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04e51901dd
This patch implements isochronous urb enqueue and interrupt handler part. When an isochronous urb is passed to xHCI driver, first check the transfer ring to guarantee there is enough room for the whole urb. Then update the start_frame and interval field of the urb. Always assume URB_ISO_ASAP is set, and never use urb->start_frame as input. The number of isoc TDs is equal to urb->number_of_packets. One isoc TD is consumed every Interval. Each isoc TD consists of an Isoch TRB chained to zero or more Normal TRBs. Call prepare_transfer for each TD to do initialization; then calculate the number of TRBs needed for each TD. If the data required by an isoc TD is physically contiguous (not crosses a page boundary), then only one isoc TRB is needed; otherwise one or more additional normal TRB shall be chained to the isoc TRB by the host. Set TRB_IOC to the last TRB of each isoc TD. Do not ring endpoint doorbell to start xHC procession until all the TDs are inserted to the endpoint transer ring. In irq handler, update urb status and actual_length, increase urb_priv->td_cnt. When all the TDs are completed(td_cnt is equal to urb_priv->length), giveback the urb to usbcore. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| c67x00 | ||
| class | ||
| core | ||
| early | ||
| 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.