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// TODO: This should support multiple audio sources.
#include <assert.h>
#include <audio.h>
#include <ctype.h>
#include <drivers/ac97.h>
#include <errno.h>
#include <fs/devfs.h>
#include <math.h>
int audio_write(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
(void)offset;
(void)fd;
int rc = ac97_add_pcm(buffer, len);
if (0 == rc) {
return -EWOULDBLOCK;
}
return rc;
}
int audio_can_write(vfs_inode_t *inode) {
(void)inode;
return ac97_can_write();
}
int volume_write(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
(void)offset;
(void)fd;
int volume = 0;
size_t i = 0;
for (; i < len; i++) {
u8 c = buffer[i];
if (!isdigit(c)) {
break;
}
volume *= 10;
volume += c - '0';
if (volume > 100) {
volume = 100;
break;
}
}
if (0 == i) {
return 0;
}
ac97_set_volume(volume);
return i;
}
int volume_read(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
if (offset > 0) {
return 0;
}
(void)fd;
if (len < 3) {
return 0;
}
int volume = ac97_get_volume();
assert(volume <= 100);
if (volume == 100) {
memcpy(buffer, "100", 3);
return 3;
}
buffer[1] = (volume % 10) + '0';
buffer[0] = ((volume - (volume % 10)) / 10) + '0';
return 2;
}
static int add_files(void) {
devfs_add_file("/audio", NULL, audio_write, NULL, NULL, audio_can_write,
FS_TYPE_CHAR_DEVICE);
devfs_add_file("/volume", volume_read, volume_write, NULL, always_has_data,
always_can_write, FS_TYPE_BLOCK_DEVICE);
return 1;
}
void audio_init(void) {
ac97_init();
add_files();
}
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