-/**
- * \file
- * <!--
- * This file is part of BeRTOS.
- *
- * Bertos is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * As a special exception, you may use this file as part of a free software
- * library without restriction. Specifically, if other files instantiate
- * templates or use macros or inline functions from this file, or you compile
- * this file and link it with other files to produce an executable, this
- * file does not by itself cause the resulting executable to be covered by
- * the GNU General Public License. This exception does not however
- * invalidate any other reasons why the executable file might be covered by
- * the GNU General Public License.
- *
- * Copyright 2003, 2004, 2006 Develer S.r.l. (http://www.develer.com/)
- * Copyright 2000 Bernardo Innocenti <bernie@codewiz.org>
- *
- * -->
- *
- * \brief Buffered serial I/O driver
- *
- * The serial rx interrupt buffers incoming data in a software FIFO
- * to decouple the higher level protocols from the line speed.
- * Outgoing data is buffered as well for better performance.
- * This driver is not optimized for best performance, but it
- * has proved to be fast enough to handle transfer rates up to
- * 38400bps on a 16MHz 80196.
- *
- * MODULE CONFIGURATION
- *
- * \li \c CONFIG_SER_HWHANDSHAKE - set to 1 to enable RTS/CTS handshake.
- * Support is incomplete/untested.
- * \li \c CONFIG_SER_TXTIMEOUT - Enable software serial transmission timeouts
- *
- *
- * \version $Id$
- * \author Bernardo Innocenti <bernie@develer.com>
- */
-
-#include "ser.h"
-#include "wdt.h"
-#include "ser_p.h"
-#include <mware/formatwr.h>
-#include <cfg/debug.h>
-#include <appconfig.h>
-
-/*
- * Sanity check for config parameters required by this module.
- */
-#if !defined(CONFIG_KERNEL) || ((CONFIG_KERNEL != 0) && CONFIG_KERNEL != 1)
- #error CONFIG_KERNEL must be set to either 0 or 1 in config.h
-#endif
-#if !defined(CONFIG_SER_RXTIMEOUT)
- #error CONFIG_SER_TXTIMEOUT missing in config.h
-#endif
-#if !defined(CONFIG_SER_RXTIMEOUT)
- #error CONFIG_SER_RXTIMEOUT missing in config.h
-#endif
-#if !defined(CONFIG_SER_GETS) || ((CONFIG_SER_GETS != 0) && CONFIG_SER_GETS != 1)
- #error CONFIG_SER_GETS must be set to either 0 or 1 in config.h
-#endif
-#if !defined(CONFIG_SER_DEFBAUDRATE)
- #error CONFIG_SER_DEFBAUDRATE missing in config.h
-#endif
-#if !defined(CONFIG_PRINTF)
- #error CONFIG_PRINTF missing in config.h
-#endif
-
-#if CONFIG_KERNEL
- #include <kern/proc.h>
-#endif
-
-#if CONFIG_SER_TXTIMEOUT != -1 || CONFIG_SER_RXTIMEOUT != -1
- #include <drv/timer.h>
-#endif
-
-
-/* Serial configuration parameters */
-#define SER_CTSDELAY 70 /**< CTS line retry interval (ms) */
-#define SER_TXPOLLDELAY 2 /**< Transmit buffer full retry interval (ms) */
-#define SER_RXPOLLDELAY 2 /**< Receive buffer empty retry interval (ms) */
-
-
-struct Serial ser_handles[SER_CNT];
-
-
-/**
- * Inserisce il carattere c nel buffer di trasmissione.
- * Questa funzione mette il processo chiamante in attesa
- * quando il buffer e' pieno.
- *
- * \return EOF in caso di errore o timeout, altrimenti
- * il carattere inviato.
- */
-int ser_putchar(int c, struct Serial *port)
-{
- //ASSERT_VALID_FIFO(&port->txfifo);
- if (fifo_isfull_locked(&port->txfifo))
- {
-#if CONFIG_SER_TXTIMEOUT != -1
- ticks_t start_time = timer_clock();
-#endif
-
- /* Attende finche' il buffer e' pieno... */
- do
- {
- wdt_reset();
-#if CONFIG_KERNEL && CONFIG_KERN_SCHED
- /* Give up timeslice to other processes. */
- proc_switch();
-#endif
-#if CONFIG_SER_TXTIMEOUT != -1
- if (timer_clock() - start_time >= port->txtimeout)
- {
- ATOMIC(port->status |= SERRF_TXTIMEOUT);
- return EOF;
- }
-#endif /* CONFIG_SER_TXTIMEOUT */
- }
- while (fifo_isfull_locked(&port->txfifo));
- }
-
- fifo_push_locked(&port->txfifo, (unsigned char)c);
-
- /* (re)trigger tx interrupt */
- port->hw->table->txStart(port->hw);
-
- /* Avoid returning signed extended char */
- return (int)((unsigned char)c);
-}
-
-
-/**
- * Preleva un carattere dal buffer di ricezione.
- * Questa funzione mette il processo chiamante in attesa
- * quando il buffer e' vuoto. L'attesa ha un timeout
- * di ser_rxtimeout millisecondi.
- *
- * \return EOF in caso di errore o timeout, altrimenti
- * il carattere ricevuto.
- */
-int ser_getchar(struct Serial *port)
-{
- if (fifo_isempty_locked(&port->rxfifo))
- {
-#if CONFIG_SER_RXTIMEOUT != -1
- ticks_t start_time = timer_clock();
-#endif
- /* Wait while buffer is empty */
- do
- {
- wdt_reset();
-#if CONFIG_KERNEL && CONFIG_KERN_SCHED
- /* Give up timeslice to other processes. */
- proc_switch();
-#endif
-#if CONFIG_SER_RXTIMEOUT != -1
- if (timer_clock() - start_time >= port->rxtimeout)
- {
- ATOMIC(port->status |= SERRF_RXTIMEOUT);
- return EOF;
- }
-#endif /* CONFIG_SER_RXTIMEOUT */
- }
- while (fifo_isempty_locked(&port->rxfifo) && (ser_getstatus(port) & SERRF_RX) == 0);
- }
-
- /*
- * Get a byte from the FIFO (avoiding sign-extension),
- * re-enable RTS, then return result.
- */
- if (ser_getstatus(port) & SERRF_RX)
- return EOF;
- return (int)(unsigned char)fifo_pop_locked(&port->rxfifo);
-}
-
-
-/**
- * Preleva un carattere dal buffer di ricezione.
- * Se il buffer e' vuoto, ser_getchar_nowait() ritorna
- * immediatamente EOF.
- */
-int ser_getchar_nowait(struct Serial *port)
-{
- if (fifo_isempty_locked(&port->rxfifo))
- return EOF;
-
- /* NOTE: the double cast prevents unwanted sign extension */
- return (int)(unsigned char)fifo_pop_locked(&port->rxfifo);
-}
-
-
-#if CONFIG_SER_GETS
-/**
- * Read a line long at most as size and put it
- * in buf.
- * \return number of chars read or EOF in case
- * of error.
- */
-int ser_gets(struct Serial *port, char *buf, int size)
-{
- return ser_gets_echo(port, buf, size, false);
-}
-
-
-/**
- * Read a line long at most as size and put it
- * in buf, with optional echo.
- *
- * \return number of chars read, or EOF in case
- * of error.
- */
-int ser_gets_echo(struct Serial *port, char *buf, int size, bool echo)
-{
- int i = 0;
- int c;
-
- for (;;)
- {
- if ((c = ser_getchar(port)) == EOF)
- {
- buf[i] = '\0';
- return -1;
- }
-
- /* FIXME */
- if (c == '\r' || c == '\n' || i >= size-1)
- {
- buf[i] = '\0';
- if (echo)
- ser_print(port, "\r\n");
- break;
- }
- buf[i++] = c;
- if (echo)
- ser_putchar(c, port);
- }
-
- return i;
-}
-#endif /* !CONFIG_SER_GETS */
-
-
-/**
- * Read at most \a size bytes from \a port and put them in \a buf
- *
- * \return number of bytes actually read, or EOF in
- * case of error.
- */
-int ser_read(struct Serial *port, void *buf, size_t size)
-{
- size_t i = 0;
- char *_buf = (char *)buf;
- int c;
-
- while (i < size)
- {
- if ((c = ser_getchar(port)) == EOF)
- return EOF;
- _buf[i++] = c;
- }
-
- return i;
-}
-
-
-/**
- * Write a string to serial.
- * \return 0 if OK, EOF in case of error.
- */
-int ser_print(struct Serial *port, const char *s)
-{
- while (*s)
- {
- if (ser_putchar(*s++, port) == EOF)
- return EOF;
- }
- return 0;
-}
-
-
-/**
- * \brief Write a buffer to serial.
- *
- * \return 0 if OK, EOF in case of error.
- *
- * \todo Optimize with fifo_pushblock()
- */
-int ser_write(struct Serial *port, const void *_buf, size_t len)
-{
- const char *buf = (const char *)_buf;
-
- while (len--)
- {
- if (ser_putchar(*buf++, port) == EOF)
- return EOF;
- }
- return 0;
-}
-
-
-#if CONFIG_PRINTF
-/**
- * Formatted write
- */
-int ser_printf(struct Serial *port, const char *format, ...)
-{
- va_list ap;
- int len;
-
- va_start(ap, format);
- len = _formatted_write(format, (void (*)(char, void *))ser_putchar, port, ap);
- va_end(ap);
-
- return len;
-}
-#endif /* CONFIG_PRINTF */
-
-
-#if CONFIG_SER_RXTIMEOUT != -1 || CONFIG_SER_TXTIMEOUT != -1
-void ser_settimeouts(struct Serial *port, mtime_t rxtimeout, mtime_t txtimeout)
-{
- port->rxtimeout = ms_to_ticks(rxtimeout);
- port->txtimeout = ms_to_ticks(txtimeout);
-}
-#endif /* CONFIG_SER_RXTIMEOUT || CONFIG_SER_TXTIMEOUT */
-
-#if CONFIG_SER_RXTIMEOUT != -1
-/**
- * Discard input to resynchronize with remote end.
- *
- * Discard incoming data until the port stops receiving
- * characters for at least \a delay milliseconds.
- *
- * \note Serial errors are reset before and after executing the purge.
- */
-void ser_resync(struct Serial *port, mtime_t delay)
-{
- mtime_t old_rxtimeout = ticks_to_ms(port->rxtimeout);
-
- ser_settimeouts(port, delay, ticks_to_ms(port->txtimeout));
- do
- {
- ser_setstatus(port, 0);
- ser_getchar(port);
- }
- while (!(ser_getstatus(port) & SERRF_RXTIMEOUT));
-
- /* Restore port to an usable status */
- ser_setstatus(port, 0);
- ser_settimeouts(port, old_rxtimeout, ticks_to_ms(port->txtimeout));
-}
-#endif /* CONFIG_SER_RXTIMEOUT */
-
-
-void ser_setbaudrate(struct Serial *port, unsigned long rate)
-{
- port->hw->table->setBaudrate(port->hw, rate);
-}
-
-
-void ser_setparity(struct Serial *port, int parity)
-{
- port->hw->table->setParity(port->hw, parity);
-}
-
-void ser_clearstatus(struct Serial *port)
-{
- ser_setstatus(port, 0);
-}
-
-/**
- * Flush both the RX and TX buffers.
- */
-void ser_purge(struct Serial *port)
-{
- fifo_flush_locked(&port->rxfifo);
- fifo_flush_locked(&port->txfifo);
-}
-
-
-/**
- * Wait until all pending output is completely
- * transmitted to the other end.
- *
- * \note The current implementation only checks the
- * software transmission queue. Any hardware
- * FIFOs are ignored.
- */
-void ser_drain(struct Serial *ser)
-{
- /*
- * Wait until the FIFO becomes empty, and then until the byte currently in
- * the hardware register gets shifted out.
- */
- while (!fifo_isempty(&ser->txfifo)
- || ser->hw->table->txSending(ser->hw))
- {
- #if CONFIG_KERNEL && CONFIG_KERN_SCHED
- /* Give up timeslice to other processes. */
- proc_switch();
- #endif
- wdt_reset();
- }
-}
-
-
-/**
- * Initialize a serial port.
- *
- * \param unit Serial unit to open. Possible values are architecture dependant.
- */
-struct Serial *ser_open(unsigned int unit)
-{
- struct Serial *port;
-
- ASSERT(unit < countof(ser_handles));
- port = &ser_handles[unit];
-
- ASSERT(!port->is_open);
- DB(port->is_open = true;)
-
- port->unit = unit;
-
- port->hw = ser_hw_getdesc(unit);
-
- /* Initialize circular buffers */
- ASSERT(port->hw->txbuffer);
- ASSERT(port->hw->rxbuffer);
- fifo_init(&port->txfifo, port->hw->txbuffer, port->hw->txbuffer_size);
- fifo_init(&port->rxfifo, port->hw->rxbuffer, port->hw->rxbuffer_size);
-
- port->hw->table->init(port->hw, port);
-
- /* Set default values */
-#if CONFIG_SER_RXTIMEOUT != -1 || CONFIG_SER_TXTIMEOUT != -1
- ser_settimeouts(port, CONFIG_SER_RXTIMEOUT, CONFIG_SER_TXTIMEOUT);
-#endif
-#if CONFIG_SER_DEFBAUDRATE
- ser_setbaudrate(port, CONFIG_SER_DEFBAUDRATE);
-#endif
-
- /* Clear error flags */
- ser_setstatus(port, 0);
-
- return port;
-}
-
-
-/**
- * Clean up serial port, disabling the associated hardware.
- */
-void ser_close(struct Serial *port)
-{
- ASSERT(port->is_open);
- DB(port->is_open = false;)
-
- // Wait until we finish sending everything
- ser_drain(port);
-
- port->hw->table->cleanup(port->hw);
- DB(port->hw = NULL;)
-
- /*
- * We purge the FIFO buffer only after the low-level cleanup, so that
- * we are sure that there are no more interrupts.
- */
- ser_purge(port);
-}