kopia lustrzana https://github.com/espressif/esp-idf
96 wiersze
2.5 KiB
C
96 wiersze
2.5 KiB
C
|
#include <string.h>
|
||
|
#include "esp_vfs.h"
|
||
|
#include "esp_attr.h"
|
||
|
#include "sys/errno.h"
|
||
|
#include "sys/lock.h"
|
||
|
#include "soc/uart_struct.h"
|
||
|
|
||
|
static uart_dev_t* s_uarts[3] = {&UART0, &UART1, &UART2};
|
||
|
|
||
|
static int IRAM_ATTR uart_open(const char * path, int flags, int mode)
|
||
|
{
|
||
|
// this is fairly primitive, we should check if file is opened read only,
|
||
|
// and error out if write is requested
|
||
|
if (strcmp(path, "/0") == 0) {
|
||
|
return 0;
|
||
|
} else if (strcmp(path, "/1") == 0) {
|
||
|
return 1;
|
||
|
} else if (strcmp(path, "/2") == 0) {
|
||
|
return 2;
|
||
|
}
|
||
|
errno = ENOENT;
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
static void IRAM_ATTR uart_tx_char(uart_dev_t* uart, int c)
|
||
|
{
|
||
|
while (uart->status.txfifo_cnt >= 127) {
|
||
|
;
|
||
|
}
|
||
|
uart->fifo.rw_byte = c;
|
||
|
}
|
||
|
|
||
|
|
||
|
static size_t IRAM_ATTR uart_write(int fd, const void * data, size_t size)
|
||
|
{
|
||
|
assert(fd >=0 && fd < 3);
|
||
|
const char *data_c = (const char *)data;
|
||
|
uart_dev_t* uart = s_uarts[fd];
|
||
|
static _lock_t stdout_lock; /* lazily initialised */
|
||
|
/* Even though newlib does stream locking on stdout, we need
|
||
|
a dedicated stdout UART lock...
|
||
|
|
||
|
This is because each task has its own _reent structure with
|
||
|
unique FILEs for stdin/stdout/stderr, so these are
|
||
|
per-thread (lazily initialised by __sinit the first time a
|
||
|
stdio function is used, see findfp.c:235.
|
||
|
|
||
|
It seems like overkill to allocate a FILE-per-task and lock
|
||
|
a thread-local stream, but I see no easy way to fix this
|
||
|
(pre-__sinit_, tasks have "fake" FILEs ie __sf_fake_stdout
|
||
|
which aren't fully valid.)
|
||
|
*/
|
||
|
_lock_acquire_recursive(&stdout_lock);
|
||
|
for (size_t i = 0; i < size; i++) {
|
||
|
#if CONFIG_NEWLIB_STDOUT_ADDCR
|
||
|
if (data_c[i]=='\n') {
|
||
|
uart_tx_char(uart, '\r');
|
||
|
}
|
||
|
#endif
|
||
|
uart_tx_char(uart, data_c[i]);
|
||
|
}
|
||
|
_lock_release_recursive(&stdout_lock);
|
||
|
return size;
|
||
|
}
|
||
|
|
||
|
static int IRAM_ATTR uart_fstat(int fd, struct stat * st)
|
||
|
{
|
||
|
assert(fd >=0 && fd < 3);
|
||
|
st->st_mode = S_IFCHR;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int IRAM_ATTR uart_close(int fd)
|
||
|
{
|
||
|
assert(fd >=0 && fd < 3);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
void esp_vfs_dev_uart_register()
|
||
|
{
|
||
|
esp_vfs_t vfs = {
|
||
|
.fd_offset = 0,
|
||
|
.flags = ESP_VFS_FLAG_DEFAULT,
|
||
|
.write = &uart_write,
|
||
|
.open = &uart_open,
|
||
|
.fstat = &uart_fstat,
|
||
|
.close = &uart_close,
|
||
|
.read = NULL, // TODO: implement reading from UART
|
||
|
.stat = NULL,
|
||
|
.link = NULL,
|
||
|
.unlink = NULL,
|
||
|
.rename = NULL
|
||
|
};
|
||
|
ESP_ERROR_CHECK(esp_vfs_register("/dev/uart", &vfs, NULL));
|
||
|
}
|