Commit Graph

56 Commits

Author SHA1 Message Date
H Hartley Sweeten 2178218027 i2c: Use <linux/io.h> instead of <asm/io.h>
As warned by checkpatch.pl, <linux/io.h> should be used instead of
<asm/io.h>.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:41:01 +02:00
Mark Brown 1bc2962e53 i2c-s3c2410: Remove unconditional 1ms delay on each transfer
The S3C I2C controller indicates completion of I2C transfers before
the bus has a stop condition on it. In order to ensure that we do not
attempt to start a new transfer before the bus is idle the driver
currently inserts a 1ms delay. This is vastly larger than is generally
required and has a visible effect on performance under load, such as
when bringing up audio CODECs or reading back status information with
non-bulk I2C reads.

Replace the sleep with a spin on the IIC status register for up to 1ms.
This will busy wait but testing on my SMDK6410 system indicates that
the overwhelming majority of transactions complete on the first spin,
with maximum latencies of less than 10 spins so the absolute overhead
of busy waiting should be at worst comprable to msleep(), and the
overall system performance is dramatically improved.

The main risk is poor interaction with multimaster systems where
we may miss the bus going idle before the next transaction. Defend
against this by falling back to the original 1ms delay after 20 spins.

The overall effect in my testing is an approximately 20% improvement
in kernel startup time.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 00:18:58 +01:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Alexey Dobriyan 471452104b const: constify remaining dev_pm_ops
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:25 -08:00
Rafael J. Wysocki 2e6713c766 Merge branch 'master' into for-linus 2009-07-30 19:38:04 +02:00
Peter Korsgaard 0e014e92ba i2c-s3c2410: s3c24xx_i2c_init: don't clobber IICLC value
s3c24xx_i2c_init() was overwriting the IICLC value set just above in
s3c24xx_i2c_clockrate() with zero, effectively disabling the platform
line control setting.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-07-30 00:55:50 +01:00
Magnus Damm 6a6c6189b1 I2C: Rework i2c-s3c2410 suspend_late()/resume() V2
This is V2 of the i2c-s3c2410 dev_pm_ops patch.

The callbacks are converted for CONFIG_SUSPEND like this:
  suspend_late() -> suspend_noirq()
  resume() -> resume()

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-07-22 00:28:39 +02:00
Ben Dooks 933a2aec8d i2c-s3c2410: use resource_size()
Change the usage of res->end-res->start to resource_size(), missed
by the last patch to change this.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-16 22:42:16 +01:00
Ben Dooks 7d85ccd816 i2c-s3c2410: move to using platform idtable to match devices
Change to using platform id table to match either of the two supported
platform device names in the driver. This simplifies the driver init and
exit code

Note, log messages will now be prefixed with 's3c-i2c' instead of the
driver name, so output will be of the form of:

s3c-i2c s3c2440-i2c.0: slave address 0x10

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-13 10:39:26 +01:00
Mark Brown 18dc83a6ea i2c: i2c-s3c2410: Initialise Samsung I2C controller early
This is required in order to ensure that core system devices such as
voltage regulators attached via I2C are avaiable early in boot.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-04-07 10:18:33 +01:00
Daniel Silverstone c564e6ae6c i2c-s3c2410: Simplify bus frequency calculation
The platform data for the i2c-s3c2410 driver used to allow a min,
max and desired frequency for the I2C bus. This patch reduces it
to simply a desired frequency ceiling and corrects all the uses
of the platform data appropriately.

This means, for example, that on a system with a 66MHz fclk, a
request for 100KHz will achieve 65KHz which is safe and
acceptable, rather than 378KHz which it would have achieved
without this change.

Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Signed-off-by: Daniel Silverstone <dsilvers@simtec.co.uk>
[ben-linux@fluff.org: tidy subject and description]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-04-07 10:18:33 +01:00
Ben Dooks a192f7153b i2c-s3c2410: sda_delay should be in ns, not clock ticks
The sda_delay field should be specified in ns, not in clock ticks
as when using cpufreq we could be changing the bus rate.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
2009-04-07 10:18:33 +01:00
Jean Delvare 22e965c2ae i2c: Get rid of remaining bus_id access
Use dev_name(dev) instead of accessing dev.bus_id directly, as the
latter is going away soon.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
2009-01-07 14:29:16 +01:00
Linus Torvalds c58bd34d00 Merge branch 'i2c-next' of git://aeryn.fluff.org.uk/bjdooks/linux
* 'i2c-next' of git://aeryn.fluff.org.uk/bjdooks/linux:
  i2c-omap: fix type of irq handler function
  i2c-s3c2410: Change IRQ to be plain integer.
  i2c-s3c2410: Allow more than one i2c-s3c2410 adapter
  i2c-s3c2410: Remove default platform data.
  i2c-s3c2410: Use platform data for gpio configuration
  i2c-s3c2410: Fixup style problems from checkpatch.pl
  i2c-omap: Enable I2C wakeups for 34xx
  i2c-omap: reprogram OCP_SYSCONFIG register after reset
  i2c-omap: convert 'rev1' flag to generic 'rev' u8
  i2c-omap: fix I2C timeouts due to recursive omap_i2c_{un,}idle()
  i2c-omap: Clean-up i2c-omap
  i2c-omap: Don't compile in OMAP15xx I2C ISR for non-OMAP15xx builds
  i2c-omap: Mark init-only functions as __init
  i2c-omap: Add support for omap34xx
  i2c-omap: FIFO handling support and broken hw workaround for i2c-omap
  i2c-omap: Add high-speed support to omap-i2c
  i2c-omap: Close suspected race between omap_i2c_idle() and omap_i2c_isr()
  i2c-omap: Do not use interruptible wait call in omap_i2c_xfer_msg

Fix up apparently-trivial conflict in drivers/i2c/busses/i2c-s3c2410.c
2009-01-05 18:58:06 -08:00
Linus Torvalds 14a3c4ab0e Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (407 commits)
  [ARM] pxafb: add support for overlay1 and overlay2 as framebuffer devices
  [ARM] pxafb: cleanup of the timing checking code
  [ARM] pxafb: cleanup of the color format manipulation code
  [ARM] pxafb: add palette format support for LCCR4_PAL_FOR_3
  [ARM] pxafb: add support for FBIOPAN_DISPLAY by dma braching
  [ARM] pxafb: allow pxafb_set_par() to start from arbitrary yoffset
  [ARM] pxafb: allow video memory size to be configurable
  [ARM] pxa: add document on the MFP design and how to use it
  [ARM] sa1100_wdt: don't assume CLOCK_TICK_RATE to be a constant
  [ARM] rtc-sa1100: don't assume CLOCK_TICK_RATE to be a constant
  [ARM] pxa/tavorevb: update board support (smartpanel LCD + keypad)
  [ARM] pxa: Update eseries defconfig
  [ARM] 5352/1: add w90p910-plat config file
  [ARM] s3c: S3C options should depend on PLAT_S3C
  [ARM] mv78xx0: implement GPIO and GPIO interrupt support
  [ARM] Kirkwood: implement GPIO and GPIO interrupt support
  [ARM] Orion: share GPIO IRQ handling code
  [ARM] Orion: share GPIO handling code
  [ARM] s3c: define __io using the typesafe version
  [ARM] S3C64XX: Ensure CPU_V6 is selected
  ...
2008-12-30 17:36:49 -08:00
Ben Dooks e0d1ec9785 i2c-s3c2410: Change IRQ to be plain integer.
Change the code to use a plain integer as the holder
for the IRQ for the device and use platform_get_irq()
to find it.

This makes the code slightly neater, and easier to get
the IRQ number.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:27:28 +00:00
Ben Dooks 692acbd3a8 i2c-s3c2410: Allow more than one i2c-s3c2410 adapter
Newer SoCs such as the S3C6410 have 2 instances of this i2c
controller block in and thus require the ability to create
two seperate busses from this.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:26:46 +00:00
Ben Dooks 6a039cabba i2c-s3c2410: Remove default platform data.
The platform data should now always be present when the device
is initialised, so we can remove the default platform data in
the driver.

All the device initialisation points in the board specific code
should already have been changed to initialise this as necessary.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:26:06 +00:00
Ben Dooks 8be310a6de i2c-s3c2410: Use platform data for gpio configuration
Add a callback to set the gpio configuration for the
i2c device instead of a set include. This also allows
the remvoal of the machine gpio and hardware files.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:25:53 +00:00
Ben Dooks 3d0911bfe0 i2c-s3c2410: Fixup style problems from checkpatch.pl
Fixup the 36 warnings and errors generated from running
checkpatch.pl on the driver. The warnings are too numerous
to be listed here.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:24:16 +00:00
Ben Dooks be44f01e8a i2c-s3c2410: fix check for being in suspend.
As noted by Julia Lawall <julia@diku.dk>, we can never
trigger the check for being in suspend due to the result
of !readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN
always being 0.

Add suspend/resume hooks to stop i2c transactions happening
until the driver has been resumed.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:19:53 +00:00
Ben Dooks e856359685 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into s3c-moves2 2008-11-03 14:49:01 +00:00
Julia Lawall da6801e38b i2c-s3c2410: Correct use of ! and &
In commit e6bafba5b4, a bug was fixed that
involved converting !x & y to !(x & y).  The code below shows the same
pattern, and thus should perhaps be fixed in the same way.  In particular,
the result of !readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN is
always 0.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@ expression E; constant C; @@
(
  !E & !C
|
- !E & C
+ !(E & C)
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-30 15:55:47 +01:00
Ben Dooks 9498cb7946 [ARM] S3C: Move i2c headers to arch/arm/plat-s3c/include/plat.
Move the i2c headers to arch/arm/plat-s3c/include/plat
ready to clean out the old include directories.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-10-30 10:17:12 +00:00
Russell King a09e64fbc0 [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach
This just leaves include/asm-arm/plat-* to deal with.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07 09:55:48 +01:00
Russell King 4fb8af10d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes 2008-08-07 09:55:03 +01:00
Russell King be50972935 [ARM] Remove asm/hardware.h, use asm/arch/hardware.h instead
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h.
Then, since asm/hardware.h only exists to include asm/arch/hardware.h,
update everything to directly include asm/arch/hardware.h and remove
asm/hardware.h.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07 09:40:08 +01:00
Ben Dooks 61c7cff892 i2c: S3C24XX I2C frequency scaling support.
Add support for CPU frequency scaling to the S3C24XX I2C driver.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-28 12:41:01 +01:00
Ben Dooks 399dee2371 i2c: S3C2410: Pass the I2C bus number via drivers platform data
Allow the platform data to specify the bus bumber that the
new I2C bus will be given. This is to allow the use of the
board registration mechanism to specify the new style of
I2C device registration which allows boards to provide a
list of attached devices.

Note, as discussed on the mailing list, we have dropped
backwards compatibility of adding an dynamic bus number
as it should not affect most boards to have the bus pinned
to 0 if they have either not specified platform data for
driver. Any board supplying platform data will automatically
have the bus_num field set to 0, and anyone who needs the
driver on a different bus number can supply platform data
to set bus_num.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-28 12:05:26 +01:00
Jean Delvare 3401b2fff3 i2c: Let bus drivers add SPD to their class
Let general purpose I2C/SMBus bus drivers add SPD to their class. Once
this is done, we will be able to tell the eeprom driver to only probe
for SPD EEPROMs and similar on these buses.

Note that I took a conservative approach here, adding I2C_CLASS_SPD to
many drivers that have no idea whether they can host SPD EEPROMs or not.
This is to make sure that the eeprom driver doesn't stop probing buses
where SPD EEPROMs or equivalent live.

So, bus driver maintainers and users should feel free to remove the SPD
class from drivers those buses never have SPD EEPROMs or they don't
want the eeprom driver to bind to them. Likewise, feel free to add the
SPD class to any bus driver I might have missed.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14 22:38:29 +02:00
Ben Dooks d150a4bbd0 I2C: S3C2410: Add MODULE_ALIAS() for s3c2440 device.
Add a MODULE_ALIAS() statement for the i2c-s3c2410 controller
to ensure that it can be autoloaded on the S3C2440 systems that
we support.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-01 14:30:38 +01:00
Ben Dooks 63f5c2891e I2C: S3C2410: Fixup error codes returned rom a transfer.
The driver should be returning -ENXIO for transfers that do not
pass the initial address byte stage.

Note, also small tidyups to the driver comments in the area.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-01 14:30:37 +01:00
Ben Dooks 2709781be6 I2C: S3C2410: Check ACK on byte transmission
We should check for the reception of an ACK after transmitting each
data byte. The address send has been correctly checking this, but the
data write byte state should have also been checking for these failures.

As part of the same fix, we remove the ACK checking from the receive
path where it should not have been checking for an ACK which our hardware
was sending.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-01 14:30:37 +01:00
Kay Sievers add8eda7f2 i2c: Fix platform driver hotplug/coldplug
Since 43cc71eed1, the platform
modalias is prefixed with "platform:". Add MODULE_ALIAS() to the
hotpluggable I2C platform drivers, to allow module auto loading.

[ db: add some more drivers ]

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:49 +02:00
Harvey Harrison 08882d2093 i2c: Replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:47 +02:00
Ben Dooks b5d0b4ba38 i2c-s3c2410: Build fix
Fixup the include files after the arch moves that
where included in 2.6.23.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-08-14 18:37:15 +02:00
Arnaud Patard a1ba15832c i2c-s3c2410: Fix build warning
Fix for the following build warning:
  CC      drivers/i2c/busses/i2c-s3c2410.o
  drivers/i2c/busses/i2c-s3c2410.c: In function 's3c24xx_i2c_probe':
  drivers/i2c/busses/i2c-s3c2410.c:839: warning: format '%ld' expects type 'long int', but argument 4 has type 'resource_size_t'

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-22 19:49:16 +02:00
Ben Dooks 5b68790cd5 i2c-s3c2410: Fix bug in releasing driver
When compiled as a module, the i2c-s3c2410 driver does not
free either the IRQ or the i2c adapter it attached to the system.

As part of this fix, move to the usual kernel style
of freeing items as part of the probe error path
making the remove process easier.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 23:26:35 +02:00
Ben Dooks e00a8cdf32 i2c-s3c2410: Fix I2C SDA to SCL setup time
Fix the setup time for SDA to SCL due to the way
the S3C24XX I2C controller works.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 23:26:35 +02:00
Milind Arun Choudhary 35532d2003 i2c: SPIN_LOCK_UNLOCKED cleanup
SPIN_LOCK_UNLOCKED cleanup, use __SPIN_LOCK_UNLOCKED instead.

Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 23:26:34 +02:00
Tim Schmielau cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00
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
Jean Delvare 8f9082c5ce i2c: Constify i2c_algorithm declarations, part 2
i2c: Constify i2c_algorithm declarations, part 2

Make struct i2c_algorithm declarations const in all i2c bus drivers
where it is possible.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-26 15:38:52 -07:00
Thomas Gleixner dace145374 [PATCH] irq-flags: misc drivers: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:50 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Russell King f8ce25476d [ARM] Move asm/hardware/clock.h to linux/clk.h
This is needs to be visible to other architectures using the AMBA
bus and peripherals.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-07 16:15:52 +00:00
Russell King a8d3584a2d [ARM] Remove clk_use()/clk_unuse()
It seems that clk_use() and clk_unuse() are additional complexity
which isn't required anymore.  Remove them from the clock framework
to avoid the additional confusion which they cause, and update all
ARM machine types except for OMAP.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-03 18:41:37 +00:00
Russell King 3ae5eaec1d [DRIVER MODEL] Convert platform drivers to use struct platform_driver
This allows us to eliminate the casts in the drivers, and eventually
remove the use of the device_driver function pointer methods for
platform device drivers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-09 22:32:44 +00:00
Russell King e32e28edc3 [DRIVER MODEL] Add missing driver_unregister in i2c-s3c2410 failure path.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-30 16:32:27 +00:00
Russell King d052d1beff Create platform_device.h to contain all the platform device details.
Convert everyone who uses platform_bus_type to include
linux/platform_device.h.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-29 19:07:23 +01:00