On Sun, Feb 2, 2014 at 1:35 AM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Sat, Feb 01, 2014 at 11:16:24AM -0800, Dan Williams wrote:
>> On Sat, Feb 1, 2014 at 10:44 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
>> > On Fri, 31 Jan 2014, Dan Williams wrote:
>> >
>> >> Toggling port power currently leads to three unintended disconnect
>> >> scenarios that are addressed by this rework of port power recovery and
>> >> usb device resume:
>> >>
>> >> 1/ Superspeed devices downgrade to their hispeed connection: fix this by
>> >> preventing superspeed poweroff until the peer port is suspended.
>> >> This depends on the ability to identify peer ports (patches 1-4), and
>> >> then patch 5 implements the policy.
>> >>
>> >> 2/ khubd prematurely disconnects ports that are in the process of
>> >> being resumed or reset. khubd now ignores ports in the
>> >> pm-runtime-suspended state (patch 9) and holds a lock to synchronize the port
>> >> status changes of usb_port_{suspend|resume} (patch 11).
>> >>
>> >> 3/ Superspeed devices fail to reconnect: Seen during repeated toggles of
>> >> the port power state. Fixed by forcing a full recovery cycle of the
>> >> usb_device before allowing the next suspend / khubd run (patch 12).
>> >> Also, for devices that live lock on reconnect the port runtime resume
>> >> path now has the capability to force a reset-resume to be a
>> >> warm-reset-resume (patch 13).
>> >
>> > I haven't gone through all this in any detail. But a couple of things
>> > stand out immediately, matters of style.
>> >
>> > Although the USB stack still has plenty of old code with multiline
>> > comments looking this this:
>> >
>> > /* blah blah blah
>> > * blah blah blah
>> > */
>> >
>> > the accepted style is that all new code should appear like this:
>> >
>> > /*
>> > * blah blah blah
>> > * blah blah blah
>> > */
>>
>> Ah, the eternal debate. No worries.
>>
>> > Also, the style for indentation througout most of the USB stack is that
>> > continuation lines are indented by two tab stops beyond the first line
>> > of the statement. They are not aligned with opening parentheses of
>> > function calls or anything like that.
>>
>> Unfortunate that what goes for net/, or drivers/md/ doesn't go for
>> drivers/usb/... sounds like checkpatch needs subsystem specific style
>> rules to avoid this thrash.
>>
>> If it's just the style I'll put those changes on a git branch and
>> spare the list if you're ok doing a pull... otherwise I'll hold off
>> until you have a chance to take a closer look.
>
> I don't do git pulls except from a very few number of people, so you
> will have to make these into "real" patches eventually if you want them
> to be accepted.
Ok, that's the plan once Alan let's me know if v5 needs more than just
the style changes. Until then the git tree is just a convenience for
review.
--
Dan
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