pcsp.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * PC-Speaker driver for Linux
  4 *
  5 * Copyright (C) 1997-2001  David Woodhouse
  6 * Copyright (C) 2001-2008  Stas Sergeev
  7 */
  8
  9#include <linux/init.h>
 10#include <linux/module.h>
 11#include <linux/platform_device.h>
 12#include <sound/core.h>
 13#include <sound/initval.h>
 14#include <sound/pcm.h>
 15#include <linux/input.h>
 16#include <linux/delay.h>
 17#include <linux/bitops.h>
 18#include <linux/mm.h>
 19#include "pcsp_input.h"
 20#include "pcsp.h"
 21
 22MODULE_AUTHOR("Stas Sergeev <stsp@users.sourceforge.net>");
 23MODULE_DESCRIPTION("PC-Speaker driver");
 24MODULE_LICENSE("GPL");
 25MODULE_ALIAS("platform:pcspkr");
 26
 27static int index = SNDRV_DEFAULT_IDX1;	/* Index 0-MAX */
 28static char *id = SNDRV_DEFAULT_STR1;	/* ID for this card */
 29static bool enable = SNDRV_DEFAULT_ENABLE1;	/* Enable this card */
 30static bool nopcm;	/* Disable PCM capability of the driver */
 31
 32module_param(index, int, 0444);
 33MODULE_PARM_DESC(index, "Index value for pcsp soundcard.");
 34module_param(id, charp, 0444);
 35MODULE_PARM_DESC(id, "ID string for pcsp soundcard.");
 36module_param(enable, bool, 0444);
 37MODULE_PARM_DESC(enable, "Enable PC-Speaker sound.");
 38module_param(nopcm, bool, 0444);
 39MODULE_PARM_DESC(nopcm, "Disable PC-Speaker PCM sound. Only beeps remain.");
 40
 41struct snd_pcsp pcsp_chip;
 42
 43static int snd_pcsp_create(struct snd_card *card)
 44{
 45	unsigned int resolution = hrtimer_resolution;
 46	int div, min_div, order;
 47
 48	if (!nopcm) {
 49		if (resolution > PCSP_MAX_PERIOD_NS) {
 50			dev_err(card->dev,
 51				"PCSP: Timer resolution is not sufficient (%unS)\n",
 52				resolution);
 53			dev_err(card->dev,
 54				"PCSP: Make sure you have HPET and ACPI enabled.\n");
 55			dev_err(card->dev, "PCSP: Turned into nopcm mode.\n");
 56			nopcm = 1;
 57		}
 58	}
 59
 60	if (loops_per_jiffy >= PCSP_MIN_LPJ && resolution <= PCSP_MIN_PERIOD_NS)
 61		min_div = MIN_DIV;
 62	else
 63		min_div = MAX_DIV;
 64#if PCSP_DEBUG
 65	dev_dbg(card->dev, "PCSP: lpj=%li, min_div=%i, res=%u\n",
 66		loops_per_jiffy, min_div, resolution);
 67#endif
 68
 69	div = MAX_DIV / min_div;
 70	order = fls(div) - 1;
 71
 72	pcsp_chip.max_treble = min(order, PCSP_MAX_TREBLE);
 73	pcsp_chip.treble = min(pcsp_chip.max_treble, PCSP_DEFAULT_TREBLE);
 74	pcsp_chip.playback_ptr = 0;
 75	pcsp_chip.period_ptr = 0;
 76	atomic_set(&pcsp_chip.timer_active, 0);
 77	pcsp_chip.enable = 1;
 78	pcsp_chip.pcspkr = 1;
 79
 80	spin_lock_init(&pcsp_chip.substream_lock);
 81
 82	pcsp_chip.card = card;
 83	pcsp_chip.port = 0x61;
 84	pcsp_chip.irq = -1;
 85	pcsp_chip.dma = -1;
 86	card->private_data = &pcsp_chip;
 87
 88	return 0;
 89}
 90
 91static void pcsp_stop_beep(struct snd_pcsp *chip);
 92
 93static void alsa_card_pcsp_free(struct snd_card *card)
 94{
 95	pcsp_stop_beep(card->private_data);
 96}
 97
 98static int snd_card_pcsp_probe(int devnum, struct device *dev)
 99{
100	struct snd_card *card;
101	int err;
102
103	if (devnum != 0)
104		return -EINVAL;
105
106	hrtimer_setup(&pcsp_chip.timer, pcsp_do_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
107
108	err = snd_devm_card_new(dev, index, id, THIS_MODULE, 0, &card);
109	if (err < 0)
110		return err;
111
112	err = snd_pcsp_create(card);
113	if (err < 0)
114		return err;
115
116	if (!nopcm) {
117		err = snd_pcsp_new_pcm(&pcsp_chip);
118		if (err < 0)
119			return err;
120	}
121	err = snd_pcsp_new_mixer(&pcsp_chip, nopcm);
122	if (err < 0)
123		return err;
124
125	strscpy(card->driver, "PC-Speaker");
126	strscpy(card->shortname, "pcsp");
127	sprintf(card->longname, "Internal PC-Speaker at port 0x%x",
128		pcsp_chip.port);
129
130	err = snd_card_register(card);
131	if (err < 0)
132		return err;
133	card->private_free = alsa_card_pcsp_free;
134
135	return 0;
136}
137
138static int alsa_card_pcsp_init(struct device *dev)
139{
140	int err;
141
142	err = snd_card_pcsp_probe(0, dev);
143	if (err) {
144		dev_err(dev, "PC-Speaker initialization failed.\n");
145		return err;
146	}
147
148	/* Well, CONFIG_DEBUG_PAGEALLOC makes the sound horrible. Lets alert */
149	if (debug_pagealloc_enabled()) {
150		dev_warn(dev,
151			 "PCSP: CONFIG_DEBUG_PAGEALLOC is enabled, which may make the sound noisy.\n");
152	}
153
154	return 0;
155}
156
157static int pcsp_probe(struct platform_device *dev)
158{
159	int err;
160
161	err = pcspkr_input_init(&pcsp_chip.input_dev, &dev->dev);
162	if (err < 0)
163		return err;
164
165	err = alsa_card_pcsp_init(&dev->dev);
166	if (err < 0)
167		return err;
168
169	platform_set_drvdata(dev, &pcsp_chip);
170	return 0;
171}
172
173static void pcsp_stop_beep(struct snd_pcsp *chip)
174{
175	pcsp_sync_stop(chip);
176	pcspkr_stop_sound();
177}
178
179static int pcsp_suspend(struct device *dev)
180{
181	struct snd_pcsp *chip = dev_get_drvdata(dev);
182	pcsp_stop_beep(chip);
183	return 0;
184}
185
186static DEFINE_SIMPLE_DEV_PM_OPS(pcsp_pm, pcsp_suspend, NULL);
187
188static void pcsp_shutdown(struct platform_device *dev)
189{
190	struct snd_pcsp *chip = platform_get_drvdata(dev);
191	pcsp_stop_beep(chip);
192}
193
194static struct platform_driver pcsp_platform_driver = {
195	.driver		= {
196		.name	= "pcspkr",
197		.pm	= &pcsp_pm,
198	},
199	.probe		= pcsp_probe,
200	.shutdown	= pcsp_shutdown,
201};
202
203static int __init pcsp_init(void)
204{
205	if (!enable)
206		return -ENODEV;
207	return platform_driver_register(&pcsp_platform_driver);
208}
209
210static void __exit pcsp_exit(void)
211{
212	platform_driver_unregister(&pcsp_platform_driver);
213}
214
215module_init(pcsp_init);
216module_exit(pcsp_exit);