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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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7a0f0d9512
This patch (as1273) fixes two(!) bugs introduced by the new Clear-TT-Buffer implementation in ehci-hcd. It is now possible for an idle QH to have some URBs on its queue -- this will happen if a Clear-TT-Buffer is pending for the QH's endpoint. Consequently we should not issue a warning when someone tries to unlink an URB from an idle QH; instead we should process the request immediately. The refcounts for QHs could get messed up, because submit_async() would increment the refcount when calling qh_link_async() and qh_link_async() would then refuse to link the QH into the schedule if a Clear-TT-Buffer was pending. Instead we should increment the refcount only when the QH actually is added to the schedule. The current code tries to be clever by leaving the refcount alone if an unlink is immediately followed by a relink; the patch changes this to an unconditional decrement and increment (although they occur in the opposite order). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: David Brownell <david-b@pacbell.net> Tested-by: Manuel Lauss <manuel.lauss@gmail.com> Tested-by: Matthijs Kooijman <matthijs@stdin.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| atm | ||
| c67x00 | ||
| class | ||
| core | ||
| gadget | ||
| host | ||
| image | ||
| misc | ||
| mon | ||
| musb | ||
| otg | ||
| serial | ||
| storage | ||
| wusbcore | ||
| 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.