Fix SDVO HDMI encoding detect (#16920)

Check return value of get supported encode command and current
encoding mode, which could be DVI or HDMI.
(cherry picked from commit f91134795b545c8baebf218975b261c76a0e5873)

1 files changed, 26 insertions, 4 deletions

diff --git a/src/i830_sdvo.c b/src/i830_sdvo.c
index 701aeaa1..8f1b20b7 100644
--- a/src/i830_sdvo.c
+++ b/src/i830_sdvo.c
@@ -79,6 +79,11 @@ struct i830_sdvo_priv {
     Bool is_tv;
 
     /**
+     * This is set if we treat the device as HDMI, instead of DVI.
+     */
+    Bool is_hdmi;
+
+    /**
      * Returned SDTV resolutions allowed for the current format, if the
      * device reported it.
      */
@@ -770,7 +775,7 @@ i830_sdvo_get_supp_encode(xf86OutputPtr output, struct i830_sdvo_encode *encode)
 
     i830_sdvo_write_cmd(output, SDVO_CMD_GET_SUPP_ENCODE, NULL, 0);
     status = i830_sdvo_read_response(output, encode, sizeof(*encode));
-    if (status != SDVO_CMD_STATUS_SUCCESS) {
+    if (status != SDVO_CMD_STATUS_SUCCESS) { /* non-support means DVI */
 	memset(encode, 0, sizeof(*encode));
 	return FALSE;
     }
@@ -1034,7 +1039,7 @@ i830_sdvo_mode_set(xf86OutputPtr output, DisplayModePtr mode,
 			&in_out, sizeof(in_out));
     status = i830_sdvo_read_response(output, NULL, 0);
 
-    if (dev_priv->encode.hdmi_rev)
+    if (dev_priv->is_hdmi)
 	i830_sdvo_set_avi_infoframe(output, mode);
 
     i830_sdvo_get_dtd_from_mode(&input_dtd, mode);
@@ -1722,6 +1727,22 @@ i830_sdvo_select_ddc_bus(struct i830_sdvo_priv *dev_priv)
     dev_priv->ddc_bus = 1 << num_bits;
 }
 
+static Bool
+i830_sdvo_get_digital_encoding_mode(xf86OutputPtr output)
+{
+    I830OutputPrivatePtr    intel_output = output->driver_private;
+    struct i830_sdvo_priv   *dev_priv = intel_output->dev_priv;
+    uint8_t status;
+
+    i830_sdvo_set_target_output(output, dev_priv->controlled_output);
+
+    i830_sdvo_write_cmd(output, SDVO_CMD_GET_ENCODE, NULL, 0);
+    status = i830_sdvo_read_response(output, &dev_priv->is_hdmi, 1);
+    if (status != SDVO_CMD_STATUS_SUCCESS)
+	return FALSE;
+    return TRUE;
+}
+
 Bool
 i830_sdvo_init(ScrnInfoPtr pScrn, int output_device)
 {
@@ -1849,8 +1870,9 @@ i830_sdvo_init(ScrnInfoPtr pScrn, int output_device)
         output->subpixel_order = SubPixelHorizontalRGB;
 	name_prefix="TMDS";
 
-	i830_sdvo_get_supp_encode(output, &dev_priv->encode);
-	if (dev_priv->encode.hdmi_rev != 0) {
+	if (i830_sdvo_get_supp_encode(output, &dev_priv->encode) &&
+		i830_sdvo_get_digital_encoding_mode(output) &&
+		dev_priv->is_hdmi) {
 	    /* enable hdmi encoding mode if supported */
 	    i830_sdvo_set_encode(output, SDVO_ENCODE_HDMI);
 	    i830_sdvo_set_colorimetry(output, SDVO_COLORIMETRY_RGB256);