Nut upsdev - May 2010 - possible code change to drivers/libusb.c

I doesn't fix any problems but I think it is nicer code. :-)
I don't think we want to call usb_detach_kernel_driver_np unless we 
claimed the device.

$ diff -uw libusb.c.bak libusb.c.new
--- libusb.c.bak        2010-05-11 09:35:39.000000000 -0400
+++ libusb.c.new        2010-05-11 09:32:44.000000000 -0400
@@ -206,18 +206,21 @@

                                 upsdebugx(2, "failed to claim USB 
device: %s", usb_strerror());

+                               if (retries-- > 1) {
+                                       continue;
+                               }
+
+                               fatalx(EXIT_FAILURE, "Can't claim USB 
device [%04x:%04x]: %s", curDevice->VendorID, curDevice->ProductID, 
usb_strerror());
+                       }
+
+                       if (retries > 1) {
                                 if (usb_detach_kernel_driver_np(udev, 
0) < 0) {
                                         upsdebugx(2, "failed to detach 
kernel driver from USB device: %s", usb_strerror());
                                 } else {
                                         upsdebugx(2, "detached kernel 
driver from USB device...");
                                 }
-
-                               if (retries-- > 0) {
-                                       continue;
                                 }

-                               fatalx(EXIT_FAILURE, "Can't claim USB 
device [%04x:%04x]: %s", curDevice->VendorID, curDevice->ProductID, 
usb_strerror());
-                       }
  #else
                         if (usb_claim_interface(udev, 0) < 0) {
                                 fatalx(EXIT_FAILURE, "Can't claim USB 
device [%04x:%04x]: %s", curDevice->VendorID, curDevice->ProductID, 
usb_strerror());

On Tue, May 11, 2010 at 10:10 AM, James <bjlockie at lockie.ca>
wrote:
> ?I doesn't fix any problems but I think it is nicer code. :-)
> I don't think we want to call usb_detach_kernel_driver_np unless we
claimed
> the device.
Actually, we want to call usb_detach_kernel_driver_np() if we *can't*
claim the device, because that usually means that the kernel usbhid
driver has claimed it already (and it needs to be detached).

If we still can't claim it after that, then it is usually a permissions
problem.

-- 
- Charles Lepple