linux/drivers
Linus Walleij fdeb8e1547 gpio: reflect base and ngpio into gpio_device
Some information about the GPIO chip need to stay around also
after the gpio_chip has been removed and only the gpio_device
persist. The base and ngpio are such things, for example we
don't want a new chip arriving to overlap the number space
of a dangling gpio_device, and the chardev may still query
the device for the number of lines etc.

Note that the code that assigns base and insert gpio_device
into the global list no longer check for a missing gpio_chip:
we respect the number space allocated by any other gpio_device.

As a consequence of the gdev being referenced directly from
the gpio_desc, we need to verify it differently from all
in-kernel API calls that fall through to direct queries to
the gpio_chip vtable: we first check that desc is !NULL, then
that desc->gdev is !NULL, then, if desc->gdev->chip is NULL,
we *BAIL OUT* without any error, so as to manage the case
where operations are requested on a device that is gone.

These checks were non-uniform and partly missing in the past:
so to simplify: create the macros VALIDATE_DESC() that will
return -EINVAL if the desc or desc->gdev is missing and just
0 if the chip is gone, and conversely VALIDATE_DESC_VOID()
for the case where the function does not return an error.
By using these macros, we get warning messages about missing
gdev with reference to the right function in the kernel log.

Despite the macro business this simplifies the code and make
it more readable than if we copy/paste the same descriptor
checking code into all code ABI call sites (IMHO).

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11 20:29:46 +01:00
..
accessibility
acpi tree wide: use kvfree() than conditional kfree()/vfree() 2016-01-22 17:02:18 -08:00
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 wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
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
bus ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
cdrom
char Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
clk ARM: DT updates for v4.5 2016-01-20 18:16:29 -08:00
clocksource ARM: SoC cleanups for v4.5 2016-01-20 17:55:20 -08:00
connector
cpufreq powerpc updates for 4.5 2016-01-15 13:18:47 -08:00
cpuidle More power management and ACPI updates for v4.5-rc1 2016-01-20 19:06:49 -08:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-01-22 11:58:43 -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 gpio: reflect base and ngpio into gpio_device 2016-02-11 20:29:46 +01:00
gpu tree wide: use kvfree() than conditional kfree()/vfree() 2016-01-22 17:02:18 -08:00
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 Merge git://www.linux-watchdog.org/linux-watchdog 2016-01-17 12:15:38 -08:00
hwspinlock
hwtracing
i2c Merge branch 'i2c/for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2016-01-14 11:25:37 -08:00
ide drivers/ide: make ide-scan-pci.c driver explicitly non-modular 2016-01-18 14:12:33 -05:00
idle
iio Merge branch 'akpm' (patches from Andrew) 2016-01-21 12:32:08 -08:00
infiniband Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
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 Updates for Linux v4.5 2016-01-19 09:35:06 -08:00
ipack
irqchip Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-01-24 12:50:56 -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
mcb
md Merge branch 'for-4.5/drivers' of git://git.kernel.dk/linux-block 2016-01-21 18:19:38 -08:00
media dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
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 Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
nfc
ntb NTB: Fix macro parameter conflict with field name 2016-01-21 19:53:10 -05:00
nubus
nvdimm mm, dax, pmem: introduce {get|put}_dev_pagemap() for dax-gup 2016-01-15 17:56:32 -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 DeviceTree updates for 4.5: 2016-01-14 11:13:28 -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 PCI changes for the v4.5 merge window: 2016-01-21 11:52:16 -08:00
pcmcia
perf
phy
pinctrl gpio/pinctrl: sunxi: stop poking around in private vars 2016-02-11 20:29:45 +01:00
platform ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list 2016-01-24 10:15:01 -08:00
pnp
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
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 virtio: barrier rework+fixes 2016-01-18 16:44:24 -08:00
sbus
scsi Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
sfi
sh
sn
soc powerpc: qe_lib/gpio: Be sure to clamp return value 2016-01-25 18:02:26 +01:00
spi powerpc updates for 4.5 2016-01-15 13:18:47 -08:00
spmi
ssb
staging Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -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 ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
uio
usb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
uwb
vfio
vhost
video wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
virt
virtio virtio: make find_vqs() checkpatch.pl-friendly 2016-01-12 20:47:06 +02:00
vlynq
vme
w1
watchdog watchdog: asm9260: remove __init and __exit annotations 2016-01-11 22:48:05 +01:00
xen virtio: barrier rework+fixes 2016-01-18 16:44:24 -08:00
zorro
Kconfig
Makefile