linux/Documentation
Daniel Vetter b0e898ac55 drm: remove FASYNC support
So I've stumbled over drm_fasync and wondered what it does. Digging
that up is quite a story.

First I've had to read up on what this does and ended up being rather
bewildered why peopled loved signals so much back in the days that
they've created SIGIO just for that ...

Then I wondered how this ever works, and what that strange "No-op."
comment right above it should mean. After all calling the core fasync
helper is pretty obviously not a noop. After reading through the
kernels FASYNC implementation I've noticed that signals are only sent
out to the processes attached with FASYNC by calling kill_fasync.

No merged drm driver has ever done that.

After more digging I've found out that the only driver that ever used
this is the so called GAMMA driver. I've frankly never heard of such a
gpu brand ever before. Now FASYNC seems to not have been the only bad
thing with that driver, since Dave Airlie removed it from the drm
driver with prejudice:

commit 1430163b4bbf7b00367ea1066c1c5fe85dbeefed
Author: Dave Airlie <airlied@linux.ie>
Date:   Sun Aug 29 12:04:35 2004 +0000

    Drop GAMMA DRM from a great height ...

Long story short, the drm fasync support seems to be doing absolutely
nothing. And the only user of it was never merged into the upstream
kernel. And we don't need any fops->fasync callback since the fcntl
implementation in the kernel already implements the noop case
correctly.

So stop this particular cargo-cult and rip it all out.

v2: Kill drm_fasync assignments in rcar (newly added) and imx drivers
(somehow I've missed that one in staging). Also drop the reference in
the drm DocBook. ARM compile-fail reported by Rob Clark.

v3: Move the removal of dev->buf_asnyc assignment in drm_setup to this
patch here.

v4: Actually git add ... tsk.

Cc: Dave Airlie <airlied@linux.ie>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Rob Clark <robdclark@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-08-19 10:05:17 +10:00
..
ABI Merge branch 'for-3.11/drivers' of git://git.kernel.dk/linux-block 2013-07-22 19:02:52 -07:00
accounting Documentation/accounting/getdelays.c: avoid strncpy in accounting tool 2013-07-03 16:08:06 -07:00
acpi Power management and ACPI updates for 3.11-rc1 2013-07-03 14:35:40 -07:00
aoe
arm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
arm64 arm64: KVM: document kernel object mappings in HYP 2013-06-12 16:42:20 +01:00
auxdisplay
backlight
blackfin
block
blockdev
bus-devices
cdrom
cgroups Merge branch 'for-3.11/core' of git://git.kernel.dk/linux-block 2013-07-11 13:03:24 -07:00
connector
console
cpu-freq
cpuidle
cris
crypto drivers/dma: remove unused support for MEMSET operations 2013-07-03 16:07:42 -07:00
development-process
device-mapper Add a device-mapper target called dm-switch to provide a multipath 2013-07-11 13:05:40 -07:00
devicetree ARM: SoC fixes for 3.11-rc 2013-07-26 12:42:40 -07:00
DocBook drm: remove FASYNC support 2013-08-19 10:05:17 +10:00
driver-model
dvb
early-userspace Documentation/early-userspace/README fix a typo 2013-06-05 16:24:58 +02:00
EDID
extcon
fault-injection
fb Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2013-07-09 16:04:31 -07:00
filesystems xfs: update (#2) for 3.11-rc1 2013-07-13 11:40:24 -07:00
firmware_class
fmc FMC: add a char-device mezzanine driver 2013-06-18 15:42:15 -07:00
frv
hid
hwmon New driver to support GMT G762/G763 pwm fan controllers 2013-07-03 19:56:35 -07:00
i2c Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2013-07-04 14:02:09 -07:00
i2o
ia64
ide
infiniband
input Input: MT - Specify that ABS_MT_SLOT must have a minimum of 0 2013-06-13 21:32:00 +02:00
ioctl s390/sclp: Add SCLP character device driver 2013-06-26 21:10:13 +02:00
isdn
ja_JP HOWTO ja_JP sync 2013-07-24 22:06:34 -07:00
kbuild Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2013-07-10 16:06:46 -07:00
kdump Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
ko_KR
laptops
leds
m68k
make
memory-devices
metag
mips
misc-devices
mmc
mn10300
mtd
namespaces
netlabel
networking Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-07-09 18:24:39 -07:00
nfc
parisc parisc: document the shadow registers 2013-07-09 22:09:19 +02:00
PCI
pcmcia
power Merge branch 'pm-assorted' 2013-06-28 13:01:40 +02:00
powerpc powerpc/perf: Core EBB support for 64-bit book3s 2013-07-01 11:50:10 +10:00
pps
prctl
pti
ptp
rapidio rapidio: documentation update 2013-07-03 16:08:05 -07:00
RCU Merge branches 'cbnum.2013.06.10a', 'doc.2013.06.10a', 'fixes.2013.06.10a', 'srcu.2013.06.10a' and 'tiny.2013.06.10a' into HEAD 2013-06-10 13:46:44 -07:00
s390
scheduler sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00
scsi [SCSI] megaraid_sas: Changelog and driver version update 2013-06-24 17:52:10 -07:00
security
serial
sh
sound ALSA: hda - Update HD-Audio-Models.txt 2013-06-17 11:16:33 +02:00
spi
sysctl net: rename busy poll socket op and globals 2013-07-10 17:08:27 -07:00
target
thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2013-07-11 12:26:08 -07:00
timers nohz_full: Document additional restrictions 2013-06-10 13:42:38 -07:00
trace The majority of the changes here are cleanups for the large changes that 2013-07-11 09:02:09 -07:00
usb Driver core patches for 3.11-rc1 2013-07-02 11:44:19 -07:00
vDSO
video4linux Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2013-07-13 12:09:57 -07:00
virtual Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
vm zswap: add documentation 2013-07-10 18:11:34 -07:00
w1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
watchdog watchdog: delete mpcore_wdt driver 2013-07-11 21:47:58 +02:00
wimax
x86 arm: add support for LZ4-compressed kernel 2013-07-09 10:33:30 -07:00
xtensa
zh_CN [media] v4l2-framework: replace g_chip_ident by g_std in the examples 2013-06-17 09:18:29 -03:00
.gitignore
00-INDEX FMC: add documentation for the core 2013-06-18 15:41:03 -07:00
applying-patches.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
bcache.txt Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes
circular-buffers.txt
clk.txt doc: clk: Fix incorrect wording 2013-06-10 23:54:14 +02:00
coccinelle.txt Coccinelle: Update information about the minimal version required 2013-07-03 22:58:20 +02:00
CodingStyle Documentation/CodingStyle: allow multiple return statements per function 2013-07-03 16:08:01 -07:00
cpu-hotplug.txt kernel: delete __cpuinit usage from all core kernel files 2013-07-14 19:36:59 -04:00
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt /dev/oldmem: Remove the interface 2013-07-03 16:08:03 -07:00
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt
dma-buf-sharing.txt
DMA-ISA-LPC.txt
dmaengine.txt
dmatest.txt dmatest: do not allow to interrupt ongoing tests 2013-06-08 02:13:44 +05:30
dontdiff
dynamic-debug-howto.txt
edac.txt
eisa.txt
email-clients.txt
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt
gpio.txt
highuid.txt
HOWTO
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
intel_txt.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt The majority of the changes here are cleanups for the large changes that 2013-07-11 09:02:09 -07:00
kernel-per-CPU-kthreads.txt Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
kmemcheck.txt
kmemleak.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
lockup-watchdogs.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
md.txt md: remove doubled description for sync_max, merging it within sync_min/sync_max 2013-07-03 09:43:28 +10:00
media-framework.txt Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2013-07-13 12:09:57 -07:00
memory-barriers.txt
memory-hotplug.txt
mono.txt
mutex-design.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
pi-futex.txt
pinctrl.txt Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-07-04 11:40:58 -07:00
pnp.txt
preempt-locking.txt
printk-formats.txt lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier 2013-07-01 23:22:13 -07:00
pwm.txt pwm: Add sysfs interface 2013-06-21 11:32:51 +02:00
ramoops.txt
rbtree.txt
remoteproc.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rt-mutex-design.txt sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00
rt-mutex.txt
rtc.txt rtc: add ability to push out an existing wakealarm using sysfs 2013-07-03 16:07:54 -07:00
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
spinlocks.txt sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00
stable_api_nonsense.txt
stable_kernel_rules.txt
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sysfs-rules.txt
sysrq.txt
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt vfio Updates for v3.11 2013-07-10 14:50:08 -07:00
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt
ww-mutex-design.txt mutex: Add support for wound/wait style locks 2013-06-26 12:10:56 +02:00
xz.txt
zorro.txt