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
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accessibility
acpi	Merge branch 'x86-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-05-18 09:15:57 -07:00
amba
ata	pata_pcmcia / ide-cs: Fix bad hashes for Transcend and kingston IDs	2010-05-05 14:48:48 -04:00
atm
auxdisplay
base	Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6	2010-05-19 11:36:03 -07:00
block	Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-05-18 08:17:35 -07:00
bluetooth
cdrom
char	Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-05-18 08:35:04 -07:00
clocksource	Merge branch 'sh/stable-updates'	2010-04-26 16:08:27 +09:00
connector
cpufreq	Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-05-18 08:49:13 -07:00
cpuidle	cpuidle: Fix incorrect optimization	2010-05-09 18:35:36 -07:00
crypto
dca
dio
dma	Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6	2010-05-19 11:36:03 -07:00
edac	edac, mce: Fix wrong mask and macro usage	2010-04-30 10:15:39 -07:00
eisa
firewire	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6	2010-04-22 12:54:54 -07:00
firmware	Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip	2010-04-07 11:02:23 -07:00
gpio	it8761e_gpio: fix bug in gpio numbering	2010-05-11 17:33:41 -07:00
gpu	drivers/gpu/drm/i915/i915_irq.c:i915_error_object_create(): use correct kmap-atomic slot	2010-05-11 17:33:42 -07:00
hid	HID: fix suspend crash by moving initializations earlier	2010-05-07 23:33:52 +02:00
hwmon	Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging	2010-05-11 17:38:04 -07:00
i2c	i2c-s3c2410: Remove unconditional 1ms delay on each transfer	2010-05-20 00:18:58 +01:00
ide	pata_pcmcia / ide-cs: Fix bad hashes for Transcend and kingston IDs	2010-05-05 14:48:48 -04:00
idle
ieee1394
ieee802154
infiniband	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband	2010-04-09 11:53:06 -07:00
input	Merge branch 'for-linus/samsung4' of git://git.fluff.org/bjdooks/linux	2010-05-19 11:49:33 -07:00
isdn	Fix ISDN/Gigaset build failure	2010-04-19 11:53:17 -07:00
leds
lguest	lguest: stop using KVM hypercall mechanism	2010-04-14 21:43:56 +09:30
macintosh	device_attributes: add sysfs_attr_init() for dynamic attributes	2010-04-07 08:38:03 -07:00
mca
md	md: restore ability of spare drives to spin down.	2010-05-07 21:10:57 +10:00
media	V4L/DVB: pxa_camera: move fifo reset direct before dma start	2010-05-06 19:20:52 -03:00
memstick
message
mfd	mfd: Clean up after WM83xx AUXADC interrupt if it arrives late	2010-05-13 12:58:55 +02:00
misc	Modify the VMware balloon driver for the new x86_hyper API	2010-05-09 01:13:42 -07:00
mmc	Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm	2010-05-19 11:37:22 -07:00
mtd	[MTD] Remove zero-length files mtdbdi.c and internal.ho	2010-05-05 15:25:12 -04:00
net	m68k: amiga - Zorro bus modalias support	2010-05-17 21:37:41 +02:00
nubus
of	of: check for IS_ERR()	2010-04-28 01:07:29 -06:00
oprofile	oprofile: protect from not being in an IRQ context	2010-05-03 23:02:39 +02:00
parisc
parport
pci	Merge branch 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-05-18 07:22:37 -07:00
pcmcia	[ARM] pxa: add support for Voipac PXA270 PCMCIA	2010-05-11 17:25:02 +02:00
platform	eeepc-laptop: add missing sparse_keymap_free	2010-04-23 15:23:21 -04:00
pnp	Merge branches 'bugzilla-14337', 'bugzilla-14998', 'bugzilla-15407', 'bugzilla-15903' and 'misc-2.6.34' into release	2010-05-06 22:04:31 -04:00
power
pps
ps3
rapidio
regulator	regulator: fix enabling regulator issue on max8925	2010-04-28 15:24:34 +01:00
rtc	Revert "rtc: omap: let device wakeup capability be configured from chip init logic"	2010-05-19 11:37:20 -07:00
s390	[S390] drivers/s390/char: Use kmemdup	2010-05-17 10:00:18 +02:00
sbus
scsi	m68k: amiga - Zorro bus modalias support	2010-05-17 21:37:41 +02:00
serial	Merge branch 'for-linus/samsung4' of git://git.fluff.org/bjdooks/linux	2010-05-19 11:49:33 -07:00
sfi
sh	sh: simplify WARN usage in SH clock driver	2010-05-13 17:43:11 +09:00
sn
spi	[ARM] pxa: add namespace on ssp	2010-05-11 17:25:06 +02:00
ssb	MIPS: Fix SSB PCIcore IO resource management	2010-04-12 17:26:14 +01:00
staging	Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus	2010-04-30 13:04:14 -07:00
tc
telephony
thermal	drivers/thermal/thermal_sys.c: fix 'key f70f4b50 not in .data' in thermal_sys	2010-04-07 08:38:03 -07:00
uio
usb	Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm	2010-05-19 11:37:22 -07:00
uwb
vhost	vhost: fix barrier pairing	2010-05-12 18:04:04 +03:00
video	m68k: amiga - Frame buffer platform device conversion	2010-05-17 21:37:43 +02:00
virtio	virtio: Fix GFP flags passed from the virtio balloon driver	2010-04-22 07:34:05 -07:00
vlynq
w1	w1: fix omap 1-wire driver compilation	2010-04-24 11:31:25 -07:00
watchdog	ARM: 6126/1: ARM mpcore_wdt: fix build failure and other fixes	2010-05-12 11:18:14 +01:00
xen	stop_machine: reimplement using cpu_stop	2010-05-06 18:49:20 +02:00
zorro	m68k: amiga - Zorro host bridge platform device conversion	2010-05-17 21:37:42 +02:00
Kconfig
Makefile	virtio: initialize earlier	2010-05-07 14:01:17 -07:00