ALSA: Introduce common helper functions for jack-detection control

Now move the helper function for creating and reporting the jack-detection
to the common place.  The driver that needs this functionality should
select CONFIG_SND_KCTL_JACK kconfig.

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

1 files changed, 55 insertions, 0 deletions

diff --git a/sound/core/ctljack.c b/sound/core/ctljack.c
new file mode 100644
index 000000000000..af0e78a3809c
--- /dev/null
+++ b/sound/core/ctljack.c
@@ -0,0 +1,55 @@
+/*
+ * Helper functions for jack-detection kcontrols
+ *
+ * Copyright (c) 2011 Takashi Iwai <tiwai@suse.de>
+ *
+ * This program 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/kernel.h>
+#include <sound/core.h>
+#include <sound/control.h>
+
+#define jack_detect_kctl_info	snd_ctl_boolean_mono_info
+
+static int jack_detect_kctl_get(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_value *ucontrol)
+{
+	ucontrol->value.integer.value[0] = kcontrol->private_value;
+	return 0;
+}
+
+static struct snd_kcontrol_new jack_detect_kctl = {
+	/* name is filled later */
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.access = SNDRV_CTL_ELEM_ACCESS_READ,
+	.info = jack_detect_kctl_info,
+	.get = jack_detect_kctl_get,
+};
+
+struct snd_kcontrol *
+snd_kctl_jack_new(const char *name, int idx, void *private_data)
+{
+	struct snd_kcontrol *kctl;
+	kctl = snd_ctl_new1(&jack_detect_kctl, private_data);
+	if (!kctl)
+		return NULL;
+	snprintf(kctl->id.name, sizeof(kctl->id.name), "%s Jack", name);
+	kctl->id.index = idx;
+	kctl->private_value = 0;
+	return kctl;
+}
+EXPORT_SYMBOL_GPL(snd_kctl_jack_new);
+
+void snd_kctl_jack_report(struct snd_card *card,
+			  struct snd_kcontrol *kctl, bool status)
+{
+	if (kctl->private_value == status)
+		return;
+	kctl->private_value = status;
+	snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, &kctl->id);
+}
+EXPORT_SYMBOL_GPL(snd_kctl_jack_report);