-/**
- * \file
- * <!--
- * Copyright 2003, 2004, 2006 Develer S.r.l. (http://www.develer.com/)
- * Copyright 2000 Bernardo Innocenti <bernie@codewiz.org>
- * This file is part of DevLib - See README.devlib for information.
- * -->
- *
- * \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>
- */
-
-/*#*
- *#* $Log$
- *#* Revision 1.32 2006/11/17 17:03:58 batt
- *#* Implement ser_setstatus and ser_getstatus as functions to avoid race conditions.
- *#*
- *#* Revision 1.31 2006/07/21 10:58:00 batt
- *#* Use timer_clock() instead of obsolete timer_ticks().
- *#*
- *#* Revision 1.30 2006/07/19 12:56:26 bernie
- *#* Convert to new Doxygen style.
- *#*
- *#* Revision 1.29 2006/05/18 00:39:30 bernie
- *#* ser_open(): Document a bit more.
- *#*
- *#* Revision 1.28 2006/02/17 22:23:06 bernie
- *#* Update POSIX serial emulator.
- *#*
- *#* Revision 1.27 2005/11/27 23:33:40 bernie
- *#* Use appconfig.h instead of cfg/config.h.
- *#*
- *#* Revision 1.26 2005/11/04 16:20:02 bernie
- *#* Fix reference to README.devlib in header.
- *#*
- *#* Revision 1.25 2005/04/11 19:10:27 bernie
- *#* Include top-level headers from cfg/ subdir.
- *#*
- *#* Revision 1.24 2005/01/21 20:13:15 aleph
- *#* Fix drain at ser_close()
- *#*
- *#* Revision 1.23 2005/01/14 00:47:07 aleph
- *#* ser_drain(): Wait for hw transmission complete.
- *#*
- *#* Revision 1.22 2004/12/08 08:56:14 bernie
- *#* Rename time_t to mtime_t.
- *#*
- *#* Revision 1.21 2004/11/16 18:10:13 bernie
- *#* Add sanity checks for missing configuration parameters.
- *#*
- *#* Revision 1.20 2004/10/19 11:48:00 bernie
- *#* Remove unused variable.
- *#*
- *#* Revision 1.19 2004/10/19 08:14:13 bernie
- *#* Fix a few longstanding bugs wrt status handling (made by rasky on scfirm).
- *#*
- *#* Revision 1.18 2004/09/20 03:31:15 bernie
- *#* Sanitize for C++.
- *#*
- *#* Revision 1.17 2004/09/14 21:06:07 bernie
- *#* Use debug.h instead of kdebug.h; Spelling fixes.
- *#*
- *#* Revision 1.16 2004/09/06 21:40:50 bernie
- *#* Move buffer handling in chip-specific driver.
- *#*
- *#* Revision 1.15 2004/08/25 14:12:08 rasky
- *#* Aggiornato il comment block dei log RCS
- *#*
- *#* Revision 1.14 2004/08/24 16:22:57 bernie
- *#* Thinkos; Doxygen fixes
- *#*
- *#* Revision 1.13 2004/08/24 16:20:48 bernie
- *#* ser_read(): Make buffer argument void *#* for consistency with ANSI C and ser_write()
- *#*
- *#* Revision 1.12 2004/08/24 13:49:39 bernie
- *#* Fix thinko.
- *#*
- *#* Revision 1.11 2004/08/15 05:32:22 bernie
- *#* ser_resync(): New function.
- *#*
- *#* Revision 1.10 2004/08/10 06:29:50 bernie
- *#* Rename timer_gettick() to timer_ticks().
- *#*
- *#* Revision 1.9 2004/08/08 06:06:20 bernie
- *#* Use new-style CONFIG_ idiom; Fix module-wide documentation.
- *#*
- *#* Revision 1.8 2004/07/29 22:57:09 bernie
- *#* ser_drain(): New function; Make Serial::is_open a debug-only feature; Switch to new-style CONFIG_* macros.
- *#*
- *#* Revision 1.7 2004/07/18 21:49:03 bernie
- *#* Make CONFIG_SER_DEFBAUDRATE optional.
- *#*
- *#* Revision 1.6 2004/06/07 15:56:28 aleph
- *#* Remove cast-as-lvalue extension abuse
- *#*
- *#* Revision 1.5 2004/06/06 16:41:44 bernie
- *#* ser_putchar(): Use fifo_push_locked() to fix potential race on 8bit processors.
- *#*
- *#* Revision 1.4 2004/06/03 11:27:09 bernie
- *#* Add dual-license information.
- *#*
- *#* Revision 1.3 2004/06/02 21:35:24 aleph
- *#* Serial enhancements: interruptible receive handler and 8 bit serial status for AVR; remove volatile attribute to FIFOBuffer, useless for new fifobuf routens
- *#*
- *#* Revision 1.2 2004/05/23 18:21:53 bernie
- *#* Trim CVS logs and cleanup header info.
- *#*
- *#*/
-
-#include "ser.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
- {
-#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)
- {
- 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
- {
-#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)
- {
- port->status |= SERRF_RXTIMEOUT;
- return EOF;
- }
-#endif /* CONFIG_SER_RXTIMEOUT */
- }
- while (fifo_isempty_locked(&port->rxfifo) && (port->status & SERRF_RX) == 0);
- }
-
- /*
- * Get a byte from the FIFO (avoiding sign-extension),
- * re-enable RTS, then return result.
- */
- if (port->status & 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);
-}
-
-
-/**
- * Flush both the RX and TX buffers.
- */
-void ser_purge(struct Serial *port)
-{
- fifo_flush_locked(&port->rxfifo);
- fifo_flush_locked(&port->txfifo);
-}
-
-/**
- * Get status of port \c port.
- */
-serstatus_t ser_getstatus(struct Serial *port)
-{
- serstatus_t status;
- ATOMIC(status = port->status);
-
- return status;
-}
-
-
-/**
- * Set new \c port status.
- */
-void ser_setstatus(struct Serial *port, serstatus_t status)
-{
- ATOMIC(port->status = status);
-}
-
-
-/**
- * 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
- }
-}
-
-
-/**
- * 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);
-}