1 files changed, 19 insertions, 9 deletions

diff --git a/sound/pci/hda/hda_eld.c b/sound/pci/hda/hda_eld.c
index 7ae7578bdcc0..c1da422e085a 100644
--- a/sound/pci/hda/hda_eld.c
+++ b/sound/pci/hda/hda_eld.c
@@ -347,18 +347,28 @@ int snd_hdmi_get_eld(struct hdmi_eld *eld,
 
         for (i = 0; i < size; i++) {
                 unsigned int val = hdmi_get_eld_data(codec, nid, i);
+                /*
+                 * Graphics driver might be writing to ELD buffer right now.
+                 * Just abort. The caller will repoll after a while.
+                 */
                 if (!(val & AC_ELDD_ELD_VALID)) {
-                        if (!i) {
-                                snd_printd(KERN_INFO
-                                           "HDMI: invalid ELD data\n");
-                                ret = -EINVAL;
-                                goto error;
-                        }
                         snd_printd(KERN_INFO
                                   "HDMI: invalid ELD data byte %d\n", i);
-                        val = 0;
-                } else
-                        val &= AC_ELDD_ELD_DATA;
+                        ret = -EINVAL;
+                        goto error;
+                }
+                val &= AC_ELDD_ELD_DATA;
+                /*
+                 * The first byte cannot be zero. This can happen on some DVI
+                 * connections. Some Intel chips may also need some 250ms delay
+                 * to return non-zero ELD data, even when the graphics driver
+                 * correctly writes ELD content before setting ELD_valid bit.
+                 */
+                if (!val && !i) {
+                        snd_printdd(KERN_INFO "HDMI: 0 ELD data\n");
+                        ret = -EINVAL;
+                        goto error;
+                }
                 buf[i] = val;
         }