For an xhci host's downstream port, Link Validation System (LVS) is a
hardware which acts as device and used to run link layer tests. Most of
the link layer tests only expects link to be in U0. If a host sends a
setup packet, it is NAKed by LVS. However, there are some tests which
ask host to send some control command like Get Descriptor etc.
This patch adds a sysfs node to add a quirk flag to prevent enumeration
of a device, and then to call a driver for this device which can further
add options to generate test case specific traffic.
Without this patch many Lecroy Link Layer tests such as TD.7.02 fail.
Before a lecroy LVS device is connected to the root hub n, do following:
echo 1 > /sys/bus/usb/devices/usbn/avoid_enum_quirk
Now connect LVS device and run Link Layer tests from Lecroy USB
Compliance Suite.
To get back into normal working situation (to connect a general usb device
to root hub n), do following:
echo 0 > /sys/bus/usb/devices/usbn/avoid_enum_quirk
Signed-off-by: Pratyush Anand <pratyush.anand@xxxxxx>
---
Documentation/ABI/testing/sysfs-bus-usb | 10 +++
drivers/usb/core/hub.c | 105 +++++++++++++++++++++++++++++++-
drivers/usb/core/hub.h | 2 +
drivers/usb/core/sysfs.c | 34 +++++++++++
drivers/usb/core/usb.c | 1 -
include/linux/usb/quirks.h | 3 +
6 files changed, 151 insertions(+), 4 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index f093e59..d7f6bfd 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -236,3 +236,13 @@ Description:
This attribute is to expose these information to user space.
The file will read "hotplug", "wired" and "not used" if the
information is available, and "unknown" otherwise.
+
+What: /sys/bus/usb/device/.../avoid_enum_quirk
+Date: March 2014
+Contact: Pratyush Anand <pratyush.anand@xxxxxx>
+Description:
+ Only root hub allows to write. Writing to
+ other device will return error. Writing 1 to this file tells the
+ kernel that device connected to this root hub must not
+ be enumerated. Ports of this root hub will be used to
+ conncet Link Layer Validation System device.
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 5edcfb2..124b5c8 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -27,6 +27,7 @@
#include <linux/freezer.h>
#include <linux/random.h>
#include <linux/pm_qos.h>
+#include <linux/platform_device.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
@@ -4656,6 +4657,98 @@ static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
return connect_change;
}
+static void usb_destroy_lvs_device(struct usb_hub *hub, int port1)
+{
+ struct usb_device *hdev = hub->hdev;
+ struct platform_device *lvstestdev = hub->ports[port1 -1]->lvstestdev;
+ struct usb_device *udev = hub->ports[port1 - 1]->child;
+
+ if (!lvstestdev) {
+ dev_err(&hdev->dev, "No Platform device at port %d\n", port1);
+ return;
+ }
+
+ platform_device_unregister(lvstestdev);
+
+ kfree(udev);
+
+ hub->ports[port1 -1]->child = NULL;
+ hub->ports[port1 -1]->lvstestdev = NULL;
+ dev_info(&hdev->dev, "LVS device destroyed\n");
+}
+
+static int usb_create_lvs_device(struct usb_hub *hub, int port1)
+{
+ struct usb_device *hdev = hub->hdev;
+ struct usb_device *udev;
+ struct platform_device *lvstestdev = hub->ports[port1 -1]->lvstestdev;
+ int ret;
+
+ if (lvstestdev) {
+ dev_err(&hdev->dev,
+ "Already a platform device at port %d\n", port1);
+ usb_destroy_lvs_device(hub, port1);
+ }
+
+ udev = usb_alloc_dev(hdev, hdev->bus, port1);
+ if (!udev) {
+ dev_err (&hdev->dev, "couldn't allocate port %d usb_device\n",
+ port1);
+ return -ENOMEM;
+ }
+
+ if (hub_is_superspeed(hdev)) {
+ udev->speed = USB_SPEED_SUPER;
+ udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
+ usb_set_device_state(udev, USB_STATE_DEFAULT);
+ ret = hub_enable_device(udev);
+ if (ret < 0) {
+ dev_err(&hdev->dev, "Failed to enable %d\n", ret);
+ goto free_udev;
+ }
+ } else {
+ dev_err(&hdev->dev, "Host not supported\n");
+ ret = -EINVAL;
+ goto free_udev;
+ }
+
+ lvstestdev = platform_device_alloc("lvstestdev", PLATFORM_DEVID_AUTO);
+ if (!lvstestdev) {
+ dev_err(&hdev->dev, "couldn't allocate lvstestdev device\n");
+ ret = -ENOMEM;
+ goto free_udev;
+ }
+
+ /*
+ * udev will be copied to platform_data and then memory of udev
+ * will be released.
+ */
+ ret = platform_device_add_data(lvstestdev, &udev, sizeof(udev));
+ if (ret) {
+ dev_err(&hdev->dev, "couldn't add udev data\n");
+ goto free_lvstestdev;
+ }
+
+ ret = platform_device_add(lvstestdev);
+ if (ret) {
+ dev_err(&hdev->dev, "failed to register lvstestdev device\n");
+ goto free_lvstestdev;
+ }
+
+ hub->ports[port1 -1]->lvstestdev = lvstestdev;
+ hub->ports[port1 -1]->child = udev;
+
+ dev_info(&hdev->dev, "LVS device created\n");
+ return 0;
+
+free_lvstestdev:
+ platform_device_put(lvstestdev);
+free_udev:
+ kfree(udev);
+
+ return ret;
+}
+
static void hub_events(void)
{
struct list_head *tmp;
@@ -4862,9 +4955,15 @@ static void hub_events(void)
}
}
- if (connect_change)
- hub_port_connect_change(hub, i,
- portstatus, portchange);
+ if (connect_change) {
+ if (!(hdev->quirks & USB_QUIRK_ENUM))
+ hub_port_connect_change(hub, i,
+ portstatus, portchange);
+ else if (portstatus & USB_PORT_STAT_ENABLE)
+ usb_create_lvs_device(hub, i);
+ else
+ usb_destroy_lvs_device(hub, i);
+ }
} /* end for i */
/* deal with hub status changes */
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index f608b39..fa25f62 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -85,6 +85,7 @@ struct usb_hub {
* @portnum: port index num based one
* @power_is_on: port's power state
* @did_runtime_put: port has done pm_runtime_put().
+ * @lvs_data: LVS platform device attached to this port
*/
struct usb_port {
struct usb_device *child;
@@ -94,6 +95,7 @@ struct usb_port {
u8 portnum;
unsigned power_is_on:1;
unsigned did_runtime_put:1;
+ void *lvstestdev;
};
#define to_usb_port(_dev) \
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index aa38db4..0a4a5ab 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -234,6 +234,39 @@ static DEVICE_ATTR(avoid_reset_quirk, S_IRUGO | S_IWUSR,
show_avoid_reset_quirk, set_avoid_reset_quirk);
static ssize_t
+show_avoid_enum_quirk(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct usb_device *udev;
+
+ udev = to_usb_device(dev);
+ return sprintf(buf, "%d\n", !!(udev->quirks & USB_QUIRK_ENUM));
+}
+
+static ssize_t
+set_avoid_enum_quirk(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct usb_device *udev = to_usb_device(dev);
+ int val;
+
+ if (udev->parent)
+ return -EINVAL;
+
+ if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1)
+ return -EINVAL;
+ usb_lock_device(udev);
+ if (val)
+ udev->quirks |= USB_QUIRK_ENUM;
+ else
+ udev->quirks &= ~USB_QUIRK_ENUM;
+ usb_unlock_device(udev);
+ return count;
+}
+
+static DEVICE_ATTR(avoid_enum_quirk, S_IRUGO | S_IWUSR,
+ show_avoid_enum_quirk, set_avoid_enum_quirk);
+
+static ssize_t
show_urbnum(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_device *udev;
@@ -668,6 +701,7 @@ static struct attribute *dev_attrs[] = {
&dev_attr_maxchild.attr,
&dev_attr_quirks.attr,
&dev_attr_avoid_reset_quirk.attr,
+ &dev_attr_avoid_enum_quirk.attr,
&dev_attr_authorized.attr,
&dev_attr_remove.attr,
&dev_attr_removable.attr,
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index b10da72..d708baa 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -345,7 +345,6 @@ static unsigned usb_bus_is_wusb(struct usb_bus *bus)
return hcd->wireless;
}
-
/**
* usb_alloc_dev - usb device constructor (usbcore-internal)
* @parent: hub to which device is connected; null to allocate a root hub
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 52f944d..2a1ac98 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -30,4 +30,7 @@
descriptor */
#define USB_QUIRK_DELAY_INIT 0x00000040
+/* device can't be ennumerated. This is a Lecroy Link Layer Validation System */
+#define USB_QUIRK_ENUM 0x00000080
+
#endif /* __LINUX_USB_QUIRKS_H */
--
1.8.1.2
--
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