commit 447ae31667 upstream
The next patch in this series will have to make the definition of
irq_cpustat_t available to entering_irq().
Inclusion of asm/hardirq.h into asm/apic.h would cause circular header
dependencies like
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/topology.h
linux/smp.h
asm/smp.h
or
linux/gfp.h
linux/mmzone.h
asm/mmzone.h
asm/mmzone_64.h
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/irqdesc.h
linux/kobject.h
linux/sysfs.h
linux/kernfs.h
linux/idr.h
linux/gfp.h
and others.
This causes compilation errors because of the header guards becoming
effective in the second inclusion: symbols/macros that had been defined
before wouldn't be available to intermediate headers in the #include chain
anymore.
A possible workaround would be to move the definition of irq_cpustat_t
into its own header and include that from both, asm/hardirq.h and
asm/apic.h.
However, this wouldn't solve the real problem, namely asm/harirq.h
unnecessarily pulling in all the linux/irq.h cruft: nothing in
asm/hardirq.h itself requires it. Also, note that there are some other
archs, like e.g. arm64, which don't have that #include in their
asm/hardirq.h.
Remove the linux/irq.h #include from x86' asm/hardirq.h.
Fix resulting compilation errors by adding appropriate #includes to *.c
files as needed.
Note that some of these *.c files could be cleaned up a bit wrt. to their
set of #includes, but that should better be done from separate patches, if
at all.
Signed-off-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5e9cfeba6a ]
drm_atomic_helper_shutdown() needs to release the reference held by
plane->fb. Since commit 49d70aeaec ("drm/atomic-helper: Fix leak in
disable_all") we're doing that by calling drm_atomic_clean_old_fb() in
drm_atomic_helper_disable_all(). This also leaves plane->fb == NULL
afterwards. However, since drm_atomic_helper_disable_all() is also
used by the i915 gpu reset code
drm_atomic_helper_commit_duplicated_state() then has to undo the
damage and put the correct plane->fb pointers back in (and also
adjust the ref counts to match again as well).
That approach doesn't work so well for load detection as nothing
sets up the plane->old_fb pointers for us. This causes us to
leak an extra reference for each plane->fb when
drm_atomic_helper_commit_duplicated_state() calls
drm_atomic_clean_old_fb() after load detection.
To fix this let's call drm_atomic_clean_old_fb() only for
drm_atomic_helper_shutdown() as that's the only time we need to
actually drop the plane->fb references. In all the other cases
(load detection, gpu reset) we want to leave plane->fb alone.
v2: Don't inflict the clean_old_fbs bool to drivers (Daniel)
v3: Squash in the revert and rewrite the commit msg (Daniel)
Cc: martin.peres@free.fr
Cc: chris@chris-wilson.co.uk
Cc: Dave Airlie <airlied@gmail.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180322152313.6561-3-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> #pre-squash
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7a47f20eb1 ]
The method struct drm_connector_helper_funcs::mode_valid is defined
as returning an 'enum drm_mode_status' but the driver implementation
for this method uses an 'int' for it.
Fix this by using 'enum drm_mode_status' in the driver too.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4f2fc25c0f ]
Newer HW doesn't appear to send this event, which will cause long delays
in runlist updates if they don't complete immediately.
RM doesn't use these events anywhere, and an NVGPU commit message notes
that polling is the preferred method even on HW that supports the event.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit eb493fbc15 upstream.
Currently nouveau doesn't actually expose the state debugfs file that's
usually provided for any modesetting driver that supports atomic, even
if nouveau is loaded with atomic=1. This is due to the fact that the
standard debugfs files that DRM creates for atomic drivers is called
when drm_get_pci_dev() is called from nouveau_drm.c. This happens well
before we've initialized the display core, which is currently
responsible for setting the DRIVER_ATOMIC cap.
So, move the atomic option into nouveau_drm.c and just add the
DRIVER_ATOMIC cap whenever it's enabled on the kernel commandline. This
shouldn't cause any actual issues, as the atomic ioctl will still fail
as expected even if the display core doesn't disable it until later in
the init sequence. This also provides the added benefit of being able to
use the state debugfs file to check the current display state even if
clients aren't allowed to modify it through anything other than the
legacy ioctls.
Additionally, disable the DRIVER_ATOMIC cap in nv04's display core, as
this was already disabled there previously.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 37afe55b4a upstream.
When MST and atomic were introduced to nouveau, another structure that
could contain a drm_connector embedded within it was introduced; struct
nv50_mstc. This meant that we no longer would be able to simply loop
through our connector list and assume that nouveau_connector() would
return a proper pointer for each connector, since the assertion that
all connectors coming from nouveau have a full nouveau_connector struct
became invalid.
Unfortunately, none of the actual code that looped through connectors
ever got updated, which means that we've been causing invalid memory
accesses for quite a while now.
An example that was caught by KASAN:
[ 201.038698] ==================================================================
[ 201.038792] BUG: KASAN: slab-out-of-bounds in nvif_notify_get+0x190/0x1a0 [nouveau]
[ 201.038797] Read of size 4 at addr ffff88076738c650 by task kworker/0:3/718
[ 201.038800]
[ 201.038822] CPU: 0 PID: 718 Comm: kworker/0:3 Tainted: G O 4.18.0-rc4Lyude-Test+ #1
[ 201.038825] Hardware name: LENOVO 20EQS64N0B/20EQS64N0B, BIOS N1EET78W (1.51 ) 05/18/2018
[ 201.038882] Workqueue: events nouveau_display_hpd_work [nouveau]
[ 201.038887] Call Trace:
[ 201.038894] dump_stack+0xa4/0xfd
[ 201.038900] print_address_description+0x71/0x239
[ 201.038929] ? nvif_notify_get+0x190/0x1a0 [nouveau]
[ 201.038935] kasan_report.cold.6+0x242/0x2fe
[ 201.038942] __asan_report_load4_noabort+0x19/0x20
[ 201.038970] nvif_notify_get+0x190/0x1a0 [nouveau]
[ 201.038998] ? nvif_notify_put+0x1f0/0x1f0 [nouveau]
[ 201.039003] ? kmsg_dump_rewind_nolock+0xe4/0xe4
[ 201.039049] nouveau_display_init.cold.12+0x34/0x39 [nouveau]
[ 201.039089] ? nouveau_user_framebuffer_create+0x120/0x120 [nouveau]
[ 201.039133] nouveau_display_resume+0x5c0/0x810 [nouveau]
[ 201.039173] ? nvkm_client_ioctl+0x20/0x20 [nouveau]
[ 201.039215] nouveau_do_resume+0x19f/0x570 [nouveau]
[ 201.039256] nouveau_pmops_runtime_resume+0xd8/0x2a0 [nouveau]
[ 201.039264] pci_pm_runtime_resume+0x130/0x250
[ 201.039269] ? pci_restore_standard_config+0x70/0x70
[ 201.039275] __rpm_callback+0x1f2/0x5d0
[ 201.039279] ? rpm_resume+0x560/0x18a0
[ 201.039283] ? pci_restore_standard_config+0x70/0x70
[ 201.039287] ? pci_restore_standard_config+0x70/0x70
[ 201.039291] ? pci_restore_standard_config+0x70/0x70
[ 201.039296] rpm_callback+0x175/0x210
[ 201.039300] ? pci_restore_standard_config+0x70/0x70
[ 201.039305] rpm_resume+0xcc3/0x18a0
[ 201.039312] ? rpm_callback+0x210/0x210
[ 201.039317] ? __pm_runtime_resume+0x9e/0x100
[ 201.039322] ? kasan_check_write+0x14/0x20
[ 201.039326] ? do_raw_spin_lock+0xc2/0x1c0
[ 201.039333] __pm_runtime_resume+0xac/0x100
[ 201.039374] nouveau_display_hpd_work+0x67/0x1f0 [nouveau]
[ 201.039380] process_one_work+0x7a0/0x14d0
[ 201.039388] ? cancel_delayed_work_sync+0x20/0x20
[ 201.039392] ? lock_acquire+0x113/0x310
[ 201.039398] ? kasan_check_write+0x14/0x20
[ 201.039402] ? do_raw_spin_lock+0xc2/0x1c0
[ 201.039409] worker_thread+0x86/0xb50
[ 201.039418] kthread+0x2e9/0x3a0
[ 201.039422] ? process_one_work+0x14d0/0x14d0
[ 201.039426] ? kthread_create_worker_on_cpu+0xc0/0xc0
[ 201.039431] ret_from_fork+0x3a/0x50
[ 201.039441]
[ 201.039444] Allocated by task 79:
[ 201.039449] save_stack+0x43/0xd0
[ 201.039452] kasan_kmalloc+0xc4/0xe0
[ 201.039456] kmem_cache_alloc_trace+0x10a/0x260
[ 201.039494] nv50_mstm_add_connector+0x9a/0x340 [nouveau]
[ 201.039504] drm_dp_add_port+0xff5/0x1fc0 [drm_kms_helper]
[ 201.039511] drm_dp_send_link_address+0x4a7/0x740 [drm_kms_helper]
[ 201.039518] drm_dp_check_and_send_link_address+0x1a7/0x210 [drm_kms_helper]
[ 201.039525] drm_dp_mst_link_probe_work+0x71/0xb0 [drm_kms_helper]
[ 201.039529] process_one_work+0x7a0/0x14d0
[ 201.039533] worker_thread+0x86/0xb50
[ 201.039537] kthread+0x2e9/0x3a0
[ 201.039541] ret_from_fork+0x3a/0x50
[ 201.039543]
[ 201.039546] Freed by task 0:
[ 201.039549] (stack is not available)
[ 201.039551]
[ 201.039555] The buggy address belongs to the object at ffff88076738c1a8
which belongs to the cache kmalloc-2048 of size 2048
[ 201.039559] The buggy address is located 1192 bytes inside of
2048-byte region [ffff88076738c1a8, ffff88076738c9a8)
[ 201.039563] The buggy address belongs to the page:
[ 201.039567] page:ffffea001d9ce200 count:1 mapcount:0 mapping:ffff88084000d0c0 index:0x0 compound_mapcount: 0
[ 201.039573] flags: 0x8000000000008100(slab|head)
[ 201.039578] raw: 8000000000008100 ffffea001da3be08 ffffea001da25a08 ffff88084000d0c0
[ 201.039582] raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000
[ 201.039585] page dumped because: kasan: bad access detected
[ 201.039588]
[ 201.039591] Memory state around the buggy address:
[ 201.039594] ffff88076738c500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 201.039598] ffff88076738c580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 201.039601] >ffff88076738c600: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
[ 201.039604] ^
[ 201.039607] ffff88076738c680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 201.039611] ffff88076738c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 201.039613] ==================================================================
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Cc: Karol Herbst <karolherbst@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 22b76bbe08 upstream.
Every codepath in nouveau that loops through the connector list
currently does so using the old method, which is prone to race
conditions from MST connectors being created and destroyed. This has
been causing a multitude of problems, including memory corruption from
trying to access connectors that have already been freed!
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Cc: Karol Herbst <karolherbst@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 99ec9e7751 upstream.
The displaylink hardware has such a peculiarity that it doesn't render a
command until next command is received. This produces occasional
corruption, such as when setting 22x11 font on the console, only the first
line of the cursor will be blinking if the cursor is located at some
specific columns.
When we end up with a repeating pixel, the driver has a bug that it leaves
one uninitialized byte after the command (and this byte is enough to flush
the command and render it - thus it fixes the screen corruption), however
whe we end up with a non-repeating pixel, there is no byte appended and
this results in temporary screen corruption.
This patch fixes the screen corruption by always appending a byte 0xAF at
the end of URB. It also removes the uninitialized byte.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2b6207291b ]
There is a comment here which says that DIV_ROUND_UP() and that's where
the problem comes from. Say you pick:
args->bpp = UINT_MAX - 7;
args->width = 4;
args->height = 1;
The integer overflow in DIV_ROUND_UP() means "cpp" is UINT_MAX / 8 and
because of how we picked args->width that means cpp < UINT_MAX / 4.
I've fixed it by preventing the integer overflow in DIV_ROUND_UP(). I
removed the check for !cpp because it's not possible after this change.
I also changed all the 0xffffffffU references to U32_MAX.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180516140026.GA19340@mwanda
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1cf6cc74bb ]
Currently if a user requests clock counters for a node without a GPU
resource we will always return EINVAL.
Instead if no GPU resource is attached, fill the gpu_clock_counter
argument with zeroes so that we may proceed and return valid CPU
counters.
Signed-off-by: Andres Rodriguez <andres.rodriguez@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a4af89286f ]
The function dsi_get_cmd_fmt returns enum dsi_cmd_dst_format,
use the correct enum value also for MIPI_DSI_FMT_RGB666/_PACKED.
This has been discovered using clang:
drivers/gpu/drm/msm/dsi/dsi_host.c:743:35: warning: implicit conversion
from enumeration type 'enum dsi_vid_dst_format' to different
enumeration type 'enum dsi_cmd_dst_format' [-Wenum-conversion]
case MIPI_DSI_FMT_RGB666: return VID_DST_FORMAT_RGB666;
~~~~~~ ^~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3976626ea3 ]
Commit 62e3a3e342 changed get_pages() to initialise
msm_gem_object::pages before trying to initialise msm_gem_object::sgt,
so that put_pages() would properly clean up pages in the failure
case.
However, this means that put_pages() now needs to check that
msm_gem_object::sgt is not null before trying to clean it up, and
this check was only applied to part of the cleanup code. Move
it all into the conditional block. (Strictly speaking we don't
need to make the kfree() conditional, but since we can't avoid
checking for null ourselves we may as well do so.)
Fixes: 62e3a3e342 ("drm/msm: fix leak in failed get_pages")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Reviewed-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 76ef6b28ea upstream.
Since we have the ttm and gem vma managers using a subset
of the file address space for objects, and these start at
0x100000000 they will overflow the new mmap checks.
I've checked all the mmap routines I could see for any
bad behaviour but overall most people use GEM/TTM VMA
managers even the legacy drivers have a hashtable.
Reported-and-Tested-by: Arthur Marsh (amarsh04 on #radeon)
Fixes: be83bbf806 (mmap: introduce sane default mmap limits)
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 42b5122e82 upstream.
In several locations the driver uses AMD_CG_STATE_UNGATE (type enum
amd_clockgating_state) instead of AMD_PG_STATE_UNGATE (type enum
amd_powergating_stat) and vice versa. Both constants have the same
value, so this doesn't cause any problems, but we still want to pass
the correct type.
Fixing the mismatch resolves multiple warnings like this when building
with clang:
drivers/gpu/drm/amd/amdgpu/../powerplay/hwmgr/cz_clockpowergating.c:169:7:
error: implicit conversion from enumeration type 'enum
amd_powergating_state' to different enumeration type 'enum
amd_clockgating_state' [-Werror,-Wenum-conversion]
AMD_PG_STATE_UNGATE);
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 91ba9f28a3 upstream.
SOU primary plane prepare_fb hook depends upon dmabuf_size to pin up BO
(and not call a new vmw_dmabuf_init) when a new fb size is same as
current fb. This was changed in a recent commit which is causing
page_flip to fail on VM with low display memory and multi-mon failure
when cycle monitors from secondary display.
Cc: <stable@vger.kernel.org> # 4.14, 4.16
Fixes: 20fb5a635a ("drm/vmwgfx: Unpin the screen object backup buffer when not used")
Signed-off-by: Deepak Rawat <drawat@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit dbf797655a ]
issue:
sometime GFX/MM ib test hit timeout under SRIOV env, root cause
is that engine doesn't come back soon enough so the current
IB test considered as timed out.
fix:
for SRIOV GFX IB test wait time need to be expanded a lot during
SRIOV runtimei mode since it couldn't really begin before GFX engine
come back.
for SRIOV MM IB test it always need more time since MM scheduling
is not go together with GFX engine, it is controled by h/w MM
scheduler so no matter runtime or exclusive mode MM IB test
always need more time.
v2:
use ring type instead of idx to judge
Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9f0178fb67 ]
otherwise there will be DMAR reading error comes out from CP since
GFX is still alive and CPC's WPTR_POLL is still enabled, which would
lead to DMAR read error.
fix:
we can hault CPG after hw_fini, but cannot halt CPC becaues KIQ
stil need to be alive to let RLCV invoke, but its WPTR_POLL could
be disabled.
Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 215003b4ae ]
There's no reason to delay initialization of most of the driver (such as
mapping memory I/O, getting clocks or enabling runtime PM) to the
component master bind handler.
This additionally fixes a real PM issue caused enabling runtime PM in
the bind handler.
The bind handler performs the following sequence of PM operations:
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
... (access the hardware to read the device revision) ...
pm_runtime_put_sync(dev);
If a failure occurs at this point, the error path calls
pm_runtime_disable() to balance the pm_runtime_enable() call.
To understand the problem, it should be noted that the bind handler is
called when one of the component registers itself, which happens in the
component's probe handler. Furthermore, as the components are children
of the DSS, the device core calls pm_runtime_get_sync() on the DSS
platform device before calling the component's probe handler. This
increases the DSS power usage count but doesn't runtime resume the
device, as runtime PM is disabled at that point.
The bind handler is thus called with runtime PM disabled, with the
device runtime suspended, but with the power usage count larger than 0.
The pm_runtime_get_sync() call will thus further increase the power
usage count and runtime resume the device. The pm_runtime_put_sync()
handler will decrease the power usage count to a non-zero value and will
thus not suspend the device. Finally, the pm_runtime_disable() call will
disable runtime PM, preventing the pm_runtime_put() call in the device
core from runtime suspending the device. The DSS device is thus left
powered on.
To fix this, move the initialization code from the bind handler to the
probe handler.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2e7a66a8b5 ]
The following happens when connection a DVI output driven
from the SiI9022 using a DVI-to-VGA adapter plug:
i2c i2c-0: sendbytes: NAK bailout.
i2c i2c-0: sendbytes: NAK bailout.
Then no picture. Apparently the I2C engine inside the SiI9022
is not smart enough to try to fall back to DDC I2C. Or the
vendor have not integrated the electronics properly. I don't
know which one it is.
After this, the I2C bus seems stalled and the first attempt to
read the status register fails, and the code returns with
negative return value, and the display fails to initialized.
Instead, retry status readout five times and continue even
if this fails.
Tested on the ARM Versatile Express with a DVI-to-VGA
connector, it now gives picture.
Introduce a helper struct device *dev variable to make
the code more readable.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180305101702.13441-1-linus.walleij@linaro.org
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nicolai Stange