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>
40 #include <asm/system.h>
41 #include <asm/segment.h>
42 #include <asm/bitops.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 #include "68328serial.h"
62 /* Turn off usage of real serial interrupt code, to "support" Copilot */
63 #ifdef CONFIG_XCOPILOT_BUGS
69 static struct m68k_serial m68k_soft[NR_PORTS];
70 struct m68k_serial *IRQ_ports[NR_IRQS];
72 static unsigned int uart_irqs[NR_PORTS] = UART_IRQ_DEFNS;
74 /* multiple ports are contiguous in memory */
75 m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
77 struct tty_struct m68k_ttys;
78 struct m68k_serial *m68k_consinfo = 0;
80 #define M68K_CLOCK (16667000) /* FIXME: 16MHz is likely wrong */
83 extern wait_queue_head_t keypress_wait;
86 struct tty_driver *serial_driver;
88 /* serial subtype definitions */
89 #define SERIAL_TYPE_NORMAL 1
91 /* number of characters left in xmit buffer before we ask for more */
92 #define WAKEUP_CHARS 256
94 /* Debugging... DEBUG_INTR is bad to use when one of the zs
95 * lines is your console ;(
97 #undef SERIAL_DEBUG_INTR
98 #undef SERIAL_DEBUG_OPEN
99 #undef SERIAL_DEBUG_FLOW
101 #define RS_ISR_PASS_LIMIT 256
103 #define _INLINE_ inline
105 static void change_speed(struct m68k_serial *info);
108 * Setup for console. Argument comes from the boot command line.
111 #if defined(CONFIG_M68EZ328ADS) || defined(CONFIG_ALMA_ANS) || defined(CONFIG_DRAGONIXVZ)
112 #define CONSOLE_BAUD_RATE 115200
113 #define DEFAULT_CBAUD B115200
116 /* note: this is messy, but it works, again, perhaps defined somewhere else?*/
117 #ifdef CONFIG_M68VZ328
118 #define CONSOLE_BAUD_RATE 19200
119 #define DEFAULT_CBAUD B19200
124 #ifndef CONSOLE_BAUD_RATE
125 #define CONSOLE_BAUD_RATE 9600
126 #define DEFAULT_CBAUD B9600
130 static int m68328_console_initted = 0;
131 static int m68328_console_baud = CONSOLE_BAUD_RATE;
132 static int m68328_console_cbaud = DEFAULT_CBAUD;
136 * tmp_buf is used as a temporary buffer by serial_write. We need to
137 * lock it in case the memcpy_fromfs blocks while swapping in a page,
138 * and some other program tries to do a serial write at the same time.
139 * Since the lock will only come under contention when the system is
140 * swapping and available memory is low, it makes sense to share one
141 * buffer across all the serial ports, since it significantly saves
142 * memory if large numbers of serial ports are open.
144 static unsigned char tmp_buf[SERIAL_XMIT_SIZE]; /* This is cheating */
145 DECLARE_MUTEX(tmp_buf_sem);
147 static inline int serial_paranoia_check(struct m68k_serial *info,
148 char *name, const char *routine)
150 #ifdef SERIAL_PARANOIA_CHECK
151 static const char *badmagic =
152 "Warning: bad magic number for serial struct %s in %s\n";
153 static const char *badinfo =
154 "Warning: null m68k_serial for %s in %s\n";
157 printk(badinfo, name, routine);
160 if (info->magic != SERIAL_MAGIC) {
161 printk(badmagic, name, routine);
169 * This is used to figure out the divisor speeds and the timeouts
171 static int baud_table[] = {
172 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
173 9600, 19200, 38400, 57600, 115200, 0 };
175 #define BAUD_TABLE_SIZE (sizeof(baud_table)/sizeof(baud_table[0]))
177 /* Sets or clears DTR/RTS on the requested line */
178 static inline void m68k_rtsdtr(struct m68k_serial *ss, int set)
181 /* set the RTS/CTS line */
188 /* Utility routines */
189 static inline int get_baud(struct m68k_serial *ss)
191 unsigned long result = 115200;
192 unsigned short int baud = uart_addr[ss->line].ubaud;
193 if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400;
194 result >>= GET_FIELD(baud, UBAUD_DIVIDE);
200 * ------------------------------------------------------------
201 * rs_stop() and rs_start()
203 * This routines are called before setting or resetting tty->stopped.
204 * They enable or disable transmitter interrupts, as necessary.
205 * ------------------------------------------------------------
207 static void rs_stop(struct tty_struct *tty)
209 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
210 m68328_uart *uart = &uart_addr[info->line];
213 if (serial_paranoia_check(info, tty->name, "rs_stop"))
216 save_flags(flags); cli();
217 uart->ustcnt &= ~USTCNT_TXEN;
218 restore_flags(flags);
221 static void rs_put_char(char ch)
223 int flags, loops = 0;
225 save_flags(flags); cli();
227 while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
234 restore_flags(flags);
237 static void rs_start(struct tty_struct *tty)
239 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
240 m68328_uart *uart = &uart_addr[info->line];
243 if (serial_paranoia_check(info, tty->name, "rs_start"))
246 save_flags(flags); cli();
247 if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
249 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
251 uart->ustcnt |= USTCNT_TXEN;
254 restore_flags(flags);
257 /* Drop into either the boot monitor or kadb upon receiving a break
258 * from keyboard/console input.
260 static void batten_down_hatches(void)
262 /* Drop into the debugger */
265 static _INLINE_ void status_handle(struct m68k_serial *info, unsigned short status)
269 if((info->tty->termios->c_cflag & CRTSCTS) &&
270 ((info->curregs[3] & AUTO_ENAB)==0)) {
271 info->curregs[3] |= AUTO_ENAB;
272 info->pendregs[3] |= AUTO_ENAB;
273 write_zsreg(info->m68k_channel, 3, info->curregs[3]);
276 if((info->curregs[3] & AUTO_ENAB)) {
277 info->curregs[3] &= ~AUTO_ENAB;
278 info->pendregs[3] &= ~AUTO_ENAB;
279 write_zsreg(info->m68k_channel, 3, info->curregs[3]);
283 /* If this is console input and this is a
284 * 'break asserted' status change interrupt
285 * see if we can drop into the debugger
287 if((status & URX_BREAK) && info->break_abort)
288 batten_down_hatches();
292 static _INLINE_ void receive_chars(struct m68k_serial *info, struct pt_regs *regs, unsigned short rx)
294 struct tty_struct *tty = info->tty;
295 m68328_uart *uart = &uart_addr[info->line];
299 * This do { } while() loop will get ALL chars out of Rx FIFO
301 #ifndef CONFIG_XCOPILOT_BUGS
304 ch = GET_FIELD(rx, URX_RXDATA);
307 if(URX_BREAK & rx) { /* whee, break received */
308 status_handle(info, rx);
310 #ifdef CONFIG_MAGIC_SYSRQ
311 } else if (ch == 0x10) { /* ^P */
315 /* show_net_buffers(); */
317 } else if (ch == 0x12) { /* ^R */
318 machine_restart(NULL);
320 #endif /* CONFIG_MAGIC_SYSRQ */
322 /* It is a 'keyboard interrupt' ;-) */
323 #ifdef CONFIG_CONSOLE
324 wake_up(&keypress_wait);
332 * Make sure that we do not overflow the buffer
334 if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
335 schedule_work(&tty->flip.work);
339 if(rx & URX_PARITY_ERROR) {
340 *tty->flip.flag_buf_ptr++ = TTY_PARITY;
341 status_handle(info, rx);
342 } else if(rx & URX_OVRUN) {
343 *tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
344 status_handle(info, rx);
345 } else if(rx & URX_FRAME_ERROR) {
346 *tty->flip.flag_buf_ptr++ = TTY_FRAME;
347 status_handle(info, rx);
349 *tty->flip.flag_buf_ptr++ = 0; /* XXX */
351 *tty->flip.char_buf_ptr++ = ch;
354 #ifndef CONFIG_XCOPILOT_BUGS
355 } while((rx = uart->urx.w) & URX_DATA_READY);
358 schedule_work(&tty->flip.work);
364 static _INLINE_ void transmit_chars(struct m68k_serial *info)
366 m68328_uart *uart = &uart_addr[info->line];
370 uart->utx.b.txdata = info->x_char;
372 goto clear_and_return;
375 if((info->xmit_cnt <= 0) || info->tty->stopped) {
376 /* That's peculiar... TX ints off */
377 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
378 goto clear_and_return;
382 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
383 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
386 if (info->xmit_cnt < WAKEUP_CHARS)
387 schedule_work(&info->tqueue);
389 if(info->xmit_cnt <= 0) {
390 /* All done for now... TX ints off */
391 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
392 goto clear_and_return;
396 /* Clear interrupt (should be auto)*/
401 * This is the serial driver's generic interrupt routine
403 irqreturn_t rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
405 struct m68k_serial * info;
410 info = IRQ_ports[irq];
414 uart = &uart_addr[info->line];
420 if (rx & URX_DATA_READY) receive_chars(info, regs, rx);
421 if (tx & UTX_TX_AVAIL) transmit_chars(info);
423 receive_chars(info, regs, rx);
428 static void do_softint(void *private)
430 struct m68k_serial *info = (struct m68k_serial *) private;
431 struct tty_struct *tty;
437 if (clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
438 if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
439 tty->ldisc.write_wakeup)
440 (tty->ldisc.write_wakeup)(tty);
441 wake_up_interruptible(&tty->write_wait);
447 * This routine is called from the scheduler tqueue when the interrupt
448 * routine has signalled that a hangup has occurred. The path of
449 * hangup processing is:
451 * serial interrupt routine -> (scheduler tqueue) ->
452 * do_serial_hangup() -> tty->hangup() -> rs_hangup()
455 static void do_serial_hangup(void *private)
457 struct m68k_serial *info = (struct m68k_serial *) private;
458 struct tty_struct *tty;
468 static int startup(struct m68k_serial * info)
470 m68328_uart *uart = &uart_addr[info->line];
473 if (info->flags & S_INITIALIZED)
476 if (!info->xmit_buf) {
477 info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL);
482 save_flags(flags); cli();
485 * Clear the FIFO buffers and disable them
486 * (they will be reenabled in change_speed())
489 uart->ustcnt = USTCNT_UEN;
490 info->xmit_fifo_size = 1;
491 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN;
495 * Finally, enable sequencing and interrupts
498 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN |
499 USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK;
501 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK;
505 clear_bit(TTY_IO_ERROR, &info->tty->flags);
506 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
509 * and set the speed of the serial port
514 info->flags |= S_INITIALIZED;
515 restore_flags(flags);
520 * This routine will shutdown a serial port; interrupts are disabled, and
521 * DTR is dropped if the hangup on close termio flag is on.
523 static void shutdown(struct m68k_serial * info)
525 m68328_uart *uart = &uart_addr[info->line];
528 uart->ustcnt = 0; /* All off! */
529 if (!(info->flags & S_INITIALIZED))
532 save_flags(flags); cli(); /* Disable interrupts */
534 if (info->xmit_buf) {
535 free_page((unsigned long) info->xmit_buf);
540 set_bit(TTY_IO_ERROR, &info->tty->flags);
542 info->flags &= ~S_INITIALIZED;
543 restore_flags(flags);
547 int divisor, prescale;
549 #ifndef CONFIG_M68VZ328
550 hw_baud_table[18] = {
565 {1,0x26}, /* 19200 */
566 {0,0x26}, /* 38400 */
567 {1,0x38}, /* 57600 */
568 {0,0x38}, /* 115200 */
571 hw_baud_table[18] = {
586 {2,0x26}, /* 19200 */
587 {1,0x26}, /* 38400 */
588 {0,0x26}, /* 57600 */
589 {1,0x38}, /* 115200 */
592 /* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
595 * This routine is called to set the UART divisor registers to match
596 * the specified baud rate for a serial port.
598 static void change_speed(struct m68k_serial *info)
600 m68328_uart *uart = &uart_addr[info->line];
602 unsigned short ustcnt;
606 if (!info->tty || !info->tty->termios)
608 cflag = info->tty->termios->c_cflag;
609 if (!(port = info->port))
612 ustcnt = uart->ustcnt;
613 uart->ustcnt = ustcnt & ~USTCNT_TXEN;
617 i = (i & ~CBAUDEX) + B38400;
620 info->baud = baud_table[i];
621 uart->ubaud = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
622 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
624 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
626 if ((cflag & CSIZE) == CS8)
627 ustcnt |= USTCNT_8_7;
630 ustcnt |= USTCNT_STOP;
633 ustcnt |= USTCNT_PARITYEN;
635 ustcnt |= USTCNT_ODD_EVEN;
637 #ifdef CONFIG_SERIAL_68328_RTS_CTS
638 if (cflag & CRTSCTS) {
639 uart->utx.w &= ~ UTX_NOCTS;
641 uart->utx.w |= UTX_NOCTS;
645 ustcnt |= USTCNT_TXEN;
647 uart->ustcnt = ustcnt;
652 * Fair output driver allows a process to speak.
654 static void rs_fair_output(void)
656 int left; /* Output no more than that */
658 struct m68k_serial *info = &m68k_soft[0];
661 if (info == 0) return;
662 if (info->xmit_buf == 0) return;
664 save_flags(flags); cli();
665 left = info->xmit_cnt;
667 c = info->xmit_buf[info->xmit_tail];
668 info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
670 restore_flags(flags);
674 save_flags(flags); cli();
675 left = min(info->xmit_cnt, left-1);
678 /* Last character is being transmitted now (hopefully). */
681 restore_flags(flags);
686 * m68k_console_print is registered for printk.
688 void console_print_68328(const char *p)
692 while((c=*(p++)) != 0) {
698 /* Comment this if you want to have a strict interrupt-driven output */
704 static void rs_set_ldisc(struct tty_struct *tty)
706 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
708 if (serial_paranoia_check(info, tty->name, "rs_set_ldisc"))
711 info->is_cons = (tty->termios->c_line == N_TTY);
713 printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
716 static void rs_flush_chars(struct tty_struct *tty)
718 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
719 m68328_uart *uart = &uart_addr[info->line];
722 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
728 /* Enable transmitter */
729 save_flags(flags); cli();
731 if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
733 restore_flags(flags);
738 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
740 uart->ustcnt |= USTCNT_TXEN;
744 if (uart->utx.w & UTX_TX_AVAIL) {
749 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
750 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
755 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
758 restore_flags(flags);
761 extern void console_printn(const char * b, int count);
763 static int rs_write(struct tty_struct * tty, int from_user,
764 const unsigned char *buf, int count)
767 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
768 m68328_uart *uart = &uart_addr[info->line];
771 if (serial_paranoia_check(info, tty->name, "rs_write"))
774 if (!tty || !info->xmit_buf)
780 c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
781 SERIAL_XMIT_SIZE - info->xmit_head));
787 copy_from_user(tmp_buf, buf, c);
788 c = min_t(int, c, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
789 SERIAL_XMIT_SIZE - info->xmit_head));
790 memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
793 memcpy(info->xmit_buf + info->xmit_head, buf, c);
794 info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
796 restore_flags(flags);
802 if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
803 /* Enable transmitter */
806 while(info->xmit_cnt) {
809 uart->ustcnt |= USTCNT_TXEN;
811 uart->ustcnt |= USTCNT_TX_INTR_MASK;
813 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
815 if (uart->utx.w & UTX_TX_AVAIL) {
816 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
817 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
824 restore_flags(flags);
826 restore_flags(flags);
830 static int rs_write_room(struct tty_struct *tty)
832 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
835 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
837 ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
843 static int rs_chars_in_buffer(struct tty_struct *tty)
845 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
847 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
849 return info->xmit_cnt;
852 static void rs_flush_buffer(struct tty_struct *tty)
854 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
856 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
859 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
861 wake_up_interruptible(&tty->write_wait);
862 if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
863 tty->ldisc.write_wakeup)
864 (tty->ldisc.write_wakeup)(tty);
868 * ------------------------------------------------------------
871 * This routine is called by the upper-layer tty layer to signal that
872 * incoming characters should be throttled.
873 * ------------------------------------------------------------
875 static void rs_throttle(struct tty_struct * tty)
877 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
879 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
883 info->x_char = STOP_CHAR(tty);
885 /* Turn off RTS line (do this atomic) */
888 static void rs_unthrottle(struct tty_struct * tty)
890 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
892 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
899 info->x_char = START_CHAR(tty);
902 /* Assert RTS line (do this atomic) */
906 * ------------------------------------------------------------
907 * rs_ioctl() and friends
908 * ------------------------------------------------------------
911 static int get_serial_info(struct m68k_serial * info,
912 struct serial_struct * retinfo)
914 struct serial_struct tmp;
918 memset(&tmp, 0, sizeof(tmp));
919 tmp.type = info->type;
920 tmp.line = info->line;
921 tmp.port = info->port;
923 tmp.flags = info->flags;
924 tmp.baud_base = info->baud_base;
925 tmp.close_delay = info->close_delay;
926 tmp.closing_wait = info->closing_wait;
927 tmp.custom_divisor = info->custom_divisor;
928 copy_to_user(retinfo,&tmp,sizeof(*retinfo));
932 static int set_serial_info(struct m68k_serial * info,
933 struct serial_struct * new_info)
935 struct serial_struct new_serial;
936 struct m68k_serial old_info;
941 copy_from_user(&new_serial,new_info,sizeof(new_serial));
944 if (!capable(CAP_SYS_ADMIN)) {
945 if ((new_serial.baud_base != info->baud_base) ||
946 (new_serial.type != info->type) ||
947 (new_serial.close_delay != info->close_delay) ||
948 ((new_serial.flags & ~S_USR_MASK) !=
949 (info->flags & ~S_USR_MASK)))
951 info->flags = ((info->flags & ~S_USR_MASK) |
952 (new_serial.flags & S_USR_MASK));
953 info->custom_divisor = new_serial.custom_divisor;
961 * OK, past this point, all the error checking has been done.
962 * At this point, we start making changes.....
965 info->baud_base = new_serial.baud_base;
966 info->flags = ((info->flags & ~S_FLAGS) |
967 (new_serial.flags & S_FLAGS));
968 info->type = new_serial.type;
969 info->close_delay = new_serial.close_delay;
970 info->closing_wait = new_serial.closing_wait;
973 retval = startup(info);
978 * get_lsr_info - get line status register info
980 * Purpose: Let user call ioctl() to get info when the UART physically
981 * is emptied. On bus types like RS485, the transmitter must
982 * release the bus after transmitting. This must be done when
983 * the transmit shift register is empty, not be done when the
984 * transmit holding register is empty. This functionality
985 * allows an RS485 driver to be written in user space.
987 static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
989 #ifdef CONFIG_SERIAL_68328_RTS_CTS
990 m68328_uart *uart = &uart_addr[info->line];
992 unsigned char status;
995 #ifdef CONFIG_SERIAL_68328_RTS_CTS
996 status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
1001 put_user(status,value);
1006 * This routine sends a break character out the serial port.
1008 static void send_break( struct m68k_serial * info, int duration)
1010 m68328_uart *uart = &uart_addr[info->line];
1011 unsigned long flags;
1014 current->state = TASK_INTERRUPTIBLE;
1018 uart->utx.w |= UTX_SEND_BREAK;
1019 schedule_timeout(duration);
1020 uart->utx.w &= ~UTX_SEND_BREAK;
1022 restore_flags(flags);
1025 static int rs_ioctl(struct tty_struct *tty, struct file * file,
1026 unsigned int cmd, unsigned long arg)
1029 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1032 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1035 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1036 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
1037 (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
1038 if (tty->flags & (1 << TTY_IO_ERROR))
1043 case TCSBRK: /* SVID version: non-zero arg --> no break */
1044 retval = tty_check_change(tty);
1047 tty_wait_until_sent(tty, 0);
1049 send_break(info, HZ/4); /* 1/4 second */
1051 case TCSBRKP: /* support for POSIX tcsendbreak() */
1052 retval = tty_check_change(tty);
1055 tty_wait_until_sent(tty, 0);
1056 send_break(info, arg ? arg*(HZ/10) : HZ/4);
1059 error = put_user(C_CLOCAL(tty) ? 1 : 0,
1060 (unsigned long *) arg);
1065 get_user(arg, (unsigned long *) arg);
1066 tty->termios->c_cflag =
1067 ((tty->termios->c_cflag & ~CLOCAL) |
1068 (arg ? CLOCAL : 0));
1071 error = verify_area(VERIFY_WRITE, (void *) arg,
1072 sizeof(struct serial_struct));
1075 return get_serial_info(info,
1076 (struct serial_struct *) arg);
1078 return set_serial_info(info,
1079 (struct serial_struct *) arg);
1080 case TIOCSERGETLSR: /* Get line status register */
1081 error = verify_area(VERIFY_WRITE, (void *) arg,
1082 sizeof(unsigned int));
1086 return get_lsr_info(info, (unsigned int *) arg);
1088 case TIOCSERGSTRUCT:
1089 error = verify_area(VERIFY_WRITE, (void *) arg,
1090 sizeof(struct m68k_serial));
1093 copy_to_user((struct m68k_serial *) arg,
1094 info, sizeof(struct m68k_serial));
1098 return -ENOIOCTLCMD;
1103 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
1105 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
1107 if (tty->termios->c_cflag == old_termios->c_cflag)
1112 if ((old_termios->c_cflag & CRTSCTS) &&
1113 !(tty->termios->c_cflag & CRTSCTS)) {
1114 tty->hw_stopped = 0;
1121 * ------------------------------------------------------------
1124 * This routine is called when the serial port gets closed. First, we
1125 * wait for the last remaining data to be sent. Then, we unlink its
1126 * S structure from the interrupt chain if necessary, and we free
1127 * that IRQ if nothing is left in the chain.
1128 * ------------------------------------------------------------
1130 static void rs_close(struct tty_struct *tty, struct file * filp)
1132 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1133 m68328_uart *uart = &uart_addr[info->line];
1134 unsigned long flags;
1136 if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1139 save_flags(flags); cli();
1141 if (tty_hung_up_p(filp)) {
1142 restore_flags(flags);
1146 if ((tty->count == 1) && (info->count != 1)) {
1148 * Uh, oh. tty->count is 1, which means that the tty
1149 * structure will be freed. Info->count should always
1150 * be one in these conditions. If it's greater than
1151 * one, we've got real problems, since it means the
1152 * serial port won't be shutdown.
1154 printk("rs_close: bad serial port count; tty->count is 1, "
1155 "info->count is %d\n", info->count);
1158 if (--info->count < 0) {
1159 printk("rs_close: bad serial port count for ttyS%d: %d\n",
1160 info->line, info->count);
1164 restore_flags(flags);
1167 info->flags |= S_CLOSING;
1169 * Now we wait for the transmit buffer to clear; and we notify
1170 * the line discipline to only process XON/XOFF characters.
1173 if (info->closing_wait != S_CLOSING_WAIT_NONE)
1174 tty_wait_until_sent(tty, info->closing_wait);
1176 * At this point we stop accepting input. To do this, we
1177 * disable the receive line status interrupts, and tell the
1178 * interrupt driver to stop checking the data ready bit in the
1179 * line status register.
1182 uart->ustcnt &= ~USTCNT_RXEN;
1183 uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
1186 if (tty->driver->flush_buffer)
1187 tty->driver->flush_buffer(tty);
1188 if (tty->ldisc.flush_buffer)
1189 tty->ldisc.flush_buffer(tty);
1193 if (tty->ldisc.num != ldiscs[N_TTY].num) {
1194 if (tty->ldisc.close)
1195 (tty->ldisc.close)(tty);
1196 tty->ldisc = ldiscs[N_TTY];
1197 tty->termios->c_line = N_TTY;
1198 if (tty->ldisc.open)
1199 (tty->ldisc.open)(tty);
1201 if (info->blocked_open) {
1202 if (info->close_delay) {
1203 current->state = TASK_INTERRUPTIBLE;
1204 schedule_timeout(info->close_delay);
1206 wake_up_interruptible(&info->open_wait);
1208 info->flags &= ~(S_NORMAL_ACTIVE|S_CLOSING);
1209 wake_up_interruptible(&info->close_wait);
1210 restore_flags(flags);
1214 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1216 void rs_hangup(struct tty_struct *tty)
1218 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1220 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1223 rs_flush_buffer(tty);
1227 info->flags &= ~S_NORMAL_ACTIVE;
1229 wake_up_interruptible(&info->open_wait);
1233 * ------------------------------------------------------------
1234 * rs_open() and friends
1235 * ------------------------------------------------------------
1237 static int block_til_ready(struct tty_struct *tty, struct file * filp,
1238 struct m68k_serial *info)
1240 DECLARE_WAITQUEUE(wait, current);
1245 * If the device is in the middle of being closed, then block
1246 * until it's done, and then try again.
1248 if (info->flags & S_CLOSING) {
1249 interruptible_sleep_on(&info->close_wait);
1250 #ifdef SERIAL_DO_RESTART
1251 if (info->flags & S_HUP_NOTIFY)
1254 return -ERESTARTSYS;
1261 * If non-blocking mode is set, or the port is not enabled,
1262 * then make the check up front and then exit.
1264 if ((filp->f_flags & O_NONBLOCK) ||
1265 (tty->flags & (1 << TTY_IO_ERROR))) {
1266 info->flags |= S_NORMAL_ACTIVE;
1270 if (tty->termios->c_cflag & CLOCAL)
1274 * Block waiting for the carrier detect and the line to become
1275 * free (i.e., not in use by the callout). While we are in
1276 * this loop, info->count is dropped by one, so that
1277 * rs_close() knows when to free things. We restore it upon
1278 * exit, either normal or abnormal.
1281 add_wait_queue(&info->open_wait, &wait);
1284 info->blocked_open++;
1287 m68k_rtsdtr(info, 1);
1289 current->state = TASK_INTERRUPTIBLE;
1290 if (tty_hung_up_p(filp) ||
1291 !(info->flags & S_INITIALIZED)) {
1292 #ifdef SERIAL_DO_RESTART
1293 if (info->flags & S_HUP_NOTIFY)
1296 retval = -ERESTARTSYS;
1302 if (!(info->flags & S_CLOSING) && do_clocal)
1304 if (signal_pending(current)) {
1305 retval = -ERESTARTSYS;
1310 current->state = TASK_RUNNING;
1311 remove_wait_queue(&info->open_wait, &wait);
1312 if (!tty_hung_up_p(filp))
1314 info->blocked_open--;
1318 info->flags |= S_NORMAL_ACTIVE;
1323 * This routine is called whenever a serial port is opened. It
1324 * enables interrupts for a serial port, linking in its S structure into
1325 * the IRQ chain. It also performs the serial-specific
1326 * initialization for the tty structure.
1328 int rs_open(struct tty_struct *tty, struct file * filp)
1330 struct m68k_serial *info;
1335 if (line >= NR_PORTS || line < 0) /* we have exactly one */
1338 info = &m68k_soft[line];
1340 if (serial_paranoia_check(info, tty->name, "rs_open"))
1344 tty->driver_data = info;
1348 * Start up serial port
1350 retval = startup(info);
1354 return block_til_ready(tty, filp, info);
1357 /* Finally, routines used to initialize the serial driver. */
1359 static void show_serial_version(void)
1361 printk("MC68328 serial driver version 1.00\n");
1365 /* Serial Power management
1366 * The console (currently fixed at line 0) is a special case for power
1367 * management because the kernel is so chatty. The console will be
1368 * explicitly disabled my our power manager as the last minute, so we won't
1369 * mess with it here.
1371 static struct pm_dev *serial_pm[NR_PORTS];
1373 static int serial_pm_callback(struct pm_dev *dev, pm_request_t request, void *data)
1375 struct m68k_serial *info = (struct m68k_serial *)dev->data;
1380 /* special case for line 0 - pm restores it */
1396 void shutdown_console(void)
1398 struct m68k_serial *info = &m68k_soft[0];
1400 /* HACK: wait a bit for any pending printk's to be dumped */
1409 void startup_console(void)
1411 struct m68k_serial *info = &m68k_soft[0];
1417 static struct tty_operations rs_ops = {
1421 .flush_chars = rs_flush_chars,
1422 .write_room = rs_write_room,
1423 .chars_in_buffer = rs_chars_in_buffer,
1424 .flush_buffer = rs_flush_buffer,
1426 .throttle = rs_throttle,
1427 .unthrottle = rs_unthrottle,
1428 .set_termios = rs_set_termios,
1431 .hangup = rs_hangup,
1432 .set_ldisc = rs_set_ldisc,
1435 /* rs_init inits the driver */
1440 struct m68k_serial *info;
1442 serial_driver = alloc_tty_driver(NR_PORTS);
1446 show_serial_version();
1448 /* Initialize the tty_driver structure */
1449 /* SPARC: Not all of this is exactly right for us. */
1451 serial_driver->name = "ttyS";
1452 serial_driver->major = TTY_MAJOR;
1453 serial_driver->minor_start = 64;
1454 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1455 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1456 serial_driver->init_termios = tty_std_termios;
1457 serial_driver->init_termios.c_cflag =
1458 m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL;
1459 serial_driver->flags = TTY_DRIVER_REAL_RAW;
1460 tty_set_operations(serial_driver, &rs_ops);
1462 if (tty_register_driver(serial_driver)) {
1463 put_tty_driver(serial_driver);
1464 printk(KERN_ERR "Couldn't register serial driver\n");
1468 save_flags(flags); cli();
1470 for(i=0;i<NR_PORTS;i++) {
1472 info = &m68k_soft[i];
1473 info->magic = SERIAL_MAGIC;
1474 info->port = (int) &uart_addr[i];
1476 info->irq = uart_irqs[i];
1477 info->custom_divisor = 16;
1478 info->close_delay = 50;
1479 info->closing_wait = 3000;
1483 info->blocked_open = 0;
1484 INIT_WORK(&info->tqueue, do_softint, info);
1485 INIT_WORK(&info->tqueue_hangup, do_serial_hangup, info);
1486 init_waitqueue_head(&info->open_wait);
1487 init_waitqueue_head(&info->close_wait);
1489 info->is_cons = 1; /* Means shortcuts work */
1491 printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line,
1492 info->port, info->irq);
1493 printk(" is a builtin MC68328 UART\n");
1495 IRQ_ports[info->irq] = info; /* waste of space */
1497 #ifdef CONFIG_M68VZ328
1499 PJSEL &= 0xCF; /* PSW enable second port output */
1502 if (request_irq(uart_irqs[i],
1505 "M68328_UART", NULL))
1506 panic("Unable to attach 68328 serial interrupt\n");
1508 serial_pm[i] = pm_register(PM_SYS_DEV, PM_SYS_COM, serial_pm_callback);
1510 serial_pm[i]->data = info;
1513 restore_flags(flags);
1520 * register_serial and unregister_serial allows for serial ports to be
1521 * configured at run-time, to support PCMCIA modems.
1523 /* SPARC: Unused at this time, just here to make things link. */
1524 int register_serial(struct serial_struct *req)
1529 void unregister_serial(int line)
1534 module_init(rs68328_init);
1538 static void m68328_set_baud(void)
1540 unsigned short ustcnt;
1544 USTCNT = ustcnt & ~USTCNT_TXEN;
1547 for (i = 0; i < sizeof(baud_table) / sizeof(baud_table[0]); i++)
1548 if (baud_table[i] == m68328_console_baud)
1550 if (i >= sizeof(baud_table) / sizeof(baud_table[0])) {
1551 m68328_console_baud = 9600;
1555 UBAUD = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
1556 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
1557 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
1558 ustcnt |= USTCNT_8_7;
1559 ustcnt |= USTCNT_TXEN;
1561 m68328_console_initted = 1;
1566 int m68328_console_setup(struct console *cp, char *arg)
1568 int i, n = CONSOLE_BAUD_RATE;
1574 n = simple_strtoul(arg,NULL,0);
1576 for (i = 0; i < BAUD_TABLE_SIZE; i++)
1577 if (baud_table[i] == n)
1579 if (i < BAUD_TABLE_SIZE) {
1580 m68328_console_baud = n;
1581 m68328_console_cbaud = 0;
1583 m68328_console_cbaud |= CBAUDEX;
1586 m68328_console_cbaud |= i;
1589 m68328_set_baud(); /* make sure baud rate changes */
1594 static struct tty_driver *m68328_console_device(struct console *c, int *index)
1597 return serial_driver;
1601 void m68328_console_write (struct console *co, const char *str,
1604 if (!m68328_console_initted)
1609 rs_put_char( *str++ );
1614 static struct console m68328_driver = {
1616 .write = m68328_console_write,
1617 .device = m68328_console_device,
1618 .setup = m68328_console_setup,
1619 .flags = CON_PRINTBUFFER,
1624 static int __init m68328_console_init(void)
1626 register_console(&m68328_driver);
1630 console_initcall(m68328_console_init);