linux/drivers
Jarkko Nikula cd998ded5c i2c: designware: Prevent runtime suspend during adapter registration
There can be unnecessary runtime suspend-resume cycle during
i2c-designware-platdrv probe when it registers the I2C adapter device. This
happens because i2c-designware-platdrv is set to initially active platform
device in its probe function and is a parent of I2C adapter.

In that case power.usage_count of i2c-designware device is zero and
pm_runtime_get()/pm_runtime_put() cycle during probe could put it into
runtime suspend. This happens when the i2c_register_adapter() calls the
device_register():

i2c_register_adapter
  device_register
    device_add
      bus_probe_device
        device_initial_probe
          __device_attach
            if (dev->parent) pm_runtime_get_sync(dev->parent)
            ...
            if (dev->parent) pm_runtime_put(dev->parent)

After that the i2c_register_adapter() continues registering I2C slave
devices. In case slave device probe does I2C transfers the parent will
resume again and thus get a needless runtime suspend/resume cycle during
adapter registration.

Prevent this while retaining the runtime PM status of i2c-designware by
only incrementing/decrementing device power usage count during I2C
adapter registration. That makes sure there won't be spurious runtime PM
status changes and lets the driver core to idle the device after probe
finishes.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-02-12 20:40:14 +01:00
..
accessibility
acpi Merge branches 'pm-core' and 'pm-domains' 2016-02-06 00:34:01 +01:00
amba
android
ata Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2016-01-11 19:33:59 -08:00
atm
auxdisplay
base Merge branches 'pm-core' and 'pm-domains' 2016-02-06 00:34:01 +01:00
bcma GPIO bulk updates for the v4.5 kernel cycle: 2016-01-17 12:32:01 -08:00
block Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2016-01-24 12:34:13 -08:00
bluetooth Bluetooth: btmrvl: don't send data to firmware while processing suspend 2016-01-06 16:37:14 +01:00
bus vexpress fixes for v4.5 2016-02-01 12:27:18 -08:00
cdrom cdrom: don't open-code memdup_user() 2016-01-06 08:25:24 -05:00
char Fix a compile error on IPMI when ACPI is disabled. 2016-02-03 10:04:58 -08:00
clk ARM: DT updates for v4.5 2016-01-20 18:16:29 -08:00
clocksource Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-01-31 15:49:06 -08:00
connector connector: bump skb->users before callback invocation 2016-01-04 21:46:45 -05:00
cpufreq Merge branches 'pm-cpuidle', 'pm-cpufreq', 'pm-domains' and 'pm-sleep' 2016-01-29 21:45:17 +01:00
cpuidle Merge branches 'pm-cpuidle', 'pm-cpufreq', 'pm-domains' and 'pm-sleep' 2016-01-29 21:45:17 +01:00
crypto crypto: atmel-aes - remove calls of clk_prepare() from atomic contexts 2016-01-30 22:05:17 +08:00
dca
devfreq PM / devfreq: Do not show statistics if it's not ready. 2016-01-13 17:30:33 +09:00
dio
dma dmaengine fixes for 4.5-rc1 2016-01-20 10:15:21 -08:00
dma-buf
edac
eisa
extcon
firewire
firmware UBSAN: run-time undefined behavior sanity checker 2016-01-20 17:09:18 -08:00
fmc
fpga
gpio ARM: SoC multiplatform code changes for v4.5 2016-01-20 18:03:56 -08:00
gpu Merge branch 'drm-fixes-mst' of git://people.freedesktop.org/~airlied/linux into drm-fixes 2016-02-05 15:24:17 +10:00
hid asm-generic changes for 4.5 2016-01-20 17:30:20 -08:00
hsi HSI: omap_ssi_port: fix handling of_get_named_gpio result 2016-01-07 16:07:54 +01:00
hv char/misc patches for 4.5-rc1 2016-01-13 10:23:36 -08:00
hwmon hwmon: (fam15h_power) Add bit masking for tdp_limit 2016-01-27 18:48:46 -08:00
hwspinlock drivers/hwspinlock: fix race between radix tree insertion and lookup 2016-02-03 08:28:43 -08:00
hwtracing
i2c i2c: designware: Prevent runtime suspend during adapter registration 2016-02-12 20:40:14 +01:00
ide drivers/ide: make ide-scan-pci.c driver explicitly non-modular 2016-01-18 14:12:33 -05:00
idle
iio Second set of IIO fixes for the 4.5 cycle. These ones are mostly 2016-02-01 13:08:26 -08:00
infiniband IB/core: Set correct payload length for RoCEv2 over IPv6 2016-02-02 16:42:22 -05:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2016-01-22 17:20:30 -08:00
iommu iommu/amd: Correct the wrong setting of alias DTE in do_attach 2016-01-29 12:30:47 +01:00
ipack
irqchip Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-01-31 14:48:58 -08:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-01-11 23:55:43 -05:00
leds GPIO bulk updates for the v4.5 kernel cycle: 2016-01-17 12:32:01 -08:00
lguest lguest: Map switcher text R/O 2016-01-12 12:17:28 +01:00
lightnvm lightnvm: introduce factory reset 2016-01-12 08:21:18 -07:00
macintosh
mailbox mailbox: Fix dependencies for !HAS_IOMEM archs 2016-02-02 16:47:14 +05:30
mcb
md Merge branch 'mymd/for-next' into mymd/for-linus 2016-02-03 15:43:59 -08:00
media [media] saa7134-alsa: Only frees registered sound cards 2016-02-04 16:26:10 -02:00
memory ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
memstick memstick: use sector_div instead of do_div 2016-01-20 17:09:18 -08:00
message
mfd GPIO bulk updates for the v4.5 kernel cycle: 2016-01-17 12:32:01 -08:00
misc Merge branch 'akpm' (patches from Andrew) 2016-01-21 12:32:08 -08:00
mmc MMC core: 2016-01-22 12:04:21 -08:00
mtd Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-01-24 12:50:56 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-02-01 15:56:08 -08:00
nfc
ntb NTB: Fix macro parameter conflict with field name 2016-01-21 19:53:10 -05:00
nubus
nvdimm libnvdimm, pfn: fix restoring memmap location 2016-01-29 17:43:16 -08:00
nvme Merge branch 'for-4.5/nvme' of git://git.kernel.dk/linux-block 2016-01-21 19:58:02 -08:00
nvmem
of Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-02-01 15:56:08 -08:00
oprofile wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
parisc parisc: convert to dma_map_ops 2016-01-20 17:09:18 -08:00
parport
pci Merge branches 'acpi-video' and 'acpi-hotplug' 2016-01-29 21:44:53 +01:00
pcmcia
perf
phy
pinctrl GPIO bulk updates for the v4.5 kernel cycle: 2016-01-17 12:32:01 -08:00
platform ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list 2016-01-24 10:15:01 -08:00
pnp PNP: Add Haswell-ULT to Intel MCH size workaround 2016-02-03 01:00:29 +01:00
power power: bq27xxx_battery: Fix bq27541 AveragePower register address 2016-01-14 01:03:18 +01:00
powercap Merge branch 'powercap' 2016-01-12 01:12:40 +01:00
pps
ps3
ptp ptp: ixp46x: use helpers for converting ns to timespec 2016-01-29 12:38:59 -08:00
pwm pwm: Mark all devices as "might sleep" 2016-01-21 15:04:59 +01:00
rapidio rapidio: use kobj_to_dev() 2016-01-20 17:09:18 -08:00
ras
regulator regulator: Update for v4.5 2016-01-15 12:14:47 -08:00
remoteproc virtio: make find_vqs() checkpatch.pl-friendly 2016-01-12 20:47:06 +02:00
reset
rpmsg virtio: make find_vqs() checkpatch.pl-friendly 2016-01-12 20:47:06 +02:00
rtc RTC for 4.5 2016-01-18 12:10:45 -08:00
s390 s390/cio: update measurement characteristics 2016-01-26 12:47:51 +01:00
sbus convert a bunch of open-coded instances of memdup_user_nul() 2016-01-04 10:26:58 -05:00
scsi drivers/scsi/sg.c: mark VMA as VM_IO to prevent migration 2016-02-03 08:28:43 -08:00
sfi
sh
sn
soc ARM: SoC support for Tegra platforms for v4.5 2016-01-22 17:30:52 -08:00
spi powerpc updates for 4.5 2016-01-15 13:18:47 -08:00
spmi
ssb ssb: mark ssb_bus_register as __maybe_unused 2016-01-19 21:25:57 +02:00
staging Staging / IIO driver fixes for 4.5-rc3 2016-02-06 22:13:16 -08:00
target Merge branch 'for-4.5/nvme' of git://git.kernel.dk/linux-block 2016-01-21 19:58:02 -08:00
tc
thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2016-01-24 12:43:06 -08:00
thunderbolt
tty TTY/Serial fixes for 4.5-rc2 2016-01-31 17:09:39 -08:00
uio
usb xhci: harden xhci_find_next_ext_cap against device removal 2016-02-04 17:00:10 -08:00
uwb
vfio vfio/noiommu: Don't use iommu_present() to track fake groups 2016-01-27 11:22:25 -07:00
vhost
video wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
virt
virtio virtio_pci: fix use after free on release 2016-01-26 10:18:28 +02:00
vlynq
vme
w1
watchdog watchdog: Fix dependencies for !HAS_IOMEM archs 2016-01-31 16:54:36 +01:00
xen Merge branch 'stable/for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm 2016-01-29 15:13:48 -08:00
zorro
Kconfig
Makefile