linux/drivers
Lukas Wunner 4e6a13356f PCI: pciehp: Deduplicate presence check on probe & resume
On driver probe and on resume from system sleep, pciehp checks the
Presence Detect State bit in the Slot Status register to bring up an
occupied slot or bring down an unoccupied slot.  Both code paths are
identical, so deduplicate them per Mika's request.

On probe, an additional check is performed to disable power of an
unoccupied slot.  This can e.g. happen if power was enabled by BIOS.
It cannot happen once pciehp has taken control, hence is not necessary
on resume:  The Slot Control register is set to the same value that it
had on suspend by pci_restore_state(), so if the slot was occupied,
power is enabled and if it wasn't, power is disabled.  Should occupancy
have changed during the system sleep transition, power is adjusted by
bringing up or down the slot per the paragraph above.

To allow for deduplication of the presence check, move the power check
to pcie_init().  This seems safer anyway, because right now it is
performed while interrupts are already enabled, and although I can't
think of a scenario where pciehp_power_off_slot() and the IRQ thread
collide, it does feel brittle.

However this means that pcie_init() may now write to the Slot Control
register before the IRQ is requested.  If both the CCIE and HPIE bits
happen to be set, pcie_wait_cmd() will wait for an interrupt (instead
of polling the Command Completed bit) and eventually emit a timeout
message.  Additionally, if a level-triggered INTx interrupt is used,
the user may see a spurious interrupt splat.  Avoid by disabling
interrupts before disabling power.  (Normally the HPIE and CCIE bits
should be clear on probe, but conceivably they may already have been
set e.g. by BIOS.)

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2018-07-31 13:27:24 -05:00
..
accessibility
acpi pwm: Changes for v4.18-rc1 2018-06-14 16:25:43 +09:00
amba Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm 2018-06-06 13:49:25 -07:00
android treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
ata treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
atm treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
auxdisplay treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
base Additional power management updates for 4.18-rc1 2018-06-13 07:24:18 -07:00
bcma dma-mapping updates for 4.18: 2018-06-04 10:58:12 -07:00
block The main piece is a set of libceph changes that revamps how OSD 2018-06-15 07:24:58 +09:00
bluetooth
bus - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
cdrom treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
char docs: Fix some broken references 2018-06-15 18:10:01 -03:00
clk docs: Fix some broken references 2018-06-15 18:10:01 -03:00
clocksource treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
connector Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
cpufreq Additional power management updates for 4.18-rc1 2018-06-13 07:24:18 -07:00
cpuidle powerpc updates for 4.18 2018-06-07 10:23:33 -07:00
crypto treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
dax libnvdimm for 4.18 2018-06-08 17:21:52 -07:00
dca
devfreq treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
dio
dma fix a series of Documentation/ broken file name references 2018-06-15 18:10:01 -03:00
dma-buf
edac treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
eisa
extcon treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
firewire treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
firmware Merge branch 'akpm' (patches from Andrew) 2018-06-15 08:51:42 +09:00
fmc treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
fpga
fsi
gpio treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpu Solve a series of broken links for files under Documentation: 2018-06-17 05:25:18 +09:00
hid docs: fix broken references with multiple hints 2018-06-15 18:10:01 -03:00
hsi
hv treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
hwmon treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
hwspinlock hwspinlock updates for v4.18 2018-06-11 12:09:19 -07:00
hwtracing treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
i2c Merge branch 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2018-06-14 16:21:46 +09:00
ide treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
idle
iio treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
infiniband treewide: Use array_size() in kvzalloc_node() 2018-06-12 16:19:22 -07:00
input docs: Fix some broken references 2018-06-15 18:10:01 -03:00
iommu - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
ipack treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
irqchip treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
isdn treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
leds treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
lightnvm docs: Fix some broken references 2018-06-15 18:10:01 -03:00
macintosh powerpc updates for 4.18 2018-06-07 10:23:33 -07:00
mailbox treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
mcb
md docs: Fix some broken references 2018-06-15 18:10:01 -03:00
media Solve a series of broken links for files under Documentation: 2018-06-17 05:25:18 +09:00
memory - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
memstick treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
message treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
mfd Merge branch 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2018-06-14 16:21:46 +09:00
misc Merge branch 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2018-06-14 16:21:46 +09:00
mmc treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
mtd - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
mux
net Solve a series of broken links for files under Documentation: 2018-06-17 05:25:18 +09:00
nfc treewide: devm_kmalloc() -> devm_kmalloc_array() 2018-06-12 16:19:22 -07:00
ntb - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
nubus Char/Misc driver patches for 4.18-rc1 2018-06-05 16:20:22 -07:00
nvdimm Merge branch 'for-4.18/mcsafe' into libnvdimm-for-next 2018-06-08 15:16:44 -07:00
nvme Merge branch 'nvme-4.18' of git://git.infradead.org/nvme into for-linus 2018-06-15 08:11:05 -06:00
nvmem treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
of - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
opp treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
oprofile treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
parisc dma-mapping updates for 4.18: 2018-06-04 10:58:12 -07:00
parport docs: Fix some broken references 2018-06-15 18:10:01 -03:00
pci PCI: pciehp: Deduplicate presence check on probe & resume 2018-07-31 13:27:24 -05:00
pcmcia treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
perf
phy Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
pinctrl treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
platform PCI: hotplug: Demidlayer registration with the core 2018-07-23 17:04:13 -05:00
pnp media updates for v4.18-rc1 2018-06-07 12:34:37 -07:00
power treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
powercap treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
pps
ps3
ptp
pwm pwm: Changes for v4.18-rc1 2018-06-14 16:25:43 +09:00
rapidio treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
ras
regulator treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
remoteproc treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX 2018-06-15 07:55:25 +09:00
reset - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
rpmsg rpmsg: smd: do not use mananged resources for endpoints and channels 2018-06-04 12:35:03 -07:00
rtc - New Device Support 2018-06-11 07:20:17 -07:00
s390 treewide: Use array_size() in vzalloc() 2018-06-12 16:19:22 -07:00
sbus fix a series of Documentation/ broken file name references 2018-06-15 18:10:01 -03:00
scsi SCSI fixes on 20180613 2018-06-14 16:35:32 +09:00
sfi
sh treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
siox
slimbus treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
sn
soc treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX 2018-06-15 07:55:25 +09:00
soundwire docs: Fix more broken references 2018-06-15 18:11:26 -03:00
spi treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
spmi
ssb
staging media: v4l: fix broken video4linux docs locations 2018-06-15 18:10:01 -03:00
target treewide: Use array_size() in vzalloc() 2018-06-12 16:19:22 -07:00
tc
tee
thermal - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
thunderbolt
tty vfs/y2038: inode timestamps conversion to timespec64 2018-06-15 07:31:07 +09:00
uio treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
usb vfs/y2038: inode timestamps conversion to timespec64 2018-06-15 07:31:07 +09:00
uwb treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
vfio VFIO updates for v4.18 2018-06-12 13:11:26 -07:00
vhost virtio, vhost: features, fixes 2018-06-16 06:35:02 +09:00
video Solve a series of broken links for files under Documentation: 2018-06-17 05:25:18 +09:00
virt treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
virtio virtio, vhost: features, fixes 2018-06-16 06:35:02 +09:00
visorbus
vlynq
vme
w1 Char/Misc driver patches for 4.18-rc1 2018-06-05 16:20:22 -07:00
watchdog MIPS changes for 4.18 2018-06-12 12:56:02 -07:00
xen treewide: kvmalloc() -> kvmalloc_array() 2018-06-12 16:19:22 -07:00
zorro - Introduce arithmetic overflow test helper functions (Rasmus) 2018-06-06 17:27:14 -07:00
Kconfig
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