To print stack entries into a buffer, users of stackdepot, first get a
list of stack entries using stack_depot_fetch and then print this list
into a buffer using stack_trace_snprint.  Provide a helper in stackdepot
for this purpose.  Also change above mentioned users to use this helper.

[imran.f.khan@oracle.com: fix build error]
  Link: https://lkml.kernel.org/r/20210915175321.3472770-4-imran.f.khan@oracle.com
[imran.f.khan@oracle.com: export stack_depot_snprint() to modules]
  Link: https://lkml.kernel.org/r/20210916133535.3592491-4-imran.f.khan@oracle.com

Link: https://lkml.kernel.org/r/20210915014806.3206938-4-imran.f.khan@oracle.comSigned-off-by: NImran Khan <imran.f.khan@oracle.com>
Suggested-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: Jani Nikula <jani.nikula@intel.com>	[i915]
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 2f015ec6 ("drm/dp_mst: Add sideband down request tracing +
selftests") added some debug code for sideband message tracing. But
it seems to have unintentionally changed the behavior on sideband message
failure. It catches and returns failure only if DRM_UT_DP is enabled.
Otherwise it ignores the error code and returns success. So on an MST
unplug, the caller is unaware that the clear payload message failed and
ends up waiting for 4 seconds for the response. Fixes the issue by
returning the proper error code.

Changes in V2:
-- Revise commit text as review comment
-- add Fixes text

Changes in V3:
-- remove "unlikely" optimization

Fixes: 2f015ec6 ("drm/dp_mst: Add sideband down request tracing + selftests")
Cc: <stable@vger.kernel.org> # v5.5+
Signed-off-by: NRajkumar Subbiah <rsubbia@codeaurora.org>
Signed-off-by: NKuogee Hsieh <khsieh@codeaurora.org>
Reviewed-by: NStephen Boyd <swboyd@chromium.org>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1625585434-9562-1-git-send-email-khsieh@codeaurora.org

Commit 3769e4c0 ("drm/dp_mst: Avoid to mess up payload table by
ports in stale topology") added to calls to drm_dbg_kms() but it
missed the first parameter, the drm device breaking the build.

Fixes: 3769e4c0 ("drm/dp_mst: Avoid to mess up payload table by ports in stale topology")
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616194415.36926-1-jose.souza@intel.com

[Why]
After unplug/hotplug hub from the system, userspace might start to
clear stale payloads gradually. If we call drm_dp_mst_deallocate_vcpi()
to release stale VCPI of those ports which are not relating to current
topology, we have chane to wrongly clear active payload table entry for
current topology.

E.g.
We have allocated VCPI 1 in current payload table and we call
drm_dp_mst_deallocate_vcpi() to clean VCPI 1 in stale topology. In
drm_dp_mst_deallocate_vcpi(), it will call drm_dp_mst_put_payload_id()
tp put VCPI 1 and which means ID 1 is available again. Thereafter, if we
want to allocate a new payload stream, it will find ID 1 is available by
drm_dp_mst_assign_payload_id(). However, ID 1 is being used

[How]
Check target sink is relating to current topology or not before doing
any payload table update.
Searching upward to find the target sink's relevant root branch device.
If the found root branch device is not the same root of current
topology, don't update payload table.

Changes since v1:
* Change debug macro to use drm_dbg_kms() instead
* Amend the commit message to add Cc tag.
Signed-off-by: NWayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616035501.3776-3-Wayne.Lin@amd.comReviewed-by: NLyude Paul <lyude@redhat.com>

[Why]
When we receive CSN message to notify one port is disconnected, we will
implicitly set its corresponding num_slots to 0. Later on, we will
eventually call drm_dp_update_payload_part1() to arrange down streams.

In drm_dp_update_payload_part1(), we iterate over all proposed_vcpis[]
to do the update. Not specific to a target sink only. For example, if we
light up 2 monitors, Monitor_A and Monitor_B, and then we unplug
Monitor_B. Later on, when we call drm_dp_update_payload_part1() to try
to update payload for Monitor_A, we'll also implicitly clean payload for
Monitor_B at the same time. And finally, when we try to call
drm_dp_update_payload_part1() to clean payload for Monitor_B, we will do
nothing at this time since payload for Monitor_B has been cleaned up
previously.

For StarTech 1to3 DP hub, it seems like if we didn't update DPCD payload
ID table then polling for "ACT Handled"(BIT_1 of DPCD 002C0h) will fail
and this polling will last for 3 seconds.

Therefore, guess the best way is we don't set the proposed_vcpi[]
diretly. Let user of these herlper functions to set the proposed_vcpi
directly.

[How]
1. Revert commit 7617e962 ("drm/dp_mst: clear time slots for ports
invalid")
2. Tackle the issue in previous commit by skipping those trasient
proposed VCPIs. These stale VCPIs shoulde be explicitly cleared by
user later on.

Changes since v1:
* Change debug macro to use drm_dbg_kms() instead
* Amend the commit message to add Fixed & Cc tags
Signed-off-by: NWayne Lin <Wayne.Lin@amd.com>
Fixes: 7617e962 ("drm/dp_mst: clear time slots for ports invalid")
Cc: Lyude Paul <lyude@redhat.com>
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.5+
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616035501.3776-2-Wayne.Lin@amd.comReviewed-by: NLyude Paul <lyude@redhat.com>

[why]
Link rate in kHz is what is eventually required to calculate the link
bandwidth, which makes kHz a more generic unit. This should also make
forward-compatibility with new DP standards easier.

[how]
- Replace 'link rate DPCD code' with 'link rate in kHz' when used with
drm_dp_mst_topology_mgr_init()
- Add/remove related DPCD code conversion from/to kHz where applicable
Signed-off-by: NNikola Cornij <nikola.cornij@amd.com>
Acked-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210512210011.8425-2-nikola.cornij@amd.com

[why]
DP 1.4a spec mandates that if DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is
set, Extended Base Receiver Capability DPCD space must be used. Without
doing that, the three DPCD values that differ will be wrong, leading to
incorrect or limited functionality. MST link rate, for example, could
have a lower value. Also, Synaptics quirk wouldn't work out well when
Extended DPCD was not read, resulting in no DSC for such hubs.

[how]
Modify MST topology manager to use the values from Extended DPCD where
applicable.

To prevent regression on the sources that have a lower maximum link rate
capability than MAX_LINK_RATE from Extended DPCD, have the drivers
supply maximum lane count and rate at initialization time.

This also reverts commit 2dcab875 ("Revert drm/dp_mst: Retrieve
extended DPCD caps for topology manager"), brining the change back to the
original commit ad44c032 ("drm/dp_mst: Retrieve extended DPCD caps for
topology manager").
Signed-off-by: NNikola Cornij <nikola.cornij@amd.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210429221151.22020-2-nikola.cornij@amd.com

And finally, convert all of the code in drm_dp_mst_topology.c over to using
drm_err() and drm_dbg*(). Note that this refactor would have been a lot
more complicated to have tried writing a coccinelle script for, so this
whole thing was done by hand.

v2:
* Fix line-wrapping in drm_dp_mst_atomic_check_mstb_bw_limit()
Signed-off-by: NLyude Paul <lyude@redhat.com>
Cc: Robert Foss <robert.foss@linaro.org>
Reviewed-by: NRobert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-18-lyude@redhat.comReviewed-by: NDave Airlie <airlied@redhat.com>

Since this is one of the few functions in drm_dp_mst_topology.c that
doesn't have any way of getting access to a drm_device, let's pass the
drm_dp_mst_topology_mgr down to this function so that it can use
drm_dbg_kms().
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-14-lyude@redhat.comReviewed-by: NDave Airlie <airlied@redhat.com>

This is something that we've wanted for a while now: the ability to
actually look up the respective drm_device for a given drm_dp_aux struct.
This will also allow us to transition over to using the drm_dbg_*() helpers
for debug message printing, as we'll finally have a drm_device to reference
for doing so.

Note that there is one limitation with this - because some DP AUX adapters
exist as platform devices which are initialized independently of their
respective DRM devices, one cannot rely on drm_dp_aux->drm_dev to always be
non-NULL until drm_dp_aux_register() has been called. We make sure to point
this out in the documentation for struct drm_dp_aux.

v3:
* Add WARN_ON_ONCE() to drm_dp_aux_register() if drm_dev isn't filled out
Signed-off-by: NLyude Paul <lyude@redhat.com>
Acked-by: NThierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210423184309.207645-4-lyude@redhat.comReviewed-by: NDave Airlie <airlied@redhat.com>

Checkpatch was complaining about this - there's no need for us to print
errors when kzalloc() fails, as kzalloc() will already WARN for us. So,
let's fix that before converting things to make checkpatch happy.
Signed-off-by: NLyude Paul <lyude@redhat.com>
Cc: Robert Foss <robert.foss@linaro.org>
Reviewed-by: NRobert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210326203807.105754-20-lyude@redhat.com

[why]
MST topology print was missing fec logging and pdt printed
as an int wasn't clear. vcpi and payload info was printed as an
arbitrary series of ints which requires user to know the ordering
of the prints, making the logs difficult to use.

[how]
-add fec logging
-add pdt parsing into strings
-format vcpi and payload info into tables with headings
-clean up topology prints
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NEryk Brol <eryk.brol@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210325180614.37060-1-eryk.brol@amd.com

[Why & How]
According to DP spec, CLEAR_PAYLOAD_ID_TABLE is a path broadcast request
message and current implementation is incorrect. Fix it.
Signed-off-by: NWayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210224101521.6713-3-Wayne.Lin@amd.com

[Why & How]
According to DP spec, broadcast message LCT equals to 1 and LCR equals
to 6. Current implementation is incorrect. Fix it.
In addition, revise a bit the hdr->rad handling to include broadcast
case.
Signed-off-by: NWayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210224101521.6713-2-Wayne.Lin@amd.com

It's possible to modeset a connector/mst port that has a 0 full_pbn
value: if the sink on the port deasserts its HPD and a branch device
reports this via a CSN with the port's ddps=0 and pdt!=NONE the driver
clears full_pbn, but the corresponding connector can be still
modesetted.

This happened on a DELL U2719D monitor as the branch device and an LG
27UL650-W daisy-chained to it, the LG monitor generating a long HPD
pulse (doing this for some reason always when waking up from some power
saving state).

Tune down the WARN about this scenario to a debug message.

v2: Use the correct atomic debug message level. (Lyude)

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1917
Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210216123448.410545-1-imre.deak@intel.com

Caching EDIDs for physical ports prevents updating the EDID if a port
gets reconnected via a Connection Status Notification message, fix this.

Fixes: db1a0795 ("drm/dp_mst: Handle SST-only branch device case")
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201120145.350258-2-imre.deak@intel.com
(cherry picked from commit 46809153)
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>

Use the macro defined for the first logical port instead of the
corresponding magic number.

Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201120145.350258-4-imre.deak@intel.com

drm_get_edid() already updates the tile property since
commit 2de3a078 ("drm/dp: Set the connector's TILE property even for DP SST connectors")
so no need to update it after calling this function.

Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201120145.350258-3-imre.deak@intel.com

Caching EDIDs for physical ports prevents updating the EDID if a port
gets reconnected via a Connection Status Notification message, fix this.

Fixes: db1a0795 ("drm/dp_mst: Handle SST-only branch device case")
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201120145.350258-2-imre.deak@intel.com

Reporting a port as connected if nothing is attached to them leads to
any i2c transactions on this port trying to use an uninitialized i2c
adapter, fix this.

Let's account for this case even if branch devices have no good reason
to report a port as plugged with their peer device type set to 'none'.

Fixes: db1a0795 ("drm/dp_mst: Handle SST-only branch device case")
References: https://gitlab.freedesktop.org/drm/intel/-/issues/2987
References: https://gitlab.freedesktop.org/drm/intel/-/issues/1963
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: <stable@vger.kernel.org> # v5.5+
Cc: intel-gfx@lists.freedesktop.org
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Reported-by: NThiago Macieira <gitlab@gitlab.freedesktop.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201120145.350258-1-imre.deak@intel.com

This function will be needed by the next patch where the driver
calculates the BW based on driver specific parameters, so export it.

At the same time sanitize the function params, passing the more natural
link rate instead of the encoding of the same rate.

v2:
- Fix function documentation. (Lyude)

Cc: Lyude Paul <lyude@redhat.com>
Cc: Ville Syrjala <ville.syrjala@intel.com>
Cc: <stable@vger.kernel.org>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210125173636.1733812-1-imre.deak@intel.com
(cherry picked from commit a321fc2b)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

This function will be needed by the next patch where the driver
calculates the BW based on driver specific parameters, so export it.

At the same time sanitize the function params, passing the more natural
link rate instead of the encoding of the same rate.

v2:
- Fix function documentation. (Lyude)

Cc: Lyude Paul <lyude@redhat.com>
Cc: Ville Syrjala <ville.syrjala@intel.com>
Cc: <stable@vger.kernel.org>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210125173636.1733812-1-imre.deak@intel.com

This reverts commit 0883ce81. Originally
these quirks were added because of the issues with using the eDP
backlight interfaces on certain laptop panels, which made it impossible
to properly probe for DPCD backlight support without having a whitelist
for panels that we know have working VESA backlight control interfaces
over DPCD. As well, it should be noted it was impossible to use the
normal sink OUI for recognizing these panels as none of them actually
filled out their OUIs, hence needing to resort to checking EDIDs.

At the time we weren't really sure why certain panels had issues with
DPCD backlight controls, but we eventually figured out that there was a
second interface that these problematic laptop panels actually did work
with and advertise properly: Intel's proprietary backlight interface for
HDR panels. So far the testing we've done hasn't brought any panels to
light that advertise this interface and don't support it properly, which
means we finally have a real solution to this problem.

As a result, we now have no need for the force DPCD backlight quirk, and
furthermore this also removes the need for any kind of EDID quirk
checking in DRM. So, let's just revert it for now since we were the only
driver using this.

v3:
* Rebase
v2:
* Fix indenting error picked up by checkpatch in
  intel_edp_init_connector()
Signed-off-by: NLyude Paul <lyude@redhat.com>
Acked-by: NJani Nikula <jani.nikula@intel.com>
Cc: thaytan@noraisin.net
Cc: Vasily Khoruzhick <anarsoul@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210114221709.2261452-6-lyude@redhat.com

drm_dp_check_and_send_link_address discovers MST device topology. It can
return both positive and negative values. When it returns positive
values there is no error found. If it returns negative values there is
error found, such as get NAK , timeout, etc. Following
drm_kms_helper_hotplug_event should be called when
drm_dp_check_and_send_link_address returns positive value.
Signed-off-by: NXiaogang Chen <xiaogang.chen@amd.com>
Acked-by: NSimon Ser <contact@emersion.fr>
Signed-off-by: Simon Ser <contact@emersion.fr> (re-formatted commit message)
Link: https://patchwork.freedesktop.org/patch/msgid/DM6PR12MB2602B6281BF8C9430115E03BE3AA0@DM6PR12MB2602.namprd12.prod.outlook.com

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/drm_dp_mst_topology.c: In function ‘drm_dp_send_query_stream_enc_status’:
 drivers/gpu/drm/drm_dp_mst_topology.c:3263:6: warning: variable ‘len’ set but not used [-Wunused-but-set-variable]

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201116174112.1833368-4-lee.jones@linaro.org

This reverts commit ad44c032.

Currently DRM driver assume the source device caps is higher than the MST device
caps. With this commit, this statement would be broken.

e.g. the source device only support DP1.2 and the mst device support DP1.4.
Signed-off-by: NKoba Ko <koba.ko@canonical.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103034907.72129-1-koba.ko@canonical.com

As per DP-1.3, First check DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT.
If DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is 1,read the DP_DP13_DPCD_REV to
get the faster capability.
If DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is 0,read DP_DPCD_REV.
Signed-off-by: NKoba Ko <koba.ko@canonical.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
[added aux name to drm_dbg_kms() call]
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200922065313.4794-1-koba.ko@canonical.com

For DP MST outputs, the i2c device currently only supports transfers
that can be implemented using remote i2c reads. Such transfers must
consist of zero or more write transactions followed by one read
transaction. DDC/CI commands require standalone write transactions and
hence aren't supported.

Since each remote i2c write is handled as a separate transfer, remote
i2c writes can support transfers consisting of write transactions, where
all but the last have I2C_M_STOP set. According to the DDC/CI 1.1
standard, DDC/CI commands only require a single write or read
transaction in a transfer, so this is sufficient.

For i2c transfers meeting the above criteria, generate and send a remote
i2c write message for each transaction. Add the trivial remote i2c write
reply parsing support so remote i2c write acks bubble up correctly.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/37Signed-off-by: NSam McNally <sammc@chromium.org>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200727160225.1.I4e95a534de051551cd143e6cb83d4c5a9b0ad1cd@changeid

Used to query whether an MST stream is encrypted or not.

Cc: Lyude Paul <lyude@redhat.com>
Reviewed-by: NAnshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NSean Paul <seanpaul@chromium.org>

Link: https://patchwork.freedesktop.org/patch/msgid/20200218220242.107265-14-sean@poorly.run #v4
Link: https://patchwork.freedesktop.org/patch/msgid/20200305201236.152307-15-sean@poorly.run #v5
Link: https://patchwork.freedesktop.org/patch/msgid/20200429195502.39919-15-sean@poorly.run #v6
Link: https://patchwork.freedesktop.org/patch/msgid/20200623155907.22961-16-sean@poorly.run #v7
Link: https://patchwork.freedesktop.org/patch/msgid/20200818153910.27894-16-sean@poorly.run #v8

Changes in v4:
-Added to the set
Changes in v5:
-None
Changes in v6:
-Use FIELD_PREP to generate request buffer bitfields (Lyude)
-Add mst selftest and dump/decode_sideband_req for QSES (Lyude)
Changes in v7:
-None
Changes in v8:
-Reverse the parsing on the hdcp_*x_device_present bits and leave
 breadcrumb in case this is incorrect (Anshuman)
Changes in v8.5:
-s/DRM_DEBUG_KMS/drm_dbg_kms/ (Lyude)
Signed-off-by: NRamalingam C <ramalingam.c@intel.com>
Acked-by: NDaniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200819143133.46232-1-sean@poorly.run

Just a tiny drive-by cleanup, we can consolidate i915's code for
checking for MST support into a helper to be shared across drivers.

v5:
* Drop !!()
* Move drm_dp_has_mst() out of header
* Change name from drm_dp_has_mst() to drm_dp_read_mst_cap()
Signed-off-by: NLyude Paul <lyude@redhat.com>
Reviewed-by: NSean Paul <sean@poorly.run>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826182456.322681-10-lyude@redhat.com

[Why]
In certain cases the crtc can be NULL and returning -EINVAL causes
atomic check to fail when it shouln't. This leads to valid
configurations failing because atomic check fails.

[How]
Don't early return if crtc is null
Signed-off-by: NBhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
[added stable cc]
Signed-off-by: NLyude Paul <lyude@redhat.com>
Fixes: 8ec04671 ("drm/dp_mst: Add helper to trigger modeset on affected DSC MST CRTCs")
Cc: <stable@vger.kernel.org> # v5.6+
Link: https://patchwork.freedesktop.org/patch/msgid/20200814170140.24917-1-Bhawanpreet.Lakha@amd.com

drm_dp_mst_allocate_vcpi() invokes
drm_dp_mst_topology_get_port_validated(), which increases the refcount
of the "port".

These reference counting issues take place in two exception handling
paths separately. Either when “slots” is less than 0 or when
drm_dp_init_vcpi() returns a negative value, the function forgets to
reduce the refcnt increased drm_dp_mst_topology_get_port_validated(),
which results in a refcount leak.

Fix these issues by pulling up the error handling when "slots" is less
than 0, and calling drm_dp_mst_topology_put_port() before termination
when drm_dp_init_vcpi() returns a negative value.

Fixes: 1e797f55 ("drm/dp: Split drm_dp_mst_allocate_vcpi")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: NXiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: NXin Tan <tanxin.ctf@gmail.com>
Signed-off-by: NXin Xiong <xiongx18@fudan.edu.cn>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200719154545.GA41231@xin-virtual-machine

Resolve checkpatch issues for missing blank lines after declarations.
Issues found in multiple files with checkpatch.pl.
Signed-off-by: NSuraj Upadhyay <usuraj35@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702131749.GA25710@blackclown

Atm, a pending delayed destroy work during module removal will be
canceled, leaving behind MST ports, mstbs. Fix this by using a dedicated
workqueue which will be drained of requeued items as well when
destroying it.

v2:
- Check if wq is NULL before calling destroy_workqueue().

Cc: Lyude Paul <lyude@redhat.com>
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: NStanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200610134704.25270-1-imre.deak@intel.com

During the initial MST probing an MST port's I2C device will be
registered using the kdev of the DRM device as a parent. Later after MST
Connection Status Notifications this I2C device will be re-registered
with the kdev of the port's connector. This will also move
inconsistently the I2C device's sysfs entry from the DRM device's sysfs
dir to the connector's dir.

Fix the above by keeping the DRM kdev as the parent of the I2C device.

Ideally the connector's kdev would be used as a parent, similarly to
non-MST connectors, however that needs some more refactoring to ensure
the connector's kdev is already available early enough. So keep the
existing (initial) behavior for now.

Cc: <stable@vger.kernel.org>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NStanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200607212522.16935-2-imre.deak@intel.com

The WARN below triggers during the removal of an MST port. The problem
is that the parent device's (the connector's kdev) sysfs directory is
removed recursively when the connector is unregistered (even though the
I2C device holds a reference on the parent device). To fix this set
first the Peer Device Type to none which will remove the I2C device.

Note that atm, inconsistently, the parent of the I2C device is initially set to
the DRM kdev and after a Connection Status Notification the parent may be reset
to be the connector's kdev. This problem is addressed by the next patch.

[ 4462.989299] ------------[ cut here ]------------
[ 4463.014940] sysfs group 'power' not found for kobject 'i2c-24'
[ 4463.034664] WARNING: CPU: 0 PID: 970 at fs/sysfs/group.c:281 sysfs_remove_group+0x71/0x80
[ 4463.044357] Modules linked in: snd_hda_intel i915 drm_kms_helper(O) drm netconsole snd_hda_codec_hdmi mei_hdcp x86_pkg_temp_thermal coretemp crct10dif_pclmul snd_intel_dspcf
g crc32_pclmul snd_hda_codec snd_hwdep ghash_clmulni_intel snd_hda_core asix usbnet kvm_intel mii i2c_algo_bit snd_pcm syscopyarea sysfillrect e1000e sysimgblt fb_sys_fops prim
e_numbers ptp pps_core i2c_i801 r8169 mei_me realtek mei [last unloaded: drm]
[ 4463.044399] CPU: 0 PID: 970 Comm: kworker/0:2 Tainted: G           O      5.7.0+ #172
[ 4463.044402] Hardware name: Intel Corporation Tiger Lake Client Platform/TigerLake U DDR4 SODIMM RVP
[ 4463.044423] Workqueue: events drm_dp_delayed_destroy_work [drm_kms_helper]
[ 4463.044428] RIP: 0010:sysfs_remove_group+0x71/0x80
[ 4463.044431] Code: 48 89 df 5b 5d 41 5c e9 cd b6 ff ff 48 89 df e8 95 b4 ff ff eb cb 49 8b 14 24 48 8b 75 00 48 c7 c7 20 0f 3f 82 e8 9f c5 d7 ff <0f> 0b 5b 5d 41 5c c3 0f 1f
84 00 00 00 00 00 48 85 f6 74 31 41 54
[ 4463.044433] RSP: 0018:ffffc900018bfbf0 EFLAGS: 00010282
[ 4463.044436] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
[ 4463.044439] RDX: 0000000080000001 RSI: ffff88849e828f38 RDI: 00000000ffffffff
[ 4463.052970] [drm:drm_atomic_get_plane_state [drm]] Added [PLANE:100:plane 2B] 00000000c2160caa state to 00000000d172564a
[ 4463.070533] RBP: ffffffff820cea20 R08: ffff88847f4b8958 R09: 0000000000000000
[ 4463.070535] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88848a725018
[ 4463.070537] R13: 0000000000000000 R14: ffffffff827090e0 R15: 0000000000000002
[ 4463.070539] FS:  0000000000000000(0000) GS:ffff88849e800000(0000) knlGS:0000000000000000
[ 4463.070541] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4463.070543] CR2: 00007fdf8a756538 CR3: 0000000489684001 CR4: 0000000000760ef0
[ 4463.070545] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 4463.070547] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 4463.070549] PKRU: 55555554
[ 4463.070551] Call Trace:
[ 4463.070560]  device_del+0x84/0x400
[ 4463.070571]  cdev_device_del+0x10/0x30
[ 4463.070578]  put_i2c_dev+0x69/0x80
[ 4463.070584]  i2cdev_detach_adapter+0x2e/0x60
[ 4463.070591]  notifier_call_chain+0x34/0x90
[ 4463.070599]  blocking_notifier_call_chain+0x3f/0x60
[ 4463.070606]  device_del+0x7c/0x400
[ 4463.087817]  ? lockdep_init_map_waits+0x57/0x210
[ 4463.087825]  device_unregister+0x11/0x60
[ 4463.087829]  i2c_del_adapter+0x249/0x310
[ 4463.087846]  drm_dp_port_set_pdt+0x6b/0x2c0 [drm_kms_helper]
[ 4463.087862]  drm_dp_delayed_destroy_work+0x2af/0x350 [drm_kms_helper]
[ 4463.087876]  process_one_work+0x268/0x600
[ 4463.105438]  ? __schedule+0x30c/0x920
[ 4463.105451]  worker_thread+0x37/0x380
[ 4463.105457]  ? process_one_work+0x600/0x600
[ 4463.105462]  kthread+0x140/0x160
[ 4463.105466]  ? kthread_park+0x80/0x80
[ 4463.105474]  ret_from_fork+0x24/0x50

Cc: <stable@vger.kernel.org>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NStanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200607212522.16935-1-imre.deak@intel.com

Some TypeC -> native DP adapters, at least the Club 3D CAC-1557 adapter,
incorrectly filter out HPD short pulses with a duration less than
~540 usec, leading to MST probe failures.

According to the DP Standard 2.0 section 5.1.4:
- DP sinks should generate short pulses in the 500 usec -> 1 msec range
- DP sources should detect short pulses in the 250 usec -> 2 msec range

According to the DP Alt Mode on TypeC Standard section 3.9.2, adapters
should detect and forward short pulses according to how sources should
detect them as specified in the DP Standard (250 usec -> 2 msec).

Based on the above filtering out short pulses with a duration less than
540 usec is incorrect.

To make such adapters work add support for a driver polling on MST
inerrupt flags, and wire this up in the i915 driver. The sink can clear
an interrupt it raised after 110 msec if the source doesn't respond, so
use a 50 msec poll period to avoid missing an interrupt. Polling of the
MST interrupt flags is explicitly allowed by the DP Standard.

This fixes MST probe failures I saw using this adapter and a DELL U2515H
monitor.

v2:
- Fix the wait event timeout for the no-poll case.
v3 (Ville):
- Fix the short pulse duration limits in the commit log prescribed by the
  DP Standard.
- Add code comment explaining why/how polling is used.
- Factor out a helper to schedule the port's hpd irq handler and move it
  to the rest of hotplug handlers.
- Document the new MST callback.
- s/update_hpd_irq_state/poll_hpd_irq/

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200604184500.23730-2-imre.deak@intel.com

Make the locking look symmetric with the unlocking.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200603211040.8190-2-imre.deak@intel.com

drivers/gpu/drm/drm_dp_mst_topology.c:2898:6: warning: symbol 'drm_dp_send_clear_payload_id_table' was not declared. Should it be static?
drivers/gpu/drm/drm_dp_mst_topology.c:5451:37: warning: missing braces around initializer
drivers/gpu/drm/drm_dp_mst_topology.c:5451:37: warning: missing braces around initializer
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200516212330.13633-4-chris@chris-wilson.co.uk

This fixes the following use-after-free problem in case an MST down
message times out, while waiting for the response for it:

[  449.022841] [drm:drm_dp_mst_wait_tx_reply.isra.26] timedout msg send 0000000080ba7fa2 2 0
[  449.022898] ------------[ cut here ]------------
[  449.022903] list_add corruption. prev->next should be next (ffff88847dae32c0), but was 6b6b6b6b6b6b6b6b. (prev=ffff88847db1c140).
[  449.022931] WARNING: CPU: 2 PID: 22 at lib/list_debug.c:28 __list_add_valid+0x4d/0x70
[  449.022935] Modules linked in: asix usbnet mii snd_hda_codec_hdmi mei_hdcp i915 x86_pkg_temp_thermal coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hwdep e1000e snd_hda_core ptp snd_pcm pps_core mei_me mei intel_lpss_pci prime_numbers
[  449.022966] CPU: 2 PID: 22 Comm: kworker/2:0 Not tainted 5.7.0-rc3-CI-Patchwork_17536+ #1
[  449.022970] Hardware name: Intel Corporation Tiger Lake Client Platform/TigerLake U DDR4 SODIMM RVP, BIOS TGLSFWI1.R00.2457.A16.1912270059 12/27/2019
[  449.022976] Workqueue: events_long drm_dp_mst_link_probe_work
[  449.022982] RIP: 0010:__list_add_valid+0x4d/0x70
[  449.022987] Code: c3 48 89 d1 48 c7 c7 f0 e7 32 82 48 89 c2 e8 3a 49 b7 ff 0f 0b 31 c0 c3 48 89 c1 4c 89 c6 48 c7 c7 40 e8 32 82 e8 23 49 b7 ff <0f> 0b 31 c0 c3 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 90 e8 32 82 e8
[  449.022991] RSP: 0018:ffffc900001abcb0 EFLAGS: 00010286
[  449.022995] RAX: 0000000000000000 RBX: ffff88847dae2d58 RCX: 0000000000000001
[  449.022999] RDX: 0000000080000001 RSI: ffff88849d914978 RDI: 00000000ffffffff
[  449.023002] RBP: ffff88847dae32c0 R08: ffff88849d914978 R09: 0000000000000000
[  449.023006] R10: ffffc900001abcb8 R11: 0000000000000000 R12: ffff888490d98400
[  449.023009] R13: ffff88847dae3230 R14: ffff88847db1c140 R15: ffff888490d98540
[  449.023013] FS:  0000000000000000(0000) GS:ffff88849ff00000(0000) knlGS:0000000000000000
[  449.023017] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  449.023021] CR2: 00007fb96fafdc63 CR3: 0000000005610004 CR4: 0000000000760ee0
[  449.023025] PKRU: 55555554
[  449.023028] Call Trace:
[  449.023034]  drm_dp_queue_down_tx+0x59/0x110
[  449.023041]  ? rcu_read_lock_sched_held+0x4d/0x80
[  449.023050]  ? kmem_cache_alloc_trace+0x2a6/0x2d0
[  449.023060]  drm_dp_send_link_address+0x74/0x870
[  449.023065]  ? __slab_free+0x3e1/0x5c0
[  449.023071]  ? lockdep_hardirqs_on+0xe0/0x1c0
[  449.023078]  ? lockdep_hardirqs_on+0xe0/0x1c0
[  449.023097]  drm_dp_check_and_send_link_address+0x9a/0xc0
[  449.023106]  drm_dp_mst_link_probe_work+0x9e/0x160
[  449.023117]  process_one_work+0x268/0x600
[  449.023124]  ? __schedule+0x307/0x8d0
[  449.023139]  worker_thread+0x37/0x380
[  449.023149]  ? process_one_work+0x600/0x600
[  449.023153]  kthread+0x140/0x160
[  449.023159]  ? kthread_park+0x80/0x80
[  449.023169]  ret_from_fork+0x24/0x50

Fixes: d308a881 ("drm/dp_mst: Kill the second sideband tx slot, save the world")
Cc: Lyude Paul <lyude@redhat.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: <stable@vger.kernel.org> # v3.17+
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513103155.12336-1-imre.deak@intel.com