USB: add quirk to avoid config and interface strings

Apparently the Configuration and Interface strings aren't used as
often as the Vendor, Product, and Serial strings.  In at least one
device (a Saitek Cyborg Gold 3D joystick), attempts to read the
Configuration string cause the device to stop responding to Control
requests.

This patch (as1226) adds a quirks flag, telling the kernel not to
read a device's Configuration or Interface strings, together with a
new quirk for the offending joystick.

Reported-by: Melchior FRANZ <melchior.franz@gmail.com>
Tested-by: Melchior FRANZ <melchior.franz@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>  [2.6.28 and 2.6.29, nothing earlier]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 49e7f56e0d7f72ea14800a3caf719538897234e3..3922fa915ed20cfd0eeb1171ec2949eedf34e424 100644 (file)
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1719,7 +1719,8 @@ free_interfaces:
        }
        kfree(new_interfaces);
 
-       if (cp->string == NULL)
+       if (cp->string == NULL &&
+                       !(dev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
                cp->string = usb_cache_string(dev, cp->desc.iConfiguration);
 
        /* Now that all the interfaces are set up, register them

diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index c070b34b669de70da98c450eaf7ac4d48e85ec93..ab93918d92076dedec3575b49e5eaacfb2c32e71 100644 (file)
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -54,6 +54,10 @@ static const struct usb_device_id usb_quirk_list[] = {
        { USB_DEVICE(0x0638, 0x0a13), .driver_info =
          USB_QUIRK_STRING_FETCH_255 },
 
+       /* Saitek Cyborg Gold Joystick */
+       { USB_DEVICE(0x06a3, 0x0006), .driver_info =
+                       USB_QUIRK_CONFIG_INTF_STRINGS },
+
        /* M-Systems Flash Disk Pioneers */
        { USB_DEVICE(0x08ec, 0x1000), .driver_info = USB_QUIRK_RESET_RESUME },
 

diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index 4cc2456ef3be17fa88b16ac91bb29f1f9f30422e..c6678919792729b0c0548f6aa15592efc50e1fd1 100644 (file)
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -13,6 +13,7 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/usb.h>
+#include <linux/usb/quirks.h>
 #include "usb.h"
 
 /* Active configuration fields */
@@ -813,7 +814,8 @@ int usb_create_sysfs_intf_files(struct usb_interface *intf)
        if (intf->sysfs_files_created || intf->unregistering)
                return 0;
 
-       if (alt->string == NULL)
+       if (alt->string == NULL &&
+                       !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
                alt->string = usb_cache_string(udev, alt->desc.iInterface);
        if (alt->string)
                retval = device_create_file(&intf->dev, &dev_attr_interface);

diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 7f6c603db654d077f4cd8ee8351c97e8f9957815..2526f3bbd273e522e1ff77b2ba404c87d9a5a56a 100644 (file)
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -16,4 +16,7 @@
 /* device can't handle Set-Interface requests */
 #define USB_QUIRK_NO_SET_INTF          0x00000004
 
+/* device can't handle its Configuration or Interface strings */
+#define USB_QUIRK_CONFIG_INTF_STRINGS  0x00000008
+
 #endif /* __LINUX_USB_QUIRKS_H */