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602004 Commits (700ca8c04a0f4402f379055eec97351e0d6c0087)

Author SHA1 Message Date
Robin Murphy db413b51c0 arm64: Remove orphaned __addr_ok() definition
Since commit 12a0ef7b0a ("arm64: use generic strnlen_user and
strncpy_from_user functions"), the definition of __addr_ok() has been
languishing unused; eradicate the sucker.

CC: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-31 13:11:11 +01:00
Thomas Huth 8dd75ccb57 powerpc: Use privileged SPR number for MMCR2
We are already using the privileged versions of MMCR0, MMCR1
and MMCRA in the kernel, so for MMCR2, we should better use
the privileged versions, too, to be consistent.

Fixes: 240686c136 ("powerpc: Initialise PMU related regs on Power8")
Cc: stable@vger.kernel.org # v3.10+
Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-31 20:08:32 +10:00
Thomas Huth d23fac2b27 powerpc: Fix definition of SIAR and SDAR registers
The SIAR and SDAR registers are available twice, one time as SPRs
780 / 781 (unprivileged, but read-only), and one time as the SPRs
796 / 797 (privileged, but read and write). The Linux kernel code
currently uses the unprivileged  SPRs - while this is OK for reading,
writing to that register of course does not work.
Since the KVM code tries to write to this register, too (see the mtspr
in book3s_hv_rmhandlers.S), the contents of this register sometimes get
lost for the guests, e.g. during migration of a VM.
To fix this issue, simply switch to the privileged SPR numbers instead.

Cc: stable@vger.kernel.org
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-31 20:07:56 +10:00
Will Deacon ab2e1b8923 Revert "arm64: hugetlb: partial revert of 66b3923a1a0f"
This reverts commit ff7925848b.

Now that the contiguous-hint hugetlb regression has been debugged and
fixed upstream by 66ee95d16a ("mm: exclude HugeTLB pages from THP
page_mapped() logic"), we can revert the previous partial revert of this
feature.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-31 11:00:09 +01:00
hongkun.cao 5edf673d07 pinctrl: mediatek: fix dual-edge code defect
When a dual-edge irq is triggered, an incorrect irq will be reported on
condition that the external signal is not stable and this incorrect irq
has been registered.
Correct the register offset.

Cc: stable@vger.kernel.org
Signed-off-by: Hongkun Cao <hongkun.cao@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-31 10:13:45 +02:00
Arnd Bergmann d0196c8d5d drm/omap: include gpio/consumer.h where needed
A lot of the display drivers for OMAP use the gpio descriptor functions
that are only available in linux/gpio.h if GPIOLIB is enabled and
otherwise produce a build error:

drivers/gpu/drm/omapdrm/displays/encoder-opa362.c: In function 'opa362_enable':
drivers/gpu/drm/omapdrm/displays/encoder-opa362.c:101:3: error: implicit declaration of function 'gpiod_set_value_cansleep' [-Werror=implicit-function-declaration]
drivers/gpu/drm/omapdrm/displays/panel-dpi.c: In function 'panel_dpi_probe_pdata':
drivers/gpu/drm/omapdrm/displays/panel-dpi.c:189:23: error: implicit declaration of function 'gpio_to_desc' [-Werror=implicit-function-declaration]
drivers/gpu/drm/omapdrm/displays/panel-sharp-ls037v7dw01.c: In function 'sharp_ls_enable':
drivers/gpu/drm/omapdrm/displays/panel-sharp-ls037v7dw01.c:120:3: error: implicit declaration of function 'gpiod_set_value_cansleep' [-Werror=implicit-function-declaration]

This replaces the existing linux/gpio.h with linux/gpio/consumer.h
where needed. In case of panel-lgphilips-lb035q02.c however, we
also have to include linux/gpio.h to get the definition of gpio_is_valid
and gpio_set_value_cansleep that are used for the non-DT case.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[tomi.valkeinen@ti.com: resolved conflicts]
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:30:14 +03:00
Arnd Bergmann 2d8024534a drm/omap: include linux/seq_file.h where needed
The omapdrm driver relies on this header to be included
implicitly, but this does not always work, and I get
this error in randconfig builds:

gpu/drm/omapdrm/dss/hdmi_phy.c: In function 'hdmi_phy_dump':
gpu/drm/omapdrm/dss/hdmi_phy.c:34:2: error: implicit declaration of function 'seq_printf' [-Werror=implicit-function-declaration]
gpu/drm/omapdrm/dss/hdmi_wp.c: In function 'hdmi_wp_dump':
gpu/drm/omapdrm/dss/hdmi_wp.c:26:2: error: implicit declaration of function 'seq_printf' [-Werror=implicit-function-declaration]
gpu/drm/omapdrm/dss/hdmi_pll.c: In function 'hdmi_pll_dump':
gpu/drm/omapdrm/dss/hdmi_pll.c:30:2: error: implicit declaration of function 'seq_printf' [-Werror=implicit-function-declaration]

This adds the #include statements in all files that have
a seq_printf statement.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:30:14 +03:00
Peter Ujfalusi 62cb0751c8 Revert "drm/omap: no need to select OMAP2_DSS"
This reverts commit 1c278e5e37.

If DRM_OMAP does not select OMAP2_DSS it is possible to build a kernel with
DRM_OMAP only and not selecting OMAP2_DSS. Since omapdrm depends on
OMAP2_DSS this will result on broken kernel build.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:30:14 +03:00
Peter Ujfalusi 973999aa01 drm/omap: Remove regulator API abuse
regulator_can_change_voltage() is deprecated and it's use is not necessary
as commit:
6a0028b3dd regulator: Deprecate regulator_can_change_voltage()
describers it clearly.

Also, regulator_set_voltage() is misused in the driver, as it is
supposed to be used only in cases where the regulator voltage needs to
be changed dynamically at runtime. In DSS's case, we always want a fixed
voltage, set in the .dts files.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:28:31 +03:00
Jim Lodes 4bafcbc77f OMAPDSS: HDMI5: Change DDC timings
The DDC scl high and low times were set to the minimum values
from the i2c specification, but the i2c specification takes into
account the rise time and fall time to calculate the frequency.
To pass HDMI certification DDC can not exceed 100kHz therefore in
a system where the rise times and fall times are negligible the high
and low times for scl need to be 10us.

Signed-off-by: Jim Lodes <jim.lodes@garmin.com>
Signed-off-by: J.D. Schroeder <jay.schroeder@garmin.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:20:43 +03:00
Jim Lodes 08f707ac3e OMAPDSS: HDMI5: Fix AVI infoframe
The AVI infoframe R0-R3 in the 2nd data byte represents the
Active Format Aspect Ratio. It is four bits long not two bits.
This fixes that mask used to extract the bits before writing the
bits to the hardware registers.

Signed-off-by: Jim Lodes <jim.lodes@garmin.com>
Signed-off-by: J.D. Schroeder <jay.schroeder@garmin.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:20:42 +03:00
Tomi Valkeinen 91cd220aad drm/omap: fix OMAP4 hdmi_core_powerdown_disable()
hdmi_core_powerdown_disable() is supposed to disable HDMI core's
power-down mode. However, the function sets the power-down bit to 0,
which means "enable power-down".

This hasn't caused any issues as the PD seems to affect only interrupts
from HDMI core, and none of those interrupts are used at the moment. CEC
functionality requires core interrupts, and the PD mode needs to be
fixed.

This patch fixes hdmi_core_powerdown_disable() to actually disable the
PD mode.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
2016-05-31 08:20:42 +03:00
Tomi Valkeinen d9e32ecda4 drm/omap: Fix missing includes
With certain kernel config options many omapdrm files fail to compile
due to missing include of linux/gpio/consumer.h and linux/of.h.

This patch adds those includes.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reported-by: Dan Murphy <dmurphy@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2016-05-31 08:20:42 +03:00
Arnd Bergmann 2639d6b9be drm/omapdrm: include pinctrl/consumer.h where needed
In some configurations, we can build the OMAP dss driver without
implictly including the pinctrl consumer definitions, causing
a build error:

gpu/drm/omapdrm/dss/dss.c: In function 'dss_runtime_suspend':
gpu/drm/omapdrm/dss/dss.c:1268:2: error: implicit declaration of function 'pinctrl_pm_select_sleep_state' [-Werror=implicit-function-declaration]

This adds an explicit #include.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-05-31 08:20:42 +03:00
Filipe Manana b5de8d0df8 Btrfs: fix race between device replace and read repair
While we are finishing a device replace operation we can have a concurrent
task trying to do a read repair operation, in which case it will call
btrfs_map_block() to get a struct btrfs_bio which can have a stripe that
points to the source device of the device replace operation. This allows
for the read repair task to dereference the stripe's device pointer after
the device replace operation has freed the source device, resulting in
an invalid memory access. This is similar to the problem solved by my
previous patch in the same series and named "Btrfs: fix race between
device replace and discard".

So fix this by surrounding the call to btrfs_map_block() and the code
that uses the returned struct btrfs_bio with calls to
btrfs_bio_counter_inc_blocked() and btrfs_bio_counter_dec(), giving the
proper serialization with the finishing phase of the device replace
operation.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-31 01:00:03 +01:00
Filipe Manana 2999241daa Btrfs: fix race between device replace and discard
While we are finishing a device replace operation, we can make a discard
operation (fs mounted with -o discard) do an invalid memory access like
the one reported by the following trace:

[ 3206.384654] general protection fault: 0000 [#1] PREEMPT SMP
[ 3206.387520] Modules linked in: dm_mod btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis psmouse tpm ppdev sg parport_pc evdev i2c_piix4 parport
processor serio_raw i2c_core pcspkr button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom ata_generic sd_mod virtio_scsi ata_piix libata virtio_pci
virtio_ring scsi_mod e1000 virtio floppy [last unloaded: btrfs]
[ 3206.388595] CPU: 14 PID: 29194 Comm: fsstress Not tainted 4.6.0-rc7-btrfs-next-29+ #1
[ 3206.388595] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[ 3206.388595] task: ffff88017ace0100 ti: ffff880171b98000 task.ti: ffff880171b98000
[ 3206.388595] RIP: 0010:[<ffffffff8124d233>]  [<ffffffff8124d233>] blkdev_issue_discard+0x5c/0x2a7
[ 3206.388595] RSP: 0018:ffff880171b9bb80  EFLAGS: 00010246
[ 3206.388595] RAX: ffff880171b9bc28 RBX: 000000000090d000 RCX: 0000000000000000
[ 3206.388595] RDX: ffffffff82fa1b48 RSI: ffffffff8179f46c RDI: ffffffff82fa1b48
[ 3206.388595] RBP: ffff880171b9bcc0 R08: 0000000000000000 R09: 0000000000000001
[ 3206.388595] R10: ffff880171b9bce0 R11: 000000000090f000 R12: ffff880171b9bbe8
[ 3206.388595] R13: 0000000000000010 R14: 0000000000004868 R15: 6b6b6b6b6b6b6b6b
[ 3206.388595] FS:  00007f6182e4e700(0000) GS:ffff88023fdc0000(0000) knlGS:0000000000000000
[ 3206.388595] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3206.388595] CR2: 00007f617c2bbb18 CR3: 000000017ad9c000 CR4: 00000000000006e0
[ 3206.388595] Stack:
[ 3206.388595]  0000000000004878 0000000000000000 0000000002400040 0000000000000000
[ 3206.388595]  0000000000000000 ffff880171b9bbe8 ffff880171b9bbb0 ffff880171b9bbb0
[ 3206.388595]  ffff880171b9bbc0 ffff880171b9bbc0 ffff880171b9bbd0 ffff880171b9bbd0
[ 3206.388595] Call Trace:
[ 3206.388595]  [<ffffffffa042899e>] btrfs_issue_discard+0x12f/0x143 [btrfs]
[ 3206.388595]  [<ffffffffa042899e>] ? btrfs_issue_discard+0x12f/0x143 [btrfs]
[ 3206.388595]  [<ffffffffa042e862>] btrfs_discard_extent+0x87/0xde [btrfs]
[ 3206.388595]  [<ffffffffa04303b5>] btrfs_finish_extent_commit+0xb2/0x1df [btrfs]
[ 3206.388595]  [<ffffffff8149c246>] ? __mutex_unlock_slowpath+0x150/0x15b
[ 3206.388595]  [<ffffffffa04464c4>] btrfs_commit_transaction+0x7fc/0x980 [btrfs]
[ 3206.388595]  [<ffffffff8149c246>] ? __mutex_unlock_slowpath+0x150/0x15b
[ 3206.388595]  [<ffffffffa0459af6>] btrfs_sync_file+0x38f/0x428 [btrfs]
[ 3206.388595]  [<ffffffff811a8292>] vfs_fsync_range+0x8c/0x9e
[ 3206.388595]  [<ffffffff811a82c0>] vfs_fsync+0x1c/0x1e
[ 3206.388595]  [<ffffffff811a8417>] do_fsync+0x31/0x4a
[ 3206.388595]  [<ffffffff811a8637>] SyS_fsync+0x10/0x14
[ 3206.388595]  [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8
[ 3206.388595]  [<ffffffff81100c6b>] ? time_hardirqs_off+0x9/0x14
[ 3206.388595]  [<ffffffff8108e87d>] ? trace_hardirqs_off_caller+0x1f/0xaa

This happens because when we call btrfs_map_block() from
btrfs_discard_extent() to get a btrfs_bio structure, the device replace
operation has not finished yet, but before we use the device of one of the
stripes from the returned btrfs_bio structure, the device object is freed.

This is illustrated by the following diagram.

            CPU 1                                                  CPU 2

 btrfs_dev_replace_start()

 (...)

 btrfs_dev_replace_finishing()

   btrfs_start_transaction()
   btrfs_commit_transaction()

   (...)

                                                            btrfs_sync_file()
                                                              btrfs_start_transaction()

                                                              (...)

                                                              btrfs_commit_transaction()
                                                                btrfs_finish_extent_commit()
                                                                  btrfs_discard_extent()
                                                                    btrfs_map_block()
                                                                      --> returns a struct btrfs_bio
                                                                          with a stripe that has a
                                                                          device field pointing to
                                                                          source device of the replace
                                                                          operation (the device that
                                                                          is being replaced)

   mutex_lock(&uuid_mutex)
   mutex_lock(&fs_info->fs_devices->device_list_mutex)
   mutex_lock(&fs_info->chunk_mutex)

   btrfs_dev_replace_update_device_in_mapping_tree()
     --> iterates the mapping tree and for each
         extent map that has a stripe pointing to
         the source device, it updates the stripe
         to point to the target device instead

   btrfs_rm_dev_replace_blocked()
     --> waits for fs_info->bio_counter to go down to 0

   btrfs_rm_dev_replace_remove_srcdev()
     --> removes source device from the list of devices

   mutex_unlock(&fs_info->chunk_mutex)
   mutex_unlock(&fs_info->fs_devices->device_list_mutex)
   mutex_unlock(&uuid_mutex)

   btrfs_rm_dev_replace_free_srcdev()
     --> frees the source device

                                                                    --> iterates over all stripes
                                                                        of the returned struct
                                                                        btrfs_bio
                                                                    --> for each stripe it
                                                                        dereferences its device
                                                                        pointer
                                                                        --> it ends up finding a
                                                                            pointer to the device
                                                                            used as the source
                                                                            device for the replace
                                                                            operation and that was
                                                                            already freed

So fix this by surrounding the call to btrfs_map_block(), and the code
that uses the returned struct btrfs_bio, with calls to
btrfs_bio_counter_inc_blocked() and btrfs_bio_counter_dec(), so that
the finishing phase of the device replace operation blocks until the
the bio counter decreases to zero before it frees the source device.
This is the same approach we do at btrfs_map_bio() for example.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-31 00:59:44 +01:00
Linus Torvalds 852f42a69b Merge branch 'uuid' (lib/uuid fixes from Andy)
Merge lib/uuid fixes from Andy Shevchenko.

* emailed patches from Andy Shevchenko <andriy.shevchenko@linux.intel.com>:
  lib/uuid.c: use correct offset in uuid parser
  lib/uuid: add a test module
2016-05-30 15:27:07 -07:00
Bjørn Mork bc9dc9d5ee lib/uuid.c: use correct offset in uuid parser
Use '+ 0' and '+ 1' as offsets, like they were intended, instead of
adding to the result.

Fixes: 2b1b0d6670 ("lib/uuid.c: introduce a few more generic helpers")
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-30 15:26:57 -07:00
Andy Shevchenko cfaff0e515 lib/uuid: add a test module
It appears that somehow I missed a test of the latest UUID rework which
landed in the kernel.  Present a small test module to avoid such cases
in the future.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-30 15:26:57 -07:00
Linus Torvalds 446985428d Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - missing selection in public_key that may result in a build failure

   - Potential crash in error path in omap-sham

   - ccp AES XTS bug that affects requests larger than 4096"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: ccp - Fix AES XTS error for request sizes above 4096
  crypto: public_key: select CRYPTO_AKCIPHER
  crypto: omap-sham - potential Oops on error in probe
2016-05-30 15:20:18 -07:00
Ilya Dryomov 4a3262b17c libceph: use %s instead of %pE in dout()s
Commit d30291b985 ("libceph: variable-sized ceph_object_id") changed
dout()s in what is now encode_request() and ceph_object_locator_to_pg()
to use %pE, mostly to document that, although all rbd and cephfs object
names are NULL-terminated strings, ceph_object_id will handle any RADOS
object name, including the one containing NULs, just fine.

However, it turns out that vbin_printf() can't handle anything but ints
and %s - all %p suffixes are ignored.  The buffer %p** points to isn't
recorded, resulting in trash in the messages if the buffer had been
reused by the time bstr_printf() got to it.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2016-05-30 23:00:23 +02:00
Ilya Dryomov dc045a9168 libceph: put request only if it's done in handle_reply()
handle_reply() may be called twice on the same request: on ack and then
on commit.  This occurs on btrfs-formatted OSDs or if cephfs sync write
path is triggered - CEPH_OSD_FLAG_ACK | CEPH_OSD_FLAG_ONDISK.

handle_reply() handles this with the help of done_request().

Fixes: 5aea3dcd50 ("libceph: a major OSD client update")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2016-05-30 23:00:23 +02:00
Ilya Dryomov b7ec35b304 libceph: change ceph_osdmap_flag() to take osdc
For the benefit of every single caller, take osdc instead of map.
Also, now that osdc->osdmap can't ever be NULL, drop the check.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2016-05-30 23:00:22 +02:00
Linus Walleij 545ebd9a9b gpio: drop lock before reading GPIO direction
When adding the gpiochip, the GPIO HW drivers' callback get_direction()
could get called in atomic context. Some of the GPIO HW drivers may
sleep when accessing the register.

Move the lock before initializing the descriptors.

Reported-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 17:11:59 +02:00
Linus Walleij 54d77198fd gpio: bail out silently on NULL descriptors
In fdeb8e1547
("gpio: reflect base and ngpio into gpio_device")
assumed that GPIO descriptors are either valid or error
pointers, but gpiod_get_[index_]optional() actually return
NULL descriptors and then all subsequent calls should just
bail out.

Cc: stable@vger.kernel.org
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Fixes: fdeb8e1547 ("gpio: reflect base and ngpio into gpio_device")
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 16:56:41 +02:00
Linus Walleij 8b92e17efe gpio: handle compatible ioctl() pointers
If we're using the compatible ioctl() we need to handle the
argument pointer in a special way or there will be trouble.

Fixes: 3c702e9987 ("gpio: add a userspace chardev ABI for GPIOs")
Reported-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 16:00:31 +02:00
Alex Williamson 089f1c6b2d vfio/type1: Fix build warning
This function cannot actually be called with npage = 0, so in practice
this doesn't return an uninitialized value.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-30 07:58:10 -06:00
Alex Williamson 956b56a984 vfio/pci: Fix ordering of eventfd vs virqfd shutdown
Both the INTx and MSI/X disable paths do an eventfd_ctx_put() for the
trigger eventfd before calling vfio_virqfd_disable() any potential
mask and unmask eventfds.  This opens a use-after-free race where an
inopportune irqfd can reference the freed signalling eventfd.  Reorder
to avoid this possibility.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-30 07:50:10 -06:00
Srinivas Pandruvada 6cacd115a8 cpufreq: intel_pstate: Downgrade print level for _PPC
Downgrade pr_info to pr_debug for the "_PPC limits will be enforced"
message.

In server systems with many cores this message is annoying.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-30 15:22:02 +02:00
Filipe Manana 22ab04e814 Btrfs: fix race between device replace and chunk allocation
While iterating and copying extents from the source device, the device
replace code keeps adjusting a left cursor that is used to make sure that
once we finish processing a device extent, any future writes to extents
from the corresponding block group will get into both the source and
target devices. This left cursor is also used for resuming the device
replace operation at mount time.

However using this left cursor to decide whether writes go into both
devices or only the source device is not enough to guarantee we don't
miss copying extents into the target device. There are two cases where
the current approach fails. The first one is related to when there are
holes in the device and they get allocated for new block groups while
the device replace operation is iterating the device extents (more on
this explained below). The second one is that when that loop over the
device extents finishes, we start dellaloc, wait for all ordered extents
and then commit the current transaction, we might have got new block
groups allocated that are now using a device extent that has an offset
greater then or equals to the value of the left cursor, in which case
writes to extents belonging to these new block groups will get issued
only to the source device.

For the first case where the current approach of using a left cursor
fails, consider the source device currently has the following layout:

  [ extent bg A ] [ hole, unallocated space ] [extent bg B ]
  3Gb             4Gb                         5Gb

While we are iterating the device extents from the source device using
the commit root of the device tree, the following happens:

        CPU 1                                            CPU 2

                      <we are at transaction N>

  scrub_enumerate_chunks()
    --> searches the device tree for
        extents belonging to the source
        device using the device tree's
        commit root
    --> 1st iteration finds extent belonging to
        block group A

        --> sets block group A to RO mode
            (btrfs_inc_block_group_ro)

        --> sets cursor left to found_key.offset
            which is 3Gb

        --> scrub_chunk() starts
            copies all allocated extents from
            block group's A stripe at source
            device into target device

                                                           btrfs_alloc_chunk()
                                                             --> allocates device extent
                                                                 in the range [4Gb, 5Gb[
                                                                 from the source device for
                                                                 a new block group C

                                                           extent allocated from block
                                                           group C for a direct IO,
                                                           buffered write or btree node/leaf

                                                           extent is written to, perhaps
                                                           in response to a writepages()
                                                           call from the VM or directly
                                                           through direct IO

                                                           the write is made only against
                                                           the source device and not against
                                                           the target device because the
                                                           extent's offset is in the interval
                                                           [4Gb, 5Gb[ which is larger then
                                                           the value of cursor_left (3Gb)

        --> scrub_chunks() finishes

        --> updates left cursor from 3Gb to
            4Gb

        --> btrfs_dec_block_group_ro() sets
            block group A back to RW mode

                             <we are still at transaction N>

    --> 2nd iteration finds extent belonging to
        block group B - it did not find the new
        extent in the range [4Gb, 5Gb[ for block
        group C because we are using the device
        tree's commit root or even because the
        block group's items are not all yet
        inserted in the respective btrees, that is,
        the block group is still attached to some
        transaction handle's new_bgs list and
        btrfs_create_pending_block_groups() was
        not called yet against that transaction
        handle, so the device extent items were
        not yet inserted into the devices tree

                             <we are still at transaction N>

        --> so we end not copying anything from the newly
            allocated device extent from the source device
            to the target device

So fix this by making __btrfs_map_block() always redirect writes to the
target device as well, independently of the left cursor's value. With
this change the left cursor is now used only for the purpose of tracking
progress and allow a mount operation to resume a device replace.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30 12:58:26 +01:00
Filipe Manana 1a1a8b732c Btrfs: fix race setting block group back to RW mode during device replace
After it finishes processing a device extent, the device replace code sets
back the block group to RW mode and then after that it sets the left cursor
to match the logical end address of the block group, so that future writes
into extents belonging to the block group go both the source (old) and
target (new) devices. However from the moment we turn the block group
back to RW mode we have a short time window, that lasts until we update
the left cursor's value, where extents can be allocated from the block
group and written to, in which case they will not be copied/written to
the target (new) device. Fix this by updating the left cursor's value
before turning the block group back to RW mode.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30 12:58:24 +01:00
Filipe Manana 81e87a736c Btrfs: fix unprotected assignment of the left cursor for device replace
We were assigning new values to fields of the device replace object
without holding the respective lock after processing each device extent.
This is important for the left cursor field which can be accessed by a
concurrent task running __btrfs_map_block (which, correctly, takes the
device replace lock).
So change these fields while holding the device replace lock.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30 12:58:23 +01:00
Filipe Manana f0e9b7d640 Btrfs: fix race setting block group readonly during device replace
When we do a device replace, for each device extent we find from the
source device, we set the corresponding block group to readonly mode to
prevent writes into it from happening while we are copying the device
extent from the source to the target device. However just before we set
the block group to readonly mode some concurrent task might have already
allocated an extent from it or decided it could perform a nocow write
into one of its extents, which can make the device replace process to
miss copying an extent since it uses the extent tree's commit root to
search for extents and only once it finishes searching for all extents
belonging to the block group it does set the left cursor to the logical
end address of the block group - this is a problem if the respective
ordered extents finish while we are searching for extents using the
extent tree's commit root and no transaction commit happens while we
are iterating the tree, since it's the delayed references created by the
ordered extents (when they complete) that insert the extent items into
the extent tree (using the non-commit root of course).
Example:

          CPU 1                                            CPU 2

 btrfs_dev_replace_start()
   btrfs_scrub_dev()
     scrub_enumerate_chunks()
       --> finds device extent belonging
           to block group X

                               <transaction N starts>

                                                      starts buffered write
                                                      against some inode

                                                      writepages is run against
                                                      that inode forcing dellaloc
                                                      to run

                                                      btrfs_writepages()
                                                        extent_writepages()
                                                          extent_write_cache_pages()
                                                            __extent_writepage()
                                                              writepage_delalloc()
                                                                run_delalloc_range()
                                                                  cow_file_range()
                                                                    btrfs_reserve_extent()
                                                                      --> allocates an extent
                                                                          from block group X
                                                                          (which is not yet
                                                                           in RO mode)
                                                                    btrfs_add_ordered_extent()
                                                                      --> creates ordered extent Y
                                                        flush_epd_write_bio()
                                                          --> bio against the extent from
                                                              block group X is submitted

       btrfs_inc_block_group_ro(bg X)
         --> sets block group X to readonly

       scrub_chunk(bg X)
         scrub_stripe(device extent from srcdev)
           --> keeps searching for extent items
               belonging to the block group using
               the extent tree's commit root
           --> it never blocks due to
               fs_info->scrub_pause_req as no
               one tries to commit transaction N
           --> copies all extents found from the
               source device into the target device
           --> finishes search loop

                                                        bio completes

                                                        ordered extent Y completes
                                                        and creates delayed data
                                                        reference which will add an
                                                        extent item to the extent
                                                        tree when run (typically
                                                        at transaction commit time)

                                                          --> so the task doing the
                                                              scrub/device replace
                                                              at CPU 1 misses this
                                                              and does not copy this
                                                              extent into the new/target
                                                              device

       btrfs_dec_block_group_ro(bg X)
         --> turns block group X back to RW mode

       dev_replace->cursor_left is set to the
       logical end offset of block group X

So fix this by waiting for all cow and nocow writes after setting a block
group to readonly mode.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30 12:58:21 +01:00
Filipe Manana 57ba4cb85b Btrfs: fix race between device replace and block group removal
When it's finishing, the device replace code iterates all extent maps
representing block group and for each one that has a stripe that refers
to the source device, it replaces its device with the target device.
However when it replaces the source device with the target device it,
the target device still has an ID of 0ULL (BTRFS_DEV_REPLACE_DEVID),
only after its ID is changed to match the one from the source device.
This leads to races with the chunk removal code that can temporarly see
a device with an ID of 0ULL and then attempt to use that ID to remove
items from the device tree and fail, causing a transaction abort:

[ 9238.594364] BTRFS info (device sdf): dev_replace from /dev/sdf (devid 3) to /dev/sde finished
[ 9238.594377] ------------[ cut here ]------------
[ 9238.594402] WARNING: CPU: 14 PID: 21566 at fs/btrfs/volumes.c:2771 btrfs_remove_chunk+0x2e5/0x793 [btrfs]
[ 9238.594403] BTRFS: Transaction aborted (error 1)
[ 9238.594416] Modules linked in: btrfs crc32c_generic acpi_cpufreq xor tpm_tis tpm raid6_pq ppdev parport_pc processor psmouse parport i2c_piix4 evdev sg i2c_core se
rio_raw pcspkr button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix virtio_pci libata virtio_ring virtio e1000 scsi_mod fl
oppy [last unloaded: btrfs]
[ 9238.594418] CPU: 14 PID: 21566 Comm: btrfs-cleaner Not tainted 4.6.0-rc7-btrfs-next-29+ #1
[ 9238.594419] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[ 9238.594421]  0000000000000000 ffff88017f1dbc60 ffffffff8126b42c ffff88017f1dbcb0
[ 9238.594422]  0000000000000000 ffff88017f1dbca0 ffffffff81052b14 00000ad37f1dbd18
[ 9238.594423]  0000000000000001 ffff88018068a558 ffff88005c4b9c00 ffff880233f60db0
[ 9238.594424] Call Trace:
[ 9238.594428]  [<ffffffff8126b42c>] dump_stack+0x67/0x90
[ 9238.594430]  [<ffffffff81052b14>] __warn+0xc2/0xdd
[ 9238.594432]  [<ffffffff81052b7a>] warn_slowpath_fmt+0x4b/0x53
[ 9238.594434]  [<ffffffff8116c311>] ? kmem_cache_free+0x128/0x188
[ 9238.594450]  [<ffffffffa04d43f5>] btrfs_remove_chunk+0x2e5/0x793 [btrfs]
[ 9238.594452]  [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc
[ 9238.594464]  [<ffffffffa04a26fa>] btrfs_delete_unused_bgs+0x317/0x382 [btrfs]
[ 9238.594476]  [<ffffffffa04a961d>] cleaner_kthread+0x1ad/0x1c7 [btrfs]
[ 9238.594489]  [<ffffffffa04a9470>] ? btree_invalidatepage+0x8e/0x8e [btrfs]
[ 9238.594490]  [<ffffffff8106f403>] kthread+0xd4/0xdc
[ 9238.594494]  [<ffffffff8149e242>] ret_from_fork+0x22/0x40
[ 9238.594495]  [<ffffffff8106f32f>] ? kthread_stop+0x286/0x286
[ 9238.594496] ---[ end trace 183efbe50275f059 ]---

The sequence of steps leading to this is like the following:

              CPU 1                                           CPU 2

 btrfs_dev_replace_finishing()

   at this point
   dev_replace->tgtdev->devid ==
   BTRFS_DEV_REPLACE_DEVID (0ULL)

   ...

   btrfs_start_transaction()
   btrfs_commit_transaction()

                                                     btrfs_delete_unused_bgs()
                                                       btrfs_remove_chunk()

                                                         looks up for the extent map
                                                         corresponding to the chunk

                                                         lock_chunks() (chunk_mutex)
                                                         check_system_chunk()
                                                         unlock_chunks() (chunk_mutex)

   locks fs_info->chunk_mutex

   btrfs_dev_replace_update_device_in_mapping_tree()
     --> iterates fs_info->mapping_tree and
         replaces the device in every extent
         map's map->stripes[] with
         dev_replace->tgtdev, which still has
         an id of 0ULL (BTRFS_DEV_REPLACE_DEVID)

                                                         iterates over all stripes from
                                                         the extent map

                                                           --> calls btrfs_free_dev_extent()
                                                               passing it the target device
                                                               that still has an ID of 0ULL

                                                           --> btrfs_free_dev_extent() fails
                                                             --> aborts current transaction

   finishes setting up the target device,
   namely it sets tgtdev->devid to the value
   of srcdev->devid (which is necessarily > 0)

   frees the srcdev

   unlocks fs_info->chunk_mutex

So fix this by taking the device list mutex while processing the stripes
for the chunk's extent map. This is similar to the race between device
replace and block group creation that was fixed by commit 50460e3718
("Btrfs: fix race when finishing dev replace leading to transaction abort").

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30 12:58:19 +01:00
Filipe Manana ce7791ffee Btrfs: fix race between readahead and device replace/removal
The list of devices is protected by the device_list_mutex and the device
replace code, in its finishing phase correctly takes that mutex before
removing the source device from that list. However the readahead code was
iterating that list without acquiring the respective mutex leading to
crashes later on due to invalid memory accesses:

[125671.831036] general protection fault: 0000 [#1] PREEMPT SMP
[125671.832129] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis tpm ppdev evdev parport_pc psmouse sg parport
processor ser
[125671.834973] CPU: 10 PID: 19603 Comm: kworker/u32:19 Tainted: G        W       4.6.0-rc7-btrfs-next-29+ #1
[125671.834973] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[125671.834973] Workqueue: btrfs-readahead btrfs_readahead_helper [btrfs]
[125671.834973] task: ffff8801ac520540 ti: ffff8801ac918000 task.ti: ffff8801ac918000
[125671.834973] RIP: 0010:[<ffffffff81270479>]  [<ffffffff81270479>] __radix_tree_lookup+0x6a/0x105
[125671.834973] RSP: 0018:ffff8801ac91bc28  EFLAGS: 00010206
[125671.834973] RAX: 0000000000000000 RBX: 6b6b6b6b6b6b6b6a RCX: 0000000000000000
[125671.834973] RDX: 0000000000000000 RSI: 00000000000c1bff RDI: ffff88002ebd62a8
[125671.834973] RBP: ffff8801ac91bc70 R08: 0000000000000001 R09: 0000000000000000
[125671.834973] R10: ffff8801ac91bc70 R11: 0000000000000000 R12: ffff88002ebd62a8
[125671.834973] R13: 0000000000000000 R14: 0000000000000000 R15: 00000000000c1bff
[125671.834973] FS:  0000000000000000(0000) GS:ffff88023fd40000(0000) knlGS:0000000000000000
[125671.834973] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[125671.834973] CR2: 000000000073cae4 CR3: 00000000b7723000 CR4: 00000000000006e0
[125671.834973] Stack:
[125671.834973]  0000000000000000 ffff8801422d5600 ffff8802286bbc00 0000000000000000
[125671.834973]  0000000000000001 ffff8802286bbc00 00000000000c1bff 0000000000000000
[125671.834973]  ffff88002e639eb8 ffff8801ac91bc80 ffffffff81270541 ffff8801ac91bcb0
[125671.834973] Call Trace:
[125671.834973]  [<ffffffff81270541>] radix_tree_lookup+0xd/0xf
[125671.834973]  [<ffffffffa04ae6a6>] reada_peer_zones_set_lock+0x3e/0x60 [btrfs]
[125671.834973]  [<ffffffffa04ae8b9>] reada_pick_zone+0x29/0x103 [btrfs]
[125671.834973]  [<ffffffffa04af42f>] reada_start_machine_worker+0x129/0x2d3 [btrfs]
[125671.834973]  [<ffffffffa04880be>] btrfs_scrubparity_helper+0x185/0x3aa [btrfs]
[125671.834973]  [<ffffffffa0488341>] btrfs_readahead_helper+0xe/0x10 [btrfs]
[125671.834973]  [<ffffffff81069691>] process_one_work+0x271/0x4e9
[125671.834973]  [<ffffffff81069dda>] worker_thread+0x1eb/0x2c9
[125671.834973]  [<ffffffff81069bef>] ? rescuer_thread+0x2b3/0x2b3
[125671.834973]  [<ffffffff8106f403>] kthread+0xd4/0xdc
[125671.834973]  [<ffffffff8149e242>] ret_from_fork+0x22/0x40
[125671.834973]  [<ffffffff8106f32f>] ? kthread_stop+0x286/0x286

So fix this by taking the device_list_mutex in the readahead code. We
can't use here the lighter approach of using a rcu_read_lock() and
rcu_read_unlock() pair together with a list_for_each_entry_rcu() call
because we end up doing calls to sleeping functions (kzalloc()) in the
respective code path.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30 12:58:18 +01:00
Aaron Lu 9f9cd7ee2c ACPI / Thermal / video: fix max_level incorrect value
commit 059500940d (ACPI/video: export acpi_video_get_levels)
mistakenly dropped the correct value of max_level and that caused the
set_level function following failed and the acpi_video backlight interface
didn't get created. Fix this by passing back the correct max_level value.

While at it, also fix the param used in acpi_video_device_lcd_query_levels
where acpi_handle is expected but acpi_video_device is passed.

Fixes: 059500940d (ACPI/video: export acpi_video_get_levels)
Reported-and-tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-30 13:53:09 +02:00
Geert Uytterhoeven 9feeed94d0 MAINTAINERS: Add file patterns for pinctrl device tree bindings
Submitters of device tree binding documentation may forget to CC
the subsystem maintainer if this is missing.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 09:42:37 +02:00
Linus Walleij 6b1a7c9ecd pinctrl: nomadik: fix inversion of gpio direction
The input/output directions were inversed on the GPIO direction
read function. Loose a ! and it is correct.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 09:42:37 +02:00
Linus Walleij 9c10280d85 gpio: flush direction status in gpiochip_lock_as_irq()
As irqchip and gpiochip functions are orthogonal, the IRQ
set-up or something else can have changed the direction of
the GPIO line from what the GPIO descriptor knows when we
get into gpiochip_lock_as_irq(). Make sure to re-read the
direction setting if we have the .get_direction() callback
enabled for the chip.

Else we get problems like this:

iio iio:device2: interrupts on the rising edge
gpio gpiochip2: (8012e080.gpio): gpiochip_lock_as_irq:
  tried to flag a GPIO set as output for IRQ
gpio gpiochip2: (8012e080.gpio): unable to lock HW IRQ 0 for IRQ
genirq: Failed to request resources for l3g4200d-trigger
  (irq 111) on irqchip nmk1-32-63
iio iio:device2: failed to request trigger IRQ.
st-gyro-i2c: probe of 2-0068 failed with error -22

Fixes: 72d3200061 ("gpio: set up initial state from .get_direction()")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 09:42:03 +02:00
Sylvain Lemieux 320a6480ef gpio: lpc32xx: disable broken to_irq support
The "to_irq" functionality is broken inside this driver since commit
76ba59f836 ("genirq: Add irq_domain-aware core IRQ handler").

The addition of the new lpc32xx irqchip driver in 4.7, fixed the
lpc32xx platform interrupt issue.

When switching to the new lpc32xx irqchip driver, a warning appear
in the lpc32xx gpio driver: warning: "NR_IRQS" redefined.

To remove this warning (temporary solution), this patch
disables the broken "to_irq" mapping functionality support.

Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 09:42:03 +02:00
Liu Ying 151787ba05 drm/imx: plane: Don't set plane->crtc in ipu_plane_update()
Since the drm core sets plane->crtc correctly, we don't need to do that.

Signed-off-by: Liu Ying <gnuiyl@gmail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Liu Ying 8b3ce87377 drm/imx: ipuv3-plane: Constify ipu_plane_funcs
Signed-off-by: Liu Ying <gnuiyl@gmail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Lothar Waßmann c82b4d73e2 drm/imx: imx-ldb: honor 'native-mode' property when selecting video mode from DT
This patch allows to select a specific video mode from a list of modes
defined in DT by setting the 'native-mode' property appropriately.

This change does not affect the behaviour of existing platforms, since
they either:
   - have just one display-timings subnode
   - have the native-mode property pointing to the first entry
   - let the bootloader select the appropriate timing

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Lothar Waßmann 97a6075d7c drm/imx: parallel-display: remove dead code
The 'mode_valid' flag is never set in this driver. Remove it and the
code that depends on it.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Philipp Zabel 4ed094fd73 drm/imx: use bus_flags for pixel clock polarity
This patch allows panels to set pixel clock and data enable pin polarity
other than the default of driving data at the falling pixel clock edge
and active high display enable.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Philipp Zabel 7932131f63 drm/imx: ipuv3-plane: enable UYVY and VYUY formats
Advertise the DRM_FORMAT_UYVY and DRM_FORMAT_VYUY formats to userspace.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Philipp Zabel 3a1c117f8b drm/imx: parallel-display: use of_graph_get_endpoint_by_regs helper
Instead of using of_graph_get_port_by_id() to get the port and then
of_get_child_by_name() to get the first endpoint, get to the endpoint
in a single step.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Philipp Zabel 620011e047 drm/imx: imx-ldb: use of_graph_get_endpoint_by_regs helper
Instead of using of_graph_get_port_by_id() to get the port and then
of_get_child_by_name() to get the first endpoint, get to the endpoint
in a single step.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Akshay Bhat ee89686631 dt-bindings: imx: ldb: Add ddc-i2c-bus property
Document the ddc-i2c-bus property used by imx-ldb driver to read EDID
information via I2C interface.

Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00
Steve Longerbeam a6d206e28a drm/imx: imx-ldb: Add DDC support
Add support for reading EDID over Display Data Channel. If no DDC
adapter is available, falls back to hardcoded EDID or display-timings
node as before.

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2016-05-30 09:14:00 +02:00