3416eaa1f8
cypress_m8: Packet format is separate from characteristic size The Cypress app note states that when using an 8 byte packet buffer size that the packet format is modified (to be more compact). However I have since discovered that newer DeLorme Earthmate LT-20 devices (those that are low speed USB with 8 byte packet size) STILL use the format that is really supposed to correspond to 32 byte packets. Further confusing things is the subsequent discovery that there are actually two different types of LT-20 - older LT-20's use 32 byte packets which is probably why this issue wasn't originally encountered. The solution here is to flag the packet format separately from the buffer size. Then at initialization time, identify the correct combination and set it up. This is a critical fix for anyone with a newer LT-20. Older devices and non-Earthmate devices should remain unaffected by this change. (If other devices behave in this, uh, unexpected manner, it's now just a simple 1 line change to fix them as well (change the pkt_fmt member for that device). Default behavior with this patch is still to drive the format as per the app-note; of course for Earthmate devices this is overridden. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
||
---|---|---|
.. | ||
atm | ||
class | ||
core | ||
gadget | ||
host | ||
image | ||
misc | ||
mon | ||
serial | ||
storage | ||
Kconfig | ||
Makefile | ||
README | ||
usb-skeleton.c |
To understand all the Linux-USB framework, you'll use these resources: * This source code. This is necessarily an evolving work, and includes kerneldoc that should help you get a current overview. ("make pdfdocs", and then look at "usb.pdf" for host side and "gadget.pdf" for peripheral side.) Also, Documentation/usb has more information. * The USB 2.0 specification (from www.usb.org), with supplements such as those for USB OTG and the various device classes. The USB specification has a good overview chapter, and USB peripherals conform to the widely known "Chapter 9". * Chip specifications for USB controllers. Examples include host controllers (on PCs, servers, and more); peripheral controllers (in devices with Linux firmware, like printers or cell phones); and hard-wired peripherals like Ethernet adapters. * Specifications for other protocols implemented by USB peripheral functions. Some are vendor-specific; others are vendor-neutral but just standardized outside of the www.usb.org team. Here is a list of what each subdirectory here is, and what is contained in them. core/ - This is for the core USB host code, including the usbfs files and the hub class driver ("khubd"). host/ - This is for USB host controller drivers. This includes UHCI, OHCI, EHCI, and others that might be used with more specialized "embedded" systems. gadget/ - This is for USB peripheral controller drivers and the various gadget drivers which talk to them. Individual USB driver directories. A new driver should be added to the first subdirectory in the list below that it fits into. image/ - This is for still image drivers, like scanners or digital cameras. ../input/ - This is for any driver that uses the input subsystem, like keyboard, mice, touchscreens, tablets, etc. ../media/ - This is for multimedia drivers, like video cameras, radios, and any other drivers that talk to the v4l subsystem. ../net/ - This is for network drivers. serial/ - This is for USB to serial drivers. storage/ - This is for USB mass-storage drivers. class/ - This is for all USB device drivers that do not fit into any of the above categories, and work for a range of USB Class specified devices. misc/ - This is for all USB device drivers that do not fit into any of the above categories.