zephyr/subsys/console/getchar.c

164 lines
3.1 KiB
C

/*
* Copyright (c) 2017 Linaro Limited.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr.h>
#include <uart.h>
#include <misc/printk.h>
#include <console.h>
#include <drivers/console/console.h>
#include <drivers/console/uart_console.h>
struct tty_serial {
struct device *uart_dev;
struct k_sem rx_sem;
u8_t *rx_ringbuf;
u32_t rx_ringbuf_sz;
u16_t rx_get, rx_put;
u8_t *tx_ringbuf;
u32_t tx_ringbuf_sz;
u16_t tx_get, tx_put;
};
static u8_t console_rxbuf[CONFIG_CONSOLE_GETCHAR_BUFSIZE];
static u8_t console_txbuf[CONFIG_CONSOLE_PUTCHAR_BUFSIZE];
static int tty_irq_input_hook(struct tty_serial *tty, u8_t c);
static struct tty_serial console_serial;
static void tty_uart_isr(void *user_data)
{
struct tty_serial *tty = user_data;
struct device *dev = tty->uart_dev;
uart_irq_update(dev);
if (uart_irq_rx_ready(dev)) {
u8_t c;
while (1) {
if (uart_fifo_read(dev, &c, 1) == 0) {
break;
}
tty_irq_input_hook(tty, c);
}
}
if (uart_irq_tx_ready(dev)) {
if (tty->tx_get == tty->tx_put) {
/* Output buffer empty, don't bother
* us with tx interrupts
*/
uart_irq_tx_disable(dev);
} else {
uart_fifo_fill(dev, &tty->tx_ringbuf[tty->tx_get++], 1);
if (tty->tx_get >= tty->tx_ringbuf_sz) {
tty->tx_get = 0;
}
}
}
}
static int tty_irq_input_hook(struct tty_serial *tty, u8_t c)
{
int rx_next = tty->rx_put + 1;
if (rx_next >= tty->rx_ringbuf_sz) {
rx_next = 0;
}
if (rx_next == tty->rx_get) {
/* Try to give a clue to user that some input was lost */
console_putchar('~');
console_putchar('\n');
return 1;
}
tty->rx_ringbuf[tty->rx_put] = c;
tty->rx_put = rx_next;
k_sem_give(&tty->rx_sem);
return 1;
}
int tty_putchar(struct tty_serial *tty, char c)
{
unsigned int key;
int tx_next;
key = irq_lock();
tx_next = tty->tx_put + 1;
if (tx_next >= tty->tx_ringbuf_sz) {
tx_next = 0;
}
if (tx_next == tty->tx_get) {
irq_unlock(key);
return -1;
}
tty->tx_ringbuf[tty->tx_put] = (u8_t)c;
tty->tx_put = tx_next;
irq_unlock(key);
uart_irq_tx_enable(tty->uart_dev);
return 0;
}
u8_t tty_getchar(struct tty_serial *tty)
{
unsigned int key;
u8_t c;
k_sem_take(&tty->rx_sem, K_FOREVER);
key = irq_lock();
c = tty->rx_ringbuf[tty->rx_get++];
if (tty->rx_get >= tty->rx_ringbuf_sz) {
tty->rx_get = 0;
}
irq_unlock(key);
return c;
}
void tty_init(struct tty_serial *tty, struct device *uart_dev,
u8_t *rxbuf, u16_t rxbuf_sz,
u8_t *txbuf, u16_t txbuf_sz)
{
tty->uart_dev = uart_dev;
tty->rx_ringbuf = rxbuf;
tty->rx_ringbuf_sz = rxbuf_sz;
tty->tx_ringbuf = txbuf;
tty->tx_ringbuf_sz = txbuf_sz;
tty->rx_get = tty->rx_put = tty->tx_get = tty->tx_put = 0;
k_sem_init(&tty->rx_sem, 0, UINT_MAX);
uart_irq_callback_user_data_set(uart_dev, tty_uart_isr, tty);
uart_irq_rx_enable(uart_dev);
}
int console_putchar(char c)
{
return tty_putchar(&console_serial, c);
}
u8_t console_getchar(void)
{
return tty_getchar(&console_serial);
}
void console_init(void)
{
struct device *uart_dev;
uart_dev = device_get_binding(CONFIG_UART_CONSOLE_ON_DEV_NAME);
tty_init(&console_serial, uart_dev,
console_rxbuf, sizeof(console_rxbuf),
console_txbuf, sizeof(console_txbuf));
}