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