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linux/drivers/serial/68328serial.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2 
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

1615 lines
38 KiB
C
Raw Blame History

/* 68328serial.c: Serial port driver for 68328 microcontroller
*
* Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu>
* Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
* Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org>
* Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com>
* Copyright (C) 2002-2003 David McCullough <davidm@snapgear.com>
* Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
*
* VZ Support/Fixes Evan Stawnyczy <e@lineo.ca>
* Multiple UART support Daniel Potts <danielp@cse.unsw.edu.au>
* Power management support Daniel Potts <danielp@cse.unsw.edu.au>
* VZ Second Serial Port enable Phil Wilshire
* 2.4/2.5 port David McCullough
*/
#include <asm/dbg.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/config.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/console.h>
#include <linux/reboot.h>
#include <linux/keyboard.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/delay.h>
#include <asm/uaccess.h>
/* (es) */
/* note: perhaps we can murge these files, so that you can just
* define 1 of them, and they can sort that out for themselves
*/
#if defined(CONFIG_M68EZ328)
#include <asm/MC68EZ328.h>
#else
#if defined(CONFIG_M68VZ328)
#include <asm/MC68VZ328.h>
#else
#include <asm/MC68328.h>
#endif /* CONFIG_M68VZ328 */
#endif /* CONFIG_M68EZ328 */
#include "68328serial.h"
/* Turn off usage of real serial interrupt code, to "support" Copilot */
#ifdef CONFIG_XCOPILOT_BUGS
#undef USE_INTS
#else
#define USE_INTS
#endif
static struct m68k_serial m68k_soft[NR_PORTS];
struct m68k_serial *IRQ_ports[NR_IRQS];
static unsigned int uart_irqs[NR_PORTS] = UART_IRQ_DEFNS;
/* multiple ports are contiguous in memory */
m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
struct tty_struct m68k_ttys;
struct m68k_serial *m68k_consinfo = 0;
#define M68K_CLOCK (16667000) /* FIXME: 16MHz is likely wrong */
#ifdef CONFIG_CONSOLE
extern wait_queue_head_t keypress_wait;
#endif
struct tty_driver *serial_driver;
/* serial subtype definitions */
#define SERIAL_TYPE_NORMAL 1
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
/* Debugging... DEBUG_INTR is bad to use when one of the zs
* lines is your console ;(
*/
#undef SERIAL_DEBUG_INTR
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW
#define RS_ISR_PASS_LIMIT 256
#define _INLINE_ inline
static void change_speed(struct m68k_serial *info);
/*
* Setup for console. Argument comes from the boot command line.
*/
#if defined(CONFIG_M68EZ328ADS) || defined(CONFIG_ALMA_ANS) || defined(CONFIG_DRAGONIXVZ)
#define CONSOLE_BAUD_RATE 115200
#define DEFAULT_CBAUD B115200
#else
/* (es) */
/* note: this is messy, but it works, again, perhaps defined somewhere else?*/
#ifdef CONFIG_M68VZ328
#define CONSOLE_BAUD_RATE 19200
#define DEFAULT_CBAUD B19200
#endif
/* (/es) */
#endif
#ifndef CONSOLE_BAUD_RATE
#define CONSOLE_BAUD_RATE 9600
#define DEFAULT_CBAUD B9600
#endif
static int m68328_console_initted = 0;
static int m68328_console_baud = CONSOLE_BAUD_RATE;
static int m68328_console_cbaud = DEFAULT_CBAUD;
/*
* tmp_buf is used as a temporary buffer by serial_write. We need to
* lock it in case the memcpy_fromfs blocks while swapping in a page,
* and some other program tries to do a serial write at the same time.
* Since the lock will only come under contention when the system is
* swapping and available memory is low, it makes sense to share one
* buffer across all the serial ports, since it significantly saves
* memory if large numbers of serial ports are open.
*/
static unsigned char tmp_buf[SERIAL_XMIT_SIZE]; /* This is cheating */
DECLARE_MUTEX(tmp_buf_sem);
static inline int serial_paranoia_check(struct m68k_serial *info,
char *name, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
static const char *badmagic =
"Warning: bad magic number for serial struct %s in %s\n";
static const char *badinfo =
"Warning: null m68k_serial for %s in %s\n";
if (!info) {
printk(badinfo, name, routine);
return 1;
}
if (info->magic != SERIAL_MAGIC) {
printk(badmagic, name, routine);
return 1;
}
#endif
return 0;
}
/*
* This is used to figure out the divisor speeds and the timeouts
*/
static int baud_table[] = {
0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
9600, 19200, 38400, 57600, 115200, 0 };
#define BAUD_TABLE_SIZE (sizeof(baud_table)/sizeof(baud_table[0]))
/* Sets or clears DTR/RTS on the requested line */
static inline void m68k_rtsdtr(struct m68k_serial *ss, int set)
{
if (set) {
/* set the RTS/CTS line */
} else {
/* clear it */
}
return;
}
/* Utility routines */
static inline int get_baud(struct m68k_serial *ss)
{
unsigned long result = 115200;
unsigned short int baud = uart_addr[ss->line].ubaud;
if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400;
result >>= GET_FIELD(baud, UBAUD_DIVIDE);
return result;
}
/*
* ------------------------------------------------------------
* rs_stop() and rs_start()
*
* This routines are called before setting or resetting tty->stopped.
* They enable or disable transmitter interrupts, as necessary.
* ------------------------------------------------------------
*/
static void rs_stop(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_stop"))
return;
save_flags(flags); cli();
uart->ustcnt &= ~USTCNT_TXEN;
restore_flags(flags);
}
static void rs_put_char(char ch)
{
int flags, loops = 0;
save_flags(flags); cli();
while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
loops++;
udelay(5);
}
UTX_TXDATA = ch;
udelay(5);
restore_flags(flags);
}
static void rs_start(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_start"))
return;
save_flags(flags); cli();
if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
#ifdef USE_INTS
uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
#else
uart->ustcnt |= USTCNT_TXEN;
#endif
}
restore_flags(flags);
}
/* Drop into either the boot monitor or kadb upon receiving a break
* from keyboard/console input.
*/
static void batten_down_hatches(void)
{
/* Drop into the debugger */
}
static _INLINE_ void status_handle(struct m68k_serial *info, unsigned short status)
{
#if 0
if(status & DCD) {
if((info->tty->termios->c_cflag & CRTSCTS) &&
((info->curregs[3] & AUTO_ENAB)==0)) {
info->curregs[3] |= AUTO_ENAB;
info->pendregs[3] |= AUTO_ENAB;
write_zsreg(info->m68k_channel, 3, info->curregs[3]);
}
} else {
if((info->curregs[3] & AUTO_ENAB)) {
info->curregs[3] &= ~AUTO_ENAB;
info->pendregs[3] &= ~AUTO_ENAB;
write_zsreg(info->m68k_channel, 3, info->curregs[3]);
}
}
#endif
/* If this is console input and this is a
* 'break asserted' status change interrupt
* see if we can drop into the debugger
*/
if((status & URX_BREAK) && info->break_abort)
batten_down_hatches();
return;
}
static _INLINE_ void receive_chars(struct m68k_serial *info, struct pt_regs *regs, unsigned short rx)
{
struct tty_struct *tty = info->tty;
m68328_uart *uart = &uart_addr[info->line];
unsigned char ch;
/*
* This do { } while() loop will get ALL chars out of Rx FIFO
*/
#ifndef CONFIG_XCOPILOT_BUGS
do {
#endif
ch = GET_FIELD(rx, URX_RXDATA);
if(info->is_cons) {
if(URX_BREAK & rx) { /* whee, break received */
status_handle(info, rx);
return;
#ifdef CONFIG_MAGIC_SYSRQ
} else if (ch == 0x10) { /* ^P */
show_state();
show_free_areas();
show_buffers();
/* show_net_buffers(); */
return;
} else if (ch == 0x12) { /* ^R */
machine_restart(NULL);
return;
#endif /* CONFIG_MAGIC_SYSRQ */
}
/* It is a 'keyboard interrupt' ;-) */
#ifdef CONFIG_CONSOLE
wake_up(&keypress_wait);
#endif
}
if(!tty)
goto clear_and_exit;
/*
* Make sure that we do not overflow the buffer
*/
if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
schedule_work(&tty->flip.work);
return;
}
if(rx & URX_PARITY_ERROR) {
*tty->flip.flag_buf_ptr++ = TTY_PARITY;
status_handle(info, rx);
} else if(rx & URX_OVRUN) {
*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
status_handle(info, rx);
} else if(rx & URX_FRAME_ERROR) {
*tty->flip.flag_buf_ptr++ = TTY_FRAME;
status_handle(info, rx);
} else {
*tty->flip.flag_buf_ptr++ = 0; /* XXX */
}
*tty->flip.char_buf_ptr++ = ch;
tty->flip.count++;
#ifndef CONFIG_XCOPILOT_BUGS
} while((rx = uart->urx.w) & URX_DATA_READY);
#endif
schedule_work(&tty->flip.work);
clear_and_exit:
return;
}
static _INLINE_ void transmit_chars(struct m68k_serial *info)
{
m68328_uart *uart = &uart_addr[info->line];
if (info->x_char) {
/* Send next char */
uart->utx.b.txdata = info->x_char;
info->x_char = 0;
goto clear_and_return;
}
if((info->xmit_cnt <= 0) || info->tty->stopped) {
/* That's peculiar... TX ints off */
uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
goto clear_and_return;
}
/* Send char */
uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
if (info->xmit_cnt < WAKEUP_CHARS)
schedule_work(&info->tqueue);
if(info->xmit_cnt <= 0) {
/* All done for now... TX ints off */
uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
goto clear_and_return;
}
clear_and_return:
/* Clear interrupt (should be auto)*/
return;
}
/*
* This is the serial driver's generic interrupt routine
*/
irqreturn_t rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
{
struct m68k_serial * info;
m68328_uart *uart;
unsigned short rx;
unsigned short tx;
info = IRQ_ports[irq];
if(!info)
return IRQ_NONE;
uart = &uart_addr[info->line];
rx = uart->urx.w;
#ifdef USE_INTS
tx = uart->utx.w;
if (rx & URX_DATA_READY) receive_chars(info, regs, rx);
if (tx & UTX_TX_AVAIL) transmit_chars(info);
#else
receive_chars(info, regs, rx);
#endif
return IRQ_HANDLED;
}
static void do_softint(void *private)
{
struct m68k_serial *info = (struct m68k_serial *) private;
struct tty_struct *tty;
tty = info->tty;
if (!tty)
return;
#if 0
if (clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
tty_wakeup(tty);
}
#endif
}
/*
* This routine is called from the scheduler tqueue when the interrupt
* routine has signalled that a hangup has occurred. The path of
* hangup processing is:
*
* serial interrupt routine -> (scheduler tqueue) ->
* do_serial_hangup() -> tty->hangup() -> rs_hangup()
*
*/
static void do_serial_hangup(void *private)
{
struct m68k_serial *info = (struct m68k_serial *) private;
struct tty_struct *tty;
tty = info->tty;
if (!tty)
return;
tty_hangup(tty);
}
static int startup(struct m68k_serial * info)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (info->flags & S_INITIALIZED)
return 0;
if (!info->xmit_buf) {
info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL);
if (!info->xmit_buf)
return -ENOMEM;
}
save_flags(flags); cli();
/*
* Clear the FIFO buffers and disable them
* (they will be reenabled in change_speed())
*/
uart->ustcnt = USTCNT_UEN;
info->xmit_fifo_size = 1;
uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN;
(void)uart->urx.w;
/*
* Finally, enable sequencing and interrupts
*/
#ifdef USE_INTS
uart->ustcnt = USTCNT_UEN | USTCNT_RXEN |
USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK;
#else
uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK;
#endif
if (info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
/*
* and set the speed of the serial port
*/
change_speed(info);
info->flags |= S_INITIALIZED;
restore_flags(flags);
return 0;
}
/*
* This routine will shutdown a serial port; interrupts are disabled, and
* DTR is dropped if the hangup on close termio flag is on.
*/
static void shutdown(struct m68k_serial * info)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
uart->ustcnt = 0; /* All off! */
if (!(info->flags & S_INITIALIZED))
return;
save_flags(flags); cli(); /* Disable interrupts */
if (info->xmit_buf) {
free_page((unsigned long) info->xmit_buf);
info->xmit_buf = 0;
}
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
info->flags &= ~S_INITIALIZED;
restore_flags(flags);
}
struct {
int divisor, prescale;
}
#ifndef CONFIG_M68VZ328
hw_baud_table[18] = {
{0,0}, /* 0 */
{0,0}, /* 50 */
{0,0}, /* 75 */
{0,0}, /* 110 */
{0,0}, /* 134 */
{0,0}, /* 150 */
{0,0}, /* 200 */
{7,0x26}, /* 300 */
{6,0x26}, /* 600 */
{5,0x26}, /* 1200 */
{0,0}, /* 1800 */
{4,0x26}, /* 2400 */
{3,0x26}, /* 4800 */
{2,0x26}, /* 9600 */
{1,0x26}, /* 19200 */
{0,0x26}, /* 38400 */
{1,0x38}, /* 57600 */
{0,0x38}, /* 115200 */
};
#else
hw_baud_table[18] = {
{0,0}, /* 0 */
{0,0}, /* 50 */
{0,0}, /* 75 */
{0,0}, /* 110 */
{0,0}, /* 134 */
{0,0}, /* 150 */
{0,0}, /* 200 */
{0,0}, /* 300 */
{7,0x26}, /* 600 */
{6,0x26}, /* 1200 */
{0,0}, /* 1800 */
{5,0x26}, /* 2400 */
{4,0x26}, /* 4800 */
{3,0x26}, /* 9600 */
{2,0x26}, /* 19200 */
{1,0x26}, /* 38400 */
{0,0x26}, /* 57600 */
{1,0x38}, /* 115200 */
};
#endif
/* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
/*
* This routine is called to set the UART divisor registers to match
* the specified baud rate for a serial port.
*/
static void change_speed(struct m68k_serial *info)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned short port;
unsigned short ustcnt;
unsigned cflag;
int i;
if (!info->tty || !info->tty->termios)
return;
cflag = info->tty->termios->c_cflag;
if (!(port = info->port))
return;
ustcnt = uart->ustcnt;
uart->ustcnt = ustcnt & ~USTCNT_TXEN;
i = cflag & CBAUD;
if (i & CBAUDEX) {
i = (i & ~CBAUDEX) + B38400;
}
info->baud = baud_table[i];
uart->ubaud = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
if ((cflag & CSIZE) == CS8)
ustcnt |= USTCNT_8_7;
if (cflag & CSTOPB)
ustcnt |= USTCNT_STOP;
if (cflag & PARENB)
ustcnt |= USTCNT_PARITYEN;
if (cflag & PARODD)
ustcnt |= USTCNT_ODD_EVEN;
#ifdef CONFIG_SERIAL_68328_RTS_CTS
if (cflag & CRTSCTS) {
uart->utx.w &= ~ UTX_NOCTS;
} else {
uart->utx.w |= UTX_NOCTS;
}
#endif
ustcnt |= USTCNT_TXEN;
uart->ustcnt = ustcnt;
return;
}
/*
* Fair output driver allows a process to speak.
*/
static void rs_fair_output(void)
{
int left; /* Output no more than that */
unsigned long flags;
struct m68k_serial *info = &m68k_soft[0];
char c;
if (info == 0) return;
if (info->xmit_buf == 0) return;
save_flags(flags); cli();
left = info->xmit_cnt;
while (left != 0) {
c = info->xmit_buf[info->xmit_tail];
info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
restore_flags(flags);
rs_put_char(c);
save_flags(flags); cli();
left = min(info->xmit_cnt, left-1);
}
/* Last character is being transmitted now (hopefully). */
udelay(5);
restore_flags(flags);
return;
}
/*
* m68k_console_print is registered for printk.
*/
void console_print_68328(const char *p)
{
char c;
while((c=*(p++)) != 0) {
if(c == '\n')
rs_put_char('\r');
rs_put_char(c);
}
/* Comment this if you want to have a strict interrupt-driven output */
rs_fair_output();
return;
}
static void rs_set_ldisc(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_set_ldisc"))
return;
info->is_cons = (tty->termios->c_line == N_TTY);
printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
}
static void rs_flush_chars(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
return;
#ifndef USE_INTS
for(;;) {
#endif
/* Enable transmitter */
save_flags(flags); cli();
if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
!info->xmit_buf) {
restore_flags(flags);
return;
}
#ifdef USE_INTS
uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
#else
uart->ustcnt |= USTCNT_TXEN;
#endif
#ifdef USE_INTS
if (uart->utx.w & UTX_TX_AVAIL) {
#else
if (1) {
#endif
/* Send char */
uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
}
#ifndef USE_INTS
while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
}
#endif
restore_flags(flags);
}
extern void console_printn(const char * b, int count);
static int rs_write(struct tty_struct * tty,
const unsigned char *buf, int count)
{
int c, total = 0;
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_write"))
return 0;
if (!tty || !info->xmit_buf)
return 0;
save_flags(flags);
while (1) {
cli();
c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
SERIAL_XMIT_SIZE - info->xmit_head));
if (c <= 0)
break;
memcpy(info->xmit_buf + info->xmit_head, buf, c);
info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt += c;
restore_flags(flags);
buf += c;
count -= c;
total += c;
}
if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
/* Enable transmitter */
cli();
#ifndef USE_INTS
while(info->xmit_cnt) {
#endif
uart->ustcnt |= USTCNT_TXEN;
#ifdef USE_INTS
uart->ustcnt |= USTCNT_TX_INTR_MASK;
#else
while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
#endif
if (uart->utx.w & UTX_TX_AVAIL) {
uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
}
#ifndef USE_INTS
}
#endif
restore_flags(flags);
}
restore_flags(flags);
return total;
}
static int rs_write_room(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
int ret;
if (serial_paranoia_check(info, tty->name, "rs_write_room"))
return 0;
ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
if (ret < 0)
ret = 0;
return ret;
}
static int rs_chars_in_buffer(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
return 0;
return info->xmit_cnt;
}
static void rs_flush_buffer(struct tty_struct *tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
return;
cli();
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
sti();
tty_wakeup(tty);
}
/*
* ------------------------------------------------------------
* rs_throttle()
*
* This routine is called by the upper-layer tty layer to signal that
* incoming characters should be throttled.
* ------------------------------------------------------------
*/
static void rs_throttle(struct tty_struct * tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_throttle"))
return;
if (I_IXOFF(tty))
info->x_char = STOP_CHAR(tty);
/* Turn off RTS line (do this atomic) */
}
static void rs_unthrottle(struct tty_struct * tty)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
return;
if (I_IXOFF(tty)) {
if (info->x_char)
info->x_char = 0;
else
info->x_char = START_CHAR(tty);
}
/* Assert RTS line (do this atomic) */
}
/*
* ------------------------------------------------------------
* rs_ioctl() and friends
* ------------------------------------------------------------
*/
static int get_serial_info(struct m68k_serial * info,
struct serial_struct * retinfo)
{
struct serial_struct tmp;
if (!retinfo)
return -EFAULT;
memset(&tmp, 0, sizeof(tmp));
tmp.type = info->type;
tmp.line = info->line;
tmp.port = info->port;
tmp.irq = info->irq;
tmp.flags = info->flags;
tmp.baud_base = info->baud_base;
tmp.close_delay = info->close_delay;
tmp.closing_wait = info->closing_wait;
tmp.custom_divisor = info->custom_divisor;
copy_to_user(retinfo,&tmp,sizeof(*retinfo));
return 0;
}
static int set_serial_info(struct m68k_serial * info,
struct serial_struct * new_info)
{
struct serial_struct new_serial;
struct m68k_serial old_info;
int retval = 0;
if (!new_info)
return -EFAULT;
copy_from_user(&new_serial,new_info,sizeof(new_serial));
old_info = *info;
if (!capable(CAP_SYS_ADMIN)) {
if ((new_serial.baud_base != info->baud_base) ||
(new_serial.type != info->type) ||
(new_serial.close_delay != info->close_delay) ||
((new_serial.flags & ~S_USR_MASK) !=
(info->flags & ~S_USR_MASK)))
return -EPERM;
info->flags = ((info->flags & ~S_USR_MASK) |
(new_serial.flags & S_USR_MASK));
info->custom_divisor = new_serial.custom_divisor;
goto check_and_exit;
}
if (info->count > 1)
return -EBUSY;
/*
* OK, past this point, all the error checking has been done.
* At this point, we start making changes.....
*/
info->baud_base = new_serial.baud_base;
info->flags = ((info->flags & ~S_FLAGS) |
(new_serial.flags & S_FLAGS));
info->type = new_serial.type;
info->close_delay = new_serial.close_delay;
info->closing_wait = new_serial.closing_wait;
check_and_exit:
retval = startup(info);
return retval;
}
/*
* get_lsr_info - get line status register info
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
*/
static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
{
#ifdef CONFIG_SERIAL_68328_RTS_CTS
m68328_uart *uart = &uart_addr[info->line];
#endif
unsigned char status;
cli();
#ifdef CONFIG_SERIAL_68328_RTS_CTS
status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
#else
status = 0;
#endif
sti();
put_user(status,value);
return 0;
}
/*
* This routine sends a break character out the serial port.
*/
static void send_break( struct m68k_serial * info, int duration)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (!info->port)
return;
set_current_state(TASK_INTERRUPTIBLE);
save_flags(flags);
cli();
#ifdef USE_INTS
uart->utx.w |= UTX_SEND_BREAK;
schedule_timeout(duration);
uart->utx.w &= ~UTX_SEND_BREAK;
#endif
restore_flags(flags);
}
static int rs_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
int error;
struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
int retval;
if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
return -ENODEV;
if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
(cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
(cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
if (tty->flags & (1 << TTY_IO_ERROR))
return -EIO;
}
switch (cmd) {
case TCSBRK: /* SVID version: non-zero arg --> no break */
retval = tty_check_change(tty);
if (retval)
return retval;
tty_wait_until_sent(tty, 0);
if (!arg)
send_break(info, HZ/4); /* 1/4 second */
return 0;
case TCSBRKP: /* support for POSIX tcsendbreak() */
retval = tty_check_change(tty);
if (retval)
return retval;
tty_wait_until_sent(tty, 0);
send_break(info, arg ? arg*(HZ/10) : HZ/4);
return 0;
case TIOCGSOFTCAR:
error = put_user(C_CLOCAL(tty) ? 1 : 0,
(unsigned long *) arg);
if (error)
return error;
return 0;
case TIOCSSOFTCAR:
get_user(arg, (unsigned long *) arg);
tty->termios->c_cflag =
((tty->termios->c_cflag & ~CLOCAL) |
(arg ? CLOCAL : 0));
return 0;
case TIOCGSERIAL:
if (access_ok(VERIFY_WRITE, (void *) arg,
sizeof(struct serial_struct)))
return get_serial_info(info,
(struct serial_struct *) arg);
return -EFAULT;
case TIOCSSERIAL:
return set_serial_info(info,
(struct serial_struct *) arg);
case TIOCSERGETLSR: /* Get line status register */
if (access_ok(VERIFY_WRITE, (void *) arg,
sizeof(unsigned int));
return get_lsr_info(info, (unsigned int *) arg);
return -EFAULT;
case TIOCSERGSTRUCT:
if (!access_ok(VERIFY_WRITE, (void *) arg,
sizeof(struct m68k_serial)))
return -EFAULT;
copy_to_user((struct m68k_serial *) arg,
info, sizeof(struct m68k_serial));
return 0;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
if (tty->termios->c_cflag == old_termios->c_cflag)
return;
change_speed(info);
if ((old_termios->c_cflag & CRTSCTS) &&
!(tty->termios->c_cflag & CRTSCTS)) {
tty->hw_stopped = 0;
rs_start(tty);
}
}
/*
* ------------------------------------------------------------
* rs_close()
*
* This routine is called when the serial port gets closed. First, we
* wait for the last remaining data to be sent. Then, we unlink its
* S structure from the interrupt chain if necessary, and we free
* that IRQ if nothing is left in the chain.
* ------------------------------------------------------------
*/
static void rs_close(struct tty_struct *tty, struct file * filp)
{
struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
return;
save_flags(flags); cli();
if (tty_hung_up_p(filp)) {
restore_flags(flags);
return;
}
if ((tty->count == 1) && (info->count != 1)) {
/*
* Uh, oh. tty->count is 1, which means that the tty
* structure will be freed. Info->count should always
* be one in these conditions. If it's greater than
* one, we've got real problems, since it means the
* serial port won't be shutdown.
*/
printk("rs_close: bad serial port count; tty->count is 1, "
"info->count is %d\n", info->count);
info->count = 1;
}
if (--info->count < 0) {
printk("rs_close: bad serial port count for ttyS%d: %d\n",
info->line, info->count);
info->count = 0;
}
if (info->count) {
restore_flags(flags);
return;
}
info->flags |= S_CLOSING;
/*
* Now we wait for the transmit buffer to clear; and we notify
* the line discipline to only process XON/XOFF characters.
*/
tty->closing = 1;
if (info->closing_wait != S_CLOSING_WAIT_NONE)
tty_wait_until_sent(tty, info->closing_wait);
/*
* At this point we stop accepting input. To do this, we
* disable the receive line status interrupts, and tell the
* interrupt driver to stop checking the data ready bit in the
* line status register.
*/
uart->ustcnt &= ~USTCNT_RXEN;
uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
shutdown(info);
if (tty->driver->flush_buffer)
tty->driver->flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
info->event = 0;
info->tty = 0;
#warning "This is not and has never been valid so fix it"
#if 0
if (tty->ldisc.num != ldiscs[N_TTY].num) {
if (tty->ldisc.close)
(tty->ldisc.close)(tty);
tty->ldisc = ldiscs[N_TTY];
tty->termios->c_line = N_TTY;
if (tty->ldisc.open)
(tty->ldisc.open)(tty);
}
#endif
if (info->blocked_open) {
if (info->close_delay) {
msleep_interruptible(jiffies_to_msecs(info->close_delay));
}
wake_up_interruptible(&info->open_wait);
}
info->flags &= ~(S_NORMAL_ACTIVE|S_CLOSING);
wake_up_interruptible(&info->close_wait);
restore_flags(flags);
}
/*
* rs_hangup() --- called by tty_hangup() when a hangup is signaled.
*/
void rs_hangup(struct tty_struct *tty)
{
struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_hangup"))
return;
rs_flush_buffer(tty);
shutdown(info);
info->event = 0;
info->count = 0;
info->flags &= ~S_NORMAL_ACTIVE;
info->tty = 0;
wake_up_interruptible(&info->open_wait);
}
/*
* ------------------------------------------------------------
* rs_open() and friends
* ------------------------------------------------------------
*/
static int block_til_ready(struct tty_struct *tty, struct file * filp,
struct m68k_serial *info)
{
DECLARE_WAITQUEUE(wait, current);
int retval;
int do_clocal = 0;
/*
* If the device is in the middle of being closed, then block
* until it's done, and then try again.
*/
if (info->flags & S_CLOSING) {
interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
if (info->flags & S_HUP_NOTIFY)
return -EAGAIN;
else
return -ERESTARTSYS;
#else
return -EAGAIN;
#endif
}
/*
* If non-blocking mode is set, or the port is not enabled,
* then make the check up front and then exit.
*/
if ((filp->f_flags & O_NONBLOCK) ||
(tty->flags & (1 << TTY_IO_ERROR))) {
info->flags |= S_NORMAL_ACTIVE;
return 0;
}
if (tty->termios->c_cflag & CLOCAL)
do_clocal = 1;
/*
* Block waiting for the carrier detect and the line to become
* free (i.e., not in use by the callout). While we are in
* this loop, info->count is dropped by one, so that
* rs_close() knows when to free things. We restore it upon
* exit, either normal or abnormal.
*/
retval = 0;
add_wait_queue(&info->open_wait, &wait);
info->count--;
info->blocked_open++;
while (1) {
cli();
m68k_rtsdtr(info, 1);
sti();
current->state = TASK_INTERRUPTIBLE;
if (tty_hung_up_p(filp) ||
!(info->flags & S_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
if (info->flags & S_HUP_NOTIFY)
retval = -EAGAIN;
else
retval = -ERESTARTSYS;
#else
retval = -EAGAIN;
#endif
break;
}
if (!(info->flags & S_CLOSING) && do_clocal)
break;
if (signal_pending(current)) {
retval = -ERESTARTSYS;
break;
}
schedule();
}
current->state = TASK_RUNNING;
remove_wait_queue(&info->open_wait, &wait);
if (!tty_hung_up_p(filp))
info->count++;
info->blocked_open--;
if (retval)
return retval;
info->flags |= S_NORMAL_ACTIVE;
return 0;
}
/*
* This routine is called whenever a serial port is opened. It
* enables interrupts for a serial port, linking in its S structure into
* the IRQ chain. It also performs the serial-specific
* initialization for the tty structure.
*/
int rs_open(struct tty_struct *tty, struct file * filp)
{
struct m68k_serial *info;
int retval, line;
line = tty->index;
if (line >= NR_PORTS || line < 0) /* we have exactly one */
return -ENODEV;
info = &m68k_soft[line];
if (serial_paranoia_check(info, tty->name, "rs_open"))
return -ENODEV;
info->count++;
tty->driver_data = info;
info->tty = tty;
/*
* Start up serial port
*/
retval = startup(info);
if (retval)
return retval;
return block_til_ready(tty, filp, info);
}
/* Finally, routines used to initialize the serial driver. */
static void show_serial_version(void)
{
printk("MC68328 serial driver version 1.00\n");
}
#ifdef CONFIG_PM
/* Serial Power management
* The console (currently fixed at line 0) is a special case for power
* management because the kernel is so chatty. The console will be
* explicitly disabled my our power manager as the last minute, so we won't
* mess with it here.
*/
static struct pm_dev *serial_pm[NR_PORTS];
static int serial_pm_callback(struct pm_dev *dev, pm_request_t request, void *data)
{
struct m68k_serial *info = (struct m68k_serial *)dev->data;
if(info == NULL)
return -1;
/* special case for line 0 - pm restores it */
if(info->line == 0)
return 0;
switch (request) {
case PM_SUSPEND:
shutdown(info);
break;
case PM_RESUME:
startup(info);
break;
}
return 0;
}
void shutdown_console(void)
{
struct m68k_serial *info = &m68k_soft[0];
/* HACK: wait a bit for any pending printk's to be dumped */
{
int i = 10000;
while(i--);
}
shutdown(info);
}
void startup_console(void)
{
struct m68k_serial *info = &m68k_soft[0];
startup(info);
}
#endif
static struct tty_operations rs_ops = {
.open = rs_open,
.close = rs_close,
.write = rs_write,
.flush_chars = rs_flush_chars,
.write_room = rs_write_room,
.chars_in_buffer = rs_chars_in_buffer,
.flush_buffer = rs_flush_buffer,
.ioctl = rs_ioctl,
.throttle = rs_throttle,
.unthrottle = rs_unthrottle,
.set_termios = rs_set_termios,
.stop = rs_stop,
.start = rs_start,
.hangup = rs_hangup,
.set_ldisc = rs_set_ldisc,
};
/* rs_init inits the driver */
static int __init
rs68328_init(void)
{
int flags, i;
struct m68k_serial *info;
serial_driver = alloc_tty_driver(NR_PORTS);
if (!serial_driver)
return -ENOMEM;
show_serial_version();
/* Initialize the tty_driver structure */
/* SPARC: Not all of this is exactly right for us. */
serial_driver->name = "ttyS";
serial_driver->major = TTY_MAJOR;
serial_driver->minor_start = 64;
serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
serial_driver->subtype = SERIAL_TYPE_NORMAL;
serial_driver->init_termios = tty_std_termios;
serial_driver->init_termios.c_cflag =
m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL;
serial_driver->flags = TTY_DRIVER_REAL_RAW;
tty_set_operations(serial_driver, &rs_ops);
if (tty_register_driver(serial_driver)) {
put_tty_driver(serial_driver);
printk(KERN_ERR "Couldn't register serial driver\n");
return -ENOMEM;
}
save_flags(flags); cli();
for(i=0;i<NR_PORTS;i++) {
info = &m68k_soft[i];
info->magic = SERIAL_MAGIC;
info->port = (int) &uart_addr[i];
info->tty = 0;
info->irq = uart_irqs[i];
info->custom_divisor = 16;
info->close_delay = 50;
info->closing_wait = 3000;
info->x_char = 0;
info->event = 0;
info->count = 0;
info->blocked_open = 0;
INIT_WORK(&info->tqueue, do_softint, info);
INIT_WORK(&info->tqueue_hangup, do_serial_hangup, info);
init_waitqueue_head(&info->open_wait);
init_waitqueue_head(&info->close_wait);
info->line = i;
info->is_cons = 1; /* Means shortcuts work */
printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line,
info->port, info->irq);
printk(" is a builtin MC68328 UART\n");
IRQ_ports[info->irq] = info; /* waste of space */
#ifdef CONFIG_M68VZ328
if (i > 0 )
PJSEL &= 0xCF; /* PSW enable second port output */
#endif
if (request_irq(uart_irqs[i],
rs_interrupt,
IRQ_FLG_STD,
"M68328_UART", NULL))
panic("Unable to attach 68328 serial interrupt\n");
#ifdef CONFIG_PM
serial_pm[i] = pm_register(PM_SYS_DEV, PM_SYS_COM, serial_pm_callback);
if (serial_pm[i])
serial_pm[i]->data = info;
#endif
}
restore_flags(flags);
return 0;
}
/*
* register_serial and unregister_serial allows for serial ports to be
* configured at run-time, to support PCMCIA modems.
*/
/* SPARC: Unused at this time, just here to make things link. */
int register_serial(struct serial_struct *req)
{
return -1;
}
void unregister_serial(int line)
{
return;
}
module_init(rs68328_init);
static void m68328_set_baud(void)
{
unsigned short ustcnt;
int i;
ustcnt = USTCNT;
USTCNT = ustcnt & ~USTCNT_TXEN;
again:
for (i = 0; i < sizeof(baud_table) / sizeof(baud_table[0]); i++)
if (baud_table[i] == m68328_console_baud)
break;
if (i >= sizeof(baud_table) / sizeof(baud_table[0])) {
m68328_console_baud = 9600;
goto again;
}
UBAUD = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
ustcnt |= USTCNT_8_7;
ustcnt |= USTCNT_TXEN;
USTCNT = ustcnt;
m68328_console_initted = 1;
return;
}
int m68328_console_setup(struct console *cp, char *arg)
{
int i, n = CONSOLE_BAUD_RATE;
if (!cp)
return(-1);
if (arg)
n = simple_strtoul(arg,NULL,0);
for (i = 0; i < BAUD_TABLE_SIZE; i++)
if (baud_table[i] == n)
break;
if (i < BAUD_TABLE_SIZE) {
m68328_console_baud = n;
m68328_console_cbaud = 0;
if (i > 15) {
m68328_console_cbaud |= CBAUDEX;
i -= 15;
}
m68328_console_cbaud |= i;
}
m68328_set_baud(); /* make sure baud rate changes */
return(0);
}
static struct tty_driver *m68328_console_device(struct console *c, int *index)
{
*index = c->index;
return serial_driver;
}
void m68328_console_write (struct console *co, const char *str,
unsigned int count)
{
if (!m68328_console_initted)
m68328_set_baud();
while (count--) {
if (*str == '\n')
rs_put_char('\r');
rs_put_char( *str++ );
}
}
static struct console m68328_driver = {
.name = "ttyS",
.write = m68328_console_write,
.device = m68328_console_device,
.setup = m68328_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
};
static int __init m68328_console_init(void)
{
register_console(&m68328_driver);
return 0;
}
console_initcall(m68328_console_init);
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