kernel/linux.git/drivers/gpu/drm/display, branch linux-6.0.y

drm/display/dp_mst: Fix drm_dp_mst_add_affected_dsc_crtcs() return code

2022-12-02T16:43:17+00:00

commit 2f3a1273862cb82cca227630cc7f04ce0c94b6bb upstream. Looks like that we're accidentally dropping a pretty important return code here. For some reason, we just return -EINVAL if we fail to get the MST topology state. This is wrong: error codes are important and should never be squashed without being handled, which here seems to have the potential to cause a deadlock. Signed-off-by: Lyude Paul Reviewed-by: Wayne Lin Fixes: 8ec046716ca8 ("drm/dp_mst: Add helper to trigger modeset on affected DSC MST CRTCs") Cc: # v5.6+ Signed-off-by: Alex Deucher Signed-off-by: Greg Kroah-Hartman

drm/display: Don't assume dual mode adaptors support i2c sub-addressing

2022-11-26T08:27:42+00:00

commit 5954acbacbd1946b96ce8ee799d309cb0cd3cb9d upstream. Current dual mode adaptor ("DP++") detection code assumes that all adaptors support i2c sub-addressing for read operations from the DP-HDMI adaptor ID buffer. It has been observed that multiple adaptors do not in fact support this, and always return data starting at register 0. On affected adaptors, the code fails to read the proper registers that would identify the device as a type 2 adaptor, and handles those as type 1, limiting the TMDS clock to 165MHz, even if the according register would announce a higher TMDS clock. Fix this by always reading the ID buffer starting from offset 0, and discarding any bytes before the actual offset of interest. We tried finding authoritative documentation on whether or not this is allowed behaviour, but since all the official VESA docs are paywalled, the best we could come up with was the spec sheet for Texas Instruments' SNx5DP149 chip family.[1] It explicitly mentions that sub-addressing is supported for register writes, but *not* for reads (See NOTE in section 8.5.3). Unless TI openly decided to violate the VESA spec, one could take that as a hint that sub-addressing is in fact not mandated by VESA. The other two adaptors affected used the PS8409(A) and the LT8611, according to the data returned from their ID buffers. [1] https://www.ti.com/lit/ds/symlink/sn75dp149.pdf Cc: stable@vger.kernel.org Signed-off-by: Simon Rettberg Reviewed-by: Rafael Gieschke Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20221006113314.41101987@computer Acked-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman

drm/dp: Don't rewrite link config when setting phy test pattern

2022-10-21T10:39:17+00:00

[ Upstream commit 7b4d8db657192066bc6f1f6635d348413dac1e18 ] The sequence for Source DP PHY CTS automation is [2][1]: 1- Emulate successful Link Training(LT) 2- Short HPD and change link rates and number of lanes by LT. (This is same flow for Link Layer CTS) 3- Short HPD and change PHY test pattern and swing/pre-emphasis levels (This step should not trigger LT) The problem is with DP PHY compliance setup as follow: [DPTX + on board LTTPR]------Main Link--->[Scope] ^ | | | | | ----------Aux Ch------>[Aux Emulator] At step 3, before writing TRAINING_LANEx_SET/LINK_QUAL_PATTERN_SET to declare the pattern/swing requested by scope, we write link config in LINK_BW_SET/LANE_COUNT_SET on a port that has LTTPR. As LTTPR snoops aux transaction, LINK_BW_SET/LANE_COUNT_SET writes indicate a LT will start [Check DP 2.0 E11 -Sec 3.6.8.2 & 3.6.8.6.3], and LTTPR will reset the link and stop sending DP signals to DPTX/Scope causing the measurements to fail. Note that step 3 will not trigger LT and DP link will never recovered by the Aux Emulator/Scope. The reset of link can be tested with a monitor connected to LTTPR port simply by writing to LINK_BW_SET or LANE_COUNT_SET as follow igt/tools/dpcd_reg write --offset=0x100 --value 0x14 --device=2 OR printf '\x14' | sudo dd of=/dev/drm_dp_aux2 bs=1 count=1 conv=notrunc seek=$((0x100)) This single aux write causes the screen to blank, sending short HPD to DPTX, setting LINK_STATUS_UPDATE = 1 in DPCD 0x204, and triggering LT. As stated in [1]: "Before any TX electrical testing can be performed, the link between a DPTX and DPRX (in this case, a piece of test equipment), including all LTTPRs within the path, shall be trained as defined in this Standard." In addition, changing Phy pattern/Swing/Pre-emphasis (Step 3) uses the same link rate and lane count applied on step 2, so no need to redo LT. The fix is to not rewrite link config in step 3, and just writes TRAINING_LANEx_SET and LINK_QUAL_PATTERN_SET [1]: DP 2.0 E11 - 3.6.11.1 LTTPR DPTX_PHY Electrical Compliance [2]: Configuring UnigrafDPTC Controller - Automation Test Sequence https://www.keysight.com/us/en/assets/9922-01244/help-files/ D9040DPPC-DisplayPort-Test-Software-Online-Help-latest.chm Cc: Imre Deak Cc: Jani Nikula Cc: Or Cochvi Signed-off-by: Khaled Almahallawy Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20220916054900.415804-1-khaled.almahallawy@intel.com Signed-off-by: Sasha Levin

drm/dp_mst: fix drm_dp_dpcd_read return value checks

2022-10-21T10:38:23+00:00

[ Upstream commit 2ac6cdd581f48c8f68747156fde5868486a44985 ] drm_dp_dpcd_read returns the number of bytes read. The previous code would print garbage on DPCD error, and would exit with on error on success. Signed-off-by: Simon Ser Fixes: cb897542c6d2 ("drm/dp_mst: Fix W=1 warnings") Cc: Lyude Paul Cc: Benjamin Gaignard Reviewed-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/473500/ Signed-off-by: Sasha Levin

drm: Remove linux/fb.h from drm_crtc.h

2022-07-05T18:14:02+00:00

drm_crtc.h has no need for linux/fb.h, so don't include it. Avoids useless rebuilds of the entire universe when touching linux/fb.h. Quite a few placs do currently depend on linux/fb.h or other headers pulled in by it without actually including any of it directly. All of those need to be fixed up. v2: Split the vmwgfx change out Acked-by: Sam Ravnborg Acked-by: Jani Nikula Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220630195114.17407-3-ville.syrjala@linux.intel.com

drm/display: Fix build error without CONFIG_OF

2022-06-23T14:18:02+00:00

While CONFIG_OF is n but COMPILE_TEST is y, we got this: WARNING: unmet direct dependencies detected for DRM_DP_AUX_BUS Depends on [n]: HAS_IOMEM [=y] && DRM [=y] && OF [=n] Selected by [y]: - DRM_MSM [=y] && HAS_IOMEM [=y] && DRM [=y] && (ARCH_QCOM || SOC_IMX5 || COMPILE_TEST [=y]) && COMMON_CLK [=y] && IOMMU_SUPPORT [=y] && (QCOM_OCMEM [=n] || QCOM_OCMEM [=n]=n) && (QCOM_LLCC [=y] || QCOM_LLCC [=y]=n) && (QCOM_COMMAND_DB [=n] || QCOM_COMMAND_DB [=n]=n) Make DRM_DP_AUX_BUS depends on OF || COMPILE_TEST to fix this warning. Fixes: 1e0f66420b13 ("drm/display: Introduce a DRM display-helper module") Signed-off-by: YueHaibing Reviewed-by: Dmitry Baryshkov Reviewed-by: Abhinav Kumar Acked-by: Linus Walleij Signed-off-by: Linus Walleij Link: https://patchwork.freedesktop.org/patch/msgid/20220611041612.1976-1-yuehaibing@huawei.com

drm/dp_mst: Get rid of old comment in drm_atomic_get_mst_topology_state docs

2022-06-21T19:38:51+00:00

We don't actually care about connection_mutex here anymore, so let's get rid of the comment mentioning it in this function's kdocs. Signed-off-by: Lyude Paul Reviewed-by: Wayne Lin Link: https://patchwork.freedesktop.org/patch/msgid/20220602201757.30431-4-lyude@redhat.com

drm/display/dp_mst: Don't validate port refs in drm_dp_check_and_send_link_address()

2022-06-21T19:38:36+00:00

Drive-by cleanup, we don't need to validate the port references here as we already previously went through the effort of refactoring things such that we're guaranteed to be able to access ->mstb and ->port safely from drm_dp_check_and_send_link_address(), since the only two places in the codebase that drop an MST reference in such a way that it would remove it from the topology are both protected under probe_lock. Thanks for that, past Lyude! Signed-off-by: Lyude Paul Reviewed-by: Wayne Lin Link: https://patchwork.freedesktop.org/patch/msgid/20220602201757.30431-2-lyude@redhat.com

drm/display: Remove duplicate 'the' in two places.

2022-06-21T19:29:45+00:00

there is an unexpected word "the" in the comments that need to be dropped file: drivers/gpu/drm/display/drm_dp_helper.c line: 1600 * Doesn't account the the "MOT" bit, and instead assumes each changed to * Doesn't account the "MOT" bit, and instead assumes eac Signed-off-by: Jiang Jian Signed-off-by: Lyude Paul Link: https://patchwork.freedesktop.org/patch/msgid/20220621190055.8323-1-jiangjian@cdjrlc.com

drm: Drop drm_edid.h from drm_crtc.h

2022-06-20T20:53:55+00:00

drm_crtc.h has no need for drm_edid.h, so don't include it. Avoids useless rebuilds of the entire universe when touching drm_edid.h. Quite a few placs do currently depend on drm_edid.h without actually including it directly. All of those need to be fixed up. v2: Fix up i915 and msm some more v3: Fix alphabetical ordering (Sam) Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220614090245.30283-1-ville.syrjala@linux.intel.com Acked-by: Sam Ravnborg Acked-by: Jani Nikula