u-boot/doc/README.generic_usb_ohci
Marcel Ziswiler 7817cb2083 fix comments with new drivers organization
Signed-off-by: Marcel Ziswiler <marcel@ziswiler.com>
2008-01-09 21:48:49 +01:00

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1.4 KiB
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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
CFG_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);
CFG_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);
CFG_USB_OHCI_REGS_BASE: defines the base address of the OHCI
registers
CFG_USB_OHCI_SLOT_NAME: slot name
CFG_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
CFG_OHCI_BE_CONTROLLER
needs to be defined.
PCI Controllers
----------------
You'll need to define
CONFIG_PCI_OHCI
PCI Controllers need to do byte swapping on register accesses, so they
should to define:
CFG_OHCI_SWAP_REG_ACCESS