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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit aaa0ef289a "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: Ricardo Martins <rasm@fe.up.pt>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 1996e6c572.
It turned out to not be needed, now that the real fix has been
committed.
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 3d9545cc375d117554a9b35dfddadf9189c62775(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: Richard Zhao <richard.zhao@freescale.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Chen Peter-B29397 <B29397@freescale.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg 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: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This resolves the conflict in:
drivers/usb/host/ehci-fsl.c
And picks up loads of xhci bugfixes to make it easier for others to test
with.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add EHCI driver for MIPS SEAD-3 development platform.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
CC: Peter Chen <B29397@freescale.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
CC: Chen Peter-B29397 <B29397@freescale.com>
Signed-off-by: Greg 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: David 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: Gabor 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: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Greg 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: Neil Zhang <zhangwm@marvell.com>
Cc: <tanmay.upadhyay@einfochips.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg 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: Kelvin Cheung <keguang.zhang@gmail.com>
Signed-off-by: Greg 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: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty 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: Neil Zhang <zhangwm@marvell.com>
Signed-off-by: Felipe 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: Geoff Levand <geoff@infradead.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
The EHCI USB controller of the Cell Super Companion Chip used in the PS3
will stop the root hub after all root hub ports are suspended. When in
this condition the ehci-hcd handshake routine will return -ETIMEDOUT and
the USB runtime suspend sequence will fail. The STS_HLT bit will not be
set, so inspection of the frame index is used to test for the condition.
Add a new routine handshake_for_broken_root_hub() that is called after
an unsuccessful -ETIMEDOUT handshake. On PS3 handshake_for_broken_root_hub()
will test for the condition, and if found will return success to allow the
USB suspend to complete. For all other platforms
handshake_for_broken_root_hub() will return -ETIMEDOUT
Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Remove the ehci_reset() call done in the ehci_run() routine of the
USB EHCI host controller driver and add an ehci_reset() call to the
probe processing of all EHCI platform drivers that do not already call
ehci_reset().
The call to ehci_reset() from ehci_run() was problematic for several
platform drivers, and unnecessary for others. This change moves the
decision to call ehci_reset() at driver startup to the platform
driver code.
Signed-off-by: Geoff Levand <geoff@infradead.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Use CONFIG_CPU_XLR instead of CONFIG_NLM_XLR, the NLM_XLR config
option is redundant and is being removed.
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now that no driver any longer depends on the CONFIG_SOC_AU1??? symbols,
it's time to get rid of them: Move some of the platform devices to the
boards which can use them, Rename a few (unused) constants in the header,
Replace them with MIPS_ALCHEMY in the various Kconfig files. Finally
delete them altogether from the Alchemy Kconfig file.
Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/2707/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch (as1489) works around a hardware bug in MosChip EHCI
controllers. Evidently when one of these controllers increments the
frame-index register, it changes the three low-order bits (the
microframe counter) before changing the higher order bits (the frame
counter). If the register is read at just the wrong time, the value
obtained is too low by 8.
When the appropriate quirk flag is set, we work around this problem by
reading the frame-index register a second time if the first value's
three low-order bits are all 0. This gives the hardware a chance to
finish updating the register, yielding the correct value.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Jason N Pitt <jpitt@fhcrc.org>
CC: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
EHCI_SHRINK_JIFFIES should be 5ms, which was just used originally,
and not 200ms, so fix it.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1483) improves the ehci-hcd driver family by getting rid
of the reliance on the hcd->state variable. It has no clear owner and
it isn't protected by the usual HCD locks. In its place, the patch
adds a new, private ehci->rh_state field to record the state of the
root hub.
Along the way, the patch removes a couple of lines containing
redundant assignments to the state variable. Also, the QUIESCING
state simply gets changed to the RUNNING state, because the driver
doesn't make any distinction between them.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add supprt for on-chip USB controller for Netlogic XLS MIPS64
SoC processor family.
Changes are:
- update ehci-hcd.c and ohci-hcd.c to add XLS hcds
- add ehci-xls.c: EHCI support for Netlogic XLS.
- add ohci-xls.c: OHCI support for Netlogic XLS.
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (115 commits)
EHCI: fix direction handling for interrupt data toggles
USB: serial: add IDs for WinChipHead USB->RS232 adapter
USB: OHCI: fix another regression for NVIDIA controllers
usb: gadget: m66592-udc: add pullup function
usb: gadget: m66592-udc: add function for external controller
usb: gadget: r8a66597-udc: add pullup function
usb: renesas_usbhs: support multi driver
usb: renesas_usbhs: inaccessible pipe is not an error
usb: renesas_usbhs: care buff alignment when dma handler
USB: PL2303: correctly handle baudrates above 115200
usb: r8a66597-hcd: fixup USB_PORT_STAT_C_SUSPEND shift
usb: renesas_usbhs: compile/config are rescued
usb: renesas_usbhs: fixup comment-out
usb: update email address in ohci-sh and r8a66597-hcd
usb: r8a66597-hcd: add function for external controller
EHCI: only power off port if over-current is active
USB: mon: Allow to use usbmon without debugfs
USB: EHCI: go back to using the system clock for QH unlinks
ehci: add pci quirk for Ordissimo and RM Slate 100 too
ehci: refactor pci quirk to use standard dmi_check_system method
...
Fix up trivial conflicts in Documentation/feature-removal-schedule.txt
This patch (as1477) fixes a problem affecting a few types of EHCI
controller. Contrary to what one might expect, these controllers
automatically stop their internal frame counter when no ports are
enabled. Since ehci-hcd currently relies on the frame counter for
determining when it should unlink QHs from the async schedule, those
controllers run into trouble: The frame counter stops and the QHs
never get unlinked.
Some systems have also experienced other problems traced back to
commit b963801164 (USB: ehci-hcd unlink
speedups), which made the original switch from using the system clock
to using the frame counter. It never became clear what the reason was
for these problems, but evidently it is related to use of the frame
counter.
To fix all these problems, this patch more or less reverts that commit
and goes back to using the system clock. But this can't be done
cleanly because other changes have since been made to the scan_async()
subroutine. One of these changes involved the tricky logic that tries
to avoid rescanning QHs that have already been seen when the scanning
loop is restarted, which happens whenever an URB is given back.
Switching back to clock-based unlinks would make this logic even more
complicated.
Therefore the new code doesn't rescan the entire async list whenever a
giveback occurs. Instead it rescans only the current QH and continues
on from there. This requires the use of a separate pointer to keep
track of the next QH to scan, since the current QH may be unlinked
while the scanning is in progress. That new pointer must be global,
so that it can be adjusted forward whenever the _next_ QH gets
unlinked. (uhci-hcd uses this same trick.)
Simplification of the scanning loop removes a level of indentation,
which accounts for the size of the patch. The amount of code changed
is relatively small, and it isn't exactly a reversion of the
b963801164 commit.
This fixes Bugzilla #32432.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@kernel.org>
Tested-by: Matej Kenda <matejken@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are cases, when 80% max isochronous bandwidth is too limiting.
For example I have two USB video capture cards which stream uncompressed
video, and to stream full NTSC + PAL videos we'd need
NTSC 640x480 YUV422 @30fps ~17.6 MB/s
PAL 720x576 YUV422 @25fps ~19.7 MB/s
isoc bandwidth.
Now, due to limited alt settings in capture devices NTSC one ends up
streaming with max_pkt_size=2688 and PAL with max_pkt_size=2892, both
with interval=1. In terms of microframe time allocation this gives
NTSC ~53us
PAL ~57us
and together
~110us > 100us == 80% of 125us uframe time.
So those two devices can't work together simultaneously because the'd
over allocate isochronous bandwidth.
80% seemed a bit arbitrary to me, and I've tried to raise it to 90% and
both devices started to work together, so I though sometimes it would be
a good idea for users to override hardcoded default of max 80% isoc
bandwidth.
After all, isn't it a user who should decide how to load the bus? If I
can live with 10% or even 5% bulk bandwidth that should be ok. I'm a USB
newcomer, but that 80% set in stone by USB 2.0 specification seems to be
chosen pretty arbitrary to me, just to serve as a reasonable default.
NOTE 1
~~~~~~
for two streams with max_pkt_size=3072 (worst case) both time
allocation would be 60us+60us=120us which is 96% periodic bandwidth
leaving 4% for bulk and control. Alan Stern suggested that bulk then
would be problematic (less than 300*8 bittimes left per microframe), but
I think that is still enough for control traffic.
NOTE 2
~~~~~~
Sarah Sharp expressed concern that maxing out periodic bandwidth
could lead to vendor-specific hardware bugs on host controllers, because
> It's entirely possible that you'll run into
> vendor-specific bugs if you try to pack the schedule with isochronous
> transfers. I don't think any hardware designer would seriously test or
> validate their hardware with a schedule that is basically a violation of
> the USB bus spec (more than 80% for periodic transfers).
So far I've only tested this patch on my HP Mini 5103 with N10 chipset
kirr@mini:~$ lspci
00:00.0 Host bridge: Intel Corporation N10 Family DMI Bridge
00:02.0 VGA compatible controller: Intel Corporation N10 Family Integrated Graphics Controller
00:02.1 Display controller: Intel Corporation N10 Family Integrated Graphics Controller
00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 02)
00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1 (rev 02)
00:1c.3 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 4 (rev 02)
00:1d.0 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 02)
00:1d.1 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 02)
00:1d.2 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 02)
00:1d.3 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 02)
00:1d.7 USB Controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2)
00:1f.0 ISA bridge: Intel Corporation NM10 Family LPC Controller (rev 02)
00:1f.2 SATA controller: Intel Corporation N10/ICH7 Family SATA AHCI Controller (rev 02)
01:00.0 Network controller: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller (rev 01)
02:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8059 PCI-E Gigabit Ethernet Controller (rev 11)
and the system works stable with 110us/uframe (~88%) isoc bandwith allocated for
above-mentioned isochronous transfers.
NOTE 3
~~~~~~
This feature is off by default. I mean max periodic bandwidth is set to
100us/uframe by default exactly as it was before the patch. So only those of us
who need the extreme settings are taking the risk - normal users who do not
alter uframe_periodic_max sysfs attribute should not see any change at all.
NOTE 4
~~~~~~
I've tried to update documentation in Documentation/ABI/ thoroughly, but
only "TBD" was put into Documentation/usb/ehci.txt -- the text there seems
to be outdated and much needing refreshing, before it could be amended.
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The only sysfs attr implemented so far is "companion" from ehci-hub.c,
but in the next patch we are going to add another sysfs file, so prior
to that let's structure things and move already-in-there sysfs code to
separate file.
NOTE: All the code I'm moving into this new file was written by Alan
Stern (in 57e06c11 "EHCI: force high-speed devices to run at full
speed"; Jan 16 2007), that's why I'm putting
Copyright (C) 2007 by Alan Stern
there after explicit request from the author.
Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
