[Spice-devel] [usbredir PATCH 5/6] usbredirhost: claim/release: ignore NOT_SUPPORTED on attach|detach kernel driver

[Xiaofan Chen]

On Thu, May 3, 2012 at 11:04 PM, Uri Lublin <uril at redhat.com> wrote:
> On Windows libusb_(attach|detach)_kernel_driver are not supported.
> A libusb driver is already installed (device was successfully opened).
> In that case just continue as if operation was successful.
> ---
>  usbredirhost/usbredirhost.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/usbredirhost/usbredirhost.c b/usbredirhost/usbredirhost.c
> index 305dd35..3d77ac8 100644
> --- a/usbredirhost/usbredirhost.c
> +++ b/usbredirhost/usbredirhost.c
> @@ -486,7 +486,8 @@ static int usbredirhost_claim(struct usbredirhost *host, int initial_claim)
>         n = host->config->interface[i].altsetting[0].bInterfaceNumber;
>
>         r = libusb_detach_kernel_driver(host->handle, n);
> -        if (r < 0 && r != LIBUSB_ERROR_NOT_FOUND) {
> +        if (r < 0 && r != LIBUSB_ERROR_NOT_FOUND
> +                  && r != LIBUSB_ERROR_NOT_SUPPORTED) {
>             ERROR("could not detach driver from interface %d (configuration %d): %d",
>                   n, host->config->bConfigurationValue, r);
>             return libusb_status_or_error_to_redir_status(host, r);
> @@ -544,6 +545,7 @@ static void usbredirhost_release(struct usbredirhost *host, int attach_drivers)
>         r = libusb_attach_kernel_driver(host->handle, n);
>         if (r < 0 && r != LIBUSB_ERROR_NOT_FOUND /* No driver */
>                   && r != LIBUSB_ERROR_NO_DEVICE /* Device unplugged */
> +                  && r != LIBUSB_ERROR_NOT_SUPPORTED /* Not supported */
>                   && r != LIBUSB_ERROR_BUSY /* driver rebound already */) {
>             ERROR("could not re-attach driver to interface %d (configuration %d): %d",
>                   n, host->config->bConfigurationValue, r);
> --
> 1.7.7.6

To me the above is not the right fix, the right fix is to limit the call
libusb_detach_kernel_driver() to Linux only. Do not use this
call for other systems since all the other OS does not support this
call -- be it Mac OS X, Windows, or BSDs.


-- 
Xiaofan