ALSA: hda - Cache the jack-detection value

Introduce a table containing the pins and their jack-detection states
for avoiding the unnecessary verbs to check the pin status at each time.

When the unsol event is enabled via snd_hda_jack_detect_enable(), it
automatically adds the given NID to the table.  Then the driver supposes
that the codec driver will set the dirty flag appropariately when an
unsolicited event is invoked for that pin.

The behavior for reading other pins that aren't registered in the table
doesn't change.  Only the pins assigned to the table are cached, so far.

In near futre, this table can be extended to use the central place for
the unsolicited events of all pins, etc, and eventually include the
jack-detect kcontrols that replace the current input-jack stuff.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 148 insertions, 0 deletions

diff --git a/sound/pci/hda/hda_jack.c b/sound/pci/hda/hda_jack.c
new file mode 100644
index 000000000000..64b78a2e20e0
--- /dev/null
+++ b/sound/pci/hda/hda_jack.c
@@ -0,0 +1,148 @@
+/*
+ * Jack-detection handling for HD-audio
+ *
+ * Copyright (c) 2011 Takashi Iwai <tiwai@suse.de>
+ *
+ * This driver is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include "hda_codec.h"
+#include "hda_local.h"
+#include "hda_jack.h"
+
+/* execute pin sense measurement */
+static u32 read_pin_sense(struct hda_codec *codec, hda_nid_t nid)
+{
+	u32 pincap;
+
+	if (!codec->no_trigger_sense) {
+		pincap = snd_hda_query_pin_caps(codec, nid);
+		if (pincap & AC_PINCAP_TRIG_REQ) /* need trigger? */
+			snd_hda_codec_read(codec, nid, 0,
+					AC_VERB_SET_PIN_SENSE, 0);
+	}
+	return snd_hda_codec_read(codec, nid, 0,
+				  AC_VERB_GET_PIN_SENSE, 0);
+}
+
+/**
+ * snd_hda_jack_tbl_get - query the jack-table entry for the given NID
+ */
+struct hda_jack_tbl *
+snd_hda_jack_tbl_get(struct hda_codec *codec, hda_nid_t nid)
+{
+	struct hda_jack_tbl *jack = codec->jacktbl.list;
+	int i;
+
+	if (!nid || !jack)
+		return NULL;
+	for (i = 0; i < codec->jacktbl.used; i++, jack++)
+		if (jack->nid == nid)
+			return jack;
+	return NULL;
+}
+EXPORT_SYMBOL_HDA(snd_hda_jack_tbl_get);
+
+/**
+ * snd_hda_jack_tbl_new - create a jack-table entry for the given NID
+ */
+struct hda_jack_tbl *
+snd_hda_jack_tbl_new(struct hda_codec *codec, hda_nid_t nid)
+{
+	struct hda_jack_tbl *jack = snd_hda_jack_tbl_get(codec, nid);
+	if (jack)
+		return jack;
+	snd_array_init(&codec->jacktbl, sizeof(*jack), 16);
+	jack = snd_array_new(&codec->jacktbl);
+	if (!jack)
+		return NULL;
+	jack->nid = nid;
+	jack->jack_dirty = 1;
+	return jack;
+}
+
+void snd_hda_jack_tbl_clear(struct hda_codec *codec)
+{
+	snd_array_free(&codec->jacktbl);
+}
+
+/* update the cached value and notification flag if needed */
+static void jack_detect_update(struct hda_codec *codec,
+			       struct hda_jack_tbl *jack)
+{
+	if (jack->jack_dirty) {
+		jack->pin_sense = read_pin_sense(codec, jack->nid);
+		jack->jack_dirty = 0;
+	}
+}
+
+/**
+ * snd_hda_set_dirty_all - Mark all the cached as dirty
+ *
+ * This function sets the dirty flag to all entries of jack table.
+ * It's called from the resume path in hda_codec.c.
+ */
+void snd_hda_jack_set_dirty_all(struct hda_codec *codec)
+{
+	struct hda_jack_tbl *jack = codec->jacktbl.list;
+	int i;
+
+	for (i = 0; i < codec->jacktbl.used; i++, jack++)
+		if (jack->nid)
+			jack->jack_dirty = 1;
+}
+EXPORT_SYMBOL_HDA(snd_hda_jack_set_dirty_all);
+
+/**
+ * snd_hda_pin_sense - execute pin sense measurement
+ * @codec: the CODEC to sense
+ * @nid: the pin NID to sense
+ *
+ * Execute necessary pin sense measurement and return its Presence Detect,
+ * Impedance, ELD Valid etc. status bits.
+ */
+u32 snd_hda_pin_sense(struct hda_codec *codec, hda_nid_t nid)
+{
+	struct hda_jack_tbl *jack = snd_hda_jack_tbl_get(codec, nid);
+	if (jack) {
+		jack_detect_update(codec, jack);
+		return jack->pin_sense;
+	}
+	return read_pin_sense(codec, nid);
+}
+EXPORT_SYMBOL_HDA(snd_hda_pin_sense);
+
+/**
+ * snd_hda_jack_detect - query pin Presence Detect status
+ * @codec: the CODEC to sense
+ * @nid: the pin NID to sense
+ *
+ * Query and return the pin's Presence Detect status.
+ */
+int snd_hda_jack_detect(struct hda_codec *codec, hda_nid_t nid)
+{
+	u32 sense = snd_hda_pin_sense(codec, nid);
+	return !!(sense & AC_PINSENSE_PRESENCE);
+}
+EXPORT_SYMBOL_HDA(snd_hda_jack_detect);
+
+/**
+ * snd_hda_jack_detect_enable - enable the jack-detection
+ */
+int snd_hda_jack_detect_enable(struct hda_codec *codec, hda_nid_t nid,
+			       unsigned int tag)
+{
+	struct hda_jack_tbl *jack = snd_hda_jack_tbl_new(codec, nid);
+	if (!jack)
+		return -ENOMEM;
+	return snd_hda_codec_write_cache(codec, nid, 0,
+					 AC_VERB_SET_UNSOLICITED_ENABLE,
+					 AC_USRSP_EN | tag);
+}
+EXPORT_SYMBOL_HDA(snd_hda_jack_detect_enable);