linux/sound/oss/sh_dac_audio.c
Arjan van de Ven 9c2e08c592 [PATCH] mark struct file_operations const 9
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00

331 lines
6.4 KiB
C

/*
* sound/oss/sh_dac_audio.c
*
* SH DAC based sound :(
*
* Copyright (C) 2004,2005 Andriy Skulysh
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/linkage.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/sound.h>
#include <linux/soundcard.h>
#include <linux/interrupt.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/irq.h>
#include <asm/delay.h>
#include <asm/clock.h>
#include <asm/cpu/dac.h>
#include <asm/cpu/timer.h>
#include <asm/machvec.h>
#include <asm/hp6xx.h>
#include <asm/hd64461.h>
#define MODNAME "sh_dac_audio"
#define TMU_TOCR_INIT 0x00
#define TMU1_TCR_INIT 0x0020 /* Clock/4, rising edge; interrupt on */
#define TMU1_TSTR_INIT 0x02 /* Bit to turn on TMU1 */
#define BUFFER_SIZE 48000
static int rate;
static int empty;
static char *data_buffer, *buffer_begin, *buffer_end;
static int in_use, device_major;
static void dac_audio_start_timer(void)
{
u8 tstr;
tstr = ctrl_inb(TMU_TSTR);
tstr |= TMU1_TSTR_INIT;
ctrl_outb(tstr, TMU_TSTR);
}
static void dac_audio_stop_timer(void)
{
u8 tstr;
tstr = ctrl_inb(TMU_TSTR);
tstr &= ~TMU1_TSTR_INIT;
ctrl_outb(tstr, TMU_TSTR);
}
static void dac_audio_reset(void)
{
dac_audio_stop_timer();
buffer_begin = buffer_end = data_buffer;
empty = 1;
}
static void dac_audio_sync(void)
{
while (!empty)
schedule();
}
static void dac_audio_start(void)
{
if (mach_is_hp6xx()) {
u16 v = inw(HD64461_GPADR);
v &= ~HD64461_GPADR_SPEAKER;
outw(v, HD64461_GPADR);
}
sh_dac_enable(CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
ctrl_outw(TMU1_TCR_INIT, TMU1_TCR);
}
static void dac_audio_stop(void)
{
dac_audio_stop_timer();
if (mach_is_hp6xx()) {
u16 v = inw(HD64461_GPADR);
v |= HD64461_GPADR_SPEAKER;
outw(v, HD64461_GPADR);
}
sh_dac_output(0, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
sh_dac_disable(CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
}
static void dac_audio_set_rate(void)
{
unsigned long interval;
struct clk *clk;
clk = clk_get("module_clk");
interval = (clk_get_rate(clk) / 4) / rate;
clk_put(clk);
ctrl_outl(interval, TMU1_TCOR);
ctrl_outl(interval, TMU1_TCNT);
}
static int dac_audio_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int val;
switch (cmd) {
case OSS_GETVERSION:
return put_user(SOUND_VERSION, (int *)arg);
case SNDCTL_DSP_SYNC:
dac_audio_sync();
return 0;
case SNDCTL_DSP_RESET:
dac_audio_reset();
return 0;
case SNDCTL_DSP_GETFMTS:
return put_user(AFMT_U8, (int *)arg);
case SNDCTL_DSP_SETFMT:
return put_user(AFMT_U8, (int *)arg);
case SNDCTL_DSP_NONBLOCK:
file->f_flags |= O_NONBLOCK;
return 0;
case SNDCTL_DSP_GETCAPS:
return 0;
case SOUND_PCM_WRITE_RATE:
val = *(int *)arg;
if (val > 0) {
rate = val;
dac_audio_set_rate();
}
return put_user(rate, (int *)arg);
case SNDCTL_DSP_STEREO:
return put_user(0, (int *)arg);
case SOUND_PCM_WRITE_CHANNELS:
return put_user(1, (int *)arg);
case SNDCTL_DSP_SETDUPLEX:
return -EINVAL;
case SNDCTL_DSP_PROFILE:
return -EINVAL;
case SNDCTL_DSP_GETBLKSIZE:
return put_user(BUFFER_SIZE, (int *)arg);
case SNDCTL_DSP_SETFRAGMENT:
return 0;
default:
printk(KERN_ERR "sh_dac_audio: unimplemented ioctl=0x%x\n",
cmd);
return -EINVAL;
}
return -EINVAL;
}
static ssize_t dac_audio_write(struct file *file, const char *buf, size_t count,
loff_t * ppos)
{
int free;
int nbytes;
if (count < 0)
return -EINVAL;
if (!count) {
dac_audio_sync();
return 0;
}
free = buffer_begin - buffer_end;
if (free < 0)
free += BUFFER_SIZE;
if ((free == 0) && (empty))
free = BUFFER_SIZE;
if (count > free)
count = free;
if (buffer_begin > buffer_end) {
if (copy_from_user((void *)buffer_end, buf, count))
return -EFAULT;
buffer_end += count;
} else {
nbytes = data_buffer + BUFFER_SIZE - buffer_end;
if (nbytes > count) {
if (copy_from_user((void *)buffer_end, buf, count))
return -EFAULT;
buffer_end += count;
} else {
if (copy_from_user((void *)buffer_end, buf, nbytes))
return -EFAULT;
if (copy_from_user
((void *)data_buffer, buf + nbytes, count - nbytes))
return -EFAULT;
buffer_end = data_buffer + count - nbytes;
}
}
if (empty) {
empty = 0;
dac_audio_start_timer();
}
return count;
}
static ssize_t dac_audio_read(struct file *file, char *buf, size_t count,
loff_t * ppos)
{
return -EINVAL;
}
static int dac_audio_open(struct inode *inode, struct file *file)
{
if (file->f_mode & FMODE_READ)
return -ENODEV;
if (in_use)
return -EBUSY;
in_use = 1;
dac_audio_start();
return 0;
}
static int dac_audio_release(struct inode *inode, struct file *file)
{
dac_audio_sync();
dac_audio_stop();
in_use = 0;
return 0;
}
const struct file_operations dac_audio_fops = {
.read = dac_audio_read,
.write = dac_audio_write,
.ioctl = dac_audio_ioctl,
.open = dac_audio_open,
.release = dac_audio_release,
};
static irqreturn_t timer1_interrupt(int irq, void *dev)
{
unsigned long timer_status;
timer_status = ctrl_inw(TMU1_TCR);
timer_status &= ~0x100;
ctrl_outw(timer_status, TMU1_TCR);
if (!empty) {
sh_dac_output(*buffer_begin, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
buffer_begin++;
if (buffer_begin == data_buffer + BUFFER_SIZE)
buffer_begin = data_buffer;
if (buffer_begin == buffer_end) {
empty = 1;
dac_audio_stop_timer();
}
}
return IRQ_HANDLED;
}
static int __init dac_audio_init(void)
{
int retval;
if ((device_major = register_sound_dsp(&dac_audio_fops, -1)) < 0) {
printk(KERN_ERR "Cannot register dsp device");
return device_major;
}
in_use = 0;
data_buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL);
if (data_buffer == NULL)
return -ENOMEM;
dac_audio_reset();
rate = 8000;
dac_audio_set_rate();
retval =
request_irq(TIMER1_IRQ, timer1_interrupt, IRQF_DISABLED, MODNAME, 0);
if (retval < 0) {
printk(KERN_ERR "sh_dac_audio: IRQ %d request failed\n",
TIMER1_IRQ);
return retval;
}
return 0;
}
static void __exit dac_audio_exit(void)
{
free_irq(TIMER1_IRQ, 0);
unregister_sound_dsp(device_major);
kfree((void *)data_buffer);
}
module_init(dac_audio_init);
module_exit(dac_audio_exit);
MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
MODULE_DESCRIPTION("SH DAC sound driver");
MODULE_LICENSE("GPL");