<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - DP audio not work on KBL(regression issue)" href="https://bugs.freedesktop.org/show_bug.cgi?id=104093#c1">Comment # 1</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - DP audio not work on KBL(regression issue)" href="https://bugs.freedesktop.org/show_bug.cgi?id=104093">bug 104093</a> from <a class="email" href="mailto:alice.liu@intel.com" title="Alice Liu <alice.liu@intel.com>"> Alice Liu</a> <pre>Here is the regression commit. commit 6014ac122ed081feca99217bc57b2e15c7fc1a51 Author: Libin Yang <<a href="mailto:libin.yang@linux.intel.com">libin.yang@linux.intel.com</a>> Date: Tue Oct 25 17:54:18 2016 +0300 drm/i915/audio: set proper N/M in modeset When modeset occurs and the LS_CLK is set to some special values in DP mode, the N/M need to be set manually if audio is playing. Otherwise the first several seconds may be silent in audio playback. The relationship of Maud and Naud is expressed in the following equation: Maud/Naud = 512 * fs / f_LS_Clk Please refer VESA DisplayPort Standard spec for details. v2 by Jani: - organize Maud/Naud table according to DP 1.4 spec - add 64k and 128k audio rates - update HSW_AUD_M_CTS_ENABLE register when Maud not found - remove extra checks for port clock - simplify Maud/Naud lookup - reset patch author back to Libin Cc: "Zhang, Keqiao" <<a href="mailto:keqiao.zhang@intel.com">keqiao.zhang@intel.com</a>> Cc: Ville Syrjälä <<a href="mailto:ville.syrjala@linux.intel.com">ville.syrjala@linux.intel.com</a>> Cc: "Lin, Mengdong" <<a href="mailto:mengdong.lin@intel.com">mengdong.lin@intel.com</a>> Reviewed-by: Ville Syrjälä <<a href="mailto:ville.syrjala@linux.intel.com">ville.syrjala@linux.intel.com</a>> Signed-off-by: Libin Yang <<a href="mailto:libin.yang@linux.intel.com">libin.yang@linux.intel.com</a>> Signed-off-by: Jani Nikula <<a href="mailto:jani.nikula@intel.com">jani.nikula@intel.com</a>> Link: <a href="http://patchwork.freedesktop.org/patch/msgid/1477407258-30599-3-git-send-email-jani.nikula@intel.com">http://patchwork.freedesktop.org/patch/msgid/1477407258-30599-3-git-send-email-jani.nikula@intel.com</a></pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> <li>You are on the CC list for the bug.</li> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>