
++	}
++
++	/* Check list of sources for this specific port */
++	for (i = 0; i < count; i++) {
++		int err;
++
++		err = of_parse_phandle_with_args(led_np, "trigger-sources",
++						 "#trigger-source-cells", i,
++						 &args);
++		if (err) {
++			dev_err(dev, "Failed to get trigger source phandle at index %d: %d\n",
++				i, err);
++			continue;
++		}
++
++		of_node_put(args.np);
++
++		if (args.np == port_np)
++			return true;
++	}
++
++	return false;
++}
++
+ static int usbport_trig_add_port(struct usbport_trig_data *usbport_data,
+ 				 struct usb_device *usb_dev,
+ 				 const char *hub_name, int portnum)
+@@ -141,6 +194,8 @@ static int usbport_trig_add_port(struct
+ 	port->data = usbport_data;
+ 	port->hub = usb_dev;
+ 	port->portnum = portnum;
++	port->observed = usbport_trig_port_observed(usbport_data, usb_dev,
++						    portnum);
+ 
+ 	len = strlen(hub_name) + 8;
+ 	port->port_name = kzalloc(len, GFP_KERNEL);
+@@ -255,6 +310,7 @@ static void usbport_trig_activate(struct
+ 	if (err)
+ 		goto err_free;
+ 	usb_for_each_dev(usbport_data, usbport_trig_add_usb_dev_ports);
++	usbport_trig_update_count(usbport_data);
+ 
+ 	/* Notifications */
+ 	usbport_data->nb.notifier_call = usbport_trig_notify,