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linux-sg2042/drivers
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Daniel Vetter 28c70f162a drm/i915: use the gmbus irq for waits 
We need two special things to properly wire this up:
- Add another argument to gmbus_wait_hw_status to pass in the
  correct interrupt bit in gmbus4.
- Since we can only get an irq for one of the two events we want,
  hand-roll the wait_event_timeout code so that we wake up every
  jiffie and can check for NAKs. This way we also subsume gmbus
  support for platforms without interrupts (or where those are not
  yet enabled).

The important bit really is to only enable one gmbus interrupt source
at the same time - with that piece of lore figured out, this seems to
work flawlessly.

Ben Widawsky rightfully complained the lack of measurements for the
claimed benefits (especially since the first version was actually
broken and fell back to bit-banging). Previously reading the 256 byte
hdmi EDID takes about 72 ms here. With this patch it's down to 33 ms.
Given that transfering the 256 bytes over i2c at wire speed takes
20.5ms alone, the reduction in additional overhead is rather nice.

v2: Chris Wilson wondered whether GMBUS4 might contain some set bits
when booting up an hence result in some spurious interrupts. Since we
clear GMBUS4 after every wait and we do gmbus transfer really early in
the setup sequence to detect displays the window is small, but still
be paranoid and clear it properly.

v3: Clarify the comment that gmbus irq generation can only support one
kind of event, why it bothers us and how we work around that limit.

Cc: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
 		2012-12-06 13:14:37 +01:00
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accessibility
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acpi ACPI video: Ignore errors after _DOD evaluation. 2012-11-03 09:52:54 +08:00
amba
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ata Merge branch 'samsung_platform_data' into staging/for_v3.7 2012-10-05 22:32:05 -03:00
atm sections: fix section conflicts in drivers/atm 2012-10-06 03:04:40 +09:00
auxdisplay
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base Power management and ACPI fixes for 3.7-rc3 2012-10-26 14:23:35 -07:00
bcma bcma: fix unregistration of cores 2012-10-15 14:45:51 -04:00
block loop: Make explicit loop device destruction lazy 2012-10-30 08:37:31 +01:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-10-02 13:38:27 -07:00
bus drivers: bus: omap_l3: fixup merge conflict resolution 2012-10-01 19:39:48 -07:00
cdrom
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char Merge branch 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2012-11-20 09:22:35 +10:00
clk spi: Updates for v3.7 2012-10-02 17:26:42 -07:00
clocksource Power management updates for 3.7-rc1 2012-10-02 18:32:35 -07:00
connector Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-10-02 13:38:27 -07:00
cpufreq cpufreq / powernow-k8: Change maintainer's email address 2012-10-31 21:02:57 +01:00
cpuidle ACPI idle, CPU hotplug: Fix NULL pointer dereference during hotplug 2012-10-08 22:52:54 -04:00
crypto ARM: soc: late platform updates 2012-10-07 20:55:16 +09:00
dca
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devfreq
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dio
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dma Merge branch 'fixes' of git://git.infradead.org/users/vkoul/slave-dma 2012-10-26 14:59:01 -07:00
edac amd64_edac:__amd64_set_scrub_rate(): avoid overindexing scrubrates[] 2012-10-24 16:13:27 +02:00
eisa
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extcon extcon : register for cable interest by cable name 2012-10-23 16:32:18 +09:00
firewire firewire: cdev: fix user memory corruption (i386 userland on amd64 kernel) 2012-10-09 18:26:28 +02:00
firmware firmware/memmap: avoid type conflicts with the generic memmap_init() 2012-10-19 14:07:47 -07:00
gpio Some GPIO fixes for the v3.7 series since -rc1: 2012-10-30 15:56:22 -07:00
gpu drm/i915: use the gmbus irq for waits 2012-12-06 13:14:37 +01:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid 2012-10-31 15:39:28 -07:00
hsi
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hv Drivers: hv: Cleanup error handling in vmbus_open() 2012-10-24 15:46:27 -07:00
hwmon hwmon: Only include of_match_table with CONFIG_OF_GPIO 2012-11-01 17:31:20 -07:00
hwspinlock
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i2c Merge branch 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux 2012-11-03 15:14:54 -07:00
ide sections: fix section conflicts in drivers/ide 2012-10-06 03:04:41 +09:00
idle intel_idle: enable IVB Xeon support 2012-09-26 22:28:21 -04:00
iio iio: Remove duplicates for light/ in Kconfig and Makefile 2012-10-19 19:44:06 +01:00
infiniband Merge branches 'cxgb4' and 'mlx4' into for-next 2012-10-23 09:03:49 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2012-11-02 16:11:15 -07:00
iommu iommu/tegra: smmu: Fix deadly typo 2012-10-24 16:58:53 +02:00
irqchip
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isdn bas_gigaset: fix pre_reset handling 2012-10-26 02:20:36 -04:00
leds Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2012-10-10 20:14:07 +09:00
lguest Merge branch 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-07 21:04:56 +09:00
macintosh Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2012-10-06 03:16:12 +09:00
md MD RAID10: Fix oops when creating RAID10 arrays via dm-raid.c 2012-10-31 11:42:30 +11:00
media [media] Kconfig: Fix dependencies for driver autoselect options 2012-10-17 16:45:56 -03:00
memory memory: tegra{20,30}-mc: Fix reading incorrect register in mc_readl() 2012-09-26 14:04:09 -07:00
memstick
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message
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mfd 1. New drivers: 2012-10-07 17:29:24 +09:00
misc pwm: Changes for v3.7-rc1 2012-10-10 20:15:24 +09:00
mmc mmc: mxs-mmc: Fix merge issue causing build error 2012-10-11 17:21:40 -04:00
mtd mtd: Disable mtdchar mmap on MMU systems 2012-10-09 15:08:42 +01:00
net vmxnet3: must split too big fragments 2012-11-02 21:58:09 -04:00
nfc NFC: Fix missing mutex unlock in pn533_send_cmd_frame_async 2012-09-27 10:47:48 +02:00
nubus
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of of/platform: sparse fix 2012-10-17 15:53:03 -05:00
oprofile mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file 2012-10-09 16:22:18 +09:00
parisc
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parport Xtensa patchset for 3.7 2012-10-09 16:11:46 +09:00
pci Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2012-10-06 03:16:12 +09:00
pcmcia Merge branch 'testing/driver-warnings' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc into fixes 2012-10-19 15:40:18 -07:00
pinctrl pinctrl/nomadik: pass DT node to the irqdomain 2012-10-23 11:52:25 +02:00
platform Merge branches 'fixes-for-37', 'ec' and 'thermal' into release 2012-10-09 01:47:35 -04:00
pnp
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power Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-10-13 11:27:59 +09:00
pps idr: rename MAX_LEVEL to MAX_IDR_LEVEL 2012-10-06 03:04:56 +09:00
ps3
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ptp
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pwm pwm: Changes for v3.7-rc1 2012-10-10 20:15:24 +09:00
rapidio rapidio: update for destination ID allocation 2012-10-11 08:50:15 +09:00
regulator MFD bits for the 3.7 merge window. 2012-10-05 12:01:30 +09:00
remoteproc Merge branch 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-07 21:04:56 +09:00
rpmsg Merge branch 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-07 21:04:56 +09:00
rtc drivers/rtc/rtc-imxdi.c: add missing spin lock initialization 2012-10-25 14:37:53 -07:00
s390 s390/css: stop stsch loop after cc 3 2012-10-18 17:50:08 +02:00
sbus
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scsi qla2xxx: Update target lookup session tables when a target session changes 2012-10-26 12:29:46 -07:00
sfi
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sh sh: Fix up more fallout from pointless ARM __iomem churn. 2012-10-15 14:08:48 +09:00
sn
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spi spi: Some minor MXS fixes 2012-10-28 11:13:54 -07:00
ssb
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staging Staging driver fixes for 3.7-rc3 2012-10-26 10:25:31 -07:00
target target: Fix incorrect usage of nested IRQ spinlocks in ABORT_TASK path 2012-11-01 00:38:45 -07:00
tc
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thermal exynos4_tmu_driver_ids should be exynos_tmu_driver_ids. 2012-11-03 09:52:55 +08:00
tty Revert "serial: omap: fix software flow control" 2012-10-24 11:57:21 -07:00
uio mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
usb xhci: trivial: Remove assigned but unused ep_ctx. 2012-10-25 13:13:48 -07:00
uwb
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vfio vfio: Fix PCI INTx disable consistency 2012-10-10 09:10:32 -06:00
vhost vhost: fix mergeable bufs on BE hosts 2012-10-24 23:19:30 -04:00
video Bug-fixes: 2012-11-02 13:26:11 -07:00
virt
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virtio virtio_mmio: Don't attempt to create empty virtqueues 2012-09-28 15:05:16 +09:30
vlynq
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vme
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w1 char/misc driver merge for 3.7-rc1 2012-10-01 12:09:59 -07:00
watchdog Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2012-10-07 21:06:10 +09:00
xen Bug-fixes: 2012-11-02 13:26:11 -07:00
zorro
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Kconfig ARM: soc: driver specific changes 2012-10-01 18:46:13 -07:00
Makefile IPMI: Change link order 2012-10-16 18:07:12 -07:00