[PATCH v3 1/2] tests/intel/kms_pm_dc: Add DC5 DPMS suspend/resume validation test

[Mohammed Thasleem <mohammed.thasleem@intel.com>]

Validate DC5 state entry before and after suspend/resume cycle using DPMS.
Ensures DC5 functionality is preserved across system suspend/resume
operations.

v2: Remove repeated word. (Pranay)
    Remove extra line.
v3: Update test description. (Jeevan)

Signed-off-by: Mohammed Thasleem <mohammed.thasleem@intel.com>
---
 tests/intel/kms_pm_dc.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/intel/kms_pm_dc.c b/tests/intel/kms_pm_dc.c
index 423a5c4a4..249d9e11a 100644
--- a/tests/intel/kms_pm_dc.c
+++ b/tests/intel/kms_pm_dc.c
@@ -77,6 +77,9 @@
  *
  * SUBTEST: dc5-retention-flops
  * Description: This test validates display engine entry to DC5 state while PSR is active on Pipe B
+ *
+ * SUBTEST: dc5-dpms-suspend-resume
+ * Description: This test validates DC5 state entry before and after a suspend/resume cycle using DPMS
  */
 
 #define PWR_DOMAIN_INFO "i915_power_domain_info"
@@ -622,6 +625,13 @@ static void test_deep_pkgc_state(data_t *data)
 	igt_assert_f(pkgc_flag, "PKGC10 is not achieved.\n");
 }
 
+static void test_dc5_dpms_suspend_resume(data_t *data, int dc_flag)
+{
+	test_dc_state_dpms(data, dc_flag);
+	igt_system_suspend_autoresume(SUSPEND_STATE_MEM, SUSPEND_TEST_NONE);
+	test_dc_state_dpms(data, dc_flag);
+}
+
 static void kms_poll_state_restore(int sig)
 {
 	int sysfs_fd;
@@ -743,6 +753,11 @@ int igt_main()
 		test_dc9_dpms(&data);
 	}
 
+	igt_describe("This test validates DC5 state entry before and after a "
+		      "suspend/resume cycle using DPMS");
+	igt_subtest("dc5-dpms-suspend-resume")
+		test_dc5_dpms_suspend_resume(&data, IGT_INTEL_CHECK_DC5);
+
 	igt_fixture() {
 		free(data.debugfs_dump);
 		close(data.debugfs_fd);
-- 
2.43.0