rt-thread-official/components/drivers/serial/serial_tty.c

322 lines
7.4 KiB
C

/*
* Copyright (c) 2006-2023, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2023-11-21 Shell init ver.
*/
#define DBG_TAG "drivers.serial"
#define DBG_LVL DBG_INFO
#include <rtdbg.h>
#include <rthw.h>
#include <rtthread.h>
#include <rtdevice.h>
#include <terminal/terminal.h>
#define TTY_NAME_PREFIX "S" /* (S)erial */
#define LWP_TTY_WORKQUEUE_PRIORITY 3
struct serial_tty_context
{
struct rt_serial_device *parent;
struct rt_device_notify backup_notify;
struct rt_work work;
};
static struct rt_workqueue *_ttyworkq; /* system work queue */
static rt_atomic_t _device_id_counter = 0;
static long get_dec_digits(rt_ubase_t val)
{
long result = 1;
while (1)
{
if (val < 10)
return result;
if (val < 100)
return result + 1;
if (val < 1000)
return result + 2;
if (val < 10000)
return result + 3;
val /= 10000U;
result += 4;
}
return result;
}
static char *alloc_device_name(void)
{
char *tty_dev_name;
unsigned int devid = rt_atomic_add(&_device_id_counter, 1);
long digits_len = (sizeof(TTY_NAME_PREFIX) - 1) /* raw prefix */
+ get_dec_digits(devid) + 1; /* tailing \0 */
tty_dev_name = rt_malloc(digits_len);
if (tty_dev_name)
rt_sprintf(tty_dev_name, "%s%u", TTY_NAME_PREFIX, devid);
return tty_dev_name;
}
static void _tty_rx_notify(struct rt_device *device)
{
lwp_tty_t tp;
struct serial_tty_context *softc;
tp = rt_container_of(device, struct lwp_tty, parent);
RT_ASSERT(tp);
softc = tty_softc(tp);
if (_ttyworkq)
rt_workqueue_submit_work(_ttyworkq, &softc->work, 0);
}
static void _tty_rx_worker(struct rt_work *work, void *data)
{
char input;
rt_ssize_t readbytes;
lwp_tty_t tp = data;
struct serial_tty_context *softc;
struct rt_serial_device *serial;
tty_lock(tp);
while (1)
{
softc = tty_softc(tp);
serial = softc->parent;
readbytes = rt_device_read(&serial->parent, -1, &input, 1);
if (readbytes != 1)
{
break;
}
ttydisc_rint(tp, input, 0);
}
ttydisc_rint_done(tp);
tty_unlock(tp);
}
rt_inline void _setup_serial(struct rt_serial_device *serial, lwp_tty_t tp,
struct serial_tty_context *softc)
{
struct rt_device_notify notify;
softc->backup_notify = serial->rx_notify;
notify.dev = &tp->parent;
notify.notify = _tty_rx_notify;
rt_device_init(&serial->parent);
rt_work_init(&softc->work, _tty_rx_worker, tp);
rt_device_control(&serial->parent, RT_DEVICE_CTRL_NOTIFY_SET, &notify);
}
rt_inline void _restore_serial(struct rt_serial_device *serial, lwp_tty_t tp,
struct serial_tty_context *softc)
{
rt_device_control(&serial->parent, RT_DEVICE_CTRL_NOTIFY_SET, &softc->backup_notify);
}
static int _serial_isbusy(struct rt_serial_device *serial)
{
rt_thread_t user_thread = rt_console_current_user();
rt_thread_t self_thread = rt_thread_self();
return rt_console_get_device() == &serial->parent &&
(user_thread != RT_NULL && user_thread != self_thread);
}
static void serial_tty_outwakeup(struct lwp_tty *tp)
{
char out_char;
int len;
struct serial_tty_context *context = tty_softc(tp);
struct rt_serial_device *device;
if (!context || !context->parent)
{
LOG_E("%s: Data corruption", __func__);
return;
}
device = context->parent;
if (_serial_isbusy(device))
{
return ;
}
while ((len = ttydisc_getc(tp, &out_char, sizeof(out_char))) != 0)
{
device->ops->putc(device, out_char);
/* discard remaining if emergency output is happened */
if (_serial_isbusy(device))
{
break;
}
}
}
static int serial_tty_open(struct lwp_tty *tp)
{
struct serial_tty_context *softc;
struct rt_serial_device *serial;
rt_err_t error;
int oflags;
softc = tty_softc(tp);
serial = softc->parent;
LOG_D("%s", __func__);
rt_device_control(&serial->parent, RT_DEVICE_CTRL_CONSOLE_OFLAG, &oflags);
error = rt_device_open(&serial->parent, oflags);
if (!error)
{
/**
* to avoid driver accesssing null data,
* these are setup only after tty is registered
*/
_setup_serial(serial, tp, softc);
}
return error;
}
static void serial_tty_close(struct lwp_tty *tp)
{
struct serial_tty_context *softc;
struct rt_serial_device *serial;
softc = tty_softc(tp);
serial = softc->parent;
LOG_D("%s", __func__);
_restore_serial(serial, tp, softc);
rt_device_close(&serial->parent);
}
static int serial_tty_ioctl(struct lwp_tty *tp, rt_ubase_t cmd, rt_caddr_t data,
struct rt_thread *td)
{
int error;
switch (cmd)
{
default:
/**
* Note: for the most case, we don't let serial layer handle ioctl,
* for that they can't act properly regarding to the process
* management system, since it is unawared of that. So a ENOSYS is
* returned and caused the TTY layer to handle ioctl itself.
*/
error = -ENOSYS;
break;
}
return error;
}
static struct lwp_ttydevsw serial_ttydevsw = {
.tsw_open = serial_tty_open,
.tsw_close = serial_tty_close,
.tsw_ioctl = serial_tty_ioctl,
.tsw_outwakeup = serial_tty_outwakeup,
};
rt_err_t rt_hw_serial_register_tty(struct rt_serial_device *serial)
{
rt_err_t rc;
lwp_tty_t tty;
char *dev_name;
struct serial_tty_context *softc;
if (serial->rx_notify.dev)
{
return -RT_EBUSY;
}
softc = rt_malloc(sizeof(struct serial_tty_context));
if (softc)
{
dev_name = alloc_device_name();
if (dev_name)
{
softc->parent = serial;
tty = lwp_tty_create(&serial_ttydevsw, softc);
if (tty)
{
rc = lwp_tty_register(tty, dev_name);
if (rc != RT_EOK)
{
rt_free(tty);
rt_free(softc);
}
}
else
{
rt_free(softc);
rc = -RT_ENOMEM;
}
rt_free(dev_name);
}
else
{
rt_free(softc);
rc = -RT_ENOMEM;
}
}
else
{
rc = -RT_ENOMEM;
}
return rc;
}
rt_err_t rt_hw_serial_unregister_tty(struct rt_serial_device *serial)
{
rt_device_t tty_dev;
lwp_tty_t tp;
struct serial_tty_context *softc;
tty_dev = serial->rx_notify.dev;
tp = rt_container_of(tty_dev, struct lwp_tty, parent);
/* restore serial setting */
softc = tty_softc(tp);
serial->rx_notify = softc->backup_notify;
tty_rel_gone(tp);
/* device unregister? */
rt_device_destroy(&tp->parent);
/* resource free? */
lwp_tty_delete(tp);
return RT_EOK;
}
static int _tty_workqueue_init(void)
{
if (_ttyworkq != RT_NULL)
return RT_EOK;
_ttyworkq = rt_workqueue_create("ttyworkq", RT_SYSTEM_WORKQUEUE_STACKSIZE,
LWP_TTY_WORKQUEUE_PRIORITY);
RT_ASSERT(_ttyworkq != RT_NULL);
return RT_EOK;
}
INIT_PREV_EXPORT(_tty_workqueue_init);