mirror of
https://github.com/hardkernel/linux.git
synced 2026-05-12 23:26:06 +09:00
USB gadget patches from Felipe: "usb: gadget: patches for v3.8 renesas_usbhs implements ->pullup() method, switches over to devm_request_irq(), adds support for DMA Engine and got a few miscelaneous cleanups. The NCM gadget got an endianness fix and the Ethernet gadget a frame size fix. We're finally removing the g_file_storage gadget and sticking to g_mass_storage and the new tcm_usb_gadget gadgets since that was a huge duplicaton of effort anyway. While removing g_file_storage, we also had to fix a bunch of defconfigs which were still pointing to the old gadget. There's a big series getting us closer to being able to introduce our configfs interface. The series converts functions into loadable modules which will, eventually, be registered to the configfs interface. Other than that there's the usual typo fixes and miscelaneous cleanups all over the place."
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.