2 * Digital Beep Input Interface for HD-audio codec
4 * Author: Matthew Ranostay <mranostay@embeddedalley.com>
5 * Copyright (c) 2008 Embedded Alley Solutions Inc
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.
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.
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
22 #include <linux/input.h>
23 #include <linux/pci.h>
24 #include <linux/workqueue.h>
25 #include <sound/core.h>
29 DIGBEEP_HZ_STEP = 46875, /* 46.875 Hz */
30 DIGBEEP_HZ_MIN = 93750, /* 93.750 Hz */
31 DIGBEEP_HZ_MAX = 12000000, /* 12 KHz */
34 static void snd_hda_generate_beep(struct work_struct *work)
36 struct hda_beep *beep =
37 container_of(work, struct hda_beep, beep_work);
38 struct hda_codec *codec = beep->codec;
44 snd_hda_codec_write_cache(codec, beep->nid, 0,
45 AC_VERB_SET_BEEP_CONTROL, beep->tone);
48 /* (non-standard) Linear beep tone calculation for IDT/STAC codecs
50 * The tone frequency of beep generator on IDT/STAC codecs is
51 * defined from the 8bit tone parameter, in Hz,
52 * freq = 48000 * (257 - tone) / 1024
53 * that is from 12kHz to 93.75kHz in step of 46.875 hz
55 static int beep_linear_tone(struct hda_beep *beep, int hz)
57 hz *= 1000; /* fixed point */
58 hz = hz - DIGBEEP_HZ_MIN;
60 hz = 0; /* turn off PC beep*/
61 else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN))
64 hz /= DIGBEEP_HZ_STEP;
70 /* HD-audio standard beep tone parameter calculation
72 * The tone frequency in Hz is calculated as
73 * freq = 48000 / (tone * 4)
76 static int beep_standard_tone(struct hda_beep *beep, int hz)
79 return 0; /* disabled */
88 static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
89 unsigned int code, int hz)
91 struct hda_beep *beep = input_get_drvdata(dev);
98 if (beep->linear_tone)
99 beep->tone = beep_linear_tone(beep, hz);
101 beep->tone = beep_standard_tone(beep, hz);
107 /* schedule beep event */
108 schedule_work(&beep->beep_work);
112 int snd_hda_attach_beep_device(struct hda_codec *codec, int nid)
114 struct input_dev *input_dev;
115 struct hda_beep *beep;
118 beep = kzalloc(sizeof(*beep), GFP_KERNEL);
121 snprintf(beep->phys, sizeof(beep->phys),
122 "card%d/codec#%d/beep0", codec->bus->card->number, codec->addr);
123 input_dev = input_allocate_device();
129 /* setup digital beep device */
130 input_dev->name = "HDA Digital PCBeep";
131 input_dev->phys = beep->phys;
132 input_dev->id.bustype = BUS_PCI;
134 input_dev->id.vendor = codec->vendor_id >> 16;
135 input_dev->id.product = codec->vendor_id & 0xffff;
136 input_dev->id.version = 0x01;
138 input_dev->evbit[0] = BIT_MASK(EV_SND);
139 input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
140 input_dev->event = snd_hda_beep_event;
141 input_dev->dev.parent = &codec->bus->pci->dev;
142 input_set_drvdata(input_dev, beep);
144 err = input_register_device(input_dev);
146 input_free_device(input_dev);
151 /* enable linear scale */
152 snd_hda_codec_write(codec, nid, 0,
153 AC_VERB_SET_DIGI_CONVERT_2, 0x01);
156 beep->dev = input_dev;
161 INIT_WORK(&beep->beep_work, &snd_hda_generate_beep);
164 EXPORT_SYMBOL_HDA(snd_hda_attach_beep_device);
166 void snd_hda_detach_beep_device(struct hda_codec *codec)
168 struct hda_beep *beep = codec->beep;
170 cancel_work_sync(&beep->beep_work);
172 input_unregister_device(beep->dev);
177 EXPORT_SYMBOL_HDA(snd_hda_detach_beep_device);