ALSA: hda/hdmi: expose ELD control
Applications may want to read ELD information to
understand what codecs are supported on the HDMI
receiver and handle the a-v delay for better lip-sync.
ELD information is exposed in a device-specific
IFACE_PCM kcontrol. Tested both with amixer and
PulseAudio; with a corresponding patch passthrough modes
are enabled automagically.
ELD control size is set to zero in case of errors or
wrong configurations. No notifications are implemented
for now, it is expected that jack detection is used to
reconfigure the audio outputs.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_eld.c b/sound/pci/hda/hda_eld.c
index c34f730..f1c621d 100644
--- a/sound/pci/hda/hda_eld.c
+++ b/sound/pci/hda/hda_eld.c
@@ -318,6 +318,11 @@
int size;
unsigned char *buf;
+ /*
+ * ELD size is initialized to zero in caller function. If no errors and
+ * ELD is valid, actual eld_size is assigned in hdmi_update_eld()
+ */
+
if (!eld->eld_valid)
return -ENOENT;
@@ -327,14 +332,13 @@
snd_printd(KERN_INFO "HDMI: ELD buf size is 0, force 128\n");
size = 128;
}
- if (size < ELD_FIXED_BYTES || size > PAGE_SIZE) {
+ if (size < ELD_FIXED_BYTES || size > ELD_MAX_SIZE) {
snd_printd(KERN_INFO "HDMI: invalid ELD buf size %d\n", size);
return -ERANGE;
}
- buf = kmalloc(size, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
+ /* set ELD buffer */
+ buf = eld->eld_buffer;
for (i = 0; i < size; i++) {
unsigned int val = hdmi_get_eld_data(codec, nid, i);
@@ -356,7 +360,6 @@
ret = hdmi_update_eld(eld, buf, size);
error:
- kfree(buf);
return ret;
}
diff --git a/sound/pci/hda/hda_local.h b/sound/pci/hda/hda_local.h
index aaefa7c..04d730f 100644
--- a/sound/pci/hda/hda_local.h
+++ b/sound/pci/hda/hda_local.h
@@ -621,6 +621,7 @@
};
#define ELD_FIXED_BYTES 20
+#define ELD_MAX_SIZE 256
#define ELD_MAX_MNL 16
#define ELD_MAX_SAD 16
@@ -645,6 +646,7 @@
int spk_alloc;
int sad_count;
struct cea_sad sad[ELD_MAX_SAD];
+ char eld_buffer[ELD_MAX_SIZE];
#ifdef CONFIG_PROC_FS
struct snd_info_entry *proc_entry;
#endif
diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 3f1f6ac..3425401 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -324,6 +324,66 @@
return -EINVAL;
}
+static int hdmi_eld_ctl_info(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_info *uinfo)
+{
+ struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
+ struct hdmi_spec *spec;
+ int pin_idx;
+
+ spec = codec->spec;
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES;
+
+ pin_idx = kcontrol->private_value;
+ uinfo->count = spec->pins[pin_idx].sink_eld.eld_size;
+
+ return 0;
+}
+
+static int hdmi_eld_ctl_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
+ struct hdmi_spec *spec;
+ int pin_idx;
+
+ spec = codec->spec;
+ pin_idx = kcontrol->private_value;
+
+ memcpy(ucontrol->value.bytes.data,
+ spec->pins[pin_idx].sink_eld.eld_buffer, ELD_MAX_SIZE);
+
+ return 0;
+}
+
+static struct snd_kcontrol_new eld_bytes_ctl = {
+ .access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+ .name = "ELD",
+ .info = hdmi_eld_ctl_info,
+ .get = hdmi_eld_ctl_get,
+};
+
+static int hdmi_create_eld_ctl(struct hda_codec *codec, int pin_idx,
+ int device)
+{
+ struct snd_kcontrol *kctl;
+ struct hdmi_spec *spec = codec->spec;
+ int err;
+
+ kctl = snd_ctl_new1(&eld_bytes_ctl, codec);
+ if (!kctl)
+ return -ENOMEM;
+ kctl->private_value = pin_idx;
+ kctl->id.device = device;
+
+ err = snd_hda_ctl_add(codec, spec->pins[pin_idx].pin_nid, kctl);
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
#ifdef BE_PARANOID
static void hdmi_get_dip_index(struct hda_codec *codec, hda_nid_t pin_nid,
int *packet_index, int *byte_index)
@@ -1193,6 +1253,14 @@
if (err < 0)
return err;
snd_hda_spdif_ctls_unassign(codec, pin_idx);
+
+ /* add control for ELD Bytes */
+ err = hdmi_create_eld_ctl(codec,
+ pin_idx,
+ spec->pcm_rec[pin_idx].device);
+
+ if (err < 0)
+ return err;
}
return 0;