* Added simplified possibility to schedule UHCI transfers from within KDL.

* Added debugger commands to resolve usb_ids to pipes.
* Adjusted the physical memory allocator to be usable in a slimmed down mode
  when running inside the kernel debugger.
* Implemented USB keyboard support for KDL through a kernel debugger add-on.
* Added kgetc() and made use of it where previously individual methods were used
  to ensure that reading characters always goes through the kernel debugger
  add-ons and the other methods.

This has some preconditions to meet though:
1) The keyboard must be in the boot protocol (currently the case but needs to
   be revisited once we have a full usb_hid).
2) The keyboard must be attached to a UHCI root port (i.e. not use EHCI or OHCI,
   also not through hubs unless those are USB 1.1).
3) the usb_hid driver has to be opened for this to work. This means that for the
   time between initializing USB and when usb_hid is opened by the input_server
   there is no keyboard support.

Also note that this has no way of detecting hot-plug, meaning that you can't
re-attach your USB keyboard from the hub to the root port once in KDL.

On the bright side of things, since this is a non-destructive mechanism it is
possible to enter and leave KDL without loosing the USB state.

Tested OK in QEMU, not tested on real hardware yet, will see in a few minutes.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29291 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/debug.h

@@ -115,6 +115,7 @@ extern void		debug_set_page_fault_info(addr_t faultAddress, addr_t pc,
 extern debug_page_fault_info* debug_get_page_fault_info();
 extern void debug_trap_cpu_in_kdl(bool returnIfHandedOver);
 
+extern char		kgetc(void);
 extern void		kputs(const char *string);
 extern void		kputs_unfiltered(const char *string);
 extern void		kprintf_unfiltered(const char *format, ...)