LXR linux/sound/pci/hda/hda

   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
  30enum {
  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
  36static 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 */
  57static 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 */
  81static 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
  93static 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
 117static 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
 127static 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
 164static 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
 175static 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
 186int 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}
 212EXPORT_SYMBOL_HDA(snd_hda_enable_beep_device);
 213
 214int 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}
 253EXPORT_SYMBOL_HDA(snd_hda_attach_beep_device);
 254
 255void 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}
 267EXPORT_SYMBOL_HDA(snd_hda_detach_beep_device);
 268