ALSA: hda - add DP mst verb support (13800f39) · Commits · 戴 / test

sound/pci/hda/hda_codec.c

+68 −4

Original line number	Diff line number	Diff line
		@@ -311,9 +311,15 @@ int snd_hda_get_conn_index(struct hda_codec *codec, hda_nid_t mux,
		}
		EXPORT_SYMBOL_GPL(snd_hda_get_conn_index);


		/* return DEVLIST_LEN parameter of the given widget */
		static unsigned int get_num_devices(struct hda_codec *codec, hda_nid_t nid)
		/**
		* snd_hda_get_num_devices - get DEVLIST_LEN parameter of the given widget
		* @codec: the HDA codec
		* @nid: NID of the pin to parse
		*
		* Get the device entry number on the given widget. This is a feature of
		* DP MST audio. Each pin can have several device entries in it.
		*/
		unsigned int snd_hda_get_num_devices(struct hda_codec *codec, hda_nid_t nid)
		{
		unsigned int wcaps = get_wcaps(codec, nid);
		unsigned int parm;
		@@ -327,6 +333,7 @@ static unsigned int get_num_devices(struct hda_codec *codec, hda_nid_t nid)
		parm = 0;
		return parm & AC_DEV_LIST_LEN_MASK;
		}
		EXPORT_SYMBOL_GPL(snd_hda_get_num_devices);

		/**
		* snd_hda_get_devices - copy device list without cache
		@@ -344,7 +351,7 @@ int snd_hda_get_devices(struct hda_codec *codec, hda_nid_t nid,
		unsigned int parm;
		int i, dev_len, devices;

		parm = get_num_devices(codec, nid);
		parm = snd_hda_get_num_devices(codec, nid);
		if (!parm) /* not multi-stream capable */
		return 0;

		@@ -368,6 +375,63 @@ 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.
		*/
		int snd_hda_set_dev_select(struct hda_codec *codec, hda_nid_t nid, int dev_id)
		{
		int ret, num_devices;

		/* not support dp_mst will always return 0, using first dev_entry */
		if (!codec->dp_mst)
		return 0;

		/* AC_PAR_DEVLIST_LEN is 0 based. */
		num_devices = snd_hda_get_num_devices(codec, nid) + 1;
		/* If Device List Length is 0 (num_device = 1),
		* the pin is not multi stream capable.
		* Do nothing in this case.
		*/
		if (num_devices == 1)
		return 0;

		/* Behavior of setting index being equal to or greater than
		* Device List Length is not predictable
		*/
		if (num_devices <= dev_id)
		return -EINVAL;

		ret = snd_hda_codec_write(codec, nid, 0,
		AC_VERB_SET_DEVICE_SEL, dev_id);

		return ret;
		}
		EXPORT_SYMBOL_GPL(snd_hda_set_dev_select);

		/*
		* read widget caps for each widget and store in cache
		*/

sound/pci/hda/hda_codec.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -347,8 +347,11 @@ int snd_hda_override_conn_list(struct hda_codec *codec, hda_nid_t nid, int nums,
		const hda_nid_t *list);
		int snd_hda_get_conn_index(struct hda_codec *codec, hda_nid_t mux,
		hda_nid_t nid, int recursive);
		unsigned int snd_hda_get_num_devices(struct hda_codec *codec, hda_nid_t nid);
		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;

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