[PATCH v2 26/27] drm/debugfs: Expose HDMI VRR in vrr_range debugfs

[Nicolas Frattaroli]

IGT requires the vrr_range debugfs file for running the tests, for
better or worse.

Since Commit 014da1db5e64 ("drm/edid: parse HDMI 2.1 gaming (ALLM/VRR)
capabilities from HF-VSDB") parses the HDMI VRR minimum and maximum
numbers into separate members and not the display_info.monitor_range
member, this debugfs entry needs to use those members when the display
is HDMI and does HDMI VRR.

Add this special casing, and also protect accesses to connector->status
and connector->display_info interruptibly with the mode_config mutex.

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli at collabora.com>
---
 drivers/gpu/drm/drm_debugfs.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index a72f9723d3a9..476f44642ac3 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -586,12 +586,26 @@ static ssize_t edid_write(struct file *file, const char __user *ubuf,
 static int vrr_range_show(struct seq_file *m, void *data)
 {
 	struct drm_connector *connector = m->private;
+	u16 min_vfreq, max_vfreq;
+
+	scoped_cond_guard(mutex_intr, return -EINTR,
+			  &connector->dev->mode_config.mutex) {
+		struct drm_display_info *info = &connector->display_info;
+
+		if (connector->status != connector_status_connected)
+			return -ENODEV;
+
+		if (info->is_hdmi && info->hdmi.vrr_cap.supported) {
+			min_vfreq = info->hdmi.vrr_cap.vrr_min;
+			max_vfreq = info->hdmi.vrr_cap.vrr_max;
+		} else {
+			min_vfreq = info->monitor_range.min_vfreq;
+			max_vfreq = info->monitor_range.max_vfreq;
+		}
+	}
 
-	if (connector->status != connector_status_connected)
-		return -ENODEV;
-
-	seq_printf(m, "Min: %u\n", connector->display_info.monitor_range.min_vfreq);
-	seq_printf(m, "Max: %u\n", connector->display_info.monitor_range.max_vfreq);
+	seq_printf(m, "Min: %u\n", min_vfreq);
+	seq_printf(m, "Max: %u\n", max_vfreq);
 
 	return 0;
 }

-- 
2.56.0