[alsa-devel] Applied "ASoC: hdac_hdmi: Add MST verb support" to the asoc tree

[Mark Brown]

The patch

   ASoC: hdac_hdmi: Add MST verb support

has been applied to the asoc tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From fc181b04f2d44805624d4bc5a0615bc084199a81 Mon Sep 17 00:00:00 2001
From: Jeeja KP <jeeja.kp at intel.com>
Date: Tue, 7 Feb 2017 19:09:45 +0530
Subject: [PATCH] ASoC: hdac_hdmi: Add MST verb support

To support DP MST audio, new pin verbs/params are added. This patch
adds helper functions to do following:
o To set a specific port
o To get the currently selected port
o To get the length of port.

Signed-off-by: Jeeja KP <jeeja.kp at intel.com>
Acked-by: Vinod Koul <vinod.koul at intel.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/codecs/hdac_hdmi.c | 70 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 70 insertions(+)

diff --git a/sound/soc/codecs/hdac_hdmi.c b/sound/soc/codecs/hdac_hdmi.c
index 17a1ad3ead21..84b7d6cd7c37 100644
--- a/sound/soc/codecs/hdac_hdmi.c
+++ b/sound/soc/codecs/hdac_hdmi.c
@@ -142,6 +142,76 @@ hdac_hdmi_get_pcm_from_cvt(struct hdac_hdmi_priv *hdmi,
 	return pcm;
 }
 
+/* MST supported verbs */
+/*
+ * Get the no devices that can be connected to a port on the Pin widget.
+ */
+static int hdac_hdmi_get_port_len(struct hdac_ext_device *hdac, hda_nid_t nid)
+{
+	unsigned int caps;
+	unsigned int type, param;
+
+	caps = get_wcaps(&hdac->hdac, nid);
+	type = get_wcaps_type(caps);
+
+	if (!(caps & AC_WCAP_DIGITAL) || (type != AC_WID_PIN))
+		return 0;
+
+	param = snd_hdac_read_parm_uncached(&hdac->hdac, nid,
+					AC_PAR_DEVLIST_LEN);
+	if (param == -1)
+		return param;
+
+	return param & AC_DEV_LIST_LEN_MASK;
+}
+
+/*
+ * Get the port entry select on the pin. Return the port entry
+ * id selected on the pin. Return 0 means the first port entry
+ * is selected or MST is not supported.
+ */
+static int hdac_hdmi_port_select_get(struct hdac_ext_device *hdac,
+					struct hdac_hdmi_port *port)
+{
+	return snd_hdac_codec_read(&hdac->hdac, port->pin->nid,
+				0, AC_VERB_GET_DEVICE_SEL, 0);
+}
+
+/*
+ * Sets the selected port entry for the configuring Pin widget verb.
+ * returns error if port set is not equal to port get otherwise success
+ */
+static int hdac_hdmi_port_select_set(struct hdac_ext_device *hdac,
+					struct hdac_hdmi_port *port)
+{
+	int num_ports;
+
+	if (!port->pin->mst_capable)
+		return 0;
+
+	/* AC_PAR_DEVLIST_LEN is 0 based. */
+	num_ports = hdac_hdmi_get_port_len(hdac, port->pin->nid);
+
+	if (num_ports < 0)
+		return -EIO;
+	/*
+	 * Device List Length is a 0 based integer value indicating the
+	 * number of sink device that a MST Pin Widget can support.
+	 */
+	if (num_ports + 1  < port->id)
+		return 0;
+
+	snd_hdac_codec_write(&hdac->hdac, port->pin->nid, 0,
+			AC_VERB_SET_DEVICE_SEL, port->id);
+
+	if (port->id != hdac_hdmi_port_select_get(hdac, port))
+		return -EIO;
+
+	dev_dbg(&hdac->hdac.dev, "Selected the port=%d\n", port->id);
+
+	return 0;
+}
+
 static struct hdac_hdmi_pcm *get_hdmi_pcm_from_id(struct hdac_hdmi_priv *hdmi,
 						int pcm_idx)
 {
-- 
2.11.0