mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 09:50:04 +00:00
No description
4361ccac28
Atm AUX-B transfers can fail with the following error if AUX-A is not enabled: [ 594.594108] [drm:intel_dp_aux_xfer [i915]] dp_aux_ch timeout status 0x7c2003ff [ 594.615854] [drm:intel_dp_aux_xfer [i915]] *ERROR* dp aux hw did not signal timeout! [ 594.632851] [drm:intel_dp_aux_xfer [i915]] *ERROR* dp aux hw did not signal timeout! [ 594.632915] [drm:intel_dp_aux_xfer [i915]] *ERROR* dp_aux_ch not done status 0xac2003ff [ 594.641786] ------------[ cut here ]------------ [ 594.641790] dp_aux_ch not started status 0xac2003ff [ 594.641874] WARNING: CPU: 4 PID: 1366 at drivers/gpu/drm/i915/intel_dp.c:1268 intel_dp_aux_xfer+0x232/0x890 [i915] Ville noticed this issue already earlier and managed to work around it by keeping AUX-A always powered whenever AUX-B was used. He also reported the issue to HW folks and they have now root caused the problem and updated BSpec with a fix (see internal BSpec/Index/21257, HSD/1607152412). I noticed the same error - even with the WA being applied - while doing AUX transfers with Chamelium being connected with a DP cable to the source but letting Chamelium imitate an unplug. This is probably some unstandard way on Chamelium's behalf of disconnecting itself from the AUX pins. For instance it could still pull on the AUX pins which would prevent the source from detecting AUX timeouts in the proper way, leading to the ERRORs or WARNs seen in the logs in the Reference: bug below. In case I disconnect the sink properly (the cable itself, not via the Chamelium unplug xmlrpc command) then the AUX timeout signaling works properly and so there won't be any ERRORs/WARNs emitted. Reference: https://bugs.freedesktop.org/show_bug.cgi?id=110718 Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190524173532.6444-1-imre.deak@intel.com |
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.