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/signal.h>
21 #include <linux/sched.h>
22 #include <linux/timer.h>
23 #include <linux/interrupt.h>
24 #include <linux/tty.h>
25 #include <linux/tty_flip.h>
26 #include <linux/config.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>
42 #include <asm/system.h>
43 #include <asm/segment.h>
44 #include <asm/delay.h>
45 #include <asm/uaccess.h>
48 /* note: perhaps we can murge these files, so that you can just
49 * define 1 of them, and they can sort that out for themselves
51 #if defined(CONFIG_M68EZ328)
52 #include <asm/MC68EZ328.h>
54 #if defined(CONFIG_M68VZ328)
55 #include <asm/MC68VZ328.h>
57 #include <asm/MC68328.h>
58 #endif /* CONFIG_M68VZ328 */
59 #endif /* CONFIG_M68EZ328 */
61 #include "68328serial.h"
63 /* Turn off usage of real serial interrupt code, to "support" Copilot */
64 #ifdef CONFIG_XCOPILOT_BUGS
70 static struct m68k_serial m68k_soft[NR_PORTS];
71 struct m68k_serial *IRQ_ports[NR_IRQS];
73 static unsigned int uart_irqs[NR_PORTS] = UART_IRQ_DEFNS;
75 /* multiple ports are contiguous in memory */
76 m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
78 struct tty_struct m68k_ttys;
79 struct m68k_serial *m68k_consinfo = 0;
81 #define M68K_CLOCK (16667000) /* FIXME: 16MHz is likely wrong */
84 extern wait_queue_head_t keypress_wait;
87 struct tty_driver *serial_driver;
89 /* serial subtype definitions */
90 #define SERIAL_TYPE_NORMAL 1
92 /* number of characters left in xmit buffer before we ask for more */
93 #define WAKEUP_CHARS 256
95 /* Debugging... DEBUG_INTR is bad to use when one of the zs
96 * lines is your console ;(
98 #undef SERIAL_DEBUG_INTR
99 #undef SERIAL_DEBUG_OPEN
100 #undef SERIAL_DEBUG_FLOW
102 #define RS_ISR_PASS_LIMIT 256
104 #define _INLINE_ inline
106 static void change_speed(struct m68k_serial *info);
109 * Setup for console. Argument comes from the boot command line.
112 #if defined(CONFIG_M68EZ328ADS) || defined(CONFIG_ALMA_ANS) || defined(CONFIG_DRAGONIXVZ)
113 #define CONSOLE_BAUD_RATE 115200
114 #define DEFAULT_CBAUD B115200
117 /* note: this is messy, but it works, again, perhaps defined somewhere else?*/
118 #ifdef CONFIG_M68VZ328
119 #define CONSOLE_BAUD_RATE 19200
120 #define DEFAULT_CBAUD B19200
125 #ifndef CONSOLE_BAUD_RATE
126 #define CONSOLE_BAUD_RATE 9600
127 #define DEFAULT_CBAUD B9600
131 static int m68328_console_initted = 0;
132 static int m68328_console_baud = CONSOLE_BAUD_RATE;
133 static int m68328_console_cbaud = DEFAULT_CBAUD;
137 * tmp_buf is used as a temporary buffer by serial_write. We need to
138 * lock it in case the memcpy_fromfs blocks while swapping in a page,
139 * and some other program tries to do a serial write at the same time.
140 * Since the lock will only come under contention when the system is
141 * swapping and available memory is low, it makes sense to share one
142 * buffer across all the serial ports, since it significantly saves
143 * memory if large numbers of serial ports are open.
145 static unsigned char tmp_buf[SERIAL_XMIT_SIZE]; /* This is cheating */
146 DECLARE_MUTEX(tmp_buf_sem);
148 static inline int serial_paranoia_check(struct m68k_serial *info,
149 char *name, const char *routine)
151 #ifdef SERIAL_PARANOIA_CHECK
152 static const char *badmagic =
153 "Warning: bad magic number for serial struct %s in %s\n";
154 static const char *badinfo =
155 "Warning: null m68k_serial for %s in %s\n";
158 printk(badinfo, name, routine);
161 if (info->magic != SERIAL_MAGIC) {
162 printk(badmagic, name, routine);
170 * This is used to figure out the divisor speeds and the timeouts
172 static int baud_table[] = {
173 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
174 9600, 19200, 38400, 57600, 115200, 0 };
176 #define BAUD_TABLE_SIZE (sizeof(baud_table)/sizeof(baud_table[0]))
178 /* Sets or clears DTR/RTS on the requested line */
179 static inline void m68k_rtsdtr(struct m68k_serial *ss, int set)
182 /* set the RTS/CTS line */
189 /* Utility routines */
190 static inline int get_baud(struct m68k_serial *ss)
192 unsigned long result = 115200;
193 unsigned short int baud = uart_addr[ss->line].ubaud;
194 if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400;
195 result >>= GET_FIELD(baud, UBAUD_DIVIDE);
201 * ------------------------------------------------------------
202 * rs_stop() and rs_start()
204 * This routines are called before setting or resetting tty->stopped.
205 * They enable or disable transmitter interrupts, as necessary.
206 * ------------------------------------------------------------
208 static void rs_stop(struct tty_struct *tty)
210 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
211 m68328_uart *uart = &uart_addr[info->line];
214 if (serial_paranoia_check(info, tty->name, "rs_stop"))
217 save_flags(flags); cli();
218 uart->ustcnt &= ~USTCNT_TXEN;
219 restore_flags(flags);
222 static void rs_put_char(char ch)
224 int flags, loops = 0;
226 save_flags(flags); cli();
228 while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
235 restore_flags(flags);
238 static void rs_start(struct tty_struct *tty)
240 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
241 m68328_uart *uart = &uart_addr[info->line];
244 if (serial_paranoia_check(info, tty->name, "rs_start"))
247 save_flags(flags); cli();
248 if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
250 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
252 uart->ustcnt |= USTCNT_TXEN;
255 restore_flags(flags);
258 /* Drop into either the boot monitor or kadb upon receiving a break
259 * from keyboard/console input.
261 static void batten_down_hatches(void)
263 /* Drop into the debugger */
266 static _INLINE_ void status_handle(struct m68k_serial *info, unsigned short status)
270 if((info->tty->termios->c_cflag & CRTSCTS) &&
271 ((info->curregs[3] & AUTO_ENAB)==0)) {
272 info->curregs[3] |= AUTO_ENAB;
273 info->pendregs[3] |= AUTO_ENAB;
274 write_zsreg(info->m68k_channel, 3, info->curregs[3]);
277 if((info->curregs[3] & AUTO_ENAB)) {
278 info->curregs[3] &= ~AUTO_ENAB;
279 info->pendregs[3] &= ~AUTO_ENAB;
280 write_zsreg(info->m68k_channel, 3, info->curregs[3]);
284 /* If this is console input and this is a
285 * 'break asserted' status change interrupt
286 * see if we can drop into the debugger
288 if((status & URX_BREAK) && info->break_abort)
289 batten_down_hatches();
293 static _INLINE_ void receive_chars(struct m68k_serial *info, struct pt_regs *regs, unsigned short rx)
295 struct tty_struct *tty = info->tty;
296 m68328_uart *uart = &uart_addr[info->line];
300 * This do { } while() loop will get ALL chars out of Rx FIFO
302 #ifndef CONFIG_XCOPILOT_BUGS
305 ch = GET_FIELD(rx, URX_RXDATA);
308 if(URX_BREAK & rx) { /* whee, break received */
309 status_handle(info, rx);
311 #ifdef CONFIG_MAGIC_SYSRQ
312 } else if (ch == 0x10) { /* ^P */
316 /* show_net_buffers(); */
318 } else if (ch == 0x12) { /* ^R */
319 machine_restart(NULL);
321 #endif /* CONFIG_MAGIC_SYSRQ */
323 /* It is a 'keyboard interrupt' ;-) */
324 #ifdef CONFIG_CONSOLE
325 wake_up(&keypress_wait);
333 * Make sure that we do not overflow the buffer
335 if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
336 schedule_work(&tty->flip.work);
340 if(rx & URX_PARITY_ERROR) {
341 *tty->flip.flag_buf_ptr++ = TTY_PARITY;
342 status_handle(info, rx);
343 } else if(rx & URX_OVRUN) {
344 *tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
345 status_handle(info, rx);
346 } else if(rx & URX_FRAME_ERROR) {
347 *tty->flip.flag_buf_ptr++ = TTY_FRAME;
348 status_handle(info, rx);
350 *tty->flip.flag_buf_ptr++ = 0; /* XXX */
352 *tty->flip.char_buf_ptr++ = ch;
355 #ifndef CONFIG_XCOPILOT_BUGS
356 } while((rx = uart->urx.w) & URX_DATA_READY);
359 schedule_work(&tty->flip.work);
365 static _INLINE_ void transmit_chars(struct m68k_serial *info)
367 m68328_uart *uart = &uart_addr[info->line];
371 uart->utx.b.txdata = info->x_char;
373 goto clear_and_return;
376 if((info->xmit_cnt <= 0) || info->tty->stopped) {
377 /* That's peculiar... TX ints off */
378 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
379 goto clear_and_return;
383 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
384 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
387 if (info->xmit_cnt < WAKEUP_CHARS)
388 schedule_work(&info->tqueue);
390 if(info->xmit_cnt <= 0) {
391 /* All done for now... TX ints off */
392 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
393 goto clear_and_return;
397 /* Clear interrupt (should be auto)*/
402 * This is the serial driver's generic interrupt routine
404 irqreturn_t rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
406 struct m68k_serial * info;
411 info = IRQ_ports[irq];
415 uart = &uart_addr[info->line];
421 if (rx & URX_DATA_READY) receive_chars(info, regs, rx);
422 if (tx & UTX_TX_AVAIL) transmit_chars(info);
424 receive_chars(info, regs, rx);
429 static void do_softint(void *private)
431 struct m68k_serial *info = (struct m68k_serial *) private;
432 struct tty_struct *tty;
438 if (clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
445 * This routine is called from the scheduler tqueue when the interrupt
446 * routine has signalled that a hangup has occurred. The path of
447 * hangup processing is:
449 * serial interrupt routine -> (scheduler tqueue) ->
450 * do_serial_hangup() -> tty->hangup() -> rs_hangup()
453 static void do_serial_hangup(void *private)
455 struct m68k_serial *info = (struct m68k_serial *) private;
456 struct tty_struct *tty;
466 static int startup(struct m68k_serial * info)
468 m68328_uart *uart = &uart_addr[info->line];
471 if (info->flags & S_INITIALIZED)
474 if (!info->xmit_buf) {
475 info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL);
480 save_flags(flags); cli();
483 * Clear the FIFO buffers and disable them
484 * (they will be reenabled in change_speed())
487 uart->ustcnt = USTCNT_UEN;
488 info->xmit_fifo_size = 1;
489 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN;
493 * Finally, enable sequencing and interrupts
496 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN |
497 USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK;
499 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK;
503 clear_bit(TTY_IO_ERROR, &info->tty->flags);
504 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
507 * and set the speed of the serial port
512 info->flags |= S_INITIALIZED;
513 restore_flags(flags);
518 * This routine will shutdown a serial port; interrupts are disabled, and
519 * DTR is dropped if the hangup on close termio flag is on.
521 static void shutdown(struct m68k_serial * info)
523 m68328_uart *uart = &uart_addr[info->line];
526 uart->ustcnt = 0; /* All off! */
527 if (!(info->flags & S_INITIALIZED))
530 save_flags(flags); cli(); /* Disable interrupts */
532 if (info->xmit_buf) {
533 free_page((unsigned long) info->xmit_buf);
538 set_bit(TTY_IO_ERROR, &info->tty->flags);
540 info->flags &= ~S_INITIALIZED;
541 restore_flags(flags);
545 int divisor, prescale;
547 #ifndef CONFIG_M68VZ328
548 hw_baud_table[18] = {
563 {1,0x26}, /* 19200 */
564 {0,0x26}, /* 38400 */
565 {1,0x38}, /* 57600 */
566 {0,0x38}, /* 115200 */
569 hw_baud_table[18] = {
584 {2,0x26}, /* 19200 */
585 {1,0x26}, /* 38400 */
586 {0,0x26}, /* 57600 */
587 {1,0x38}, /* 115200 */
590 /* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
593 * This routine is called to set the UART divisor registers to match
594 * the specified baud rate for a serial port.
596 static void change_speed(struct m68k_serial *info)
598 m68328_uart *uart = &uart_addr[info->line];
600 unsigned short ustcnt;
604 if (!info->tty || !info->tty->termios)
606 cflag = info->tty->termios->c_cflag;
607 if (!(port = info->port))
610 ustcnt = uart->ustcnt;
611 uart->ustcnt = ustcnt & ~USTCNT_TXEN;
615 i = (i & ~CBAUDEX) + B38400;
618 info->baud = baud_table[i];
619 uart->ubaud = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
620 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
622 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
624 if ((cflag & CSIZE) == CS8)
625 ustcnt |= USTCNT_8_7;
628 ustcnt |= USTCNT_STOP;
631 ustcnt |= USTCNT_PARITYEN;
633 ustcnt |= USTCNT_ODD_EVEN;
635 #ifdef CONFIG_SERIAL_68328_RTS_CTS
636 if (cflag & CRTSCTS) {
637 uart->utx.w &= ~ UTX_NOCTS;
639 uart->utx.w |= UTX_NOCTS;
643 ustcnt |= USTCNT_TXEN;
645 uart->ustcnt = ustcnt;
650 * Fair output driver allows a process to speak.
652 static void rs_fair_output(void)
654 int left; /* Output no more than that */
656 struct m68k_serial *info = &m68k_soft[0];
659 if (info == 0) return;
660 if (info->xmit_buf == 0) return;
662 save_flags(flags); cli();
663 left = info->xmit_cnt;
665 c = info->xmit_buf[info->xmit_tail];
666 info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
668 restore_flags(flags);
672 save_flags(flags); cli();
673 left = min(info->xmit_cnt, left-1);
676 /* Last character is being transmitted now (hopefully). */
679 restore_flags(flags);
684 * m68k_console_print is registered for printk.
686 void console_print_68328(const char *p)
690 while((c=*(p++)) != 0) {
696 /* Comment this if you want to have a strict interrupt-driven output */
702 static void rs_set_ldisc(struct tty_struct *tty)
704 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
706 if (serial_paranoia_check(info, tty->name, "rs_set_ldisc"))
709 info->is_cons = (tty->termios->c_line == N_TTY);
711 printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
714 static void rs_flush_chars(struct tty_struct *tty)
716 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
717 m68328_uart *uart = &uart_addr[info->line];
720 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
726 /* Enable transmitter */
727 save_flags(flags); cli();
729 if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
731 restore_flags(flags);
736 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
738 uart->ustcnt |= USTCNT_TXEN;
742 if (uart->utx.w & UTX_TX_AVAIL) {
747 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
748 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
753 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
756 restore_flags(flags);
759 extern void console_printn(const char * b, int count);
761 static int rs_write(struct tty_struct * tty,
762 const unsigned char *buf, int count)
765 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
766 m68328_uart *uart = &uart_addr[info->line];
769 if (serial_paranoia_check(info, tty->name, "rs_write"))
772 if (!tty || !info->xmit_buf)
778 c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
779 SERIAL_XMIT_SIZE - info->xmit_head));
783 memcpy(info->xmit_buf + info->xmit_head, buf, c);
784 info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
786 restore_flags(flags);
792 if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
793 /* Enable transmitter */
796 while(info->xmit_cnt) {
799 uart->ustcnt |= USTCNT_TXEN;
801 uart->ustcnt |= USTCNT_TX_INTR_MASK;
803 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
805 if (uart->utx.w & UTX_TX_AVAIL) {
806 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
807 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
814 restore_flags(flags);
816 restore_flags(flags);
820 static int rs_write_room(struct tty_struct *tty)
822 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
825 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
827 ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
833 static int rs_chars_in_buffer(struct tty_struct *tty)
835 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
837 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
839 return info->xmit_cnt;
842 static void rs_flush_buffer(struct tty_struct *tty)
844 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
846 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
849 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
855 * ------------------------------------------------------------
858 * This routine is called by the upper-layer tty layer to signal that
859 * incoming characters should be throttled.
860 * ------------------------------------------------------------
862 static void rs_throttle(struct tty_struct * tty)
864 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
866 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
870 info->x_char = STOP_CHAR(tty);
872 /* Turn off RTS line (do this atomic) */
875 static void rs_unthrottle(struct tty_struct * tty)
877 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
879 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
886 info->x_char = START_CHAR(tty);
889 /* Assert RTS line (do this atomic) */
893 * ------------------------------------------------------------
894 * rs_ioctl() and friends
895 * ------------------------------------------------------------
898 static int get_serial_info(struct m68k_serial * info,
899 struct serial_struct * retinfo)
901 struct serial_struct tmp;
905 memset(&tmp, 0, sizeof(tmp));
906 tmp.type = info->type;
907 tmp.line = info->line;
908 tmp.port = info->port;
910 tmp.flags = info->flags;
911 tmp.baud_base = info->baud_base;
912 tmp.close_delay = info->close_delay;
913 tmp.closing_wait = info->closing_wait;
914 tmp.custom_divisor = info->custom_divisor;
915 copy_to_user(retinfo,&tmp,sizeof(*retinfo));
919 static int set_serial_info(struct m68k_serial * info,
920 struct serial_struct * new_info)
922 struct serial_struct new_serial;
923 struct m68k_serial old_info;
928 copy_from_user(&new_serial,new_info,sizeof(new_serial));
931 if (!capable(CAP_SYS_ADMIN)) {
932 if ((new_serial.baud_base != info->baud_base) ||
933 (new_serial.type != info->type) ||
934 (new_serial.close_delay != info->close_delay) ||
935 ((new_serial.flags & ~S_USR_MASK) !=
936 (info->flags & ~S_USR_MASK)))
938 info->flags = ((info->flags & ~S_USR_MASK) |
939 (new_serial.flags & S_USR_MASK));
940 info->custom_divisor = new_serial.custom_divisor;
948 * OK, past this point, all the error checking has been done.
949 * At this point, we start making changes.....
952 info->baud_base = new_serial.baud_base;
953 info->flags = ((info->flags & ~S_FLAGS) |
954 (new_serial.flags & S_FLAGS));
955 info->type = new_serial.type;
956 info->close_delay = new_serial.close_delay;
957 info->closing_wait = new_serial.closing_wait;
960 retval = startup(info);
965 * get_lsr_info - get line status register info
967 * Purpose: Let user call ioctl() to get info when the UART physically
968 * is emptied. On bus types like RS485, the transmitter must
969 * release the bus after transmitting. This must be done when
970 * the transmit shift register is empty, not be done when the
971 * transmit holding register is empty. This functionality
972 * allows an RS485 driver to be written in user space.
974 static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
976 #ifdef CONFIG_SERIAL_68328_RTS_CTS
977 m68328_uart *uart = &uart_addr[info->line];
979 unsigned char status;
982 #ifdef CONFIG_SERIAL_68328_RTS_CTS
983 status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
988 put_user(status,value);
993 * This routine sends a break character out the serial port.
995 static void send_break( struct m68k_serial * info, int duration)
997 m68328_uart *uart = &uart_addr[info->line];
1001 set_current_state(TASK_INTERRUPTIBLE);
1005 uart->utx.w |= UTX_SEND_BREAK;
1006 schedule_timeout(duration);
1007 uart->utx.w &= ~UTX_SEND_BREAK;
1009 restore_flags(flags);
1012 static int rs_ioctl(struct tty_struct *tty, struct file * file,
1013 unsigned int cmd, unsigned long arg)
1016 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1019 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1022 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1023 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
1024 (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
1025 if (tty->flags & (1 << TTY_IO_ERROR))
1030 case TCSBRK: /* SVID version: non-zero arg --> no break */
1031 retval = tty_check_change(tty);
1034 tty_wait_until_sent(tty, 0);
1036 send_break(info, HZ/4); /* 1/4 second */
1038 case TCSBRKP: /* support for POSIX tcsendbreak() */
1039 retval = tty_check_change(tty);
1042 tty_wait_until_sent(tty, 0);
1043 send_break(info, arg ? arg*(HZ/10) : HZ/4);
1046 error = put_user(C_CLOCAL(tty) ? 1 : 0,
1047 (unsigned long *) arg);
1052 get_user(arg, (unsigned long *) arg);
1053 tty->termios->c_cflag =
1054 ((tty->termios->c_cflag & ~CLOCAL) |
1055 (arg ? CLOCAL : 0));
1058 error = verify_area(VERIFY_WRITE, (void *) arg,
1059 sizeof(struct serial_struct));
1062 return get_serial_info(info,
1063 (struct serial_struct *) arg);
1065 return set_serial_info(info,
1066 (struct serial_struct *) arg);
1067 case TIOCSERGETLSR: /* Get line status register */
1068 error = verify_area(VERIFY_WRITE, (void *) arg,
1069 sizeof(unsigned int));
1073 return get_lsr_info(info, (unsigned int *) arg);
1075 case TIOCSERGSTRUCT:
1076 error = verify_area(VERIFY_WRITE, (void *) arg,
1077 sizeof(struct m68k_serial));
1080 copy_to_user((struct m68k_serial *) arg,
1081 info, sizeof(struct m68k_serial));
1085 return -ENOIOCTLCMD;
1090 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
1092 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
1094 if (tty->termios->c_cflag == old_termios->c_cflag)
1099 if ((old_termios->c_cflag & CRTSCTS) &&
1100 !(tty->termios->c_cflag & CRTSCTS)) {
1101 tty->hw_stopped = 0;
1108 * ------------------------------------------------------------
1111 * This routine is called when the serial port gets closed. First, we
1112 * wait for the last remaining data to be sent. Then, we unlink its
1113 * S structure from the interrupt chain if necessary, and we free
1114 * that IRQ if nothing is left in the chain.
1115 * ------------------------------------------------------------
1117 static void rs_close(struct tty_struct *tty, struct file * filp)
1119 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1120 m68328_uart *uart = &uart_addr[info->line];
1121 unsigned long flags;
1123 if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1126 save_flags(flags); cli();
1128 if (tty_hung_up_p(filp)) {
1129 restore_flags(flags);
1133 if ((tty->count == 1) && (info->count != 1)) {
1135 * Uh, oh. tty->count is 1, which means that the tty
1136 * structure will be freed. Info->count should always
1137 * be one in these conditions. If it's greater than
1138 * one, we've got real problems, since it means the
1139 * serial port won't be shutdown.
1141 printk("rs_close: bad serial port count; tty->count is 1, "
1142 "info->count is %d\n", info->count);
1145 if (--info->count < 0) {
1146 printk("rs_close: bad serial port count for ttyS%d: %d\n",
1147 info->line, info->count);
1151 restore_flags(flags);
1154 info->flags |= S_CLOSING;
1156 * Now we wait for the transmit buffer to clear; and we notify
1157 * the line discipline to only process XON/XOFF characters.
1160 if (info->closing_wait != S_CLOSING_WAIT_NONE)
1161 tty_wait_until_sent(tty, info->closing_wait);
1163 * At this point we stop accepting input. To do this, we
1164 * disable the receive line status interrupts, and tell the
1165 * interrupt driver to stop checking the data ready bit in the
1166 * line status register.
1169 uart->ustcnt &= ~USTCNT_RXEN;
1170 uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
1173 if (tty->driver->flush_buffer)
1174 tty->driver->flush_buffer(tty);
1176 tty_ldisc_flush(tty);
1180 #warning "This is not and has never been valid so fix it"
1182 if (tty->ldisc.num != ldiscs[N_TTY].num) {
1183 if (tty->ldisc.close)
1184 (tty->ldisc.close)(tty);
1185 tty->ldisc = ldiscs[N_TTY];
1186 tty->termios->c_line = N_TTY;
1187 if (tty->ldisc.open)
1188 (tty->ldisc.open)(tty);
1191 if (info->blocked_open) {
1192 if (info->close_delay) {
1193 msleep_interruptible(jiffies_to_msecs(info->close_delay));
1195 wake_up_interruptible(&info->open_wait);
1197 info->flags &= ~(S_NORMAL_ACTIVE|S_CLOSING);
1198 wake_up_interruptible(&info->close_wait);
1199 restore_flags(flags);
1203 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1205 void rs_hangup(struct tty_struct *tty)
1207 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1209 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1212 rs_flush_buffer(tty);
1216 info->flags &= ~S_NORMAL_ACTIVE;
1218 wake_up_interruptible(&info->open_wait);
1222 * ------------------------------------------------------------
1223 * rs_open() and friends
1224 * ------------------------------------------------------------
1226 static int block_til_ready(struct tty_struct *tty, struct file * filp,
1227 struct m68k_serial *info)
1229 DECLARE_WAITQUEUE(wait, current);
1234 * If the device is in the middle of being closed, then block
1235 * until it's done, and then try again.
1237 if (info->flags & S_CLOSING) {
1238 interruptible_sleep_on(&info->close_wait);
1239 #ifdef SERIAL_DO_RESTART
1240 if (info->flags & S_HUP_NOTIFY)
1243 return -ERESTARTSYS;
1250 * If non-blocking mode is set, or the port is not enabled,
1251 * then make the check up front and then exit.
1253 if ((filp->f_flags & O_NONBLOCK) ||
1254 (tty->flags & (1 << TTY_IO_ERROR))) {
1255 info->flags |= S_NORMAL_ACTIVE;
1259 if (tty->termios->c_cflag & CLOCAL)
1263 * Block waiting for the carrier detect and the line to become
1264 * free (i.e., not in use by the callout). While we are in
1265 * this loop, info->count is dropped by one, so that
1266 * rs_close() knows when to free things. We restore it upon
1267 * exit, either normal or abnormal.
1270 add_wait_queue(&info->open_wait, &wait);
1273 info->blocked_open++;
1276 m68k_rtsdtr(info, 1);
1278 current->state = TASK_INTERRUPTIBLE;
1279 if (tty_hung_up_p(filp) ||
1280 !(info->flags & S_INITIALIZED)) {
1281 #ifdef SERIAL_DO_RESTART
1282 if (info->flags & S_HUP_NOTIFY)
1285 retval = -ERESTARTSYS;
1291 if (!(info->flags & S_CLOSING) && do_clocal)
1293 if (signal_pending(current)) {
1294 retval = -ERESTARTSYS;
1299 current->state = TASK_RUNNING;
1300 remove_wait_queue(&info->open_wait, &wait);
1301 if (!tty_hung_up_p(filp))
1303 info->blocked_open--;
1307 info->flags |= S_NORMAL_ACTIVE;
1312 * This routine is called whenever a serial port is opened. It
1313 * enables interrupts for a serial port, linking in its S structure into
1314 * the IRQ chain. It also performs the serial-specific
1315 * initialization for the tty structure.
1317 int rs_open(struct tty_struct *tty, struct file * filp)
1319 struct m68k_serial *info;
1324 if (line >= NR_PORTS || line < 0) /* we have exactly one */
1327 info = &m68k_soft[line];
1329 if (serial_paranoia_check(info, tty->name, "rs_open"))
1333 tty->driver_data = info;
1337 * Start up serial port
1339 retval = startup(info);
1343 return block_til_ready(tty, filp, info);
1346 /* Finally, routines used to initialize the serial driver. */
1348 static void show_serial_version(void)
1350 printk("MC68328 serial driver version 1.00\n");
1354 /* Serial Power management
1355 * The console (currently fixed at line 0) is a special case for power
1356 * management because the kernel is so chatty. The console will be
1357 * explicitly disabled my our power manager as the last minute, so we won't
1358 * mess with it here.
1360 static struct pm_dev *serial_pm[NR_PORTS];
1362 static int serial_pm_callback(struct pm_dev *dev, pm_request_t request, void *data)
1364 struct m68k_serial *info = (struct m68k_serial *)dev->data;
1369 /* special case for line 0 - pm restores it */
1385 void shutdown_console(void)
1387 struct m68k_serial *info = &m68k_soft[0];
1389 /* HACK: wait a bit for any pending printk's to be dumped */
1398 void startup_console(void)
1400 struct m68k_serial *info = &m68k_soft[0];
1406 static struct tty_operations rs_ops = {
1410 .flush_chars = rs_flush_chars,
1411 .write_room = rs_write_room,
1412 .chars_in_buffer = rs_chars_in_buffer,
1413 .flush_buffer = rs_flush_buffer,
1415 .throttle = rs_throttle,
1416 .unthrottle = rs_unthrottle,
1417 .set_termios = rs_set_termios,
1420 .hangup = rs_hangup,
1421 .set_ldisc = rs_set_ldisc,
1424 /* rs_init inits the driver */
1429 struct m68k_serial *info;
1431 serial_driver = alloc_tty_driver(NR_PORTS);
1435 show_serial_version();
1437 /* Initialize the tty_driver structure */
1438 /* SPARC: Not all of this is exactly right for us. */
1440 serial_driver->name = "ttyS";
1441 serial_driver->major = TTY_MAJOR;
1442 serial_driver->minor_start = 64;
1443 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1444 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1445 serial_driver->init_termios = tty_std_termios;
1446 serial_driver->init_termios.c_cflag =
1447 m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL;
1448 serial_driver->flags = TTY_DRIVER_REAL_RAW;
1449 tty_set_operations(serial_driver, &rs_ops);
1451 if (tty_register_driver(serial_driver)) {
1452 put_tty_driver(serial_driver);
1453 printk(KERN_ERR "Couldn't register serial driver\n");
1457 save_flags(flags); cli();
1459 for(i=0;i<NR_PORTS;i++) {
1461 info = &m68k_soft[i];
1462 info->magic = SERIAL_MAGIC;
1463 info->port = (int) &uart_addr[i];
1465 info->irq = uart_irqs[i];
1466 info->custom_divisor = 16;
1467 info->close_delay = 50;
1468 info->closing_wait = 3000;
1472 info->blocked_open = 0;
1473 INIT_WORK(&info->tqueue, do_softint, info);
1474 INIT_WORK(&info->tqueue_hangup, do_serial_hangup, info);
1475 init_waitqueue_head(&info->open_wait);
1476 init_waitqueue_head(&info->close_wait);
1478 info->is_cons = 1; /* Means shortcuts work */
1480 printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line,
1481 info->port, info->irq);
1482 printk(" is a builtin MC68328 UART\n");
1484 IRQ_ports[info->irq] = info; /* waste of space */
1486 #ifdef CONFIG_M68VZ328
1488 PJSEL &= 0xCF; /* PSW enable second port output */
1491 if (request_irq(uart_irqs[i],
1494 "M68328_UART", NULL))
1495 panic("Unable to attach 68328 serial interrupt\n");
1497 serial_pm[i] = pm_register(PM_SYS_DEV, PM_SYS_COM, serial_pm_callback);
1499 serial_pm[i]->data = info;
1502 restore_flags(flags);
1509 * register_serial and unregister_serial allows for serial ports to be
1510 * configured at run-time, to support PCMCIA modems.
1512 /* SPARC: Unused at this time, just here to make things link. */
1513 int register_serial(struct serial_struct *req)
1518 void unregister_serial(int line)
1523 module_init(rs68328_init);
1527 static void m68328_set_baud(void)
1529 unsigned short ustcnt;
1533 USTCNT = ustcnt & ~USTCNT_TXEN;
1536 for (i = 0; i < sizeof(baud_table) / sizeof(baud_table[0]); i++)
1537 if (baud_table[i] == m68328_console_baud)
1539 if (i >= sizeof(baud_table) / sizeof(baud_table[0])) {
1540 m68328_console_baud = 9600;
1544 UBAUD = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
1545 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
1546 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
1547 ustcnt |= USTCNT_8_7;
1548 ustcnt |= USTCNT_TXEN;
1550 m68328_console_initted = 1;
1555 int m68328_console_setup(struct console *cp, char *arg)
1557 int i, n = CONSOLE_BAUD_RATE;
1563 n = simple_strtoul(arg,NULL,0);
1565 for (i = 0; i < BAUD_TABLE_SIZE; i++)
1566 if (baud_table[i] == n)
1568 if (i < BAUD_TABLE_SIZE) {
1569 m68328_console_baud = n;
1570 m68328_console_cbaud = 0;
1572 m68328_console_cbaud |= CBAUDEX;
1575 m68328_console_cbaud |= i;
1578 m68328_set_baud(); /* make sure baud rate changes */
1583 static struct tty_driver *m68328_console_device(struct console *c, int *index)
1586 return serial_driver;
1590 void m68328_console_write (struct console *co, const char *str,
1593 if (!m68328_console_initted)
1598 rs_put_char( *str++ );
1603 static struct console m68328_driver = {
1605 .write = m68328_console_write,
1606 .device = m68328_console_device,
1607 .setup = m68328_console_setup,
1608 .flags = CON_PRINTBUFFER,
1613 static int __init m68328_console_init(void)
1615 register_console(&m68328_driver);
1619 console_initcall(m68328_console_init);