Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-23 19:31:53 +00:00
Code Issues Packages Projects Releases Wiki Activity
dfe42443ea
linux/drivers/tty/serial/68328serial.c
Jiri Slaby 410235fd4d TTY: remove unneeded tty->index checks 
Checking if tty->index is in bounds is not needed. The tty has the
index set in the initial open. This is done in get_tty_driver. And it
can be only in interval <0,driver->num).

So remove the tests which check exactly this interval. Some are
left untouched as they check against the current backing device count.
(Leaving apart that the check is racy in most of the cases.)

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 11:42:21 -08:00

1409 lines
33 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/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 <linux/gfp.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.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];
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 */
struct tty_driver *serial_driver;
/* 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
static void change_speed(struct m68k_serial *info);
/*
* Setup for console. Argument comes from the boot command line.
*/
/* 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
#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;
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 };
/* 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;
local_irq_save(flags);
uart->ustcnt &= ~USTCNT_TXEN;
local_irq_restore(flags);
}
static int rs_put_char(char ch)
{
int flags, loops = 0;
local_irq_save(flags);
while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
loops++;
udelay(5);
}
UTX_TXDATA = ch;
udelay(5);
local_irq_restore(flags);
return 1;
}
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;
local_irq_save(flags);
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
}
local_irq_restore(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 void status_handle(struct m68k_serial *info, unsigned short status)
{
/* 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 void receive_chars(struct m68k_serial *info, unsigned short rx)
{
struct tty_struct *tty = info->tty;
m68328_uart *uart = &uart_addr[info->line];
unsigned char ch, flag;
/*
* 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(0);
show_buffers();
/* show_net_buffers(); */
return;
} else if (ch == 0x12) { /* ^R */
emergency_restart();
return;
#endif /* CONFIG_MAGIC_SYSRQ */
}
}
if(!tty)
goto clear_and_exit;
flag = TTY_NORMAL;
if(rx & URX_PARITY_ERROR) {
flag = TTY_PARITY;
status_handle(info, rx);
} else if(rx & URX_OVRUN) {
flag = TTY_OVERRUN;
status_handle(info, rx);
} else if(rx & URX_FRAME_ERROR) {
flag = TTY_FRAME;
status_handle(info, rx);
}
tty_insert_flip_char(tty, ch, flag);
#ifndef CONFIG_XCOPILOT_BUGS
} while((rx = uart->urx.w) & URX_DATA_READY);
#endif
tty_schedule_flip(tty);
clear_and_exit:
return;
}
static 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 <= 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 m68k_serial *info = dev_id;
m68328_uart *uart;
unsigned short rx;
unsigned short tx;
uart = &uart_addr[info->line];
rx = uart->urx.w;
#ifdef USE_INTS
tx = uart->utx.w;
if (rx & URX_DATA_READY) receive_chars(info, rx);
if (tx & UTX_TX_AVAIL) transmit_chars(info);
#else
receive_chars(info, rx);
#endif
return IRQ_HANDLED;
}
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;
}
local_irq_save(flags);
/*
* 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;
local_irq_restore(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;
local_irq_save(flags);
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;
local_irq_restore(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;
local_irq_save(flags);
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--;
local_irq_restore(flags);
rs_put_char(c);
local_irq_save(flags);
left = min(info->xmit_cnt, left-1);
}
/* Last character is being transmitted now (hopefully). */
udelay(5);
local_irq_restore(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 */
local_irq_save(flags);
if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
!info->xmit_buf) {
local_irq_restore(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
local_irq_restore(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;
local_save_flags(flags);
while (1) {
local_irq_disable();
c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
SERIAL_XMIT_SIZE - info->xmit_head));
local_irq_restore(flags);
if (c <= 0)
break;
memcpy(info->xmit_buf + info->xmit_head, buf, c);
local_irq_disable();
info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt += c;
local_irq_restore(flags);
buf += c;
count -= c;
total += c;
}
if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
/* Enable transmitter */
local_irq_disable();
#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
local_irq_restore(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;
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
return;
local_irq_save(flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
local_irq_restore(flags);
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;
if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
return -EFAULT;
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;
if (copy_from_user(&new_serial, new_info, sizeof(new_serial)))
return -EFAULT;
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;
unsigned long flags;
local_irq_save(flags);
#ifdef CONFIG_SERIAL_68328_RTS_CTS
status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
#else
status = 0;
#endif
local_irq_restore(flags);
return put_user(status, value);
}
/*
* This routine sends a break character out the serial port.
*/
static void send_break(struct m68k_serial * info, unsigned int duration)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (!info->port)
return;
local_irq_save(flags);
#ifdef USE_INTS
uart->utx.w |= UTX_SEND_BREAK;
msleep_interruptible(duration);
uart->utx.w &= ~UTX_SEND_BREAK;
#endif
local_irq_restore(flags);
}
static int rs_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
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, 250); /* 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*(100) : 250);
return 0;
case TIOCGSERIAL:
return get_serial_info(info,
(struct serial_struct *) arg);
case TIOCSSERIAL:
return set_serial_info(info,
(struct serial_struct *) arg);
case TIOCSERGETLSR: /* Get line status register */
return get_lsr_info(info, (unsigned int *) arg);
case TIOCSERGSTRUCT:
if (copy_to_user((struct m68k_serial *) arg,
info, sizeof(struct m68k_serial)))
return -EFAULT;
return 0;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
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;
local_irq_save(flags);
if (tty_hung_up_p(filp)) {
local_irq_restore(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) {
local_irq_restore(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);
rs_flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
info->event = 0;
info->tty = NULL;
#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);
local_irq_restore(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 = NULL;
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) {
local_irq_disable();
m68k_rtsdtr(info, 1);
local_irq_enable();
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;
}
tty_unlock();
schedule();
tty_lock();
}
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;
info = &m68k_soft[tty->index];
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");
}
static const 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;
}
local_irq_save(flags);
for(i=0;i<NR_PORTS;i++) {
info = &m68k_soft[i];
info->magic = SERIAL_MAGIC;
info->port = (int) &uart_addr[i];
info->tty = NULL;
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_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");
#ifdef CONFIG_M68VZ328
if (i > 0 )
PJSEL &= 0xCF; /* PSW enable second port output */
#endif
if (request_irq(uart_irqs[i],
rs_interrupt,
0,
"M68328_UART", info))
panic("Unable to attach 68328 serial interrupt\n");
}
local_irq_restore(flags);
return 0;
}
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 < ARRAY_SIZE(baud_table); i++)
if (baud_table[i] == m68328_console_baud)
break;
if (i >= ARRAY_SIZE(baud_table)) {
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 < ARRAY_SIZE(baud_table); i++)
if (baud_table[i] == n)
break;
if (i < ARRAY_SIZE(baud_table)) {
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);
Reference in New Issue View Git Blame Copy Permalink