linux-stable.git/drivers/gpu/drm/display, branch linux-6.16.y Linux kernel stable tree drm/dp: Add an EDID quirk for the DPCD register access probe 2025-09-19T14:37:33+00:00 Imre Deak imre.deak@intel.com 2025-06-09T12:55:55+00:00 016760c555934609e852399899cac22712a280d8 commit b87ed522b3643f096ef183ed0ccf2d2b90ddd513 upstream. Reading DPCD registers has side-effects and some of these can cause a problem for instance during link training. Based on this it's better to avoid the probing quirk done before each DPCD register read, limiting this to the monitor which requires it. Add an EDID quirk for this. Leave the quirk enabled by default, allowing it to be disabled after the monitor is detected. v2: Fix lockdep wrt. drm_dp_aux::hw_mutex when calling drm_dp_dpcd_set_probe_quirk() with a dependent lock already held. v3: Add a helper for determining if DPCD probing is needed. (Jani) v4: - s/drm_dp_dpcd_set_probe_quirk/drm_dp_dpcd_set_probe (Jani) - Fix documentation of drm_dp_dpcd_set_probe(). - Add comment at the end of internal quirk entries. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://lore.kernel.org/r/20250609125556.109538-1-imre.deak@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b87ed522b3643f096ef183ed0ccf2d2b90ddd513 upstream.

Reading DPCD registers has side-effects and some of these can cause a
problem for instance during link training. Based on this it's better to
avoid the probing quirk done before each DPCD register read, limiting
this to the monitor which requires it. Add an EDID quirk for this. Leave
the quirk enabled by default, allowing it to be disabled after the
monitor is detected.

v2: Fix lockdep wrt. drm_dp_aux::hw_mutex when calling
    drm_dp_dpcd_set_probe_quirk() with a dependent lock already held.
v3: Add a helper for determining if DPCD probing is needed. (Jani)
v4:
- s/drm_dp_dpcd_set_probe_quirk/drm_dp_dpcd_set_probe (Jani)
- Fix documentation of drm_dp_dpcd_set_probe().
- Add comment at the end of internal quirk entries.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250609125556.109538-1-imre.deak@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/dp: Change AUX DPCD probe address from LANE0_1_STATUS to TRAINING_PATTERN_SET 2025-09-09T17:02:35+00:00 Imre Deak imre.deak@intel.com 2025-07-08T21:23:31+00:00 0fe5997644db7b8abdda13e1cfd0a816220c1710 commit d34d6feaf4a76833effcec0b148b65946b04cde8 upstream. Commit a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") stopped using the DPCD_REV register for DPCD probing, since this results in link training failures at least when using an Intel Barlow Ridge TBT hub at UHBR link rates (the DP_INTRA_HOP_AUX_REPLY_INDICATION never getting cleared after the failed link training). Since accessing DPCD_REV during link training is prohibited by the DP Standard, LANE0_1_STATUS (0x202) was used instead, as it falls within the Standard's valid register address range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) and it fixed the link training on the above TBT hub. However, reading the LANE0_1_STATUS register also has a side-effect at least on a Novatek eDP panel, as reported on the Closes: link below, resulting in screen flickering on that panel. One clear side-effect when doing the 1-byte probe reads from LANE0_1_STATUS during link training before reading out the full 6 byte link status starting at the same address is that the panel will report the link training as completed with voltage swing 0. This is different from the normal, flicker-free scenario when no DPCD probing is done, the panel reporting the link training complete with voltage swing 2. Using the TRAINING_PATTERN_SET register for DPCD probing doesn't have the above side-effect, the panel will link train with voltage swing 2 as expected and it will stay flicker-free. This register is also in the above valid register range and is unlikely to have a side-effect as that of LANE0_1_STATUS: Reading LANE0_1_STATUS is part of the link training CR/EQ sequences and so it may cause a state change in the sink - even if inadvertently as I suspect in the case of the above Novatek panel. As opposed to this, reading TRAINING_PATTERN_SET is not part of the link training sequence (it must be only written once at the beginning of the CR/EQ sequences), so it's unlikely to cause any state change in the sink. As a side-note, this Novatek panel also lacks support for TPS3, while claiming support for HBR2, which violates the DP Standard (the Standard mandating TPS3 for HBR2). Besides the Novatek panel (PSR 1), which this change fixes, I also verified the change on a Samsung (PSR 1) and an Analogix (PSR 2) eDP panel as well as on the Intel Barlow Ridge TBT hub. Note that in the drm-tip tree (targeting the v6.17 kernel version) the i915 and xe drivers keep DPCD probing enabled only for the panel known to require this (HP ZR24w), hence those drivers in drm-tip are not affected by the above problem. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Fixes: a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") Reported-and-tested-by: Paul Menzel <pmenzel@molgen.mpg.de> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558 Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://lore.kernel.org/r/20250708212331.112898-1-imre.deak@intel.com (cherry picked from commit bba9aa41654036534d86b198f5647a9ce15ebd7f) [Imre: Rebased on drm-intel-fixes] Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> [Rodrigo: Changed original commit hash to match with the one propagated in fixes] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit d34d6feaf4a76833effcec0b148b65946b04cde8 upstream.

Commit a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from
DPCD_REV to LANE0_1_STATUS") stopped using the DPCD_REV register for
DPCD probing, since this results in link training failures at least when
using an Intel Barlow Ridge TBT hub at UHBR link rates (the
DP_INTRA_HOP_AUX_REPLY_INDICATION never getting cleared after the failed
link training). Since accessing DPCD_REV during link training is
prohibited by the DP Standard, LANE0_1_STATUS (0x202) was used instead,
as it falls within the Standard's valid register address range
(0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) and it fixed the link
training on the above TBT hub.

However, reading the LANE0_1_STATUS register also has a side-effect at
least on a Novatek eDP panel, as reported on the Closes: link below,
resulting in screen flickering on that panel. One clear side-effect when
doing the 1-byte probe reads from LANE0_1_STATUS during link training
before reading out the full 6 byte link status starting at the same
address is that the panel will report the link training as completed
with voltage swing 0. This is different from the normal, flicker-free
scenario when no DPCD probing is done, the panel reporting the link
training complete with voltage swing 2.

Using the TRAINING_PATTERN_SET register for DPCD probing doesn't have
the above side-effect, the panel will link train with voltage swing 2 as
expected and it will stay flicker-free. This register is also in the
above valid register range and is unlikely to have a side-effect as that
of LANE0_1_STATUS: Reading LANE0_1_STATUS is part of the link training
CR/EQ sequences and so it may cause a state change in the sink - even if
inadvertently as I suspect in the case of the above Novatek panel. As
opposed to this, reading TRAINING_PATTERN_SET is not part of the link
training sequence (it must be only written once at the beginning of the
CR/EQ sequences), so it's unlikely to cause any state change in the
sink.

As a side-note, this Novatek panel also lacks support for TPS3, while
claiming support for HBR2, which violates the DP Standard (the Standard
mandating TPS3 for HBR2).

Besides the Novatek panel (PSR 1), which this change fixes, I also
verified the change on a Samsung (PSR 1) and an Analogix (PSR 2) eDP
panel as well as on the Intel Barlow Ridge TBT hub.

Note that in the drm-tip tree (targeting the v6.17 kernel version) the
i915 and xe drivers keep DPCD probing enabled only for the panel known
to require this (HP ZR24w), hence those drivers in drm-tip are not
affected by the above problem.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Fixes: a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS")
Reported-and-tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250708212331.112898-1-imre.deak@intel.com
(cherry picked from commit bba9aa41654036534d86b198f5647a9ce15ebd7f)
[Imre: Rebased on drm-intel-fixes]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[Rodrigo: Changed original commit hash to match with the one propagated in fixes]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS" 2025-09-04T14:55:52+00:00 Imre Deak imre.deak@intel.com 2025-08-28T17:49:29+00:00 05981233cf2e62f4ee20009d586a96abc06e87af This reverts commit 944e732be9c3a33e64e9fb0f5451a37fc252ddfc which is commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f upstream. The upstream commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") the reverted commit backported causes a regression, on one eDP panel at least resulting in display flickering, described in detail at the Link: below. The issue fixed by the upstream commit will need a different solution, revert the backport for now. Cc: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Cc: Sasha Levin <sashal@kernel.org> Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558 Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
This reverts commit 944e732be9c3a33e64e9fb0f5451a37fc252ddfc which is
commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f upstream.

The upstream commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f ("drm/dp:
Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") the
reverted commit backported causes a regression, on one eDP panel at
least resulting in display flickering, described in detail at the Link:
below. The issue fixed by the upstream commit will need a different
solution, revert the backport for now.

Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: Sasha Levin <sashal@kernel.org>
Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS 2025-08-28T14:34:39+00:00 Imre Deak imre.deak@intel.com 2025-08-23T12:56:25+00:00 944e732be9c3a33e64e9fb0f5451a37fc252ddfc [ Upstream commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f ] Reading DPCD registers has side-effects in general. In particular accessing registers outside of the link training register range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly forbidden by the DP v2.1 Standard, see 3.6.5.1 DPTX AUX Transaction Handling Mandates 3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates Based on my tests, accessing the DPCD_REV register during the link training of an UHBR TBT DP tunnel sink leads to link training failures. Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the DPCD register access quirk. Cc: <stable@vger.kernel.org> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com [ DP_TRAINING_PATTERN_SET => DP_LANE0_1_STATUS ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f ]

Reading DPCD registers has side-effects in general. In particular
accessing registers outside of the link training register range
(0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly
forbidden by the DP v2.1 Standard, see

3.6.5.1 DPTX AUX Transaction Handling Mandates
3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates

Based on my tests, accessing the DPCD_REV register during the link
training of an UHBR TBT DP tunnel sink leads to link training failures.

Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the
DPCD register access quirk.

Cc: <stable@vger.kernel.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com
[ DP_TRAINING_PATTERN_SET => DP_LANE0_1_STATUS ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/connector: hdmi: Evaluate limited range after computing format 2025-08-15T14:38:36+00:00 Cristian Ciocaltea cristian.ciocaltea@collabora.com 2025-05-27T12:11:09+00:00 c5b9234edbcc7af306b3d8b67aa9732705f2761b [ Upstream commit 21f627139652dd8329a88e281df6600f3866d238 ] Evaluating the requirement to use a limited RGB quantization range involves a verification of the output format, among others, but this is currently performed before actually computing the format, hence relying on the old connector state. Move the call to hdmi_is_limited_range() after hdmi_compute_config() to ensure the verification is done on the updated output format. Fixes: 027d43590649 ("drm/connector: hdmi: Add RGB Quantization Range to the connector state") Reviewed-by: Dmitry Baryshkov <lumag@kernel.org> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com> Acked-by: Maxime Ripard <mripard@kernel.org> Link: https://lore.kernel.org/r/20250527-hdmi-conn-yuv-v5-1-74c9c4a8ac0c@collabora.com Signed-off-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 21f627139652dd8329a88e281df6600f3866d238 ]

Evaluating the requirement to use a limited RGB quantization range
involves a verification of the output format, among others, but this is
currently performed before actually computing the format, hence relying
on the old connector state.

Move the call to hdmi_is_limited_range() after hdmi_compute_config() to
ensure the verification is done on the updated output format.

Fixes: 027d43590649 ("drm/connector: hdmi: Add RGB Quantization Range to the connector state")
Reviewed-by: Dmitry Baryshkov <lumag@kernel.org>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250527-hdmi-conn-yuv-v5-1-74c9c4a8ac0c@collabora.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/dp: Change AUX DPCD probe address from LANE0_1_STATUS to TRAINING_PATTERN_SET 2025-07-15T13:37:57+00:00 Imre Deak imre.deak@intel.com 2025-07-08T21:23:31+00:00 d34d6feaf4a76833effcec0b148b65946b04cde8 Commit a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") stopped using the DPCD_REV register for DPCD probing, since this results in link training failures at least when using an Intel Barlow Ridge TBT hub at UHBR link rates (the DP_INTRA_HOP_AUX_REPLY_INDICATION never getting cleared after the failed link training). Since accessing DPCD_REV during link training is prohibited by the DP Standard, LANE0_1_STATUS (0x202) was used instead, as it falls within the Standard's valid register address range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) and it fixed the link training on the above TBT hub. However, reading the LANE0_1_STATUS register also has a side-effect at least on a Novatek eDP panel, as reported on the Closes: link below, resulting in screen flickering on that panel. One clear side-effect when doing the 1-byte probe reads from LANE0_1_STATUS during link training before reading out the full 6 byte link status starting at the same address is that the panel will report the link training as completed with voltage swing 0. This is different from the normal, flicker-free scenario when no DPCD probing is done, the panel reporting the link training complete with voltage swing 2. Using the TRAINING_PATTERN_SET register for DPCD probing doesn't have the above side-effect, the panel will link train with voltage swing 2 as expected and it will stay flicker-free. This register is also in the above valid register range and is unlikely to have a side-effect as that of LANE0_1_STATUS: Reading LANE0_1_STATUS is part of the link training CR/EQ sequences and so it may cause a state change in the sink - even if inadvertently as I suspect in the case of the above Novatek panel. As opposed to this, reading TRAINING_PATTERN_SET is not part of the link training sequence (it must be only written once at the beginning of the CR/EQ sequences), so it's unlikely to cause any state change in the sink. As a side-note, this Novatek panel also lacks support for TPS3, while claiming support for HBR2, which violates the DP Standard (the Standard mandating TPS3 for HBR2). Besides the Novatek panel (PSR 1), which this change fixes, I also verified the change on a Samsung (PSR 1) and an Analogix (PSR 2) eDP panel as well as on the Intel Barlow Ridge TBT hub. Note that in the drm-tip tree (targeting the v6.17 kernel version) the i915 and xe drivers keep DPCD probing enabled only for the panel known to require this (HP ZR24w), hence those drivers in drm-tip are not affected by the above problem. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Fixes: a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") Reported-and-tested-by: Paul Menzel <pmenzel@molgen.mpg.de> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558 Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://lore.kernel.org/r/20250708212331.112898-1-imre.deak@intel.com (cherry picked from commit bba9aa41654036534d86b198f5647a9ce15ebd7f) [Imre: Rebased on drm-intel-fixes] Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> [Rodrigo: Changed original commit hash to match with the one propagated in fixes] 
Commit a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from
DPCD_REV to LANE0_1_STATUS") stopped using the DPCD_REV register for
DPCD probing, since this results in link training failures at least when
using an Intel Barlow Ridge TBT hub at UHBR link rates (the
DP_INTRA_HOP_AUX_REPLY_INDICATION never getting cleared after the failed
link training). Since accessing DPCD_REV during link training is
prohibited by the DP Standard, LANE0_1_STATUS (0x202) was used instead,
as it falls within the Standard's valid register address range
(0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) and it fixed the link
training on the above TBT hub.

However, reading the LANE0_1_STATUS register also has a side-effect at
least on a Novatek eDP panel, as reported on the Closes: link below,
resulting in screen flickering on that panel. One clear side-effect when
doing the 1-byte probe reads from LANE0_1_STATUS during link training
before reading out the full 6 byte link status starting at the same
address is that the panel will report the link training as completed
with voltage swing 0. This is different from the normal, flicker-free
scenario when no DPCD probing is done, the panel reporting the link
training complete with voltage swing 2.

Using the TRAINING_PATTERN_SET register for DPCD probing doesn't have
the above side-effect, the panel will link train with voltage swing 2 as
expected and it will stay flicker-free. This register is also in the
above valid register range and is unlikely to have a side-effect as that
of LANE0_1_STATUS: Reading LANE0_1_STATUS is part of the link training
CR/EQ sequences and so it may cause a state change in the sink - even if
inadvertently as I suspect in the case of the above Novatek panel. As
opposed to this, reading TRAINING_PATTERN_SET is not part of the link
training sequence (it must be only written once at the beginning of the
CR/EQ sequences), so it's unlikely to cause any state change in the
sink.

As a side-note, this Novatek panel also lacks support for TPS3, while
claiming support for HBR2, which violates the DP Standard (the Standard
mandating TPS3 for HBR2).

Besides the Novatek panel (PSR 1), which this change fixes, I also
verified the change on a Samsung (PSR 1) and an Analogix (PSR 2) eDP
panel as well as on the Intel Barlow Ridge TBT hub.

Note that in the drm-tip tree (targeting the v6.17 kernel version) the
i915 and xe drivers keep DPCD probing enabled only for the panel known
to require this (HP ZR24w), hence those drivers in drm-tip are not
affected by the above problem.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Fixes: a3ef3c2da675 ("drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS")
Reported-and-tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250708212331.112898-1-imre.deak@intel.com
(cherry picked from commit bba9aa41654036534d86b198f5647a9ce15ebd7f)
[Imre: Rebased on drm-intel-fixes]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[Rodrigo: Changed original commit hash to match with the one propagated in fixes]
Merge tag 'drm-misc-fixes-2025-06-26' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes 2025-06-27T20:53:00+00:00 Dave Airlie airlied@redhat.com 2025-06-27T20:53:00+00:00 9fbceb37c95939182e1409211447a1d3f3db9274 drm-misc-fixes for v6.16-rc4: - Fix function signature of drm_writeback_connector_cleanup. - Use correct HDMI audio bridge in drm_connector_hdmi_audio_init. - Make HPD work on SN65DSI86. Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://lore.kernel.org/r/3dd1d5e1-73b6-4b0c-a208-f7d6235cf530@linux.intel.com 
drm-misc-fixes for v6.16-rc4:
- Fix function signature of drm_writeback_connector_cleanup.
- Use correct HDMI audio bridge in drm_connector_hdmi_audio_init.
- Make HPD work on SN65DSI86.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://lore.kernel.org/r/3dd1d5e1-73b6-4b0c-a208-f7d6235cf530@linux.intel.com
drm/bridge-connector: Fix bridge in drm_connector_hdmi_audio_init() 2025-06-23T22:17:21+00:00 Chaoyi Chen chaoyi.chen@rock-chips.com 2025-06-20T01:16:16+00:00 10357824151262636fda879845f8b64553541106 The bridge used in drm_connector_hdmi_audio_init() does not correctly point to the required audio bridge, which lead to incorrect audio configuration input. Fixes: 231adeda9f67 ("drm/bridge-connector: hook DisplayPort audio support") Signed-off-by: Chaoyi Chen <chaoyi.chen@rock-chips.com> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Tested-by: Stephan Gerhold <stephan.gerhold@linaro.org> Link: https://lore.kernel.org/r/20250620011616.118-1-kernel@airkyi.com Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> 
The bridge used in drm_connector_hdmi_audio_init() does not correctly
point to the required audio bridge, which lead to incorrect audio
configuration input.

Fixes: 231adeda9f67 ("drm/bridge-connector: hook DisplayPort audio support")
Signed-off-by: Chaoyi Chen <chaoyi.chen@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Link: https://lore.kernel.org/r/20250620011616.118-1-kernel@airkyi.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS 2025-06-23T12:53:42+00:00 Imre Deak imre.deak@intel.com 2025-06-05T08:28:46+00:00 a3ef3c2da675a8a564c8bea1a511cdd0a2a9aa49 Reading DPCD registers has side-effects in general. In particular accessing registers outside of the link training register range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly forbidden by the DP v2.1 Standard, see 3.6.5.1 DPTX AUX Transaction Handling Mandates 3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates Based on my tests, accessing the DPCD_REV register during the link training of an UHBR TBT DP tunnel sink leads to link training failures. Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the DPCD register access quirk. Cc: <stable@vger.kernel.org> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com (cherry picked from commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> 
Reading DPCD registers has side-effects in general. In particular
accessing registers outside of the link training register range
(0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly
forbidden by the DP v2.1 Standard, see

3.6.5.1 DPTX AUX Transaction Handling Mandates
3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates

Based on my tests, accessing the DPCD_REV register during the link
training of an UHBR TBT DP tunnel sink leads to link training failures.

Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the
DPCD register access quirk.

Cc: <stable@vger.kernel.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com
(cherry picked from commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
drm/connector: only call HDMI audio helper plugged cb if non-null 2025-05-27T20:08:21+00:00 Nicolas Frattaroli nicolas.frattaroli@collabora.com 2025-05-27T17:57:08+00:00 be9b3f9a54101c19226c25ba7163d291183777a0 On driver remove, sound/soc/codecs/hdmi-codec.c calls the plugged_cb with NULL as the callback function and codec_dev, as seen in its hdmi_remove function. The HDMI audio helper then happily tries calling said null function pointer, and produces an Oops as a result. Fix this by only executing the callback if fn is non-null. This means the .plugged_cb and .plugged_cb_dev members still get appropriately cleared. Fixes: baf616647fe6 ("drm/connector: implement generic HDMI audio helpers") Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Link: https://lore.kernel.org/r/20250527-hdmi-audio-helper-remove-fix-v1-1-6cf77de364d8@collabora.com Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> 
On driver remove, sound/soc/codecs/hdmi-codec.c calls the plugged_cb
with NULL as the callback function and codec_dev, as seen in its
hdmi_remove function.

The HDMI audio helper then happily tries calling said null function
pointer, and produces an Oops as a result.

Fix this by only executing the callback if fn is non-null. This means
the .plugged_cb and .plugged_cb_dev members still get appropriately
cleared.

Fixes: baf616647fe6 ("drm/connector: implement generic HDMI audio helpers")
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250527-hdmi-audio-helper-remove-fix-v1-1-6cf77de364d8@collabora.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>