diff options
| author | Libin Yang <libin.yang@linux.intel.com> | 2017-01-12 16:04:53 +0800 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-01-12 10:06:47 +0100 |
| commit | 9152085defb6426ce8f9989ca27e4450daefbd89 (patch) | |
| tree | 91c90685a96ca5d47f1a02b41da2e44f2c07e52a /sound/pci/hda/hda_codec.c | |
| parent | 13800f397ee3b4996f316b9caa8482cb90edef0d (diff) | |
ALSA: hda - add DP MST audio support
This patch adds the DP MST audio support on i915 platform and
it will enable dyn_pcm_assign feature.
DP MST supports several device entry on the same port and each
device entry can map to one pcm stream. For example, on i915,
there are 3 pins, and each pin has 3 device entries. This means
there should be 3x3 pcms. However, there is only 3 pipe lines in
i915. This means 3 pcms are actived at most at the same moment.
We will create 5 pcms (pin number + dev entry num - 1) in this case.
For the details, please refer commit a76056f2e57e
("ALSA: hda - hdmi dynamically bind PCM to pin when monitor hotplug")
Each device entry is a virtual pin. It is described by pin_nid and dev_id
in struct hdmi_spec_per_pin.
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Libin Yang <libin.yang@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1484208294-8637-3-git-send-email-libin.yang@intel.com
Diffstat (limited to 'sound/pci/hda/hda_codec.c')
| -rw-r--r-- | sound/pci/hda/hda_codec.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c index 9dc847db1cc4..8fd745cb3f36 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -467,6 +467,10 @@ static int read_pin_defaults(struct hda_codec *codec) pin->nid = nid; pin->cfg = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_CONFIG_DEFAULT, 0); + /* + * all device entries are the same widget control so far + * fixme: if any codec is different, need fix here + */ pin->ctrl = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_PIN_WIDGET_CONTROL, 0); |