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>

3 files changed, 59 insertions, 0 deletions

diff --git a/sound/core/Kconfig b/sound/core/Kconfig
index 475455c76610..66f287f2f759 100644
--- a/sound/core/Kconfig
+++ b/sound/core/Kconfig
@@ -207,6 +207,9 @@ config SND_PCM_XRUN_DEBUG
 config SND_VMASTER
         bool
 
+config SND_KCTL_JACK
+        bool
+
 config SND_DMA_SGBUF
         def_bool y
         depends on X86
diff --git a/sound/core/Makefile b/sound/core/Makefile
index 350a08d277f4..b4637c3e776e 100644
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -7,6 +7,7 @@ snd-y     := sound.o init.o memory.o info.o control.o misc.o device.o
 snd-$(CONFIG_ISA_DMA_API) += isadma.o
 snd-$(CONFIG_SND_OSSEMUL) += sound_oss.o info_oss.o
 snd-$(CONFIG_SND_VMASTER) += vmaster.o
+snd-$(CONFIG_SND_KCTL_JACK) += ctljack.o
 snd-$(CONFIG_SND_JACK)    += jack.o
 
 snd-pcm-objs := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \
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);