drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS
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>
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