satip-axe/kernel/sound/pci/hda/hda_beep.c
2015-03-26 17:24:57 +01:00

185 lines
4.6 KiB
C

/*
* 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"
#include "hda_local.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;
if (!beep->enabled)
return;
/* generate tone */
snd_hda_codec_write_cache(codec, beep->nid, 0,
AC_VERB_SET_BEEP_CONTROL, beep->tone);
}
/* (non-standard) Linear beep tone calculation for IDT/STAC codecs
*
* The tone frequency of beep generator on IDT/STAC codecs is
* defined from the 8bit tone parameter, in Hz,
* freq = 48000 * (257 - tone) / 1024
* that is from 12kHz to 93.75Hz in steps of 46.875 Hz
*/
static int beep_linear_tone(struct hda_beep *beep, int hz)
{
if (hz <= 0)
return 0;
hz *= 1000; /* fixed point */
hz = hz - DIGBEEP_HZ_MIN
+ DIGBEEP_HZ_STEP / 2; /* round to nearest step */
if (hz < 0)
hz = 0; /* turn off PC beep*/
else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN))
hz = 1; /* max frequency */
else {
hz /= DIGBEEP_HZ_STEP;
hz = 255 - hz;
}
return hz;
}
/* HD-audio standard beep tone parameter calculation
*
* The tone frequency in Hz is calculated as
* freq = 48000 / (tone * 4)
* from 47Hz to 12kHz
*/
static int beep_standard_tone(struct hda_beep *beep, int hz)
{
if (hz <= 0)
return 0; /* disabled */
hz = 12000 / hz;
if (hz > 0xff)
return 0xff;
if (hz <= 0)
return 1;
return hz;
}
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:
if (beep->linear_tone)
beep->tone = beep_linear_tone(beep, hz);
else
beep->tone = beep_standard_tone(beep, hz);
break;
default:
return -1;
}
/* 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;
if (!snd_hda_get_bool_hint(codec, "beep"))
return 0; /* disabled explicitly */
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();
if (!input_dev) {
kfree(beep);
return -ENOMEM;
}
/* 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) {
input_free_device(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;
beep->enabled = 1;
codec->beep = beep;
INIT_WORK(&beep->beep_work, &snd_hda_generate_beep);
return 0;
}
EXPORT_SYMBOL_HDA(snd_hda_attach_beep_device);
void snd_hda_detach_beep_device(struct hda_codec *codec)
{
struct hda_beep *beep = codec->beep;
if (beep) {
cancel_work_sync(&beep->beep_work);
input_unregister_device(beep->dev);
kfree(beep);
codec->beep = NULL;
}
}
EXPORT_SYMBOL_HDA(snd_hda_detach_beep_device);