kernel: backport patch for specifying USB ports/devices in DT

This allows referencing USB ports/devices that are always present in a
device. This applies to some internal devices, root hub ports and
internal USB hubs.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

2 files changed, 287 insertions, 0 deletions

diff --git a/target/linux/generic/patches-4.4/082-0001-USB-core-let-USB-device-know-device-node.patch b/target/linux/generic/patches-4.4/082-0001-USB-core-let-USB-device-know-device-node.patch
new file mode 100644
index 0000000..901cdf7
--- /dev/null
+++ b/target/linux/generic/patches-4.4/082-0001-USB-core-let-USB-device-know-device-node.patch
@@ -0,0 +1,179 @@
+From 69bec725985324e79b1c47ea287815ac4ddb0521 Mon Sep 17 00:00:00 2001
+From: Peter Chen <peter.chen@freescale.com>
+Date: Fri, 19 Feb 2016 17:26:15 +0800
+Subject: [PATCH] USB: core: let USB device know device node
+
+Although most of USB devices are hot-plug's, there are still some devices
+are hard wired on the board, eg, for HSIC and SSIC interface USB devices.
+If these kinds of USB devices are multiple functions, and they can supply
+other interfaces like i2c, gpios for other devices, we may need to
+describe these at device tree.
+
+In this commit, it uses "reg" in dts as physical port number to match
+the phyiscal port number decided by USB core, if they are the same,
+then the device node is for the device we are creating for USB core.
+
+Signed-off-by: Peter Chen <peter.chen@freescale.com>
+Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
+Acked-by: Alan Stern <stern@rowland.harvard.edu>
+Acked-by: Rob Herring <robh@kernel.org>
+Acked-by: Arnd Bergmann <arnd@arndb.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ .../devicetree/bindings/usb/usb-device.txt         | 28 +++++++++++++
+ drivers/usb/core/Makefile                          |  2 +-
+ drivers/usb/core/of.c                              | 47 ++++++++++++++++++++++
+ drivers/usb/core/usb.c                             | 10 +++++
+ include/linux/usb/of.h                             |  7 ++++
+ 5 files changed, 93 insertions(+), 1 deletion(-)
+ create mode 100644 Documentation/devicetree/bindings/usb/usb-device.txt
+ create mode 100644 drivers/usb/core/of.c
+
+--- /dev/null
++++ b/Documentation/devicetree/bindings/usb/usb-device.txt
+@@ -0,0 +1,28 @@
++Generic USB Device Properties
++
++Usually, we only use device tree for hard wired USB device.
++The reference binding doc is from:
++http://www.firmware.org/1275/bindings/usb/usb-1_0.ps
++
++Required properties:
++- compatible: usbVID,PID. The textual representation of VID, PID shall
++  be in lower case hexadecimal with leading zeroes suppressed. The
++  other compatible strings from the above standard binding could also
++  be used, but a device adhering to this binding may leave out all except
++  for usbVID,PID.
++- reg: the port number which this device is connecting to, the range
++  is 1-31.
++
++Example:
++
++&usb1 {
++	status = "okay";
++
++	#address-cells = <1>;
++	#size-cells = <0>;
++
++	hub: genesys@1 {
++		compatible = "usb5e3,608";
++		reg = <1>;
++	};
++}
+--- a/drivers/usb/core/Makefile
++++ b/drivers/usb/core/Makefile
+@@ -5,7 +5,7 @@
+ usbcore-y := usb.o hub.o hcd.o urb.o message.o driver.o
+ usbcore-y += config.o file.o buffer.o sysfs.o endpoint.o
+ usbcore-y += devio.o notify.o generic.o quirks.o devices.o
+-usbcore-y += port.o
++usbcore-y += port.o of.o
+ 
+ usbcore-$(CONFIG_PCI)		+= hcd-pci.o
+ usbcore-$(CONFIG_ACPI)		+= usb-acpi.o
+--- /dev/null
++++ b/drivers/usb/core/of.c
+@@ -0,0 +1,47 @@
++/*
++ * of.c		The helpers for hcd device tree support
++ *
++ * Copyright (C) 2016 Freescale Semiconductor, Inc.
++ * Author: Peter Chen <peter.chen@freescale.com>
++ *
++ * This program is free software: you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2  of
++ * the License as published by the Free Software Foundation.
++ *
++ * 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.
++ *
++ * You should have received a copy of the GNU General Public License
++ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
++ */
++
++#include <linux/of.h>
++
++/**
++ * usb_of_get_child_node - Find the device node match port number
++ * @parent: the parent device node
++ * @portnum: the port number which device is connecting
++ *
++ * Find the node from device tree according to its port number.
++ *
++ * Return: On success, a pointer to the device node, %NULL on failure.
++ */
++struct device_node *usb_of_get_child_node(struct device_node *parent,
++					int portnum)
++{
++	struct device_node *node;
++	u32 port;
++
++	for_each_child_of_node(parent, node) {
++		if (!of_property_read_u32(node, "reg", &port)) {
++			if (port == portnum)
++				return node;
++		}
++	}
++
++	return NULL;
++}
++EXPORT_SYMBOL_GPL(usb_of_get_child_node);
++
+--- a/drivers/usb/core/usb.c
++++ b/drivers/usb/core/usb.c
+@@ -36,6 +36,7 @@
+ #include <linux/mutex.h>
+ #include <linux/workqueue.h>
+ #include <linux/debugfs.h>
++#include <linux/usb/of.h>
+ 
+ #include <asm/io.h>
+ #include <linux/scatterlist.h>
+@@ -469,6 +470,7 @@ struct usb_device *usb_alloc_dev(struct
+ 		dev->route = 0;
+ 
+ 		dev->dev.parent = bus->controller;
++		dev->dev.of_node = bus->controller->of_node;
+ 		dev_set_name(&dev->dev, "usb%d", bus->busnum);
+ 		root_hub = 1;
+ 	} else {
+@@ -493,6 +495,14 @@ struct usb_device *usb_alloc_dev(struct
+ 		dev->dev.parent = &parent->dev;
+ 		dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
+ 
++		if (!parent->parent) {
++			/* device under root hub's port */
++			port1 = usb_hcd_find_raw_port_number(usb_hcd,
++				port1);
++		}
++		dev->dev.of_node = usb_of_get_child_node(parent->dev.of_node,
++				port1);
++
+ 		/* hub driver sets up TT records */
+ 	}
+ 
+--- a/include/linux/usb/of.h
++++ b/include/linux/usb/of.h
+@@ -15,6 +15,8 @@
+ bool of_usb_host_tpl_support(struct device_node *np);
+ int of_usb_update_otg_caps(struct device_node *np,
+ 			struct usb_otg_caps *otg_caps);
++struct device_node *usb_of_get_child_node(struct device_node *parent,
++			int portnum);
+ #else
+ static inline bool of_usb_host_tpl_support(struct device_node *np)
+ {
+@@ -25,6 +27,11 @@ static inline int of_usb_update_otg_caps
+ {
+ 	return 0;
+ }
++static inline struct device_node *usb_of_get_child_node
++		(struct device_node *parent, int portnum)
++{
++	return NULL;
++}
+ #endif
+ 
+ #if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_USB_SUPPORT)
diff --git a/target/linux/generic/patches-4.4/082-0002-usb-core-usb_alloc_dev-fix-setting-of-portnum.patch b/target/linux/generic/patches-4.4/082-0002-usb-core-usb_alloc_dev-fix-setting-of-portnum.patch
new file mode 100644
index 0000000..15cf4ca
--- /dev/null
+++ b/target/linux/generic/patches-4.4/082-0002-usb-core-usb_alloc_dev-fix-setting-of-portnum.patch
@@ -0,0 +1,108 @@
+From 7222c832254a75dcd67d683df75753d4a4e125bb Mon Sep 17 00:00:00 2001
+From: Nicolai Stange <nicstange@gmail.com>
+Date: Thu, 17 Mar 2016 23:53:02 +0100
+Subject: [PATCH] usb/core: usb_alloc_dev(): fix setting of ->portnum
+
+With commit 69bec7259853 ("USB: core: let USB device know device node"),
+the port1 argument of usb_alloc_dev() gets overwritten as follows:
+
+  ... usb_alloc_dev(..., unsigned port1)
+  {
+    ...
+    if (!parent->parent) {
+      port1 = usb_hcd_find_raw_port_number(..., port1);
+    }
+    ...
+  }
+
+Later on, this now overwritten port1 gets assigned to ->portnum:
+
+  dev->portnum = port1;
+
+However, since xhci_find_raw_port_number() isn't idempotent, the
+aforementioned commit causes a number of KASAN splats like the following:
+
+  BUG: KASAN: slab-out-of-bounds in xhci_find_raw_port_number+0x98/0x170
+                                       at addr ffff8801d9311670
+  Read of size 8 by task kworker/2:1/87
+  [...]
+  Workqueue: usb_hub_wq hub_event
+   0000000000000188 000000005814b877 ffff8800cba17588 ffffffff8191447e
+   0000000041b58ab3 ffffffff82a03209 ffffffff819143a2 ffffffff82a252f4
+   ffff8801d93115e0 0000000000000188 ffff8801d9311628 ffff8800cba17588
+  Call Trace:
+   [<ffffffff8191447e>] dump_stack+0xdc/0x15e
+   [<ffffffff819143a2>] ? _atomic_dec_and_lock+0xa2/0xa2
+   [<ffffffff814e2cd1>] ? print_section+0x61/0xb0
+   [<ffffffff814e4939>] print_trailer+0x179/0x2c0
+   [<ffffffff814f0d84>] object_err+0x34/0x40
+   [<ffffffff814f4388>] kasan_report_error+0x2f8/0x8b0
+   [<ffffffff814eb91e>] ? __slab_alloc+0x5e/0x90
+   [<ffffffff812178c0>] ? __lock_is_held+0x90/0x130
+   [<ffffffff814f5091>] kasan_report+0x71/0xa0
+   [<ffffffff814ec082>] ? kmem_cache_alloc_trace+0x212/0x560
+   [<ffffffff81d99468>] ? xhci_find_raw_port_number+0x98/0x170
+   [<ffffffff814f33d4>] __asan_load8+0x64/0x70
+   [<ffffffff81d99468>] xhci_find_raw_port_number+0x98/0x170
+   [<ffffffff81db0105>] xhci_setup_addressable_virt_dev+0x235/0xa10
+   [<ffffffff81d9ea51>] xhci_setup_device+0x3c1/0x1430
+   [<ffffffff8121cddd>] ? trace_hardirqs_on+0xd/0x10
+   [<ffffffff81d9fac0>] ? xhci_setup_device+0x1430/0x1430
+   [<ffffffff81d9fad3>] xhci_address_device+0x13/0x20
+   [<ffffffff81d2081a>] hub_port_init+0x55a/0x1550
+   [<ffffffff81d28705>] hub_event+0xef5/0x24d0
+   [<ffffffff81d27810>] ? hub_port_debounce+0x2f0/0x2f0
+   [<ffffffff8195e1ee>] ? debug_object_deactivate+0x1be/0x270
+   [<ffffffff81210203>] ? print_rt_rq+0x53/0x2d0
+   [<ffffffff8121657d>] ? trace_hardirqs_off+0xd/0x10
+   [<ffffffff8226acfb>] ? _raw_spin_unlock_irqrestore+0x5b/0x60
+   [<ffffffff81250000>] ? irq_domain_set_hwirq_and_chip+0x30/0xb0
+   [<ffffffff81256339>] ? debug_lockdep_rcu_enabled+0x39/0x40
+   [<ffffffff812178c0>] ? __lock_is_held+0x90/0x130
+   [<ffffffff81196877>] process_one_work+0x567/0xec0
+  [...]
+
+Afterwards, xhci reports some functional errors:
+
+  xhci_hcd 0000:00:14.0: ERROR: unexpected setup address command completion
+                                code 0x11.
+  xhci_hcd 0000:00:14.0: ERROR: unexpected setup address command completion
+                                code 0x11.
+  usb 4-3: device not accepting address 2, error -22
+
+Fix this by not overwriting the port1 argument in usb_alloc_dev(), but
+storing the raw port number as required by OF in an additional variable,
+raw_port.
+
+Fixes: 69bec7259853 ("USB: core: let USB device know device node")
+Signed-off-by: Nicolai Stange <nicstange@gmail.com>
+Acked-by: Alan Stern <stern@rowland.harvard.edu>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/usb/core/usb.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+--- a/drivers/usb/core/usb.c
++++ b/drivers/usb/core/usb.c
+@@ -423,6 +423,7 @@ struct usb_device *usb_alloc_dev(struct
+ 	struct usb_device *dev;
+ 	struct usb_hcd *usb_hcd = bus_to_hcd(bus);
+ 	unsigned root_hub = 0;
++	unsigned raw_port = port1;
+ 
+ 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ 	if (!dev)
+@@ -497,11 +498,11 @@ struct usb_device *usb_alloc_dev(struct
+ 
+ 		if (!parent->parent) {
+ 			/* device under root hub's port */
+-			port1 = usb_hcd_find_raw_port_number(usb_hcd,
++			raw_port = usb_hcd_find_raw_port_number(usb_hcd,
+ 				port1);
+ 		}
+ 		dev->dev.of_node = usb_of_get_child_node(parent->dev.of_node,
+-				port1);
++				raw_port);
+ 
+ 		/* hub driver sets up TT records */
+ 	}