This patch (as1583) changes ehci-hcd to use an hrtimer event for
unlinking empty (unused) async QHs instead of using a kernel timer.

The check for empty QHs is moved to a new routine, where it doesn't
require going through an entire scan of both the async and periodic
schedules.  And it can unlink multiple QHs at once, unlike the current
code.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1582) changes ehci-hcd's strategy for unlinking async
QHs.  Currently the driver never unlinks more than one QH at a time.
This can be inefficient and cause unnecessary delays, since a QH
cannot be reused while it is waiting to be unlinked.

The new strategy unlinks all the waiting QHs at once.  In practice the
improvement won't be very big, because it's somewhat uncommon to have
two or more QHs waiting to be unlinked at any time.  But it does
happen, and in any case, doing things this way makes more sense IMO.

The change requires the async unlinking code to be refactored
slightly.  Now in addition to the routines for starting and ending an
unlink, there are new routines for unlinking a single QH and starting
an IAA cycle.  This approach is needed because there are two separate
paths for unlinking async QHs:

	When a transfer error occurs or an URB is cancelled, the QH
	must be unlinked right away;

	When a QH has been idle sufficiently long, it is unlinked
	to avoid consuming DMA bandwidth uselessly.

In the first case we want the unlink to proceed as quickly as
possible, whereas in the second case we can afford to batch several
QHs together and unlink them all at once.  Hence the division of
labor.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1581) replaces the iaa_watchdog kernel timer used by
ehci-hcd with an hrtimer event, in keeping with the general conversion
to high-res timers.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1580) makes ehci_iso_stream structures behave more like
QHs, in that they will remain allocated until their isochronous
endpoint is disabled.  This will come in useful in the future, when
periodic bandwidth gets allocated as an altsetting is installed rather
than on-the-fly.

For now, the change to the ehci_iso_stream lifetimes means that each
structure is always deallocated at exactly one spot in
ehci_endpoint_disable() and never used again.  As a result, it is no
longer necessary to use reference counting on these things, and the
patch removes it.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1579) adds an hrtimer event to handle deallocation of
iTDs and siTDs in ehci-hcd.

Because of the frame-oriented approach used by the EHCI periodic
schedule, the hardware can continue to access the Transfer Descriptor
for isochronous (or split-isochronous) transactions for up to a
millisecond after the transaction completes.  The iTD (or siTD) must
not be reused before then.

The strategy currently used involves putting completed iTDs on a list
of cached entries and every so often returning them to the endpoint's
free list.  The new strategy reduces overhead by putting completed
iTDs back on the free list immediately, although they are not reused
until it is safe to do so.

When the isochronous endpoint stops (its queue becomes empty), the
iTDs on its free list get moved to a global list, from which they will
be deallocated after a minimum of 2 ms.  This delay is what the new
hrtimer event is for.

Overall this may not be a tremendous improvement over the current
code, but to me it seems a lot more clear and logical.  In addition,
it removes the need for each iTD to keep a reference to the
ehci_iso_stream it belongs to, since the iTD never needs to be moved
back to the stream's free list from the global list.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1578) adds an hrtimer event to handle the death of an
EHCI controller.  When a controller dies, it doesn't necessarily stop
running right away.  The new event polls at 1-ms intervals to see when
all activity has safely stopped.  This replaces a busy-wait polling
loop in the current code.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1577) adds hrtimer support for unlinking interrupt QHs
in ehci-hcd.  The current code relies on a fixed delay of either 2 or
55 us, which is not always adequate and in any case is totally bogus.
Thanks to internal caching, the EHCI hardware may continue to access
an interrupt QH for more than a millisecond after it has been unlinked.

In fact, the EHCI spec doesn't say how long to wait before using an
unlinked interrupt QH.  The patch sets the delay to 9 microframes
minimum, which ought to be adequate.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1576) adds hrtimer support for managing ehci-hcd's
async schedule.  Just as with the earlier change to the periodic
schedule management, two new hrtimer events take care of everything.

One event polls at 1-ms intervals to see when the Asynchronous
Schedule Status (ASS) flag matches the Asynchronous Schedule Enable
(ASE) value; the schedule's state must not be changed until it does.
The other event delays for 15 ms after the async schedule becomes
empty before turning it off.

The new events replace a busy-wait poll and a kernel timer usage.
They also replace the rather illogical method currently used for
indicating the async schedule should be turned off: attempting to
unlink the dedicated QH at the head of the async list.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1575) removes special code added for status polling of
the EHCI controller in PS3 systems.  While the controller is running,
the polling is now carried out by an hrtimer handler.  When the
controller is suspending or stopping, we use the same polling routine
as the old code -- but in neither case do we need to conclude that the
controller has died if the polling goes on for too long.

As a result the entire handshake_on_error_set_halt() routine is now
unused, so it is removed from the driver.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1573) adds hrtimer support for managing ehci-hcd's
periodic schedule.  There are two issues to deal with.

First, the schedule's state (on or off) must not be changed until the
hardware status has caught up with the current command.  This is
handled by an hrtimer event that polls at 1-ms intervals to see when
the Periodic Schedule Status (PSS) flag matches the Periodic Schedule
Enable (PSE) value.

Second, the schedule should not be turned off as soon as it becomes
empty.  Turning the schedule on and off takes time, so we want to wait
until the schedule has been empty for a suitable period before turning
it off.  This is handled by an hrtimer event that gets set to expire
10 ms after the periodic schedule becomes empty.

The existing code polls (for up to 1125 us and with interrupts
disabled!) to check the status, and doesn't implement a delay before
turning off the schedule.  Furthermore, if the polling fails then the
driver decides that the controller has died.  This has caused problems
for several people; some controllers can take 10 ms or more to turn
off their periodic schedules.

This patch fixes these issues.  It also makes the "broken_periodic"
workaround unnecessary; there is no longer any danger of turning off
the periodic schedule after it has been on for less than 1 ms.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1572) begins the conversion of ehci-hcd over to using
high-resolution timers rather than old-fashioned low-resolution kernel
timers.  This reduces overhead caused by timer roundoff on systems
where HZ is smaller than 1000.  Also, the new timer framework
introduced here is much more logical and easily extended than the
ad-hoc approach ehci-hcd currently uses for timers.

An hrtimer structure is added to ehci_hcd, along with a bitflag array
and an array of ktime_t values, to keep track of which timing events
are pending and what their expiration times are.

Only the infrastructure for the timing operations is added in this
patch.  Later patches will add routines for handling each of the
various timing events the driver needs.  In some cases the new hrtimer
handlers will replace the existing handlers for ehci-hcd's kernel
timers; as this happens the old timers will be removed.  In other
cases the new timing events will replace busy-wait loops.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1571) adds a new state for ehci-hcd's root hubs:
EHCI_RH_STOPPING.  This value is used at times when the root hub is
being stopped and we don't know whether or not the hardware has
finished all its DMA yet.

Although the purpose may not be apparent, this distinction will come
in useful later on.  Future patches will avoid actions that depend on
the root hub being operational (like turning on the async or periodic
schedules) when they see the state is EHCI_RH_STOPPING.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1570) adds a pointer for the end of ehci-hcd's
async-unlink list.  The list (which is actually a queue) is singly
linked, so having a pointer to its end makes adding new entries easier
-- there's no longer any need to scan through the whole list.

In principle it could be changed to a standard doubly-linked list.  It
turns out that doing so actually makes the code less clear, so I'm
leaving it as is.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1569) renames the ehci->reclaim list in ehci-hcd.  The
word "reclaim" is used in the EHCI specification to mean something
quite different, and "unlink_next" is more descriptive of the list's
purpose anyway.

Similarly, the "reclaim" field in the ehci_stats structure is renamed
"iaa", which is more meaningful (to experts, anyway) and is a better
match for the "lost_iaa" field.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1568) introduces symbolic constants for some of the
less-frequently used bitfields in the QH structure.  This makes the
code a little easier to read and understand.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1567) removes ehci-hcd's reference counting of QH
structures.  It's not necessary to refcount these things because they
always get deallocated at exactly one spot in ehci_endpoint_disable()
(except for two special QHs, ehci->async and ehci->dummy) and are
never used again.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1566) removes the code in ehci-hcd's resume routines
which tries to restart or cancel any transfers left active while the
root hub or controller was asleep.  This code isn't necessary, because
all URBs are terminated before the root hub is suspended.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently, EHCI initialization turns off the controller (in case it
was left running by the firmware) before setting up the ehci_hcd data
structure.  This patch (as1565) reverses that order.

Although it doesn't matter now, it will matter later on when future
additions to ehci_halt() will want to acquire a spinlock that gets
initialized by ehci_init().
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1564c) converts the EHCI platform drivers to use the
central ehci_setup() routine for generic controller initialization
rather than each having its own idiosyncratic approach.

The major point of difficulty lies in ehci-pci's many vendor- and
device-specific workarounds.  Some of them have to be applied before
calling ehci_setup() and some after, which necessitates a fair amount
of code motion.  The other platform drivers require much smaller
changes.

One point not addressed by the patch is whether ports should be
powered on or off following initialization.  The different drivers
appear to handle this pretty much at random.  In fact it shouldn't
matter, because the hub driver turns on power to all ports when it
binds to the root hub.  Straightening that out will be left for
another day.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1563) removes a lot of duplicated code by moving the
EHCI controller suspend/resume routines into the core driver, where
the various platform drivers can invoke them as needed.

Not only does this simplify these platform drivers, this also makes it
easier for other platform drivers to add suspend/resume support in the
future.

Note: The patch does not touch the ehci-fsl.c file, because its
approach to suspend and resume is so different from all the others.
It will have to be handled specially by its maintainer.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1562) cleans up the definitions of the EHCI extended
registers to be consistent with the definitions of the standard
registers.  This makes the code look a lot nicer, with no functional
change.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After commit aaa0ef28 "PS3 EHCI QH
read work-around", Terratec Grabby (em28xx) stopped working with AMD
Geode LX 800 (USB controller AMD CS5536). Since this is a PS3 only
fix, the following patch adds a conditional block around it.
Signed-off-by: NRicardo Martins <rasm@fe.up.pt>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 1996e6c5.

It turned out to not be needed, now that the real fix has been
committed.
Reported-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The 3d9545cc(EHCI: maintain the
ehci->command value properly) introducs one command register
configuration lost problem by the below line in ehci_reset:

	ehci->command = ehci_readl(ehci, &ehci->regs->command);

After writting RESET into command register, it is restored to
its default value per EHCI spec[1], so the previous configuration
will be lost, and may introduce some problems reported recently:
	- imx51 Babbage board detect usb hub failed[2], reported
	by Richard Zhao.
	- mouse and keyboard hangs in linux-next found by
	Dan Carpenter and Greg-KH.

So this patch just removes the line to fix these problems, and
keep configurating command register consistent as before the commit
3d9545cc(EHCI: maintain the ehci->command value properly).

[1], 4.1 Host Controller Initialization of EHCI Specification 1.0
[2], failed dmesg log:
	usb 1-1: new high-speed USB device number 2 using mxc-ehci
	hub 1-1:1.0: USB hub found
	hub 1-1:1.0: 7 ports detected
	mxc-ehci mxc-ehci.1: fatal error
	mxc-ehci mxc-ehci.1: HC died; cleaning up
	mxc-ehci mxc-ehci.1: force halt; handshake f5780344 00004000 00004000 -> -110
	mxc-ehci mxc-ehci.1: HC died; cleaning up
	usb 1-1: USB disconnect, device number 2
Reported-by: NRichard Zhao <richard.zhao@freescale.com>
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Reported-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Chen Peter-B29397 <B29397@freescale.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1556) works around a bug in the Philips ISP1562 EHCI
controller.  Although the controller claims to support frame-list
lengths smaller than the default of 1024 for its periodic schedule, in
fact smaller values don't work.  A new quirk flag is added to indicate
when the bug is present, and if it is then the schedule size is left
at the default value.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds EHCI host support to the chipidea driver. We want it to be
part of the hdrc driver and not a standalone (sub-)driver module, as
the structure of ehci-hcd.c suggests, so for chipidea controller we
hack it to not provide platform-related code, but only the ehci hcd.

The ehci-platform driver won't work for us here too, because the
controller uses the same registers for both device and host mode and
also otg-related bits, so it's not really possible to put ehci registers
into a separate resource.

This is not a pretty solution, but the alternative is exporting symbols
from the chipidea driver to a ehci-chipidea driver and doing all the
module refcounting.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The ehci-hcd driver is a little haphazard about keeping track of the
state of the USBCMD register.  The ehci->command field is supposed to
hold the register's value (apart from a few special bits) at all
times, but it isn't maintained properly.

This patch (as1543) cleans up the situation.  It keeps ehci->command
up-to-date, and uses that value rather than reading the register from
the hardware whenever possible.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add EHCI driver for MIPS SEAD-3 development platform.
Signed-off-by: NChris Dearman <chris@mips.com>
Signed-off-by: NSteven J. Hill <sjhill@mips.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1541) corrects a small mistake in ehci-hcd.  The IAAD
(Interrupt on Async Advance Doorbell) bit in the USBCMD register is
designed, as its name says, to act as a "doorbell".  That is, the
driver activates the bit by setting it to 1, and the hardware
deactivates it later by setting it back to 0.  The driver cannot clear
the bit by writing a 0 to it; such writes are simply ignored.

Therefore there is no reason for ehci-hcd to try to clear the bit.
The patch removes the two instances where such attempts occur.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1544) fixes a problem affecting some EHCI controllers.
They can generate interrupts whenever the STS_FLR status bit is turned
on, even though that bit is masked out in the Interrupt Enable
register.

Since the driver doesn't use STS_FLR anyway, the patch changes the
interrupt routine to clear that bit whenever it is set, rather than
leaving it alone.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: NTomoya MORINAGA <tomoya.rohm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1542) changes the criterion ehci-hcd uses to tell when
it needs to resume the controller's root hub.  A resume is needed when
a port status change is detected, obviously, but only if the root hub
is currently suspended.

Right now the driver tests whether the root hub is running, and that
is not the correct test.  In particular, if the controller has died
then the root hub should not be restarted.  In addition, some buggy
hardware occasionally requires the root hub to be running and
sending out SOF packets even while it is nominally supposed to be
suspended.

In the end, the test needs to be changed.  Rather than checking whether
the root hub is currently running, the driver will now check whether
the root hub is currently suspended.  This will yield the correct
behavior in all cases.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
CC: Peter Chen <B29397@freescale.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1537) adds a bit-array to ehci-hcd for keeping track of
which ports are undergoing a resume transition.  If any of the bits
are set when ehci_hub_status_data() is called, the routine will return
a nonzero value even if no ports have any status changes pending.
This will allow usbcore to handle races between root-hub suspend and
port wakeup.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
CC: Chen Peter-B29397 <B29397@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

The ath79 usb driver doesn't do anything special and is now converted
to the generic ehci and ohci driver.
This was tested on a TP-Link TL-WR1043ND (AR9132)
Acked-by: NGabor Juhos <juhosg@openwrt.org>
CC: Imre Kaloz <kaloz@openwrt.org>
CC: linux-mips@linux-mips.org
CC: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds a generic driver for platform devices. It works like the PCI
driver and is based on it. This is for devices which do not have an own
bus but their EHCI controller works like a PCI controller. It will be
used for the Broadcom bcma and ssb USB EHCI controller.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since ehci-mv.c can cover Marvell PXA and MMP series including PXA168,
so this driver seems redundant now.
Signed-off-by: NNeil Zhang <zhangwm@marvell.com>
Cc: <tanmay.upadhyay@einfochips.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use ehci_setup() in ehci_ls1x_reset().

The Loongson1x SoCs have a built-in EHCI controller.
This patch adds the necessary glue code to make the generic EHCI
driver usable for them.
Signed-off-by: NKelvin Cheung <keguang.zhang@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This patch adds support for EHCI compliant HSUSB Host controller found
on Marvell Socs.

It fits both OTG and SPH controller on marvell Socs, including
PXA9xx/MMP2/MMP3/MGx.
Signed-off-by: NNeil Zhang <zhangwm@marvell.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

PS3 EHCI HC errata fix 244.  The SCC EHCI HC will not correctly perform QH
reads that occur near or span a micro-frame boundry.  This is due to a problem
in the Nak Count Reload Control logic (EHCI Specification 1.0 Section 4.9.1).

The work-around for this problem is for the HC driver to set I=1 (inactive) for
QHs with H=1 (list head).
Signed-off-by: NGeoff Levand <geoff@infradead.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>