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Notes on the the generic USB-OHCI driver
This driver (drivers/usb/usb_ohci.[ch]) is the result of the merge of
various existing OHCI drivers that were basically identical beside
cpu/board dependant initalization. This initalization has been moved
into cpu/board directories and are called via the hooks below.
Configuration options
CONFIG_USB_OHCI_NEW: enable the new OHCI driver
CONFIG_SYS_USB_OHCI_BOARD_INIT: call the board dependant hooks:
- extern int usb_board_init(void);
- extern int usb_board_stop(void);
- extern int usb_cpu_init_fail(void);
CONFIG_SYS_USB_OHCI_CPU_INIT: call the cpu dependant hooks:
- extern int usb_cpu_init(void);
- extern int usb_cpu_stop(void);
- extern int usb_cpu_init_fail(void);
CONFIG_SYS_USB_OHCI_REGS_BASE: defines the base address of the OHCI
CONFIG_SYS_USB_OHCI_MAX_ROOT_PORTS: maximal number of ports of the
root hub.
Endianness issues
The USB bus operates in little endian, but unfortunately there are
OHCI controllers that operate in big endian such as ppc4xx and
mpc5xxx. For these the config option
needs to be defined.
PCI Controllers
You'll need to define
If you have several USB PCI controllers, define
CONFIG_PCI_OHCI_DEVNO: number of the OHCI device in PCI list
If undefined, the first instance found in PCI space will be used.
PCI Controllers need to do byte swapping on register accesses, so they
should to define: