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//=========================================================
// MusE
// Linux Music Editor
// $Id: alsatimer.cpp,v 1.1.2.9 2009/03/28 01:46:10 terminator356 Exp $
//
// Plenty of code borrowed from timer.c example in
// alsalib 1.0.7
//
// (C) Copyright 2004 Robert Jonsson (rj@spamatica.se)
//
// 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; 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
//=========================================================
#include "alsatimer.h"
#include <climits>
#define TIMER_DEBUG 0
namespace MusECore {
AlsaTimer::AlsaTimer()
{
if(TIMER_DEBUG)
fprintf(stderr,"AlsaTimer::AlsaTimer(this=%p) called\n",this);
handle = NULL;
id = NULL;
info = NULL;
params = NULL;
findBest = true;
}
AlsaTimer::~AlsaTimer()
{
if(TIMER_DEBUG)
fprintf(stderr,"AlsaTimer::~AlsaTimer(this=%p) called\n",this);
if (handle)
snd_timer_close(handle);
if (id) snd_timer_id_free(id);
if (info) snd_timer_info_free(info);
if (params) snd_timer_params_free(params);
}
signed int AlsaTimer::initTimer()
{
if(TIMER_DEBUG)
printf("AlsaTimer::initTimer(this=%p)\n",this);
int err;
int devclass = SND_TIMER_CLASS_GLOBAL;
int sclass = SND_TIMER_CLASS_NONE;
int card = 0;
int device = SND_TIMER_GLOBAL_SYSTEM;
int subdevice = 0;
int test_ids[] = { SND_TIMER_GLOBAL_SYSTEM
, SND_TIMER_GLOBAL_RTC
#ifdef SND_TIMER_GLOBAL_HPET
, SND_TIMER_GLOBAL_HPET
#endif
};
int max_ids = sizeof(test_ids) / sizeof(int);
long best_res = LONG_MAX;
//int best_dev = -1; // SND_TIMER_GLOBAL_SYSTEM;
int best_dev = SND_TIMER_GLOBAL_SYSTEM;
int i;
if (id || info || params) {
fprintf(stderr,"AlsaTimer::initTimer(): called on initialised timer!\n");
return fds->fd;
}
snd_timer_id_malloc(&id);
snd_timer_info_malloc(&info);
snd_timer_params_malloc(¶ms);
if (findBest) {
for (i = 0; i < max_ids; ++i) {
device = test_ids[i];
sprintf(timername, "hw:CLASS=%i,SCLASS=%i,CARD=%i,DEV=%i,SUBDEV=%i", devclass, sclass, card, device, subdevice);
if ((err = snd_timer_open(&handle, timername, SND_TIMER_OPEN_NONBLOCK)) < 0) {
continue;
}
if ((err = snd_timer_info(handle, info)) < 0) {
snd_timer_close(handle);
continue;
}
// select a non slave timer with the lowest resolution value
int is_slave = snd_timer_info_is_slave(info);
long res = snd_timer_info_get_resolution(info);
if ((is_slave == 0) && (best_res > res)) {
best_res = res;
best_dev = device;
}
snd_timer_close(handle);
}
device = best_dev;
}
//if(best_dev==-1)
// return -1; // no working timer found
sprintf(timername, "hw:CLASS=%i,SCLASS=%i,CARD=%i,DEV=%i,SUBDEV=%i", devclass, sclass, card, device, subdevice);
if ((err = snd_timer_open(&handle, timername, SND_TIMER_OPEN_NONBLOCK))<0) {
fprintf(stderr, "AlsaTimer::initTimer(): timer open %i (%s)\n", err, snd_strerror(err));
return -1;
}
if ((err = snd_timer_info(handle, info)) < 0) {
fprintf(stderr, "AlsaTimer::initTimer(): timer info %i (%s)\n", err, snd_strerror(err));
return -1;
}
//if(debugMsg)
fprintf(stderr, "AlsaTimer::initTimer(): best available ALSA timer: %s\n", snd_timer_info_get_name(info));
snd_timer_params_set_auto_start(params, 1);
snd_timer_params_set_ticks(params, 1);
if ((err = snd_timer_params(handle, params)) < 0) {
fprintf(stderr, "AlsaTimer::initTimer(): timer params %i (%s)\n", err, snd_strerror(err));
return -1;
}
count = snd_timer_poll_descriptors_count(handle);
fds = (pollfd *)calloc(count, sizeof(pollfd));
if (fds == NULL) {
fprintf(stderr, "AlsaTimer::initTimer(): malloc error\n");
return -1;
}
if ((err = snd_timer_poll_descriptors(handle, fds, count)) < 0) {
fprintf(stderr, "AlsaTimer::initTimer(): snd_timer_poll_descriptors error: %s\n", snd_strerror(err));
return -1;
}
return fds->fd;
}
unsigned int AlsaTimer::setTimerResolution(unsigned int resolution)
{
if(TIMER_DEBUG)
printf("AlsaTimer::setTimerResolution(%d)\n",resolution);
/* Resolution of an AlsaTimer is fixed - it cannot be set */
return 0;
}
unsigned int AlsaTimer::setTimerFreq(unsigned int freq)
{
signed int err;
unsigned int setTick, actFreq;
if(TIMER_DEBUG)
printf("AlsaTimer::setTimerFreq(this=%p)\n",this);
setTick = (1000000000 / snd_timer_info_get_resolution(info)) / freq;
if (setTick == 0) {
// return, print error if freq is below 500 (timing will suffer)
if (((1000000000.0 / snd_timer_info_get_resolution(info)) / snd_timer_params_get_ticks(params)) < 500) {
fprintf(stderr,"AlsaTimer::setTimerTicks(): requested freq %u Hz too high for timer (max is %g)\n",
freq, 1000000000.0 / snd_timer_info_get_resolution(info));
fprintf(stderr," freq stays at %ld Hz\n",
(long int)((1000000000.0 / snd_timer_info_get_resolution(info)) / snd_timer_params_get_ticks(params)));
}
return (long int)((1000000000.0 / snd_timer_info_get_resolution(info)) / snd_timer_params_get_ticks(params));
}
actFreq = (1000000000 / snd_timer_info_get_resolution(info)) / setTick;
if (actFreq != freq) {
fprintf(stderr,"AlsaTimer::setTimerTicks(): warning: requested %u Hz, actual freq is %u Hz\n",
freq, actFreq);
}
if(TIMER_DEBUG)
printf("AlsaTimer::setTimerFreq(): Setting ticks (period) to %d ticks\n", setTick);
snd_timer_params_set_auto_start(params, 1);
snd_timer_params_set_ticks(params, setTick);
if ((err = snd_timer_params(handle, params)) < 0) {
fprintf(stderr, "AlsaTimer::setTimerFreq(): timer params %i (%s)\n", err, snd_strerror(err));
return 0;
}
return actFreq;
}
unsigned int AlsaTimer::getTimerResolution()
{
return snd_timer_info_get_resolution(info);
}
unsigned int AlsaTimer::getTimerFreq()
{
return (1000000000 / snd_timer_info_get_resolution(info)) / snd_timer_params_get_ticks(params);
}
bool AlsaTimer::startTimer()
{
if(TIMER_DEBUG)
printf("AlsaTimer::startTimer(this=%p): handle=%p\n",this,handle);
int err;
if ((err = snd_timer_start(handle)) < 0) {
fprintf(stderr, "AlsaTimer::startTimer(): timer start %i (%s)\n", err, snd_strerror(err));
return false;
}
return true;
}
bool AlsaTimer::stopTimer()
{
int err;
if(TIMER_DEBUG)
printf("AlsaTimer::stopTimer(this=%p): handle=%p\n",this,handle);
if ((err = snd_timer_stop(handle)) < 0) {
fprintf(stderr, "AlsaTimer::stopTimer(): timer stop %i (%s)\n", err, snd_strerror(err));
return false;
}
return true;
}
unsigned int AlsaTimer::getTimerTicks(bool printTicks)
{
//if(TIMER_DEBUG)
// printf("AlsaTimer::getTimerTicks\n");
snd_timer_read_t tr;
tr.ticks = 0;
while (snd_timer_read(handle, &tr, sizeof(tr)) == sizeof(tr)) {
if (printTicks) {
printf("TIMER: resolution = %uns, ticks = %u\n",
tr.resolution, tr.ticks);
}
}
return tr.ticks;
}
} // namespace MusECore
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