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path: root/drivers/gpu/drm/drm_edid.c
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Diffstat (limited to 'drivers/gpu/drm/drm_edid.c')
-rw-r--r--drivers/gpu/drm/drm_edid.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 7425e5c9bd75..3e927ce7557d 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -30,6 +30,7 @@
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/i2c.h>
+#include <linux/export.h>
#include "drmP.h"
#include "drm_edid.h"
#include "drm_edid_modes.h"
@@ -1319,6 +1320,7 @@ add_detailed_modes(struct drm_connector *connector, struct edid *edid,
#define HDMI_IDENTIFIER 0x000C03
#define AUDIO_BLOCK 0x01
#define VENDOR_BLOCK 0x03
+#define SPEAKER_BLOCK 0x04
#define EDID_BASIC_AUDIO (1 << 6)
/**
@@ -1347,6 +1349,176 @@ u8 *drm_find_cea_extension(struct edid *edid)
}
EXPORT_SYMBOL(drm_find_cea_extension);
+static void
+parse_hdmi_vsdb(struct drm_connector *connector, uint8_t *db)
+{
+ connector->eld[5] |= (db[6] >> 7) << 1; /* Supports_AI */
+
+ connector->dvi_dual = db[6] & 1;
+ connector->max_tmds_clock = db[7] * 5;
+
+ connector->latency_present[0] = db[8] >> 7;
+ connector->latency_present[1] = (db[8] >> 6) & 1;
+ connector->video_latency[0] = db[9];
+ connector->audio_latency[0] = db[10];
+ connector->video_latency[1] = db[11];
+ connector->audio_latency[1] = db[12];
+
+ DRM_LOG_KMS("HDMI: DVI dual %d, "
+ "max TMDS clock %d, "
+ "latency present %d %d, "
+ "video latency %d %d, "
+ "audio latency %d %d\n",
+ connector->dvi_dual,
+ connector->max_tmds_clock,
+ (int) connector->latency_present[0],
+ (int) connector->latency_present[1],
+ connector->video_latency[0],
+ connector->video_latency[1],
+ connector->audio_latency[0],
+ connector->audio_latency[1]);
+}
+
+static void
+monitor_name(struct detailed_timing *t, void *data)
+{
+ if (t->data.other_data.type == EDID_DETAIL_MONITOR_NAME)
+ *(u8 **)data = t->data.other_data.data.str.str;
+}
+
+/**
+ * drm_edid_to_eld - build ELD from EDID
+ * @connector: connector corresponding to the HDMI/DP sink
+ * @edid: EDID to parse
+ *
+ * Fill the ELD (EDID-Like Data) buffer for passing to the audio driver.
+ * Some ELD fields are left to the graphics driver caller:
+ * - Conn_Type
+ * - HDCP
+ * - Port_ID
+ */
+void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
+{
+ uint8_t *eld = connector->eld;
+ u8 *cea;
+ u8 *name;
+ u8 *db;
+ int sad_count = 0;
+ int mnl;
+ int dbl;
+
+ memset(eld, 0, sizeof(connector->eld));
+
+ cea = drm_find_cea_extension(edid);
+ if (!cea) {
+ DRM_DEBUG_KMS("ELD: no CEA Extension found\n");
+ return;
+ }
+
+ name = NULL;
+ drm_for_each_detailed_block((u8 *)edid, monitor_name, &name);
+ for (mnl = 0; name && mnl < 13; mnl++) {
+ if (name[mnl] == 0x0a)
+ break;
+ eld[20 + mnl] = name[mnl];
+ }
+ eld[4] = (cea[1] << 5) | mnl;
+ DRM_DEBUG_KMS("ELD monitor %s\n", eld + 20);
+
+ eld[0] = 2 << 3; /* ELD version: 2 */
+
+ eld[16] = edid->mfg_id[0];
+ eld[17] = edid->mfg_id[1];
+ eld[18] = edid->prod_code[0];
+ eld[19] = edid->prod_code[1];
+
+ for (db = cea + 4; db < cea + cea[2]; db += dbl + 1) {
+ dbl = db[0] & 0x1f;
+
+ switch ((db[0] & 0xe0) >> 5) {
+ case AUDIO_BLOCK: /* Audio Data Block, contains SADs */
+ sad_count = dbl / 3;
+ memcpy(eld + 20 + mnl, &db[1], dbl);
+ break;
+ case SPEAKER_BLOCK: /* Speaker Allocation Data Block */
+ eld[7] = db[1];
+ break;
+ case VENDOR_BLOCK:
+ /* HDMI Vendor-Specific Data Block */
+ if (db[1] == 0x03 && db[2] == 0x0c && db[3] == 0)
+ parse_hdmi_vsdb(connector, db);
+ break;
+ default:
+ break;
+ }
+ }
+ eld[5] |= sad_count << 4;
+ eld[2] = (20 + mnl + sad_count * 3 + 3) / 4;
+
+ DRM_DEBUG_KMS("ELD size %d, SAD count %d\n", (int)eld[2], sad_count);
+}
+EXPORT_SYMBOL(drm_edid_to_eld);
+
+/**
+ * drm_av_sync_delay - HDMI/DP sink audio-video sync delay in millisecond
+ * @connector: connector associated with the HDMI/DP sink
+ * @mode: the display mode
+ */
+int drm_av_sync_delay(struct drm_connector *connector,
+ struct drm_display_mode *mode)
+{
+ int i = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
+ int a, v;
+
+ if (!connector->latency_present[0])
+ return 0;
+ if (!connector->latency_present[1])
+ i = 0;
+
+ a = connector->audio_latency[i];
+ v = connector->video_latency[i];
+
+ /*
+ * HDMI/DP sink doesn't support audio or video?
+ */
+ if (a == 255 || v == 255)
+ return 0;
+
+ /*
+ * Convert raw EDID values to millisecond.
+ * Treat unknown latency as 0ms.
+ */
+ if (a)
+ a = min(2 * (a - 1), 500);
+ if (v)
+ v = min(2 * (v - 1), 500);
+
+ return max(v - a, 0);
+}
+EXPORT_SYMBOL(drm_av_sync_delay);
+
+/**
+ * drm_select_eld - select one ELD from multiple HDMI/DP sinks
+ * @encoder: the encoder just changed display mode
+ * @mode: the adjusted display mode
+ *
+ * It's possible for one encoder to be associated with multiple HDMI/DP sinks.
+ * The policy is now hard coded to simply use the first HDMI/DP sink's ELD.
+ */
+struct drm_connector *drm_select_eld(struct drm_encoder *encoder,
+ struct drm_display_mode *mode)
+{
+ struct drm_connector *connector;
+ struct drm_device *dev = encoder->dev;
+
+ list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+ if (connector->encoder == encoder && connector->eld[0])
+ return connector;
+
+ return NULL;
+}
+EXPORT_SYMBOL(drm_select_eld);
+
/**
* drm_detect_hdmi_monitor - detect whether monitor is hdmi.
* @edid: monitor EDID information