MLK-21553 drm/bridge: it6263: Do hotplug detect quickly in unforced case

We should avoid expensive, destructive operations during automated hotplug
probing, otherwise, it could cause flickering on other running displays.
So, let's check the parameter 'force' of ->detect() and do the appropriate
detection accordingly.

Reported-by: Luo Danwei <danwei.luo@nxp.com>
Tested-by: Luo Danwei <danwei.luo@nxp.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>

diff --git a/drivers/gpu/drm/bridge/it6263.c b/drivers/gpu/drm/bridge/it6263.c
index 3c314c4..4548c27 100644 (file)
--- a/drivers/gpu/drm/bridge/it6263.c
+++ b/drivers/gpu/drm/bridge/it6263.c
@@ -457,24 +457,36 @@ static void it6263_hdmi_config(struct it6263 *it6263)
                                                HDMI_COLOR_DEPTH_24);
 }
 
+static bool it6263_hpd_is_connected(struct it6263 *it6263)
+{
+       unsigned int status;
+
+       regmap_read(it6263->hdmi_regmap, HDMI_REG_SYS_STATUS, &status);
+
+       return !!(status & HPDETECT);
+}
+
 static enum drm_connector_status
 it6263_connector_detect(struct drm_connector *connector, bool force)
 {
        struct it6263 *it6263 = connector_to_it6263(connector);
-       unsigned int status;
        int i;
 
-       /*
-        * FIXME: We read status tens of times to workaround
-        * cable detection failure issue at boot time on some
-        * platforms.
-        * Spin on this for up to one second.
-        */
-       for (i = 0; i < 100; i++) {
-               regmap_read(it6263->hdmi_regmap, HDMI_REG_SYS_STATUS, &status);
-               if (status & HPDETECT)
+       if (force) {
+               /*
+                * FIXME: We read status tens of times to workaround
+                * cable detection failure issue at boot time on some
+                * platforms.
+                * Spin on this for up to one second.
+                */
+               for (i = 0; i < 100; i++) {
+                       if (it6263_hpd_is_connected(it6263))
+                               return connector_status_connected;
+                       usleep_range(5000, 10000);
+               }
+       } else {
+               if (it6263_hpd_is_connected(it6263))
                        return connector_status_connected;
-               usleep_range(5000, 10000);
        }
 
        return connector_status_disconnected;