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OpenCloudOS-Kernel/drivers/tty/serial/68328serial.c

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/* 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/serial.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/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 */
/* Turn off usage of real serial interrupt code, to "support" Copilot */
#ifdef CONFIG_XCOPILOT_BUGS
#undef USE_INTS
#else
#define USE_INTS
#endif
/*
* I believe this is the optimal setting that reduces the number of interrupts.
* At high speeds the output might become a little "bursted" (use USTCNT_TXHE
* if that bothers you), but in most cases it will not, since we try to
* transmit characters every time rs_interrupt is called. Thus, quite often
* you'll see that a receive interrupt occures before the transmit one.
* -- Vladimir Gurevich
*/
#define USTCNT_TX_INTR_MASK (USTCNT_TXEE)
/*
* 68328 and 68EZ328 UARTS are a little bit different. EZ328 has special
* "Old data interrupt" which occures whenever the data stay in the FIFO
* longer than 30 bits time. This allows us to use FIFO without compromising
* latency. '328 does not have this feature and without the real 328-based
* board I would assume that RXRE is the safest setting.
*
* For EZ328 I use RXHE (Half empty) interrupt to reduce the number of
* interrupts. RXFE (receive queue full) causes the system to lose data
* at least at 115200 baud
*
* If your board is busy doing other stuff, you might consider to use
* RXRE (data ready intrrupt) instead.
*
* The other option is to make these INTR masks run-time configurable, so
* that people can dynamically adapt them according to the current usage.
* -- Vladimir Gurevich
*/
/* (es) */
#if defined(CONFIG_M68EZ328) || defined(CONFIG_M68VZ328)
#define USTCNT_RX_INTR_MASK (USTCNT_RXHE | USTCNT_ODEN)
#elif defined(CONFIG_M68328)
#define USTCNT_RX_INTR_MASK (USTCNT_RXRE)
#else
#error Please, define the Rx interrupt events for your CPU
#endif
/* (/es) */
/*
* This is our internal structure for each serial port's state.
*/
struct m68k_serial {
struct tty_port tport;
char is_cons; /* Is this our console. */
int magic;
int baud_base;
int port;
int irq;
int type; /* UART type */
int custom_divisor;
int x_char; /* xon/xoff character */
int line;
unsigned char *xmit_buf;
int xmit_head;
int xmit_tail;
int xmit_cnt;
};
#define SERIAL_MAGIC 0x5301
/*
* Define the number of ports supported and their irqs.
*/
#define NR_PORTS 1
static struct m68k_serial m68k_soft[NR_PORTS];
static unsigned int uart_irqs[NR_PORTS] = { UART_IRQ_NUM };
/* multiple ports are contiguous in memory */
m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
struct tty_driver *serial_driver;
static void change_speed(struct m68k_serial *info, struct tty_struct *tty);
/*
* 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 };
/* 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)
{
unsigned long flags;
int 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);
}
static void receive_chars(struct m68k_serial *info, unsigned short rx)
{
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 */
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 */
}
}
flag = TTY_NORMAL;
if (rx & URX_PARITY_ERROR)
flag = TTY_PARITY;
else if (rx & URX_OVRUN)
flag = TTY_OVERRUN;
else if (rx & URX_FRAME_ERROR)
flag = TTY_FRAME;
tty_insert_flip_char(&info->tport, ch, flag);
#ifndef CONFIG_XCOPILOT_BUGS
} while((rx = uart->urx.w) & URX_DATA_READY);
#endif
tty_schedule_flip(&info->tport);
}
static void transmit_chars(struct m68k_serial *info, struct tty_struct *tty)
{
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) || !tty || 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;
struct tty_struct *tty = tty_port_tty_get(&info->tport);
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, tty);
#else
receive_chars(info, rx);
#endif
tty_kref_put(tty);
return IRQ_HANDLED;
}
static int startup(struct m68k_serial *info, struct tty_struct *tty)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (info->tport.flags & ASYNC_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;
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 (tty)
clear_bit(TTY_IO_ERROR, &tty->flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
/*
* and set the speed of the serial port
*/
change_speed(info, tty);
info->tport.flags |= ASYNC_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, struct tty_struct *tty)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
uart->ustcnt = 0; /* All off! */
if (!(info->tport.flags & ASYNC_INITIALIZED))
return;
local_irq_save(flags);
if (info->xmit_buf) {
free_page((unsigned long) info->xmit_buf);
info->xmit_buf = 0;
}
if (tty)
set_bit(TTY_IO_ERROR, &tty->flags);
info->tport.flags &= ~ASYNC_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, struct tty_struct *tty)
{
m68328_uart *uart = &uart_addr[info->line];
unsigned short port;
unsigned short ustcnt;
unsigned cflag;
int i;
cflag = 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;
}
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 || !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) {
/* 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->tport.flags;
tmp.baud_base = info->baud_base;
tmp.close_delay = info->tport.close_delay;
tmp.closing_wait = info->tport.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 tty_struct *tty,
struct serial_struct * new_info)
{
struct tty_port *port = &info->tport;
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 != port->close_delay) ||
((new_serial.flags & ~ASYNC_USR_MASK) !=
(port->flags & ~ASYNC_USR_MASK)))
return -EPERM;
port->flags = ((port->flags & ~ASYNC_USR_MASK) |
(new_serial.flags & ASYNC_USR_MASK));
info->custom_divisor = new_serial.custom_divisor;
goto check_and_exit;
}
if (port->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;
port->flags = ((port->flags & ~ASYNC_FLAGS) |
(new_serial.flags & ASYNC_FLAGS));
info->type = new_serial.type;
port->close_delay = new_serial.close_delay;
port->closing_wait = new_serial.closing_wait;
check_and_exit:
retval = startup(info, tty);
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, tty,
(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, tty);
if ((old_termios->c_cflag & CRTSCTS) &&
!(tty->termios.c_cflag & CRTSCTS))
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;
struct tty_port *port = &info->tport;
m68328_uart *uart = &uart_addr[info->line];
unsigned long flags;
if (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) && (port->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, "
"port->count is %d\n", port->count);
port->count = 1;
}
if (--port->count < 0) {
printk("rs_close: bad serial port count for ttyS%d: %d\n",
info->line, port->count);
port->count = 0;
}
if (port->count) {
local_irq_restore(flags);
return;
}
port->flags |= ASYNC_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 (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
tty_wait_until_sent(tty, port->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, tty);
rs_flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
tty_port_tty_set(&info->tport, 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 (port->blocked_open) {
if (port->close_delay)
msleep_interruptible(jiffies_to_msecs(port->close_delay));
wake_up_interruptible(&port->open_wait);
}
port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
wake_up_interruptible(&port->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, tty);
info->tport.count = 0;
info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
tty_port_tty_set(&info->tport, NULL);
wake_up_interruptible(&info->tport.open_wait);
}
/*
* 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->tport.count++;
tty->driver_data = info;
tty_port_tty_set(&info->tport, tty);
/*
* Start up serial port
*/
retval = startup(info, tty);
if (retval)
return retval;
return tty_port_block_til_ready(&info->tport, tty, filp);
}
/* 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,
};
static const struct tty_port_operations rs_port_ops = {
};
/* rs_init inits the driver */
static int __init
rs68328_init(void)
{
unsigned long flags;
int 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);
local_irq_save(flags);
for(i=0;i<NR_PORTS;i++) {
info = &m68k_soft[i];
tty_port_init(&info->tport);
info->tport.ops = &rs_port_ops;
info->magic = SERIAL_MAGIC;
info->port = (int) &uart_addr[i];
info->irq = uart_irqs[i];
info->custom_divisor = 16;
info->x_char = 0;
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");
tty_port_link_device(&info->tport, serial_driver, i);
}
local_irq_restore(flags);
if (tty_register_driver(serial_driver)) {
put_tty_driver(serial_driver);
for (i = 0; i < NR_PORTS; i++)
tty_port_destroy(&m68k_soft[i].tport);
printk(KERN_ERR "Couldn't register serial driver\n");
return -ENOMEM;
}
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);
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