Say Y here to use the HR-timer backend as the default sequencer
timer.
-config SND_RTCTIMER
- tristate "RTC Timer support"
- depends on RTC
- select SND_TIMER
- help
- Say Y here to enable RTC timer support for ALSA. ALSA uses
- the RTC timer as a precise timing source and maps the RTC
- timer to ALSA's timer interface. The ALSA sequencer code also
- can use this timing source.
-
- To compile this driver as a module, choose M here: the module
- will be called snd-rtctimer.
-
- Note that this option is exclusive with the new RTC drivers
- (CONFIG_RTC_CLASS) since this requires the old API.
-
-config SND_SEQ_RTCTIMER_DEFAULT
- bool "Use RTC as default sequencer timer"
- depends on SND_RTCTIMER && SND_SEQUENCER
- depends on !SND_SEQ_HRTIMER_DEFAULT
- default y
- help
- Say Y here to use the RTC timer as the default sequencer
- timer. This is strongly recommended because it ensures
- precise MIDI timing even when the system timer runs at less
- than 1000 Hz.
-
- If in doubt, say Y.
-
config SND_DYNAMIC_MINORS
bool "Dynamic device file minor numbers"
help
+++ /dev/null
-/*
- * RTC based high-frequency timer
- *
- * Copyright (C) 2000 Takashi Iwai
- * based on rtctimer.c by Steve Ratcliffe
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- */
-
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/log2.h>
-#include <sound/core.h>
-#include <sound/timer.h>
-
-#if IS_ENABLED(CONFIG_RTC)
-
-#include <linux/mc146818rtc.h>
-
-#define RTC_FREQ 1024 /* default frequency */
-#define NANO_SEC 1000000000L /* 10^9 in sec */
-
-/*
- * prototypes
- */
-static int rtctimer_open(struct snd_timer *t);
-static int rtctimer_close(struct snd_timer *t);
-static int rtctimer_start(struct snd_timer *t);
-static int rtctimer_stop(struct snd_timer *t);
-
-
-/*
- * The hardware dependent description for this timer.
- */
-static struct snd_timer_hardware rtc_hw = {
- .flags = SNDRV_TIMER_HW_AUTO |
- SNDRV_TIMER_HW_FIRST |
- SNDRV_TIMER_HW_TASKLET,
- .ticks = 100000000L, /* FIXME: XXX */
- .open = rtctimer_open,
- .close = rtctimer_close,
- .start = rtctimer_start,
- .stop = rtctimer_stop,
-};
-
-static int rtctimer_freq = RTC_FREQ; /* frequency */
-static struct snd_timer *rtctimer;
-static struct tasklet_struct rtc_tasklet;
-static rtc_task_t rtc_task;
-
-
-static int
-rtctimer_open(struct snd_timer *t)
-{
- int err;
-
- err = rtc_register(&rtc_task);
- if (err < 0)
- return err;
- t->private_data = &rtc_task;
- return 0;
-}
-
-static int
-rtctimer_close(struct snd_timer *t)
-{
- rtc_task_t *rtc = t->private_data;
- if (rtc) {
- rtc_unregister(rtc);
- tasklet_kill(&rtc_tasklet);
- t->private_data = NULL;
- }
- return 0;
-}
-
-static int
-rtctimer_start(struct snd_timer *timer)
-{
- rtc_task_t *rtc = timer->private_data;
- if (snd_BUG_ON(!rtc))
- return -EINVAL;
- rtc_control(rtc, RTC_IRQP_SET, rtctimer_freq);
- rtc_control(rtc, RTC_PIE_ON, 0);
- return 0;
-}
-
-static int
-rtctimer_stop(struct snd_timer *timer)
-{
- rtc_task_t *rtc = timer->private_data;
- if (snd_BUG_ON(!rtc))
- return -EINVAL;
- rtc_control(rtc, RTC_PIE_OFF, 0);
- return 0;
-}
-
-static void rtctimer_tasklet(unsigned long data)
-{
- snd_timer_interrupt((struct snd_timer *)data, 1);
-}
-
-/*
- * interrupt
- */
-static void rtctimer_interrupt(void *private_data)
-{
- tasklet_schedule(private_data);
-}
-
-
-/*
- * ENTRY functions
- */
-static int __init rtctimer_init(void)
-{
- int err;
- struct snd_timer *timer;
-
- if (rtctimer_freq < 2 || rtctimer_freq > 8192 ||
- !is_power_of_2(rtctimer_freq)) {
- pr_err("ALSA: rtctimer: invalid frequency %d\n", rtctimer_freq);
- return -EINVAL;
- }
-
- /* Create a new timer and set up the fields */
- err = snd_timer_global_new("rtc", SNDRV_TIMER_GLOBAL_RTC, &timer);
- if (err < 0)
- return err;
-
- timer->module = THIS_MODULE;
- strcpy(timer->name, "RTC timer");
- timer->hw = rtc_hw;
- timer->hw.resolution = NANO_SEC / rtctimer_freq;
-
- tasklet_init(&rtc_tasklet, rtctimer_tasklet, (unsigned long)timer);
-
- /* set up RTC callback */
- rtc_task.func = rtctimer_interrupt;
- rtc_task.private_data = &rtc_tasklet;
-
- err = snd_timer_global_register(timer);
- if (err < 0) {
- snd_timer_global_free(timer);
- return err;
- }
- rtctimer = timer; /* remember this */
-
- return 0;
-}
-
-static void __exit rtctimer_exit(void)
-{
- if (rtctimer) {
- snd_timer_global_free(rtctimer);
- rtctimer = NULL;
- }
-}
-
-
-/*
- * exported stuff
- */
-module_init(rtctimer_init)
-module_exit(rtctimer_exit)
-
-module_param(rtctimer_freq, int, 0444);
-MODULE_PARM_DESC(rtctimer_freq, "timer frequency in Hz");
-
-MODULE_LICENSE("GPL");
-
-MODULE_ALIAS("snd-timer-" __stringify(SNDRV_TIMER_GLOBAL_RTC));
-
-#endif /* IS_ENABLED(CONFIG_RTC) */
projects / karo-tx-linux.git / commitdiff