1 /* $Id: su.c,v 1.54 2001/11/07 14:52:30 davem Exp $
2  * su.c: Small serial driver for keyboard/mouse interface on sparc32/PCI
3  *
4  * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
5  * Copyright (C) 1998-1999  Pete Zaitcev   (zaitcev@yahoo.com)
6  *
7  * This is mainly a variation of drivers/char/serial.c,
8  * credits go to authors mentioned therein.
9  *
10  * Fixed to use tty_get_baud_rate().
11  *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
12  */
13 
14 /*
15  * Configuration section.
16  */
17 #undef SERIAL_PARANOIA_CHECK
18 #define CONFIG_SERIAL_NOPAUSE_IO	/* Unused on sparc */
19 #define SERIAL_DO_RESTART
20 
21 /* Set of debugging defines */
22 
23 #undef SERIAL_DEBUG_INTR
24 #undef SERIAL_DEBUG_OPEN
25 #undef SERIAL_DEBUG_FLOW
26 #undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
27 #undef SERIAL_DEBUG_THROTTLE
28 
29 #define RS_ISR_PASS_LIMIT 256
30 
31 /*
32  * 0x20 is sun4m thing, Dave Redman heritage.
33  * See arch/sparc/kernel/irq.c.
34  */
35 #define IRQ_4M(n)	((n)|0x20)
36 
37 #if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
38 #define DBG_CNT(s)							\
39 do {									\
40 	printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n",		\
41 	       kdevname(tty->device), (info->flags), serial_refcount,	\
42 	       info->count,tty->count,s);				\
43 } while (0)
44 #else
45 #define DBG_CNT(s)
46 #endif
47 
48 /*
49  * End of serial driver configuration section.
50  */
51 #include <linux/config.h>
52 #include <linux/module.h>
53 #include <linux/errno.h>
54 #include <linux/signal.h>
55 #include <linux/sched.h>
56 #include <linux/interrupt.h>
57 #include <linux/tty.h>
58 #include <linux/tty_flip.h>
59 #include <linux/serial.h>
60 #include <linux/serialP.h>
61 #include <linux/serial_reg.h>
62 #include <linux/string.h>
63 #include <linux/fcntl.h>
64 #include <linux/ptrace.h>
65 #include <linux/ioport.h>
66 #include <linux/mm.h>
67 #include <linux/slab.h>
68 #include <linux/init.h>
69 #include <linux/bootmem.h>
70 #include <linux/delay.h>
71 #ifdef CONFIG_SERIAL_CONSOLE
72 #include <linux/console.h>
73 #include <linux/major.h>
74 #endif
75 #include <linux/sysrq.h>
76 
77 #include <asm/system.h>
78 #include <asm/oplib.h>
79 #include <asm/io.h>
80 #include <asm/ebus.h>
81 #ifdef CONFIG_SPARC64
82 #include <asm/isa.h>
83 #endif
84 #include <asm/irq.h>
85 #include <asm/uaccess.h>
86 #include <asm/bitops.h>
87 
88 #include "sunserial.h"
89 #include "sunkbd.h"
90 #include "sunmouse.h"
91 
92 /* We are on a NS PC87303 clocked with 24.0 MHz, which results
93  * in a UART clock of 1.8462 MHz.
94  */
95 #define BAUD_BASE	(1846200 / 16)
96 
97 #ifdef CONFIG_SERIAL_CONSOLE
98 extern int serial_console;
99 static struct console sercons;
100 int su_serial_console_init(void);
101 #endif
102 
103 enum su_type { SU_PORT_NONE, SU_PORT_MS, SU_PORT_KBD, SU_PORT_PORT };
104 static char *su_typev[] = { "???", "mouse", "kbd", "serial" };
105 
106 #define SU_PROPSIZE	128
107 
108 /*
109  * serial.c saves memory when it allocates async_info upon first open.
110  * We have parts of state structure together because we do call startup
111  * for keyboard and mouse.
112  */
113 struct su_struct {
114 	int		 magic;
115 	unsigned long	 port;
116 	int		 baud_base;
117 	int		 type;		/* Hardware type: e.g. 16550 */
118 	int		 irq;
119 	int		 flags;
120 	int		 line;
121 	int		 cflag;
122 
123 	enum su_type	 port_type;	/* Hookup type: e.g. mouse */
124 	int		 is_console;
125 	int		 port_node;
126 
127 	char		 name[16];
128 
129 	int		 xmit_fifo_size;
130 	int		 custom_divisor;
131 	unsigned short	 close_delay;
132 	unsigned short	 closing_wait;	/* time to wait before closing */
133 
134 	struct tty_struct 	*tty;
135 	int			read_status_mask;
136 	int			ignore_status_mask;
137 	int			timeout;
138 	int			quot;
139 	int			x_char;	/* xon/xoff character */
140 	int			IER; 	/* Interrupt Enable Register */
141 	int			MCR; 	/* Modem control register */
142 	unsigned long		event;
143 	int			blocked_open; /* # of blocked opens */
144 	long			session; /* Session of opening process */
145 	long			pgrp; /* pgrp of opening process */
146 	unsigned char 		*xmit_buf;
147 	int			xmit_head;
148 	int			xmit_tail;
149 	int			xmit_cnt;
150 	struct tq_struct	tqueue;
151 	wait_queue_head_t	open_wait;
152 	wait_queue_head_t	close_wait;
153 	wait_queue_head_t	delta_msr_wait;
154 
155 	int			count;
156 	struct async_icount	icount;
157 	struct termios		normal_termios, callout_termios;
158 	unsigned long		last_active;	/* For async_struct, to be */
159 };
160 
161 /*
162  * Scan status structure.
163  * "prop" is a local variable but it eats stack to keep it in each
164  * stack frame of a recursive procedure.
165  */
166 struct su_probe_scan {
167 	int msnode, kbnode;	/* PROM nodes for mouse and keyboard */
168 	int msx, kbx;		/* minors for mouse and keyboard */
169 	int devices;		/* scan index */
170 	char prop[SU_PROPSIZE];
171 };
172 
173 static char *serial_name = "PCIO serial driver";
174 static char serial_version[16];
175 
176 static DECLARE_TASK_QUEUE(tq_serial);
177 
178 static struct tty_driver serial_driver, callout_driver;
179 static int serial_refcount;
180 
181 /* number of characters left in xmit buffer before we ask for more */
182 #define WAKEUP_CHARS 256
183 
184 static void autoconfig(struct su_struct *info);
185 static void change_speed(struct su_struct *info, struct termios *old);
186 static void su_wait_until_sent(struct tty_struct *tty, int timeout);
187 
188 /*
189  * Here we define the default xmit fifo size used for each type of
190  * UART
191  */
192 static struct serial_uart_config uart_config[] = {
193 	{ "unknown", 1, 0 },
194 	{ "8250", 1, 0 },
195 	{ "16450", 1, 0 },
196 	{ "16550", 1, 0 },
197 	{ "16550A", 16, UART_CLEAR_FIFO | UART_USE_FIFO },
198 	{ "cirrus", 1, 0 },
199 	{ "ST16650", 1, UART_CLEAR_FIFO |UART_STARTECH },
200 	{ "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO |
201 		  UART_STARTECH },
202 	{ "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO},
203 	{ 0, 0}
204 };
205 
206 
207 #define NR_PORTS	4
208 
209 static struct su_struct su_table[NR_PORTS];
210 static struct tty_struct *serial_table[NR_PORTS];
211 static struct termios *serial_termios[NR_PORTS];
212 static struct termios *serial_termios_locked[NR_PORTS];
213 
214 #ifndef MIN
215 #define MIN(a,b)	((a) < (b) ? (a) : (b))
216 #endif
217 
218 /*
219  * tmp_buf is used as a temporary buffer by serial_write.  We need to
220  * lock it in case the copy_from_user blocks while swapping in a page,
221  * and some other program tries to do a serial write at the same time.
222  * Since the lock will only come under contention when the system is
223  * swapping and available memory is low, it makes sense to share one
224  * buffer across all the serial ports, since it significantly saves
225  * memory if large numbers of serial ports are open.
226  */
227 static unsigned char *tmp_buf;
228 static DECLARE_MUTEX(tmp_buf_sem);
229 
serial_paranoia_check(struct su_struct * info,kdev_t device,const char * routine)230 static inline int serial_paranoia_check(struct su_struct *info,
231 					kdev_t device, const char *routine)
232 {
233 #ifdef SERIAL_PARANOIA_CHECK
234 	static const char *badmagic = KERN_WARNING
235 		"Warning: bad magic number for serial struct (%s) in %s\n";
236 	static const char *badinfo = KERN_WARNING
237 		"Warning: null su_struct for (%s) in %s\n";
238 
239 	if (!info) {
240 		printk(badinfo, kdevname(device), routine);
241 		return 1;
242 	}
243 	if (info->magic != SERIAL_MAGIC) {
244 		printk(badmagic, kdevname(device), routine);
245 		return 1;
246 	}
247 #endif
248 	return 0;
249 }
250 
251 static inline
su_inb(struct su_struct * info,unsigned long offset)252 unsigned int su_inb(struct su_struct *info, unsigned long offset)
253 {
254 	return inb(info->port + offset);
255 }
256 
257 static inline void
su_outb(struct su_struct * info,unsigned long offset,int value)258 su_outb(struct su_struct *info, unsigned long offset, int value)
259 {
260 #ifndef __sparc_v9__
261 	/*
262 	 * MrCoffee has weird schematics: IRQ4 & P10(?) pins of SuperIO are
263 	 * connected with a gate then go to SlavIO. When IRQ4 goes tristated
264 	 * gate outputs a logical one. Since we use level triggered interrupts
265 	 * we have lockup and watchdog reset. We cannot mask IRQ because
266 	 * keyboard shares IRQ with us (Word has it as Bob Smelik's design).
267 	 * This problem is similar to what Alpha people suffer, see serial.c.
268 	 */
269 	if (offset == UART_MCR) value |= UART_MCR_OUT2;
270 #endif
271 	outb(value, info->port + offset);
272 }
273 
274 #define serial_in(info, off)		su_inb(info, off)
275 #define serial_inp(info, off)		su_inb(info, off)
276 #define serial_out(info, off, val)	su_outb(info, off, val)
277 #define serial_outp(info, off, val)	su_outb(info, off, val)
278 
279 /*
280  * ------------------------------------------------------------
281  * su_stop() and su_start()
282  *
283  * This routines are called before setting or resetting tty->stopped.
284  * They enable or disable transmitter interrupts, as necessary.
285  * ------------------------------------------------------------
286  */
su_stop(struct tty_struct * tty)287 static void su_stop(struct tty_struct *tty)
288 {
289 	struct su_struct *info = (struct su_struct *)tty->driver_data;
290 	unsigned long flags;
291 
292 	if (serial_paranoia_check(info, tty->device, "su_stop"))
293 		return;
294 
295 	save_flags(flags); cli();
296 	if (info->IER & UART_IER_THRI) {
297 		info->IER &= ~UART_IER_THRI;
298 		serial_out(info, UART_IER, info->IER);
299 	}
300 	restore_flags(flags);
301 }
302 
su_start(struct tty_struct * tty)303 static void su_start(struct tty_struct *tty)
304 {
305 	struct su_struct *info = (struct su_struct *)tty->driver_data;
306 	unsigned long flags;
307 
308 	if (serial_paranoia_check(info, tty->device, "su_start"))
309 		return;
310 
311 	save_flags(flags); cli();
312 	if (info->xmit_cnt && info->xmit_buf && !(info->IER & UART_IER_THRI)) {
313 		info->IER |= UART_IER_THRI;
314 		serial_out(info, UART_IER, info->IER);
315 	}
316 	restore_flags(flags);
317 }
318 
319 /*
320  * ----------------------------------------------------------------------
321  *
322  * Here starts the interrupt handling routines.  All of the following
323  * subroutines are declared as inline and are folded into
324  * su_interrupt().  They were separated out for readability's sake.
325  *
326  * Note: rs_interrupt() is a "fast" interrupt, which means that it
327  * runs with interrupts turned off.  People who may want to modify
328  * rs_interrupt() should try to keep the interrupt handler as fast as
329  * possible.  After you are done making modifications, it is not a bad
330  * idea to do:
331  *
332  * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
333  *
334  * and look at the resulting assemble code in serial.s.
335  *
336  * 				- Ted Ts'o (tytso@mit.edu), 7-Mar-93
337  * -----------------------------------------------------------------------
338  */
339 
340 /*
341  * This routine is used by the interrupt handler to schedule
342  * processing in the software interrupt portion of the driver.
343  */
344 static void
su_sched_event(struct su_struct * info,int event)345 su_sched_event(struct su_struct *info, int event)
346 {
347 	info->event |= 1 << event;
348 	queue_task(&info->tqueue, &tq_serial);
349 	mark_bh(SERIAL_BH);
350 }
351 
352 static void
receive_kbd_ms_chars(struct su_struct * info,struct pt_regs * regs,int is_brk)353 receive_kbd_ms_chars(struct su_struct *info, struct pt_regs *regs, int is_brk)
354 {
355 	unsigned char status = 0;
356 	unsigned char ch;
357 
358 	do {
359 		ch = serial_inp(info, UART_RX);
360 		if (info->port_type == SU_PORT_KBD) {
361 			if (ch == SUNKBD_RESET) {
362                         	l1a_state.kbd_id = 1;
363                         	l1a_state.l1_down = 0;
364                 	} else if (l1a_state.kbd_id) {
365                         	l1a_state.kbd_id = 0;
366                 	} else if (ch == SUNKBD_L1) {
367                         	l1a_state.l1_down = 1;
368                 	} else if (ch == (SUNKBD_L1|SUNKBD_UP)) {
369                         	l1a_state.l1_down = 0;
370                 	} else if (ch == SUNKBD_A && l1a_state.l1_down) {
371                         	/* whee... */
372                         	batten_down_hatches();
373                         	/* Continue execution... */
374                         	l1a_state.l1_down = 0;
375                         	l1a_state.kbd_id = 0;
376                         	return;
377                 	}
378                 	sunkbd_inchar(ch, regs);
379 		} else {
380 			sun_mouse_inbyte(ch, is_brk);
381 		}
382 
383 		status = su_inb(info, UART_LSR);
384 	} while (status & UART_LSR_DR);
385 }
386 
387 static void
receive_serial_chars(struct su_struct * info,int * status,struct pt_regs * regs)388 receive_serial_chars(struct su_struct *info, int *status, struct pt_regs *regs)
389 {
390 	struct tty_struct *tty = info->tty;
391 	unsigned char ch;
392 	int ignored = 0, saw_console_brk = 0;
393 	struct	async_icount *icount;
394 
395 	icount = &info->icount;
396 	do {
397 		ch = serial_inp(info, UART_RX);
398 		if (info->is_console &&
399 		    (ch == 0 || (*status &UART_LSR_BI)))
400 			saw_console_brk = 1;
401 		if (tty->flip.count >= TTY_FLIPBUF_SIZE)
402 			break;
403 		*tty->flip.char_buf_ptr = ch;
404 		icount->rx++;
405 
406 #ifdef SERIAL_DEBUG_INTR
407 		printk("D%02x:%02x.", ch, *status);
408 #endif
409 		*tty->flip.flag_buf_ptr = 0;
410 		if (*status & (UART_LSR_BI | UART_LSR_PE |
411 			       UART_LSR_FE | UART_LSR_OE)) {
412 			/*
413 			 * For statistics only
414 			 */
415 			if (*status & UART_LSR_BI) {
416 				*status &= ~(UART_LSR_FE | UART_LSR_PE);
417 				icount->brk++;
418 			} else if (*status & UART_LSR_PE)
419 				icount->parity++;
420 			else if (*status & UART_LSR_FE)
421 				icount->frame++;
422 			if (*status & UART_LSR_OE)
423 				icount->overrun++;
424 
425 			/*
426 			 * Now check to see if character should be
427 			 * ignored, and mask off conditions which
428 			 * should be ignored.
429 			 */
430 			if (*status & info->ignore_status_mask) {
431 				if (++ignored > 100) {
432 #ifdef SERIAL_DEBUG_INTR
433 					printk("ign100..");
434 #endif
435 					break;
436 				}
437 				goto ignore_char;
438 			}
439 			*status &= info->read_status_mask;
440 
441 			if (*status & (UART_LSR_BI)) {
442 #ifdef SERIAL_DEBUG_INTR
443 				printk("handling break....");
444 #endif
445 				*tty->flip.flag_buf_ptr = TTY_BREAK;
446 				if (info->flags & ASYNC_SAK)
447 					do_SAK(tty);
448 			} else if (*status & UART_LSR_PE)
449 				*tty->flip.flag_buf_ptr = TTY_PARITY;
450 			else if (*status & UART_LSR_FE)
451 				*tty->flip.flag_buf_ptr = TTY_FRAME;
452 			if (*status & UART_LSR_OE) {
453 				/*
454 				 * Overrun is special, since it's
455 				 * reported immediately, and doesn't
456 				 * affect the current character
457 				 */
458 				if (tty->flip.count < TTY_FLIPBUF_SIZE) {
459 					tty->flip.count++;
460 					tty->flip.flag_buf_ptr++;
461 					tty->flip.char_buf_ptr++;
462 					*tty->flip.flag_buf_ptr = TTY_OVERRUN;
463 				}
464 			}
465 		}
466 		tty->flip.flag_buf_ptr++;
467 		tty->flip.char_buf_ptr++;
468 		tty->flip.count++;
469 	ignore_char:
470 		*status = serial_inp(info, UART_LSR);
471 	} while (*status & UART_LSR_DR);
472 #ifdef SERIAL_DEBUG_INTR
473 	printk("E%02x.R%d", *status, tty->flip.count);
474 #endif
475 	tty_flip_buffer_push(tty);
476 	if (saw_console_brk != 0)
477 		batten_down_hatches();
478 }
479 
480 static void
transmit_chars(struct su_struct * info,int * intr_done)481 transmit_chars(struct su_struct *info, int *intr_done)
482 {
483 	int count;
484 
485 	if (info->x_char) {
486 		serial_outp(info, UART_TX, info->x_char);
487 		info->icount.tx++;
488 		info->x_char = 0;
489 		if (intr_done)
490 			*intr_done = 0;
491 		return;
492 	}
493 	if ((info->xmit_cnt <= 0) || info->tty->stopped ||
494 	    info->tty->hw_stopped) {
495 		info->IER &= ~UART_IER_THRI;
496 		serial_out(info, UART_IER, info->IER);
497 		return;
498 	}
499 
500 	count = info->xmit_fifo_size;
501 	do {
502 		serial_out(info, UART_TX, info->xmit_buf[info->xmit_tail++]);
503 		info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
504 		info->icount.tx++;
505 		if (--info->xmit_cnt <= 0)
506 			break;
507 	} while (--count > 0);
508 
509 	if (info->xmit_cnt < WAKEUP_CHARS)
510 		su_sched_event(info, RS_EVENT_WRITE_WAKEUP);
511 
512 #ifdef SERIAL_DEBUG_INTR
513 	printk("T%d...", info->xmit_cnt);
514 #endif
515 	if (intr_done)
516 		*intr_done = 0;
517 
518 	if (info->xmit_cnt <= 0) {
519 		info->IER &= ~UART_IER_THRI;
520 		serial_out(info, UART_IER, info->IER);
521 	}
522 }
523 
524 static void
check_modem_status(struct su_struct * info)525 check_modem_status(struct su_struct *info)
526 {
527 	int	status;
528 	struct	async_icount *icount;
529 
530 	status = serial_in(info, UART_MSR);
531 
532 	if (status & UART_MSR_ANY_DELTA) {
533 		icount = &info->icount;
534 		/* update input line counters */
535 		if (status & UART_MSR_TERI)
536 			icount->rng++;
537 		if (status & UART_MSR_DDSR)
538 			icount->dsr++;
539 		if (status & UART_MSR_DDCD) {
540 			icount->dcd++;
541 #ifdef CONFIG_HARD_PPS
542 			if ((info->flags & ASYNC_HARDPPS_CD) &&
543 			    (status & UART_MSR_DCD))
544 				hardpps();
545 #endif
546 		}
547 		if (status & UART_MSR_DCTS)
548 			icount->cts++;
549 		wake_up_interruptible(&info->delta_msr_wait);
550 	}
551 
552 	if ((info->flags & ASYNC_CHECK_CD) && (status & UART_MSR_DDCD)) {
553 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
554 		printk("ttys%d CD now %s...", info->line,
555 		       (status & UART_MSR_DCD) ? "on" : "off");
556 #endif
557 		if (status & UART_MSR_DCD)
558 			wake_up_interruptible(&info->open_wait);
559 		else if (!((info->flags & ASYNC_CALLOUT_ACTIVE) &&
560 			   (info->flags & ASYNC_CALLOUT_NOHUP))) {
561 #ifdef SERIAL_DEBUG_OPEN
562 			printk("doing serial hangup...");
563 #endif
564 			if (info->tty)
565 				tty_hangup(info->tty);
566 	}
567 	}
568 	if (info->flags & ASYNC_CTS_FLOW) {
569 		if (info->tty->hw_stopped) {
570 			if (status & UART_MSR_CTS) {
571 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
572 				printk("CTS tx start...");
573 #endif
574 				info->tty->hw_stopped = 0;
575 				info->IER |= UART_IER_THRI;
576 				serial_out(info, UART_IER, info->IER);
577 				su_sched_event(info, RS_EVENT_WRITE_WAKEUP);
578 				return;
579 			}
580 		} else {
581 			if (!(status & UART_MSR_CTS)) {
582 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
583 				printk("CTS tx stop...");
584 #endif
585 				info->tty->hw_stopped = 1;
586 				info->IER &= ~UART_IER_THRI;
587 				serial_out(info, UART_IER, info->IER);
588 			}
589 		}
590 	}
591 }
592 
593 /*
594  * This is the kbd/mouse serial driver's interrupt routine
595  */
596 static void
su_kbd_ms_interrupt(int irq,void * dev_id,struct pt_regs * regs)597 su_kbd_ms_interrupt(int irq, void *dev_id, struct pt_regs * regs)
598 {
599 	struct su_struct *info = (struct su_struct *)dev_id;
600 	unsigned char status;
601 
602 #ifdef SERIAL_DEBUG_INTR
603 	printk("su_kbd_ms_interrupt(%s)...", __irq_itoa(irq));
604 #endif
605 	if (!info)
606 		return;
607 
608 	if (serial_in(info, UART_IIR) & UART_IIR_NO_INT)
609 		return;
610 
611 	status = serial_inp(info, UART_LSR);
612 #ifdef SERIAL_DEBUG_INTR
613 	printk("status = %x...", status);
614 #endif
615 	if ((status & UART_LSR_DR) || (status & UART_LSR_BI))
616 		receive_kbd_ms_chars(info, regs,
617 				     (status & UART_LSR_BI) != 0);
618 
619 #ifdef SERIAL_DEBUG_INTR
620 	printk("end.\n");
621 #endif
622 }
623 
624 /*
625  * This is the serial driver's generic interrupt routine
626  */
627 static void
su_serial_interrupt(int irq,void * dev_id,struct pt_regs * regs)628 su_serial_interrupt(int irq, void *dev_id, struct pt_regs * regs)
629 {
630 	int status;
631 	struct su_struct *info;
632 	int pass_counter = 0;
633 
634 #ifdef SERIAL_DEBUG_INTR
635 	printk("su_serial_interrupt(%s)...", __irq_itoa(irq));
636 #endif
637 	info = (struct su_struct *)dev_id;
638 	if (!info || !info->tty) {
639 #ifdef SERIAL_DEBUG_INTR
640 		printk("strain\n");
641 #endif
642 		return;
643 	}
644 
645 	do {
646 		status = serial_inp(info, UART_LSR);
647 #ifdef SERIAL_DEBUG_INTR
648 		printk("status = %x...", status);
649 #endif
650 		if (status & UART_LSR_DR)
651 			receive_serial_chars(info, &status, regs);
652 		check_modem_status(info);
653 		if (status & UART_LSR_THRE)
654 			transmit_chars(info, 0);
655 
656 		if (pass_counter++ > RS_ISR_PASS_LIMIT) {
657 #ifdef SERIAL_DEBUG_INTR
658 			printk("rs loop break");
659 #endif
660 			break; 	/* Prevent infinite loops */
661 		}
662 	} while (!(serial_in(info, UART_IIR) & UART_IIR_NO_INT));
663 
664 	info->last_active = jiffies;
665 
666 #ifdef SERIAL_DEBUG_INTR
667 	printk("end.\n");
668 #endif
669 }
670 
671 /*
672  * -------------------------------------------------------------------
673  * Here ends the serial interrupt routines.
674  * -------------------------------------------------------------------
675  */
676 
677 /*
678  * This routine is used to handle the "bottom half" processing for the
679  * serial driver, known also the "software interrupt" processing.
680  * This processing is done at the kernel interrupt level, after the
681  * su_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
682  * is where time-consuming activities which can not be done in the
683  * interrupt driver proper are done; the interrupt driver schedules
684  * them using su_sched_event(), and they get done here.
685  */
do_serial_bh(void)686 static void do_serial_bh(void)
687 {
688 	run_task_queue(&tq_serial);
689 }
690 
do_softint(void * private_)691 static void do_softint(void *private_)
692 {
693 	struct su_struct	*info = (struct su_struct *) private_;
694 	struct tty_struct	*tty;
695 
696 	tty = info->tty;
697 	if (!tty)
698 		return;
699 
700 	if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
701 		tty_wakeup(tty);
702 	}
703 }
704 
705 /*
706  * ---------------------------------------------------------------
707  * Low level utility subroutines for the serial driver:  routines to
708  * figure out the appropriate timeout for an interrupt chain, routines
709  * to initialize and startup a serial port, and routines to shutdown a
710  * serial port.  Useful stuff like that.
711  * ---------------------------------------------------------------
712  */
713 
714 static int
startup(struct su_struct * info)715 startup(struct su_struct *info)
716 {
717 	unsigned long flags;
718 	int	retval=0;
719 	unsigned long page;
720 
721 	save_flags(flags);
722 	if (info->tty) {
723 		page = get_free_page(GFP_KERNEL);
724 		if (!page)
725 			return -ENOMEM;
726 
727 		cli();
728 
729 		if (info->flags & ASYNC_INITIALIZED) {
730 			free_page(page);
731 			goto errout;
732 		}
733 
734 		if (info->port == 0 || info->type == PORT_UNKNOWN) {
735 			set_bit(TTY_IO_ERROR, &info->tty->flags);
736 			free_page(page);
737 			goto errout;
738 		}
739 		if (info->xmit_buf)
740 			free_page(page);
741 		else
742 			info->xmit_buf = (unsigned char *) page;
743 	}
744 	cli();
745 
746 #ifdef SERIAL_DEBUG_OPEN
747 	printk("starting up ttys%d (irq %s)...", info->line,
748 	       __irq_itoa(info->irq));
749 #endif
750 
751 	if (uart_config[info->type].flags & UART_STARTECH) {
752 		/* Wake up UART */
753 		serial_outp(info, UART_LCR, 0xBF);
754 		serial_outp(info, UART_EFR, UART_EFR_ECB);
755 		serial_outp(info, UART_IER, 0);
756 		serial_outp(info, UART_EFR, 0);
757 		serial_outp(info, UART_LCR, 0);
758 	}
759 
760 	if (info->type == PORT_16750) {
761 		/* Wake up UART */
762 		serial_outp(info, UART_IER, 0);
763 	}
764 
765 	/*
766 	 * Clear the FIFO buffers and disable them
767 	 * (they will be reenabled in change_speed())
768 	 */
769 	if (uart_config[info->type].flags & UART_CLEAR_FIFO)
770 		serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR |
771 					     UART_FCR_CLEAR_XMIT));
772 
773 	/*
774 	 * At this point there's no way the LSR could still be 0xFF;
775 	 * if it is, then bail out, because there's likely no UART
776 	 * here.
777 	 */
778 	if (serial_inp(info, UART_LSR) == 0xff) {
779 		if (capable(CAP_SYS_ADMIN)) {
780 			if (info->tty)
781 				set_bit(TTY_IO_ERROR, &info->tty->flags);
782 		} else
783 			retval = -ENODEV;
784 		goto errout;
785 	}
786 
787 	/*
788 	 * Allocate the IRQ if necessary
789 	 */
790 	if (info->port_type != SU_PORT_PORT) {
791 		retval = request_irq(info->irq, su_kbd_ms_interrupt,
792 				     SA_SHIRQ, info->name, info);
793 	} else {
794 		retval = request_irq(info->irq, su_serial_interrupt,
795 				     SA_SHIRQ, info->name, info);
796 	}
797 	if (retval) {
798 		if (capable(CAP_SYS_ADMIN)) {
799 			if (info->tty)
800 				set_bit(TTY_IO_ERROR, &info->tty->flags);
801 			retval = 0;
802 		}
803 		goto errout;
804 	}
805 
806 	/*
807 	 * Clear the interrupt registers.
808 	 */
809 	(void) serial_inp(info, UART_RX);
810 	(void) serial_inp(info, UART_IIR);
811 	(void) serial_inp(info, UART_MSR);
812 
813 	/*
814 	 * Now, initialize the UART
815 	 */
816 	serial_outp(info, UART_LCR, UART_LCR_WLEN8);	/* reset DLAB */
817 
818 	info->MCR = 0;
819 	if (info->tty && info->tty->termios->c_cflag & CBAUD)
820 		info->MCR = UART_MCR_DTR | UART_MCR_RTS;
821 	if (info->irq != 0)
822 		info->MCR |= UART_MCR_OUT2;
823 	serial_outp(info, UART_MCR, info->MCR);
824 
825 	/*
826 	 * Finally, enable interrupts
827 	 */
828 	info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
829 	serial_outp(info, UART_IER, info->IER);	/* enable interrupts */
830 
831 	/*
832 	 * And clear the interrupt registers again for luck.
833 	 */
834 	(void)serial_inp(info, UART_LSR);
835 	(void)serial_inp(info, UART_RX);
836 	(void)serial_inp(info, UART_IIR);
837 	(void)serial_inp(info, UART_MSR);
838 
839 	if (info->tty)
840 		clear_bit(TTY_IO_ERROR, &info->tty->flags);
841 	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
842 
843 	/*
844 	 * Set up the tty->alt_speed kludge
845 	 */
846 	if (info->tty) {
847 		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
848 			info->tty->alt_speed = 57600;
849 		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
850 			info->tty->alt_speed = 115200;
851 		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
852 			info->tty->alt_speed = 230400;
853 		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
854 			info->tty->alt_speed = 460800;
855 	}
856 
857 	/*
858 	 * and set the speed of the serial port
859 	 */
860 	change_speed(info, 0);
861 
862 	info->flags |= ASYNC_INITIALIZED;
863 	restore_flags(flags);
864 	return 0;
865 
866 errout:
867 	restore_flags(flags);
868 	return retval;
869 }
870 
871 /*
872  * This routine will shutdown a serial port; interrupts are disabled, and
873  * DTR is dropped if the hangup on close termio flag is on.
874  */
875 static void
shutdown(struct su_struct * info)876 shutdown(struct su_struct *info)
877 {
878 	unsigned long	flags;
879 
880 	if (!(info->flags & ASYNC_INITIALIZED))
881 		return;
882 
883 	save_flags(flags); cli(); /* Disable interrupts */
884 
885 	/*
886 	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
887 	 * here so the queue might never be waken up
888 	 */
889 	wake_up_interruptible(&info->delta_msr_wait);
890 
891 	/*
892 	 * Free the IRQ, if necessary
893 	 */
894 	free_irq(info->irq, info);
895 
896 	if (info->xmit_buf) {
897 		free_page((unsigned long) info->xmit_buf);
898 		info->xmit_buf = 0;
899 	}
900 
901 	info->IER = 0;
902 	serial_outp(info, UART_IER, 0x00);	/* disable all intrs */
903 	info->MCR &= ~UART_MCR_OUT2;
904 
905 	/* disable break condition */
906 	serial_out(info, UART_LCR, serial_inp(info, UART_LCR) & ~UART_LCR_SBC);
907 
908 	if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
909 		info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
910 	serial_outp(info, UART_MCR, info->MCR);
911 
912 	/* disable FIFO's */
913 	serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR |
914 				     UART_FCR_CLEAR_XMIT));
915 	(void)serial_in(info, UART_RX);    /* read data port to reset things */
916 
917 	if (info->tty)
918 		set_bit(TTY_IO_ERROR, &info->tty->flags);
919 
920 	if (uart_config[info->type].flags & UART_STARTECH) {
921 		/* Arrange to enter sleep mode */
922 		serial_outp(info, UART_LCR, 0xBF);
923 		serial_outp(info, UART_EFR, UART_EFR_ECB);
924 		serial_outp(info, UART_IER, UART_IERX_SLEEP);
925 		serial_outp(info, UART_LCR, 0);
926 	}
927 	if (info->type == PORT_16750) {
928 		/* Arrange to enter sleep mode */
929 		serial_outp(info, UART_IER, UART_IERX_SLEEP);
930 	}
931 	info->flags &= ~ASYNC_INITIALIZED;
932 	restore_flags(flags);
933 }
934 
935 static int
su_get_baud_rate(struct su_struct * info)936 su_get_baud_rate(struct su_struct *info)
937 {
938 	static struct tty_struct c_tty;
939 	static struct termios c_termios;
940 
941 	if (info->tty)
942 		return tty_get_baud_rate(info->tty);
943 
944 	memset(&c_tty, 0, sizeof(c_tty));
945 	memset(&c_termios, 0, sizeof(c_termios));
946 	c_tty.termios = &c_termios;
947 	c_termios.c_cflag = info->cflag;
948 
949 	return tty_get_baud_rate(&c_tty);
950 }
951 
952 /*
953  * This routine is called to set the UART divisor registers to match
954  * the specified baud rate for a serial port.
955  */
956 static void
change_speed(struct su_struct * info,struct termios * old_termios)957 change_speed(struct su_struct *info,
958 	     struct termios *old_termios)
959 {
960 	int		quot = 0, baud;
961 	unsigned int	cval, fcr = 0;
962 	int		bits;
963 	unsigned long	flags;
964 
965 	if (info->port_type == SU_PORT_PORT) {
966 		if (!info->tty || !info->tty->termios)
967 			return;
968 		if (!info->port)
969 			return;
970 		info->cflag = info->tty->termios->c_cflag;
971 	}
972 
973 	/* byte size and parity */
974 	switch (info->cflag & CSIZE) {
975 	      case CS5: cval = 0x00; bits = 7; break;
976 	      case CS6: cval = 0x01; bits = 8; break;
977 	      case CS7: cval = 0x02; bits = 9; break;
978 	      case CS8: cval = 0x03; bits = 10; break;
979 		/* Never happens, but GCC is too dumb to figure it out */
980 	      default:  cval = 0x00; bits = 7; break;
981 	}
982 	if (info->cflag & CSTOPB) {
983 		cval |= 0x04;
984 		bits++;
985 	}
986 	if (info->cflag & PARENB) {
987 		cval |= UART_LCR_PARITY;
988 		bits++;
989 	}
990 	if (!(info->cflag & PARODD))
991 		cval |= UART_LCR_EPAR;
992 #ifdef CMSPAR
993 	if (info->cflag & CMSPAR)
994 		cval |= UART_LCR_SPAR;
995 #endif
996 
997 	/* Determine divisor based on baud rate */
998 	baud = su_get_baud_rate(info);
999 	if (baud == 38400 &&
1000 	    ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
1001 		quot = info->custom_divisor;
1002 	else {
1003 		if (baud == 134)
1004 			/* Special case since 134 is really 134.5 */
1005 			quot = (2 * info->baud_base / 269);
1006 		else if (baud)
1007 			quot = info->baud_base / baud;
1008 	}
1009 	/* If the quotient is zero refuse the change */
1010 	if (!quot && old_termios) {
1011 		info->tty->termios->c_cflag &= ~CBAUD;
1012 		info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
1013 		baud = tty_get_baud_rate(info->tty);
1014 		if (!baud)
1015 			baud = 9600;
1016 		if (baud == 38400 &&
1017 		    ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
1018 			quot = info->custom_divisor;
1019 		else {
1020 			if (baud == 134)
1021 				/* Special case since 134 is really 134.5 */
1022 				quot = (2*info->baud_base / 269);
1023 			else if (baud)
1024 				quot = info->baud_base / baud;
1025 		}
1026 	}
1027 	/* As a last resort, if the quotient is zero, default to 9600 bps */
1028 	if (!quot)
1029 		quot = info->baud_base / 9600;
1030 	info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / info->baud_base);
1031 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
1032 
1033 	/* Set up FIFO's */
1034 	if (uart_config[info->type].flags & UART_USE_FIFO) {
1035 		if ((info->baud_base / quot) < 9600)
1036 			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
1037 		else
1038 			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_8;
1039 	}
1040 	if (info->type == PORT_16750)
1041 		fcr |= UART_FCR7_64BYTE;
1042 
1043 	/* CTS flow control flag and modem status interrupts */
1044 	info->IER &= ~UART_IER_MSI;
1045 	if (info->flags & ASYNC_HARDPPS_CD)
1046 		info->IER |= UART_IER_MSI;
1047 	if (info->cflag & CRTSCTS) {
1048 		info->flags |= ASYNC_CTS_FLOW;
1049 		info->IER |= UART_IER_MSI;
1050 	} else
1051 		info->flags &= ~ASYNC_CTS_FLOW;
1052 	if (info->cflag & CLOCAL)
1053 		info->flags &= ~ASYNC_CHECK_CD;
1054 	else {
1055 		info->flags |= ASYNC_CHECK_CD;
1056 		info->IER |= UART_IER_MSI;
1057 	}
1058 	serial_out(info, UART_IER, info->IER);
1059 
1060 	/*
1061 	 * Set up parity check flag
1062 	 */
1063 	if (info->tty) {
1064 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
1065 
1066 		info->read_status_mask = UART_LSR_OE | UART_LSR_THRE |
1067 					 UART_LSR_DR;
1068 		if (I_INPCK(info->tty))
1069 			info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
1070 		if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
1071 			info->read_status_mask |= UART_LSR_BI;
1072 
1073 		/*
1074 		 * Characters to ignore
1075 		 */
1076 		info->ignore_status_mask = 0;
1077 		if (I_IGNPAR(info->tty))
1078 			info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
1079 		if (I_IGNBRK(info->tty)) {
1080 			info->ignore_status_mask |= UART_LSR_BI;
1081 			/*
1082 			 * If we're ignore parity and break indicators, ignore
1083 			 * overruns too.  (For real raw support).
1084 			 */
1085 			if (I_IGNPAR(info->tty))
1086 				info->ignore_status_mask |= UART_LSR_OE;
1087 		}
1088 		/*
1089 		 * !!! ignore all characters if CREAD is not set
1090 		 */
1091 		if ((info->cflag & CREAD) == 0)
1092 			info->ignore_status_mask |= UART_LSR_DR;
1093 	}
1094 
1095 	save_flags(flags); cli();
1096 	if (uart_config[info->type].flags & UART_STARTECH) {
1097 		serial_outp(info, UART_LCR, 0xBF);
1098 		serial_outp(info, UART_EFR,
1099 			    (info->cflag & CRTSCTS) ? UART_EFR_CTS : 0);
1100 	}
1101 	serial_outp(info, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
1102 	serial_outp(info, UART_DLL, quot & 0xff);	/* LS of divisor */
1103 	serial_outp(info, UART_DLM, quot >> 8);		/* MS of divisor */
1104 	if (info->type == PORT_16750)
1105 		serial_outp(info, UART_FCR, fcr); 	/* set fcr */
1106 	serial_outp(info, UART_LCR, cval);		/* reset DLAB */
1107 	if (info->type != PORT_16750)
1108 		serial_outp(info, UART_FCR, fcr); 	/* set fcr */
1109 	restore_flags(flags);
1110 	info->quot = quot;
1111 }
1112 
1113 static void
su_put_char(struct tty_struct * tty,unsigned char ch)1114 su_put_char(struct tty_struct *tty, unsigned char ch)
1115 {
1116 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1117 	unsigned long flags;
1118 
1119 	if (serial_paranoia_check(info, tty->device, "su_put_char"))
1120 		return;
1121 
1122 	if (!tty || !info->xmit_buf)
1123 		return;
1124 
1125 	save_flags(flags); cli();
1126 	if (info->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
1127 		restore_flags(flags);
1128 		return;
1129 	}
1130 
1131 	info->xmit_buf[info->xmit_head++] = ch;
1132 	info->xmit_head &= SERIAL_XMIT_SIZE-1;
1133 	info->xmit_cnt++;
1134 	restore_flags(flags);
1135 }
1136 
su_put_char_kbd(unsigned char c)1137 static void su_put_char_kbd(unsigned char c)
1138 {
1139 	struct su_struct *info = su_table;
1140 	int lsr;
1141 
1142 	if (info->port_type != SU_PORT_KBD)
1143 		++info;
1144 	if (info->port_type != SU_PORT_KBD)
1145 		return;
1146 
1147 	do {
1148 		lsr = serial_in(info, UART_LSR);
1149 	} while (!(lsr & UART_LSR_THRE));
1150 
1151 	/* Send the character out. */
1152 	su_outb(info, UART_TX, c);
1153 }
1154 
1155 static void
su_change_mouse_baud(int baud)1156 su_change_mouse_baud(int baud)
1157 {
1158 	struct su_struct *info = su_table;
1159 
1160 	if (info->port_type != SU_PORT_MS)
1161 		++info;
1162 	if (info->port_type != SU_PORT_MS)
1163 		return;
1164 
1165 	info->cflag &= ~CBAUD;
1166 	switch (baud) {
1167 		case 1200:
1168 			info->cflag |= B1200;
1169 			break;
1170 		case 2400:
1171 			info->cflag |= B2400;
1172 			break;
1173 		case 4800:
1174 			info->cflag |= B4800;
1175 			break;
1176 		case 9600:
1177 			info->cflag |= B9600;
1178 			break;
1179 		default:
1180 			printk("su_change_mouse_baud: unknown baud rate %d, "
1181 			       "defaulting to 1200\n", baud);
1182 			info->cflag |= 1200;
1183 			break;
1184 	}
1185 	change_speed(info, 0);
1186 }
1187 
1188 static void
su_flush_chars(struct tty_struct * tty)1189 su_flush_chars(struct tty_struct *tty)
1190 {
1191 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1192 	unsigned long flags;
1193 
1194 	if (serial_paranoia_check(info, tty->device, "su_flush_chars"))
1195 		return;
1196 
1197 	if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
1198 	    !info->xmit_buf)
1199 		return;
1200 
1201 	save_flags(flags); cli();
1202 	info->IER |= UART_IER_THRI;
1203 	serial_out(info, UART_IER, info->IER);
1204 	restore_flags(flags);
1205 }
1206 
1207 static int
su_write(struct tty_struct * tty,int from_user,const unsigned char * buf,int count)1208 su_write(struct tty_struct * tty, int from_user,
1209 		    const unsigned char *buf, int count)
1210 {
1211 	int	c, ret = 0;
1212 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1213 	unsigned long flags;
1214 
1215 	if (serial_paranoia_check(info, tty->device, "su_write"))
1216 		return 0;
1217 
1218 	if (!tty || !info->xmit_buf || !tmp_buf)
1219 		return 0;
1220 
1221 	save_flags(flags);
1222 	if (from_user) {
1223 		down(&tmp_buf_sem);
1224 		while (1) {
1225 			c = MIN(count,
1226 				MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
1227 				    SERIAL_XMIT_SIZE - info->xmit_head));
1228 			if (c <= 0)
1229 				break;
1230 
1231 			c -= copy_from_user(tmp_buf, buf, c);
1232 			if (!c) {
1233 				if (!ret)
1234 					ret = -EFAULT;
1235 				break;
1236 			}
1237 			cli();
1238 			c = MIN(c, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
1239 				       SERIAL_XMIT_SIZE - info->xmit_head));
1240 			memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
1241 			info->xmit_head = ((info->xmit_head + c) &
1242 					   (SERIAL_XMIT_SIZE-1));
1243 			info->xmit_cnt += c;
1244 			restore_flags(flags);
1245 			buf += c;
1246 			count -= c;
1247 			ret += c;
1248 		}
1249 		up(&tmp_buf_sem);
1250 	} else {
1251 		while (1) {
1252 			cli();
1253 			c = MIN(count,
1254 				MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
1255 				    SERIAL_XMIT_SIZE - info->xmit_head));
1256 			if (c <= 0) {
1257 				restore_flags(flags);
1258 				break;
1259 			}
1260 			memcpy(info->xmit_buf + info->xmit_head, buf, c);
1261 			info->xmit_head = ((info->xmit_head + c) &
1262 					   (SERIAL_XMIT_SIZE-1));
1263 			info->xmit_cnt += c;
1264 			restore_flags(flags);
1265 			buf += c;
1266 			count -= c;
1267 			ret += c;
1268 		}
1269 	}
1270 	if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
1271 	    !(info->IER & UART_IER_THRI)) {
1272 		info->IER |= UART_IER_THRI;
1273 		serial_out(info, UART_IER, info->IER);
1274 	}
1275 	return ret;
1276 }
1277 
1278 static int
su_write_room(struct tty_struct * tty)1279 su_write_room(struct tty_struct *tty)
1280 {
1281 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1282 	int	ret;
1283 
1284 	if (serial_paranoia_check(info, tty->device, "su_write_room"))
1285 		return 0;
1286 	ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
1287 	if (ret < 0)
1288 		ret = 0;
1289 	return ret;
1290 }
1291 
1292 static int
su_chars_in_buffer(struct tty_struct * tty)1293 su_chars_in_buffer(struct tty_struct *tty)
1294 {
1295 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1296 
1297 	if (serial_paranoia_check(info, tty->device, "su_chars_in_buffer"))
1298 		return 0;
1299 	return info->xmit_cnt;
1300 }
1301 
1302 static void
su_flush_buffer(struct tty_struct * tty)1303 su_flush_buffer(struct tty_struct *tty)
1304 {
1305 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1306 	unsigned long flags;
1307 
1308 	if (serial_paranoia_check(info, tty->device, "su_flush_buffer"))
1309 		return;
1310 	save_flags(flags); cli();
1311 	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
1312 	restore_flags(flags);
1313 	tty_wakeup(tty);
1314 }
1315 
1316 /*
1317  * This function is used to send a high-priority XON/XOFF character to
1318  * the device
1319  */
1320 static void
su_send_xchar(struct tty_struct * tty,char ch)1321 su_send_xchar(struct tty_struct *tty, char ch)
1322 {
1323 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1324 
1325 	if (serial_paranoia_check(info, tty->device, "su_send_char"))
1326 		return;
1327 
1328 	if (!(info->flags & ASYNC_INITIALIZED))
1329 		return;
1330 
1331 	info->x_char = ch;
1332 	if (ch) {
1333 		/* Make sure transmit interrupts are on */
1334 		info->IER |= UART_IER_THRI;
1335 		serial_out(info, UART_IER, info->IER);
1336 	}
1337 }
1338 
1339 /*
1340  * ------------------------------------------------------------
1341  * su_throttle()
1342  *
1343  * This routine is called by the upper-layer tty layer to signal that
1344  * incoming characters should be throttled.
1345  * ------------------------------------------------------------
1346  */
1347 static void
su_throttle(struct tty_struct * tty)1348 su_throttle(struct tty_struct * tty)
1349 {
1350 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1351 	unsigned long flags;
1352 #ifdef SERIAL_DEBUG_THROTTLE
1353 	char	buf[64];
1354 
1355 	printk("throttle %s: %d....\n", tty_name(tty, buf),
1356 	       tty->ldisc.chars_in_buffer(tty));
1357 #endif
1358 
1359 	if (serial_paranoia_check(info, tty->device, "su_throttle"))
1360 		return;
1361 
1362 	if (I_IXOFF(tty))
1363 		su_send_xchar(tty, STOP_CHAR(tty));
1364 
1365 	if (tty->termios->c_cflag & CRTSCTS)
1366 		info->MCR &= ~UART_MCR_RTS;
1367 
1368 	save_flags(flags); cli();
1369 	serial_out(info, UART_MCR, info->MCR);
1370 	restore_flags(flags);
1371 }
1372 
1373 static void
su_unthrottle(struct tty_struct * tty)1374 su_unthrottle(struct tty_struct * tty)
1375 {
1376 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1377 	unsigned long flags;
1378 #ifdef SERIAL_DEBUG_THROTTLE
1379 	char	buf[64];
1380 
1381 	printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1382 	       tty->ldisc.chars_in_buffer(tty));
1383 #endif
1384 
1385 	if (serial_paranoia_check(info, tty->device, "su_unthrottle"))
1386 		return;
1387 
1388 	if (I_IXOFF(tty)) {
1389 		if (info->x_char)
1390 			info->x_char = 0;
1391 		else
1392 			su_send_xchar(tty, START_CHAR(tty));
1393 	}
1394 	if (tty->termios->c_cflag & CRTSCTS)
1395 		info->MCR |= UART_MCR_RTS;
1396 	save_flags(flags); cli();
1397 	serial_out(info, UART_MCR, info->MCR);
1398 	restore_flags(flags);
1399 }
1400 
1401 /*
1402  * ------------------------------------------------------------
1403  * su_ioctl() and friends
1404  * ------------------------------------------------------------
1405  */
1406 
1407 /*
1408  * get_serial_info - handle TIOCGSERIAL ioctl()
1409  *
1410  * Purpose: Return standard serial struct information about
1411  *          a serial port handled by this driver.
1412  *
1413  * Added:   11-May-2001 Lars Kellogg-Stedman <lars@larsshack.org>
1414  */
get_serial_info(struct su_struct * info,struct serial_struct * retinfo)1415 static int get_serial_info(struct su_struct * info,
1416 			   struct serial_struct * retinfo)
1417 {
1418 	struct serial_struct	tmp;
1419 
1420 	if (!retinfo)
1421 		return -EFAULT;
1422 	memset(&tmp, 0, sizeof(tmp));
1423 
1424 	tmp.type		= info->type;
1425 	tmp.line		= info->line;
1426 	tmp.port		= info->port;
1427 	tmp.irq			= info->irq;
1428 	tmp.flags		= info->flags;
1429 	tmp.xmit_fifo_size	= info->xmit_fifo_size;
1430 	tmp.baud_base		= info->baud_base;
1431 	tmp.close_delay		= info->close_delay;
1432 	tmp.closing_wait	= info->closing_wait;
1433 	tmp.custom_divisor	= info->custom_divisor;
1434 	tmp.hub6		= 0;
1435 
1436 	if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1437 		return -EFAULT;
1438 
1439 	return 0;
1440 }
1441 
1442 /*
1443  * get_lsr_info - get line status register info
1444  *
1445  * Purpose: Let user call ioctl() to get info when the UART physically
1446  * 	    is emptied.  On bus types like RS485, the transmitter must
1447  * 	    release the bus after transmitting. This must be done when
1448  * 	    the transmit shift register is empty, not be done when the
1449  * 	    transmit holding register is empty.  This functionality
1450  * 	    allows an RS485 driver to be written in user space.
1451  */
1452 static int
get_lsr_info(struct su_struct * info,unsigned int * value)1453 get_lsr_info(struct su_struct * info, unsigned int *value)
1454 {
1455 	unsigned char status;
1456 	unsigned int result;
1457 	unsigned long flags;
1458 
1459 	save_flags(flags); cli();
1460 	status = serial_in(info, UART_LSR);
1461 	restore_flags(flags);
1462 	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1463 	return put_user(result,value);
1464 }
1465 
1466 
1467 static int
get_modem_info(struct su_struct * info,unsigned int * value)1468 get_modem_info(struct su_struct * info, unsigned int *value)
1469 {
1470 	unsigned char control, status;
1471 	unsigned int result;
1472 	unsigned long flags;
1473 
1474 	control = info->MCR;
1475 	save_flags(flags); cli();
1476 	status = serial_in(info, UART_MSR);
1477 	restore_flags(flags);
1478 	result =  ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
1479 		| ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
1480 #ifdef TIOCM_OUT1
1481 		| ((control & UART_MCR_OUT1) ? TIOCM_OUT1 : 0)
1482 		| ((control & UART_MCR_OUT2) ? TIOCM_OUT2 : 0)
1483 #endif
1484 		| ((status  & UART_MSR_DCD) ? TIOCM_CAR : 0)
1485 		| ((status  & UART_MSR_RI) ? TIOCM_RNG : 0)
1486 		| ((status  & UART_MSR_DSR) ? TIOCM_DSR : 0)
1487 		| ((status  & UART_MSR_CTS) ? TIOCM_CTS : 0);
1488 	return put_user(result,value);
1489 }
1490 
1491 static int
set_modem_info(struct su_struct * info,unsigned int cmd,unsigned int * value)1492 set_modem_info(struct su_struct * info, unsigned int cmd, unsigned int *value)
1493 {
1494 	unsigned int arg;
1495 	unsigned long flags;
1496 
1497 	if (get_user(arg, value))
1498 		return -EFAULT;
1499 	switch (cmd) {
1500 	case TIOCMBIS:
1501 		if (arg & TIOCM_RTS)
1502 			info->MCR |= UART_MCR_RTS;
1503 		if (arg & TIOCM_DTR)
1504 			info->MCR |= UART_MCR_DTR;
1505 #ifdef TIOCM_OUT1
1506 		if (arg & TIOCM_OUT1)
1507 			info->MCR |= UART_MCR_OUT1;
1508 		if (arg & TIOCM_OUT2)
1509 			info->MCR |= UART_MCR_OUT2;
1510 #endif
1511 		break;
1512 	case TIOCMBIC:
1513 		if (arg & TIOCM_RTS)
1514 			info->MCR &= ~UART_MCR_RTS;
1515 		if (arg & TIOCM_DTR)
1516 			info->MCR &= ~UART_MCR_DTR;
1517 #ifdef TIOCM_OUT1
1518 		if (arg & TIOCM_OUT1)
1519 			info->MCR &= ~UART_MCR_OUT1;
1520 		if (arg & TIOCM_OUT2)
1521 			info->MCR &= ~UART_MCR_OUT2;
1522 #endif
1523 		break;
1524 	case TIOCMSET:
1525 		info->MCR = ((info->MCR & ~(UART_MCR_RTS |
1526 #ifdef TIOCM_OUT1
1527 					    UART_MCR_OUT1 |
1528 					    UART_MCR_OUT2 |
1529 #endif
1530 					    UART_MCR_DTR))
1531 			     | ((arg & TIOCM_RTS) ? UART_MCR_RTS : 0)
1532 #ifdef TIOCM_OUT1
1533 			     | ((arg & TIOCM_OUT1) ? UART_MCR_OUT1 : 0)
1534 			     | ((arg & TIOCM_OUT2) ? UART_MCR_OUT2 : 0)
1535 #endif
1536 			     | ((arg & TIOCM_DTR) ? UART_MCR_DTR : 0));
1537 		break;
1538 	default:
1539 		return -EINVAL;
1540 	}
1541 	save_flags(flags); cli();
1542 	serial_out(info, UART_MCR, info->MCR);
1543 	restore_flags(flags);
1544 	return 0;
1545 }
1546 
1547 /*
1548  * su_break() --- routine which turns the break handling on or off
1549  */
1550 static void
su_break(struct tty_struct * tty,int break_state)1551 su_break(struct tty_struct *tty, int break_state)
1552 {
1553 	struct su_struct * info = (struct su_struct *)tty->driver_data;
1554 	unsigned long flags;
1555 
1556 	if (serial_paranoia_check(info, tty->device, "su_break"))
1557 		return;
1558 
1559 	if (!info->port)
1560 		return;
1561 	save_flags(flags); cli();
1562 	if (break_state == -1)
1563 		serial_out(info, UART_LCR,
1564 			   serial_inp(info, UART_LCR) | UART_LCR_SBC);
1565 	else
1566 		serial_out(info, UART_LCR,
1567 			   serial_inp(info, UART_LCR) & ~UART_LCR_SBC);
1568 	restore_flags(flags);
1569 }
1570 
1571 static int
su_ioctl(struct tty_struct * tty,struct file * file,unsigned int cmd,unsigned long arg)1572 su_ioctl(struct tty_struct *tty, struct file * file,
1573 		    unsigned int cmd, unsigned long arg)
1574 {
1575 	struct su_struct * info = (struct su_struct *)tty->driver_data;
1576 	struct async_icount cprev, cnow;	/* kernel counter temps */
1577 	struct serial_icounter_struct *p_cuser;	/* user space */
1578 
1579 	if (serial_paranoia_check(info, tty->device, "su_ioctl"))
1580 		return -ENODEV;
1581 
1582 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1583 	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
1584 	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1585 		if (tty->flags & (1 << TTY_IO_ERROR))
1586 		    return -EIO;
1587 	}
1588 
1589 	switch (cmd) {
1590 		case TIOCMGET:
1591 			return get_modem_info(info, (unsigned int *) arg);
1592 		case TIOCMBIS:
1593 		case TIOCMBIC:
1594 		case TIOCMSET:
1595 			return set_modem_info(info, cmd, (unsigned int *) arg);
1596 
1597 		case TIOCGSERIAL:
1598 			return get_serial_info(info, (struct serial_struct *)arg);
1599 
1600 		case TIOCSERGETLSR: /* Get line status register */
1601 			return get_lsr_info(info, (unsigned int *) arg);
1602 
1603 #if 0
1604 		case TIOCSERGSTRUCT:
1605 			if (copy_to_user((struct async_struct *) arg,
1606 					 info, sizeof(struct async_struct)))
1607 				return -EFAULT;
1608 			return 0;
1609 #endif
1610 
1611 		/*
1612 		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1613 		 * - mask passed in arg for lines of interest
1614  		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1615 		 * Caller should use TIOCGICOUNT to see which one it was
1616 		 */
1617 		case TIOCMIWAIT:
1618 			cli();
1619 			/* note the counters on entry */
1620 			cprev = info->icount;
1621 			sti();
1622 			while (1) {
1623 				interruptible_sleep_on(&info->delta_msr_wait);
1624 				/* see if a signal did it */
1625 				if (signal_pending(current))
1626 					return -ERESTARTSYS;
1627 				cli();
1628 				cnow = info->icount; /* atomic copy */
1629 				sti();
1630 				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
1631 				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1632 					return -EIO; /* no change => error */
1633 				if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1634 				     ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1635 				     ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
1636 				     ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1637 					return 0;
1638 				}
1639 				cprev = cnow;
1640 			}
1641 			/* NOTREACHED */
1642 
1643 		/*
1644 		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1645 		 * Return: write counters to the user passed counter struct
1646 		 * NB: both 1->0 and 0->1 transitions are counted except for
1647 		 *     RI where only 0->1 is counted.
1648 		 */
1649 		case TIOCGICOUNT:
1650 			cli();
1651 			cnow = info->icount;
1652 			sti();
1653 			p_cuser = (struct serial_icounter_struct *) arg;
1654 			if (put_user(cnow.cts, &p_cuser->cts) ||
1655 			    put_user(cnow.dsr, &p_cuser->dsr) ||
1656 			    put_user(cnow.rng, &p_cuser->rng) ||
1657 			    put_user(cnow.dcd, &p_cuser->dcd))
1658 				return -EFAULT;
1659 			return 0;
1660 
1661 		default:
1662 			return -ENOIOCTLCMD;
1663 		}
1664 	/* return 0; */ /* Trigger warnings if fall through by a chance. */
1665 }
1666 
1667 static void
su_set_termios(struct tty_struct * tty,struct termios * old_termios)1668 su_set_termios(struct tty_struct *tty, struct termios *old_termios)
1669 {
1670 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1671 	unsigned long flags;
1672 
1673 	if (   (tty->termios->c_cflag == old_termios->c_cflag)
1674 	    && (   RELEVANT_IFLAG(tty->termios->c_iflag)
1675 		== RELEVANT_IFLAG(old_termios->c_iflag)))
1676 	  return;
1677 
1678 	change_speed(info, old_termios);
1679 
1680 	/* Handle transition to B0 status */
1681 	if ((old_termios->c_cflag & CBAUD) &&
1682 	    !(tty->termios->c_cflag & CBAUD)) {
1683 		info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
1684 		save_flags(flags); cli();
1685 		serial_out(info, UART_MCR, info->MCR);
1686 		restore_flags(flags);
1687 	}
1688 
1689 	/* Handle transition away from B0 status */
1690 	if (!(old_termios->c_cflag & CBAUD) &&
1691 	    (tty->termios->c_cflag & CBAUD)) {
1692 		info->MCR |= UART_MCR_DTR;
1693 		if (!(tty->termios->c_cflag & CRTSCTS) ||
1694 		    !test_bit(TTY_THROTTLED, &tty->flags)) {
1695 			info->MCR |= UART_MCR_RTS;
1696 		}
1697 		save_flags(flags); cli();
1698 		serial_out(info, UART_MCR, info->MCR);
1699 		restore_flags(flags);
1700 	}
1701 
1702 	/* Handle turning off CRTSCTS */
1703 	if ((old_termios->c_cflag & CRTSCTS) &&
1704 	    !(tty->termios->c_cflag & CRTSCTS)) {
1705 		tty->hw_stopped = 0;
1706 		su_start(tty);
1707 	}
1708 
1709 #if 0
1710 	/*
1711 	 * No need to wake up processes in open wait, since they
1712 	 * sample the CLOCAL flag once, and don't recheck it.
1713 	 * XXX  It's not clear whether the current behavior is correct
1714 	 * or not.  Hence, this may change.....
1715 	 */
1716 	if (!(old_termios->c_cflag & CLOCAL) &&
1717 	    (tty->termios->c_cflag & CLOCAL))
1718 		wake_up_interruptible(&info->open_wait);
1719 #endif
1720 }
1721 
1722 /*
1723  * ------------------------------------------------------------
1724  * su_close()
1725  *
1726  * This routine is called when the serial port gets closed.  First, we
1727  * wait for the last remaining data to be sent.  Then, we unlink its
1728  * async structure from the interrupt chain if necessary, and we free
1729  * that IRQ if nothing is left in the chain.
1730  * ------------------------------------------------------------
1731  */
1732 static void
su_close(struct tty_struct * tty,struct file * filp)1733 su_close(struct tty_struct *tty, struct file * filp)
1734 {
1735 	struct su_struct *info = (struct su_struct *)tty->driver_data;
1736 	unsigned long flags;
1737 
1738 	if (!info || serial_paranoia_check(info, tty->device, "su_close"))
1739 		return;
1740 
1741 	save_flags(flags); cli();
1742 
1743 	if (tty_hung_up_p(filp)) {
1744 		DBG_CNT("before DEC-hung");
1745 		MOD_DEC_USE_COUNT;
1746 		restore_flags(flags);
1747 		return;
1748 	}
1749 
1750 #ifdef SERIAL_DEBUG_OPEN
1751 	printk("su_close ttys%d, count = %d\n", info->line, info->count);
1752 #endif
1753 	if ((tty->count == 1) && (info->count != 1)) {
1754 		/*
1755 		 * Uh, oh.  tty->count is 1, which means that the tty
1756 		 * structure will be freed.  info->count should always
1757 		 * be one in these conditions.  If it's greater than
1758 		 * one, we've got real problems, since it means the
1759 		 * serial port won't be shutdown.
1760 		 */
1761 		printk("su_close: bad serial port count; tty->count is 1, "
1762 		       "info->count is %d\n", info->count);
1763 		info->count = 1;
1764 	}
1765 	if (--info->count < 0) {
1766 		printk("su_close: bad serial port count for ttys%d: %d\n",
1767 		       info->line, info->count);
1768 		info->count = 0;
1769 	}
1770 	if (info->count) {
1771 		DBG_CNT("before DEC-2");
1772 		MOD_DEC_USE_COUNT;
1773 		restore_flags(flags);
1774 		return;
1775 	}
1776 	info->flags |= ASYNC_CLOSING;
1777 	/*
1778 	 * Save the termios structure, since this port may have
1779 	 * separate termios for callout and dialin.
1780 	 */
1781 	if (info->flags & ASYNC_NORMAL_ACTIVE)
1782 		info->normal_termios = *tty->termios;
1783 	if (info->flags & ASYNC_CALLOUT_ACTIVE)
1784 		info->callout_termios = *tty->termios;
1785 	/*
1786 	 * Now we wait for the transmit buffer to clear; and we notify
1787 	 * the line discipline to only process XON/XOFF characters.
1788 	 */
1789 	tty->closing = 1;
1790 	if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1791 		tty_wait_until_sent(tty, info->closing_wait);
1792 	/*
1793 	 * At this point we stop accepting input.  To do this, we
1794 	 * disable the receive line status interrupts, and tell the
1795 	 * interrupt driver to stop checking the data ready bit in the
1796 	 * line status register.
1797 	 */
1798 	info->IER &= ~UART_IER_RLSI;
1799 	info->read_status_mask &= ~UART_LSR_DR;
1800 	if (info->flags & ASYNC_INITIALIZED) {
1801 		serial_out(info, UART_IER, info->IER);
1802 		/*
1803 		 * Before we drop DTR, make sure the UART transmitter
1804 		 * has completely drained; this is especially
1805 		 * important if there is a transmit FIFO!
1806 		 */
1807 		su_wait_until_sent(tty, info->timeout);
1808 	}
1809 	shutdown(info);
1810 	if (tty->driver.flush_buffer)
1811 		tty->driver.flush_buffer(tty);
1812 	tty_ldisc_flush(tty);
1813 	tty->closing = 0;
1814 	info->event = 0;
1815 	info->tty = 0;
1816 	if (info->blocked_open) {
1817 		if (info->close_delay) {
1818 			current->state = TASK_INTERRUPTIBLE;
1819 			schedule_timeout(info->close_delay);
1820 		}
1821 		wake_up_interruptible(&info->open_wait);
1822 	}
1823 	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
1824 			 ASYNC_CLOSING);
1825 	wake_up_interruptible(&info->close_wait);
1826 	MOD_DEC_USE_COUNT;
1827 	restore_flags(flags);
1828 }
1829 
1830 /*
1831  * su_wait_until_sent() --- wait until the transmitter is empty
1832  */
1833 static void
su_wait_until_sent(struct tty_struct * tty,int timeout)1834 su_wait_until_sent(struct tty_struct *tty, int timeout)
1835 {
1836 	struct su_struct * info = (struct su_struct *)tty->driver_data;
1837 	unsigned long orig_jiffies, char_time;
1838 	int lsr;
1839 
1840 	if (serial_paranoia_check(info, tty->device, "su_wait_until_sent"))
1841 		return;
1842 
1843 	if (info->type == PORT_UNKNOWN)
1844 		return;
1845 
1846 	if (info->xmit_fifo_size == 0)
1847 		return; /* Just in case ... */
1848 
1849 	orig_jiffies = jiffies;
1850 	/*
1851 	 * Set the check interval to be 1/5 of the estimated time to
1852 	 * send a single character, and make it at least 1.  The check
1853 	 * interval should also be less than the timeout.
1854 	 *
1855 	 * Note: we have to use pretty tight timings here to satisfy
1856 	 * the NIST-PCTS.
1857 	 */
1858 	char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1859 	char_time = char_time / 5;
1860 	if (char_time == 0)
1861 		char_time = 1;
1862 	if (timeout)
1863 	  char_time = MIN(char_time, timeout);
1864 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1865 	printk("In su_wait_until_sent(%d) check=%lu...", timeout, char_time);
1866 	printk("jiff=%lu...", jiffies);
1867 #endif
1868 	while (!((lsr = serial_inp(info, UART_LSR)) & UART_LSR_TEMT)) {
1869 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1870 		printk("lsr = %d (jiff=%lu)...", lsr, jiffies);
1871 #endif
1872 		current->state = TASK_INTERRUPTIBLE;
1873 		schedule_timeout(char_time);
1874 		if (signal_pending(current))
1875 			break;
1876 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
1877 			break;
1878 	}
1879 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1880 	printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1881 #endif
1882 }
1883 
1884 /*
1885  * su_hangup() --- called by tty_hangup() when a hangup is signaled.
1886  */
1887 static void
su_hangup(struct tty_struct * tty)1888 su_hangup(struct tty_struct *tty)
1889 {
1890 	struct su_struct * info = (struct su_struct *)tty->driver_data;
1891 
1892 	if (serial_paranoia_check(info, tty->device, "su_hangup"))
1893 		return;
1894 
1895 	su_flush_buffer(tty);
1896 	shutdown(info);
1897 	info->event = 0;
1898 	info->count = 0;
1899 	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
1900 	info->tty = 0;
1901 	wake_up_interruptible(&info->open_wait);
1902 }
1903 
1904 /*
1905  * ------------------------------------------------------------
1906  * su_open() and friends
1907  * ------------------------------------------------------------
1908  */
1909 static int
block_til_ready(struct tty_struct * tty,struct file * filp,struct su_struct * info)1910 block_til_ready(struct tty_struct *tty, struct file * filp,
1911 		struct su_struct *info)
1912 {
1913 	DECLARE_WAITQUEUE(wait, current);
1914 	int		  retval;
1915 	int		  do_clocal = 0, extra_count = 0;
1916 	unsigned long	  flags;
1917 
1918 	/*
1919 	 * If the device is in the middle of being closed, then block
1920 	 * until it's done, and then try again.
1921 	 */
1922 	if (tty_hung_up_p(filp) ||
1923 	    (info->flags & ASYNC_CLOSING)) {
1924 		if (info->flags & ASYNC_CLOSING)
1925 			interruptible_sleep_on(&info->close_wait);
1926 #ifdef SERIAL_DO_RESTART
1927 		return ((info->flags & ASYNC_HUP_NOTIFY) ?
1928 			-EAGAIN : -ERESTARTSYS);
1929 #else
1930 		return -EAGAIN;
1931 #endif
1932 	}
1933 
1934 	/*
1935 	 * If this is a callout device, then just make sure the normal
1936 	 * device isn't being used.
1937 	 */
1938 	if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
1939 		if (info->flags & ASYNC_NORMAL_ACTIVE)
1940 			return -EBUSY;
1941 		if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
1942 		    (info->flags & ASYNC_SESSION_LOCKOUT) &&
1943 		    (info->session != current->session))
1944 		    return -EBUSY;
1945 		if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
1946 		    (info->flags & ASYNC_PGRP_LOCKOUT) &&
1947 		    (info->pgrp != current->pgrp))
1948 		    return -EBUSY;
1949 		info->flags |= ASYNC_CALLOUT_ACTIVE;
1950 		return 0;
1951 	}
1952 
1953 	/*
1954 	 * If non-blocking mode is set, or the port is not enabled,
1955 	 * then make the check up front and then exit.
1956 	 */
1957 	if ((filp->f_flags & O_NONBLOCK) ||
1958 	    (tty->flags & (1 << TTY_IO_ERROR))) {
1959 		if (info->flags & ASYNC_CALLOUT_ACTIVE)
1960 			return -EBUSY;
1961 		info->flags |= ASYNC_NORMAL_ACTIVE;
1962 		return 0;
1963 	}
1964 
1965 	if (info->flags & ASYNC_CALLOUT_ACTIVE) {
1966 		if (info->normal_termios.c_cflag & CLOCAL)
1967 			do_clocal = 1;
1968 	} else {
1969 		if (tty->termios->c_cflag & CLOCAL)
1970 			do_clocal = 1;
1971 	}
1972 
1973 	/*
1974 	 * Block waiting for the carrier detect and the line to become
1975 	 * free (i.e., not in use by the callout).  While we are in
1976 	 * this loop, info->count is dropped by one, so that
1977 	 * su_close() knows when to free things.  We restore it upon
1978 	 * exit, either normal or abnormal.
1979 	 */
1980 	retval = 0;
1981 	add_wait_queue(&info->open_wait, &wait);
1982 #ifdef SERIAL_DEBUG_OPEN
1983 	printk("block_til_ready before block: ttys%d, count = %d\n",
1984 	       info->line, info->count);
1985 #endif
1986 	save_flags(flags); cli();
1987 	if (!tty_hung_up_p(filp)) {
1988 		extra_count = 1;
1989 		info->count--;
1990 	}
1991 	restore_flags(flags);
1992 	info->blocked_open++;
1993 	while (1) {
1994 		save_flags(flags); cli();
1995 		if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
1996 		    (tty->termios->c_cflag & CBAUD))
1997 			serial_out(info, UART_MCR,
1998 				   serial_inp(info, UART_MCR) |
1999 				   (UART_MCR_DTR | UART_MCR_RTS));
2000 		restore_flags(flags);
2001 		set_current_state(TASK_INTERRUPTIBLE);
2002 		if (tty_hung_up_p(filp) ||
2003 		    !(info->flags & ASYNC_INITIALIZED)) {
2004 #ifdef SERIAL_DO_RESTART
2005 			if (info->flags & ASYNC_HUP_NOTIFY)
2006 				retval = -EAGAIN;
2007 			else
2008 				retval = -ERESTARTSYS;
2009 #else
2010 			retval = -EAGAIN;
2011 #endif
2012 			break;
2013 		}
2014 		if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
2015 		    !(info->flags & ASYNC_CLOSING) &&
2016 		    (do_clocal || (serial_in(info, UART_MSR) &
2017 				   UART_MSR_DCD)))
2018 			break;
2019 		if (signal_pending(current)) {
2020 			retval = -ERESTARTSYS;
2021 			break;
2022 		}
2023 #ifdef SERIAL_DEBUG_OPEN
2024 		printk("block_til_ready blocking: ttys%d, count = %d\n",
2025 		       info->line, info->count);
2026 #endif
2027 		schedule();
2028 	}
2029 	current->state = TASK_RUNNING;
2030 	remove_wait_queue(&info->open_wait, &wait);
2031 	if (extra_count)
2032 		info->count++;
2033 	info->blocked_open--;
2034 #ifdef SERIAL_DEBUG_OPEN
2035 	printk("block_til_ready after blocking: ttys%d, count = %d\n",
2036 	       info->line, info->count);
2037 #endif
2038 	if (retval)
2039 		return retval;
2040 	info->flags |= ASYNC_NORMAL_ACTIVE;
2041 	return 0;
2042 }
2043 
2044 /*
2045  * This routine is called whenever a serial port is opened.  It
2046  * enables interrupts for a serial port, linking in its async structure into
2047  * the IRQ chain.   It also performs the serial-specific
2048  * initialization for the tty structure.
2049  */
2050 static int
su_open(struct tty_struct * tty,struct file * filp)2051 su_open(struct tty_struct *tty, struct file * filp)
2052 {
2053 	struct su_struct	*info;
2054 	int 			retval, line;
2055 	unsigned long		page;
2056 
2057 	line = MINOR(tty->device) - tty->driver.minor_start;
2058 	if ((line < 0) || (line >= NR_PORTS))
2059 		return -ENODEV;
2060 	info = su_table + line;
2061 	info->count++;
2062 	tty->driver_data = info;
2063 	info->tty = tty;
2064 
2065 	if (serial_paranoia_check(info, tty->device, "su_open")) {
2066 		info->count--;
2067 		return -ENODEV;
2068 	}
2069 
2070 #ifdef SERIAL_DEBUG_OPEN
2071 	printk("su_open %s%d, count = %d\n", tty->driver.name, info->line,
2072 	       info->count);
2073 #endif
2074 	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
2075 
2076 	if (!tmp_buf) {
2077 		page = get_free_page(GFP_KERNEL);
2078 		if (!page)
2079 			return -ENOMEM;
2080 		if (tmp_buf)
2081 			free_page(page);
2082 		else
2083 			tmp_buf = (unsigned char *) page;
2084 	}
2085 
2086 	/*
2087 	 * If the port is the middle of closing, bail out now
2088 	 */
2089 	if (tty_hung_up_p(filp) ||
2090 	    (info->flags & ASYNC_CLOSING)) {
2091 		if (info->flags & ASYNC_CLOSING)
2092 			interruptible_sleep_on(&info->close_wait);
2093 #ifdef SERIAL_DO_RESTART
2094 		return ((info->flags & ASYNC_HUP_NOTIFY) ?
2095 			-EAGAIN : -ERESTARTSYS);
2096 #else
2097 		return -EAGAIN;
2098 #endif
2099 	}
2100 
2101 	/*
2102 	 * Start up serial port
2103 	 */
2104 	retval = startup(info);
2105 	if (retval)
2106 		return retval;
2107 
2108 	MOD_INC_USE_COUNT;
2109 	retval = block_til_ready(tty, filp, info);
2110 	if (retval) {
2111 #ifdef SERIAL_DEBUG_OPEN
2112 		printk("su_open returning after block_til_ready with %d\n",
2113 		       retval);
2114 #endif
2115 		return retval;
2116 	}
2117 
2118 	if ((info->count == 1) &&
2119 	    (info->flags & ASYNC_SPLIT_TERMIOS)) {
2120 		if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
2121 			*tty->termios = info->normal_termios;
2122 		else
2123 			*tty->termios = info->callout_termios;
2124 		change_speed(info, 0);
2125 	}
2126 #ifdef CONFIG_SERIAL_CONSOLE
2127 	if (sercons.cflag && sercons.index == line) {
2128 		tty->termios->c_cflag = sercons.cflag;
2129 		sercons.cflag = 0;
2130 		change_speed(info, 0);
2131 	}
2132 #endif
2133 	info->session = current->session;
2134 	info->pgrp = current->pgrp;
2135 
2136 #ifdef SERIAL_DEBUG_OPEN
2137 	printk("su_open ttys%d successful...", info->line);
2138 #endif
2139 	return 0;
2140 }
2141 
2142 /*
2143  * /proc fs routines....
2144  */
2145 static int
line_info(char * buf,struct su_struct * info)2146 line_info(char *buf, struct su_struct *info)
2147 {
2148 	char		stat_buf[30], control, status;
2149 	int		ret;
2150 	unsigned long	flags;
2151 
2152 	if (info->port == 0 || info->type == PORT_UNKNOWN)
2153 		return 0;
2154 
2155 	ret = sprintf(buf, "%u: uart:%s port:%lX irq:%s",
2156 		      info->line, uart_config[info->type].name,
2157 		      (unsigned long)info->port, __irq_itoa(info->irq));
2158 
2159 	/*
2160 	 * Figure out the current RS-232 lines
2161 	 */
2162 	save_flags(flags); cli();
2163 	status = serial_in(info, UART_MSR);
2164 	control = info ? info->MCR : serial_in(info, UART_MCR);
2165 	restore_flags(flags);
2166 
2167 	stat_buf[0] = 0;
2168 	stat_buf[1] = 0;
2169 	if (control & UART_MCR_RTS)
2170 		strcat(stat_buf, "|RTS");
2171 	if (status & UART_MSR_CTS)
2172 		strcat(stat_buf, "|CTS");
2173 	if (control & UART_MCR_DTR)
2174 		strcat(stat_buf, "|DTR");
2175 	if (status & UART_MSR_DSR)
2176 		strcat(stat_buf, "|DSR");
2177 	if (status & UART_MSR_DCD)
2178 		strcat(stat_buf, "|CD");
2179 	if (status & UART_MSR_RI)
2180 		strcat(stat_buf, "|RI");
2181 
2182 	if (info->quot) {
2183 		ret += sprintf(buf+ret, " baud:%u",
2184 			       info->baud_base / info->quot);
2185 	}
2186 
2187 	ret += sprintf(buf+ret, " tx:%u rx:%u",
2188 		       info->icount.tx, info->icount.rx);
2189 
2190 	if (info->icount.frame)
2191 		ret += sprintf(buf+ret, " fe:%u", info->icount.frame);
2192 
2193 	if (info->icount.parity)
2194 		ret += sprintf(buf+ret, " pe:%u", info->icount.parity);
2195 
2196 	if (info->icount.brk)
2197 		ret += sprintf(buf+ret, " brk:%u", info->icount.brk);
2198 
2199 	if (info->icount.overrun)
2200 		ret += sprintf(buf+ret, " oe:%u", info->icount.overrun);
2201 
2202 	/*
2203 	 * Last thing is the RS-232 status lines
2204 	 */
2205 	ret += sprintf(buf+ret, " %s\n", stat_buf+1);
2206 	return ret;
2207 }
2208 
su_read_proc(char * page,char ** start,off_t off,int count,int * eof,void * data)2209 int su_read_proc(char *page, char **start, off_t off, int count,
2210 		 int *eof, void *data)
2211 {
2212 	int i, len = 0;
2213 	off_t	begin = 0;
2214 
2215 	len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
2216 	for (i = 0; i < NR_PORTS && len < 4000; i++) {
2217 		len += line_info(page + len, &su_table[i]);
2218 		if (len+begin > off+count)
2219 			goto done;
2220 		if (len+begin < off) {
2221 			begin += len;
2222 			len = 0;
2223 		}
2224 	}
2225 	*eof = 1;
2226 done:
2227 	if (off >= len+begin)
2228 		return 0;
2229 	*start = page + (off-begin);
2230 	return ((count < begin+len-off) ? count : begin+len-off);
2231 }
2232 
2233 /*
2234  * ---------------------------------------------------------------------
2235  * su_XXX_init() and friends
2236  *
2237  * su_XXX_init() is called at boot-time to initialize the serial driver.
2238  * ---------------------------------------------------------------------
2239  */
2240 
2241 /*
2242  * This routine prints out the appropriate serial driver version
2243  * number, and identifies which options were configured into this
2244  * driver.
2245  */
show_su_version(void)2246 static __inline__ void __init show_su_version(void)
2247 {
2248 	char *revision = "$Revision: 1.54 $";
2249 	char *version, *p;
2250 
2251 	version = strchr(revision, ' ');
2252 	strcpy(serial_version, ++version);
2253 	p = strchr(serial_version, ' ');
2254 	*p = '\0';
2255  	printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
2256 }
2257 
2258 /*
2259  * This routine is called by su_{serial|kbd_ms}_init() to initialize a specific
2260  * serial port.  It determines what type of UART chip this serial port is
2261  * using: 8250, 16450, 16550, 16550A.  The important question is
2262  * whether or not this UART is a 16550A, since this will determine
2263  * whether or not we can use its FIFO features.
2264  */
2265 static void
autoconfig(struct su_struct * info)2266 autoconfig(struct su_struct *info)
2267 {
2268 	unsigned char status1, status2, scratch, scratch2;
2269 	struct linux_ebus_device *dev = 0;
2270 	struct linux_ebus *ebus;
2271 #ifdef CONFIG_SPARC64
2272 	struct isa_bridge *isa_br;
2273 	struct isa_device *isa_dev;
2274 #endif
2275 #ifndef __sparc_v9__
2276 	struct linux_prom_registers reg0;
2277 #endif
2278 	unsigned long flags;
2279 
2280 	if (!info->port_node || !info->port_type)
2281 		return;
2282 
2283 	/*
2284 	 * First we look for Ebus-bases su's
2285 	 */
2286 	for_each_ebus(ebus) {
2287 		for_each_ebusdev(dev, ebus) {
2288 			if (dev->prom_node == info->port_node) {
2289 				info->port = dev->resource[0].start;
2290 				info->irq = dev->irqs[0];
2291 				goto ebus_done;
2292 			}
2293 		}
2294 	}
2295 
2296 #ifdef CONFIG_SPARC64
2297 	for_each_isa(isa_br) {
2298 		for_each_isadev(isa_dev, isa_br) {
2299 			if (isa_dev->prom_node == info->port_node) {
2300 				info->port = isa_dev->resource.start;
2301 				info->irq = isa_dev->irq;
2302 				goto ebus_done;
2303 			}
2304 		}
2305 	}
2306 #endif
2307 
2308 #ifdef __sparc_v9__
2309 	/*
2310 	 * Not on Ebus, bailing.
2311 	 */
2312 	return;
2313 #else
2314 	/*
2315 	 * Not on Ebus, must be OBIO.
2316 	 */
2317 	if (prom_getproperty(info->port_node, "reg",
2318 	    (char *)&reg0, sizeof(reg0)) == -1) {
2319 		prom_printf("su: no \"reg\" property\n");
2320 		return;
2321 	}
2322 	prom_apply_obio_ranges(&reg0, 1);
2323 	if (reg0.which_io != 0) {	/* Just in case... */
2324 		prom_printf("su: bus number nonzero: 0x%x:%x\n",
2325 		    reg0.which_io, reg0.phys_addr);
2326 		return;
2327 	}
2328 	if ((info->port = (unsigned long) ioremap(reg0.phys_addr,
2329 	    reg0.reg_size)) == 0) {
2330 		prom_printf("su: cannot map\n");
2331 		return;
2332 	}
2333 
2334 	/*
2335 	 * There is no intr property on MrCoffee, so hardwire it.
2336 	 */
2337 	info->irq = IRQ_4M(13);
2338 #endif
2339 
2340 ebus_done:
2341 
2342 #ifdef SERIAL_DEBUG_OPEN
2343 	printk("Found 'su' at %016lx IRQ %s\n", info->port,
2344 		__irq_itoa(info->irq));
2345 #endif
2346 
2347 	info->magic = SERIAL_MAGIC;
2348 
2349 	save_flags(flags); cli();
2350 
2351 	/*
2352 	 * Do a simple existence test first; if we fail this, there's
2353 	 * no point trying anything else.
2354 	 *
2355 	 * 0x80 is used as a nonsense port to prevent against false
2356 	 * positives due to ISA bus float.  The assumption is that
2357 	 * 0x80 is a non-existent port; which should be safe since
2358 	 * include/asm/io.h also makes this assumption.
2359 	 */
2360 	scratch = serial_inp(info, UART_IER);
2361 	serial_outp(info, UART_IER, 0);
2362 	scratch2 = serial_inp(info, UART_IER);
2363 	serial_outp(info, UART_IER, scratch);
2364 	if (scratch2) {
2365 		restore_flags(flags);
2366 		return;		/* We failed; there's nothing here */
2367 	}
2368 
2369 	scratch = serial_inp(info, UART_MCR);
2370 	serial_outp(info, UART_MCR, UART_MCR_LOOP | scratch);
2371 	serial_outp(info, UART_MCR, UART_MCR_LOOP | 0x0A);
2372 	status1 = serial_inp(info, UART_MSR) & 0xF0;
2373 	serial_outp(info, UART_MCR, scratch);
2374 	if (status1 != 0x90) {
2375 		/*
2376 		 * This code fragment used to fail, now it fixed itself.
2377 		 * We keep the printout for a case.
2378 		 */
2379 		printk("su: loopback returned status 0x%02x\n", status1);
2380 		restore_flags(flags);
2381 		return;
2382 	}
2383 
2384 	scratch2 = serial_in(info, UART_LCR);
2385 	serial_outp(info, UART_LCR, 0xBF);	/* set up for StarTech test */
2386 	serial_outp(info, UART_EFR, 0);		/* EFR is the same as FCR */
2387 	serial_outp(info, UART_LCR, 0);
2388 	serial_outp(info, UART_FCR, UART_FCR_ENABLE_FIFO);
2389 	scratch = serial_in(info, UART_IIR) >> 6;
2390 	switch (scratch) {
2391 		case 0:
2392 			info->type = PORT_16450;
2393 			break;
2394 		case 1:
2395 			info->type = PORT_UNKNOWN;
2396 			break;
2397 		case 2:
2398 			info->type = PORT_16550;
2399 			break;
2400 		case 3:
2401 			info->type = PORT_16550A;
2402 			break;
2403 	}
2404 	if (info->type == PORT_16550A) {
2405 		/* Check for Startech UART's */
2406 		serial_outp(info, UART_LCR, scratch2 | UART_LCR_DLAB);
2407 		if (serial_in(info, UART_EFR) == 0) {
2408 			info->type = PORT_16650;
2409 		} else {
2410 			serial_outp(info, UART_LCR, 0xBF);
2411 			if (serial_in(info, UART_EFR) == 0)
2412 				info->type = PORT_16650V2;
2413 		}
2414 	}
2415 	if (info->type == PORT_16550A) {
2416 		/* Check for TI 16750 */
2417 		serial_outp(info, UART_LCR, scratch2 | UART_LCR_DLAB);
2418 		serial_outp(info, UART_FCR,
2419 			    UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
2420 		scratch = serial_in(info, UART_IIR) >> 5;
2421 		if (scratch == 7) {
2422 			serial_outp(info, UART_LCR, 0);
2423 			serial_outp(info, UART_FCR, UART_FCR_ENABLE_FIFO);
2424 			scratch = serial_in(info, UART_IIR) >> 5;
2425 			if (scratch == 6)
2426 				info->type = PORT_16750;
2427 		}
2428 		serial_outp(info, UART_FCR, UART_FCR_ENABLE_FIFO);
2429 	}
2430 	serial_outp(info, UART_LCR, scratch2);
2431 	if (info->type == PORT_16450) {
2432 		scratch = serial_in(info, UART_SCR);
2433 		serial_outp(info, UART_SCR, 0xa5);
2434 		status1 = serial_in(info, UART_SCR);
2435 		serial_outp(info, UART_SCR, 0x5a);
2436 		status2 = serial_in(info, UART_SCR);
2437 		serial_outp(info, UART_SCR, scratch);
2438 
2439 		if ((status1 != 0xa5) || (status2 != 0x5a))
2440 			info->type = PORT_8250;
2441 	}
2442 	info->xmit_fifo_size = uart_config[info->type].dfl_xmit_fifo_size;
2443 
2444 	if (info->type == PORT_UNKNOWN) {
2445 		restore_flags(flags);
2446 		return;
2447 	}
2448 
2449 	sprintf(info->name, "su(%s)", su_typev[info->port_type]);
2450 
2451 	/*
2452 	 * Reset the UART.
2453 	 */
2454 	serial_outp(info, UART_MCR, 0x00);
2455 	serial_outp(info, UART_FCR, (UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT));
2456 	(void)serial_in(info, UART_RX);
2457 	serial_outp(info, UART_IER, 0x00);
2458 
2459 	restore_flags(flags);
2460 }
2461 
2462 /* This is used by the SAB driver to adjust where its minor
2463  * numbers start, we always are probed for first.
2464  */
2465 int su_num_ports = 0;
2466 EXPORT_SYMBOL(su_num_ports);
2467 
2468 /*
2469  * The serial driver boot-time initialization code!
2470  */
su_serial_init(void)2471 int __init su_serial_init(void)
2472 {
2473 	int i;
2474 	struct su_struct *info;
2475 
2476 	init_bh(SERIAL_BH, do_serial_bh);
2477 	show_su_version();
2478 
2479 	/* Initialize the tty_driver structure */
2480 
2481 	memset(&serial_driver, 0, sizeof(struct tty_driver));
2482 	serial_driver.magic = TTY_DRIVER_MAGIC;
2483 	serial_driver.driver_name = "su";
2484 #ifdef CONFIG_DEVFS_FS
2485 	serial_driver.name = "tts/%d";
2486 #else
2487 	serial_driver.name = "ttyS";
2488 #endif
2489 	serial_driver.major = TTY_MAJOR;
2490 	serial_driver.minor_start = 64;
2491 	serial_driver.num = NR_PORTS;
2492 	serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
2493 	serial_driver.subtype = SERIAL_TYPE_NORMAL;
2494 	serial_driver.init_termios = tty_std_termios;
2495 	serial_driver.init_termios.c_cflag =
2496 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
2497 	serial_driver.flags = TTY_DRIVER_REAL_RAW;
2498 	serial_driver.refcount = &serial_refcount;
2499 	serial_driver.table = serial_table;
2500 	serial_driver.termios = serial_termios;
2501 	serial_driver.termios_locked = serial_termios_locked;
2502 
2503 	serial_driver.open = su_open;
2504 	serial_driver.close = su_close;
2505 	serial_driver.write = su_write;
2506 	serial_driver.put_char = su_put_char;
2507 	serial_driver.flush_chars = su_flush_chars;
2508 	serial_driver.write_room = su_write_room;
2509 	serial_driver.chars_in_buffer = su_chars_in_buffer;
2510 	serial_driver.flush_buffer = su_flush_buffer;
2511 	serial_driver.ioctl = su_ioctl;
2512 	serial_driver.throttle = su_throttle;
2513 	serial_driver.unthrottle = su_unthrottle;
2514 	serial_driver.send_xchar = su_send_xchar;
2515 	serial_driver.set_termios = su_set_termios;
2516 	serial_driver.stop = su_stop;
2517 	serial_driver.start = su_start;
2518 	serial_driver.hangup = su_hangup;
2519 	serial_driver.break_ctl = su_break;
2520 	serial_driver.wait_until_sent = su_wait_until_sent;
2521 	serial_driver.read_proc = su_read_proc;
2522 
2523 	/*
2524 	 * The callout device is just like normal device except for
2525 	 * major number and the subtype code.
2526 	 */
2527 	callout_driver = serial_driver;
2528 #ifdef CONFIG_DEVFS_FS
2529 	callout_driver.name = "cua/%d";
2530 #else
2531 	callout_driver.name = "cua";
2532 #endif
2533 	callout_driver.major = TTYAUX_MAJOR;
2534 	callout_driver.subtype = SERIAL_TYPE_CALLOUT;
2535 	callout_driver.read_proc = 0;
2536 	callout_driver.proc_entry = 0;
2537 
2538 	if (tty_register_driver(&serial_driver))
2539 		panic("Couldn't register regular su\n");
2540 	if (tty_register_driver(&callout_driver))
2541 		panic("Couldn't register callout su\n");
2542 
2543 	for (i = 0, info = su_table; i < NR_PORTS; i++, info++) {
2544 		info->line = i;
2545 		info->type = PORT_UNKNOWN;
2546 		info->baud_base = BAUD_BASE;
2547 		/* info->flags = 0; */
2548 		info->custom_divisor = 0;
2549 		info->close_delay = 5*HZ/10;
2550 		info->closing_wait = 30*HZ;
2551 		info->callout_termios = callout_driver.init_termios;
2552 		info->normal_termios = serial_driver.init_termios;
2553 		info->icount.cts = info->icount.dsr =
2554 			info->icount.rng = info->icount.dcd = 0;
2555 		info->icount.rx = info->icount.tx = 0;
2556 		info->icount.frame = info->icount.parity = 0;
2557 		info->icount.overrun = info->icount.brk = 0;
2558 		info->tqueue.routine = do_softint;
2559 		info->tqueue.data = info;
2560 		info->cflag = serial_driver.init_termios.c_cflag;
2561 		init_waitqueue_head(&info->open_wait);
2562 		init_waitqueue_head(&info->close_wait);
2563 		init_waitqueue_head(&info->delta_msr_wait);
2564 
2565 		autoconfig(info);
2566 		if (info->type == PORT_UNKNOWN)
2567 			continue;
2568 
2569 		printk(KERN_INFO "%s at 0x%lx (tty %d irq %s) is a %s\n",
2570 		       info->name, (long)info->port, i, __irq_itoa(info->irq),
2571 		       uart_config[info->type].name);
2572 	}
2573 
2574 	for (i = 0, info = su_table; i < NR_PORTS; i++, info++)
2575 		if (info->type == PORT_UNKNOWN)
2576 			break;
2577 
2578 	su_num_ports = i;
2579 	serial_driver.num = callout_driver.num = i;
2580 
2581 	return 0;
2582 }
2583 
su_kbd_ms_init(void)2584 int __init su_kbd_ms_init(void)
2585 {
2586 	int i;
2587 	struct su_struct *info;
2588 
2589 	show_su_version();
2590 
2591 	for (i = 0, info = su_table; i < 2; i++, info++) {
2592 		info->line = i;
2593 		info->type = PORT_UNKNOWN;
2594 		info->baud_base = BAUD_BASE;
2595 
2596 		if (info->port_type == SU_PORT_KBD)
2597 			info->cflag = B1200 | CS8 | CLOCAL | CREAD;
2598 		else
2599 			info->cflag = B4800 | CS8 | CLOCAL | CREAD;
2600 
2601 		init_waitqueue_head(&info->open_wait);
2602 		init_waitqueue_head(&info->close_wait);
2603 		init_waitqueue_head(&info->delta_msr_wait);
2604 
2605 		autoconfig(info);
2606 		if (info->type == PORT_UNKNOWN)
2607 			continue;
2608 
2609 		printk(KERN_INFO "%s at 0x%lx (irq = %s) is a %s\n",
2610 		       info->name, info->port, __irq_itoa(info->irq),
2611 		       uart_config[info->type].name);
2612 
2613 		startup(info);
2614 		if (info->port_type == SU_PORT_KBD)
2615 			keyboard_zsinit(su_put_char_kbd);
2616 		else
2617 			sun_mouse_zsinit();
2618 	}
2619 	return 0;
2620 }
2621 
su_node_ok(int node,char * name,int namelen)2622 static int su_node_ok(int node, char *name, int namelen)
2623 {
2624 	if (strncmp(name, "su", namelen) == 0 ||
2625 	    strncmp(name, "su_pnp", namelen) == 0)
2626 		return 1;
2627 
2628 	if (strncmp(name, "serial", namelen) == 0) {
2629 		char compat[32];
2630 		int clen;
2631 
2632 		/* Is it _really_ a 'su' device? */
2633 		clen = prom_getproperty(node, "compatible", compat, sizeof(compat));
2634 		if (clen > 0) {
2635 			if (strncmp(compat, "sab82532", 8) == 0) {
2636 				/* Nope, Siemens serial, not for us. */
2637 				return 0;
2638 			}
2639 		}
2640 		return 1;
2641 	}
2642 
2643 	return 0;
2644 }
2645 
2646 /*
2647  * We got several platforms which present 'su' in different parts
2648  * of device tree. 'su' may be found under obio, ebus, isa and pci.
2649  * We walk over the tree and find them wherever PROM hides them.
2650  */
su_probe_any(struct su_probe_scan * t,int sunode)2651 void __init su_probe_any(struct su_probe_scan *t, int sunode)
2652 {
2653 	struct su_struct *info;
2654 	int len;
2655 
2656 	if (t->devices >= NR_PORTS) return;
2657 
2658 	for (; sunode != 0; sunode = prom_getsibling(sunode)) {
2659 		len = prom_getproperty(sunode, "name", t->prop, SU_PROPSIZE);
2660 		if (len <= 1) continue;		/* Broken PROM node */
2661 		if (su_node_ok(sunode, t->prop, len)) {
2662 			info = &su_table[t->devices];
2663 			if (t->kbnode != 0 && sunode == t->kbnode) {
2664 				t->kbx = t->devices;
2665 				info->port_type = SU_PORT_KBD;
2666 			} else if (t->msnode != 0 && sunode == t->msnode) {
2667 				t->msx = t->devices;
2668 				info->port_type = SU_PORT_MS;
2669 			} else {
2670 #ifdef __sparc_v9__
2671 				/*
2672 				 * Do not attempt to use the truncated
2673 				 * keyboard/mouse ports as serial ports
2674 				 * on Ultras with PC keyboard attached.
2675 				 */
2676 				if (prom_getbool(sunode, "mouse"))
2677 					continue;
2678 				if (prom_getbool(sunode, "keyboard"))
2679 					continue;
2680 #endif
2681 				info->port_type = SU_PORT_PORT;
2682 			}
2683 			info->is_console = 0;
2684 			info->port_node = sunode;
2685 			++t->devices;
2686 		} else {
2687 			su_probe_any(t, prom_getchild(sunode));
2688 		}
2689 	}
2690 }
2691 
su_probe(void)2692 int __init su_probe(void)
2693 {
2694 	int node;
2695 	int len;
2696 	struct su_probe_scan scan;
2697 
2698 	/*
2699 	 * First, we scan the tree.
2700 	 */
2701 	scan.devices = 0;
2702 	scan.msx = -1;
2703 	scan.kbx = -1;
2704 	scan.kbnode = 0;
2705 	scan.msnode = 0;
2706 
2707 	/*
2708 	 * Get the nodes for keyboard and mouse from 'aliases'...
2709 	 */
2710         node = prom_getchild(prom_root_node);
2711 	node = prom_searchsiblings(node, "aliases");
2712 	if (node != 0) {
2713 
2714 		len = prom_getproperty(node, "keyboard", scan.prop,SU_PROPSIZE);
2715 		if (len > 0) {
2716 			scan.prop[len] = 0;
2717 			scan.kbnode = prom_finddevice(scan.prop);
2718 		}
2719 
2720 		len = prom_getproperty(node, "mouse", scan.prop, SU_PROPSIZE);
2721 		if (len > 0) {
2722 			scan.prop[len] = 0;
2723 			scan.msnode = prom_finddevice(scan.prop);
2724 		}
2725 	}
2726 
2727 	su_probe_any(&scan, prom_getchild(prom_root_node));
2728 
2729 	/*
2730 	 * Second, we process the special case of keyboard and mouse.
2731 	 *
2732 	 * Currently if we got keyboard and mouse hooked to "su" ports
2733 	 * we do not use any possible remaining "su" as a serial port.
2734 	 * Thus, we ignore values of .msx and .kbx, then compact ports.
2735 	 * Those who want to address this issue need to merge
2736 	 * su_serial_init() and su_ms_kbd_init().
2737 	 */
2738 	if (scan.msx != -1 && scan.kbx != -1) {
2739 		su_table[0].port_type = SU_PORT_MS;
2740 		su_table[0].is_console = 0;
2741 		su_table[0].port_node = scan.msnode;
2742 		su_table[1].port_type = SU_PORT_KBD;
2743 		su_table[1].is_console = 0;
2744 		su_table[1].port_node = scan.kbnode;
2745 
2746         	sunserial_setinitfunc(su_kbd_ms_init);
2747         	rs_ops.rs_change_mouse_baud = su_change_mouse_baud;
2748 		sunkbd_setinitfunc(sun_kbd_init);
2749 		kbd_ops.compute_shiftstate = sun_compute_shiftstate;
2750 		kbd_ops.setledstate = sun_setledstate;
2751 		kbd_ops.getledstate = sun_getledstate;
2752 		kbd_ops.setkeycode = sun_setkeycode;
2753 		kbd_ops.getkeycode = sun_getkeycode;
2754 #ifdef CONFIG_PCI
2755 		sunkbd_install_keymaps(sun_key_maps,
2756 		    sun_keymap_count, sun_func_buf, sun_func_table,
2757 		    sun_funcbufsize, sun_funcbufleft,
2758 		    sun_accent_table, sun_accent_table_size);
2759 #endif
2760 		return 0;
2761 	}
2762 	if (scan.msx != -1 || scan.kbx != -1) {
2763 		printk("su_probe: cannot match keyboard and mouse, confused\n");
2764 		return -ENODEV;
2765 	}
2766 
2767 	if (scan.devices == 0)
2768 		return -ENODEV;
2769 
2770 #ifdef CONFIG_SERIAL_CONSOLE
2771 	/*
2772 	 * Console must be initiated after the generic initialization.
2773 	 * sunserial_setinitfunc inverts order, so call this before next one.
2774 	 */
2775 	sunserial_setinitfunc(su_serial_console_init);
2776 #endif
2777        	sunserial_setinitfunc(su_serial_init);
2778 	return 0;
2779 }
2780 
2781 /*
2782  * ------------------------------------------------------------
2783  * Serial console driver
2784  * ------------------------------------------------------------
2785  */
2786 #ifdef CONFIG_SERIAL_CONSOLE
2787 
2788 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
2789 
2790 /*
2791  *	Wait for transmitter & holding register to empty
2792  */
2793 static __inline__ void
wait_for_xmitr(struct su_struct * info)2794 wait_for_xmitr(struct su_struct *info)
2795 {
2796 	int lsr;
2797 	unsigned int tmout = 1000000;
2798 
2799 	do {
2800 		lsr = su_inb(info, UART_LSR);
2801 		if (--tmout == 0)
2802 			break;
2803 	} while ((lsr & BOTH_EMPTY) != BOTH_EMPTY);
2804 }
2805 
2806 /*
2807  *	Print a string to the serial port trying not to disturb
2808  *	any possible real use of the port...
2809  */
2810 static void
serial_console_write(struct console * co,const char * s,unsigned count)2811 serial_console_write(struct console *co, const char *s,
2812 				unsigned count)
2813 {
2814 	struct su_struct *info;
2815 	int ier;
2816 	unsigned i;
2817 
2818 	info = su_table + co->index;
2819 	/*
2820 	 *	First save the IER then disable the interrupts
2821 	 */
2822 	ier = su_inb(info, UART_IER);
2823 	su_outb(info, UART_IER, 0x00);
2824 
2825 	/*
2826 	 *	Now, do each character
2827 	 */
2828 	for (i = 0; i < count; i++, s++) {
2829 		wait_for_xmitr(info);
2830 
2831 		/*
2832 		 *	Send the character out.
2833 		 *	If a LF, also do CR...
2834 		 */
2835 		su_outb(info, UART_TX, *s);
2836 		if (*s == 10) {
2837 			wait_for_xmitr(info);
2838 			su_outb(info, UART_TX, 13);
2839 		}
2840 	}
2841 
2842 	/*
2843 	 *	Finally, Wait for transmitter & holding register to empty
2844 	 * 	and restore the IER
2845 	 */
2846 	wait_for_xmitr(info);
2847 	su_outb(info, UART_IER, ier);
2848 }
2849 
2850 static kdev_t
serial_console_device(struct console * c)2851 serial_console_device(struct console *c)
2852 {
2853 	return MKDEV(TTY_MAJOR, 64 + c->index);
2854 }
2855 
2856 /*
2857  *	Setup initial baud/bits/parity. We do two things here:
2858  *	- construct a cflag setting for the first su_open()
2859  *	- initialize the serial port
2860  *	Return non-zero if we didn't find a serial port.
2861  */
serial_console_setup(struct console * co,char * options)2862 static int __init serial_console_setup(struct console *co, char *options)
2863 {
2864 	struct su_struct *info;
2865 	unsigned cval;
2866 	int	baud = 9600;
2867 	int	bits = 8;
2868 	int	parity = 'n';
2869 	int	cflag = CREAD | HUPCL | CLOCAL;
2870 	int	quot = 0;
2871 	char	*s;
2872 
2873 	if (options) {
2874 		baud = simple_strtoul(options, NULL, 10);
2875 		s = options;
2876 		while (*s >= '0' && *s <= '9')
2877 			s++;
2878 		if (*s) parity = *s++;
2879 		if (*s) bits   = *s - '0';
2880 	}
2881 
2882 	/*
2883 	 *	Now construct a cflag setting.
2884 	 */
2885 	switch (baud) {
2886 		case 1200:
2887 			cflag |= B1200;
2888 			break;
2889 		case 2400:
2890 			cflag |= B2400;
2891 			break;
2892 		case 4800:
2893 			cflag |= B4800;
2894 			break;
2895 		case 19200:
2896 			cflag |= B19200;
2897 			break;
2898 		case 38400:
2899 			cflag |= B38400;
2900 			break;
2901 		case 57600:
2902 			cflag |= B57600;
2903 			break;
2904 		case 115200:
2905 			cflag |= B115200;
2906 			break;
2907 		case 9600:
2908 		default:
2909 			cflag |= B9600;
2910 			baud = 9600;
2911 			break;
2912 	}
2913 	switch (bits) {
2914 		case 7:
2915 			cflag |= CS7;
2916 			break;
2917 		default:
2918 		case 8:
2919 			cflag |= CS8;
2920 			break;
2921 	}
2922 	switch (parity) {
2923 		case 'o': case 'O':
2924 			cflag |= PARODD;
2925 			break;
2926 		case 'e': case 'E':
2927 			cflag |= PARENB;
2928 			break;
2929 	}
2930 	co->cflag = cflag;
2931 
2932 	/*
2933 	 *	Divisor, bytesize and parity
2934 	 */
2935 	info = su_table + co->index;
2936 	quot = BAUD_BASE / baud;
2937 	cval = cflag & (CSIZE | CSTOPB);
2938 #if defined(__powerpc__) || defined(__alpha__)
2939 	cval >>= 8;
2940 #else /* !__powerpc__ && !__alpha__ */
2941 	cval >>= 4;
2942 #endif /* !__powerpc__ && !__alpha__ */
2943 	if (cflag & PARENB)
2944 		cval |= UART_LCR_PARITY;
2945 	if (!(cflag & PARODD))
2946 		cval |= UART_LCR_EPAR;
2947 
2948 	/*
2949 	 *	Disable UART interrupts, set DTR and RTS high
2950 	 *	and set speed.
2951 	 */
2952 	su_outb(info, UART_IER, 0);
2953 	su_outb(info, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
2954 	su_outb(info, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
2955 	su_outb(info, UART_DLL, quot & 0xff);		/* LS of divisor */
2956 	su_outb(info, UART_DLM, quot >> 8);		/* MS of divisor */
2957 	su_outb(info, UART_LCR, cval);			/* reset DLAB */
2958 	info->quot = quot;
2959 
2960 	/*
2961 	 *	If we read 0xff from the LSR, there is no UART here.
2962 	 */
2963 	if (su_inb(info, UART_LSR) == 0xff)
2964 		return -1;
2965 
2966 	info->is_console = 1;
2967 
2968 	return 0;
2969 }
2970 
2971 static struct console sercons = {
2972 	name:		"ttyS",
2973 	write:		serial_console_write,
2974 	device:		serial_console_device,
2975 	setup:		serial_console_setup,
2976 	flags:		CON_PRINTBUFFER,
2977 	index:		-1,
2978 };
2979 
2980 int su_console_registered = 0;
2981 
2982 /*
2983  *	Register console.
2984  */
su_serial_console_init(void)2985 int __init su_serial_console_init(void)
2986 {
2987 	extern int con_is_present(void);
2988 	int index;
2989 
2990 	if (con_is_present())
2991 		return 0;
2992 	if (serial_console == 0)
2993 		return 0;
2994 	index = serial_console - 1;
2995 	if (su_table[index].port == 0 || su_table[index].port_node == 0)
2996 		return 0;
2997 	sercons.index = index;
2998 	register_console(&sercons);
2999 	su_console_registered = 1;
3000 	return 0;
3001 }
3002 
3003 #endif /* CONFIG_SERIAL_CONSOLE */
3004