<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#c18">Comment # 18</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#c16">comment #16</a>) > Well, this is a sort of chicken-and-egg problem. For probing the HDMI > codec, i915 binding is needed, yes. But, for knowing whether it's a HDMI > codec or not, we need to probe the codec at first. Thus the driver needs > the i915 binding *before* probing the codec. Yet, i915 binding can't be > done when the system has no i915 graphics... I don't think it's a chicken-and-egg problem. There are two possibilities: 1. Probing the codec needs a power well provided by the i915 device and as such the i915 driver. In this case there must be an i915 graphics device physically present in the system and so you can load the i915 driver which will end up doing the binding. You said that it's not clear yet whether this HW dependency really exists, I have no idea either, so someone needs to find the definite answer for this. 2. Probing the codec doesn't need an i915 provided power well (or any other functionality provided via the component interface), in which case there is no problem you just need to remove the power_well get/puts and probe the codec whenever. > We may look for Intel VGA PCI entries, and enable i915 binding only when > found. This would work in most cases, but not in 100%. User may still > build / use a system without graphics (e.g. booting with nomodeset option). In case 1. above booting with modeset or otherwise not having the i915 driver for some reason would also imply a lack of audio support, that is you would need to fail the probing of the audio driver.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are on the CC list for the bug.</li> <li>You are the assignee for the bug.</li> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>