1 /*
2 * Serial driver for the amiga builtin port.
3 *
4 * This code was created by taking serial.c version 4.30 from kernel
5 * release 2.3.22, replacing all hardware related stuff with the
6 * corresponding amiga hardware actions, and removing all irrelevant
7 * code. As a consequence, it uses many of the constants and names
8 * associated with the registers and bits of 16550 compatible UARTS -
9 * but only to keep track of status, etc in the state variables. It
10 * was done this was to make it easier to keep the code in line with
11 * (non hardware specific) changes to serial.c.
12 *
13 * The port is registered with the tty driver as minor device 64, and
14 * therefore other ports should should only use 65 upwards.
15 *
16 * Richard Lucock 28/12/99
17 *
18 * Copyright (C) 1991, 1992 Linus Torvalds
19 * Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997,
20 * 1998, 1999 Theodore Ts'o
21 *
22 */
23
24 /*
25 * Serial driver configuration section. Here are the various options:
26 *
27 * SERIAL_PARANOIA_CHECK
28 * Check the magic number for the async_structure where
29 * ever possible.
30 */
31
32 #include <linux/delay.h>
33
34 #undef SERIAL_PARANOIA_CHECK
35 #define SERIAL_DO_RESTART
36
37 /* Set of debugging defines */
38
39 #undef SERIAL_DEBUG_INTR
40 #undef SERIAL_DEBUG_OPEN
41 #undef SERIAL_DEBUG_FLOW
42 #undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
43
44 /* Sanity checks */
45
46 #if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
47 #define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
48 tty->name, (info->tport.flags), serial_driver->refcount,info->count,tty->count,s)
49 #else
50 #define DBG_CNT(s)
51 #endif
52
53 /*
54 * End of serial driver configuration section.
55 */
56
57 #include <linux/module.h>
58
59 #include <linux/types.h>
60 #include <linux/serial.h>
61 #include <linux/serial_reg.h>
62 static char *serial_version = "4.30";
63
64 #include <linux/errno.h>
65 #include <linux/signal.h>
66 #include <linux/sched.h>
67 #include <linux/kernel.h>
68 #include <linux/timer.h>
69 #include <linux/interrupt.h>
70 #include <linux/tty.h>
71 #include <linux/tty_flip.h>
72 #include <linux/circ_buf.h>
73 #include <linux/console.h>
74 #include <linux/major.h>
75 #include <linux/string.h>
76 #include <linux/fcntl.h>
77 #include <linux/ptrace.h>
78 #include <linux/ioport.h>
79 #include <linux/mm.h>
80 #include <linux/seq_file.h>
81 #include <linux/slab.h>
82 #include <linux/init.h>
83 #include <linux/bitops.h>
84 #include <linux/platform_device.h>
85
86 #include <asm/setup.h>
87
88
89 #include <asm/irq.h>
90
91 #include <asm/amigahw.h>
92 #include <asm/amigaints.h>
93
94 struct serial_state {
95 struct tty_port tport;
96 struct circ_buf xmit;
97 struct async_icount icount;
98
99 unsigned long port;
100 int baud_base;
101 int xmit_fifo_size;
102 int custom_divisor;
103 int read_status_mask;
104 int ignore_status_mask;
105 int timeout;
106 int quot;
107 int IER; /* Interrupt Enable Register */
108 int MCR; /* Modem control register */
109 int x_char; /* xon/xoff character */
110 };
111
112 #define custom amiga_custom
113 static char *serial_name = "Amiga-builtin serial driver";
114
115 static struct tty_driver *serial_driver;
116
117 /* number of characters left in xmit buffer before we ask for more */
118 #define WAKEUP_CHARS 256
119
120 static unsigned char current_ctl_bits;
121
122 static void change_speed(struct tty_struct *tty, struct serial_state *info,
123 struct ktermios *old);
124 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
125
126
127 static struct serial_state rs_table[1];
128
129 #define NR_PORTS ARRAY_SIZE(rs_table)
130
131 #include <asm/uaccess.h>
132
133 #define serial_isroot() (capable(CAP_SYS_ADMIN))
134
135
serial_paranoia_check(struct serial_state * info,char * name,const char * routine)136 static inline int serial_paranoia_check(struct serial_state *info,
137 char *name, const char *routine)
138 {
139 #ifdef SERIAL_PARANOIA_CHECK
140 static const char *badmagic =
141 "Warning: bad magic number for serial struct (%s) in %s\n";
142 static const char *badinfo =
143 "Warning: null async_struct for (%s) in %s\n";
144
145 if (!info) {
146 printk(badinfo, name, routine);
147 return 1;
148 }
149 if (info->magic != SERIAL_MAGIC) {
150 printk(badmagic, name, routine);
151 return 1;
152 }
153 #endif
154 return 0;
155 }
156
157 /* some serial hardware definitions */
158 #define SDR_OVRUN (1<<15)
159 #define SDR_RBF (1<<14)
160 #define SDR_TBE (1<<13)
161 #define SDR_TSRE (1<<12)
162
163 #define SERPER_PARENB (1<<15)
164
165 #define AC_SETCLR (1<<15)
166 #define AC_UARTBRK (1<<11)
167
168 #define SER_DTR (1<<7)
169 #define SER_RTS (1<<6)
170 #define SER_DCD (1<<5)
171 #define SER_CTS (1<<4)
172 #define SER_DSR (1<<3)
173
rtsdtr_ctrl(int bits)174 static __inline__ void rtsdtr_ctrl(int bits)
175 {
176 ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
177 }
178
179 /*
180 * ------------------------------------------------------------
181 * rs_stop() and rs_start()
182 *
183 * This routines are called before setting or resetting tty->stopped.
184 * They enable or disable transmitter interrupts, as necessary.
185 * ------------------------------------------------------------
186 */
rs_stop(struct tty_struct * tty)187 static void rs_stop(struct tty_struct *tty)
188 {
189 struct serial_state *info = tty->driver_data;
190 unsigned long flags;
191
192 if (serial_paranoia_check(info, tty->name, "rs_stop"))
193 return;
194
195 local_irq_save(flags);
196 if (info->IER & UART_IER_THRI) {
197 info->IER &= ~UART_IER_THRI;
198 /* disable Tx interrupt and remove any pending interrupts */
199 custom.intena = IF_TBE;
200 mb();
201 custom.intreq = IF_TBE;
202 mb();
203 }
204 local_irq_restore(flags);
205 }
206
rs_start(struct tty_struct * tty)207 static void rs_start(struct tty_struct *tty)
208 {
209 struct serial_state *info = tty->driver_data;
210 unsigned long flags;
211
212 if (serial_paranoia_check(info, tty->name, "rs_start"))
213 return;
214
215 local_irq_save(flags);
216 if (info->xmit.head != info->xmit.tail
217 && info->xmit.buf
218 && !(info->IER & UART_IER_THRI)) {
219 info->IER |= UART_IER_THRI;
220 custom.intena = IF_SETCLR | IF_TBE;
221 mb();
222 /* set a pending Tx Interrupt, transmitter should restart now */
223 custom.intreq = IF_SETCLR | IF_TBE;
224 mb();
225 }
226 local_irq_restore(flags);
227 }
228
229 /*
230 * ----------------------------------------------------------------------
231 *
232 * Here starts the interrupt handling routines. All of the following
233 * subroutines are declared as inline and are folded into
234 * rs_interrupt(). They were separated out for readability's sake.
235 *
236 * Note: rs_interrupt() is a "fast" interrupt, which means that it
237 * runs with interrupts turned off. People who may want to modify
238 * rs_interrupt() should try to keep the interrupt handler as fast as
239 * possible. After you are done making modifications, it is not a bad
240 * idea to do:
241 *
242 * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
243 *
244 * and look at the resulting assemble code in serial.s.
245 *
246 * - Ted Ts'o (tytso@mit.edu), 7-Mar-93
247 * -----------------------------------------------------------------------
248 */
249
receive_chars(struct serial_state * info)250 static void receive_chars(struct serial_state *info)
251 {
252 int status;
253 int serdatr;
254 unsigned char ch, flag;
255 struct async_icount *icount;
256 int oe = 0;
257
258 icount = &info->icount;
259
260 status = UART_LSR_DR; /* We obviously have a character! */
261 serdatr = custom.serdatr;
262 mb();
263 custom.intreq = IF_RBF;
264 mb();
265
266 if((serdatr & 0x1ff) == 0)
267 status |= UART_LSR_BI;
268 if(serdatr & SDR_OVRUN)
269 status |= UART_LSR_OE;
270
271 ch = serdatr & 0xff;
272 icount->rx++;
273
274 #ifdef SERIAL_DEBUG_INTR
275 printk("DR%02x:%02x...", ch, status);
276 #endif
277 flag = TTY_NORMAL;
278
279 /*
280 * We don't handle parity or frame errors - but I have left
281 * the code in, since I'm not sure that the errors can't be
282 * detected.
283 */
284
285 if (status & (UART_LSR_BI | UART_LSR_PE |
286 UART_LSR_FE | UART_LSR_OE)) {
287 /*
288 * For statistics only
289 */
290 if (status & UART_LSR_BI) {
291 status &= ~(UART_LSR_FE | UART_LSR_PE);
292 icount->brk++;
293 } else if (status & UART_LSR_PE)
294 icount->parity++;
295 else if (status & UART_LSR_FE)
296 icount->frame++;
297 if (status & UART_LSR_OE)
298 icount->overrun++;
299
300 /*
301 * Now check to see if character should be
302 * ignored, and mask off conditions which
303 * should be ignored.
304 */
305 if (status & info->ignore_status_mask)
306 goto out;
307
308 status &= info->read_status_mask;
309
310 if (status & (UART_LSR_BI)) {
311 #ifdef SERIAL_DEBUG_INTR
312 printk("handling break....");
313 #endif
314 flag = TTY_BREAK;
315 if (info->tport.flags & ASYNC_SAK)
316 do_SAK(info->tport.tty);
317 } else if (status & UART_LSR_PE)
318 flag = TTY_PARITY;
319 else if (status & UART_LSR_FE)
320 flag = TTY_FRAME;
321 if (status & UART_LSR_OE) {
322 /*
323 * Overrun is special, since it's
324 * reported immediately, and doesn't
325 * affect the current character
326 */
327 oe = 1;
328 }
329 }
330 tty_insert_flip_char(&info->tport, ch, flag);
331 if (oe == 1)
332 tty_insert_flip_char(&info->tport, 0, TTY_OVERRUN);
333 tty_flip_buffer_push(&info->tport);
334 out:
335 return;
336 }
337
transmit_chars(struct serial_state * info)338 static void transmit_chars(struct serial_state *info)
339 {
340 custom.intreq = IF_TBE;
341 mb();
342 if (info->x_char) {
343 custom.serdat = info->x_char | 0x100;
344 mb();
345 info->icount.tx++;
346 info->x_char = 0;
347 return;
348 }
349 if (info->xmit.head == info->xmit.tail
350 || info->tport.tty->stopped
351 || info->tport.tty->hw_stopped) {
352 info->IER &= ~UART_IER_THRI;
353 custom.intena = IF_TBE;
354 mb();
355 return;
356 }
357
358 custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
359 mb();
360 info->xmit.tail = info->xmit.tail & (SERIAL_XMIT_SIZE-1);
361 info->icount.tx++;
362
363 if (CIRC_CNT(info->xmit.head,
364 info->xmit.tail,
365 SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
366 tty_wakeup(info->tport.tty);
367
368 #ifdef SERIAL_DEBUG_INTR
369 printk("THRE...");
370 #endif
371 if (info->xmit.head == info->xmit.tail) {
372 custom.intena = IF_TBE;
373 mb();
374 info->IER &= ~UART_IER_THRI;
375 }
376 }
377
check_modem_status(struct serial_state * info)378 static void check_modem_status(struct serial_state *info)
379 {
380 struct tty_port *port = &info->tport;
381 unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
382 unsigned char dstatus;
383 struct async_icount *icount;
384
385 /* Determine bits that have changed */
386 dstatus = status ^ current_ctl_bits;
387 current_ctl_bits = status;
388
389 if (dstatus) {
390 icount = &info->icount;
391 /* update input line counters */
392 if (dstatus & SER_DSR)
393 icount->dsr++;
394 if (dstatus & SER_DCD) {
395 icount->dcd++;
396 }
397 if (dstatus & SER_CTS)
398 icount->cts++;
399 wake_up_interruptible(&port->delta_msr_wait);
400 }
401
402 if ((port->flags & ASYNC_CHECK_CD) && (dstatus & SER_DCD)) {
403 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
404 printk("ttyS%d CD now %s...", info->line,
405 (!(status & SER_DCD)) ? "on" : "off");
406 #endif
407 if (!(status & SER_DCD))
408 wake_up_interruptible(&port->open_wait);
409 else {
410 #ifdef SERIAL_DEBUG_OPEN
411 printk("doing serial hangup...");
412 #endif
413 if (port->tty)
414 tty_hangup(port->tty);
415 }
416 }
417 if (tty_port_cts_enabled(port)) {
418 if (port->tty->hw_stopped) {
419 if (!(status & SER_CTS)) {
420 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
421 printk("CTS tx start...");
422 #endif
423 port->tty->hw_stopped = 0;
424 info->IER |= UART_IER_THRI;
425 custom.intena = IF_SETCLR | IF_TBE;
426 mb();
427 /* set a pending Tx Interrupt, transmitter should restart now */
428 custom.intreq = IF_SETCLR | IF_TBE;
429 mb();
430 tty_wakeup(port->tty);
431 return;
432 }
433 } else {
434 if ((status & SER_CTS)) {
435 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
436 printk("CTS tx stop...");
437 #endif
438 port->tty->hw_stopped = 1;
439 info->IER &= ~UART_IER_THRI;
440 /* disable Tx interrupt and remove any pending interrupts */
441 custom.intena = IF_TBE;
442 mb();
443 custom.intreq = IF_TBE;
444 mb();
445 }
446 }
447 }
448 }
449
ser_vbl_int(int irq,void * data)450 static irqreturn_t ser_vbl_int( int irq, void *data)
451 {
452 /* vbl is just a periodic interrupt we tie into to update modem status */
453 struct serial_state *info = data;
454 /*
455 * TBD - is it better to unregister from this interrupt or to
456 * ignore it if MSI is clear ?
457 */
458 if(info->IER & UART_IER_MSI)
459 check_modem_status(info);
460 return IRQ_HANDLED;
461 }
462
ser_rx_int(int irq,void * dev_id)463 static irqreturn_t ser_rx_int(int irq, void *dev_id)
464 {
465 struct serial_state *info = dev_id;
466
467 #ifdef SERIAL_DEBUG_INTR
468 printk("ser_rx_int...");
469 #endif
470
471 if (!info->tport.tty)
472 return IRQ_NONE;
473
474 receive_chars(info);
475 #ifdef SERIAL_DEBUG_INTR
476 printk("end.\n");
477 #endif
478 return IRQ_HANDLED;
479 }
480
ser_tx_int(int irq,void * dev_id)481 static irqreturn_t ser_tx_int(int irq, void *dev_id)
482 {
483 struct serial_state *info = dev_id;
484
485 if (custom.serdatr & SDR_TBE) {
486 #ifdef SERIAL_DEBUG_INTR
487 printk("ser_tx_int...");
488 #endif
489
490 if (!info->tport.tty)
491 return IRQ_NONE;
492
493 transmit_chars(info);
494 #ifdef SERIAL_DEBUG_INTR
495 printk("end.\n");
496 #endif
497 }
498 return IRQ_HANDLED;
499 }
500
501 /*
502 * -------------------------------------------------------------------
503 * Here ends the serial interrupt routines.
504 * -------------------------------------------------------------------
505 */
506
507 /*
508 * ---------------------------------------------------------------
509 * Low level utility subroutines for the serial driver: routines to
510 * figure out the appropriate timeout for an interrupt chain, routines
511 * to initialize and startup a serial port, and routines to shutdown a
512 * serial port. Useful stuff like that.
513 * ---------------------------------------------------------------
514 */
515
startup(struct tty_struct * tty,struct serial_state * info)516 static int startup(struct tty_struct *tty, struct serial_state *info)
517 {
518 struct tty_port *port = &info->tport;
519 unsigned long flags;
520 int retval=0;
521 unsigned long page;
522
523 page = get_zeroed_page(GFP_KERNEL);
524 if (!page)
525 return -ENOMEM;
526
527 local_irq_save(flags);
528
529 if (port->flags & ASYNC_INITIALIZED) {
530 free_page(page);
531 goto errout;
532 }
533
534 if (info->xmit.buf)
535 free_page(page);
536 else
537 info->xmit.buf = (unsigned char *) page;
538
539 #ifdef SERIAL_DEBUG_OPEN
540 printk("starting up ttys%d ...", info->line);
541 #endif
542
543 /* Clear anything in the input buffer */
544
545 custom.intreq = IF_RBF;
546 mb();
547
548 retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
549 if (retval) {
550 if (serial_isroot()) {
551 set_bit(TTY_IO_ERROR, &tty->flags);
552 retval = 0;
553 }
554 goto errout;
555 }
556
557 /* enable both Rx and Tx interrupts */
558 custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
559 mb();
560 info->IER = UART_IER_MSI;
561
562 /* remember current state of the DCD and CTS bits */
563 current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
564
565 info->MCR = 0;
566 if (C_BAUD(tty))
567 info->MCR = SER_DTR | SER_RTS;
568 rtsdtr_ctrl(info->MCR);
569
570 clear_bit(TTY_IO_ERROR, &tty->flags);
571 info->xmit.head = info->xmit.tail = 0;
572
573 /*
574 * Set up the tty->alt_speed kludge
575 */
576 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
577 tty->alt_speed = 57600;
578 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
579 tty->alt_speed = 115200;
580 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
581 tty->alt_speed = 230400;
582 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
583 tty->alt_speed = 460800;
584
585 /*
586 * and set the speed of the serial port
587 */
588 change_speed(tty, info, NULL);
589
590 port->flags |= ASYNC_INITIALIZED;
591 local_irq_restore(flags);
592 return 0;
593
594 errout:
595 local_irq_restore(flags);
596 return retval;
597 }
598
599 /*
600 * This routine will shutdown a serial port; interrupts are disabled, and
601 * DTR is dropped if the hangup on close termio flag is on.
602 */
shutdown(struct tty_struct * tty,struct serial_state * info)603 static void shutdown(struct tty_struct *tty, struct serial_state *info)
604 {
605 unsigned long flags;
606 struct serial_state *state;
607
608 if (!(info->tport.flags & ASYNC_INITIALIZED))
609 return;
610
611 state = info;
612
613 #ifdef SERIAL_DEBUG_OPEN
614 printk("Shutting down serial port %d ....\n", info->line);
615 #endif
616
617 local_irq_save(flags); /* Disable interrupts */
618
619 /*
620 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
621 * here so the queue might never be waken up
622 */
623 wake_up_interruptible(&info->tport.delta_msr_wait);
624
625 /*
626 * Free the IRQ, if necessary
627 */
628 free_irq(IRQ_AMIGA_VERTB, info);
629
630 if (info->xmit.buf) {
631 free_page((unsigned long) info->xmit.buf);
632 info->xmit.buf = NULL;
633 }
634
635 info->IER = 0;
636 custom.intena = IF_RBF | IF_TBE;
637 mb();
638
639 /* disable break condition */
640 custom.adkcon = AC_UARTBRK;
641 mb();
642
643 if (tty->termios.c_cflag & HUPCL)
644 info->MCR &= ~(SER_DTR|SER_RTS);
645 rtsdtr_ctrl(info->MCR);
646
647 set_bit(TTY_IO_ERROR, &tty->flags);
648
649 info->tport.flags &= ~ASYNC_INITIALIZED;
650 local_irq_restore(flags);
651 }
652
653
654 /*
655 * This routine is called to set the UART divisor registers to match
656 * the specified baud rate for a serial port.
657 */
change_speed(struct tty_struct * tty,struct serial_state * info,struct ktermios * old_termios)658 static void change_speed(struct tty_struct *tty, struct serial_state *info,
659 struct ktermios *old_termios)
660 {
661 struct tty_port *port = &info->tport;
662 int quot = 0, baud_base, baud;
663 unsigned cflag, cval = 0;
664 int bits;
665 unsigned long flags;
666
667 cflag = tty->termios.c_cflag;
668
669 /* Byte size is always 8 bits plus parity bit if requested */
670
671 cval = 3; bits = 10;
672 if (cflag & CSTOPB) {
673 cval |= 0x04;
674 bits++;
675 }
676 if (cflag & PARENB) {
677 cval |= UART_LCR_PARITY;
678 bits++;
679 }
680 if (!(cflag & PARODD))
681 cval |= UART_LCR_EPAR;
682 #ifdef CMSPAR
683 if (cflag & CMSPAR)
684 cval |= UART_LCR_SPAR;
685 #endif
686
687 /* Determine divisor based on baud rate */
688 baud = tty_get_baud_rate(tty);
689 if (!baud)
690 baud = 9600; /* B0 transition handled in rs_set_termios */
691 baud_base = info->baud_base;
692 if (baud == 38400 && (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
693 quot = info->custom_divisor;
694 else {
695 if (baud == 134)
696 /* Special case since 134 is really 134.5 */
697 quot = (2*baud_base / 269);
698 else if (baud)
699 quot = baud_base / baud;
700 }
701 /* If the quotient is zero refuse the change */
702 if (!quot && old_termios) {
703 /* FIXME: Will need updating for new tty in the end */
704 tty->termios.c_cflag &= ~CBAUD;
705 tty->termios.c_cflag |= (old_termios->c_cflag & CBAUD);
706 baud = tty_get_baud_rate(tty);
707 if (!baud)
708 baud = 9600;
709 if (baud == 38400 &&
710 (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
711 quot = info->custom_divisor;
712 else {
713 if (baud == 134)
714 /* Special case since 134 is really 134.5 */
715 quot = (2*baud_base / 269);
716 else if (baud)
717 quot = baud_base / baud;
718 }
719 }
720 /* As a last resort, if the quotient is zero, default to 9600 bps */
721 if (!quot)
722 quot = baud_base / 9600;
723 info->quot = quot;
724 info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
725 info->timeout += HZ/50; /* Add .02 seconds of slop */
726
727 /* CTS flow control flag and modem status interrupts */
728 info->IER &= ~UART_IER_MSI;
729 if (port->flags & ASYNC_HARDPPS_CD)
730 info->IER |= UART_IER_MSI;
731 if (cflag & CRTSCTS) {
732 port->flags |= ASYNC_CTS_FLOW;
733 info->IER |= UART_IER_MSI;
734 } else
735 port->flags &= ~ASYNC_CTS_FLOW;
736 if (cflag & CLOCAL)
737 port->flags &= ~ASYNC_CHECK_CD;
738 else {
739 port->flags |= ASYNC_CHECK_CD;
740 info->IER |= UART_IER_MSI;
741 }
742 /* TBD:
743 * Does clearing IER_MSI imply that we should disable the VBL interrupt ?
744 */
745
746 /*
747 * Set up parity check flag
748 */
749
750 info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
751 if (I_INPCK(tty))
752 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
753 if (I_BRKINT(tty) || I_PARMRK(tty))
754 info->read_status_mask |= UART_LSR_BI;
755
756 /*
757 * Characters to ignore
758 */
759 info->ignore_status_mask = 0;
760 if (I_IGNPAR(tty))
761 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
762 if (I_IGNBRK(tty)) {
763 info->ignore_status_mask |= UART_LSR_BI;
764 /*
765 * If we're ignore parity and break indicators, ignore
766 * overruns too. (For real raw support).
767 */
768 if (I_IGNPAR(tty))
769 info->ignore_status_mask |= UART_LSR_OE;
770 }
771 /*
772 * !!! ignore all characters if CREAD is not set
773 */
774 if ((cflag & CREAD) == 0)
775 info->ignore_status_mask |= UART_LSR_DR;
776 local_irq_save(flags);
777
778 {
779 short serper;
780
781 /* Set up the baud rate */
782 serper = quot - 1;
783
784 /* Enable or disable parity bit */
785
786 if(cval & UART_LCR_PARITY)
787 serper |= (SERPER_PARENB);
788
789 custom.serper = serper;
790 mb();
791 }
792
793 local_irq_restore(flags);
794 }
795
rs_put_char(struct tty_struct * tty,unsigned char ch)796 static int rs_put_char(struct tty_struct *tty, unsigned char ch)
797 {
798 struct serial_state *info;
799 unsigned long flags;
800
801 info = tty->driver_data;
802
803 if (serial_paranoia_check(info, tty->name, "rs_put_char"))
804 return 0;
805
806 if (!info->xmit.buf)
807 return 0;
808
809 local_irq_save(flags);
810 if (CIRC_SPACE(info->xmit.head,
811 info->xmit.tail,
812 SERIAL_XMIT_SIZE) == 0) {
813 local_irq_restore(flags);
814 return 0;
815 }
816
817 info->xmit.buf[info->xmit.head++] = ch;
818 info->xmit.head &= SERIAL_XMIT_SIZE-1;
819 local_irq_restore(flags);
820 return 1;
821 }
822
rs_flush_chars(struct tty_struct * tty)823 static void rs_flush_chars(struct tty_struct *tty)
824 {
825 struct serial_state *info = tty->driver_data;
826 unsigned long flags;
827
828 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
829 return;
830
831 if (info->xmit.head == info->xmit.tail
832 || tty->stopped
833 || tty->hw_stopped
834 || !info->xmit.buf)
835 return;
836
837 local_irq_save(flags);
838 info->IER |= UART_IER_THRI;
839 custom.intena = IF_SETCLR | IF_TBE;
840 mb();
841 /* set a pending Tx Interrupt, transmitter should restart now */
842 custom.intreq = IF_SETCLR | IF_TBE;
843 mb();
844 local_irq_restore(flags);
845 }
846
rs_write(struct tty_struct * tty,const unsigned char * buf,int count)847 static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
848 {
849 int c, ret = 0;
850 struct serial_state *info = tty->driver_data;
851 unsigned long flags;
852
853 if (serial_paranoia_check(info, tty->name, "rs_write"))
854 return 0;
855
856 if (!info->xmit.buf)
857 return 0;
858
859 local_irq_save(flags);
860 while (1) {
861 c = CIRC_SPACE_TO_END(info->xmit.head,
862 info->xmit.tail,
863 SERIAL_XMIT_SIZE);
864 if (count < c)
865 c = count;
866 if (c <= 0) {
867 break;
868 }
869 memcpy(info->xmit.buf + info->xmit.head, buf, c);
870 info->xmit.head = ((info->xmit.head + c) &
871 (SERIAL_XMIT_SIZE-1));
872 buf += c;
873 count -= c;
874 ret += c;
875 }
876 local_irq_restore(flags);
877
878 if (info->xmit.head != info->xmit.tail
879 && !tty->stopped
880 && !tty->hw_stopped
881 && !(info->IER & UART_IER_THRI)) {
882 info->IER |= UART_IER_THRI;
883 local_irq_disable();
884 custom.intena = IF_SETCLR | IF_TBE;
885 mb();
886 /* set a pending Tx Interrupt, transmitter should restart now */
887 custom.intreq = IF_SETCLR | IF_TBE;
888 mb();
889 local_irq_restore(flags);
890 }
891 return ret;
892 }
893
rs_write_room(struct tty_struct * tty)894 static int rs_write_room(struct tty_struct *tty)
895 {
896 struct serial_state *info = tty->driver_data;
897
898 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
899 return 0;
900 return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
901 }
902
rs_chars_in_buffer(struct tty_struct * tty)903 static int rs_chars_in_buffer(struct tty_struct *tty)
904 {
905 struct serial_state *info = tty->driver_data;
906
907 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
908 return 0;
909 return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
910 }
911
rs_flush_buffer(struct tty_struct * tty)912 static void rs_flush_buffer(struct tty_struct *tty)
913 {
914 struct serial_state *info = tty->driver_data;
915 unsigned long flags;
916
917 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
918 return;
919 local_irq_save(flags);
920 info->xmit.head = info->xmit.tail = 0;
921 local_irq_restore(flags);
922 tty_wakeup(tty);
923 }
924
925 /*
926 * This function is used to send a high-priority XON/XOFF character to
927 * the device
928 */
rs_send_xchar(struct tty_struct * tty,char ch)929 static void rs_send_xchar(struct tty_struct *tty, char ch)
930 {
931 struct serial_state *info = tty->driver_data;
932 unsigned long flags;
933
934 if (serial_paranoia_check(info, tty->name, "rs_send_char"))
935 return;
936
937 info->x_char = ch;
938 if (ch) {
939 /* Make sure transmit interrupts are on */
940
941 /* Check this ! */
942 local_irq_save(flags);
943 if(!(custom.intenar & IF_TBE)) {
944 custom.intena = IF_SETCLR | IF_TBE;
945 mb();
946 /* set a pending Tx Interrupt, transmitter should restart now */
947 custom.intreq = IF_SETCLR | IF_TBE;
948 mb();
949 }
950 local_irq_restore(flags);
951
952 info->IER |= UART_IER_THRI;
953 }
954 }
955
956 /*
957 * ------------------------------------------------------------
958 * rs_throttle()
959 *
960 * This routine is called by the upper-layer tty layer to signal that
961 * incoming characters should be throttled.
962 * ------------------------------------------------------------
963 */
rs_throttle(struct tty_struct * tty)964 static void rs_throttle(struct tty_struct * tty)
965 {
966 struct serial_state *info = tty->driver_data;
967 unsigned long flags;
968 #ifdef SERIAL_DEBUG_THROTTLE
969 char buf[64];
970
971 printk("throttle %s: %d....\n", tty_name(tty, buf),
972 tty->ldisc.chars_in_buffer(tty));
973 #endif
974
975 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
976 return;
977
978 if (I_IXOFF(tty))
979 rs_send_xchar(tty, STOP_CHAR(tty));
980
981 if (tty->termios.c_cflag & CRTSCTS)
982 info->MCR &= ~SER_RTS;
983
984 local_irq_save(flags);
985 rtsdtr_ctrl(info->MCR);
986 local_irq_restore(flags);
987 }
988
rs_unthrottle(struct tty_struct * tty)989 static void rs_unthrottle(struct tty_struct * tty)
990 {
991 struct serial_state *info = tty->driver_data;
992 unsigned long flags;
993 #ifdef SERIAL_DEBUG_THROTTLE
994 char buf[64];
995
996 printk("unthrottle %s: %d....\n", tty_name(tty, buf),
997 tty->ldisc.chars_in_buffer(tty));
998 #endif
999
1000 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1001 return;
1002
1003 if (I_IXOFF(tty)) {
1004 if (info->x_char)
1005 info->x_char = 0;
1006 else
1007 rs_send_xchar(tty, START_CHAR(tty));
1008 }
1009 if (tty->termios.c_cflag & CRTSCTS)
1010 info->MCR |= SER_RTS;
1011 local_irq_save(flags);
1012 rtsdtr_ctrl(info->MCR);
1013 local_irq_restore(flags);
1014 }
1015
1016 /*
1017 * ------------------------------------------------------------
1018 * rs_ioctl() and friends
1019 * ------------------------------------------------------------
1020 */
1021
get_serial_info(struct tty_struct * tty,struct serial_state * state,struct serial_struct __user * retinfo)1022 static int get_serial_info(struct tty_struct *tty, struct serial_state *state,
1023 struct serial_struct __user * retinfo)
1024 {
1025 struct serial_struct tmp;
1026
1027 if (!retinfo)
1028 return -EFAULT;
1029 memset(&tmp, 0, sizeof(tmp));
1030 tty_lock(tty);
1031 tmp.line = tty->index;
1032 tmp.port = state->port;
1033 tmp.flags = state->tport.flags;
1034 tmp.xmit_fifo_size = state->xmit_fifo_size;
1035 tmp.baud_base = state->baud_base;
1036 tmp.close_delay = state->tport.close_delay;
1037 tmp.closing_wait = state->tport.closing_wait;
1038 tmp.custom_divisor = state->custom_divisor;
1039 tty_unlock(tty);
1040 if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1041 return -EFAULT;
1042 return 0;
1043 }
1044
set_serial_info(struct tty_struct * tty,struct serial_state * state,struct serial_struct __user * new_info)1045 static int set_serial_info(struct tty_struct *tty, struct serial_state *state,
1046 struct serial_struct __user * new_info)
1047 {
1048 struct tty_port *port = &state->tport;
1049 struct serial_struct new_serial;
1050 bool change_spd;
1051 int retval = 0;
1052
1053 if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1054 return -EFAULT;
1055
1056 tty_lock(tty);
1057 change_spd = ((new_serial.flags ^ port->flags) & ASYNC_SPD_MASK) ||
1058 new_serial.custom_divisor != state->custom_divisor;
1059 if (new_serial.irq || new_serial.port != state->port ||
1060 new_serial.xmit_fifo_size != state->xmit_fifo_size) {
1061 tty_unlock(tty);
1062 return -EINVAL;
1063 }
1064
1065 if (!serial_isroot()) {
1066 if ((new_serial.baud_base != state->baud_base) ||
1067 (new_serial.close_delay != port->close_delay) ||
1068 (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
1069 ((new_serial.flags & ~ASYNC_USR_MASK) !=
1070 (port->flags & ~ASYNC_USR_MASK))) {
1071 tty_unlock(tty);
1072 return -EPERM;
1073 }
1074 port->flags = ((port->flags & ~ASYNC_USR_MASK) |
1075 (new_serial.flags & ASYNC_USR_MASK));
1076 state->custom_divisor = new_serial.custom_divisor;
1077 goto check_and_exit;
1078 }
1079
1080 if (new_serial.baud_base < 9600) {
1081 tty_unlock(tty);
1082 return -EINVAL;
1083 }
1084
1085 /*
1086 * OK, past this point, all the error checking has been done.
1087 * At this point, we start making changes.....
1088 */
1089
1090 state->baud_base = new_serial.baud_base;
1091 port->flags = ((port->flags & ~ASYNC_FLAGS) |
1092 (new_serial.flags & ASYNC_FLAGS));
1093 state->custom_divisor = new_serial.custom_divisor;
1094 port->close_delay = new_serial.close_delay * HZ/100;
1095 port->closing_wait = new_serial.closing_wait * HZ/100;
1096 port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1097
1098 check_and_exit:
1099 if (port->flags & ASYNC_INITIALIZED) {
1100 if (change_spd) {
1101 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1102 tty->alt_speed = 57600;
1103 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1104 tty->alt_speed = 115200;
1105 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1106 tty->alt_speed = 230400;
1107 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1108 tty->alt_speed = 460800;
1109 change_speed(tty, state, NULL);
1110 }
1111 } else
1112 retval = startup(tty, state);
1113 tty_unlock(tty);
1114 return retval;
1115 }
1116
1117
1118 /*
1119 * get_lsr_info - get line status register info
1120 *
1121 * Purpose: Let user call ioctl() to get info when the UART physically
1122 * is emptied. On bus types like RS485, the transmitter must
1123 * release the bus after transmitting. This must be done when
1124 * the transmit shift register is empty, not be done when the
1125 * transmit holding register is empty. This functionality
1126 * allows an RS485 driver to be written in user space.
1127 */
get_lsr_info(struct serial_state * info,unsigned int __user * value)1128 static int get_lsr_info(struct serial_state *info, unsigned int __user *value)
1129 {
1130 unsigned char status;
1131 unsigned int result;
1132 unsigned long flags;
1133
1134 local_irq_save(flags);
1135 status = custom.serdatr;
1136 mb();
1137 local_irq_restore(flags);
1138 result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
1139 if (copy_to_user(value, &result, sizeof(int)))
1140 return -EFAULT;
1141 return 0;
1142 }
1143
1144
rs_tiocmget(struct tty_struct * tty)1145 static int rs_tiocmget(struct tty_struct *tty)
1146 {
1147 struct serial_state *info = tty->driver_data;
1148 unsigned char control, status;
1149 unsigned long flags;
1150
1151 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1152 return -ENODEV;
1153 if (tty->flags & (1 << TTY_IO_ERROR))
1154 return -EIO;
1155
1156 control = info->MCR;
1157 local_irq_save(flags);
1158 status = ciab.pra;
1159 local_irq_restore(flags);
1160 return ((control & SER_RTS) ? TIOCM_RTS : 0)
1161 | ((control & SER_DTR) ? TIOCM_DTR : 0)
1162 | (!(status & SER_DCD) ? TIOCM_CAR : 0)
1163 | (!(status & SER_DSR) ? TIOCM_DSR : 0)
1164 | (!(status & SER_CTS) ? TIOCM_CTS : 0);
1165 }
1166
rs_tiocmset(struct tty_struct * tty,unsigned int set,unsigned int clear)1167 static int rs_tiocmset(struct tty_struct *tty, unsigned int set,
1168 unsigned int clear)
1169 {
1170 struct serial_state *info = tty->driver_data;
1171 unsigned long flags;
1172
1173 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1174 return -ENODEV;
1175 if (tty->flags & (1 << TTY_IO_ERROR))
1176 return -EIO;
1177
1178 local_irq_save(flags);
1179 if (set & TIOCM_RTS)
1180 info->MCR |= SER_RTS;
1181 if (set & TIOCM_DTR)
1182 info->MCR |= SER_DTR;
1183 if (clear & TIOCM_RTS)
1184 info->MCR &= ~SER_RTS;
1185 if (clear & TIOCM_DTR)
1186 info->MCR &= ~SER_DTR;
1187 rtsdtr_ctrl(info->MCR);
1188 local_irq_restore(flags);
1189 return 0;
1190 }
1191
1192 /*
1193 * rs_break() --- routine which turns the break handling on or off
1194 */
rs_break(struct tty_struct * tty,int break_state)1195 static int rs_break(struct tty_struct *tty, int break_state)
1196 {
1197 struct serial_state *info = tty->driver_data;
1198 unsigned long flags;
1199
1200 if (serial_paranoia_check(info, tty->name, "rs_break"))
1201 return -EINVAL;
1202
1203 local_irq_save(flags);
1204 if (break_state == -1)
1205 custom.adkcon = AC_SETCLR | AC_UARTBRK;
1206 else
1207 custom.adkcon = AC_UARTBRK;
1208 mb();
1209 local_irq_restore(flags);
1210 return 0;
1211 }
1212
1213 /*
1214 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1215 * Return: write counters to the user passed counter struct
1216 * NB: both 1->0 and 0->1 transitions are counted except for
1217 * RI where only 0->1 is counted.
1218 */
rs_get_icount(struct tty_struct * tty,struct serial_icounter_struct * icount)1219 static int rs_get_icount(struct tty_struct *tty,
1220 struct serial_icounter_struct *icount)
1221 {
1222 struct serial_state *info = tty->driver_data;
1223 struct async_icount cnow;
1224 unsigned long flags;
1225
1226 local_irq_save(flags);
1227 cnow = info->icount;
1228 local_irq_restore(flags);
1229 icount->cts = cnow.cts;
1230 icount->dsr = cnow.dsr;
1231 icount->rng = cnow.rng;
1232 icount->dcd = cnow.dcd;
1233 icount->rx = cnow.rx;
1234 icount->tx = cnow.tx;
1235 icount->frame = cnow.frame;
1236 icount->overrun = cnow.overrun;
1237 icount->parity = cnow.parity;
1238 icount->brk = cnow.brk;
1239 icount->buf_overrun = cnow.buf_overrun;
1240
1241 return 0;
1242 }
1243
rs_ioctl(struct tty_struct * tty,unsigned int cmd,unsigned long arg)1244 static int rs_ioctl(struct tty_struct *tty,
1245 unsigned int cmd, unsigned long arg)
1246 {
1247 struct serial_state *info = tty->driver_data;
1248 struct async_icount cprev, cnow; /* kernel counter temps */
1249 void __user *argp = (void __user *)arg;
1250 unsigned long flags;
1251
1252 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1253 return -ENODEV;
1254
1255 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1256 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
1257 (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1258 if (tty->flags & (1 << TTY_IO_ERROR))
1259 return -EIO;
1260 }
1261
1262 switch (cmd) {
1263 case TIOCGSERIAL:
1264 return get_serial_info(tty, info, argp);
1265 case TIOCSSERIAL:
1266 return set_serial_info(tty, info, argp);
1267 case TIOCSERCONFIG:
1268 return 0;
1269
1270 case TIOCSERGETLSR: /* Get line status register */
1271 return get_lsr_info(info, argp);
1272
1273 case TIOCSERGSTRUCT:
1274 if (copy_to_user(argp,
1275 info, sizeof(struct serial_state)))
1276 return -EFAULT;
1277 return 0;
1278
1279 /*
1280 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1281 * - mask passed in arg for lines of interest
1282 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1283 * Caller should use TIOCGICOUNT to see which one it was
1284 */
1285 case TIOCMIWAIT:
1286 local_irq_save(flags);
1287 /* note the counters on entry */
1288 cprev = info->icount;
1289 local_irq_restore(flags);
1290 while (1) {
1291 interruptible_sleep_on(&info->tport.delta_msr_wait);
1292 /* see if a signal did it */
1293 if (signal_pending(current))
1294 return -ERESTARTSYS;
1295 local_irq_save(flags);
1296 cnow = info->icount; /* atomic copy */
1297 local_irq_restore(flags);
1298 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
1299 cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1300 return -EIO; /* no change => error */
1301 if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1302 ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1303 ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
1304 ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1305 return 0;
1306 }
1307 cprev = cnow;
1308 }
1309 /* NOTREACHED */
1310
1311 case TIOCSERGWILD:
1312 case TIOCSERSWILD:
1313 /* "setserial -W" is called in Debian boot */
1314 printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
1315 return 0;
1316
1317 default:
1318 return -ENOIOCTLCMD;
1319 }
1320 return 0;
1321 }
1322
rs_set_termios(struct tty_struct * tty,struct ktermios * old_termios)1323 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
1324 {
1325 struct serial_state *info = tty->driver_data;
1326 unsigned long flags;
1327 unsigned int cflag = tty->termios.c_cflag;
1328
1329 change_speed(tty, info, old_termios);
1330
1331 /* Handle transition to B0 status */
1332 if ((old_termios->c_cflag & CBAUD) &&
1333 !(cflag & CBAUD)) {
1334 info->MCR &= ~(SER_DTR|SER_RTS);
1335 local_irq_save(flags);
1336 rtsdtr_ctrl(info->MCR);
1337 local_irq_restore(flags);
1338 }
1339
1340 /* Handle transition away from B0 status */
1341 if (!(old_termios->c_cflag & CBAUD) &&
1342 (cflag & CBAUD)) {
1343 info->MCR |= SER_DTR;
1344 if (!(tty->termios.c_cflag & CRTSCTS) ||
1345 !test_bit(TTY_THROTTLED, &tty->flags)) {
1346 info->MCR |= SER_RTS;
1347 }
1348 local_irq_save(flags);
1349 rtsdtr_ctrl(info->MCR);
1350 local_irq_restore(flags);
1351 }
1352
1353 /* Handle turning off CRTSCTS */
1354 if ((old_termios->c_cflag & CRTSCTS) &&
1355 !(tty->termios.c_cflag & CRTSCTS)) {
1356 tty->hw_stopped = 0;
1357 rs_start(tty);
1358 }
1359
1360 #if 0
1361 /*
1362 * No need to wake up processes in open wait, since they
1363 * sample the CLOCAL flag once, and don't recheck it.
1364 * XXX It's not clear whether the current behavior is correct
1365 * or not. Hence, this may change.....
1366 */
1367 if (!(old_termios->c_cflag & CLOCAL) &&
1368 (tty->termios.c_cflag & CLOCAL))
1369 wake_up_interruptible(&info->open_wait);
1370 #endif
1371 }
1372
1373 /*
1374 * ------------------------------------------------------------
1375 * rs_close()
1376 *
1377 * This routine is called when the serial port gets closed. First, we
1378 * wait for the last remaining data to be sent. Then, we unlink its
1379 * async structure from the interrupt chain if necessary, and we free
1380 * that IRQ if nothing is left in the chain.
1381 * ------------------------------------------------------------
1382 */
rs_close(struct tty_struct * tty,struct file * filp)1383 static void rs_close(struct tty_struct *tty, struct file * filp)
1384 {
1385 struct serial_state *state = tty->driver_data;
1386 struct tty_port *port = &state->tport;
1387
1388 if (serial_paranoia_check(state, tty->name, "rs_close"))
1389 return;
1390
1391 if (tty_port_close_start(port, tty, filp) == 0)
1392 return;
1393
1394 /*
1395 * At this point we stop accepting input. To do this, we
1396 * disable the receive line status interrupts, and tell the
1397 * interrupt driver to stop checking the data ready bit in the
1398 * line status register.
1399 */
1400 state->read_status_mask &= ~UART_LSR_DR;
1401 if (port->flags & ASYNC_INITIALIZED) {
1402 /* disable receive interrupts */
1403 custom.intena = IF_RBF;
1404 mb();
1405 /* clear any pending receive interrupt */
1406 custom.intreq = IF_RBF;
1407 mb();
1408
1409 /*
1410 * Before we drop DTR, make sure the UART transmitter
1411 * has completely drained; this is especially
1412 * important if there is a transmit FIFO!
1413 */
1414 rs_wait_until_sent(tty, state->timeout);
1415 }
1416 shutdown(tty, state);
1417 rs_flush_buffer(tty);
1418
1419 tty_ldisc_flush(tty);
1420 port->tty = NULL;
1421
1422 tty_port_close_end(port, tty);
1423 }
1424
1425 /*
1426 * rs_wait_until_sent() --- wait until the transmitter is empty
1427 */
rs_wait_until_sent(struct tty_struct * tty,int timeout)1428 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1429 {
1430 struct serial_state *info = tty->driver_data;
1431 unsigned long orig_jiffies, char_time;
1432 int lsr;
1433
1434 if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
1435 return;
1436
1437 if (info->xmit_fifo_size == 0)
1438 return; /* Just in case.... */
1439
1440 orig_jiffies = jiffies;
1441
1442 /*
1443 * Set the check interval to be 1/5 of the estimated time to
1444 * send a single character, and make it at least 1. The check
1445 * interval should also be less than the timeout.
1446 *
1447 * Note: we have to use pretty tight timings here to satisfy
1448 * the NIST-PCTS.
1449 */
1450 char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1451 char_time = char_time / 5;
1452 if (char_time == 0)
1453 char_time = 1;
1454 if (timeout)
1455 char_time = min_t(unsigned long, char_time, timeout);
1456 /*
1457 * If the transmitter hasn't cleared in twice the approximate
1458 * amount of time to send the entire FIFO, it probably won't
1459 * ever clear. This assumes the UART isn't doing flow
1460 * control, which is currently the case. Hence, if it ever
1461 * takes longer than info->timeout, this is probably due to a
1462 * UART bug of some kind. So, we clamp the timeout parameter at
1463 * 2*info->timeout.
1464 */
1465 if (!timeout || timeout > 2*info->timeout)
1466 timeout = 2*info->timeout;
1467 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1468 printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
1469 printk("jiff=%lu...", jiffies);
1470 #endif
1471 while(!((lsr = custom.serdatr) & SDR_TSRE)) {
1472 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1473 printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
1474 #endif
1475 msleep_interruptible(jiffies_to_msecs(char_time));
1476 if (signal_pending(current))
1477 break;
1478 if (timeout && time_after(jiffies, orig_jiffies + timeout))
1479 break;
1480 }
1481 __set_current_state(TASK_RUNNING);
1482
1483 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1484 printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1485 #endif
1486 }
1487
1488 /*
1489 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1490 */
rs_hangup(struct tty_struct * tty)1491 static void rs_hangup(struct tty_struct *tty)
1492 {
1493 struct serial_state *info = tty->driver_data;
1494
1495 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1496 return;
1497
1498 rs_flush_buffer(tty);
1499 shutdown(tty, info);
1500 info->tport.count = 0;
1501 info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
1502 info->tport.tty = NULL;
1503 wake_up_interruptible(&info->tport.open_wait);
1504 }
1505
1506 /*
1507 * This routine is called whenever a serial port is opened. It
1508 * enables interrupts for a serial port, linking in its async structure into
1509 * the IRQ chain. It also performs the serial-specific
1510 * initialization for the tty structure.
1511 */
rs_open(struct tty_struct * tty,struct file * filp)1512 static int rs_open(struct tty_struct *tty, struct file * filp)
1513 {
1514 struct serial_state *info = rs_table + tty->index;
1515 struct tty_port *port = &info->tport;
1516 int retval;
1517
1518 port->count++;
1519 port->tty = tty;
1520 tty->driver_data = info;
1521 tty->port = port;
1522 if (serial_paranoia_check(info, tty->name, "rs_open"))
1523 return -ENODEV;
1524
1525 port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1526
1527 retval = startup(tty, info);
1528 if (retval) {
1529 return retval;
1530 }
1531
1532 return tty_port_block_til_ready(port, tty, filp);
1533 }
1534
1535 /*
1536 * /proc fs routines....
1537 */
1538
line_info(struct seq_file * m,int line,struct serial_state * state)1539 static inline void line_info(struct seq_file *m, int line,
1540 struct serial_state *state)
1541 {
1542 char stat_buf[30], control, status;
1543 unsigned long flags;
1544
1545 seq_printf(m, "%d: uart:amiga_builtin", line);
1546
1547 local_irq_save(flags);
1548 status = ciab.pra;
1549 control = (state->tport.flags & ASYNC_INITIALIZED) ? state->MCR : status;
1550 local_irq_restore(flags);
1551
1552 stat_buf[0] = 0;
1553 stat_buf[1] = 0;
1554 if(!(control & SER_RTS))
1555 strcat(stat_buf, "|RTS");
1556 if(!(status & SER_CTS))
1557 strcat(stat_buf, "|CTS");
1558 if(!(control & SER_DTR))
1559 strcat(stat_buf, "|DTR");
1560 if(!(status & SER_DSR))
1561 strcat(stat_buf, "|DSR");
1562 if(!(status & SER_DCD))
1563 strcat(stat_buf, "|CD");
1564
1565 if (state->quot)
1566 seq_printf(m, " baud:%d", state->baud_base / state->quot);
1567
1568 seq_printf(m, " tx:%d rx:%d", state->icount.tx, state->icount.rx);
1569
1570 if (state->icount.frame)
1571 seq_printf(m, " fe:%d", state->icount.frame);
1572
1573 if (state->icount.parity)
1574 seq_printf(m, " pe:%d", state->icount.parity);
1575
1576 if (state->icount.brk)
1577 seq_printf(m, " brk:%d", state->icount.brk);
1578
1579 if (state->icount.overrun)
1580 seq_printf(m, " oe:%d", state->icount.overrun);
1581
1582 /*
1583 * Last thing is the RS-232 status lines
1584 */
1585 seq_printf(m, " %s\n", stat_buf+1);
1586 }
1587
rs_proc_show(struct seq_file * m,void * v)1588 static int rs_proc_show(struct seq_file *m, void *v)
1589 {
1590 seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
1591 line_info(m, 0, &rs_table[0]);
1592 return 0;
1593 }
1594
rs_proc_open(struct inode * inode,struct file * file)1595 static int rs_proc_open(struct inode *inode, struct file *file)
1596 {
1597 return single_open(file, rs_proc_show, NULL);
1598 }
1599
1600 static const struct file_operations rs_proc_fops = {
1601 .owner = THIS_MODULE,
1602 .open = rs_proc_open,
1603 .read = seq_read,
1604 .llseek = seq_lseek,
1605 .release = single_release,
1606 };
1607
1608 /*
1609 * ---------------------------------------------------------------------
1610 * rs_init() and friends
1611 *
1612 * rs_init() is called at boot-time to initialize the serial driver.
1613 * ---------------------------------------------------------------------
1614 */
1615
1616 /*
1617 * This routine prints out the appropriate serial driver version
1618 * number, and identifies which options were configured into this
1619 * driver.
1620 */
show_serial_version(void)1621 static void show_serial_version(void)
1622 {
1623 printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
1624 }
1625
1626
1627 static const struct tty_operations serial_ops = {
1628 .open = rs_open,
1629 .close = rs_close,
1630 .write = rs_write,
1631 .put_char = rs_put_char,
1632 .flush_chars = rs_flush_chars,
1633 .write_room = rs_write_room,
1634 .chars_in_buffer = rs_chars_in_buffer,
1635 .flush_buffer = rs_flush_buffer,
1636 .ioctl = rs_ioctl,
1637 .throttle = rs_throttle,
1638 .unthrottle = rs_unthrottle,
1639 .set_termios = rs_set_termios,
1640 .stop = rs_stop,
1641 .start = rs_start,
1642 .hangup = rs_hangup,
1643 .break_ctl = rs_break,
1644 .send_xchar = rs_send_xchar,
1645 .wait_until_sent = rs_wait_until_sent,
1646 .tiocmget = rs_tiocmget,
1647 .tiocmset = rs_tiocmset,
1648 .get_icount = rs_get_icount,
1649 .proc_fops = &rs_proc_fops,
1650 };
1651
amiga_carrier_raised(struct tty_port * port)1652 static int amiga_carrier_raised(struct tty_port *port)
1653 {
1654 return !(ciab.pra & SER_DCD);
1655 }
1656
amiga_dtr_rts(struct tty_port * port,int raise)1657 static void amiga_dtr_rts(struct tty_port *port, int raise)
1658 {
1659 struct serial_state *info = container_of(port, struct serial_state,
1660 tport);
1661 unsigned long flags;
1662
1663 if (raise)
1664 info->MCR |= SER_DTR|SER_RTS;
1665 else
1666 info->MCR &= ~(SER_DTR|SER_RTS);
1667
1668 local_irq_save(flags);
1669 rtsdtr_ctrl(info->MCR);
1670 local_irq_restore(flags);
1671 }
1672
1673 static const struct tty_port_operations amiga_port_ops = {
1674 .carrier_raised = amiga_carrier_raised,
1675 .dtr_rts = amiga_dtr_rts,
1676 };
1677
1678 /*
1679 * The serial driver boot-time initialization code!
1680 */
amiga_serial_probe(struct platform_device * pdev)1681 static int __init amiga_serial_probe(struct platform_device *pdev)
1682 {
1683 unsigned long flags;
1684 struct serial_state * state;
1685 int error;
1686
1687 serial_driver = alloc_tty_driver(NR_PORTS);
1688 if (!serial_driver)
1689 return -ENOMEM;
1690
1691 show_serial_version();
1692
1693 /* Initialize the tty_driver structure */
1694
1695 serial_driver->driver_name = "amiserial";
1696 serial_driver->name = "ttyS";
1697 serial_driver->major = TTY_MAJOR;
1698 serial_driver->minor_start = 64;
1699 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1700 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1701 serial_driver->init_termios = tty_std_termios;
1702 serial_driver->init_termios.c_cflag =
1703 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1704 serial_driver->flags = TTY_DRIVER_REAL_RAW;
1705 tty_set_operations(serial_driver, &serial_ops);
1706
1707 state = rs_table;
1708 state->port = (int)&custom.serdatr; /* Just to give it a value */
1709 state->custom_divisor = 0;
1710 state->icount.cts = state->icount.dsr =
1711 state->icount.rng = state->icount.dcd = 0;
1712 state->icount.rx = state->icount.tx = 0;
1713 state->icount.frame = state->icount.parity = 0;
1714 state->icount.overrun = state->icount.brk = 0;
1715 tty_port_init(&state->tport);
1716 state->tport.ops = &amiga_port_ops;
1717 tty_port_link_device(&state->tport, serial_driver, 0);
1718
1719 error = tty_register_driver(serial_driver);
1720 if (error)
1721 goto fail_put_tty_driver;
1722
1723 printk(KERN_INFO "ttyS0 is the amiga builtin serial port\n");
1724
1725 /* Hardware set up */
1726
1727 state->baud_base = amiga_colorclock;
1728 state->xmit_fifo_size = 1;
1729
1730 /* set ISRs, and then disable the rx interrupts */
1731 error = request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
1732 if (error)
1733 goto fail_unregister;
1734
1735 error = request_irq(IRQ_AMIGA_RBF, ser_rx_int, 0,
1736 "serial RX", state);
1737 if (error)
1738 goto fail_free_irq;
1739
1740 local_irq_save(flags);
1741
1742 /* turn off Rx and Tx interrupts */
1743 custom.intena = IF_RBF | IF_TBE;
1744 mb();
1745
1746 /* clear any pending interrupt */
1747 custom.intreq = IF_RBF | IF_TBE;
1748 mb();
1749
1750 local_irq_restore(flags);
1751
1752 /*
1753 * set the appropriate directions for the modem control flags,
1754 * and clear RTS and DTR
1755 */
1756 ciab.ddra |= (SER_DTR | SER_RTS); /* outputs */
1757 ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR); /* inputs */
1758
1759 platform_set_drvdata(pdev, state);
1760
1761 return 0;
1762
1763 fail_free_irq:
1764 free_irq(IRQ_AMIGA_TBE, state);
1765 fail_unregister:
1766 tty_unregister_driver(serial_driver);
1767 fail_put_tty_driver:
1768 tty_port_destroy(&state->tport);
1769 put_tty_driver(serial_driver);
1770 return error;
1771 }
1772
amiga_serial_remove(struct platform_device * pdev)1773 static int __exit amiga_serial_remove(struct platform_device *pdev)
1774 {
1775 int error;
1776 struct serial_state *state = platform_get_drvdata(pdev);
1777
1778 /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
1779 if ((error = tty_unregister_driver(serial_driver)))
1780 printk("SERIAL: failed to unregister serial driver (%d)\n",
1781 error);
1782 put_tty_driver(serial_driver);
1783 tty_port_destroy(&state->tport);
1784
1785 free_irq(IRQ_AMIGA_TBE, state);
1786 free_irq(IRQ_AMIGA_RBF, state);
1787
1788 platform_set_drvdata(pdev, NULL);
1789
1790 return error;
1791 }
1792
1793 static struct platform_driver amiga_serial_driver = {
1794 .remove = __exit_p(amiga_serial_remove),
1795 .driver = {
1796 .name = "amiga-serial",
1797 .owner = THIS_MODULE,
1798 },
1799 };
1800
1801 module_platform_driver_probe(amiga_serial_driver, amiga_serial_probe);
1802
1803
1804 #if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE)
1805
1806 /*
1807 * ------------------------------------------------------------
1808 * Serial console driver
1809 * ------------------------------------------------------------
1810 */
1811
amiga_serial_putc(char c)1812 static void amiga_serial_putc(char c)
1813 {
1814 custom.serdat = (unsigned char)c | 0x100;
1815 while (!(custom.serdatr & 0x2000))
1816 barrier();
1817 }
1818
1819 /*
1820 * Print a string to the serial port trying not to disturb
1821 * any possible real use of the port...
1822 *
1823 * The console must be locked when we get here.
1824 */
serial_console_write(struct console * co,const char * s,unsigned count)1825 static void serial_console_write(struct console *co, const char *s,
1826 unsigned count)
1827 {
1828 unsigned short intena = custom.intenar;
1829
1830 custom.intena = IF_TBE;
1831
1832 while (count--) {
1833 if (*s == '\n')
1834 amiga_serial_putc('\r');
1835 amiga_serial_putc(*s++);
1836 }
1837
1838 custom.intena = IF_SETCLR | (intena & IF_TBE);
1839 }
1840
serial_console_device(struct console * c,int * index)1841 static struct tty_driver *serial_console_device(struct console *c, int *index)
1842 {
1843 *index = 0;
1844 return serial_driver;
1845 }
1846
1847 static struct console sercons = {
1848 .name = "ttyS",
1849 .write = serial_console_write,
1850 .device = serial_console_device,
1851 .flags = CON_PRINTBUFFER,
1852 .index = -1,
1853 };
1854
1855 /*
1856 * Register console.
1857 */
amiserial_console_init(void)1858 static int __init amiserial_console_init(void)
1859 {
1860 register_console(&sercons);
1861 return 0;
1862 }
1863 console_initcall(amiserial_console_init);
1864
1865 #endif /* CONFIG_SERIAL_CONSOLE && !MODULE */
1866
1867 MODULE_LICENSE("GPL");
1868 MODULE_ALIAS("platform:amiga-serial");
1869