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 #include "hda_local.h" 28 29 enum { 30 DIGBEEP_HZ_STEP = 46875, /* 46.875 Hz */ 31 DIGBEEP_HZ_MIN = 93750, /* 93.750 Hz */ 32 DIGBEEP_HZ_MAX = 12000000, /* 12 KHz */ 33 }; 34 35 static void snd_hda_generate_beep(struct work_struct *work) 36 { 37 struct hda_beep *beep = 38 container_of(work, struct hda_beep, beep_work); 39 struct hda_codec *codec = beep->codec; 40 41 if (!beep->enabled) 42 return; 43 44 /* generate tone */ 45 snd_hda_codec_write_cache(codec, beep->nid, 0, 46 AC_VERB_SET_BEEP_CONTROL, beep->tone); 47 } 48 49 /* (non-standard) Linear beep tone calculation for IDT/STAC codecs 50 * 51 * The tone frequency of beep generator on IDT/STAC codecs is 52 * defined from the 8bit tone parameter, in Hz, 53 * freq = 48000 * (257 - tone) / 1024 54 * that is from 12kHz to 93.75Hz in steps of 46.875 Hz 55 */ 56 static int beep_linear_tone(struct hda_beep *beep, int hz) 57 { 58 if (hz <= 0) 59 return 0; 60 hz *= 1000; /* fixed point */ 61 hz = hz - DIGBEEP_HZ_MIN 62 + DIGBEEP_HZ_STEP / 2; /* round to nearest step */ 63 if (hz < 0) 64 hz = 0; /* turn off PC beep*/ 65 else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN)) 66 hz = 1; /* max frequency */ 67 else { 68 hz /= DIGBEEP_HZ_STEP; 69 hz = 255 - hz; 70 } 71 return hz; 72 } 73 74 /* HD-audio standard beep tone parameter calculation 75 * 76 * The tone frequency in Hz is calculated as 77 * freq = 48000 / (tone * 4) 78 * from 47Hz to 12kHz 79 */ 80 static int beep_standard_tone(struct hda_beep *beep, int hz) 81 { 82 if (hz <= 0) 83 return 0; /* disabled */ 84 hz = 12000 / hz; 85 if (hz > 0xff) 86 return 0xff; 87 if (hz <= 0) 88 return 1; 89 return hz; 90 } 91 92 static int snd_hda_beep_event(struct input_dev *dev, unsigned int type, 93 unsigned int code, int hz) 94 { 95 struct hda_beep *beep = input_get_drvdata(dev); 96 97 switch (code) { 98 case SND_BELL: 99 if (hz) 100 hz = 1000; 101 case SND_TONE: 102 if (beep->linear_tone) 103 beep->tone = beep_linear_tone(beep, hz); 104 else 105 beep->tone = beep_standard_tone(beep, hz); 106 break; 107 default: 108 return -1; 109 } 110 111 /* schedule beep event */ 112 schedule_work(&beep->beep_work); 113 return 0; 114 } 115 116 int snd_hda_attach_beep_device(struct hda_codec *codec, int nid) 117 { 118 struct input_dev *input_dev; 119 struct hda_beep *beep; 120 int err; 121 122 if (!snd_hda_get_bool_hint(codec, "beep")) 123 return 0; /* disabled explicitly */ 124 125 beep = kzalloc(sizeof(*beep), GFP_KERNEL); 126 if (beep == NULL) 127 return -ENOMEM; 128 snprintf(beep->phys, sizeof(beep->phys), 129 "card%d/codec#%d/beep0", codec->bus->card->number, codec->addr); 130 input_dev = input_allocate_device(); 131 if (!input_dev) { 132 kfree(beep); 133 return -ENOMEM; 134 } 135 136 /* setup digital beep device */ 137 input_dev->name = "HDA Digital PCBeep"; 138 input_dev->phys = beep->phys; 139 input_dev->id.bustype = BUS_PCI; 140 141 input_dev->id.vendor = codec->vendor_id >> 16; 142 input_dev->id.product = codec->vendor_id & 0xffff; 143 input_dev->id.version = 0x01; 144 145 input_dev->evbit[0] = BIT_MASK(EV_SND); 146 input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE); 147 input_dev->event = snd_hda_beep_event; 148 input_dev->dev.parent = &codec->bus->pci->dev; 149 input_set_drvdata(input_dev, beep); 150 151 err = input_register_device(input_dev); 152 if (err < 0) { 153 input_free_device(input_dev); 154 kfree(beep); 155 return err; 156 } 157 158 /* enable linear scale */ 159 snd_hda_codec_write(codec, nid, 0, 160 AC_VERB_SET_DIGI_CONVERT_2, 0x01); 161 162 beep->nid = nid; 163 beep->dev = input_dev; 164 beep->codec = codec; 165 beep->enabled = 1; 166 codec->beep = beep; 167 168 INIT_WORK(&beep->beep_work, &snd_hda_generate_beep); 169 return 0; 170 } 171 EXPORT_SYMBOL_HDA(snd_hda_attach_beep_device); 172 173 void snd_hda_detach_beep_device(struct hda_codec *codec) 174 { 175 struct hda_beep *beep = codec->beep; 176 if (beep) { 177 cancel_work_sync(&beep->beep_work); 178 179 input_unregister_device(beep->dev); 180 kfree(beep); 181 codec->beep = NULL; 182 } 183 } 184 EXPORT_SYMBOL_HDA(snd_hda_detach_beep_device); 185