They aren't going anywhere, and probing on DDC can cause the panel to
blank briefly, so read them up front and cache them for later queries.
v2: fix potential NULL derefs in intel_dp_get_edid_modes and
intel_dp_get_edid (Jani)
copy full EDID length, including extension blocks (Takashi)
free EDID on teardown (Takashi)
v3: malloc a new EDID buffer that's big enough for the memcpy (Chris)
v4: change handling of NULL EDIDs, just preserve the NULL behavior
across detects and mode list fetches rather than trying to re-fetch
the EDID (Chris)
v5: be glad that Chris is around to remind me to hit C-x C-s before
committing.
References: https://bugs.freedesktop.org/show_bug.cgi?id=46856
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This reverts commit 092945e11c.
This commit prevents a DP screen from properly training the link.
Oddly enough it works, once the machine has been warm-booted with an
older kernel.
According to DP docs this _should_ have been the right precharge time.
Also, the commit that originally introduces this was just general snb
DP enabling and didn't mention any specific reason for this special
value. Whatever, trust the reporter that this makes things worse and
let's just revert it.
v2: Less spelling fail.
Cc: Adam Jackson <ajax@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Reported-by: "Wouter M. Koolen" <W.M.Koolen-Wijkstra@cwi.nl>
Buglink: https://lkml.org/lkml/2012/6/14/301
Cc: stable@vger.kernel.org (only for 3.4)
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The new oui probe has been missing these.
This issue has been introduce in
commit 0d19832853
Author: Adam Jackson <ajax@redhat.com>
Date: Mon May 14 16:05:47 2012 -0400
drm/i915/dp: Probe branch/sink OUIs
v2: Do the eDP vdd dance of simply not probing the OUI on eDP panels
as suggested by Chris Wilson.
v3: Fix up the error path fail - I suck.
Cc: Adam Jackson <ajax@redhat.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50808
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Bugreport: http://permalink.gmane.org/gmane.comp.video.dri.devel/69695
Tested-by: Yang Guang <guang.a.yang@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: tune down the noise of the RP irq limit fail
drm/i915: Remove the error message for unbinding pinned buffers
drm/i915: Limit page allocations to lowmem (dma32) for i965
drm/i915: always use RPNSWREQ for turbo change requests
drm/i915: reject doubleclocked cea modes on dp
drm/i915: Adding TV Out Missing modes.
drm/i915: wait for a vblank to pass after tv detect
drm/i915: no lvds quirk for HP t5740e Thin Client
drm/i915: enable vdd when switching off the eDP panel
drm/i915: Fix PCH PLL assertions to not assume CRTC:PLL relationship
drm/i915: Always update RPS interrupts thresholds along with frequency
drm/i915: properly handle interlaced bit for sdvo dtd conversion
drm/i915: fix module unload since error_state rework
drm/i915: be more careful when returning -ENXIO in gmbus transfer
These are ultra-low-res modes used to upscale SDTV content and we
don't know how to support these on dp on intel hw:
- It's unclear whether we can send avi infoframes over dp ports.
- And the pixel repeat setting that work for hdmi/sdvo explicitly
don't work for dp.
So don't bother and just reject these modes. These modes have been
introduced in
commit 54ac76f851
Author: Christian Schmidt <schmidt@digadd.de>
Date: Mon Dec 19 14:53:16 2011 +0000
drm/edid: support CEA video modes.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45729
Tested-by: Yuang Guang <guang.a.yang@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We have one bug report from a validation team that we get the eDP
panel sequencing still somewhat wrong: We need to enable VDD while
switching off the panel and backlight. Unfortunately that reporter
seems to have fallen off the earth :(
For another reporter this actually fixes a black panel issue because
without this the backlight/panel gets confused and doesn't light up
again.
v2: I've forgotten to remove the vdd_off call in panel_off which is
now bogus. This essentially reverts
commit 17038de5f1
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon Apr 16 22:43:42 2012 +0100
drm/i915/dp: Flush any outstanding work to turn the VDD off
v3: the current panel_off code forces off the vdd power, too. Which is
bogus and resulted in some funny warnings later on when we've tried to
do aux channel communications with just the vdd forced on. Fix this,
too.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=46312
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43163
Tested-by: Vincent Frentzel <zcecc22@gmail.com>
Cc: stable@kernel.org
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
PCH PLLs aren't required for outputs on the CPU, so we shouldn't just
treat them as part of the pipe.
So split the code out and manage PCH PLLs separately, allocating them
when needed or trying to re-use existing PCH PLL setups when the timings
match.
v2: add num_pch_pll field to dev_priv (Daniel)
don't NULL the pch_pll pointer in disable or DPMS will fail (Jesse)
put register offsets in pll struct (Chris)
v3: Decouple enable/disable of PLLs from get/put.
v4: Track temporary PLL disabling during modeset
v5: Tidy PLL initialisation by only checking for num_pch_pll == 0 (Eugeni)
v6: Avoid mishandling allocation failure by embedding the small array of
PLLs into the device struct
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44309
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> (up to v2)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v3+)
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Tested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pretty useful to debug our DP bandwidth woes.
v2: Also print out the required and available link bandwidth,
suggested by Chris Wilson.
v3: Also print out the input parameters so that diagnosing failures to
find a valid dp link configuration is possible.
v4: s/Display port/DP/ to shorten the output.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v3.4-rc3' into drm-intel-next-queued
Backmerge Linux 3.4-rc3 into drm-intel-next to resolve a few things
that conflict/depend upon patches in -rc3:
- Second part of the Sandybridge workaround series - it changes some
of the same registers.
- Preparation for Chris Wilson's fencing cleanup - we need the fix
from -rc3 merged before we can move around all that code.
- Resolve the gmbus conflict - gmbus has been disabled in 3.4 again,
but should be enabled on all generations in 3.5.
Conflicts:
drivers/gpu/drm/i915/intel_i2c.c
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As we may kick off a delayed workqueue task to switch of the VDD lines, we
need to complete that task prior to turning off the panel (which itself
depends upon VDD being off).
v2: Don't cancel the outstanding work as this may trigger a deadlock
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If these regs don't have valid values, the panel won't come up, and may
even cause a system hang. So do a basic sanity check when an eDP panel
is detected.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44305
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We've only computed whether we need to fall back to 6bpc due to dp
link bandwidth constrains in mode_valid, but not mode_fixup. Under
various circumstances X likes to create new modes which then lack
proper 6bpc flags (if required), resulting in mode_fixup failures and
ultimately black screens.
Chris Wilson pointed out that we still get things wrong for bpp > 24,
but that should be fixed in another patch (and it'll be easier because
this patch consolidates the logic).
The likely culprit for this regression is
commit 3d794f87238f74d80e78a7611c7fbde8a54c85c2
Author: Keith Packard <keithp@keithp.com>
Date: Wed Jan 25 08:16:25 2012 -0800
drm/i915: Force explicit bpp selection for intel_dp_link_required
v2: Fix indentation and tune down the too bold claim that this should
fix the world. Both noticed by Chris Wilson.
v3: Try to really git add things.
Reported-and-tested-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=48170
Cc: stable@kernel.org
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
While fixing up a merge conflict with drm-next I've noticed that we
use the same audio drm connector property also for dp and sdvo
outputs.
So put the new enum to some good use and convert these paths, too. The
HDMI_AUDIO_ prefix is a bit a misnomer. But at least for sdvo it makes
sense (and you can also connect a hdmi monitor with a dp->hdmi cable),
so I've decided to stick with it.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Back-merge from drm-fixes into drm-intel-next to sort out two things:
- interlaced support: -fixes contains a bugfix to correctly clear
interlaced configuration bits in case the bios sets up an interlaced
mode and we want to set up the progressive mode (current kernels
don't support interlaced). The actual feature work to support
interlaced depends upon (and conflicts with) this bugfix.
- forcewake voodoo to workaround missed IRQ issues: -fixes only enabled
this for ivybridge, but some recent bug reports indicate that we
need this on Sandybridge, too. But in a slightly different flavour
and with other fixes and reworks on top. Additionally there are some
forcewake cleanup patches heading to -next that would conflict with
currrent -fixes.
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It is never correct to use intel_crtc->bpp in intel_dp_link_required,
so instead pass an explicit bpp in to this function. This patch
only supports 18bpp and 24bpp modes, which means that 10bpc modes will
be computed incorrectly. Fixing that will require more extensive
changes, and so must be addressed separately from this bugfix.
intel_dp_link_required is called from intel_dp_mode_valid and
intel_dp_mode_fixup.
* intel_dp_mode_valid is called to list supported modes; in this case,
the current crtc values cannot be relevant as the modes in question
may never be selected. Thus, using intel_crtc->bpp is never right.
* intel_dp_mode_fixup is called during mode setting, but it is run
well before ironlake_crtc_mode_set is called to set intel_crtc->bpp,
so using intel_crtc-bpp in this path can only ever get a stale
value.
Cc: Lubos Kolouch <lubos.kolouch@gmail.com>
Cc: Adam Jackson <ajax@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42263
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44881
Tested-by: Dave Airlie <airlied@redhat.com>
Tested-by: camalot@picnicpark.org (Dell Latitude 6510)
Tested-by: Roland Dreier <roland@digitalvampire.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
This is paranoid, but I am entirely willing to believe the hardware
could come up with a condition where I get a status with both the 'done'
and 'receive error' bits set.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The default in the Sandybridge docs is 5, as on Ironlake, and I have no
reason to believe 3 would work any better.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Matches the advice in the Sandybridge documentation.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On DP monitor hot remove, clear DP_AUDIO_OUTPUT_ENABLE accordingly,
so that the audio driver will receive hot plug events and take action
to refresh its device state and ELD contents.
Note that the DP_AUDIO_OUTPUT_ENABLE bit may be enabled or disabled
only when the link training is complete and set to "Normal".
Tested OK for both hot plug/remove and DPMS on/off.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Some active adaptors (VGA usually) only have two lanes at 2.7GHz.
That's a maximum pixel clock of 144MHz at 8bpc, but 192MHz at 6bpc.
Fixes Asus UX31 panel being black at startup due to no valid modes since
dc22ee6fc1.
v2: Rebased to current code, resulting in the fix applying to EDP panels as
well. Also changed from spatio-temporal to just spatial dithering on
pre-ironlake, to be conssitent (and less visual flicker)
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Tested-by: Eric Anholt <eric@anholt.net>
Tested-by: Dirk Hohndel <hohndel@infradead.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
The Ivybridge eDP control register looks like a cross between a
Cougarpoint PCH DP control register and a Sandybridge eDP control
register.
Where things trivially match, share the code. Where there are any
tricky bits, just split things out into two obviously separate code paths.
Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Fang Xun <xunx.fang@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41991
* 'drm-intel-fixes' of git://people.freedesktop.org/~keithp/linux: (25 commits)
drm/i915: Fix inconsistent backlight level during disabled
drm, i915: Fix memory leak in i915_gem_busy_ioctl().
drm/i915: Use DPCD value for max DP lanes.
drm/i915: Initiate DP link training only on the lanes we'll be using
drm/i915: Remove trailing white space
drm/i915: Try harder during dp pattern 1 link training
drm/i915: Make DP prepare/commit consistent with DP dpms
drm/i915: Let panel power sequencing hardware do its job
drm/i915: Treat PCH eDP like DP in most places
drm/i915: Remove link_status field from intel_dp structure
drm/i915: Move common PCH_PP_CONTROL setup to ironlake_get_pp_control
drm/i915: Module parameters using '-1' as default must be signed type
drm/i915: Turn on another required clock gating bit on gen6.
drm/i915: Turn on a required 3D clock gating bit on Sandybridge.
drm/i915: enable cacheable objects on Ivybridge
drm/i915: add constants to size fence arrays and fields
drm/i915: Ivybridge still has fences!
drm/i915: forcewake warning fixes in debugfs
drm/i915: Fix object refcount leak on mmappable size limit error path.
drm/i915: Use mode_config.mutex in ironlake_panel_vdd_work
...
The BIOS VBT value for an eDP panel has been shown to be incorrect on
one machine, and we haven't found any machines where the DPCD value
was wrong, so we'll use the DPCD value everywhere.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Limit the link training setting command to the lanes needed for the
current mode. It seems vaguely possible that a monitor will try to
train the other lanes and fail in some way, so this seems like the
safer plan.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Instead of going through the sequence just once, run through the whole
set up to 5 times to see if something can work. This isn't part of the
DP spec, but the BIOS seems to do it, and given that link training
failure is so bad, it seems reasonable to follow suit.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Make sure the sequence of operations in all three functions makes
sense:
1) The backlight must be off unless the screen is running
2) The link must be running to turn the eDP panel on/off
3) The CPU eDP PLL must be running until everything is off
Signed-off-by: Keith Packard <keithp@keithp.com>
The panel power sequencing hardware tracks the stages of panel power
sequencing and signals when the panel is completely on or off. Instead
of blindly assuming the panel timings will work, poll the panel power
status register until it shows the correct values.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
PCH eDP has many of the same needs as regular PCH DP connections,
including the DP_CTl bit settings, the TRANS_DP_CTL register.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
No persistent data was ever stored here, so link_status is instead
allocated on the stack as needed.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Every usage of PCH_PP_CONTROL sets the PANEL_UNLOCK_REGS value to
ensure that writes will be respected, move this to a common function
to make the driver cleaner.
No functional changes.
Signed-off-by: Keith Packard <keithp@keithp.com>
According to the gen6 docs, only the DP_A port (on-CPU eDP) still uses
the old IBX bit shift for the link training pattern setup bits.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
The obvious counterpart to is_pch_edp(). Convert existing instances of
the idiom to the new routine.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
DPCD 1.1+ adds some automated test infrastructure support. Add support
for reading the IRQ source and jumping to a test handling routine if
needed. Subsequent patches will handle particular tests; this patch
just ACKs any requested tests by default.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
Read link status first, followed by the full DPCD receiver cap field
rather than just the first 8 bytes.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
The previous code was confused about units, which is pretty reasonable
given that the units themselves are confusing.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
At the point where we check, we can't do much about the failure, but it
can aid debugging. Note that the auto-train override bit will be reset
as part of normal mode setting with this patch if a pipe ever does get
stuck, but that's consistent with the workaround for CPT provided by the
hardware team. This patch helped catch the fact that the pipe wasn't
running in the !composite sync FDI case on my IVB SDV, so has already
shown to be useful.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Well almost anyway. IVB has 3 planes, pipes, transcoders, and FDI
interfaces, but only 2 pipe PLLs. So two of the pipes must use the same
pipe timings (e.g. 2 DP plus one other, or two HDMI with the same mode
and one other, etc.).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
If the panel is powered up, there's no need to delay for the 'off'
interval when turning the panel on.
Signed-off-by: Keith Packard <keithp@keithp.com>
This eliminates a fairly long delay when power sequencing newer
hardware
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There's no good reason to turn off the eDP force VDD bit synchronously
while probing devices; that just sticks a huge delay into all mode
setting paths. Instead, queue a delayed work proc to disable the VDD
force bit and then remember when that fires to ensure that the
appropriate delay is respected before trying to turn it back on.
Signed-off-by: Keith Packard <keithp@keithp.com>
We need to check eDP VDD force and panel on in several places, so
create some simple helper functions to avoid duplicating code.
Signed-off-by: Keith Packard <keithp@keithp.com>
The return value was unused, so just stop doing that.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This value doesn't come directly from the VBT, and so is rather
specific to the particular DP output.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Store the panel power sequencing delays in the dp private structure,
rather than the global device structure. Who knows, maybe we'll get
more than one eDP device in the future.
From the eDP spec, we need the following numbers:
T1 + T3 Power on to Aux Channel operation (panel_power_up_delay)
This marks how long it takes the panel to boot up and
get ready to receive aux channel communications.
T8 Video signal to backlight on (backlight_on_delay)
Once a valid video signal is being sent to the device,
it can take a while before the panel is actuall
showing useful data. This delay allows the panel
to get something reasonable up before the backlight
is turned on.
T9 Backlight off to video off (backlight_off_delay)
Turning the backlight off can take a moment, so
this delay makes sure there is still valid video
data on the screen.
T10 Video off to power off (panel_power_down_delay)
Presumably this delay allows the panel to perform
an orderly shutdown of the display.
T11 + T12 Power off to power on (panel_power_cycle_delay)
So, once you turn the panel off, you have to wait a
while before you can turn it back on. This delay is
usually the longest in the entire sequence.
Neither the VBIOS source code nor the hardware documentation has a
clear mapping between the delay values they provide and those required
by the eDP spec. The VBIOS code actually uses two different labels for
the delay values in the five words of the relevant VBT table.
**** MORE LATER ***
Look at both the current hardware register settings and the VBT
specified panel power sequencing timings. Use the maximum of the two
delays, to make sure things work reliably. If there is no VBT data,
then those values will be initialized to zero, so we'll just use the
values as programmed in the hardware. Note that the BIOS just fetches
delays from the VBT table to place in the hardware registers, so we
should get the same values from both places, except for rounding.
VBT doesn't provide any values for T1 or T2, so we'll always just use
the hardware value for that.
The panel power up delay is thus T1 + T2 + T3, which should be
sufficient in all cases.
The panel power down delay is T1 + T2 + T12, using T1+T2 as a proxy
for T11, which isn't available anywhere.
For the backlight delays, the eDP spec says T6 + T8 is the delay from the
end of link training to backlight on and T9 is the delay from
backlight off until video off. The hardware provides a 'backlight on'
delay, which I'm taking to be T6 + T8 while the VBT provides something
called 'T7', which I'm assuming is s
On the macbook air I'm testing with, this yields a power-up delay of
over 200ms and a power-down delay of over 600ms. It all works now, but
we're frobbing these power controls several times during mode setting,
making the whole process take an awfully long time.
Signed-off-by: Keith Packard <keithp@keithp.com>
