diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2012-07-28 11:43:52 +0200 |
|---|---|---|
| committer | Hans de Goede <hdegoede@redhat.com> | 2012-08-22 12:44:20 +0200 |
| commit | daa923ac06cbf5bcac6922a9520aa7fc9919134e (patch) | |
| tree | d1ebd01a111ed3f21f57fc4ce53790816c0c538f | |
| parent | 9b1b7e0acd9f41e6df213e9eeb744e970bdc1544 (diff) | |
detach-kernel-driver: return ERROR_NOT_FOUND if usbfs is already bound (v3)
Currently applications for devices which only are accessed from userspace
can use claim / release interface to make sure they don't get in each others
way. The same however does not work for applications which first need to detach
a "native" / in kernel driver, as this detach will not only detach native
drivers but also the usbfs driver, thus stealing the device from another
userspace / libusbx app.
This patch fixes libusb_detach_kernel_driver to only detach "real" kernel
drivers and not the special usbfs driver used for userspace access to
USB devices. If the usbfs driver is found LIBUSB_ERROR_NOT_FOUND will be
returned to indicate no driver was detached.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
| -rw-r--r-- | libusb/core.c | 4 | ||||
| -rw-r--r-- | libusb/os/linux_usbfs.c | 6 |
2 files changed, 10 insertions, 0 deletions
diff --git a/libusb/core.c b/libusb/core.c index 7c2f4d7..4c513f7 100644 --- a/libusb/core.c +++ b/libusb/core.c @@ -1513,6 +1513,10 @@ int API_EXPORTED libusb_kernel_driver_active(libusb_device_handle *dev, * * This functionality is not available on Darwin or Windows. * + * Note that libusb itself also talks to the device through a special kernel + * driver, if this driver is already attached to the device, this call will + * not detach it and return LIBUSB_ERROR_NOT_FOUND. + * * \param dev a device handle * \param interface_number the interface to detach the driver from * \returns 0 on success diff --git a/libusb/os/linux_usbfs.c b/libusb/os/linux_usbfs.c index 839ebde..1407866 100644 --- a/libusb/os/linux_usbfs.c +++ b/libusb/os/linux_usbfs.c @@ -1538,12 +1538,18 @@ static int op_detach_kernel_driver(struct libusb_device_handle *handle, { int fd = _device_handle_priv(handle)->fd; struct usbfs_ioctl command; + struct usbfs_getdriver getdrv; int r; command.ifno = interface; command.ioctl_code = IOCTL_USBFS_DISCONNECT; command.data = NULL; + getdrv.interface = interface; + r = ioctl(fd, IOCTL_USBFS_GETDRIVER, &getdrv); + if (r == 0 && strcmp(getdrv.driver, "usbfs") == 0) + return LIBUSB_ERROR_NOT_FOUND; + r = ioctl(fd, IOCTL_USBFS_IOCTL, &command); if (r) { if (errno == ENODATA) |