ALSA: hda: digital pc-beep support hd-audio codecs

Added digital pc-beep support using linear tone generation for hd-codecs along
with initial support for several IDT codecs.

Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

1 files changed, 134 insertions, 0 deletions

diff --git a/sound/pci/hda/hda_beep.c b/sound/pci/hda/hda_beep.c
new file mode 100644
index 000000000000..5a764c481391
--- /dev/null
+++ b/sound/pci/hda/hda_beep.c
@@ -0,0 +1,134 @@
+/*
+ * Digital Beep Input Interface for HD-audio codec
+ *
+ * Author: Matthew Ranostay <mranostay@embeddedalley.com>
+ * Copyright (c) 2008 Embedded Alley Solutions Inc
+ *
+ *  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.
+ *
+ *  This driver is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/input.h>
+#include <linux/pci.h>
+#include <linux/workqueue.h>
+#include <sound/core.h>
+#include "hda_beep.h"
+
+enum {
+        DIGBEEP_HZ_STEP = 46875,        /* 46.875 Hz */
+        DIGBEEP_HZ_MIN = 93750,         /* 93.750 Hz */
+        DIGBEEP_HZ_MAX = 12000000,      /* 12 KHz */
+};
+
+static void snd_hda_generate_beep(struct work_struct *work)
+{
+        struct hda_beep *beep =
+                container_of(work, struct hda_beep, beep_work);
+        struct hda_codec *codec = beep->codec;
+
+        /* generate tone */
+        snd_hda_codec_write_cache(codec, beep->nid, 0,
+                        AC_VERB_SET_BEEP_CONTROL, beep->tone);
+}
+
+static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
+                                unsigned int code, int hz)
+{
+        struct hda_beep *beep = input_get_drvdata(dev);
+
+        switch (code) {
+        case SND_BELL:
+                if (hz)
+                        hz = 1000;
+        case SND_TONE:
+                hz *= 1000; /* fixed point */
+                hz = hz - DIGBEEP_HZ_MIN;
+                if (hz < 0)
+                        hz = 0; /* turn off PC beep*/
+                else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN))
+                        hz = 0xff;
+                else {
+                        hz /= DIGBEEP_HZ_STEP;
+                        hz++;
+                }
+                break;
+        default:
+                return -1;
+        }
+        beep->tone = hz;
+
+        /* schedule beep event */
+        schedule_work(&beep->beep_work);
+        return 0;
+}
+
+int snd_hda_attach_beep_device(struct hda_codec *codec, int nid)
+{
+        struct input_dev *input_dev;
+        struct hda_beep *beep;
+        int err;
+
+        beep = kzalloc(sizeof(*beep), GFP_KERNEL);
+        if (beep == NULL)
+                return -ENOMEM;
+        snprintf(beep->phys, sizeof(beep->phys),
+                "card%d/codec#%d/beep0", codec->bus->card->number, codec->addr);
+        input_dev = input_allocate_device();
+
+        /* setup digital beep device */
+        input_dev->name = "HDA Digital PCBeep";
+        input_dev->phys = beep->phys;
+        input_dev->id.bustype = BUS_PCI;
+
+        input_dev->id.vendor = codec->vendor_id >> 16;
+        input_dev->id.product = codec->vendor_id & 0xffff;
+        input_dev->id.version = 0x01;
+
+        input_dev->evbit[0] = BIT_MASK(EV_SND);
+        input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
+        input_dev->event = snd_hda_beep_event;
+        input_dev->dev.parent = &codec->bus->pci->dev;
+        input_set_drvdata(input_dev, beep);
+
+        err = input_register_device(input_dev);
+        if (err < 0) {
+                kfree(input_dev);
+                kfree(beep);
+                return err;
+        }
+
+        /* enable linear scale */
+        snd_hda_codec_write(codec, nid, 0,
+                AC_VERB_SET_DIGI_CONVERT_2, 0x01);
+
+        beep->nid = nid;
+        beep->dev = input_dev;
+        beep->codec = codec;
+        codec->beep = beep;
+
+        INIT_WORK(&beep->beep_work, &snd_hda_generate_beep);
+        return 0;
+}
+
+void snd_hda_detach_beep_device(struct hda_codec *codec)
+{
+        struct hda_beep *beep = codec->beep;
+        if (beep) {
+                cancel_work_sync(&beep->beep_work);
+                flush_scheduled_work();
+
+                input_unregister_device(beep->dev);
+                kfree(beep);
+        }
+}