forked from luck/tmp_suning_uos_patched
52fb61250a
The xHCI platform driver calls into usb_add_hcd to register the irq for
its platform device. It does not want the xHCI generic driver to
register an interrupt for it at all. The original code did that by
setting the XHCI_BROKEN_MSI quirk, which tells the xHCI driver to not
enable MSI or MSI-X for a PCI host.
Unfortunately, if CONFIG_PCI is enabled, and CONFIG_USB_DW3 is enabled,
the xHCI generic driver will attempt to register a legacy PCI interrupt
for the xHCI platform device in xhci_try_enable_msi(). This will result
in a bogus irq being registered, since the underlying device is a
platform_device, not a pci_device, and thus the pci_device->irq pointer
will be bogus.
Add a new quirk, XHCI_PLAT, so that the xHCI generic driver can
distinguish between a PCI device that can't handle MSI or MSI-X, and a
platform device that should not have its interrupts touched at all.
This quirk may be useful in the future, in case other corner cases like
this arise.
This patch should be backported to kernels as old as 3.9, that
contain the commit
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| .. | ||
| atm | ||
| c67x00 | ||
| chipidea | ||
| class | ||
| core | ||
| dwc3 | ||
| early | ||
| gadget | ||
| host | ||
| image | ||
| misc | ||
| mon | ||
| musb | ||
| phy | ||
| renesas_usbhs | ||
| serial | ||
| storage | ||
| wusbcore | ||
| Kconfig | ||
| Makefile | ||
| README | ||
| usb-common.c | ||
| 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.