PM: runtime: Add kunit test for supplier idle/suspend

Add a unit test that covers the bugfix/optimization in the previous
patch, "PM: runtime: Only queue an idle check for RPM-linked suppliers".

This test ensures:

1) device links with DL_FLAG_PM_RUNTIME can RPM-resume/suspend properly;
   and

2) device links without DL_FLAG_PM_RUNTIME are not accidentally
   resumed/suspended along with the consumer.

Notably, without patch 1 ("PM: runtime: Only queue an idle check for
RPM-linked suppliers"), the no-RPM supplier will fail 2 of its last 3
test expectations:

  $ tools/testing/kunit/kunit.py run --kconfig_add CONFIG_PM=y 'pm_runtime*'

  ...

  ## Fails because rpm_suspend_suppliers() suspended the wrong links
  [17:01:44] # pm_runtime_supplier_suspend_test: EXPECTATION FAILED at drivers/base/power/runtime-test.c:279
  [17:01:44] Expected pm_runtime_active(norpm_supplier) to be true, but is false

  ## Fails because the no-RPM supplier is already suspended unexpectedly
  [17:01:44] # pm_runtime_supplier_suspend_test: EXPECTATION FAILED at drivers/base/power/runtime-test.c:282
  [17:01:44] Expected 0 == pm_runtime_suspend(norpm_supplier), but
  [17:01:44]     pm_runtime_suspend(norpm_supplier) == 1 (0x1)
  ...

Signed-off-by: Brian Norris <briannorris@chromium.org>
Link: https://patch.msgid.link/20260901013341.1417232-2-briannorris@chromium.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

0 files changed, 0 insertions, 0 deletions