Implement usb_enable()
Reorder/Modify usb_drv_init() to match closer the OF and remove a freeze
(USB registers were accessed before the USB module was enabled)
Add a panic in USB isr to be sure we notice when it's called
Reset GPIOA direction for usb_detect() to notice extraction
Add some comments
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23184 a1c6a512-1295-4272-9138-f99709370657
Work based on AMD 5536 linux driver and AMD Geode CS5536 datasheet
Rockbox still doesn't reboot on USB insert
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21689 a1c6a512-1295-4272-9138-f99709370657