[igt-dev] [PATCH i-g-t] [intel-gfx] tests/pm_backlight.c : Brightness test with DPMS and System suspend.

[Yadav Jyoti]

From: Jyoti Yadav <jyoti.r.yadav at intel.com>

    BIOS programs few of PWM related registers during initial boot.
    But during System suspend those registers are cleared.
    This test aims to check whether display programs those registers properly after
    system resume.
    Also checks brightness programming during DPMS ON/OFF cycle to check backlight
    programming is done properly from display side.

    Signed-off-by: Jyoti Yadav <jyoti.r.yadav at intel.com>
---
 tests/pm_backlight.c | 99 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 98 insertions(+), 1 deletion(-)

diff --git a/tests/pm_backlight.c b/tests/pm_backlight.c
index bc1d417..72e23ea 100644
--- a/tests/pm_backlight.c
+++ b/tests/pm_backlight.c
@@ -90,6 +90,51 @@ static int backlight_write(int value, const char *fname)
 
 	return 0;
 }
+/* If we want to actually reach PC8+ states, we need to properly configure all
+ * the devices on the system to allow this. This function will try to setup the
+ * things we know we need, but won't scream in case anything fails: we don't
+ * know which devices are present on your machine, so we can't really expect
+ * anything, just try to help with the more common problems. */
+static void setup_non_graphics_runtime_pm(void)
+{
+	int fd, i;
+	char *file_name;
+
+	/* Disk runtime PM policies. */
+	file_name = malloc(PATH_MAX);
+	for (i = 0; ; i++) {
+
+		snprintf(file_name, PATH_MAX,
+			 "/sys/class/scsi_host/host%d/link_power_management_policy",
+			 i);
+
+		fd = open(file_name, O_WRONLY);
+		if (fd < 0)
+			break;
+
+		igt_assert(write(fd, "min_power\n", 10) == 10);
+		close(fd);
+	}
+	free(file_name);
+}
+static void disable_all_screens_dpms(int drm_fd, drmModeResPtr res_ptr)
+{
+	int i;
+	for (i = 0; i < res_ptr->count_connectors; i++) {
+		drmModeConnectorPtr c = drmModeGetConnector(drm_fd,
+						res_ptr->connectors[i]);
+		kmstest_set_connector_dpms(drm_fd, c, DRM_MODE_DPMS_OFF);
+	}
+}
+static void enable_all_screens_dpms(int drm_fd, drmModeResPtr res_ptr)
+{
+	int i;
+	for (i = 0; i < res_ptr->count_connectors; i++) {
+		drmModeConnectorPtr c = drmModeGetConnector(drm_fd,
+						res_ptr->connectors[i]);
+		kmstest_set_connector_dpms(drm_fd, c, DRM_MODE_DPMS_ON);
+	}
+}
 
 static void test_and_verify(int val)
 {
@@ -145,9 +190,52 @@ static void test_fade(int max)
 	}
 }
 
+
+static void test_fade_with_dpms(int max , int drm_fd, drmModeResPtr res_ptr)
+{
+	int i;
+	static const struct timespec ts = { .tv_sec = 0, .tv_nsec = FADESPEED*1000000 };
+	bool has_runtime_pm;
+	has_runtime_pm = igt_setup_runtime_pm();
+	igt_info("Runtime PM support: %d\n", has_runtime_pm);
+	igt_assert(has_runtime_pm);
+	disable_all_screens_dpms(drm_fd, res_ptr);
+	igt_assert(igt_wait_for_pm_status(IGT_RUNTIME_PM_STATUS_SUSPENDED));
+	enable_all_screens_dpms(drm_fd, res_ptr);
+	igt_assert(igt_wait_for_pm_status(IGT_RUNTIME_PM_STATUS_ACTIVE));
+	/* Fade out, then in */
+	for (i = max; i > 0; i -= max / FADESTEPS) {
+		test_and_verify(i);
+		nanosleep(&ts, NULL);
+	}
+	for (i = 0; i <= max; i += max / FADESTEPS) {
+		test_and_verify(i);
+		nanosleep(&ts, NULL);
+	}
+}
+static void test_fade_with_suspend(int max, int drm_fd, drmModeResPtr res_ptr )
+{
+	int i;
+	static const struct timespec ts = { .tv_sec = 0, .tv_nsec = FADESPEED*1000000 };
+	disable_all_screens_dpms(drm_fd, res_ptr);
+	igt_system_suspend_autoresume();
+	igt_assert(igt_wait_for_pm_status(IGT_RUNTIME_PM_STATUS_SUSPENDED));
+
+	/* Fade out, then in */
+	for (i = max; i > 0; i -= max / FADESTEPS) {
+		test_and_verify(i);
+		nanosleep(&ts, NULL);
+	}
+	for (i = 0; i <= max; i += max / FADESTEPS) {
+		test_and_verify(i);
+		nanosleep(&ts, NULL);
+	}
+}
+
 igt_main
 {
-	int max, old;
+	int drm_fd, max, old;
+	drmModeResPtr res;
 
 	igt_skip_on_simulation();
 
@@ -155,6 +243,10 @@ igt_main
 		/* Get the max value and skip the whole test if sysfs interface not available */
 		igt_skip_on(backlight_read(&old, "brightness"));
 		igt_assert(backlight_read(&max, "max_brightness") > -1);
+		drm_fd = drm_open_any_master();
+		res = drmModeGetResources(drm_fd);
+		igt_assert(res);
+		setup_non_graphics_runtime_pm();
 	}
 
 	igt_subtest("basic-brightness")
@@ -163,9 +255,14 @@ igt_main
 		test_bad_brightness(max);
 	igt_subtest("fade")
 		test_fade(max);
+	igt_subtest("fade-with-dpms")
+		test_fade_with_dpms(max, drm_fd, res);
+	igt_subtest("fade-with-suspend")
+		test_fade_with_suspend(max, drm_fd, res);
 
 	igt_fixture {
 		/* Restore old brightness */
 		backlight_write(old, "brightness");
+		drmClose(drm_fd);
 	}
 }
-- 
1.9.1