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>
This commit is contained in:
Rafał Miłecki 2016-08-24 08:42:10 +02:00
parent 00e8571f2b
commit 8765c10606
2 changed files with 287 additions and 0 deletions

View File

@ -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)

View File

@ -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 */
}