@@ -522,19 +522,32 @@ static bool intel_sdvo_read_response(struct intel_sdvo *intel_sdvo,
* command to be complete.
*
* Check 5 times in case the hardware failed to read the docs.
+ *
+ * Also beware that the first response by many devices is to
+ * reply PENDING and stall for time. TVs are notorious for
+ * requiring longer than specified to complete their replies.
*/
if (!intel_sdvo_read_byte(intel_sdvo,
SDVO_I2C_CMD_STATUS,
&status))
goto log_fail;
- while (status == SDVO_CMD_STATUS_PENDING && retry--) {
- udelay(15);
- if (!intel_sdvo_read_byte(intel_sdvo,
- SDVO_I2C_CMD_STATUS,
- &status))
- goto log_fail;
- }
+ do {
+ int quick = 5;
+
+ while (status == SDVO_CMD_STATUS_PENDING && quick--) {
+ udelay(15);
+ if (!intel_sdvo_read_byte(intel_sdvo,
+ SDVO_I2C_CMD_STATUS,
+ &status))
+ goto log_fail;
+ }
+
+ if (status != SDVO_CMD_STATUS_PENDING || --retry == 0)
+ break;
+
+ msleep(15);
+ } while (1);
if (status <= SDVO_CMD_STATUS_SCALING_NOT_SUPP)
DRM_LOG_KMS("(%s)", cmd_status_names[status]);
@@ -1535,15 +1548,9 @@ intel_sdvo_detect(struct drm_connector *connector, bool force)
struct intel_sdvo_connector *intel_sdvo_connector = to_intel_sdvo_connector(connector);
enum drm_connector_status ret;
- if (!intel_sdvo_write_cmd(intel_sdvo,
- SDVO_CMD_GET_ATTACHED_DISPLAYS, NULL, 0))
- return connector_status_unknown;
-
- /* add 30ms delay when the output type might be TV */
- if (intel_sdvo->caps.output_flags & SDVO_TV_MASK)
- msleep(30);
-
- if (!intel_sdvo_read_response(intel_sdvo, &response, 2))
+ if (!intel_sdvo_get_value(intel_sdvo,
+ SDVO_CMD_GET_ATTACHED_DISPLAYS,
+ &response, 2))
return connector_status_unknown;
DRM_DEBUG_KMS("SDVO response %d %d [%x]\n",