zephyr/drivers/serial/uart_native_ptty.c

280 lines
6.6 KiB
C

/*
* Copyright (c) 2018, Oticon A/S
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT zephyr_native_posix_uart
#include <stdbool.h>
#include <zephyr/drivers/uart.h>
#include <zephyr/kernel.h>
#include "cmdline.h" /* native_posix command line options header */
#include "posix_native_task.h"
#include "uart_native_ptty_bottom.h"
#include "nsi_host_trampolines.h"
/*
* UART driver for POSIX ARCH based boards.
* It can support up to two UARTs.
*
* For the first UART:
*
* It can either be connected to the process STDIN+STDOUT
* OR
* to a dedicated pseudo terminal
*
* The 2nd option is the recommended one for interactive use, as the pseudo
* terminal driver will be configured in "raw" mode, and will therefore behave
* more like a real UART.
*
* When connected to its own pseudo terminal, it may also auto attach a terminal
* emulator to it, if set so from command line.
*/
static int np_uart_stdin_poll_in(const struct device *dev,
unsigned char *p_char);
static int np_uart_tty_poll_in(const struct device *dev,
unsigned char *p_char);
static void np_uart_poll_out(const struct device *dev,
unsigned char out_char);
static bool auto_attach;
static bool wait_pts;
static char *auto_attach_cmd = CONFIG_NATIVE_UART_AUTOATTACH_DEFAULT_CMD;
struct native_uart_status {
int out_fd; /* File descriptor used for output */
int in_fd; /* File descriptor used for input */
};
static struct native_uart_status native_uart_status_0;
static struct uart_driver_api np_uart_driver_api_0 = {
.poll_out = np_uart_poll_out,
.poll_in = np_uart_tty_poll_in,
};
#if defined(CONFIG_UART_NATIVE_POSIX_PORT_1_ENABLE)
static struct native_uart_status native_uart_status_1;
static struct uart_driver_api np_uart_driver_api_1 = {
.poll_out = np_uart_poll_out,
.poll_in = np_uart_tty_poll_in,
};
#endif /* CONFIG_UART_NATIVE_POSIX_PORT_1_ENABLE */
#define ERROR posix_print_error_and_exit
#define WARN posix_print_warning
/**
* @brief Initialize the first native_posix serial port
*
* @param dev UART_0 device struct
*
* @return 0 (if it fails catastrophically, the execution is terminated)
*/
static int np_uart_0_init(const struct device *dev)
{
struct native_uart_status *d;
d = (struct native_uart_status *)dev->data;
if (IS_ENABLED(CONFIG_NATIVE_UART_0_ON_OWN_PTY)) {
int tty_fn = np_uart_open_ptty(dev->name, auto_attach_cmd, auto_attach, wait_pts);
d->in_fd = tty_fn;
d->out_fd = tty_fn;
np_uart_driver_api_0.poll_in = np_uart_tty_poll_in;
} else { /* NATIVE_UART_0_ON_STDINOUT */
d->in_fd = np_uart_ptty_get_stdin_fileno();
d->out_fd = np_uart_ptty_get_stdout_fileno();
np_uart_driver_api_0.poll_in = np_uart_stdin_poll_in;
}
return 0;
}
#if defined(CONFIG_UART_NATIVE_POSIX_PORT_1_ENABLE)
/*
* Initialize the 2nd UART port.
* This port will be always attached to its own new pseudoterminal.
*/
static int np_uart_1_init(const struct device *dev)
{
struct native_uart_status *d;
int tty_fn;
d = (struct native_uart_status *)dev->data;
tty_fn = np_uart_open_ptty(dev->name, NULL, false, wait_pts);
d->in_fd = tty_fn;
d->out_fd = tty_fn;
return 0;
}
#endif
/*
* @brief Output a character towards the serial port
*
* @param dev UART device struct
* @param out_char Character to send.
*/
static void np_uart_poll_out(const struct device *dev,
unsigned char out_char)
{
int ret;
struct native_uart_status *d = (struct native_uart_status *)dev->data;
if (wait_pts) {
while (1) {
int rc = np_uart_slave_connected(d->out_fd);
if (rc == 1) {
break;
}
k_sleep(K_MSEC(100));
}
}
/* The return value of write() cannot be ignored (there is a warning)
* but we do not need the return value for anything.
*/
ret = nsi_host_write(d->out_fd, &out_char, 1);
(void) ret;
}
/**
* @brief Poll the device for input.
*
* @param dev UART device structure.
* @param p_char Pointer to character.
*
* @retval 0 If a character arrived and was stored in p_char
* @retval -1 If no character was available to read
*/
static int np_uart_stdin_poll_in(const struct device *dev,
unsigned char *p_char)
{
int in_f = ((struct native_uart_status *)dev->data)->in_fd;
static bool disconnected;
int rc;
if (disconnected == true) {
return -1;
}
rc = np_uart_stdin_poll_in_bottom(in_f, p_char);
if (rc == -2) {
disconnected = true;
return -1;
}
return rc;
}
/**
* @brief Poll the device for input.
*
* @param dev UART device structure.
* @param p_char Pointer to character.
*
* @retval 0 If a character arrived and was stored in p_char
* @retval -1 If no character was available to read
*/
static int np_uart_tty_poll_in(const struct device *dev,
unsigned char *p_char)
{
int n = -1;
int in_f = ((struct native_uart_status *)dev->data)->in_fd;
n = nsi_host_read(in_f, p_char, 1);
if (n == -1) {
return -1;
}
return 0;
}
DEVICE_DT_INST_DEFINE(0,
np_uart_0_init, NULL,
(void *)&native_uart_status_0, NULL,
PRE_KERNEL_1, CONFIG_SERIAL_INIT_PRIORITY,
&np_uart_driver_api_0);
#if defined(CONFIG_UART_NATIVE_POSIX_PORT_1_ENABLE)
DEVICE_DT_INST_DEFINE(1,
np_uart_1_init, NULL,
(void *)&native_uart_status_1, NULL,
PRE_KERNEL_1, CONFIG_SERIAL_INIT_PRIORITY,
&np_uart_driver_api_1);
#endif /* CONFIG_UART_NATIVE_POSIX_PORT_1_ENABLE */
static void auto_attach_cmd_cb(char *argv, int offset)
{
auto_attach_cmd = &argv[offset];
auto_attach = true;
}
static void np_add_uart_options(void)
{
if (!IS_ENABLED(CONFIG_NATIVE_UART_0_ON_OWN_PTY)) {
return;
}
static struct args_struct_t uart_options[] = {
{
.is_switch = true,
.option = "attach_uart",
.type = 'b',
.dest = (void *)&auto_attach,
.descript = "Automatically attach to the UART terminal"
},
{
.option = "attach_uart_cmd",
.name = "\"cmd\"",
.type = 's',
.call_when_found = auto_attach_cmd_cb,
.descript = "Command used to automatically attach to the terminal (implies "
"auto_attach), by default: "
"'" CONFIG_NATIVE_UART_AUTOATTACH_DEFAULT_CMD "'"
},
IF_ENABLED(CONFIG_UART_NATIVE_WAIT_PTS_READY_ENABLE, (
{
.is_switch = true,
.option = "wait_uart",
.type = 'b',
.dest = (void *)&wait_pts,
.descript = "Hold writes to the uart/pts until a client is connected/ready"
},
))
ARG_TABLE_ENDMARKER
};
native_add_command_line_opts(uart_options);
}
static void np_cleanup_uart(void)
{
if (IS_ENABLED(CONFIG_NATIVE_UART_0_ON_OWN_PTY)) {
if (native_uart_status_0.in_fd != 0) {
nsi_host_close(native_uart_status_0.in_fd);
}
}
#if defined(CONFIG_UART_NATIVE_POSIX_PORT_1_ENABLE)
if (native_uart_status_1.in_fd != 0) {
nsi_host_close(native_uart_status_1.in_fd);
}
#endif
}
NATIVE_TASK(np_add_uart_options, PRE_BOOT_1, 11);
NATIVE_TASK(np_cleanup_uart, ON_EXIT, 99);