[igt-dev] [i-g-t V5 6/9] tests/kms_vrr: Add a helper to get the low refresh mode

[Bhanuprakash Modem <bhanuprakash.modem@intel.com>]

To switch the refresh rate seamlessly, add a new helper to
identify the mode with the same resolution but low vrefresh
and clock.

Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem@intel.com>
---
 tests/kms_vrr.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/tests/kms_vrr.c b/tests/kms_vrr.c
index 422d89073..26f89f7a8 100644
--- a/tests/kms_vrr.c
+++ b/tests/kms_vrr.c
@@ -166,6 +166,24 @@ output_mode_with_maxrate(igt_output_t *output, unsigned int vrr_max)
 	return mode;
 }
 
+static drmModeModeInfo
+low_rr_mode_with_same_res(igt_output_t *output, unsigned int vrr_min)
+{
+	int i;
+	drmModeConnectorPtr connector = output->config.connector;
+	drmModeModeInfo mode = *igt_output_get_mode(output);
+
+	for (i = 0; i < connector->count_modes; i++)
+		if (connector->modes[i].hdisplay == mode.hdisplay &&
+		    connector->modes[i].vdisplay == mode.vdisplay &&
+		    connector->modes[i].clock < mode.clock &&
+		    connector->modes[i].vrefresh < mode.vrefresh &&
+		    connector->modes[i].vrefresh >= vrr_min)
+			mode = connector->modes[i];
+
+	return mode;
+}
+
 /* Read min and max vrr range from the connector debugfs. */
 static range_t
 get_vrr_range(data_t *data, igt_output_t *output)
-- 
2.40.0