forked from luck/tmp_suning_uos_patched
b876aef7f8
This patch is originally from Alan Stern (as557). It has been re-diffed against a current tree, and I also corrected a minor merging error. Some time ago we introduced a delay before device scanning, because many devices do not like to receive SCSI commands right after enumeration. Now it turns out there's a device that doesn't like to receive Get-Max-LUN right after enumeration either. Accordingly this patch delays the Get-Max-LUN request until the beginning of the scanning procedure. This fixes Bugzilla entry #5010. Three things are worth noting. First, I removed the locking code from usb_stor_acquire_resources. It's not needed, because the locking is to protect against disconnect events and acquire_resources is only called during probe (so the disconnect routine can't be called). Second, I initialized to 0 the buffer used for the Get-Max-LUN response. It's not really necessary, but it will prevent random values from showing up in the debugging log when the request fails. Third, I added a test against the SINGLE_LUN flag. This will allow us to use the flag to indicate Bulk-only devices that can't handle Get-Max-LUN. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| atm | ||
| class | ||
| core | ||
| gadget | ||
| host | ||
| image | ||
| input | ||
| media | ||
| misc | ||
| mon | ||
| net | ||
| serial | ||
| storage | ||
| 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.