sound/pci/hda/hda_beep.c

   1 /*
   2  * Digital Beep Input Interface for HD-audio codec
   3  *
   4  * Author: Matthew Ranostay <mranostay@embeddedalley.com>
   5  * Copyright (c) 2008 Embedded Alley Solutions Inc
   6  *
   7  *  This driver is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This driver is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  */
  21
  22 #include <linux/input.h>
  23 #include <linux/pci.h>
  24 #include <linux/workqueue.h>
  25 #include <sound/core.h>
  26 #include "hda_beep.h"
  27
  28 enum {
  29         DIGBEEP_HZ_STEP = 46875,        /* 46.875 Hz */
  30         DIGBEEP_HZ_MIN = 93750,         /* 93.750 Hz */
  31         DIGBEEP_HZ_MAX = 12000000,      /* 12 KHz */
  32 };
  33
  34 static void snd_hda_generate_beep(struct work_struct *work)
  35 {
  36         struct hda_beep *beep =
  37                 container_of(work, struct hda_beep, beep_work);
  38         struct hda_codec *codec = beep->codec;
  39
  40         if (!beep->enabled)
  41                 return;
  42
  43         /* generate tone */
  44         snd_hda_codec_write_cache(codec, beep->nid, 0,
  45                         AC_VERB_SET_BEEP_CONTROL, beep->tone);
  46 }
  47
  48 static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
  49                                 unsigned int code, int hz)
  50 {
  51         struct hda_beep *beep = input_get_drvdata(dev);
  52
  53         switch (code) {
  54         case SND_BELL:
  55                 if (hz)
  56                         hz = 1000;
  57         case SND_TONE:
  58                 hz *= 1000; /* fixed point */
  59                 hz = hz - DIGBEEP_HZ_MIN;
  60                 if (hz < 0)
  61                         hz = 0; /* turn off PC beep*/
  62                 else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN))
  63                         hz = 0xff;
  64                 else {
  65                         hz /= DIGBEEP_HZ_STEP;
  66                         hz++;
  67                 }
  68                 break;
  69         default:
  70                 return -1;
  71         }
  72         beep->tone = hz;
  73
  74         /* schedule beep event */
  75         schedule_work(&beep->beep_work);
  76         return 0;
  77 }
  78
  79 int snd_hda_attach_beep_device(struct hda_codec *codec, int nid)
  80 {
  81         struct input_dev *input_dev;
  82         struct hda_beep *beep;
  83         int err;
  84
  85         beep = kzalloc(sizeof(*beep), GFP_KERNEL);
  86         if (beep == NULL)
  87                 return -ENOMEM;
  88         snprintf(beep->phys, sizeof(beep->phys),
  89                 "card%d/codec#%d/beep0", codec->bus->card->number, codec->addr);
  90         input_dev = input_allocate_device();
  91         if (!input_dev) {
  92                 kfree(beep);
  93                 return -ENOMEM;
  94         }
  95
  96         /* setup digital beep device */
  97         input_dev->name = "HDA Digital PCBeep";
  98         input_dev->phys = beep->phys;
  99         input_dev->id.bustype = BUS_PCI;
 100
 101         input_dev->id.vendor = codec->vendor_id >> 16;
 102         input_dev->id.product = codec->vendor_id & 0xffff;
 103         input_dev->id.version = 0x01;
 104
 105         input_dev->evbit[0] = BIT_MASK(EV_SND);
 106         input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
 107         input_dev->event = snd_hda_beep_event;
 108         input_dev->dev.parent = &codec->bus->pci->dev;
 109         input_set_drvdata(input_dev, beep);
 110
 111         err = input_register_device(input_dev);
 112         if (err < 0) {
 113                 input_free_device(input_dev);
 114                 kfree(beep);
 115                 return err;
 116         }
 117
 118         /* enable linear scale */
 119         snd_hda_codec_write(codec, nid, 0,
 120                 AC_VERB_SET_DIGI_CONVERT_2, 0x01);
 121
 122         beep->nid = nid;
 123         beep->dev = input_dev;
 124         beep->codec = codec;
 125         beep->enabled = 1;
 126         codec->beep = beep;
 127
 128         INIT_WORK(&beep->beep_work, &snd_hda_generate_beep);
 129         return 0;
 130 }
 131
 132 void snd_hda_detach_beep_device(struct hda_codec *codec)
 133 {
 134         struct hda_beep *beep = codec->beep;
 135         if (beep) {
 136                 cancel_work_sync(&beep->beep_work);
 137                 flush_scheduled_work();
 138
 139                 input_unregister_device(beep->dev);
 140                 kfree(beep);
 141         }
 142 }