1 /* 68328serial.c: Serial port driver for 68328 microcontroller
3 * Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu>
4 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
5 * Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org>
6 * Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com>
7 * Copyright (C) 2002-2003 David McCullough <davidm@snapgear.com>
8 * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
10 * VZ Support/Fixes Evan Stawnyczy <e@lineo.ca>
11 * Multiple UART support Daniel Potts <danielp@cse.unsw.edu.au>
12 * Power management support Daniel Potts <danielp@cse.unsw.edu.au>
13 * VZ Second Serial Port enable Phil Wilshire
14 * 2.4/2.5 port David McCullough
18 #include <linux/module.h>
19 #include <linux/errno.h>
20 #include <linux/serial.h>
21 #include <linux/signal.h>
22 #include <linux/sched.h>
23 #include <linux/timer.h>
24 #include <linux/interrupt.h>
25 #include <linux/tty.h>
26 #include <linux/tty_flip.h>
27 #include <linux/major.h>
28 #include <linux/string.h>
29 #include <linux/fcntl.h>
31 #include <linux/kernel.h>
32 #include <linux/console.h>
33 #include <linux/reboot.h>
34 #include <linux/keyboard.h>
35 #include <linux/init.h>
37 #include <linux/bitops.h>
38 #include <linux/delay.h>
39 #include <linux/gfp.h>
43 #include <asm/delay.h>
44 #include <asm/uaccess.h>
47 /* note: perhaps we can murge these files, so that you can just
48 * define 1 of them, and they can sort that out for themselves
50 #if defined(CONFIG_M68EZ328)
51 #include <asm/MC68EZ328.h>
53 #if defined(CONFIG_M68VZ328)
54 #include <asm/MC68VZ328.h>
56 #include <asm/MC68328.h>
57 #endif /* CONFIG_M68VZ328 */
58 #endif /* CONFIG_M68EZ328 */
60 /* Turn off usage of real serial interrupt code, to "support" Copilot */
61 #ifdef CONFIG_XCOPILOT_BUGS
68 * I believe this is the optimal setting that reduces the number of interrupts.
69 * At high speeds the output might become a little "bursted" (use USTCNT_TXHE
70 * if that bothers you), but in most cases it will not, since we try to
71 * transmit characters every time rs_interrupt is called. Thus, quite often
72 * you'll see that a receive interrupt occures before the transmit one.
73 * -- Vladimir Gurevich
75 #define USTCNT_TX_INTR_MASK (USTCNT_TXEE)
78 * 68328 and 68EZ328 UARTS are a little bit different. EZ328 has special
79 * "Old data interrupt" which occures whenever the data stay in the FIFO
80 * longer than 30 bits time. This allows us to use FIFO without compromising
81 * latency. '328 does not have this feature and without the real 328-based
82 * board I would assume that RXRE is the safest setting.
84 * For EZ328 I use RXHE (Half empty) interrupt to reduce the number of
85 * interrupts. RXFE (receive queue full) causes the system to lose data
86 * at least at 115200 baud
88 * If your board is busy doing other stuff, you might consider to use
89 * RXRE (data ready intrrupt) instead.
91 * The other option is to make these INTR masks run-time configurable, so
92 * that people can dynamically adapt them according to the current usage.
93 * -- Vladimir Gurevich
97 #if defined(CONFIG_M68EZ328) || defined(CONFIG_M68VZ328)
98 #define USTCNT_RX_INTR_MASK (USTCNT_RXHE | USTCNT_ODEN)
99 #elif defined(CONFIG_M68328)
100 #define USTCNT_RX_INTR_MASK (USTCNT_RXRE)
102 #error Please, define the Rx interrupt events for your CPU
107 * This is our internal structure for each serial port's state.
110 struct tty_port tport;
111 char is_cons; /* Is this our console. */
116 int type; /* UART type */
118 int x_char; /* xon/xoff character */
120 unsigned char *xmit_buf;
126 #define SERIAL_MAGIC 0x5301
129 * Define the number of ports supported and their irqs.
133 static struct m68k_serial m68k_soft[NR_PORTS];
135 static unsigned int uart_irqs[NR_PORTS] = { UART_IRQ_NUM };
137 /* multiple ports are contiguous in memory */
138 m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
140 struct tty_driver *serial_driver;
142 static void change_speed(struct m68k_serial *info, struct tty_struct *tty);
145 * Setup for console. Argument comes from the boot command line.
148 /* note: this is messy, but it works, again, perhaps defined somewhere else?*/
149 #ifdef CONFIG_M68VZ328
150 #define CONSOLE_BAUD_RATE 19200
151 #define DEFAULT_CBAUD B19200
155 #ifndef CONSOLE_BAUD_RATE
156 #define CONSOLE_BAUD_RATE 9600
157 #define DEFAULT_CBAUD B9600
161 static int m68328_console_initted = 0;
162 static int m68328_console_baud = CONSOLE_BAUD_RATE;
163 static int m68328_console_cbaud = DEFAULT_CBAUD;
166 static inline int serial_paranoia_check(struct m68k_serial *info,
167 char *name, const char *routine)
169 #ifdef SERIAL_PARANOIA_CHECK
170 static const char *badmagic =
171 "Warning: bad magic number for serial struct %s in %s\n";
172 static const char *badinfo =
173 "Warning: null m68k_serial for %s in %s\n";
176 printk(badinfo, name, routine);
179 if (info->magic != SERIAL_MAGIC) {
180 printk(badmagic, name, routine);
188 * This is used to figure out the divisor speeds and the timeouts
190 static int baud_table[] = {
191 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
192 9600, 19200, 38400, 57600, 115200, 0 };
194 /* Utility routines */
195 static inline int get_baud(struct m68k_serial *ss)
197 unsigned long result = 115200;
198 unsigned short int baud = uart_addr[ss->line].ubaud;
199 if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400;
200 result >>= GET_FIELD(baud, UBAUD_DIVIDE);
206 * ------------------------------------------------------------
207 * rs_stop() and rs_start()
209 * This routines are called before setting or resetting tty->stopped.
210 * They enable or disable transmitter interrupts, as necessary.
211 * ------------------------------------------------------------
213 static void rs_stop(struct tty_struct *tty)
215 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
216 m68328_uart *uart = &uart_addr[info->line];
219 if (serial_paranoia_check(info, tty->name, "rs_stop"))
222 local_irq_save(flags);
223 uart->ustcnt &= ~USTCNT_TXEN;
224 local_irq_restore(flags);
227 static int rs_put_char(char ch)
232 local_irq_save(flags);
234 while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
241 local_irq_restore(flags);
245 static void rs_start(struct tty_struct *tty)
247 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
248 m68328_uart *uart = &uart_addr[info->line];
251 if (serial_paranoia_check(info, tty->name, "rs_start"))
254 local_irq_save(flags);
255 if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
257 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
259 uart->ustcnt |= USTCNT_TXEN;
262 local_irq_restore(flags);
265 static void receive_chars(struct m68k_serial *info, unsigned short rx)
267 m68328_uart *uart = &uart_addr[info->line];
268 unsigned char ch, flag;
271 * This do { } while() loop will get ALL chars out of Rx FIFO
273 #ifndef CONFIG_XCOPILOT_BUGS
276 ch = GET_FIELD(rx, URX_RXDATA);
279 if(URX_BREAK & rx) { /* whee, break received */
281 #ifdef CONFIG_MAGIC_SYSRQ
282 } else if (ch == 0x10) { /* ^P */
286 /* show_net_buffers(); */
288 } else if (ch == 0x12) { /* ^R */
291 #endif /* CONFIG_MAGIC_SYSRQ */
297 if (rx & URX_PARITY_ERROR)
299 else if (rx & URX_OVRUN)
301 else if (rx & URX_FRAME_ERROR)
304 tty_insert_flip_char(&info->tport, ch, flag);
305 #ifndef CONFIG_XCOPILOT_BUGS
306 } while((rx = uart->urx.w) & URX_DATA_READY);
309 tty_schedule_flip(&info->tport);
312 static void transmit_chars(struct m68k_serial *info, struct tty_struct *tty)
314 m68328_uart *uart = &uart_addr[info->line];
318 uart->utx.b.txdata = info->x_char;
320 goto clear_and_return;
323 if ((info->xmit_cnt <= 0) || !tty || tty->stopped) {
324 /* That's peculiar... TX ints off */
325 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
326 goto clear_and_return;
330 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
331 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
334 if(info->xmit_cnt <= 0) {
335 /* All done for now... TX ints off */
336 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
337 goto clear_and_return;
341 /* Clear interrupt (should be auto)*/
346 * This is the serial driver's generic interrupt routine
348 irqreturn_t rs_interrupt(int irq, void *dev_id)
350 struct m68k_serial *info = dev_id;
351 struct tty_struct *tty = tty_port_tty_get(&info->tport);
356 uart = &uart_addr[info->line];
362 if (rx & URX_DATA_READY)
363 receive_chars(info, rx);
364 if (tx & UTX_TX_AVAIL)
365 transmit_chars(info, tty);
367 receive_chars(info, rx);
374 static int startup(struct m68k_serial *info, struct tty_struct *tty)
376 m68328_uart *uart = &uart_addr[info->line];
379 if (info->tport.flags & ASYNC_INITIALIZED)
382 if (!info->xmit_buf) {
383 info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL);
388 local_irq_save(flags);
391 * Clear the FIFO buffers and disable them
392 * (they will be reenabled in change_speed())
395 uart->ustcnt = USTCNT_UEN;
396 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN;
400 * Finally, enable sequencing and interrupts
403 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN |
404 USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK;
406 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK;
410 clear_bit(TTY_IO_ERROR, &tty->flags);
411 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
414 * and set the speed of the serial port
417 change_speed(info, tty);
419 info->tport.flags |= ASYNC_INITIALIZED;
420 local_irq_restore(flags);
425 * This routine will shutdown a serial port; interrupts are disabled, and
426 * DTR is dropped if the hangup on close termio flag is on.
428 static void shutdown(struct m68k_serial *info, struct tty_struct *tty)
430 m68328_uart *uart = &uart_addr[info->line];
433 uart->ustcnt = 0; /* All off! */
434 if (!(info->tport.flags & ASYNC_INITIALIZED))
437 local_irq_save(flags);
439 if (info->xmit_buf) {
440 free_page((unsigned long) info->xmit_buf);
445 set_bit(TTY_IO_ERROR, &tty->flags);
447 info->tport.flags &= ~ASYNC_INITIALIZED;
448 local_irq_restore(flags);
452 int divisor, prescale;
454 #ifndef CONFIG_M68VZ328
455 hw_baud_table[18] = {
470 {1,0x26}, /* 19200 */
471 {0,0x26}, /* 38400 */
472 {1,0x38}, /* 57600 */
473 {0,0x38}, /* 115200 */
476 hw_baud_table[18] = {
491 {2,0x26}, /* 19200 */
492 {1,0x26}, /* 38400 */
493 {0,0x26}, /* 57600 */
494 {1,0x38}, /* 115200 */
497 /* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
500 * This routine is called to set the UART divisor registers to match
501 * the specified baud rate for a serial port.
503 static void change_speed(struct m68k_serial *info, struct tty_struct *tty)
505 m68328_uart *uart = &uart_addr[info->line];
507 unsigned short ustcnt;
511 cflag = tty->termios.c_cflag;
512 if (!(port = info->port))
515 ustcnt = uart->ustcnt;
516 uart->ustcnt = ustcnt & ~USTCNT_TXEN;
520 i = (i & ~CBAUDEX) + B38400;
523 uart->ubaud = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
524 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
526 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
528 if ((cflag & CSIZE) == CS8)
529 ustcnt |= USTCNT_8_7;
532 ustcnt |= USTCNT_STOP;
535 ustcnt |= USTCNT_PARITYEN;
537 ustcnt |= USTCNT_ODD_EVEN;
539 #ifdef CONFIG_SERIAL_68328_RTS_CTS
540 if (cflag & CRTSCTS) {
541 uart->utx.w &= ~ UTX_NOCTS;
543 uart->utx.w |= UTX_NOCTS;
547 ustcnt |= USTCNT_TXEN;
549 uart->ustcnt = ustcnt;
554 * Fair output driver allows a process to speak.
556 static void rs_fair_output(void)
558 int left; /* Output no more than that */
560 struct m68k_serial *info = &m68k_soft[0];
563 if (info == 0) return;
564 if (info->xmit_buf == 0) return;
566 local_irq_save(flags);
567 left = info->xmit_cnt;
569 c = info->xmit_buf[info->xmit_tail];
570 info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
572 local_irq_restore(flags);
576 local_irq_save(flags);
577 left = min(info->xmit_cnt, left-1);
580 /* Last character is being transmitted now (hopefully). */
583 local_irq_restore(flags);
588 * m68k_console_print is registered for printk.
590 void console_print_68328(const char *p)
594 while((c=*(p++)) != 0) {
600 /* Comment this if you want to have a strict interrupt-driven output */
606 static void rs_set_ldisc(struct tty_struct *tty)
608 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
610 if (serial_paranoia_check(info, tty->name, "rs_set_ldisc"))
613 info->is_cons = (tty->termios.c_line == N_TTY);
615 printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
618 static void rs_flush_chars(struct tty_struct *tty)
620 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
621 m68328_uart *uart = &uart_addr[info->line];
624 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
630 /* Enable transmitter */
631 local_irq_save(flags);
633 if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf) {
634 local_irq_restore(flags);
639 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
641 uart->ustcnt |= USTCNT_TXEN;
645 if (uart->utx.w & UTX_TX_AVAIL) {
650 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
651 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
656 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
659 local_irq_restore(flags);
662 extern void console_printn(const char * b, int count);
664 static int rs_write(struct tty_struct * tty,
665 const unsigned char *buf, int count)
668 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
669 m68328_uart *uart = &uart_addr[info->line];
672 if (serial_paranoia_check(info, tty->name, "rs_write"))
675 if (!tty || !info->xmit_buf)
678 local_save_flags(flags);
681 c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
682 SERIAL_XMIT_SIZE - info->xmit_head));
683 local_irq_restore(flags);
688 memcpy(info->xmit_buf + info->xmit_head, buf, c);
691 info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
693 local_irq_restore(flags);
699 if (info->xmit_cnt && !tty->stopped) {
700 /* Enable transmitter */
703 while(info->xmit_cnt) {
706 uart->ustcnt |= USTCNT_TXEN;
708 uart->ustcnt |= USTCNT_TX_INTR_MASK;
710 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
712 if (uart->utx.w & UTX_TX_AVAIL) {
713 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
714 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
721 local_irq_restore(flags);
727 static int rs_write_room(struct tty_struct *tty)
729 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
732 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
734 ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
740 static int rs_chars_in_buffer(struct tty_struct *tty)
742 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
744 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
746 return info->xmit_cnt;
749 static void rs_flush_buffer(struct tty_struct *tty)
751 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
754 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
756 local_irq_save(flags);
757 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
758 local_irq_restore(flags);
763 * ------------------------------------------------------------
766 * This routine is called by the upper-layer tty layer to signal that
767 * incoming characters should be throttled.
768 * ------------------------------------------------------------
770 static void rs_throttle(struct tty_struct * tty)
772 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
774 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
778 info->x_char = STOP_CHAR(tty);
780 /* Turn off RTS line (do this atomic) */
783 static void rs_unthrottle(struct tty_struct * tty)
785 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
787 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
794 info->x_char = START_CHAR(tty);
797 /* Assert RTS line (do this atomic) */
801 * ------------------------------------------------------------
802 * rs_ioctl() and friends
803 * ------------------------------------------------------------
806 static int get_serial_info(struct m68k_serial * info,
807 struct serial_struct * retinfo)
809 struct serial_struct tmp;
813 memset(&tmp, 0, sizeof(tmp));
814 tmp.type = info->type;
815 tmp.line = info->line;
816 tmp.port = info->port;
818 tmp.flags = info->tport.flags;
819 tmp.baud_base = info->baud_base;
820 tmp.close_delay = info->tport.close_delay;
821 tmp.closing_wait = info->tport.closing_wait;
822 tmp.custom_divisor = info->custom_divisor;
823 if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
829 static int set_serial_info(struct m68k_serial *info, struct tty_struct *tty,
830 struct serial_struct * new_info)
832 struct tty_port *port = &info->tport;
833 struct serial_struct new_serial;
834 struct m68k_serial old_info;
839 if (copy_from_user(&new_serial, new_info, sizeof(new_serial)))
843 if (!capable(CAP_SYS_ADMIN)) {
844 if ((new_serial.baud_base != info->baud_base) ||
845 (new_serial.type != info->type) ||
846 (new_serial.close_delay != port->close_delay) ||
847 ((new_serial.flags & ~ASYNC_USR_MASK) !=
848 (port->flags & ~ASYNC_USR_MASK)))
850 port->flags = ((port->flags & ~ASYNC_USR_MASK) |
851 (new_serial.flags & ASYNC_USR_MASK));
852 info->custom_divisor = new_serial.custom_divisor;
860 * OK, past this point, all the error checking has been done.
861 * At this point, we start making changes.....
864 info->baud_base = new_serial.baud_base;
865 port->flags = ((port->flags & ~ASYNC_FLAGS) |
866 (new_serial.flags & ASYNC_FLAGS));
867 info->type = new_serial.type;
868 port->close_delay = new_serial.close_delay;
869 port->closing_wait = new_serial.closing_wait;
872 retval = startup(info, tty);
877 * get_lsr_info - get line status register info
879 * Purpose: Let user call ioctl() to get info when the UART physically
880 * is emptied. On bus types like RS485, the transmitter must
881 * release the bus after transmitting. This must be done when
882 * the transmit shift register is empty, not be done when the
883 * transmit holding register is empty. This functionality
884 * allows an RS485 driver to be written in user space.
886 static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
888 #ifdef CONFIG_SERIAL_68328_RTS_CTS
889 m68328_uart *uart = &uart_addr[info->line];
891 unsigned char status;
894 local_irq_save(flags);
895 #ifdef CONFIG_SERIAL_68328_RTS_CTS
896 status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
900 local_irq_restore(flags);
901 return put_user(status, value);
905 * This routine sends a break character out the serial port.
907 static void send_break(struct m68k_serial * info, unsigned int duration)
909 m68328_uart *uart = &uart_addr[info->line];
913 local_irq_save(flags);
915 uart->utx.w |= UTX_SEND_BREAK;
916 msleep_interruptible(duration);
917 uart->utx.w &= ~UTX_SEND_BREAK;
919 local_irq_restore(flags);
922 static int rs_ioctl(struct tty_struct *tty,
923 unsigned int cmd, unsigned long arg)
925 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
928 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
931 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
932 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
933 (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
934 if (tty->flags & (1 << TTY_IO_ERROR))
939 case TCSBRK: /* SVID version: non-zero arg --> no break */
940 retval = tty_check_change(tty);
943 tty_wait_until_sent(tty, 0);
945 send_break(info, 250); /* 1/4 second */
947 case TCSBRKP: /* support for POSIX tcsendbreak() */
948 retval = tty_check_change(tty);
951 tty_wait_until_sent(tty, 0);
952 send_break(info, arg ? arg*(100) : 250);
955 return get_serial_info(info,
956 (struct serial_struct *) arg);
958 return set_serial_info(info, tty,
959 (struct serial_struct *) arg);
960 case TIOCSERGETLSR: /* Get line status register */
961 return get_lsr_info(info, (unsigned int *) arg);
963 if (copy_to_user((struct m68k_serial *) arg,
964 info, sizeof(struct m68k_serial)))
973 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
975 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
977 change_speed(info, tty);
979 if ((old_termios->c_cflag & CRTSCTS) &&
980 !(tty->termios.c_cflag & CRTSCTS))
986 * ------------------------------------------------------------
989 * This routine is called when the serial port gets closed. First, we
990 * wait for the last remaining data to be sent. Then, we unlink its
991 * S structure from the interrupt chain if necessary, and we free
992 * that IRQ if nothing is left in the chain.
993 * ------------------------------------------------------------
995 static void rs_close(struct tty_struct *tty, struct file * filp)
997 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
998 struct tty_port *port = &info->tport;
999 m68328_uart *uart = &uart_addr[info->line];
1000 unsigned long flags;
1002 if (serial_paranoia_check(info, tty->name, "rs_close"))
1005 local_irq_save(flags);
1007 if (tty_hung_up_p(filp)) {
1008 local_irq_restore(flags);
1012 if ((tty->count == 1) && (port->count != 1)) {
1014 * Uh, oh. tty->count is 1, which means that the tty
1015 * structure will be freed. Info->count should always
1016 * be one in these conditions. If it's greater than
1017 * one, we've got real problems, since it means the
1018 * serial port won't be shutdown.
1020 printk("rs_close: bad serial port count; tty->count is 1, "
1021 "port->count is %d\n", port->count);
1024 if (--port->count < 0) {
1025 printk("rs_close: bad serial port count for ttyS%d: %d\n",
1026 info->line, port->count);
1030 local_irq_restore(flags);
1033 port->flags |= ASYNC_CLOSING;
1035 * Now we wait for the transmit buffer to clear; and we notify
1036 * the line discipline to only process XON/XOFF characters.
1039 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1040 tty_wait_until_sent(tty, port->closing_wait);
1042 * At this point we stop accepting input. To do this, we
1043 * disable the receive line status interrupts, and tell the
1044 * interrupt driver to stop checking the data ready bit in the
1045 * line status register.
1048 uart->ustcnt &= ~USTCNT_RXEN;
1049 uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
1051 shutdown(info, tty);
1052 rs_flush_buffer(tty);
1054 tty_ldisc_flush(tty);
1056 tty_port_tty_set(&info->tport, NULL);
1057 #warning "This is not and has never been valid so fix it"
1059 if (tty->ldisc.num != ldiscs[N_TTY].num) {
1060 if (tty->ldisc.close)
1061 (tty->ldisc.close)(tty);
1062 tty->ldisc = ldiscs[N_TTY];
1063 tty->termios.c_line = N_TTY;
1064 if (tty->ldisc.open)
1065 (tty->ldisc.open)(tty);
1068 if (port->blocked_open) {
1069 if (port->close_delay)
1070 msleep_interruptible(jiffies_to_msecs(port->close_delay));
1071 wake_up_interruptible(&port->open_wait);
1073 port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
1074 wake_up_interruptible(&port->close_wait);
1075 local_irq_restore(flags);
1079 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1081 void rs_hangup(struct tty_struct *tty)
1083 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1085 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1088 rs_flush_buffer(tty);
1089 shutdown(info, tty);
1090 info->tport.count = 0;
1091 info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
1092 tty_port_tty_set(&info->tport, NULL);
1093 wake_up_interruptible(&info->tport.open_wait);
1097 * This routine is called whenever a serial port is opened. It
1098 * enables interrupts for a serial port, linking in its S structure into
1099 * the IRQ chain. It also performs the serial-specific
1100 * initialization for the tty structure.
1102 int rs_open(struct tty_struct *tty, struct file * filp)
1104 struct m68k_serial *info;
1107 info = &m68k_soft[tty->index];
1109 if (serial_paranoia_check(info, tty->name, "rs_open"))
1112 info->tport.count++;
1113 tty->driver_data = info;
1114 tty_port_tty_set(&info->tport, tty);
1117 * Start up serial port
1119 retval = startup(info, tty);
1123 return tty_port_block_til_ready(&info->tport, tty, filp);
1126 /* Finally, routines used to initialize the serial driver. */
1128 static void show_serial_version(void)
1130 printk("MC68328 serial driver version 1.00\n");
1133 static const struct tty_operations rs_ops = {
1137 .flush_chars = rs_flush_chars,
1138 .write_room = rs_write_room,
1139 .chars_in_buffer = rs_chars_in_buffer,
1140 .flush_buffer = rs_flush_buffer,
1142 .throttle = rs_throttle,
1143 .unthrottle = rs_unthrottle,
1144 .set_termios = rs_set_termios,
1147 .hangup = rs_hangup,
1148 .set_ldisc = rs_set_ldisc,
1151 static const struct tty_port_operations rs_port_ops = {
1154 /* rs_init inits the driver */
1158 unsigned long flags;
1160 struct m68k_serial *info;
1162 serial_driver = alloc_tty_driver(NR_PORTS);
1166 show_serial_version();
1168 /* Initialize the tty_driver structure */
1169 /* SPARC: Not all of this is exactly right for us. */
1171 serial_driver->name = "ttyS";
1172 serial_driver->major = TTY_MAJOR;
1173 serial_driver->minor_start = 64;
1174 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1175 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1176 serial_driver->init_termios = tty_std_termios;
1177 serial_driver->init_termios.c_cflag =
1178 m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL;
1179 serial_driver->flags = TTY_DRIVER_REAL_RAW;
1180 tty_set_operations(serial_driver, &rs_ops);
1182 local_irq_save(flags);
1184 for(i=0;i<NR_PORTS;i++) {
1186 info = &m68k_soft[i];
1187 tty_port_init(&info->tport);
1188 info->tport.ops = &rs_port_ops;
1189 info->magic = SERIAL_MAGIC;
1190 info->port = (int) &uart_addr[i];
1191 info->irq = uart_irqs[i];
1192 info->custom_divisor = 16;
1195 info->is_cons = 1; /* Means shortcuts work */
1197 printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line,
1198 info->port, info->irq);
1199 printk(" is a builtin MC68328 UART\n");
1201 #ifdef CONFIG_M68VZ328
1203 PJSEL &= 0xCF; /* PSW enable second port output */
1206 if (request_irq(uart_irqs[i],
1209 "M68328_UART", info))
1210 panic("Unable to attach 68328 serial interrupt\n");
1212 tty_port_link_device(&info->tport, serial_driver, i);
1214 local_irq_restore(flags);
1216 if (tty_register_driver(serial_driver)) {
1217 put_tty_driver(serial_driver);
1218 for (i = 0; i < NR_PORTS; i++)
1219 tty_port_destroy(&m68k_soft[i].tport);
1220 printk(KERN_ERR "Couldn't register serial driver\n");
1227 module_init(rs68328_init);
1231 static void m68328_set_baud(void)
1233 unsigned short ustcnt;
1237 USTCNT = ustcnt & ~USTCNT_TXEN;
1240 for (i = 0; i < ARRAY_SIZE(baud_table); i++)
1241 if (baud_table[i] == m68328_console_baud)
1243 if (i >= ARRAY_SIZE(baud_table)) {
1244 m68328_console_baud = 9600;
1248 UBAUD = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
1249 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
1250 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
1251 ustcnt |= USTCNT_8_7;
1252 ustcnt |= USTCNT_TXEN;
1254 m68328_console_initted = 1;
1259 int m68328_console_setup(struct console *cp, char *arg)
1261 int i, n = CONSOLE_BAUD_RATE;
1267 n = simple_strtoul(arg,NULL,0);
1269 for (i = 0; i < ARRAY_SIZE(baud_table); i++)
1270 if (baud_table[i] == n)
1272 if (i < ARRAY_SIZE(baud_table)) {
1273 m68328_console_baud = n;
1274 m68328_console_cbaud = 0;
1276 m68328_console_cbaud |= CBAUDEX;
1279 m68328_console_cbaud |= i;
1282 m68328_set_baud(); /* make sure baud rate changes */
1287 static struct tty_driver *m68328_console_device(struct console *c, int *index)
1290 return serial_driver;
1294 void m68328_console_write (struct console *co, const char *str,
1297 if (!m68328_console_initted)
1302 rs_put_char( *str++ );
1307 static struct console m68328_driver = {
1309 .write = m68328_console_write,
1310 .device = m68328_console_device,
1311 .setup = m68328_console_setup,
1312 .flags = CON_PRINTBUFFER,
1317 static int __init m68328_console_init(void)
1319 register_console(&m68328_driver);
1323 console_initcall(m68328_console_init);