kernel-fxtec-pro1x/sound/drivers/pcsp/pcsp.c
Peter Zijlstra ca109491f6 hrtimer: removing all ur callback modes
Impact: cleanup, move all hrtimer processing into hardirq context

This is an attempt at removing some of the hrtimer complexity by
reducing the number of callback modes to 1.

This means that all hrtimer callback functions will be ran from HARD-irq
context.

I went through all the 30 odd hrtimer callback functions in the kernel
and saw only one that I'm not quite sure of, which is the one in
net/can/bcm.c - hence I'm CC-ing the folks responsible for that code.

Furthermore, the hrtimer core now calls callbacks directly with IRQs
disabled in case you try to enqueue an expired timer. If this timer is a
periodic timer (which should use hrtimer_forward() to advance its time)
then it might be possible to end up in an inf. recursive loop due to the
fact that hrtimer_forward() doesn't round up to the next timer
granularity, and therefore keeps on calling the callback - obviously
this needs a fix.

Aside from that, this seems to compile and actually boot on my dual core
test box - although I'm sure there are some bugs in, me not hitting any
makes me certain :-)

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-25 15:45:46 +01:00

238 lines
5.3 KiB
C

/*
* PC-Speaker driver for Linux
*
* Copyright (C) 1997-2001 David Woodhouse
* Copyright (C) 2001-2008 Stas Sergeev
*/
#include <linux/init.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <asm/bitops.h>
#include "pcsp_input.h"
#include "pcsp.h"
MODULE_AUTHOR("Stas Sergeev <stsp@users.sourceforge.net>");
MODULE_DESCRIPTION("PC-Speaker driver");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{PC-Speaker, pcsp}}");
MODULE_ALIAS("platform:pcspkr");
static int index = SNDRV_DEFAULT_IDX1; /* Index 0-MAX */
static char *id = SNDRV_DEFAULT_STR1; /* ID for this card */
static int enable = SNDRV_DEFAULT_ENABLE1; /* Enable this card */
module_param(index, int, 0444);
MODULE_PARM_DESC(index, "Index value for pcsp soundcard.");
module_param(id, charp, 0444);
MODULE_PARM_DESC(id, "ID string for pcsp soundcard.");
module_param(enable, bool, 0444);
MODULE_PARM_DESC(enable, "Enable PC-Speaker sound.");
struct snd_pcsp pcsp_chip;
static int __devinit snd_pcsp_create(struct snd_card *card)
{
static struct snd_device_ops ops = { };
struct timespec tp;
int err;
int div, min_div, order;
hrtimer_get_res(CLOCK_MONOTONIC, &tp);
if (tp.tv_sec || tp.tv_nsec > PCSP_MAX_PERIOD_NS) {
printk(KERN_ERR "PCSP: Timer resolution is not sufficient "
"(%linS)\n", tp.tv_nsec);
printk(KERN_ERR "PCSP: Make sure you have HPET and ACPI "
"enabled.\n");
return -EIO;
}
if (loops_per_jiffy >= PCSP_MIN_LPJ && tp.tv_nsec <= PCSP_MIN_PERIOD_NS)
min_div = MIN_DIV;
else
min_div = MAX_DIV;
#if PCSP_DEBUG
printk("PCSP: lpj=%li, min_div=%i, res=%li\n",
loops_per_jiffy, min_div, tp.tv_nsec);
#endif
div = MAX_DIV / min_div;
order = fls(div) - 1;
pcsp_chip.max_treble = min(order, PCSP_MAX_TREBLE);
pcsp_chip.treble = min(pcsp_chip.max_treble, PCSP_DEFAULT_TREBLE);
pcsp_chip.playback_ptr = 0;
pcsp_chip.period_ptr = 0;
atomic_set(&pcsp_chip.timer_active, 0);
pcsp_chip.enable = 1;
pcsp_chip.pcspkr = 1;
spin_lock_init(&pcsp_chip.substream_lock);
pcsp_chip.card = card;
pcsp_chip.port = 0x61;
pcsp_chip.irq = -1;
pcsp_chip.dma = -1;
/* Register device */
err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, &pcsp_chip, &ops);
if (err < 0)
return err;
return 0;
}
static int __devinit snd_card_pcsp_probe(int devnum, struct device *dev)
{
struct snd_card *card;
int err;
if (devnum != 0)
return -EINVAL;
hrtimer_init(&pcsp_chip.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
pcsp_chip.timer.function = pcsp_do_timer;
card = snd_card_new(index, id, THIS_MODULE, 0);
if (!card)
return -ENOMEM;
err = snd_pcsp_create(card);
if (err < 0) {
snd_card_free(card);
return err;
}
err = snd_pcsp_new_pcm(&pcsp_chip);
if (err < 0) {
snd_card_free(card);
return err;
}
err = snd_pcsp_new_mixer(&pcsp_chip);
if (err < 0) {
snd_card_free(card);
return err;
}
snd_card_set_dev(pcsp_chip.card, dev);
strcpy(card->driver, "PC-Speaker");
strcpy(card->shortname, "pcsp");
sprintf(card->longname, "Internal PC-Speaker at port 0x%x",
pcsp_chip.port);
err = snd_card_register(card);
if (err < 0) {
snd_card_free(card);
return err;
}
return 0;
}
static int __devinit alsa_card_pcsp_init(struct device *dev)
{
int err;
err = snd_card_pcsp_probe(0, dev);
if (err) {
printk(KERN_ERR "PC-Speaker initialization failed.\n");
return err;
}
#ifdef CONFIG_DEBUG_PAGEALLOC
/* Well, CONFIG_DEBUG_PAGEALLOC makes the sound horrible. Lets alert */
printk(KERN_WARNING "PCSP: CONFIG_DEBUG_PAGEALLOC is enabled, "
"which may make the sound noisy.\n");
#endif
return 0;
}
static void __devexit alsa_card_pcsp_exit(struct snd_pcsp *chip)
{
snd_card_free(chip->card);
}
static int __devinit pcsp_probe(struct platform_device *dev)
{
int err;
err = pcspkr_input_init(&pcsp_chip.input_dev, &dev->dev);
if (err < 0)
return err;
err = alsa_card_pcsp_init(&dev->dev);
if (err < 0) {
pcspkr_input_remove(pcsp_chip.input_dev);
return err;
}
platform_set_drvdata(dev, &pcsp_chip);
return 0;
}
static int __devexit pcsp_remove(struct platform_device *dev)
{
struct snd_pcsp *chip = platform_get_drvdata(dev);
alsa_card_pcsp_exit(chip);
pcspkr_input_remove(chip->input_dev);
platform_set_drvdata(dev, NULL);
return 0;
}
static void pcsp_stop_beep(struct snd_pcsp *chip)
{
spin_lock_irq(&chip->substream_lock);
if (!chip->playback_substream)
pcspkr_stop_sound();
spin_unlock_irq(&chip->substream_lock);
}
#ifdef CONFIG_PM
static int pcsp_suspend(struct platform_device *dev, pm_message_t state)
{
struct snd_pcsp *chip = platform_get_drvdata(dev);
pcsp_stop_beep(chip);
snd_pcm_suspend_all(chip->pcm);
return 0;
}
#else
#define pcsp_suspend NULL
#endif /* CONFIG_PM */
static void pcsp_shutdown(struct platform_device *dev)
{
struct snd_pcsp *chip = platform_get_drvdata(dev);
pcsp_stop_beep(chip);
}
static struct platform_driver pcsp_platform_driver = {
.driver = {
.name = "pcspkr",
.owner = THIS_MODULE,
},
.probe = pcsp_probe,
.remove = __devexit_p(pcsp_remove),
.suspend = pcsp_suspend,
.shutdown = pcsp_shutdown,
};
static int __init pcsp_init(void)
{
if (!enable)
return -ENODEV;
return platform_driver_register(&pcsp_platform_driver);
}
static void __exit pcsp_exit(void)
{
platform_driver_unregister(&pcsp_platform_driver);
}
module_init(pcsp_init);
module_exit(pcsp_exit);