Commit Graph

36 Commits

Author SHA1 Message Date
Sarah Sharp da13051cc7 USB: Remove bitmap #define from hcd.h
Using a #define to redefine a common variable name is a bad thing,
especially when the #define is in a header.  include/linux/usb/hcd.h
redefined bitmap to DeviceRemovable to avoid typing a long field in the
hub descriptor.  This has unintended side effects for files like
drivers/usb/core/devio.c that include that file, since another header
included after hcd.h has different variables named bitmap.

Remove the bitmap #define and replace instances of it in the host
controller code.  Cleanup the spaces around function calls and square
brackets while we're at it.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Cc: Tony Olech <tony.olech@elandigitalsystems.com>
Cc: "Robert P. J. Day" <rpjday@crashcourse.ca>
Cc: Max Vozeler <mvz@vozeler.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Rodolfo Giometti <giometti@linux.it>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Anton Vorontsov <avorontsov@mvista.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Lothar Wassmann <LW@KARO-electronics.de>
Cc: Olav Kongas <ok@artecdesign.ee>
Cc: Martin Fuzzey <mfuzzey@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <dbrownell@users.sourceforge.net>
2011-03-13 18:07:07 -07:00
Joe Perches 7f26b3a753 drivers/usb: Remove unnecessary return's from void functions
Greg prefers this to go through the trivial tree.
http://lkml.org/lkml/2010/6/24/1

There are about 2500 void functions in drivers/usb
Only a few used return; at end of function.

Standardize them a bit.

Moved a statement down a line in drivers/usb/host/u132-hcd.c

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-08-10 14:25:42 +02:00
Randy Dunlap 1d6ec813e2 USB: fix u132-hcd code/data warning
Fix gcc warning on mixed declarations/code:
drivers/usb/host/u132-hcd.c:1450: warning: ISO C90 forbids mixed declarations and code

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20 13:21:43 -07:00
Bill Pemberton 6641445c3e usb: u132-hcd.c: fix shadows sparse warning
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20 13:21:41 -07:00
Eric Lescouet 27729aadd3 USB: make hcd.h public (drivers dependency)
The usbcore headers: hcd.h and hub.h are shared between usbcore,
HCDs and a couple of other drivers (e.g. USBIP modules).
So, it makes sense to move them into a more public location and
to cleanup dependency of those modules on kernel internal headers.
This patch moves hcd.h from drivers/usb/core into include/linux/usb/

Signed-of-by: Eric Lescouet <eric@lescouet.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20 13:21:30 -07:00
Alan Stern b5fb454f69 USB: automatically enable RHSC interrupts
This patch (as1069c) changes the way OHCI root-hub status-change
interrupts are enabled.  Currently a special HCD method,
hub_irq_enable(), is called when the hub driver is finished using a
root hub.  This approach turns out to be subject to races, resulting
in unnecessary polling.

The patch does away with the method entirely.  Instead, the driver
automatically enables the RHSC interrupt when no more status changes
are present.  This scheme is safe with controllers using
level-triggered semantics for their interrupt flags.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:26:38 -07:00
Kay Sievers 7071a3ce0c USB: usb dev_name() instead of dev->bus_id
The bus_id field is going away, use the dev_name() function instead.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:15:46 -07:00
Linus Torvalds 09ca8adbe9 Revert "USB: don't explicitly reenable root-hub status interrupts"
This reverts commit e872154921.

Andrey Borzenkov reports that it resulted in a totally hung machine for
him when loading the OHCI driver.  Extensive netconsole capture with
SysRq output shows that modprobe gets stuck in ohci_hub_status_data()
when probing and enabling the OHCI controller, see for example

	http://lkml.org/lkml/2008/7/5/236

for an analysis.

The problem appears to be an interrupt flood triggered by the commit
that gets reverted, and Andrey confirmed that the revert makes things
work for him again.

Reported-and-tested-by: Andrey Borzenkov <arvidjaar@mail.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-06 10:27:25 -07:00
Alan Stern e872154921 USB: don't explicitly reenable root-hub status interrupts
This patch (as1069b) changes the way OHCI root-hub status-change
interrupts are enabled.  Currently a special HCD method,
hub_irq_enable(), is called when the hub driver is finished using a
root hub.  This approach turns out to be subject to races, resulting
in unnecessary polling.

The patch does away with the method entirely.  Instead, the driver
automatically enables the RHSC interrupt when no more status changes
are present.  This scheme is safe with controllers using
level-triggered semantics for their interrupt flags.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:53 -07:00
Alan Stern 7be7d74187 USB: clarify usage of hcd->suspend/resume methods
The .suspend and .resume method pointers in struct usb_hcd have not
been fully understood by host-controller driver writers.  They are
meant for use with PCI controllers; other platform-specific drivers
generally should not refer to them.

To try and clarify matters, this patch (as1065) renames those methods
to .pci_suspend and .pci_resume.  It eliminates corresponding dead code
and bogus references in the ohci-ssb and u132-hcd drivers.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:48 -07:00
Daniel Walker 50d8ca9b56 usb: u132-hcd driver: semaphore to mutex
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:45 -07:00
Daniel Walker b40f8d3980 usb: u132-hcd driver style clean up
I was converting a semaphore in this file to a mutex when I noticed that
this file has some fairly rampant style problems. Practically every line
has spaces instead of tabs .. Once I cleared that up, checkpatch.pl showed
a number of other problem.. I think this file might be a good one to review
for new style checks that could be added..

Below are the only two remaining which I didn't remove. 

#5083: FILE: drivers/usb/host/u132-hcd.c:2907:
+               error:

WARNING: labels should not be indented
#5087: FILE: drivers/usb/host/u132-hcd.c:2911:
+               stall:

These labels are actually inside a switch statement, and they are right
under "default:". "default:" appears to be exempt and these other label
should be too, or default shouldn't be exempt.

I also deleted a few lines due to single statements inside { } , 

if (is_error()) {
	return;
}

becomes,

if (is_error())
	return;

with one line deleted.

Signed-off-by: Daniel Walker <dwalker@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:44 -07:00
Alan Stern 70a1c9e086 USB: remove dev->power.power_state
power.power_state is scheduled for removal.  This patch (as1053)
removes all uses of that field from drivers/usb.  Almost all of them
were write-only, the most significant exceptions being sl811-hcd.c and
u132-hcd.c.

Part of this patch was written by Pavel Machek.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:41 -07:00
Kay Sievers f4fce61d41 usb host: fix platform driver hotplug/coldplug
Since 43cc71eed1, the platform modalias is
prefixed with "platform:".  Add MODULE_ALIAS() to the hotpluggable USB HCDs,
to allow re-enable auto loading.

[dbrownell@users.sourceforge.net: more drivers; registration fixes]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-11 08:06:44 -07:00
Mirco Tischler 038eb0ea04 Fix u132-hcd.c compile error
This fixes the following compile error caused by commit
3a2d5b7001 ("PM: Introduce
PM_EVENT_HIBERNATE callback state")

    CC [M]  drivers/usb/host/u132-hcd.o
  drivers/usb/host/u132-hcd.c: In function ‘u132_suspend’:
  drivers/usb/host/u132-hcd.c:3224: error: expected expression before ‘int’
  drivers/usb/host/u132-hcd.c:3225: error: ‘ports’ undeclared (first use in this function)
  ...

Signed-off-by: Mirco Tischler <mt-ml@gmx.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-23 20:29:09 -08:00
Rafael J. Wysocki 3a2d5b7001 PM: Introduce PM_EVENT_HIBERNATE callback state
During the last step of hibernation in the "platform" mode (with the
help of ACPI) we use the suspend code, including the devices'
->suspend() methods, to prepare the system for entering the ACPI S4
system sleep state.

But at least for some devices the operations performed by the
->suspend() callback in that case must be different from its operations
during regular suspend.

For this reason, introduce the new PM event type PM_EVENT_HIBERNATE and
pass it to the device drivers' ->suspend() methods during the last phase
of hibernation, so that they can distinguish this case and handle it as
appropriate.  Modify the drivers that handle PM_EVENT_SUSPEND in a
special way and need to handle PM_EVENT_HIBERNATE in the same way.

These changes are necessary to fix a hibernation regression related
to the i915 driver (ref. http://lkml.org/lkml/2008/2/22/488).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-23 10:40:04 -08:00
Matthias Kaehlcke b5b80f2b20 USB: ELAN U132 Host Controller Driver: convert sw_lock to mutex
The ELAN U132 Host Controller Driver uses the semaphore sw_lock as
mutex. Use the mutex API instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:24 -07:00
Alan Stern 4a00027dcb USB: Eliminate urb->status usage!
This patch (as979) removes the last vestiges of urb->status from the
host controller drivers and the root-hub emulator.  Now the field
doesn't get set until just before the URB's completion routine is
called.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
CC: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:23 -07:00
Alan Stern eb23105462 USB: add urb->unlinked field
This patch (as970) adds a new urb->unlinked field, which is used to
store the status of unlinked URBs since we can't use urb->status for
that purpose any more.  To help simplify the HCDs, usbcore will check
urb->unlinked before calling the completion handler; if the value is
set it will automatically override the status reported by the HCD.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
CC: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:19 -07:00
Alan Stern b0d9efba3e USB: centralize -EREMOTEIO handling
This patch (as969) continues the ongoing changes to the way HCDs
report URB statuses.  The programming interface has been simplified by
making usbcore responsible for clearing urb->hcpriv and for setting
-EREMOTEIO status when an URB with the URB_SHORT_NOT_OK flag ends up
as a short transfer.

By moving the work out of the HCDs, this removes a fair amount of
repeated code.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
CC: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:19 -07:00
Alan Stern e9df41c5c5 USB: make HCDs responsible for managing endpoint queues
This patch (as954) implements a suggestion of David Brownell's.  Now
the host controller drivers are responsible for linking and unlinking
URBs to/from their endpoint queues.  This eliminates the possiblity of
strange situations where usbcore thinks an URB is linked but the HCD
thinks it isn't.  It also means HCDs no longer have to check for URBs
being dequeued before they were fully enqueued.

In addition to the core changes, this requires changing every host
controller driver and the root-hub URB handler.  For the most part the
required changes are fairly small; drivers have to call
usb_hcd_link_urb_to_ep() in their urb_enqueue method,
usb_hcd_check_unlink_urb() in their urb_dequeue method, and
usb_hcd_unlink_urb_from_ep() before giving URBs back.  A few HCDs make
matters more complicated by the way they split up the flow of control.

In addition some method interfaces get changed.  The endpoint argument
for urb_enqueue is now redundant so it is removed.  The unlink status
is required by usb_hcd_check_unlink_urb(), so it has been added to
urb_dequeue.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Tony Olech <tony.olech@elandigitalsystems.com>
CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:10 -07:00
Jesper Juhl ca337db6f9 USB: Clean up duplicate includes in drivers/usb/
This patch cleans up duplicate includes in
	drivers/usb/

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:54:58 -07:00
Gabriel C 5b570d43ce USB: u132-hcd.c - Fix a warning when CONFIG_PM=n
I noticed this warning with CONFING_PM=n 

...

drivers/usb/host/u132-hcd.c:1525: warning: 'port_power' defined but not used

...

Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-22 14:27:44 -07:00
Matthias Kaehlcke d2066eb659 USB: use mutex instead of semaphore in the ELAN U132 adapter driver
The ELAN U132 adapter driver uses the semaphore u132_module_lock
as mutex. Use the mutex API instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-19 17:46:03 -07:00
David Brownell 47f8468e60 USB: fix more ftdi-elan/u132-hcd #include lossage
Partial fix for bogosity in the ftdi-elan and u132-hcd drivers ... these
have no business including with the internals of other drivers, much less
doing so in a broken way!!

A previous patch resolved one build fix, this resolves another...

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-22 23:45:48 -07:00
Randy Dunlap e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Tony Olech 4b87361d49 USB: u132-hcd/ftdi-elan: add support for Option GT 3G Quad card
ELAN's U132 is a USB to CardBus OHCI controller adapter,
    designed specifically for CardBus 3G data cards to
    function in machines without a CardBus slot.
The "ftdi-elan" module is a USB client driver, that detects
    a supported CardBus OHCI controller plugged into the
    U132 adapter and thereafter provides the conduit for
    for access by the "u132-hcd" module.
The "u132-hcd" module is a (cut-down OHCI) host controller
    that supports a single OHCI function of the CardBus 
    card inserted into the U132 adapter.

The problem with the initial implementation is that when
the CardBus card inserted into the U132 adapter has multiple
functions (and a CardBus card can support up to 4 functions),
it was the first function that was arbitrarily choosen.

The first batch of 3G cards tested, like the Merlin Qualcomm
V620, have two functions each supporting a seperate USB OHCI
host controller, of which it was that first function that is
wired up to the 3G modem.

Then along comes the Vodafone Mobile Connect 3G/GPRS data card,
aka "Option GT 3G Quad" as printed on it's rear or "Option N.V.
GlobeTrotter Fusion Quad Lite" as read with "lspci -v". And it
has the meaningful functionality in the second CardBus function.

That presents a problem because it was the "ftdi-elan" module
alone that knows how to communicate to the embedded CardBus slot
and the "u132-hcd" module alone that knows how to access the
pcmcia configuration and CardBus accessible memory space. And
of course, the information about attached (internally hardwired)
devices is contained within USB configuration embedded somewhere
within the CardBus card.

If only the "u132-hcd" module probe() interface could return a
result code that propagated back to the instigating function
platform_device_register() then the "ftdi-elan" module could
try an alternative CardBus function.     However in spite of
the recent changes to the drivers/base/ routines that moved 
device_attach() from bus_add_device() to bus_attach_device()
both of those routines lose the "failed to attach" 0 result
code and thus the calling routine, namely device_add() is
incapable of propaging the "failed to attach" condition back
to platform_device_add() and consequently back to the caller
of platform_device_register()

Experiments show that patching bus_attach_device() to return
ENODEV fails with the kernel locking up very early during
boot. But, however, if the patch is restricted to calls from
platform_device_add() then it does seem to work.

Unfortunately, until the kernel's drivers/base is properly
modified to propagate -ENODEV back to the caller of
platform_device_register(), it is necessary to "fix" the
"ftdi-elan" module by importing knowledge from the 
"u132-hcd" module. This is the reason for the duplicated
functionality introduced in this patch.

Signed-off-by: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 10:14:27 -08:00
David Howells 4c1ac1b491 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	drivers/infiniband/core/iwcm.c
	drivers/net/chelsio/cxgb2.c
	drivers/net/wireless/bcm43xx/bcm43xx_main.c
	drivers/net/wireless/prism54/islpci_eth.c
	drivers/usb/core/hub.h
	drivers/usb/input/hid-core.c
	net/core/netpoll.c

Fix up merge failures with Linus's head and fix new compilation failures.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 14:37:56 +00:00
Linus Torvalds 9641219825 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6: (103 commits)
  usbcore: remove unused argument in autosuspend
  USB: keep count of unsuspended children
  USB hub: simplify remote-wakeup handling
  USB: struct usb_device: change flag to bitflag
  OHCI: make autostop conditional on CONFIG_PM
  USB: Add autosuspend support to the hub driver
  EHCI: Fix root-hub and port suspend/resume problems
  USB: create a new thread for every USB device found during the probe sequence
  USB: add driver for the USB debug devices
  USB: added dynamic major number for USB endpoints
  USB: pegasus error path not resetting task's state
  USB: endianness fix for asix.c
  USB: build the appledisplay driver
  USB serial: replace kmalloc+memset with kzalloc
  USB: hid-core: canonical defines for Apple USB device IDs
  USB: idmouse cleanup
  USB: make drivers/usb/core/driver.c:usb_device_match() static
  USB: lh7a40x_udc remove double declaration
  USB: pxa2xx_udc recognizes ixp425 rev b0 chip
  usbtouchscreen: add support for DMC TSC-10/25 devices
  ...
2006-12-01 16:41:58 -08:00
Adrian Bunk 9ce8540c88 USB: ftdi-elan.c: fixes and cleanups
This patch contains the following possible cleanups:
- make the needlessly global ftdi_release_platform_dev() static
- remove the unused usb_ftdi_elan_read_reg()
- proper prototypes for the following functions:
  - usb_ftdi_elan_read_pcimem()
  - usb_ftdi_elan_write_pcimem()

Note that the misplaced prototypes for the latter ones in
drivers/usb/host/u132-hcd.c were buggy. Depending on the calling
convention of the architecture calling one of them could have turned
your stack into garbage.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:23:37 -08:00
Adrian Bunk 27a3de4cfc USB: make drivers/usb/host/u132-hcd.c:u132_hcd_wait static
This patch makes the needlessly global "u132_hcd_wait" static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:23:37 -08:00
Matt LaPlante 0779bf2d2e Fix misc .c/.h comment typos
Fix various .c/.h typos in comments (no code changes).

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 05:24:39 +01:00
David Howells c4028958b6 WorkStruct: make allyesconfig
Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:57:56 +00:00
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Dave Jones 038b0a6d8d Remove all inclusions of <linux/config.h>
kbuild explicitly includes this at build time.

Signed-off-by: Dave Jones <davej@redhat.com>
2006-10-04 03:38:54 -04:00
Tony Olech d774efeabc USB: u132-hcd: host controller driver for ELAN U132 adapter
This "u132-hcd" module is one half of the "driver" for
ELAN's U132 which is a USB to CardBus OHCI controller
adapter. This module needs the "ftdi-elan" module in
order to communicate to CardBus OHCI controller inserted
into the U132 adapter.

When the "ftdi-elan" module detects a supported CardBus
OHCI controller in the U132 adapter it loads this "u132-hcd"
module.

Upon a successful device probe() the single workqueue
is started up which does all the processing of commands
from the USB core that implement the host controller.

The workqueue maintains the urb queues and issues commands
via the functions exported by the "ftdi-elan" module. Each
such command will result in a callback.

Note that the "ftdi-elan" module is a USB client driver.

Note that this "u132-hcd" module is a (cut-down OHCI)
host controller.

Thus we have a topology with the parent of a host controller
being a USB client! This really stresses the USB subsystem
semaphore/mutex handling in the module removal.

Signed-off-by: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:58:59 -07:00