This patch fixes some performance bugs observed with some workloads
when unlinking EHCI queue header (QH) descriptors from the async ring
(control/bulk schedule).

The mechanism intended to defer unlinking an empty QH (so there is no
penalty in common cases where it's quickly reused) was not working as
intended.  Sometimes the unlink was scheduled:

 - too quickly ... which can be a *strong* negative effect, since
   that QH becomes unavailable for immediate re-use;

 - too slowly ... wasting DMA cycles, usually a minor issue except
   for increased bus contention and power usage;

Plus there was an extreme case of "too slowly":  a logical error in the
IAA watchdog-timer conversion meant that sometimes the unlink never
got scheduled.

The fix replaces a simple counter with a timestamp derived from the
controller's 8 KHz microframe counter, and adjusts the timer usage
for some issues associated with HZ being less than 8K.

(Based on a patch originally by Alan Stern, and good troubleshooting
from  Leonid.)
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Leonid <leonidv11@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch fixes a regression in the EHCI driver's TIMER_IO_WATCHDOG
behavior.  The patch "USB: EHCI: add separate IAA watchdog timer" changed
how that timer is handled, so that short timeouts on the remaining
timer (unfortunately, overloaded) would never be used.

This takes a more direct approach, reorganizing the code slightly to
be explicit about only the I/O watchdog role now being overridable.
It also replaces a now-obsolete comment describing older timer behavior.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Leonid <leonidv11@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1097) fixes a bug in the remote-wakeup handling in
ehci-hcd.  The driver currently does not keep track of whether the
change-suspend feature is enabled for each port; the feature is
automatically reset the first time it is read.  But recent changes to
the hub driver require that the feature be read at least twice in
order to work properly.

A bit-vector is added for storing the change-suspend feature values.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1095) cleans up the HCD glue and several of the EHCI
bus-glue files.  The ehci->is_tdi_rh_tt flag is redundant, since it
means the same thing as the hcd->has_tt flag, so it is removed and the
other flag used in its place.

Some of the bus-glue files didn't get the relinquish_port method added
to their hc_driver structures.  Although that routine currently
doesn't do anything for controllers with an integrated TT, in the
future it might.  So the patch adds it where it is missing.

Lastly, some of the bus-glue files have erroneous entries for their
hc_driver's suspend and resume methods.  These method pointers are
specific to PCI and shouldn't be used otherwise.

(The patch also includes an invisible whitespace fix.)
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>

While most isochronous endpoints have short polling intervals, the
EHCI driver won't necessarily handle larger ones correctly.

This patch switches to use a "u16" to represent those periods, not
a u8, since it can always work:  the largest expressible period
is 2^15 units ... not the previous too-short limit of 128 frames
(full or low speeds) or microframes (high speed, 32 frames).

This bug is essentially theoretical, since the few ISO endpoints
I've seen which don't use one transfer per frame are high speed
ones using more than that (including high bandwidth, 24 KB/msec).
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

In the EHCI driver, itd->usecs[8] is used in periodic_usecs(), indexed by
uframe.  For an ITD's unused uframes it is 0, else it contains the same
value as itd->stream->usecs.  To check if an ITD's uframe is used, we can
instead test itd->hw_transaction[uframe]:  if used, it will be nonzero no
matter what endianess is used.

This patch replaces those two uses, eliminates itd->usecs[], and saves
eight bytes from each ITD.
Signed-off-by: NKarsten Wiese <fzu@wemgehoertderstaat.de>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

EHCI Glue driver for Intel IXP4XX EHCI USB controller
Signed-off-by: NVladimir Barinov <vbarinov@ru.mvista.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This adds device-tree-aware ehci-ppc-of driver.
The code is based on the ehci-ppc-soc driver by
Stefan Roese <sr@denx.de>.
Signed-off-by: NValentine Barshak <vbarshak@ru.mvista.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NStefan Roese <sr@denx.de>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1028) was mostly written by David Brownell; I made only
a few changes (extra log info and a small bug fix -- which might
account for why David's version had to be reverted).  It adds a new
watchdog timer to the ehci-hcd driver to be used exclusively for
detecting lost or missing IAA notifications.

Previously a shared timer had been used, which may have led to some
problems as reported by Christian Hoffmann.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We should not have multiple line files in sysfs, this moves the data to
debugfs instead, like the UHCI driver.
Signed-off-by: NTony Jones <tonyj@suse.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This reverts commit 196705c9.  It was
reported to cause a regression by Daniel Exner, and Arjan van de Ven
points out that we actually already have infrastructure in place for
setting limits on acceptable DMA latency that would be the much more
correct fix for the problem with some Broadcom EHCI controllers.

Fixed up trivial conflicts due to the changes to support big-endian host
controller descriptors in drivers/usb/host/{ehci-sched.c,ehci.h}.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch fixes the endianness select for transfer buffers in EHCI
controllers that have Transaction Translator built in the hub.  Also I
cleaned it up to make rid of magic numbers.
Signed-off-by: NVladimir Barinov <vbarinov@ru.mvista.com>
Cc: <david-b@pacbell.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as887) changes the way ehci-hcd and ohci-hcd handle a loss
of VBUS power during suspend.  In order for the USB-persist facility
to work correctly, it is necessary for low- and full-speed devices
attached to a high-speed port to be handed back to the companion
controller during resume processing.

This entails three changes: adding code to ehci-hcd to perform the
handover, removing code from ohci-hcd to turn off ports during
root-hub reinit, and adding code to ohci-hcd to turn on ports during
PCI controller resume.  (Other bus glue resume methods for platforms
supporting high-speed controllers would need a similar change, if any
existed.)
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Remove atomic operations on the reference counter for EHCI queue heads.
On various platforms (including ppc7448), atomic operations are unusable
with dma-coherent memory.
Signed-off-by: NSteven J. Hill <sjhill1@rockwellcollins.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch implements supports for EHCI controllers whose in-memory
data structures are represented in big-endian format. This is needed
(unfortunately) for the AMCC PPC440EPx SoC EHCI controller; the EHCI
spec doesn't specify little-endian format, although that's what most
other implementations use.

The guts of the patch are to introduce the hc32 type and change all
references from le32 to hc32.  All access routines are converted from
cpu_to_le32(...) to cpu_to_hc32(ehci, ...) and similar for the other
"direction".  (This is the same approach used with OHCI.)

David fixed:
	Whitespace fixes; refresh against ehci cpufreq patch; move glue
	for that PPC driver to the patch adding it; fix free symbol
	capture bugs in modified "constant" macros; and make "hc32" etc
	be "le32" unless we really need the BE options, so "sparse" can
	do some real good.
Signed-off-by: NStefan Roese <sr@denx.de>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

EHCI controllers that don't cache enough microframes can get MMF errors
when CPU frequency changes occur between the start and completion of
split interrupt transactions, due to delays in reading main memory
(caused by CPU cache snoop delays).

This patch adds a cpufreq notifier to the EHCI driver that will
inactivate split interrupt transactions during frequency transitions.
It was tested on Intel ICH7 and Serverworks/Broadcom HT1000 EHCI
controllers.
Signed-off-by: NStuart Hayes <stuart_hayes@dell.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

readl() et.al. expect iomem pointer, so WTF force-cast it to normal one???
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch (as710) adds a sysfs class-device attribute file named
"companion" for EHCI controllers.  The file contains a list of port
numbers that are dedicated to the companion controller; by writing a
port number to the file the user can force a high-speed device
attached directly to the computer to run at full speed.  (As far as I
know it is not possible to do this for a device attached to an
external hub.)  A port is removed from the file by writing the
negative of its port number.

Several users have asked for this facility and it seems like a useful
thing to have.  Every now and then one runs across a device which
behaves much better at full speed than at high speed.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch fixes a warning introduced by the big endian MMIO EHCI
support patch on platforms that don't have readl_be/writel_be variants
(though mostly harmless as those are called in an if (0) statement,
but gcc still warns).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This patch implements supports for EHCI controllers whose MMIO
registers are big endian and enables that functionality for
the Toshiba SCC chip. It does _not_ add support for big endian
in-memory data structures as this is not needed for that chip
and I hope it will never be.

The guts of the patch are to convert readl(...) to
ehci_readl(ehci, ...) and similarly for register writes.
Signed-off-by: NKou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NGeoff Levand <geoffrey.levand@am.sony.com>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as738b) fixes numerous problems in the controller/root-hub
suspend/resume/remote-wakeup support in ehci-hcd:

	The bus_resume() routine should wake up only the ports that
	were suspended by bus_suspend().  Ports that were already
	suspended should remain that way.

	The interrupt mask is used to detect loss of power in the
	bus_resume() routine (if the mask is 0 then power was lost).
	However bus_suspend() always sets the mask to 0.  Instead the
	mask should retain its normal value, with port-change-detect
	interrupts disabled if remote wakeup is turned off.

	The interrupt mask should be reset to its correct value at the
	end of bus_resume() regardless of whether power was lost.

	bus_resume() reinitializes the operational registers if power
	was lost.  However those registers are not in the aux power
	well, hence they can lose their values whenever the controller
	is put into D3.  They should always be reinitialized.

	When a port-change interrupt occurs and the root hub is
	suspended, the interrupt handler should request a root-hub
	resume instead of starting up the controller all by itself.

	There's no need for the interrupt handler to request a
	root-hub resume every time a suspended port sends a
	remote-wakeup request.

	The pci_resume() method doesn't need to check for connected
	ports when deciding whether or not to reset the controller.
	It can make that decision based on whether Vaux power was
	maintained.

	Even when the controller does not need to be reset,
	pci_resume() must undo the effect of pci_suspend() by
	re-enabling the interrupt mask.

	If power was lost, pci_resume() must not call ehci_run().
	At this point the root hub is still supposed to be suspended,
	not running.  It's enough to rewrite the command register and
	set the configured_flag.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This reverts 26f953fd which caused
resume problems on the mac mini.

Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This revamps handling of the hardware "async advance" IRQ, and its watchdog
timer.  Basically it dis-entangles that important timeout from the others,
simplifying the associated state and code to make it more robust.

This reportedly improves behavior of EHCI on some systems with VIA chips,
and AFAIK won't affect non-VIA hardware.  VIA systems need this code to
recover from silcon bugs whereby the "async advance" IRQ isn't issued.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

[ ... when you have an editor set to remind you of whitespace bugs ... ]

Cosmetic EHCI changes: remove end-of-line whitespace, spaces before tabs.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If some problem occurs during ehci startup, for instance, request_irq fails,
echi hcd driver tries it best to cleanup, but fails to unregister reboot
notifier, which in turn leads to crash on reboot/poweroff.

The following patch resolves this problem by not using reboot notifiers
anymore, but instead making ehci/ohci driver get its own shutdown method.  For
PCI, it is done through pci glue, for everything else through platform driver
glue.

One downside: sa1111 does not use platform driver stuff, and does not have its
own shutdown hook, so no 'shutdown' is called for it now.  I'm not sure if it
is really necessary on that platform, though.
Signed-off-by: NAleks Gorelov <dared1st@yahoo.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

On the MPC834x processors the multiport host (MPH) EHCI controller has an
erratum in which the port number in the queue head expects to be 0..N-1
instead of 1..N.  If we are on one of these chips we subtract one from
the port number before putting it into the queue head.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This teaches the EHCI driver about a quirk seen in older NForce2 chips,
adding a workaround to ignore selective suspend requests.  Bus-wide
(so-called "global") suspend still works, as does USB wakeup of a
root hub that's globally suspended.

There's still a hole in this support though.  Strictly speaking, this
should _fail_ selective suspend requests, rather than ignoring them,
since doing it this way means that devices which should be able to issue
remote wakeup are not going to be able to do that.  For now, we'll just
live with that problem ... since usbcore expects to do selective suspend
on the way towards a full bus suspend, and usbcore needs to be able to
do full bus suspend.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This splits BIOS and PCI specific support out of ehci-hcd.c into
ehci-pci.c.  It follows the model already used in the OHCI driver
so support for non-PCI EHCI controllers can be more easily added.
Signed-off-by: NMatt Porter <mporter@kernel.crashing.org>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/host/ehci-hcd.c |  543 ++++++--------------------------------------
 drivers/usb/host/ehci-pci.c |  414 +++++++++++++++++++++++++++++++++
 drivers/usb/host/ehci.h     |    1
 3 files changed, 492 insertions(+), 466 deletions(-)

One change may improve some S1 or S3 resume cases, and the other
seems mostly to explain some strange state "lsusb" would show.
Two fixes:

  - On resume, don't think about resuming any unpowered port, or
    resetting any port with OWNER set to the OHCI/UHCI companion.
    This will make some S1 and S3 resume scenarios work better.

  - PORT_CSC was not being cleared correctly in ehci_hub_status_data.
    This was visible at least through current versions of "lsusb",
    and might have caused some other hub related strangeness.

    The fix addresses all three write-to-clear bits, using the same
    approach that UHCI happens to use:  a mask of bits that are
    cleared in most writes to that port status register.

Original patch seems to have been from from William.Morrow@amd.com
and this version (from David) finishes the write-to-clear changes.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This adds the field tt_usecs to ehci_qh and ehci_iso_stream, and sets it
appropriately when setting them up as periodic endpoints.  It records
the transation translator's think_time (added in last patch) plus the
downstream (i.e. low or full speed) bustime of the transfer associated
with each interrupt or iso frame, as calculated by usb_calc_bus_time.
Signed-off-by: NDan Streetman <ddstreet@ieee.org>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch has a one line oops fix, plus related cleanups.

 - The bugfix uses microframe scheduling data given to the hardware to
   test "is this a periodic QH", rather than testing for nonzero period.
   (Prevents an oops by providing the correct answer.)

 - The cleanup going along with the patch should make it clearer what's
   going on whenever those bitfields are accessed.

The bug came about when, around January, two new kinds of EHCI interrupt
scheduling operation were added, involving both the high speed (24 KBytes
per millisec) and low/full speed (1-64 bytes per millisec) microframe
scheduling.  A driver for the Edirol UA-1000 Audio Capture Unit ran into
the oops; it used one of the newly supported high speed modes.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Miscellaneous updates for EHCI.

 - Mostly updates the power switching on EHCI controllers.  One routine
   centralizes the "power on/off all ports" logic, and the capability to
   do that is reported more correctly.

 - Courtesy Colin Leroy, a patch to always power up ports after resumes
   which didn't keep a USB device suspended.  The reset-everything logic
   powers down those ports (on some hardware) so something needs to turn
   them back on.

 - Minor tweaks/bugfixes for the debug port support.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch includes minor "sparse -Wbitwise" updates for the PCI based
HCDs.  Almost all of them involve just changing the second parameter of the
suspend() method to a pm_message_t ...  the others relate to how the EHCI
code walks in-memory data structures.  (There's a minor bug fixed there too
...  affecting the big-endian sysfs async schedule dump.)
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>


Index: gregkh-2.6/drivers/usb/core/hcd.h
===================================================================

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!