On Wed, 13 Jan 2016 12:09:49 +0100, libin.yang@linux.intel.com wrote:
From: Libin Yang libin.yang@linux.intel.com
Add snd_hda_get_dev_select() and snd_hda_set_dev_select() functions for DP MST audio support.
Signed-off-by: Libin Yang libin.yang@linux.intel.com
sound/pci/hda/hda_codec.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++ sound/pci/hda/hda_codec.h | 2 ++ 2 files changed, 56 insertions(+)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c index 8374188..95baaba 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -368,6 +368,60 @@ int snd_hda_get_devices(struct hda_codec *codec, hda_nid_t nid, return devices; }
+/**
- snd_hda_get_dev_select - get device entry select on the pin
- @codec: the HDA codec
- @nid: NID of the pin to get device entry select
- Get the devcie entry select on the pin. Return the device entry
- id selected on the pin. Return 0 means the first device entry
- is selected or MST is not supported.
- */
+int snd_hda_get_dev_select(struct hda_codec *codec, hda_nid_t nid) +{
- /* not support dp_mst will always return 0, using first dev_entry */
- if (!codec->dp_mst)
return 0;- return snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_DEVICE_SEL, 0);
+} +EXPORT_SYMBOL_GPL(snd_hda_get_dev_select);
+/**
- snd_hda_set_dev_select - set device entry select on the pin
- @codec: the HDA codec
- @nid: NID of the pin to set device entry select
- @dev_id: device entry id to be set
- Set the device entry select on the pin nid.
The return code isn't clearly defined.
Other than that, it looks OK. But I prefer merging this rather together with its caller (unless a complex dependency exists).
thanks,
Takashi
- */
+int snd_hda_set_dev_select(struct hda_codec *codec, hda_nid_t nid, int dev_id) +{
- int ret, dev;
- unsigned long timeout;
- /* not support dp_mst will always return 0, using first dev_entry */
- if (!codec->dp_mst)
return 0;- timeout = jiffies + msecs_to_jiffies(500);
- /* make sure the device entry selection takes effect */
- do {
ret = snd_hda_codec_write(codec, nid, 0,AC_VERB_SET_DEVICE_SEL, dev_id);udelay(20);dev = snd_hda_get_dev_select(codec, nid);if (dev == dev_id)break;msleep(20);- } while (time_before(jiffies, timeout));
- return ret;
+} +EXPORT_SYMBOL_GPL(snd_hda_set_dev_select);
/*
- read widget caps for each widget and store in cache
*/ diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h index 373fcad..22bcad6 100644 --- a/sound/pci/hda/hda_codec.h +++ b/sound/pci/hda/hda_codec.h @@ -349,6 +349,8 @@ int snd_hda_get_conn_index(struct hda_codec *codec, hda_nid_t mux, hda_nid_t nid, int recursive); int snd_hda_get_devices(struct hda_codec *codec, hda_nid_t nid, u8 *dev_list, int max_devices); +int snd_hda_get_dev_select(struct hda_codec *codec, hda_nid_t nid); +int snd_hda_set_dev_select(struct hda_codec *codec, hda_nid_t nid, int dev_id);
struct hda_verb { hda_nid_t nid; -- 1.9.1