<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [BAT SKL]igt@kms_pipe_crc_basic@suspend-read-crc-pipe-c fails suspend autoresume" href="https://bugs.freedesktop.org/show_bug.cgi?id=94566#c13">Comment # 13</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [BAT SKL]igt@kms_pipe_crc_basic@suspend-read-crc-pipe-c fails suspend autoresume" href="https://bugs.freedesktop.org/show_bug.cgi?id=94566">bug 94566</a> from <a class="email" href="mailto:imre.deak@intel.com" title="Imre Deak <imre.deak@intel.com>"> Imre Deak</a> <pre>(In reply to Takashi Iwai from <a href="show_bug.cgi?id=94566#c12">comment #12</a>) > Aha, that's interesting. Now it gets clearer. > > My wild guess is like below: > > - The system boots with both i915 and HDA as modules, and they are loaded / > initialized asynchronously. > > - i915 init takes some time, while HD-audio starts initializing the bus at > first. > This results in the failure of the i915 component binding: > > [ 6.708025] snd_hda_intel 0000:00:1f.3: failed to add i915 component > master (-19) > > - Then i915 gets initialized, and HD-audio bus loads the HDMI codec driver. > The recent HDMI codec driver tries to bind with i915 by itself. It was > for the old chipset without Powerwell. At this time, the binding succeeds: > > [ 8.857780] snd_hda_intel 0000:00:1f.3: bound 0000:00:02.0 (ops > i915_audio_component_bind_ops [i915]) > > - Then the whole probe procedure finishes, it decreases the refcount, as if > the bus had also bound with i915. So it gets unbalanced. > > > So, for the unbalanced PM refcount itself, we can avoid it by disabling the > second on-demand binding. But it means nothing but the i915 / HDA binding > fails totally. There is no guarantee which module gets loaded first and so no guarantee that you won't get the "failed to add i915 component master (-19)" error. The only proper way to solve this is to initialize anything needing the display driver from the component bind hook (hdac_component_master_bind).</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>