xref: /linux/sound/pci/hda/hda_beep.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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);
269