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 
22 MODULE_AUTHOR("Stas Sergeev <stsp@users.sourceforge.net>");
23 MODULE_DESCRIPTION("PC-Speaker driver");
24 MODULE_LICENSE("GPL");
25 MODULE_ALIAS("platform:pcspkr");
26 
27 static int index = SNDRV_DEFAULT_IDX1;	/* Index 0-MAX */
28 static char *id = SNDRV_DEFAULT_STR1;	/* ID for this card */
29 static bool enable = SNDRV_DEFAULT_ENABLE1;	/* Enable this card */
30 static bool nopcm;	/* Disable PCM capability of the driver */
31 
32 module_param(index, int, 0444);
33 MODULE_PARM_DESC(index, "Index value for pcsp soundcard.");
34 module_param(id, charp, 0444);
35 MODULE_PARM_DESC(id, "ID string for pcsp soundcard.");
36 module_param(enable, bool, 0444);
37 MODULE_PARM_DESC(enable, "Enable PC-Speaker sound.");
38 module_param(nopcm, bool, 0444);
39 MODULE_PARM_DESC(nopcm, "Disable PC-Speaker PCM sound. Only beeps remain.");
40 
41 struct snd_pcsp pcsp_chip;
42 
snd_pcsp_create(struct snd_card * card)43 static 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 			printk(KERN_ERR "PCSP: Timer resolution is not sufficient "
51 				"(%unS)\n", resolution);
52 			printk(KERN_ERR "PCSP: Make sure you have HPET and ACPI "
53 				"enabled.\n");
54 			printk(KERN_ERR "PCSP: Turned into nopcm mode.\n");
55 			nopcm = 1;
56 		}
57 	}
58 
59 	if (loops_per_jiffy >= PCSP_MIN_LPJ && resolution <= PCSP_MIN_PERIOD_NS)
60 		min_div = MIN_DIV;
61 	else
62 		min_div = MAX_DIV;
63 #if PCSP_DEBUG
64 	printk(KERN_DEBUG "PCSP: lpj=%li, min_div=%i, res=%u\n",
65 	       loops_per_jiffy, min_div, resolution);
66 #endif
67 
68 	div = MAX_DIV / min_div;
69 	order = fls(div) - 1;
70 
71 	pcsp_chip.max_treble = min(order, PCSP_MAX_TREBLE);
72 	pcsp_chip.treble = min(pcsp_chip.max_treble, PCSP_DEFAULT_TREBLE);
73 	pcsp_chip.playback_ptr = 0;
74 	pcsp_chip.period_ptr = 0;
75 	atomic_set(&pcsp_chip.timer_active, 0);
76 	pcsp_chip.enable = 1;
77 	pcsp_chip.pcspkr = 1;
78 
79 	spin_lock_init(&pcsp_chip.substream_lock);
80 
81 	pcsp_chip.card = card;
82 	pcsp_chip.port = 0x61;
83 	pcsp_chip.irq = -1;
84 	pcsp_chip.dma = -1;
85 	card->private_data = &pcsp_chip;
86 
87 	return 0;
88 }
89 
90 static void pcsp_stop_beep(struct snd_pcsp *chip);
91 
alsa_card_pcsp_free(struct snd_card * card)92 static void alsa_card_pcsp_free(struct snd_card *card)
93 {
94 	pcsp_stop_beep(card->private_data);
95 }
96 
snd_card_pcsp_probe(int devnum,struct device * dev)97 static int snd_card_pcsp_probe(int devnum, struct device *dev)
98 {
99 	struct snd_card *card;
100 	int err;
101 
102 	if (devnum != 0)
103 		return -EINVAL;
104 
105 	hrtimer_init(&pcsp_chip.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
106 	pcsp_chip.timer.function = pcsp_do_timer;
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 	strcpy(card->driver, "PC-Speaker");
126 	strcpy(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 
alsa_card_pcsp_init(struct device * dev)138 static 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 		printk(KERN_ERR "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 		printk(KERN_WARNING "PCSP: CONFIG_DEBUG_PAGEALLOC is enabled, "
151 		       "which may make the sound noisy.\n");
152 	}
153 
154 	return 0;
155 }
156 
pcsp_probe(struct platform_device * dev)157 static 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 
pcsp_stop_beep(struct snd_pcsp * chip)173 static void pcsp_stop_beep(struct snd_pcsp *chip)
174 {
175 	pcsp_sync_stop(chip);
176 	pcspkr_stop_sound();
177 }
178 
179 #ifdef CONFIG_PM_SLEEP
pcsp_suspend(struct device * dev)180 static int pcsp_suspend(struct device *dev)
181 {
182 	struct snd_pcsp *chip = dev_get_drvdata(dev);
183 	pcsp_stop_beep(chip);
184 	return 0;
185 }
186 
187 static SIMPLE_DEV_PM_OPS(pcsp_pm, pcsp_suspend, NULL);
188 #define PCSP_PM_OPS	&pcsp_pm
189 #else
190 #define PCSP_PM_OPS	NULL
191 #endif	/* CONFIG_PM_SLEEP */
192 
pcsp_shutdown(struct platform_device * dev)193 static void pcsp_shutdown(struct platform_device *dev)
194 {
195 	struct snd_pcsp *chip = platform_get_drvdata(dev);
196 	pcsp_stop_beep(chip);
197 }
198 
199 static struct platform_driver pcsp_platform_driver = {
200 	.driver		= {
201 		.name	= "pcspkr",
202 		.pm	= PCSP_PM_OPS,
203 	},
204 	.probe		= pcsp_probe,
205 	.shutdown	= pcsp_shutdown,
206 };
207 
pcsp_init(void)208 static int __init pcsp_init(void)
209 {
210 	if (!enable)
211 		return -ENODEV;
212 	return platform_driver_register(&pcsp_platform_driver);
213 }
214 
pcsp_exit(void)215 static void __exit pcsp_exit(void)
216 {
217 	platform_driver_unregister(&pcsp_platform_driver);
218 }
219 
220 module_init(pcsp_init);
221 module_exit(pcsp_exit);
222