Bunch of places in the code weren't using it where they could be -
this'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx
into a struct bvec_iter.
Signed-off-by: NKent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: "Ed L. Cashin" <ecashin@coraid.com>
CC: Nick Piggin <npiggin@kernel.dk>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Jim Paris <jim@jtan.com>
CC: Geoff Levand <geoff@infradead.org>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Neil Brown <neilb@suse.de>
CC: Steven Rostedt <rostedt@goodmis.org>
Acked-by: NEd Cashin <ecashin@coraid.com>

Just a little convenience macro - main reason to add it now is preparing
for immutable bio vecs, it'll reduce the size of the patch that puts
bi_sector/bi_size/bi_idx into a struct bvec_iter.
Signed-off-by: NKent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Lars Ellenberg <drbd-dev@lists.linbit.com>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Neil Brown <neilb@suse.de>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: Heiko Carstens <heiko.carstens@de.ibm.com>
CC: linux-s390@vger.kernel.org
CC: Chris Mason <chris.mason@fusionio.com>
CC: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: NSteven Whitehouse <swhiteho@redhat.com>

Signed-off-by: NKent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>
Acked-by: NNeilBrown <neilb@suse.de>

4740f73f "mfd: remove use of __devexit" removed the __devexit annotation
on the twl4030_madc_remove function, but left an __exit_p() present on the
pointer to this function. Using __exit_p was as wrong with the devexit in
place as it is now, but now we get a gcc warning about an unused function.

In order for the twl4030_madc_remove to work correctly in built-in code, we
have to remove the __exit_p.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

On LTC2978, only READ_TEMPERATURE is supported. It reports
the internal junction temperature. This register is unpaged.

On LTC3880, READ_TEMPERATURE and READ_TEMPERATURE2 are supported.
READ_TEMPERATURE is paged and reports external temperatures.
READ_TEMPERATURE2 is unpaged and reports the internal junction
temperature.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org # 3.2+
Acked-by: NJean Delvare <khali@linux-fr.org>

If krealloc() returns NULL, it *doesn't* free the original. So any code
of the form 'foo = krealloc(foo, …);' is almost certainly a bug.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Cc: stable@vger.kernel.org
Acked-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

idr_get_new*() and friends are about to be deprecated.  Convert to the
new idr_alloc() interface.

There are some peculiarities and possible bugs in the converted
functions.  This patch preserves those.

* drv_insert_node_res_element() returns -ENOMEM on alloc failure,
  -EFAULT if id space is exhausted.  -EFAULT is at best misleading.

* drv_proc_insert_strm_res_element() is even weirder.  It returns
  -EFAULT if kzalloc() fails, -ENOMEM if idr preloading fails and
  -EPERM if id space is exhausted.  What's going on here?

* drv_proc_insert_strm_res_element() doesn't free *pstrm_res after
  failure.

Only compile tested.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Víctor Manuel Jáquez Leal <vjaquez@igalia.com>
Cc: Rene Sapiens <rene.sapiens@ti.com>
Cc: Armando Uribe <x0095078@ti.com>
Cc: Omar Ramirez Luna <omar.ramirez@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

idr_get_new*() and friends are about to be deprecated.  Convert to the
new idr_alloc() interface.

Only compile tested.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 6a920060 ("IB/mlx4: convert to idr_alloc()") forgot to remove
idr_pre_get() call in mlx4_ib_cm_paravirt_init().  It's unnecessary and
idr_pre_get() will soon be deprecated.  Remove it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jack Morgenstein <jackm@dev.mellanox.co.il>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The commit 2e124b4a removed the checks
that prevented qt2_process_read_urb() from trying to put chars into
ttys that weren't actually opened.  This resulted in 'tty is NULL'
warnings from flush_to_ldisc() when the device was used.

The devices use just one read urb for all ports.  As a result
qt2_process_read_urb() may be called with the current port set to a
port number that has not been opened.  Add a check if the port is open
before calling tty_flip_buffer_push().
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Turns out we just need altsetting 1 and then we can talk to it.
Signed-off-by: NDan Williams <dcbw@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The buffer for responses must not overflow.
If this would happen, set a flag, drop the data and return
an error after user space has read all remaining data.
Signed-off-by: NOliver Neukum <oliver@neukum.org>
CC: stable@kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On Sat, Mar 02, 2013 at 10:45:10AM +0100, Sven Geggus wrote:
> This is the bad commit I found doing git bisect:
> 04f482fa is the first bad commit
> commit 04f482fa
> Author: Patrick McHardy <kaber@trash.net>
> Date:   Mon Mar 28 08:39:36 2011 +0000

Good job. I was too lazy to bisect for bad commit;)

Reading the code I found problematic kthread_should_stop call from netlink
connector which causes the oops. After applying a patch, I've been testing
owfs+w1 setup for nearly two days and it seems to work very reliable (no
hangs, no memleaks etc).
More detailed description and possible fix is given below:

Function w1_search can be called from either kthread or netlink callback.
While the former works fine, the latter causes oops due to kthread_should_stop
invocation.

This patch adds a check if w1_search is serving netlink command, skipping
kthread_should_stop invocation if so.
Signed-off-by: NMarcin Jurkowski <marcin1j@gmail.com>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Cc: Josh Boyer <jwboyer@gmail.com>
Tested-by: NSven Geggus <lists@fuchsschwanzdomain.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org> # 3.0+

Commit 8a1861d9 ("w1-gpio: Simplify & get rid of defines") removed the
compile guards from the device-tree id table, thereby generating a
warning when building without device-tree support.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 8a1861d9 ("w1-gpio: Simplify & get rid of defines") changed
(apparently unknowingly) the driver to a hotpluggable platform-device
driver but did not not update the section markers for probe and remove
(to __devinit/exit, which have since been removed). A later commit fixed
the section mismatch for probe, but left remove marked with __exit.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Cc: stable <stable@vger.kernel.org> # 3.8
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The Rigblaster Advantage is an amateur radio interface sold by West Mountain
Radio. It contains a cp210x serial interface but the device ID is not in
the driver.
Signed-off-by: NSteve Conklin <sconklin@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The Kconfig symbol SERIAL_S3C2412 got removed in commit
da121506 ("serial: samsung: merge
probe() function from all SoC specific extensions"). But it also added a
last reference to that symbol. The commit and the tree make clear that
CPU_S3C2412 should have been used instead.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

With commit 835d844d (8250_pnp: do pnp probe before legacy probe), the
8250 driver was renamed to 8250_core.  This means any existing usage of
the 8259.<xxxx> module parameters or as a kernel command line switch is
now broken, as the 8250_core driver doesn't parse options belonging to
something called "8250".

To solve this, we redefine the module options in a dummy function using
a redefined MODULE_PARAM_PREFX when built into the kernel.  In the case
where we're building as a module, we provide an alias to the old 8250
name.  The dummy function prevents compiler errors due to global variable
redefinitions that happen as part of the module_param_ macro expansions.
Signed-off-by: NJosh Boyer <jwboyer@redhat.com>
Acked-by: NJiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This could have been either ARCH_S5P64X0 or CPU_S5P6450. Looking at
commit 2555e663 ("ARM: S5P64X0: Add UART
serial support for S5P6450") - which added this typo - makes clear this
should be CPU_S5P6450.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Acked-by: NKukjin Kim <kgene.kim@samsung.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The InsydeH2O BIOS (version dated 09/12/2011) has the following in
its pnp resouces for its serial ports:

$ cat /sys/bus/pnp/devices/00:0b/resources
state = active
io disabled
irq disabled

We do not check if the resources are disabled, and create a bogus
ttyS* device. Since commit 835d844d (8250_pnp: do pnp probe
before legacy probe) we get a bogus ttyS0, which prevents the legacy
probe from detecting it.

Note, the BIOS can also be upgraded, fixing this problem, but for people
who can't do that, this fix is needed.
Reported-by: NVincent Deffontaines <vincent@gryzor.com>
Tested-by: NVincent Deffontaines <vincent@gryzor.com>
Signed-off-by: NSean Young <sean@mess.org>
Cc: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

92a19f9c introduced a local variable
with the same name as the argument to bcm_uart_do_rx, breaking
compilation. Fix this by renaming the new variable and its uses where
expected.
Signed-off-by: NJonas Gorski <jogo@openwrt.org>
Acked-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

01:08.0 Communication controller: NetMos Technology PCI 9835 Multi-I/O Controller (rev 01)
	Subsystem: Device [1000:0012]
	Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Interrupt: pin A routed to IRQ 20
	Region 0: I/O ports at e050 [size=8]
	Region 1: I/O ports at e040 [size=8]
	Region 2: I/O ports at e030 [size=8]
	Region 3: I/O ports at e020 [size=8]
	Region 4: I/O ports at e010 [size=8]
	Region 5: I/O ports at e000 [size=16]
Signed-off-by: NWang YanQing <udknight@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

I've managed to find an 8 port version of the card 4 port card which was discussed here:

http://marc.info/?l=linux-serial&m=120760744205314&w=2

Looking back at that thread there were two issues in the original patch.

1) The I/O ports for the UARTs are within BAR2 not BAR0. This can been seen in the original post.
2) A serial quirk isn't needed as these cards have no memory in BAR0 which makes pci_plx9050_init just return.

This patch fixes the 4 port support to use BAR2, removes the bogus quirk and adds support for the 8 port card.

$ lspci -vvv -n -s 00:08.0
00:08.0 0780: 10b5:9050 (rev 01)
	Subsystem: 10b5:1588
	Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Interrupt: pin A routed to IRQ 17
	Region 1: I/O ports at ff00 [size=128]
	Region 2: I/O ports at fe00 [size=64]
	Region 3: I/O ports at fd00 [size=8]
	Capabilities: <access denied>
	Kernel driver in use: serial

$ dmesg | grep 0000:00:08.0:
[    0.083320] pci 0000:00:08.0: [10b5:9050] type 0 class 0x000780
[    0.083355] pci 0000:00:08.0: reg 14: [io  0xff00-0xff7f]
[    0.083369] pci 0000:00:08.0: reg 18: [io  0xfe00-0xfe3f]
[    0.083382] pci 0000:00:08.0: reg 1c: [io  0xfd00-0xfd07]
[    0.083460] pci 0000:00:08.0: PME# supported from D0 D3hot
[    1.212867] 0000:00:08.0: ttyS4 at I/O 0xfe00 (irq = 17) is a 16550A
[    1.233073] 0000:00:08.0: ttyS5 at I/O 0xfe08 (irq = 17) is a 16550A
[    1.253270] 0000:00:08.0: ttyS6 at I/O 0xfe10 (irq = 17) is a 16550A
[    1.273468] 0000:00:08.0: ttyS7 at I/O 0xfe18 (irq = 17) is a 16550A
[    1.293666] 0000:00:08.0: ttyS8 at I/O 0xfe20 (irq = 17) is a 16550A
[    1.313863] 0000:00:08.0: ttyS9 at I/O 0xfe28 (irq = 17) is a 16550A
[    1.334061] 0000:00:08.0: ttyS10 at I/O 0xfe30 (irq = 17) is a 16550A
[    1.354258] 0000:00:08.0: ttyS11 at I/O 0xfe38 (irq = 17) is a 16550A
Signed-off-by: NScott Ashcroft <scott.ashcroft@talk21.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for Altera 8250/16550 compatible serial port.
Signed-off-by: NLey Foon Tan <lftan@altera.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove the extra code left over when the serial driver was changed
to require a clock. There is no fallback to 24Mhz as a clock is
now required.

Also remove a second call to of_clk_get which is unnecessary.
Signed-off-by: NTony Prisk <linux@prisktech.co.nz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

mpc512x platform clock code names PSC clocks as "pscX_mclk" but
the driver tries to get "pscX_clk" clock and this results in
errors like:

  mpc52xx-psc-uart 80011700.psc: Failed to get PSC clock entry!

The problem appears when opening ttyPSC devices other than the
system's serial console. Since getting and enabling the PSC clock
fails, uart port startup doesn't succeed and tty flag TTY_IO_ERROR
remains set causing further errors in tty ioctls, i.e.
'strace stty -F /dev/ttyPSC1' shows:

open("/dev/ttyPSC1", O_RDONLY|O_NONBLOCK|O_LARGEFILE) = 3
dup2(3, 0)                              = 0
close(3)                                = 0
fcntl64(0, F_GETFL)                     = 0x10800 (flags O_RDONLY|O_NONBLOCK|O_LARGEFILE)
fcntl64(0, F_SETFL, O_RDONLY|O_LARGEFILE) = 0
ioctl(0, TCGETS, 0xbff89038)            = -1 EIO (Input/output error)

Only request PSC clock names that the platform actually provides.
Signed-off-by: NAnatolij Gustschin <agust@denx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since commit c8801a8e
"regulator: core: Mark all get and enable calls as __must_check",
we must check return value of regulator_enable() to silence below build warning.

  CC      drivers/mfd/ab8500-gpadc.o
drivers/mfd/ab8500-gpadc.c: In function 'ab8500_gpadc_runtime_resume':
drivers/mfd/ab8500-gpadc.c:598:18: warning: ignoring return value of 'regulator_enable', declared with attribute warn_unused_result [-Wunused-result]
drivers/mfd/ab8500-gpadc.c: In function 'ab8500_gpadc_probe':
drivers/mfd/ab8500-gpadc.c:655:18: warning: ignoring return value of 'regulator_enable', declared with attribute warn_unused_result [-Wunused-result]

Also convert to devm_regulator_get(), this fixes a missing regulator_put() call
in ab8500_gpadc_remove().
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Looks like the conversion to enum was missed for the definition of this
function, the declaration has been updated.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Clean up interrupts on exit, silencing a sparse warning caused by
tps65912_irq_exit() being defined but not prototyped as we go.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Currently driver sets the irq type to IRQF_TRIGGER_LOW which is
causing interrupt registration failure in ARM based SoCs as:
[    0.208479] genirq: Setting trigger mode 8 for irq 118 failed (gic_set_type+0x0/0xf0)
[    0.208513] dummy 0-0059: Failed to request IRQ 118: -22

Provide the irq flags through platform data if device is registered
through board file or get the irq type from DT node property in place
of hardcoding the irq flag in driver to support multiple platforms.

Also configure the device to generate the interrupt signal according to
flag type.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This patch fixes below build error when CONFIG_POWER_SUPPLY is not set.

drivers/built-in.o: In function `ab8500_power_off':
drivers/mfd/ab8500-sysctrl.c:37: undefined reference to `power_supply_get_by_name'
drivers/mfd/ab8500-sysctrl.c:53: undefined reference to `power_supply_get_by_name'
make: *** [vmlinux] Error 1
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The helper functions omap_usbhs_rev1_hostconfig()
and omap_usbhs_rev2_hostconfig() don't write into
the hostconfig register. Make sure that we write
the return value into the hostconfig register.
Signed-off-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

4 ports; AT/PPP is standard CDC-ACM.  The other three (added by this
patch) are QCDM/DIAG, possibly GPS, and unknown.
Signed-off-by: NDan Williams <dcbw@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

when making commit e574d570 (usb: musb: fix
compile warning) I forgot to git add this
part of the patch which ended up introducing
a possible build error.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It's redundant since linux/acpi.h has include it when CONFIG_ACPI enabled,
and when CONFIG_ACPI disabled it will trigger compiling warning

In file included from drivers/xen/xen-stub.c:28:0:
include/acpi/acpi_drivers.h:103:31:
warning: 'struct acpi_device' declared inside parameter list [enabled by default]
include/acpi/acpi_drivers.h:103:31:
warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
include/acpi/acpi_drivers.h:107:43:
warning: 'struct acpi_pci_root' declared inside parameter list [enabled by default]
Reported-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NLiu Jinsong <jinsong.liu@intel.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

As pointed out by Dan Carpenper in
<http://driverdev.linuxdriverproject.org/pipermail/devel/2013-February/036025.html>,
the dt9812 comedi driver's use of the `chanspec` member of `struct
comedi_insn` as a channel number is incorrect.  Change it to use
`CR_CHAN(insn->chanspec)` as the channel number (where `insn` is a
pointer to the `struct comedi_insn` being processed).
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org> # 3.8 onwards
Cc: Anders Blomdell <anders.blomdell@control.lth.se>
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vt6656/card.c: In function ‘CARDqGetNextTBTT’:
drivers/staging/vt6656/card.c:793: warning: integer constant is too large for ‘unsigned long’ type

Commit c7b7cad0 ("staging/vt6656: Fix
sparse warning constant 0xffffffff00000000U is so big it is unsigned long")
changed the constant to "0xffffffff00000000UL", but that only works on
64-bit.  Change it "0xffffffff00000000ULL" to fix it for 32-bit, too.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: NPeter Huewe <peterhuewe@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes an instance of DMA buffer on stack(being passed to
usb_control_msg)for the USB-DUXsigma Board driver. Found using smatch.
Signed-off-by: NKumar Amit Mehta <gmate.amit@gmail.com>
Reviewed-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If the bootloader already enabled the display, the interrupt handler
will be called as soon as it is registered. If the CRTC is not already
added at this time, the call to imx_drm_handle_vblank will result in
a NULL pointer dereference.

The patch fixes a kernel panic [1], which has been on linux-next since
Jan 8 [2].

[1] http://thread.gmane.org/gmane.linux.ports.arm.kernel/218858
[2] http://thread.gmane.org/gmane.linux.ports.arm.kernel/208192Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>