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2008-07-20mfd: let asic3 use mem resource instead of bus_shiftPhilipp Zabel1-6/+5
The bus_shift parameter in platform_data is not needed as we can tell the driver with the IOMEM_RESOURCE whether the ASIC is located on a 16bit or 32bit memory bus. The htc-egpio driver uses a more descriptive bus_width parameter, but for drivers where the register map size fixed, we don't even need this. Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-07-20mfd: fix the asic3 irq demux codePhilipp Zabel1-1/+1
Wrong irq numbers were given to desc->handle_irq, which on some devices caused endless loops (asic3_irq_demux calling itself, basically). Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: asic3 should depend on gpiolibSamuel Ortiz1-1/+1
Now that asic3 implements the gpiolib API, it should depend on it at build time. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: fix asic3 config array initialisationPhilipp Zabel1-3/+3
Our memset length was incorrect. Tested-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: move asic3 probe functions into __init sectionPhilipp Zabel1-6/+5
Potentially free some memory by moving the _probe functions into __init. Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: Use uppercase only for asic3 macros and definesSamuel Ortiz1-44/+44
Let's be consistent and use uppercase only, for both macro and defines. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: use dev_* macros for asic3 debuggingSamuel Ortiz1-14/+13
We replace the various printks, and use the dev_* macros instead. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: New asic3 gpio configuration codeSamuel Ortiz1-56/+43
The ASIC3 GPIO configuration code is a bit obscure and hardly readable. This patch changes it so that it is now more readable and understandable, by being more explicit. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: asic3 children platform data removalSamuel Ortiz1-8/+0
Platform devices should be dynamically allocated, and each supported device should have its own platform data. For now we just remove this buggy code. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-07-20mfd: asic3 gpiolib supportSamuel Ortiz1-71/+153
ASIC3 is, among other things, a GPIO extender. We should thus have it supporting the current gpiolib API. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-05-21HTC_EGPIO is ARM-onlyAl Viro1-1/+1
driver uses symbols defined only on ARM Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30drivers: replace remaining __FUNCTION__ occurrencesHarvey Harrison2-5/+5
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29Merge master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds1-4/+5
* master.kernel.org:/home/rmk/linux-2.6-arm: (26 commits) [ARM] pxa: fix 1c104e0e4f6ab396960c058e95e18bdedcac945b [ARM] serial: s3c2410: platform_get_irq() may return signed unnoticed [ARM] am79c961a: platform_get_irq() may return signed unnoticed [ARM] Feroceon: Feroceon-specific WA-cache compatible {copy,clear}_user_page() [ARM] Feroceon: fix function alignment in proc-feroceon.S [ARM] Orion: catch a couple more alternative spellings of PCIe [ARM] Orion: fix orion-ehci platform resource end addresses [ARM] Orion: fix ->map_irq() PCIe bus number check [ARM] Orion: fix ioremap() optimization [ARM] feroceon: remove CONFIG_CPU_CACHE_ROUND_ROBIN check [ARM] feroceon: remove CONFIG_CPU_DCACHE_WRITETHROUGH check kprobes/arm: fix decoding of arithmetic immediate instructions kprobes/arm: fix cache flush address for instruction stub [ARM] 5022/1: Race in ARM MMCI PL18x driver, V2 [ARM] 5021/1: at91: buildfix for sam9263 + PM [ARM] 5018/1: RealView: Fix the ARM11MPCore Oprofile compilation [ARM] 5016/1: AT91: typo in mci configuration for at91cap at91sam9263 [ARM] 5017/1: pxa3xx: Report unsupported wakeup sources in pxa3xx_set_wake() [ARM] 5020/1: magician: remove __devinit marker from pasic3_leds_info [ARM] 5014/1: Cleanup reset state before entering suspend or resetting. ...
2008-04-29Merge branches 'pxa' and 'orion-fixes1'Russell King1-4/+5
2008-04-28mfd: use shorter set_current_state()Robert P. J. Day1-4/+3
Since this routine declares a separate "tsk" pointer for no other reason than to call set_task_state(), get rid of it and just invoke set_current_state(). Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Dmitry Torokhov <dtor@mail.ru> Cc: Nicolas Pitre <nico@cam.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28sm501: add uart supportMagnus Damm1-16/+68
This patch extends the sm501 mfd with 8250 uart support. We're currently doing this in the board specific r2d-1 code already, but it would be nice to do move things into the mfd since it's more chip specific than board specific. Signed-off-by: Magnus Damm <damm@igel.co.jp> Cc: Ben Dooks <ben-linux@fluff.org> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-24Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds1-3/+0
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm: [ARM] fix 48d7927bdf071d05cf5d15b816cf06b0937cb84f [ARM] 5010/1: htc-pasic3: remove unused defines and includes [ARM] pxa: fix 0e623941bec7e80c97b076d346327b31ae17d84a [ARM] fix lh7a40x/kev7a400 build
2008-04-24[ARM] 5011/1: htc-pasic3: fix bug in resource pipe-through to ds1wmPhilipp Zabel1-4/+5
The newly created DS1WM platform device should get a copy of the PASIC3 platform devices' resources. Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-04-24[ARM] 5010/1: htc-pasic3: remove unused defines and includesPhilipp Zabel1-3/+0
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-04-21Merge branch 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/miscLinus Torvalds1-1/+0
* 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: Deprecate the asm/semaphore.h files in feature-removal-schedule. Convert asm/semaphore.h users to linux/semaphore.h security: Remove unnecessary inclusions of asm/semaphore.h lib: Remove unnecessary inclusions of asm/semaphore.h kernel: Remove unnecessary inclusions of asm/semaphore.h include: Remove unnecessary inclusions of asm/semaphore.h fs: Remove unnecessary inclusions of asm/semaphore.h drivers: Remove unnecessary inclusions of asm/semaphore.h net: Remove unnecessary inclusions of asm/semaphore.h arch: Remove unnecessary inclusions of asm/semaphore.h
2008-04-19Merge branch 'omap2-upstream' into develRussell King1-2/+2
2008-04-19[ARM] 4964/1: htc-pasic3: MFD driver for PASIC3 LED control + DS1WM chipPhilipp Zabel3-0/+274
This driver will provide registers, clocks and GPIOs of the HTC PASIC3 (AIC3) and PASIC2 (AIC2) chips to the ds1wm and leds-pasic3 drivers. Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-04-19[ARM] 4947/1: htc-egpio, a driver for GPIO/IRQ expanders with fixed input/output pinsPhilipp Zabel3-0/+450
implemented in CPLD chips on several HTC devices. The original driver was written by Kevin O'Connor, I have adapted it to use gpiolib and made the bus/register widths configurable. Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-04-18drivers: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox1-1/+0
None of these files use any of the functionality promised by asm/semaphore.h. It's possible that they rely on it dragging in some unrelated header file, but I can't build all these files, so we'll have fix any build failures as they come up. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-03-30mfd/asic3: ioread/iowrite take pointer, not unsigned longAl Viro1-2/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-04sm501: add support for the SM502 programmable PLLVille Syrjala1-35/+128
SM502 has a programmable PLL which can provide the panel pixel clock instead of the 288MHz and 336MHz PLLs. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Ville Syrjala <syrjala@sci.fi> Cc: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-04sm501: remove a duplicated tableVille Syrjala1-32/+13
misc_div is a subset of px_div so eliminate the smaller table. Signed-off-by: Ville Syrjala <syrjala@sci.fi> Cc: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07ASIC3 driverSamuel Ortiz3-0/+596
This is a patch for the Compaq ASIC3 multi function chip, found in many PDAs (iPAQs, HTCs...). It is a simplified version of Paul Sokolovsky's first proposal [1]. With this code, it is basically a GPIO and IRQ expander. My plan is to add more features once this patch gets reviewed and accepted. [1] http://lkml.org/lkml/2007/5/1/46 Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Cc: Paul Sokolovsky <pmiscml@gmail.com> Cc: Ben Dooks <ben@trinity.fluff.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-28[ARM] Fix class_device damage caused by 0c55445f201841bfd6c658c47df8311b6722f002Russell King1-7/+7
Lots of compile errors in drivers/mfd/ucb1x00-assabet.c... Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-01-24MCP_UCB1200: Convert from class_device to deviceTony Jones3-17/+18
struct class_device is going away, this converts the code to use struct device instead. Signed-off-by: Tony Jones <tonyj@suse.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-29MFD: SM501 debug typo fixBen Dooks1-1/+1
Remove errnoeous x character from dev_dbg() call that stops the driver compiling under debug. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-20typo fixesMatt LaPlante1-2/+2
Most of these fixes were already submitted for old kernel versions, and were approved, but for some reason they never made it into the releases. Because this is a consolidation of a couple old missed patches, it touches both Kconfigs and documentation texts. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-07-19some kmalloc/memset ->kzalloc (tree wide)Yoann Padioleau2-4/+2
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: Yoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Acked-by: Pierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Greg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17Freezer: make kernel threads nonfreezable by defaultRafael J. Wysocki1-0/+1
Currently, the freezer treats all tasks as freezable, except for the kernel threads that explicitly set the PF_NOFREEZE flag for themselves. This approach is problematic, since it requires every kernel thread to either set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't care for the freezing of tasks at all. It seems better to only require the kernel threads that want to or need to be frozen to use some freezer-related code and to remove any freezer-related code from the other (nonfreezable) kernel threads, which is done in this patch. The patch causes all kernel threads to be nonfreezable by default (ie. to have PF_NOFREEZE set by default) and introduces the set_freezable() function that should be called by the freezable kernel threads in order to unset PF_NOFREEZE. It also makes all of the currently freezable kernel threads call set_freezable(), so it shouldn't cause any (intentional) change of behaviour to appear. Additionally, it updates documentation to describe the freezing of tasks more accurately. [akpm@linux-foundation.org: build fixes] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: Pavel Machek <pavel@ucw.cz> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24SM501: Check SM501 ID register on initialisationBen Dooks1-4/+10
When binding the driver, check the ID register for a valid identity, in case the SM501 is not functioning correctly. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24SM501: Clock updates and checksBen Dooks1-2/+31
Ensure that the M1XCLK and MCLK are sourced from the same PLL (and refuse to bind the driver if they are not). Update the PCI to safe initialisation values, as 72MHz is the maximum clock for 33MHz PCI bus mastering. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24SM501: Fix sm501_init_reg() mask/set orderBen Dooks1-1/+4
The order of the set and mask operation in sm501_init_reg() was setting and then masking the bits set. Correct the order so that we do not end up with 288MHz SDRAM clocks on certain systems. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24SM501: initialise SDRAM clock before bus clocksBen Dooks1-5/+5
This init sequence of setting the SDRAM clock before the bus clock is recommend by Silicon Motion to stop problems with writes not sticking into registers. Signed-off-by: Vincent Sanders <vince@simtec.co.uk> Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24SM501: suspend supportBen Dooks1-8/+105
This patch adds support for suspending the core (mfd driver) of the SM501. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-04Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds1-3/+4
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: reduce raciness when input handlers disconnect Input: ucb1x00 - do not access input_dev->private directly Input: logips2pp - fix typo in Kconfig Input: db9 - do not ignore dev2 module parameter
2007-06-03Input: ucb1x00 - do not access input_dev->private directlyDmitry Torokhov1-3/+4
Use input_get_drvdata() and input_set_drvdata() helpers to do that. Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Acked-by: Pavel Machek <pavel@ucw.cz>
2007-05-23Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds1-10/+1
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: ads7846 - SPI_CPHA mode bugfix Input: ads7846 - document that it handles tsc2046 too Input: input-polldev - add module info Input: ucb1x00-ts - remove commented out code Input: ucb1400_ts - use sched_setscheduler() Input: ALPS - force stream mode Input: iforce - minor clean-ups Input: iforce - fix force feedback not working Input: adbhid - do not access input_dev->private directly Input: logips2pp - add type 72 (PS/2 TrackMan Marble)
2007-05-22Input: ucb1x00-ts - remove commented out codeDmitry Torokhov1-10/+1
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2007-05-10[S390] Kconfig: menus with depends on HAS_IOMEM.Martin Schwidefsky1-0/+1
Add "depends on HAS_IOMEM" to a number of menus to make them disappear for s390 which does not have I/O memory. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap1-1/+0
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>
2007-04-02[PATCH] drivers/mfd/sm501.c: fix an off-by-oneAdrian Bunk1-1/+1
Fix an off-by-one spotted by the Coverity checker. Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Ben Dooks <ben-linux@fluff.org> Cc: Vincent Sanders <vince@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-26[PATCH] drivers/mfd/sm501.c: Replace pci_module_init with pci_register_driverRichard Knutsson1-1/+1
Replace pci_module_init with pci_register_driver Signed-off-by: Richard Knutson <ricknu-0@student.ltu.se> Acked-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-20[PATCH] mfd: SM501 core driverBen Dooks3-0/+1164
This driver provides the core functionality of the SM501, which is a multi-function chip including two framebuffers, video acceleration, USB, and many other peripheral blocks. The driver exports a number of entries for the peripheral drivers to use. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Vincent Sanders <vince@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-07[PATCH] Add include/linux/freezer.h and move definitions from sched.hNigel Cunningham1-1/+1
Move process freezing functions from include/linux/sched.h to freezer.h, so that modifications to the freezer or the kernel configuration don't require recompiling just about everything. [akpm@osdl.org: fix ueagle driver] Signed-off-by: Nigel Cunningham <nigel@suspend2.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-05IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells1-1/+1
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)
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