Some morph devices will morph after being reset and cause persist
to fail. This patch is to add descriptor about this in the
Document/usb/persist.txt
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1109b) makes USB-Persist more resilient to errors. With
the current code, if a normal resume fails, it's an unrecoverable
error. With the patch, if a normal resume fails (and if the device is
enabled for USB-Persist) then a reset-resume is tried.
This fixes the problem reported in Bugzilla #10977.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1048) extends the descriptor checking after a device is
reset. Now the SerialNumber string descriptor is compared to its old
value, in addition to the device and configuration descriptors.
As a consequence, the kmalloc() call in usb_string() is now on the
error-handling pathway for usb-storage. Hence its allocation type is
changed to GFO_NOIO.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1047) removes the USB_PERSIST Kconfig option, enabling
it permanently. It also prevents the power/persist attribute from
being created for hub devices; there's no point in having it since
USB-PERSIST is always turned on for hubs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as920) adds an extra level of protection to the
USB-Persist facility. Now it will apply by default only to hubs; for
all other devices the user must enable it explicitly by setting the
power/persist device attribute.
The disconnect_all_children() routine in hub.c has been removed and
its code placed inline. This is the way it was originally as part of
hub_pre_reset(); the revised usage in hub_reset_resume() is
sufficiently different that the code can no longer be shared.
Likewise, mark_children_for_reset() is now inline as part of
hub_reset_resume(). The end result looks much cleaner than before.
The sysfs interface is updated to add the new attribute file, and
there are corresponding documentation updates.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as886) adds the controversial USB-persist facility,
allowing USB devices to persist across a power loss during system
suspend.
The facility is controlled by a new Kconfig option (with appropriate
warnings about the potential dangers); when the option is off the
behavior will remain the same as it is now. But when the option is
on, people will be able to use suspend-to-disk and keep their USB
filesystems intact -- something particularly valuable for small
machines where the root filesystem is on a USB device!
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Lan Tianyu