[PATCH i-g-t v6 21/23] tests/core_hotunplug: HSW audio issue workaround

[Janusz Krzysztofik]

Unbinding the i915 driver on some Haswell platforms with Azalia audio
results in a kernel WARNING on "i915 raw-wakerefs=1 wakelocks=1 on
cleanup".  The issue can be worked around by manually enabling runtime
power management for the conflicting audio adapter.  Use that method
but also display a warning to preserve visibility of the issue.  Also
tag the workaround with a FIXME comment.

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik at linux.intel.com>
---
 tests/core_hotunplug.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
index 91b3caeda..292df98bc 100644
--- a/tests/core_hotunplug.c
+++ b/tests/core_hotunplug.c
@@ -482,9 +482,23 @@ igt_main
 		igt_skip_on_f(fd_drm < 0, "No known DRM device found\n");
 
 		if (is_i915_device(fd_drm)) {
+			uint32_t devid = intel_get_drm_devid(fd_drm);
+
 			gem_quiescent_gpu(fd_drm);
 			igt_skip_on_f(local_i915_healthcheck(fd_drm, "pre-"),
 				      "i915 device not healthy on test start\n");
+
+			/**
+			 * FIXME: Unbinding the i915 driver on some Haswell
+			 * platforms with Azalia audio results in a kernel WARN
+			 * on "i915 raw-wakerefs=1 wakelocks=1 on cleanup".  The
+			 * below CI friendly user level workaround prevents the
+			 * warning from appearing.  Drop this hack as soon as
+			 * this is fixed in the kernel.
+			 */
+			if (igt_warn_on_f((bool) IS_HASWELL(devid),
+			    "Manually enabling audio PM to work around a kernel WARN\n"))
+				igt_pm_enable_audio_runtime_pm();
 		}
 
 		/* Make sure subtests always reopen the same device */
-- 
2.21.1