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6b6e97107f
Multi-frame isochronous TX URBs transfers in DMA mode never complete with CPPI DMA because musb_host_tx() doesn't restart DMA on the second frame, only emitting a debug message. With Inventra DMA they complete, but in PIO mode. To fix: - Factor out programming of the DMA transfer from musb_ep_program() into musb_tx_dma_program(); - Reorder the code at the end of musb_host_tx() to facilitate the fallback to PIO iff DMA fails; - Handle the buffer offset consistently for both PIO and DMA modes; - Add an argument to musb_ep_program() for the same reason (it only worked correctly with non-zero offset of the first frame in PIO mode); - Set the completed isochronous frame descriptor's 'actual_length' and 'status' fields correctly in DMA mode. Also, since CPPI reportedly doesn't like sending isochronous packets in the RNDIS mode, change the criterion for this mode to be used only for multi-packet transfers. (There's no need for that mode in the single-packet case anyway.) [ dbrownell@users.sourceforge.net: split comment paragraph into bullet list, shrink patch delta, style tweaks ] Signed-off-by: Pavel Kiryukhin <pkiryukhin@ru.mvista.com> Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| 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.