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Diffstat (limited to 'Documentation/usb/ohci.txt')
| -rw-r--r-- | Documentation/usb/ohci.txt | 32 |
1 files changed, 0 insertions, 32 deletions
diff --git a/Documentation/usb/ohci.txt b/Documentation/usb/ohci.txt deleted file mode 100644 index 99320d9..0000000 --- a/Documentation/usb/ohci.txt +++ /dev/null @@ -1,32 +0,0 @@ -23-Aug-2002 - -The "ohci-hcd" driver is a USB Host Controller Driver (HCD) that is derived -from the "usb-ohci" driver from the 2.4 kernel series. The "usb-ohci" code -was written primarily by Roman Weissgaerber <weissg@vienna.at> but with -contributions from many others (read its copyright/licencing header). - -It supports the "Open Host Controller Interface" (OHCI), which standardizes -hardware register protocols used to talk to USB 1.1 host controllers. As -compared to the earlier "Universal Host Controller Interface" (UHCI) from -Intel, it pushes more intelligence into the hardware. USB 1.1 controllers -from vendors other than Intel and VIA generally use OHCI. - -Changes since the 2.4 kernel include - - - improved robustness; bugfixes; and less overhead - - supports the updated and simplified usbcore APIs - - interrupt transfers can be larger, and can be queued - - less code, by using the upper level "hcd" framework - - supports some non-PCI implementations of OHCI - - ... more - -The "ohci-hcd" driver handles all USB 1.1 transfer types. Transfers of all -types can be queued. That was also true in "usb-ohci", except for interrupt -transfers. Previously, using periods of one frame would risk data loss due -to overhead in IRQ processing. When interrupt transfers are queued, those -risks can be minimized by making sure the hardware always has transfers to -work on while the OS is getting around to the relevant IRQ processing. - -- David Brownell - <dbrownell@users.sourceforge.net> - |