linux/Documentation
Daniel Glöckner ff77c352ae gpiolib: allow poll() on value
Many gpio chips allow to generate interrupts when the value of a pin
changes.  This patch gives usermode application the opportunity to make
use of this feature by calling poll(2) on the /sys/class/gpio/gpioN/value
sysfs file.  The edge to trigger can be set in the edge file in the same
directory.  Possible values are "none", "rising", "falling", and "both".

Using level triggers is not possible with current sysfs since nothing
changes the GPIO value (and the IRQ keeps triggering).  Edge triggering
will "just work".  Note that if there was an event between read() and
poll(), the poll() returns immediately.

Also note that this version only supports true GPIO interrupts.  Some
later patch might be able to synthesize this behavior by timer-driven
polling; some systems seem to need that.

[dbrownell@users.sourceforge.net: align ids to 16 bit ids; whitespace]
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:48 -07:00
..
ABI gpiolib: allow poll() on value 2009-09-23 07:39:48 -07:00
DocBook Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-09-22 07:51:45 -07:00
PCI PCI: document PCIe fundamental reset interfaces 2009-09-09 13:29:38 -07:00
RCU rcu: Remove CONFIG_PREEMPT_RCU 2009-08-23 10:32:40 +02:00
accounting Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
acpi ACPI: update debug parameter documentation 2008-11-07 21:45:29 -05:00
aoe aoe: user can ask driver to forget previously detected devices 2008-02-08 09:22:31 -08:00
arm Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-09-18 09:19:26 -07:00
auxdisplay Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
blackfin Blackfin arch: Add document about bfin-gpio 2009-01-07 23:14:38 +08:00
block Trivial typo fixes in Documentation/block/data-integrity.txt. 2009-07-01 10:56:25 +02:00
blockdev mflash: initial support 2009-04-07 08:12:38 +02:00
cdrom debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
cgroups cpusets: document adding/removing cpus to cpuset elaborately 2009-06-30 18:56:01 -07:00
connector Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-23 19:03:51 -07:00
console Typo: fro -> from 2007-07-19 10:04:47 -07:00
cpu-freq [CPUFREQ] update Doc for cpuinfo_cur_freq and scaling_cur_freq 2009-09-01 12:45:09 -04:00
cpuidle cpuidle: Add Documentation 2008-02-14 00:16:13 -05:00
cris fix random typos 2008-10-16 11:21:30 -07:00
crypto async_tx, dmaengine: document channel allocation and api rework 2009-01-05 18:10:19 -07:00
development-process docs: Encourage better changelogs in the development process document 2009-06-04 10:32:49 -06:00
device-mapper dm raid1: add userspace log 2009-06-22 10:12:35 +01:00
driver-model driver model: fix show/store prototypes in doc. 2009-07-12 13:02:10 -07:00
dvb V4L/DVB (12902): Documentation: synchronize documentation for Technisat cards 2009-09-19 00:14:32 -03:00
early-userspace Documentation: Remove last references to BitKeeper. 2008-04-21 22:19:05 +00:00
fault-injection debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
fb Documentation/fb/vesafb.txt: fix typo 2009-06-16 19:47:58 -07:00
filesystems ncpfs: remove dead URL from documentation 2009-09-23 07:39:42 -07:00
firmware_class driver core: fix documentation of request_firmware_nowait 2009-06-15 21:30:24 -07:00
frv move frv docs one level up 2008-02-03 15:54:28 +02:00
hwmon trivial: doc: hpfall: accept disk device to unload as argument 2009-09-21 15:14:57 +02:00
i2c i2c: Add a sysfs interface to instantiate devices 2009-06-19 16:58:20 +02:00
i2o
ia64 Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
ide ide: preserve Host Protected Area by default (v2) 2009-06-07 13:52:52 +02:00
infiniband IPoIB: Document newish features 2009-04-08 13:52:01 -07:00
input Input: add new driver for Sentelic Finger Sensing Pad 2009-08-19 21:46:09 -07:00
ioctl Merge branch 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2009-09-14 17:43:43 -07:00
isdn isdn: clean up documentation index 2009-06-20 01:10:38 -07:00
ja_JP block: rename CONFIG_LBD to CONFIG_LBDAF 2009-06-19 08:08:50 +02:00
kbuild kconfig: resort the documentation of the environment variables 2009-06-09 22:37:47 +02:00
kdump trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
ko_KR HOWTO: update misspelling and word incorrected 2007-12-17 10:33:19 -08:00
kvm KVM: Document KVM_CAP_IRQCHIP 2009-09-10 10:46:55 +03:00
laptops thinkpad-acpi: remove dock and bay subdrivers 2009-08-01 23:46:58 -04:00
lguest lguest and virtio: cleanup struct definitions to Linux style. 2009-07-30 16:03:46 +09:30
m68k [SCSI] 53c7xx: fix removal fallout 2008-01-11 18:22:30 -06:00
make Documentation/make/headers_install.txt 2007-10-17 08:43:05 -07:00
mips ide: remove unused CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ 2009-01-14 19:19:03 +01:00
misc-devices drivers/misc/isl29003.c: driver for the ISL29003 ambient light sensor 2009-04-01 08:59:18 -07:00
mn10300 trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
mtd trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
namespaces The namespaces compatibility list doc 2007-11-29 09:24:53 -08:00
netlabel
networking trivial: fix typo "to to" in multiple files 2009-09-21 15:14:55 +02:00
parisc
pcmcia Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
power PM: Introduce core framework for run-time PM of I/O devices (rev. 17) 2009-08-23 00:04:44 +02:00
powerpc powerpc: introduce and document sdhci,wp-inverted property for eSDHC 2009-09-23 07:39:37 -07:00
pps LinuxPPS: core support 2009-06-18 13:04:04 -07:00
prctl generic, x86: add tests for prctl PR_GET_TSC and PR_SET_TSC 2008-04-19 19:19:55 +02:00
s390 [S390] s390dbf: Add description for usage of "%s" in sprintf events 2009-09-11 10:29:53 +02:00
scheduler sched: Documentation/sched-rt-group: Fix style issues & bump version 2009-06-21 13:12:46 +02:00
scsi trivial: fix typos "man[ae]g?ment" -> "management" 2009-09-21 15:14:56 +02:00
serial Create/use more directory structure in the Documentation/ tree. 2008-11-14 17:28:53 +00:00
sh sh: Kill off remaining CONFIG_SH_KGDB bits. 2008-12-22 18:44:05 +09:00
sound trivial: fix typos "man[ae]g?ment" -> "management" 2009-09-21 15:14:56 +02:00
sparc sparc: Remove Documentation/sparc/sbus_drivers.txt 2008-08-29 02:15:25 -07:00
spi spi: fix spelling of `automatically' in documentation 2009-09-23 07:39:44 -07:00
sysctl printk: add printk_delay to make messages readable for some scenarios 2009-09-23 07:39:28 -07:00
telephony remove mention of CONFIG_KMOD from documentation 2008-07-22 19:24:29 +10:00
thermal thermal: update the documentation 2008-04-29 02:49:47 -04:00
timers trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-09-22 07:51:45 -07:00
uml
usb trivial: usb: fix missing space typo in doc 2009-06-12 18:01:51 +02:00
video4linux Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
vm Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
w1 w1: send status messages after command processing 2009-01-08 08:31:14 -08:00
watchdog Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
wimax i2400m: documentation and instructions for usage 2009-01-07 10:00:18 -08:00
x86 Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-09-18 14:05:47 -07:00
zh_CN Chinese: add translation of Codingstyle 2008-01-24 20:40:04 -08:00
00-INDEX Bluetooth: Add documentation for Marvell Bluetooth driver 2009-08-22 14:25:32 -07:00
BUG-HUNTING Documentation: add hint about call traces & module symbols to BUG-HUNTING 2008-02-06 10:41:09 -08:00
Changes Documentation/Changes: perl is needed to build the kernel 2009-06-18 13:03:46 -07:00
CodingStyle trivial: fix typo milisecond/millisecond for documentation and source comments. 2009-06-12 18:01:46 +02:00
DMA-API.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
DMA-ISA-LPC.txt
DMA-attributes.txt powerpc/cell: Add DMA_ATTR_WEAK_ORDERING dma attribute and use in Cell IOMMU code 2008-07-22 10:39:36 +10:00
DMA-mapping.txt dma-mapping: update the old macro DMA_nBIT_MASK related documentations 2009-04-07 08:31:12 -07:00
HOWTO Remove Andrew Morton's http://www.zip.com.au/~akpm/ 2008-10-16 11:21:32 -07:00
IO-mapping.txt Documentation: move DMA-mapping.txt to Doc/PCI/ 2009-01-29 18:19:29 -08:00
IPMI.txt IPMI: new NMI handling 2007-10-18 14:37:32 -07:00
IRQ-affinity.txt genirq: Expose default irq affinity mask (take 3) 2008-06-05 15:18:30 +02:00
IRQ.txt
Intel-IOMMU.txt Documentation cleanup: trivial misspelling, punctuation, and grammar corrections. 2008-07-26 12:00:06 -07:00
Makefile docsrc: build Documentation/ sources 2008-08-12 16:07:30 -07:00
ManagementStyle docs: fix ManagementStyle book name 2008-10-30 11:38:46 -07:00
SAK.txt Remove Andrew Morton's old email accounts 2008-10-16 11:21:32 -07:00
SELinux.txt selinux: add support for installing a dummy policy (v2) 2008-08-27 08:54:08 +10:00
SM501.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
SecurityBugs
Smack.txt smack: implement logging V3 2009-04-14 09:00:23 +10:00
SubmitChecklist block: rename CONFIG_LBD to CONFIG_LBDAF 2009-06-19 08:08:50 +02:00
SubmittingDrivers Remove Andrew Morton's old email accounts 2008-10-16 11:21:32 -07:00
SubmittingPatches trivial: SubmittingPatches: Fix reference to renumbered step 2009-09-21 15:14:57 +02:00
VGA-softcursor.txt
applying-patches.txt
atomic_ops.txt Documentation/atomic_ops.txt: fix sample code 2009-06-16 19:47:52 -07:00
bad_memory.txt Document handling of bad memory 2008-12-03 16:09:53 -07:00
basic_profiling.txt
binfmt_misc.txt
braille-console.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
bt8xxgpio.txt gpio: add bt8xxgpio driver 2008-07-25 10:53:30 -07:00
btmrvl.txt Bluetooth: Add documentation for Marvell Bluetooth driver 2009-08-22 14:25:32 -07:00
c2port.txt Add c2 port support 2008-11-12 17:17:18 -08:00
cachetlb.txt remove unused flush_tlb_pgtables 2007-10-19 11:53:34 -07:00
cpu-hotplug.txt x86: use possible_cpus=NUM to extend the possible cpus allowed 2008-12-18 12:08:05 +01:00
cpu-load.txt
cputopology.txt cpumask: Use topology_core_cpumask()/topology_thread_cpumask() 2009-01-11 19:12:49 +01:00
credentials.txt CRED: Documentation 2008-11-14 10:39:26 +11:00
dcdbas.txt
debugging-modules.txt Documentation: Clarify when module debugging actually works. 2008-02-03 15:27:38 +02:00
debugging-via-ohci1394.txt firewire: fw-ohci: add option for remote debugging 2008-04-18 17:55:33 +02:00
dell_rbu.txt trivial: Documentation/dell_rbu.txt: fix typos 2009-06-12 18:01:50 +02:00
devices.txt lanana: assign a device name and numbering for MAX3100 2009-04-07 08:44:05 -07:00
dmaengine.txt async_tx, dmaengine: document channel allocation and api rework 2009-01-05 18:10:19 -07:00
dontdiff sparc: Kill PROM console driver. 2009-09-15 17:04:38 -07:00
dynamic-debug-howto.txt Dynamic debug: allow simple quoting of words 2009-03-24 16:38:27 -07:00
edac.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
eisa.txt
email-clients.txt Documentation/email-clients.txt: add some info about gmail 2008-11-06 15:41:19 -08:00
feature-removal-schedule.txt Merge branch 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-09-17 21:07:08 -07:00
flexible-arrays.txt Document the flex_array library. 2009-09-10 14:33:36 -06:00
futex-requeue-pi.txt futex: add requeue-pi documentation 2009-05-09 07:12:50 +02:00
gcov.txt trivial: fix typo in CONFIG_DEBUG_FS in gcov doc 2009-09-21 15:14:56 +02:00
gpio.txt gpiolib: allow poll() on value 2009-09-23 07:39:48 -07:00
highuid.txt [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
hw_random.txt hw_random doc updates 2008-03-24 19:22:19 -07:00
ics932s401 ics932s401: new clock generator chip driver 2008-11-12 17:17:18 -08:00
initrd.txt use the newc archive format as requested by initramfs 2008-02-03 14:54:41 +02:00
intel_txt.txt x86, intel_txt: Intel TXT boot support 2009-07-21 11:49:06 -07:00
io-mapping.txt io mapping: improve documentation 2008-11-03 18:21:44 +01:00
io_ordering.txt
iostats.txt Documentation cleanup: trivial misspelling, punctuation, and grammar corrections. 2008-07-26 12:00:06 -07:00
irqflags-tracing.txt
isapnp.txt
java.txt Documentation/java.txt: typo and grammar fixes 2007-10-20 02:37:21 +02:00
kernel-doc-nano-HOWTO.txt kernel-doc: allow multi-line declaration purpose descriptions 2009-09-18 09:48:52 -07:00
kernel-docs.txt doc: update to URL and status of kernel-docs.txt entry 2008-06-06 11:29:10 -07:00
kernel-parameters.txt trivial: typo in kernel-parameters.txt 2009-09-21 15:15:52 +02:00
keys-request-key.txt keys: allow the callout data to be passed as a blob rather than a string 2008-04-29 08:06:16 -07:00
keys.txt KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] 2009-09-02 21:29:22 +10:00
kmemcheck.txt kmemcheck: update documentation 2009-07-01 22:36:22 +02:00
kmemleak.txt kmemleak: add clear command support 2009-09-08 16:36:08 +01:00
kobject.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
kprobes.txt debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
kref.txt kref: double kref_put() in my_data_handler() 2009-09-18 09:48:52 -07:00
ldm.txt
leds-class.txt Documentation cleanup: trivial misspelling, punctuation, and grammar corrections. 2008-07-26 12:00:06 -07:00
leds-lp3944.txt leds: LED driver for National Semiconductor LP3944 Funlight Chip 2009-06-23 20:21:38 +01:00
local_ops.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
lockdep-design.txt lockdep: Fix typos in documentation 2009-08-07 12:03:46 +02:00
lockstat.txt lockstat: contend with points 2008-10-20 15:43:10 +02:00
logo.gif Revert "linux.conf.au 2009: Tuz" 2009-04-27 12:00:27 -07:00
logo.txt Revert "linux.conf.au 2009: Tuz" 2009-04-27 12:00:27 -07:00
magic-number.txt documentation: update header file paths 2009-01-06 15:59:28 -08:00
mca.txt The ps2esdi driver was marked as BROKEN more than two years ago due to being 2008-03-17 09:03:05 +01:00
md.txt Documentation/md.txt update 2009-03-31 15:18:37 +11:00
memory-barriers.txt sched: Document memory barriers implied by sleep/wake-up primitives 2009-04-29 14:15:55 +02:00
memory-hotplug.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
memory.txt Documentation/memory.txt: remove some very outdated recommendations 2009-09-22 07:17:26 -07:00
mono.txt
mutex-design.txt Documentation: Add nested versions of mutex locks to docs 2007-10-20 00:15:26 +02:00
nmi_watchdog.txt x86, nmi-watchdog: update procfs nmi_watchdog file documentation v2 2008-10-30 19:07:04 +01:00
nommu-mmap.txt NOMMU: Make mmap allocation page trimming behaviour configurable. 2009-01-08 12:04:47 +00:00
numastat.txt mm: fix NUMA accounting in numastat.txt 2009-09-22 07:17:39 -07:00
oops-tracing.txt Taint kernel after WARN_ON(condition) 2008-04-29 08:05:59 -07:00
parport-lowlevel.txt plip: fix parport_register_device name parameter 2007-11-26 19:39:01 -08:00
parport.txt
pi-futex.txt
pnp.txt Documentation: Replace obsolete "driverfs" with "sysfs". 2008-01-24 20:40:04 -08:00
preempt-locking.txt
printk-formats.txt DOC: add printk-formats.txt 2008-11-12 17:17:17 -08:00
prio_tree.txt
rbtree.txt trivial: rbtree.txt: fix rb_entry() parameters in sample code 2009-06-12 18:01:47 +02:00
rfkill.txt rfkill: export persistent attribute in sysfs 2009-06-19 11:50:18 -04:00
robust-futex-ABI.txt futex: documentation: fix inconsistent description of futex list_op_pending 2009-06-18 13:03:56 -07:00
robust-futexes.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt rtc: add boot_timesource sysfs attribute 2009-09-23 07:39:46 -07:00
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
slow-work.txt Document the slow work thread pool 2009-04-03 16:42:35 +01:00
sparse.txt Documentation: explain the difference between __bitwise and __bitwise__ 2009-04-11 08:18:11 +02:00
spinlocks.txt Add additional examples in Documentation/spinlocks.txt 2008-04-11 13:21:14 -06:00
stable_api_nonsense.txt stable_api_nonsense.txt: Disambiguate the use of "this" by using "that" to refer to the syscall interface 2007-07-30 14:25:12 -07:00
stable_kernel_rules.txt Update stable tree documentation 2008-10-29 15:03:49 -07:00
svga.txt
sysfs-rules.txt Doc/sysfs-rules: Swap the order of the words so the sentence makes more sense 2009-05-08 19:22:20 -07:00
sysrq.txt sysrq, kdump: make sysrq-c consistent 2009-07-29 19:10:36 -07:00
tomoyo.txt tomoyo: add Documentation/tomoyo.txt 2009-04-14 09:14:58 +10:00
unaligned-memory-access.txt introduce HAVE_EFFICIENT_UNALIGNED_ACCESS Kconfig symbol 2008-07-25 10:53:27 -07:00
unicode.txt
unshare.txt
vgaarbiter.txt PCI/VGA: add VGA arbitration documentation 2009-09-09 13:29:42 -07:00
video-output.txt
volatile-considered-harmful.txt Documentation cleanup: trivial misspelling, punctuation, and grammar corrections. 2008-07-26 12:00:06 -07:00
voyager.txt
zorro.txt