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/slab.h>
  25 #include <linux/workqueue.h>
  26 #include <sound/core.h>
  27 #include "hda_beep.h"
  28 #include "hda_local.h"
  29
  30 enum {
  31         DIGBEEP_HZ_STEP = 46875,        /* 46.875 Hz */
  32         DIGBEEP_HZ_MIN = 93750,         /* 93.750 Hz */
  33         DIGBEEP_HZ_MAX = 12000000,      /* 12 KHz */
  34 };
  35
  36 static void snd_hda_generate_beep(struct work_struct *work)
  37 {
  38         struct hda_beep *beep =
  39                 container_of(work, struct hda_beep, beep_work);
  40         struct hda_codec *codec = beep->codec;
  41
  42         if (!beep->enabled)
  43                 return;
  44
  45         /* generate tone */
  46         snd_hda_codec_write(codec, beep->nid, 0,
  47                         AC_VERB_SET_BEEP_CONTROL, beep->tone);
  48 }
  49
  50 /* (non-standard) Linear beep tone calculation for IDT/STAC codecs
  51  *
  52  * The tone frequency of beep generator on IDT/STAC codecs is
  53  * defined from the 8bit tone parameter, in Hz,
  54  *    freq = 48000 * (257 - tone) / 1024
  55  * that is from 12kHz to 93.75Hz in steps of 46.875 Hz
  56  */
  57 static int beep_linear_tone(struct hda_beep *beep, int hz)
  58 {
  59         if (hz <= 0)
  60                 return 0;
  61         hz *= 1000; /* fixed point */
  62         hz = hz - DIGBEEP_HZ_MIN
  63                 + DIGBEEP_HZ_STEP / 2; /* round to nearest step */
  64         if (hz < 0)
  65                 hz = 0; /* turn off PC beep*/
  66         else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN))
  67                 hz = 1; /* max frequency */
  68         else {
  69                 hz /= DIGBEEP_HZ_STEP;
  70                 hz = 255 - hz;
  71         }
  72         return hz;
  73 }
  74
  75 /* HD-audio standard beep tone parameter calculation
  76  *
  77  * The tone frequency in Hz is calculated as
  78  *   freq = 48000 / (tone * 4)
  79  * from 47Hz to 12kHz
  80  */
  81 static int beep_standard_tone(struct hda_beep *beep, int hz)
  82 {
  83         if (hz <= 0)
  84                 return 0; /* disabled */
  85         hz = 12000 / hz;
  86         if (hz > 0xff)
  87                 return 0xff;
  88         if (hz <= 0)
  89                 return 1;
  90         return hz;
  91 }
  92
  93 static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
  94                                 unsigned int code, int hz)
  95 {
  96         struct hda_beep *beep = input_get_drvdata(dev);
  97
  98         switch (code) {
  99         case SND_BELL:
 100                 if (hz)
 101                         hz = 1000;
 102         case SND_TONE:
 103                 if (beep->linear_tone)
 104                         beep->tone = beep_linear_tone(beep, hz);
 105                 else
 106                         beep->tone = beep_standard_tone(beep, hz);
 107                 break;
 108         default:
 109                 return -1;
 110         }
 111
 112         /* schedule beep event */
 113         schedule_work(&beep->beep_work);
 114         return 0;
 115 }
 116
 117 static void snd_hda_do_detach(struct hda_beep *beep)
 118 {
 119         input_unregister_device(beep->dev);
 120         beep->dev = NULL;
 121         cancel_work_sync(&beep->beep_work);
 122         /* turn off beep for sure */
 123         snd_hda_codec_write(beep->codec, beep->nid, 0,
 124                                   AC_VERB_SET_BEEP_CONTROL, 0);
 125 }
 126
 127 static int snd_hda_do_attach(struct hda_beep *beep)
 128 {
 129         struct input_dev *input_dev;
 130         struct hda_codec *codec = beep->codec;
 131         int err;
 132
 133         input_dev = input_allocate_device();
 134         if (!input_dev) {
 135                 printk(KERN_INFO "hda_beep: unable to allocate input device\n");
 136                 return -ENOMEM;
 137         }
 138
 139         /* setup digital beep device */
 140         input_dev->name = "HDA Digital PCBeep";
 141         input_dev->phys = beep->phys;
 142         input_dev->id.bustype = BUS_PCI;
 143
 144         input_dev->id.vendor = codec->vendor_id >> 16;
 145         input_dev->id.product = codec->vendor_id & 0xffff;
 146         input_dev->id.version = 0x01;
 147
 148         input_dev->evbit[0] = BIT_MASK(EV_SND);
 149         input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
 150         input_dev->event = snd_hda_beep_event;
 151         input_dev->dev.parent = &codec->bus->pci->dev;
 152         input_set_drvdata(input_dev, beep);
 153
 154         err = input_register_device(input_dev);
 155         if (err < 0) {
 156                 input_free_device(input_dev);
 157                 printk(KERN_INFO "hda_beep: unable to register input device\n");
 158                 return err;
 159         }
 160         beep->dev = input_dev;
 161         return 0;
 162 }
 163
 164 static void snd_hda_do_register(struct work_struct *work)
 165 {
 166         struct hda_beep *beep =
 167                 container_of(work, struct hda_beep, register_work);
 168
 169         mutex_lock(&beep->mutex);
 170         if (beep->enabled && !beep->dev)
 171                 snd_hda_do_attach(beep);
 172         mutex_unlock(&beep->mutex);
 173 }
 174
 175 static void snd_hda_do_unregister(struct work_struct *work)
 176 {
 177         struct hda_beep *beep =
 178                 container_of(work, struct hda_beep, unregister_work.work);
 179
 180         mutex_lock(&beep->mutex);
 181         if (!beep->enabled && beep->dev)
 182                 snd_hda_do_detach(beep);
 183         mutex_unlock(&beep->mutex);
 184 }
 185
 186 int snd_hda_enable_beep_device(struct hda_codec *codec, int enable)
 187 {
 188         struct hda_beep *beep = codec->beep;
 189         enable = !!enable;
 190         if (beep == NULL)
 191                 return 0;
 192         if (beep->enabled != enable) {
 193                 beep->enabled = enable;
 194                 if (!enable) {
 195                         /* turn off beep */
 196                         snd_hda_codec_write(beep->codec, beep->nid, 0,
 197                                                   AC_VERB_SET_BEEP_CONTROL, 0);
 198                 }
 199                 if (beep->mode == HDA_BEEP_MODE_SWREG) {
 200                         if (enable) {
 201                                 cancel_delayed_work(&beep->unregister_work);
 202                                 schedule_work(&beep->register_work);
 203                         } else {
 204                                 schedule_delayed_work(&beep->unregister_work,
 205                                                                            HZ);
 206                         }
 207                 }
 208                 return 1;
 209         }
 210         return 0;
 211 }
 212 EXPORT_SYMBOL_HDA(snd_hda_enable_beep_device);
 213
 214 int snd_hda_attach_beep_device(struct hda_codec *codec, int nid)
 215 {
 216         struct hda_beep *beep;
 217
 218         if (!snd_hda_get_bool_hint(codec, "beep"))
 219                 return 0; /* disabled explicitly by hints */
 220         if (codec->beep_mode == HDA_BEEP_MODE_OFF)
 221                 return 0; /* disabled by module option */
 222
 223         beep = kzalloc(sizeof(*beep), GFP_KERNEL);
 224         if (beep == NULL)
 225                 return -ENOMEM;
 226         snprintf(beep->phys, sizeof(beep->phys),
 227                 "card%d/codec#%d/beep0", codec->bus->card->number, codec->addr);
 228         /* enable linear scale */
 229         snd_hda_codec_write(codec, nid, 0,
 230                 AC_VERB_SET_DIGI_CONVERT_2, 0x01);
 231
 232         beep->nid = nid;
 233         beep->codec = codec;
 234         beep->mode = codec->beep_mode;
 235         codec->beep = beep;
 236
 237         INIT_WORK(&beep->register_work, &snd_hda_do_register);
 238         INIT_DELAYED_WORK(&beep->unregister_work, &snd_hda_do_unregister);
 239         INIT_WORK(&beep->beep_work, &snd_hda_generate_beep);
 240         mutex_init(&beep->mutex);
 241
 242         if (beep->mode == HDA_BEEP_MODE_ON) {
 243                 int err = snd_hda_do_attach(beep);
 244                 if (err < 0) {
 245                         kfree(beep);
 246                         codec->beep = NULL;
 247                         return err;
 248                 }
 249         }
 250
 251         return 0;
 252 }
 253 EXPORT_SYMBOL_HDA(snd_hda_attach_beep_device);
 254
 255 void snd_hda_detach_beep_device(struct hda_codec *codec)
 256 {
 257         struct hda_beep *beep = codec->beep;
 258         if (beep) {
 259                 cancel_work_sync(&beep->register_work);
 260                 cancel_delayed_work(&beep->unregister_work);
 261                 if (beep->dev)
 262                         snd_hda_do_detach(beep);
 263                 codec->beep = NULL;
 264                 kfree(beep);
 265         }
 266 }
 267 EXPORT_SYMBOL_HDA(snd_hda_detach_beep_device);