The Intel HDMI chips (ironlake at least) are found to have ~250ms delay between the ELD_Valid=1 hotplug event is send and the ELD buffer becomes actually readable. During the time the ELD buffer is mysteriously all 0. Fix it by scheduling a delayed work to re-read ELD buffer after 300ms. Signed-off-by: Wu Fengguang <fengguang.wu at intel.com> --- sound/pci/hda/hda_local.h | 2 + sound/pci/hda/patch_hdmi.c | 49 ++++++++++++++++++++++++++++++----- 2 files changed, 44 insertions(+), 7 deletions(-) --- linux.orig/sound/pci/hda/hda_local.h 2011-11-15 21:29:53.000000000 +0800 +++ linux/sound/pci/hda/hda_local.h 2011-11-15 21:29:54.000000000 +0800 @@ -655,6 +655,8 @@ struct hdmi_eld { #ifdef CONFIG_PROC_FS struct snd_info_entry *proc_entry; #endif + struct hda_codec *codec; + struct delayed_work work; }; int snd_hdmi_get_eld_size(struct hda_codec *codec, hda_nid_t nid); --- linux.orig/sound/pci/hda/patch_hdmi.c 2011-11-15 21:29:53.000000000 +0800 +++ linux/sound/pci/hda/patch_hdmi.c 2011-11-15 21:31:48.000000000 +0800 @@ -746,7 +746,7 @@ static void hdmi_setup_audio_infoframe(s */ static void hdmi_present_sense(struct hda_codec *codec, hda_nid_t pin_nid, - struct hdmi_eld *eld); + struct hdmi_eld *eld, bool retry); static void hdmi_intrinsic_event(struct hda_codec *codec, unsigned int res) { @@ -766,7 +766,7 @@ static void hdmi_intrinsic_event(struct return; eld = &spec->pins[pin_idx].sink_eld; - hdmi_present_sense(codec, pin_nid, eld); + hdmi_present_sense(codec, pin_nid, eld, true); /* * HDMI sink's ELD info cannot always be retrieved for now, e.g. @@ -969,7 +969,7 @@ static int hdmi_read_pin_conn(struct hda } static void hdmi_present_sense(struct hda_codec *codec, hda_nid_t pin_nid, - struct hdmi_eld *eld) + struct hdmi_eld *eld, bool retry) { /* * Always execute a GetPinSense verb here, even when called from @@ -992,13 +992,31 @@ static void hdmi_present_sense(struct hd "HDMI status: Codec=%d Pin=%d Presence_Detect=%d ELD_Valid=%d\n", codec->addr, pin_nid, eld->monitor_present, eld_valid); - if (eld_valid) + if (eld_valid) { if (!snd_hdmi_get_eld(eld, codec, pin_nid)) snd_hdmi_show_eld(eld); + else { + queue_delayed_work(codec->bus->workq, + &eld->work, + msecs_to_jiffies(300)); + } + } snd_hda_input_jack_report(codec, pin_nid); } +static void hda_eld_work(struct work_struct *work) +{ + struct hdmi_eld *eld = container_of( + container_of(work, struct delayed_work, work), + struct hdmi_eld, work); + struct hdmi_spec_per_pin *per_pin = + container_of(eld, struct hdmi_spec_per_pin, sink_eld); + struct hda_codec *codec = eld->codec; + + hdmi_present_sense(codec, per_pin->pin_nid, eld, false); +} + static int hdmi_add_pin(struct hda_codec *codec, hda_nid_t pin_nid) { struct hdmi_spec *spec = codec->spec; @@ -1227,7 +1245,7 @@ static int generic_hdmi_build_jack(struc if (err < 0) return err; - hdmi_present_sense(codec, per_pin->pin_nid, &per_pin->sink_eld); + hdmi_present_sense(codec, per_pin->pin_nid, &per_pin->sink_eld, false); return 0; } @@ -1263,6 +1281,23 @@ static int generic_hdmi_build_controls(s return 0; } +static void snd_hda_eld_init(struct hda_codec *codec, struct hdmi_eld *eld, + int pin_idx) +{ + eld->codec = codec; + INIT_DELAYED_WORK(&eld->work, hda_eld_work); + + snd_hda_eld_proc_new(codec, eld, pin_idx); +} + +static void snd_hda_eld_free(struct hda_codec *codec, struct hdmi_eld *eld) +{ + cancel_delayed_work(&eld->work); + flush_workqueue(codec->bus->workq); + + snd_hda_eld_proc_free(codec, eld); +} + static int generic_hdmi_init(struct hda_codec *codec) { struct hdmi_spec *spec = codec->spec; @@ -1278,7 +1313,7 @@ static int generic_hdmi_init(struct hda_ AC_VERB_SET_UNSOLICITED_ENABLE, AC_USRSP_EN | pin_nid); - snd_hda_eld_proc_new(codec, eld, pin_idx); + snd_hda_eld_init(codec, eld, pin_idx); } return 0; } @@ -1292,7 +1327,7 @@ static void generic_hdmi_free(struct hda struct hdmi_spec_per_pin *per_pin = &spec->pins[pin_idx]; struct hdmi_eld *eld = &per_pin->sink_eld; - snd_hda_eld_proc_free(codec, eld); + snd_hda_eld_free(codec, eld); } snd_hda_input_jack_free(codec);