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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/drivers/char/8250.c
3 *
4 * Driver for 8250/16550-type serial ports
5 *
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
7 *
8 * Copyright (C) 2001 Russell King.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * $Id: 8250.c,v 1.90 2002/07/28 10:03:27 rmk Exp $
16 *
17 * A note about mapbase / membase
18 *
19 * mapbase is the physical address of the IO port.
20 * membase is an 'ioremapped' cookie.
21 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
23#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
24#define SUPPORT_SYSRQ
25#endif
26
27#include <linux/module.h>
28#include <linux/moduleparam.h>
29#include <linux/ioport.h>
30#include <linux/init.h>
31#include <linux/console.h>
32#include <linux/sysrq.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/delay.h>
Russell Kingd052d1b2005-10-29 19:07:23 +010034#include <linux/platform_device.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include <linux/tty.h>
36#include <linux/tty_flip.h>
37#include <linux/serial_reg.h>
38#include <linux/serial_core.h>
39#include <linux/serial.h>
40#include <linux/serial_8250.h>
Andrew Morton78512ec2005-11-07 00:59:13 -080041#include <linux/nmi.h>
Arjan van de Venf392ecf2006-01-12 18:44:32 +000042#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043
44#include <asm/io.h>
45#include <asm/irq.h>
46
47#include "8250.h"
48
49/*
50 * Configuration:
Thomas Gleixner40663cc2006-07-01 19:29:43 -070051 * share_irqs - whether we pass IRQF_SHARED to request_irq(). This option
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 * is unsafe when used on edge-triggered interrupts.
53 */
Adrian Bunk408b6642005-05-01 08:59:29 -070054static unsigned int share_irqs = SERIAL8250_SHARE_IRQS;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
Dave Jonesa61c2d72006-01-07 23:18:19 +000056static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS;
57
Linus Torvalds1da177e2005-04-16 15:20:36 -070058/*
59 * Debugging.
60 */
61#if 0
62#define DEBUG_AUTOCONF(fmt...) printk(fmt)
63#else
64#define DEBUG_AUTOCONF(fmt...) do { } while (0)
65#endif
66
67#if 0
68#define DEBUG_INTR(fmt...) printk(fmt)
69#else
70#define DEBUG_INTR(fmt...) do { } while (0)
71#endif
72
73#define PASS_LIMIT 256
74
75/*
76 * We default to IRQ0 for the "no irq" hack. Some
77 * machine types want others as well - they're free
78 * to redefine this in their header file.
79 */
80#define is_real_interrupt(irq) ((irq) != 0)
81
Linus Torvalds1da177e2005-04-16 15:20:36 -070082#ifdef CONFIG_SERIAL_8250_DETECT_IRQ
83#define CONFIG_SERIAL_DETECT_IRQ 1
84#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070085#ifdef CONFIG_SERIAL_8250_MANY_PORTS
86#define CONFIG_SERIAL_MANY_PORTS 1
87#endif
88
89/*
90 * HUB6 is always on. This will be removed once the header
91 * files have been cleaned.
92 */
93#define CONFIG_HUB6 1
94
95#include <asm/serial.h>
96
97/*
98 * SERIAL_PORT_DFNS tells us about built-in ports that have no
99 * standard enumeration mechanism. Platforms that can find all
100 * serial ports via mechanisms like ACPI or PCI need not supply it.
101 */
102#ifndef SERIAL_PORT_DFNS
103#define SERIAL_PORT_DFNS
104#endif
105
Arjan van de Vencb3592b2005-11-28 21:04:11 +0000106static const struct old_serial_port old_serial_port[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 SERIAL_PORT_DFNS /* defined in asm/serial.h */
108};
109
Russell King026d02a2005-06-29 18:45:19 +0100110#define UART_NR CONFIG_SERIAL_8250_NR_UARTS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
112#ifdef CONFIG_SERIAL_8250_RSA
113
114#define PORT_RSA_MAX 4
115static unsigned long probe_rsa[PORT_RSA_MAX];
116static unsigned int probe_rsa_count;
117#endif /* CONFIG_SERIAL_8250_RSA */
118
119struct uart_8250_port {
120 struct uart_port port;
121 struct timer_list timer; /* "no irq" timer */
122 struct list_head list; /* ports on this IRQ */
Russell King4ba5e352005-06-23 10:43:04 +0100123 unsigned short capabilities; /* port capabilities */
124 unsigned short bugs; /* port bugs */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 unsigned int tx_loadsz; /* transmit fifo load size */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 unsigned char acr;
127 unsigned char ier;
128 unsigned char lcr;
129 unsigned char mcr;
130 unsigned char mcr_mask; /* mask of user bits */
131 unsigned char mcr_force; /* mask of forced bits */
Corey Minyardad4c2aa2007-08-22 14:01:18 -0700132
133 /*
134 * Some bits in registers are cleared on a read, so they must
135 * be saved whenever the register is read but the bits will not
136 * be immediately processed.
137 */
138#define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
139 unsigned char lsr_saved_flags;
140#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
141 unsigned char msr_saved_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
143 /*
144 * We provide a per-port pm hook.
145 */
146 void (*pm)(struct uart_port *port,
147 unsigned int state, unsigned int old);
148};
149
150struct irq_info {
151 spinlock_t lock;
152 struct list_head *head;
153};
154
155static struct irq_info irq_lists[NR_IRQS];
156
157/*
158 * Here we define the default xmit fifo size used for each type of UART.
159 */
160static const struct serial8250_config uart_config[] = {
161 [PORT_UNKNOWN] = {
162 .name = "unknown",
163 .fifo_size = 1,
164 .tx_loadsz = 1,
165 },
166 [PORT_8250] = {
167 .name = "8250",
168 .fifo_size = 1,
169 .tx_loadsz = 1,
170 },
171 [PORT_16450] = {
172 .name = "16450",
173 .fifo_size = 1,
174 .tx_loadsz = 1,
175 },
176 [PORT_16550] = {
177 .name = "16550",
178 .fifo_size = 1,
179 .tx_loadsz = 1,
180 },
181 [PORT_16550A] = {
182 .name = "16550A",
183 .fifo_size = 16,
184 .tx_loadsz = 16,
185 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
186 .flags = UART_CAP_FIFO,
187 },
188 [PORT_CIRRUS] = {
189 .name = "Cirrus",
190 .fifo_size = 1,
191 .tx_loadsz = 1,
192 },
193 [PORT_16650] = {
194 .name = "ST16650",
195 .fifo_size = 1,
196 .tx_loadsz = 1,
197 .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
198 },
199 [PORT_16650V2] = {
200 .name = "ST16650V2",
201 .fifo_size = 32,
202 .tx_loadsz = 16,
203 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
204 UART_FCR_T_TRIG_00,
205 .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
206 },
207 [PORT_16750] = {
208 .name = "TI16750",
209 .fifo_size = 64,
210 .tx_loadsz = 64,
211 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
212 UART_FCR7_64BYTE,
213 .flags = UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE,
214 },
215 [PORT_STARTECH] = {
216 .name = "Startech",
217 .fifo_size = 1,
218 .tx_loadsz = 1,
219 },
220 [PORT_16C950] = {
221 .name = "16C950/954",
222 .fifo_size = 128,
223 .tx_loadsz = 128,
224 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
225 .flags = UART_CAP_FIFO,
226 },
227 [PORT_16654] = {
228 .name = "ST16654",
229 .fifo_size = 64,
230 .tx_loadsz = 32,
231 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
232 UART_FCR_T_TRIG_10,
233 .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
234 },
235 [PORT_16850] = {
236 .name = "XR16850",
237 .fifo_size = 128,
238 .tx_loadsz = 128,
239 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
240 .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
241 },
242 [PORT_RSA] = {
243 .name = "RSA",
244 .fifo_size = 2048,
245 .tx_loadsz = 2048,
246 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11,
247 .flags = UART_CAP_FIFO,
248 },
249 [PORT_NS16550A] = {
250 .name = "NS16550A",
251 .fifo_size = 16,
252 .tx_loadsz = 16,
253 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
254 .flags = UART_CAP_FIFO | UART_NATSEMI,
255 },
256 [PORT_XSCALE] = {
257 .name = "XScale",
258 .fifo_size = 32,
259 .tx_loadsz = 32,
260 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
261 .flags = UART_CAP_FIFO | UART_CAP_UUE,
262 },
Thomas Koellerbd71c182007-05-06 14:48:47 -0700263 [PORT_RM9000] = {
264 .name = "RM9000",
265 .fifo_size = 16,
266 .tx_loadsz = 16,
267 .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
268 .flags = UART_CAP_FIFO,
269 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270};
271
Thomas Koellerbd71c182007-05-06 14:48:47 -0700272#if defined (CONFIG_SERIAL_8250_AU1X00)
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000273
274/* Au1x00 UART hardware has a weird register layout */
275static const u8 au_io_in_map[] = {
276 [UART_RX] = 0,
277 [UART_IER] = 2,
278 [UART_IIR] = 3,
279 [UART_LCR] = 5,
280 [UART_MCR] = 6,
281 [UART_LSR] = 7,
282 [UART_MSR] = 8,
283};
284
285static const u8 au_io_out_map[] = {
286 [UART_TX] = 1,
287 [UART_IER] = 2,
288 [UART_FCR] = 4,
289 [UART_LCR] = 5,
290 [UART_MCR] = 6,
291};
292
293/* sane hardware needs no mapping */
294static inline int map_8250_in_reg(struct uart_8250_port *up, int offset)
295{
296 if (up->port.iotype != UPIO_AU)
297 return offset;
298 return au_io_in_map[offset];
299}
300
301static inline int map_8250_out_reg(struct uart_8250_port *up, int offset)
302{
303 if (up->port.iotype != UPIO_AU)
304 return offset;
305 return au_io_out_map[offset];
306}
307
Thomas Koellerbd71c182007-05-06 14:48:47 -0700308#elif defined (CONFIG_SERIAL_8250_RM9K)
309
310static const u8
311 regmap_in[8] = {
312 [UART_RX] = 0x00,
313 [UART_IER] = 0x0c,
314 [UART_IIR] = 0x14,
315 [UART_LCR] = 0x1c,
316 [UART_MCR] = 0x20,
317 [UART_LSR] = 0x24,
318 [UART_MSR] = 0x28,
319 [UART_SCR] = 0x2c
320 },
321 regmap_out[8] = {
322 [UART_TX] = 0x04,
323 [UART_IER] = 0x0c,
324 [UART_FCR] = 0x18,
325 [UART_LCR] = 0x1c,
326 [UART_MCR] = 0x20,
327 [UART_LSR] = 0x24,
328 [UART_MSR] = 0x28,
329 [UART_SCR] = 0x2c
330 };
331
332static inline int map_8250_in_reg(struct uart_8250_port *up, int offset)
333{
334 if (up->port.iotype != UPIO_RM9000)
335 return offset;
336 return regmap_in[offset];
337}
338
339static inline int map_8250_out_reg(struct uart_8250_port *up, int offset)
340{
341 if (up->port.iotype != UPIO_RM9000)
342 return offset;
343 return regmap_out[offset];
344}
345
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000346#else
347
348/* sane hardware needs no mapping */
349#define map_8250_in_reg(up, offset) (offset)
350#define map_8250_out_reg(up, offset) (offset)
351
352#endif
353
Russell Kingea8874d2006-01-04 19:43:24 +0000354static unsigned int serial_in(struct uart_8250_port *up, int offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355{
Zang Roy-r619113be91ec2006-06-30 02:29:58 -0700356 unsigned int tmp;
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000357 offset = map_8250_in_reg(up, offset) << up->port.regshift;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
359 switch (up->port.iotype) {
360 case UPIO_HUB6:
361 outb(up->port.hub6 - 1 + offset, up->port.iobase);
362 return inb(up->port.iobase + 1);
363
364 case UPIO_MEM:
Marc St-Jeanbeab6972007-05-06 14:48:45 -0700365 case UPIO_DWAPB:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 return readb(up->port.membase + offset);
367
Thomas Koellerbd71c182007-05-06 14:48:47 -0700368 case UPIO_RM9000:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 case UPIO_MEM32:
370 return readl(up->port.membase + offset);
371
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000372#ifdef CONFIG_SERIAL_8250_AU1X00
373 case UPIO_AU:
374 return __raw_readl(up->port.membase + offset);
375#endif
376
Zang Roy-r619113be91ec2006-06-30 02:29:58 -0700377 case UPIO_TSI:
378 if (offset == UART_IIR) {
Al Viro9e84b602006-09-23 01:39:45 +0100379 tmp = readl(up->port.membase + (UART_IIR & ~3));
380 return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
Zang Roy-r619113be91ec2006-06-30 02:29:58 -0700381 } else
382 return readb(up->port.membase + offset);
383
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 default:
385 return inb(up->port.iobase + offset);
386 }
387}
388
Russell Kingea8874d2006-01-04 19:43:24 +0000389static void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390serial_out(struct uart_8250_port *up, int offset, int value)
391{
Marc St-Jeanbeab6972007-05-06 14:48:45 -0700392 /* Save the offset before it's remapped */
393 int save_offset = offset;
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000394 offset = map_8250_out_reg(up, offset) << up->port.regshift;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395
396 switch (up->port.iotype) {
397 case UPIO_HUB6:
398 outb(up->port.hub6 - 1 + offset, up->port.iobase);
399 outb(value, up->port.iobase + 1);
400 break;
401
402 case UPIO_MEM:
403 writeb(value, up->port.membase + offset);
404 break;
405
Thomas Koellerbd71c182007-05-06 14:48:47 -0700406 case UPIO_RM9000:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 case UPIO_MEM32:
408 writel(value, up->port.membase + offset);
409 break;
410
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000411#ifdef CONFIG_SERIAL_8250_AU1X00
412 case UPIO_AU:
413 __raw_writel(value, up->port.membase + offset);
414 break;
415#endif
Zang Roy-r619113be91ec2006-06-30 02:29:58 -0700416 case UPIO_TSI:
417 if (!((offset == UART_IER) && (value & UART_IER_UUE)))
418 writeb(value, up->port.membase + offset);
419 break;
Pantelis Antoniou21c614a2005-11-06 09:07:03 +0000420
Marc St-Jeanbeab6972007-05-06 14:48:45 -0700421 case UPIO_DWAPB:
422 /* Save the LCR value so it can be re-written when a
423 * Busy Detect interrupt occurs. */
424 if (save_offset == UART_LCR)
425 up->lcr = value;
426 writeb(value, up->port.membase + offset);
427 /* Read the IER to ensure any interrupt is cleared before
428 * returning from ISR. */
429 if (save_offset == UART_TX || save_offset == UART_IER)
430 value = serial_in(up, UART_IER);
431 break;
432
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 default:
434 outb(value, up->port.iobase + offset);
435 }
436}
437
Alex Williamson40b36da2007-02-14 00:33:04 -0800438static void
439serial_out_sync(struct uart_8250_port *up, int offset, int value)
440{
441 switch (up->port.iotype) {
442 case UPIO_MEM:
443 case UPIO_MEM32:
444#ifdef CONFIG_SERIAL_8250_AU1X00
445 case UPIO_AU:
446#endif
Marc St-Jeanbeab6972007-05-06 14:48:45 -0700447 case UPIO_DWAPB:
Alex Williamson40b36da2007-02-14 00:33:04 -0800448 serial_out(up, offset, value);
449 serial_in(up, UART_LCR); /* safe, no side-effects */
450 break;
451 default:
452 serial_out(up, offset, value);
453 }
454}
455
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456/*
457 * We used to support using pause I/O for certain machines. We
458 * haven't supported this for a while, but just in case it's badly
459 * needed for certain old 386 machines, I've left these #define's
460 * in....
461 */
462#define serial_inp(up, offset) serial_in(up, offset)
463#define serial_outp(up, offset, value) serial_out(up, offset, value)
464
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100465/* Uart divisor latch read */
466static inline int _serial_dl_read(struct uart_8250_port *up)
467{
468 return serial_inp(up, UART_DLL) | serial_inp(up, UART_DLM) << 8;
469}
470
471/* Uart divisor latch write */
472static inline void _serial_dl_write(struct uart_8250_port *up, int value)
473{
474 serial_outp(up, UART_DLL, value & 0xff);
475 serial_outp(up, UART_DLM, value >> 8 & 0xff);
476}
477
Thomas Koellerbd71c182007-05-06 14:48:47 -0700478#if defined (CONFIG_SERIAL_8250_AU1X00)
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100479/* Au1x00 haven't got a standard divisor latch */
480static int serial_dl_read(struct uart_8250_port *up)
481{
482 if (up->port.iotype == UPIO_AU)
483 return __raw_readl(up->port.membase + 0x28);
484 else
485 return _serial_dl_read(up);
486}
487
488static void serial_dl_write(struct uart_8250_port *up, int value)
489{
490 if (up->port.iotype == UPIO_AU)
491 __raw_writel(value, up->port.membase + 0x28);
492 else
493 _serial_dl_write(up, value);
494}
Thomas Koellerbd71c182007-05-06 14:48:47 -0700495#elif defined (CONFIG_SERIAL_8250_RM9K)
496static int serial_dl_read(struct uart_8250_port *up)
497{
498 return (up->port.iotype == UPIO_RM9000) ?
499 (((__raw_readl(up->port.membase + 0x10) << 8) |
500 (__raw_readl(up->port.membase + 0x08) & 0xff)) & 0xffff) :
501 _serial_dl_read(up);
502}
503
504static void serial_dl_write(struct uart_8250_port *up, int value)
505{
506 if (up->port.iotype == UPIO_RM9000) {
507 __raw_writel(value, up->port.membase + 0x08);
508 __raw_writel(value >> 8, up->port.membase + 0x10);
509 } else {
510 _serial_dl_write(up, value);
511 }
512}
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100513#else
514#define serial_dl_read(up) _serial_dl_read(up)
515#define serial_dl_write(up, value) _serial_dl_write(up, value)
516#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517
518/*
519 * For the 16C950
520 */
521static void serial_icr_write(struct uart_8250_port *up, int offset, int value)
522{
523 serial_out(up, UART_SCR, offset);
524 serial_out(up, UART_ICR, value);
525}
526
527static unsigned int serial_icr_read(struct uart_8250_port *up, int offset)
528{
529 unsigned int value;
530
531 serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
532 serial_out(up, UART_SCR, offset);
533 value = serial_in(up, UART_ICR);
534 serial_icr_write(up, UART_ACR, up->acr);
535
536 return value;
537}
538
539/*
540 * FIFO support.
541 */
542static inline void serial8250_clear_fifos(struct uart_8250_port *p)
543{
544 if (p->capabilities & UART_CAP_FIFO) {
545 serial_outp(p, UART_FCR, UART_FCR_ENABLE_FIFO);
546 serial_outp(p, UART_FCR, UART_FCR_ENABLE_FIFO |
547 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
548 serial_outp(p, UART_FCR, 0);
549 }
550}
551
552/*
553 * IER sleep support. UARTs which have EFRs need the "extended
554 * capability" bit enabled. Note that on XR16C850s, we need to
555 * reset LCR to write to IER.
556 */
557static inline void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
558{
559 if (p->capabilities & UART_CAP_SLEEP) {
560 if (p->capabilities & UART_CAP_EFR) {
561 serial_outp(p, UART_LCR, 0xBF);
562 serial_outp(p, UART_EFR, UART_EFR_ECB);
563 serial_outp(p, UART_LCR, 0);
564 }
565 serial_outp(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
566 if (p->capabilities & UART_CAP_EFR) {
567 serial_outp(p, UART_LCR, 0xBF);
568 serial_outp(p, UART_EFR, 0);
569 serial_outp(p, UART_LCR, 0);
570 }
571 }
572}
573
574#ifdef CONFIG_SERIAL_8250_RSA
575/*
576 * Attempts to turn on the RSA FIFO. Returns zero on failure.
577 * We set the port uart clock rate if we succeed.
578 */
579static int __enable_rsa(struct uart_8250_port *up)
580{
581 unsigned char mode;
582 int result;
583
584 mode = serial_inp(up, UART_RSA_MSR);
585 result = mode & UART_RSA_MSR_FIFO;
586
587 if (!result) {
588 serial_outp(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
589 mode = serial_inp(up, UART_RSA_MSR);
590 result = mode & UART_RSA_MSR_FIFO;
591 }
592
593 if (result)
594 up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
595
596 return result;
597}
598
599static void enable_rsa(struct uart_8250_port *up)
600{
601 if (up->port.type == PORT_RSA) {
602 if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
603 spin_lock_irq(&up->port.lock);
604 __enable_rsa(up);
605 spin_unlock_irq(&up->port.lock);
606 }
607 if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
608 serial_outp(up, UART_RSA_FRR, 0);
609 }
610}
611
612/*
613 * Attempts to turn off the RSA FIFO. Returns zero on failure.
614 * It is unknown why interrupts were disabled in here. However,
615 * the caller is expected to preserve this behaviour by grabbing
616 * the spinlock before calling this function.
617 */
618static void disable_rsa(struct uart_8250_port *up)
619{
620 unsigned char mode;
621 int result;
622
623 if (up->port.type == PORT_RSA &&
624 up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
625 spin_lock_irq(&up->port.lock);
626
627 mode = serial_inp(up, UART_RSA_MSR);
628 result = !(mode & UART_RSA_MSR_FIFO);
629
630 if (!result) {
631 serial_outp(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
632 mode = serial_inp(up, UART_RSA_MSR);
633 result = !(mode & UART_RSA_MSR_FIFO);
634 }
635
636 if (result)
637 up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
638 spin_unlock_irq(&up->port.lock);
639 }
640}
641#endif /* CONFIG_SERIAL_8250_RSA */
642
643/*
644 * This is a quickie test to see how big the FIFO is.
645 * It doesn't work at all the time, more's the pity.
646 */
647static int size_fifo(struct uart_8250_port *up)
648{
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100649 unsigned char old_fcr, old_mcr, old_lcr;
650 unsigned short old_dl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 int count;
652
653 old_lcr = serial_inp(up, UART_LCR);
654 serial_outp(up, UART_LCR, 0);
655 old_fcr = serial_inp(up, UART_FCR);
656 old_mcr = serial_inp(up, UART_MCR);
657 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
658 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
659 serial_outp(up, UART_MCR, UART_MCR_LOOP);
660 serial_outp(up, UART_LCR, UART_LCR_DLAB);
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100661 old_dl = serial_dl_read(up);
662 serial_dl_write(up, 0x0001);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 serial_outp(up, UART_LCR, 0x03);
664 for (count = 0; count < 256; count++)
665 serial_outp(up, UART_TX, count);
666 mdelay(20);/* FIXME - schedule_timeout */
667 for (count = 0; (serial_inp(up, UART_LSR) & UART_LSR_DR) &&
668 (count < 256); count++)
669 serial_inp(up, UART_RX);
670 serial_outp(up, UART_FCR, old_fcr);
671 serial_outp(up, UART_MCR, old_mcr);
672 serial_outp(up, UART_LCR, UART_LCR_DLAB);
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100673 serial_dl_write(up, old_dl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 serial_outp(up, UART_LCR, old_lcr);
675
676 return count;
677}
678
679/*
680 * Read UART ID using the divisor method - set DLL and DLM to zero
681 * and the revision will be in DLL and device type in DLM. We
682 * preserve the device state across this.
683 */
684static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
685{
686 unsigned char old_dll, old_dlm, old_lcr;
687 unsigned int id;
688
689 old_lcr = serial_inp(p, UART_LCR);
690 serial_outp(p, UART_LCR, UART_LCR_DLAB);
691
692 old_dll = serial_inp(p, UART_DLL);
693 old_dlm = serial_inp(p, UART_DLM);
694
695 serial_outp(p, UART_DLL, 0);
696 serial_outp(p, UART_DLM, 0);
697
698 id = serial_inp(p, UART_DLL) | serial_inp(p, UART_DLM) << 8;
699
700 serial_outp(p, UART_DLL, old_dll);
701 serial_outp(p, UART_DLM, old_dlm);
702 serial_outp(p, UART_LCR, old_lcr);
703
704 return id;
705}
706
707/*
708 * This is a helper routine to autodetect StarTech/Exar/Oxsemi UART's.
709 * When this function is called we know it is at least a StarTech
710 * 16650 V2, but it might be one of several StarTech UARTs, or one of
711 * its clones. (We treat the broken original StarTech 16650 V1 as a
712 * 16550, and why not? Startech doesn't seem to even acknowledge its
713 * existence.)
Thomas Koellerbd71c182007-05-06 14:48:47 -0700714 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 * What evil have men's minds wrought...
716 */
717static void autoconfig_has_efr(struct uart_8250_port *up)
718{
719 unsigned int id1, id2, id3, rev;
720
721 /*
722 * Everything with an EFR has SLEEP
723 */
724 up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
725
726 /*
727 * First we check to see if it's an Oxford Semiconductor UART.
728 *
729 * If we have to do this here because some non-National
730 * Semiconductor clone chips lock up if you try writing to the
731 * LSR register (which serial_icr_read does)
732 */
733
734 /*
735 * Check for Oxford Semiconductor 16C950.
736 *
737 * EFR [4] must be set else this test fails.
738 *
739 * This shouldn't be necessary, but Mike Hudson (Exoray@isys.ca)
740 * claims that it's needed for 952 dual UART's (which are not
741 * recommended for new designs).
742 */
743 up->acr = 0;
744 serial_out(up, UART_LCR, 0xBF);
745 serial_out(up, UART_EFR, UART_EFR_ECB);
746 serial_out(up, UART_LCR, 0x00);
747 id1 = serial_icr_read(up, UART_ID1);
748 id2 = serial_icr_read(up, UART_ID2);
749 id3 = serial_icr_read(up, UART_ID3);
750 rev = serial_icr_read(up, UART_REV);
751
752 DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev);
753
754 if (id1 == 0x16 && id2 == 0xC9 &&
755 (id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) {
756 up->port.type = PORT_16C950;
Russell King4ba5e352005-06-23 10:43:04 +0100757
758 /*
759 * Enable work around for the Oxford Semiconductor 952 rev B
760 * chip which causes it to seriously miscalculate baud rates
761 * when DLL is 0.
762 */
763 if (id3 == 0x52 && rev == 0x01)
764 up->bugs |= UART_BUG_QUOT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 return;
766 }
Thomas Koellerbd71c182007-05-06 14:48:47 -0700767
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768 /*
769 * We check for a XR16C850 by setting DLL and DLM to 0, and then
770 * reading back DLL and DLM. The chip type depends on the DLM
771 * value read back:
772 * 0x10 - XR16C850 and the DLL contains the chip revision.
773 * 0x12 - XR16C2850.
774 * 0x14 - XR16C854.
775 */
776 id1 = autoconfig_read_divisor_id(up);
777 DEBUG_AUTOCONF("850id=%04x ", id1);
778
779 id2 = id1 >> 8;
780 if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 up->port.type = PORT_16850;
782 return;
783 }
784
785 /*
786 * It wasn't an XR16C850.
787 *
788 * We distinguish between the '654 and the '650 by counting
789 * how many bytes are in the FIFO. I'm using this for now,
790 * since that's the technique that was sent to me in the
791 * serial driver update, but I'm not convinced this works.
792 * I've had problems doing this in the past. -TYT
793 */
794 if (size_fifo(up) == 64)
795 up->port.type = PORT_16654;
796 else
797 up->port.type = PORT_16650V2;
798}
799
800/*
801 * We detected a chip without a FIFO. Only two fall into
802 * this category - the original 8250 and the 16450. The
803 * 16450 has a scratch register (accessible with LCR=0)
804 */
805static void autoconfig_8250(struct uart_8250_port *up)
806{
807 unsigned char scratch, status1, status2;
808
809 up->port.type = PORT_8250;
810
811 scratch = serial_in(up, UART_SCR);
812 serial_outp(up, UART_SCR, 0xa5);
813 status1 = serial_in(up, UART_SCR);
814 serial_outp(up, UART_SCR, 0x5a);
815 status2 = serial_in(up, UART_SCR);
816 serial_outp(up, UART_SCR, scratch);
817
818 if (status1 == 0xa5 && status2 == 0x5a)
819 up->port.type = PORT_16450;
820}
821
822static int broken_efr(struct uart_8250_port *up)
823{
824 /*
825 * Exar ST16C2550 "A2" devices incorrectly detect as
826 * having an EFR, and report an ID of 0x0201. See
827 * http://www.exar.com/info.php?pdf=dan180_oct2004.pdf
828 */
829 if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16)
830 return 1;
831
832 return 0;
833}
834
835/*
836 * We know that the chip has FIFOs. Does it have an EFR? The
837 * EFR is located in the same register position as the IIR and
838 * we know the top two bits of the IIR are currently set. The
839 * EFR should contain zero. Try to read the EFR.
840 */
841static void autoconfig_16550a(struct uart_8250_port *up)
842{
843 unsigned char status1, status2;
844 unsigned int iersave;
845
846 up->port.type = PORT_16550A;
847 up->capabilities |= UART_CAP_FIFO;
848
849 /*
850 * Check for presence of the EFR when DLAB is set.
851 * Only ST16C650V1 UARTs pass this test.
852 */
853 serial_outp(up, UART_LCR, UART_LCR_DLAB);
854 if (serial_in(up, UART_EFR) == 0) {
855 serial_outp(up, UART_EFR, 0xA8);
856 if (serial_in(up, UART_EFR) != 0) {
857 DEBUG_AUTOCONF("EFRv1 ");
858 up->port.type = PORT_16650;
859 up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
860 } else {
861 DEBUG_AUTOCONF("Motorola 8xxx DUART ");
862 }
863 serial_outp(up, UART_EFR, 0);
864 return;
865 }
866
867 /*
868 * Maybe it requires 0xbf to be written to the LCR.
869 * (other ST16C650V2 UARTs, TI16C752A, etc)
870 */
871 serial_outp(up, UART_LCR, 0xBF);
872 if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) {
873 DEBUG_AUTOCONF("EFRv2 ");
874 autoconfig_has_efr(up);
875 return;
876 }
877
878 /*
879 * Check for a National Semiconductor SuperIO chip.
880 * Attempt to switch to bank 2, read the value of the LOOP bit
881 * from EXCR1. Switch back to bank 0, change it in MCR. Then
882 * switch back to bank 2, read it from EXCR1 again and check
883 * it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 */
885 serial_outp(up, UART_LCR, 0);
886 status1 = serial_in(up, UART_MCR);
887 serial_outp(up, UART_LCR, 0xE0);
888 status2 = serial_in(up, 0x02); /* EXCR1 */
889
890 if (!((status2 ^ status1) & UART_MCR_LOOP)) {
891 serial_outp(up, UART_LCR, 0);
892 serial_outp(up, UART_MCR, status1 ^ UART_MCR_LOOP);
893 serial_outp(up, UART_LCR, 0xE0);
894 status2 = serial_in(up, 0x02); /* EXCR1 */
895 serial_outp(up, UART_LCR, 0);
896 serial_outp(up, UART_MCR, status1);
897
898 if ((status2 ^ status1) & UART_MCR_LOOP) {
David Woodhouse857dde22005-05-21 15:52:23 +0100899 unsigned short quot;
900
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901 serial_outp(up, UART_LCR, 0xE0);
David Woodhouse857dde22005-05-21 15:52:23 +0100902
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100903 quot = serial_dl_read(up);
David Woodhouse857dde22005-05-21 15:52:23 +0100904 quot <<= 3;
905
David Woodhouseb5b82df2007-05-17 14:27:39 +0800906 status1 = serial_in(up, 0x04); /* EXCR2 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907 status1 &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
908 status1 |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
909 serial_outp(up, 0x04, status1);
Thomas Koellerbd71c182007-05-06 14:48:47 -0700910
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +0100911 serial_dl_write(up, quot);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912
David Woodhouse857dde22005-05-21 15:52:23 +0100913 serial_outp(up, UART_LCR, 0);
914
915 up->port.uartclk = 921600*16;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 up->port.type = PORT_NS16550A;
917 up->capabilities |= UART_NATSEMI;
918 return;
919 }
920 }
921
922 /*
923 * No EFR. Try to detect a TI16750, which only sets bit 5 of
924 * the IIR when 64 byte FIFO mode is enabled when DLAB is set.
925 * Try setting it with and without DLAB set. Cheap clones
926 * set bit 5 without DLAB set.
927 */
928 serial_outp(up, UART_LCR, 0);
929 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
930 status1 = serial_in(up, UART_IIR) >> 5;
931 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
932 serial_outp(up, UART_LCR, UART_LCR_DLAB);
933 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
934 status2 = serial_in(up, UART_IIR) >> 5;
935 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
936 serial_outp(up, UART_LCR, 0);
937
938 DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2);
939
940 if (status1 == 6 && status2 == 7) {
941 up->port.type = PORT_16750;
942 up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP;
943 return;
944 }
945
946 /*
947 * Try writing and reading the UART_IER_UUE bit (b6).
948 * If it works, this is probably one of the Xscale platform's
949 * internal UARTs.
950 * We're going to explicitly set the UUE bit to 0 before
951 * trying to write and read a 1 just to make sure it's not
952 * already a 1 and maybe locked there before we even start start.
953 */
954 iersave = serial_in(up, UART_IER);
955 serial_outp(up, UART_IER, iersave & ~UART_IER_UUE);
956 if (!(serial_in(up, UART_IER) & UART_IER_UUE)) {
957 /*
958 * OK it's in a known zero state, try writing and reading
959 * without disturbing the current state of the other bits.
960 */
961 serial_outp(up, UART_IER, iersave | UART_IER_UUE);
962 if (serial_in(up, UART_IER) & UART_IER_UUE) {
963 /*
964 * It's an Xscale.
965 * We'll leave the UART_IER_UUE bit set to 1 (enabled).
966 */
967 DEBUG_AUTOCONF("Xscale ");
968 up->port.type = PORT_XSCALE;
969 up->capabilities |= UART_CAP_UUE;
970 return;
971 }
972 } else {
973 /*
974 * If we got here we couldn't force the IER_UUE bit to 0.
975 * Log it and continue.
976 */
977 DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 ");
978 }
979 serial_outp(up, UART_IER, iersave);
980}
981
982/*
983 * This routine is called by rs_init() to initialize a specific serial
984 * port. It determines what type of UART chip this serial port is
985 * using: 8250, 16450, 16550, 16550A. The important question is
986 * whether or not this UART is a 16550A or not, since this will
987 * determine whether or not we can use its FIFO features or not.
988 */
989static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
990{
991 unsigned char status1, scratch, scratch2, scratch3;
992 unsigned char save_lcr, save_mcr;
993 unsigned long flags;
994
995 if (!up->port.iobase && !up->port.mapbase && !up->port.membase)
996 return;
997
998 DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%p): ",
999 up->port.line, up->port.iobase, up->port.membase);
1000
1001 /*
1002 * We really do need global IRQs disabled here - we're going to
1003 * be frobbing the chips IRQ enable register to see if it exists.
1004 */
1005 spin_lock_irqsave(&up->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006
1007 up->capabilities = 0;
Russell King4ba5e352005-06-23 10:43:04 +01001008 up->bugs = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009
1010 if (!(up->port.flags & UPF_BUGGY_UART)) {
1011 /*
1012 * Do a simple existence test first; if we fail this,
1013 * there's no point trying anything else.
Thomas Koellerbd71c182007-05-06 14:48:47 -07001014 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 * 0x80 is used as a nonsense port to prevent against
1016 * false positives due to ISA bus float. The
1017 * assumption is that 0x80 is a non-existent port;
1018 * which should be safe since include/asm/io.h also
1019 * makes this assumption.
1020 *
1021 * Note: this is safe as long as MCR bit 4 is clear
1022 * and the device is in "PC" mode.
1023 */
1024 scratch = serial_inp(up, UART_IER);
1025 serial_outp(up, UART_IER, 0);
1026#ifdef __i386__
1027 outb(0xff, 0x080);
1028#endif
Thomas Hoehn48212002007-02-10 01:46:05 -08001029 /*
1030 * Mask out IER[7:4] bits for test as some UARTs (e.g. TL
1031 * 16C754B) allow only to modify them if an EFR bit is set.
1032 */
1033 scratch2 = serial_inp(up, UART_IER) & 0x0f;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034 serial_outp(up, UART_IER, 0x0F);
1035#ifdef __i386__
1036 outb(0, 0x080);
1037#endif
Thomas Hoehn48212002007-02-10 01:46:05 -08001038 scratch3 = serial_inp(up, UART_IER) & 0x0f;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039 serial_outp(up, UART_IER, scratch);
1040 if (scratch2 != 0 || scratch3 != 0x0F) {
1041 /*
1042 * We failed; there's nothing here
1043 */
1044 DEBUG_AUTOCONF("IER test failed (%02x, %02x) ",
1045 scratch2, scratch3);
1046 goto out;
1047 }
1048 }
1049
1050 save_mcr = serial_in(up, UART_MCR);
1051 save_lcr = serial_in(up, UART_LCR);
1052
Thomas Koellerbd71c182007-05-06 14:48:47 -07001053 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054 * Check to see if a UART is really there. Certain broken
1055 * internal modems based on the Rockwell chipset fail this
1056 * test, because they apparently don't implement the loopback
1057 * test mode. So this test is skipped on the COM 1 through
1058 * COM 4 ports. This *should* be safe, since no board
1059 * manufacturer would be stupid enough to design a board
1060 * that conflicts with COM 1-4 --- we hope!
1061 */
1062 if (!(up->port.flags & UPF_SKIP_TEST)) {
1063 serial_outp(up, UART_MCR, UART_MCR_LOOP | 0x0A);
1064 status1 = serial_inp(up, UART_MSR) & 0xF0;
1065 serial_outp(up, UART_MCR, save_mcr);
1066 if (status1 != 0x90) {
1067 DEBUG_AUTOCONF("LOOP test failed (%02x) ",
1068 status1);
1069 goto out;
1070 }
1071 }
1072
1073 /*
1074 * We're pretty sure there's a port here. Lets find out what
1075 * type of port it is. The IIR top two bits allows us to find
Russell King6f0d6182005-09-09 16:17:58 +01001076 * out if it's 8250 or 16450, 16550, 16550A or later. This
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077 * determines what we test for next.
1078 *
1079 * We also initialise the EFR (if any) to zero for later. The
1080 * EFR occupies the same register location as the FCR and IIR.
1081 */
1082 serial_outp(up, UART_LCR, 0xBF);
1083 serial_outp(up, UART_EFR, 0);
1084 serial_outp(up, UART_LCR, 0);
1085
1086 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
1087 scratch = serial_in(up, UART_IIR) >> 6;
1088
1089 DEBUG_AUTOCONF("iir=%d ", scratch);
1090
1091 switch (scratch) {
1092 case 0:
1093 autoconfig_8250(up);
1094 break;
1095 case 1:
1096 up->port.type = PORT_UNKNOWN;
1097 break;
1098 case 2:
1099 up->port.type = PORT_16550;
1100 break;
1101 case 3:
1102 autoconfig_16550a(up);
1103 break;
1104 }
1105
1106#ifdef CONFIG_SERIAL_8250_RSA
1107 /*
1108 * Only probe for RSA ports if we got the region.
1109 */
1110 if (up->port.type == PORT_16550A && probeflags & PROBE_RSA) {
1111 int i;
1112
1113 for (i = 0 ; i < probe_rsa_count; ++i) {
1114 if (probe_rsa[i] == up->port.iobase &&
1115 __enable_rsa(up)) {
1116 up->port.type = PORT_RSA;
1117 break;
1118 }
1119 }
1120 }
1121#endif
Pantelis Antoniou21c614a2005-11-06 09:07:03 +00001122
1123#ifdef CONFIG_SERIAL_8250_AU1X00
1124 /* if access method is AU, it is a 16550 with a quirk */
1125 if (up->port.type == PORT_16550A && up->port.iotype == UPIO_AU)
1126 up->bugs |= UART_BUG_NOMSR;
1127#endif
1128
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129 serial_outp(up, UART_LCR, save_lcr);
1130
1131 if (up->capabilities != uart_config[up->port.type].flags) {
1132 printk(KERN_WARNING
1133 "ttyS%d: detected caps %08x should be %08x\n",
1134 up->port.line, up->capabilities,
1135 uart_config[up->port.type].flags);
1136 }
1137
1138 up->port.fifosize = uart_config[up->port.type].fifo_size;
1139 up->capabilities = uart_config[up->port.type].flags;
1140 up->tx_loadsz = uart_config[up->port.type].tx_loadsz;
1141
1142 if (up->port.type == PORT_UNKNOWN)
1143 goto out;
1144
1145 /*
1146 * Reset the UART.
1147 */
1148#ifdef CONFIG_SERIAL_8250_RSA
1149 if (up->port.type == PORT_RSA)
1150 serial_outp(up, UART_RSA_FRR, 0);
1151#endif
1152 serial_outp(up, UART_MCR, save_mcr);
1153 serial8250_clear_fifos(up);
Alex Williamson40b36da2007-02-14 00:33:04 -08001154 serial_in(up, UART_RX);
Lennert Buytenhek5c8c7552005-11-12 21:58:05 +00001155 if (up->capabilities & UART_CAP_UUE)
1156 serial_outp(up, UART_IER, UART_IER_UUE);
1157 else
1158 serial_outp(up, UART_IER, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001159
Thomas Koellerbd71c182007-05-06 14:48:47 -07001160 out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001161 spin_unlock_irqrestore(&up->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162 DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name);
1163}
1164
1165static void autoconfig_irq(struct uart_8250_port *up)
1166{
1167 unsigned char save_mcr, save_ier;
1168 unsigned char save_ICP = 0;
1169 unsigned int ICP = 0;
1170 unsigned long irqs;
1171 int irq;
1172
1173 if (up->port.flags & UPF_FOURPORT) {
1174 ICP = (up->port.iobase & 0xfe0) | 0x1f;
1175 save_ICP = inb_p(ICP);
1176 outb_p(0x80, ICP);
1177 (void) inb_p(ICP);
1178 }
1179
1180 /* forget possible initially masked and pending IRQ */
1181 probe_irq_off(probe_irq_on());
1182 save_mcr = serial_inp(up, UART_MCR);
1183 save_ier = serial_inp(up, UART_IER);
1184 serial_outp(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2);
Thomas Koellerbd71c182007-05-06 14:48:47 -07001185
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 irqs = probe_irq_on();
1187 serial_outp(up, UART_MCR, 0);
1188 udelay (10);
1189 if (up->port.flags & UPF_FOURPORT) {
1190 serial_outp(up, UART_MCR,
1191 UART_MCR_DTR | UART_MCR_RTS);
1192 } else {
1193 serial_outp(up, UART_MCR,
1194 UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
1195 }
1196 serial_outp(up, UART_IER, 0x0f); /* enable all intrs */
1197 (void)serial_inp(up, UART_LSR);
1198 (void)serial_inp(up, UART_RX);
1199 (void)serial_inp(up, UART_IIR);
1200 (void)serial_inp(up, UART_MSR);
1201 serial_outp(up, UART_TX, 0xFF);
1202 udelay (20);
1203 irq = probe_irq_off(irqs);
1204
1205 serial_outp(up, UART_MCR, save_mcr);
1206 serial_outp(up, UART_IER, save_ier);
1207
1208 if (up->port.flags & UPF_FOURPORT)
1209 outb_p(save_ICP, ICP);
1210
1211 up->port.irq = (irq > 0) ? irq : 0;
1212}
1213
Russell Kinge763b902005-06-29 18:41:51 +01001214static inline void __stop_tx(struct uart_8250_port *p)
1215{
1216 if (p->ier & UART_IER_THRI) {
1217 p->ier &= ~UART_IER_THRI;
1218 serial_out(p, UART_IER, p->ier);
1219 }
1220}
1221
Russell Kingb129a8c2005-08-31 10:12:14 +01001222static void serial8250_stop_tx(struct uart_port *port)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223{
1224 struct uart_8250_port *up = (struct uart_8250_port *)port;
1225
Russell Kinge763b902005-06-29 18:41:51 +01001226 __stop_tx(up);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227
1228 /*
Russell Kinge763b902005-06-29 18:41:51 +01001229 * We really want to stop the transmitter from sending.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001230 */
Russell Kinge763b902005-06-29 18:41:51 +01001231 if (up->port.type == PORT_16C950) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232 up->acr |= UART_ACR_TXDIS;
1233 serial_icr_write(up, UART_ACR, up->acr);
1234 }
1235}
1236
Russell King55d3b282005-06-23 15:05:41 +01001237static void transmit_chars(struct uart_8250_port *up);
1238
Russell Kingb129a8c2005-08-31 10:12:14 +01001239static void serial8250_start_tx(struct uart_port *port)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240{
1241 struct uart_8250_port *up = (struct uart_8250_port *)port;
1242
1243 if (!(up->ier & UART_IER_THRI)) {
1244 up->ier |= UART_IER_THRI;
1245 serial_out(up, UART_IER, up->ier);
Russell King55d3b282005-06-23 15:05:41 +01001246
Russell King67f76542005-06-23 22:26:43 +01001247 if (up->bugs & UART_BUG_TXEN) {
Russell King55d3b282005-06-23 15:05:41 +01001248 unsigned char lsr, iir;
1249 lsr = serial_in(up, UART_LSR);
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001250 up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
Thomas Koellerbd71c182007-05-06 14:48:47 -07001251 iir = serial_in(up, UART_IIR) & 0x0f;
1252 if ((up->port.type == PORT_RM9000) ?
1253 (lsr & UART_LSR_THRE &&
1254 (iir == UART_IIR_NO_INT || iir == UART_IIR_THRI)) :
1255 (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT))
Russell King55d3b282005-06-23 15:05:41 +01001256 transmit_chars(up);
1257 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 }
Russell Kinge763b902005-06-29 18:41:51 +01001259
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260 /*
Russell Kinge763b902005-06-29 18:41:51 +01001261 * Re-enable the transmitter if we disabled it.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 */
Russell Kinge763b902005-06-29 18:41:51 +01001263 if (up->port.type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001264 up->acr &= ~UART_ACR_TXDIS;
1265 serial_icr_write(up, UART_ACR, up->acr);
1266 }
1267}
1268
1269static void serial8250_stop_rx(struct uart_port *port)
1270{
1271 struct uart_8250_port *up = (struct uart_8250_port *)port;
1272
1273 up->ier &= ~UART_IER_RLSI;
1274 up->port.read_status_mask &= ~UART_LSR_DR;
1275 serial_out(up, UART_IER, up->ier);
1276}
1277
1278static void serial8250_enable_ms(struct uart_port *port)
1279{
1280 struct uart_8250_port *up = (struct uart_8250_port *)port;
1281
Pantelis Antoniou21c614a2005-11-06 09:07:03 +00001282 /* no MSR capabilities */
1283 if (up->bugs & UART_BUG_NOMSR)
1284 return;
1285
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 up->ier |= UART_IER_MSI;
1287 serial_out(up, UART_IER, up->ier);
1288}
1289
Russell Kingea8874d2006-01-04 19:43:24 +00001290static void
Thomas Koellercc79aa92007-02-20 13:58:05 -08001291receive_chars(struct uart_8250_port *up, unsigned int *status)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292{
1293 struct tty_struct *tty = up->port.info->tty;
1294 unsigned char ch, lsr = *status;
1295 int max_count = 256;
1296 char flag;
1297
1298 do {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 ch = serial_inp(up, UART_RX);
1300 flag = TTY_NORMAL;
1301 up->port.icount.rx++;
1302
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001303 lsr |= up->lsr_saved_flags;
1304 up->lsr_saved_flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001306 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307 /*
1308 * For statistics only
1309 */
1310 if (lsr & UART_LSR_BI) {
1311 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
1312 up->port.icount.brk++;
1313 /*
1314 * We do the SysRQ and SAK checking
1315 * here because otherwise the break
1316 * may get masked by ignore_status_mask
1317 * or read_status_mask.
1318 */
1319 if (uart_handle_break(&up->port))
1320 goto ignore_char;
1321 } else if (lsr & UART_LSR_PE)
1322 up->port.icount.parity++;
1323 else if (lsr & UART_LSR_FE)
1324 up->port.icount.frame++;
1325 if (lsr & UART_LSR_OE)
1326 up->port.icount.overrun++;
1327
1328 /*
Russell King23907eb2005-04-16 15:26:39 -07001329 * Mask off conditions which should be ignored.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001330 */
1331 lsr &= up->port.read_status_mask;
1332
1333 if (lsr & UART_LSR_BI) {
1334 DEBUG_INTR("handling break....");
1335 flag = TTY_BREAK;
1336 } else if (lsr & UART_LSR_PE)
1337 flag = TTY_PARITY;
1338 else if (lsr & UART_LSR_FE)
1339 flag = TTY_FRAME;
1340 }
David Howells7d12e782006-10-05 14:55:46 +01001341 if (uart_handle_sysrq_char(&up->port, ch))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342 goto ignore_char;
Russell King05ab3012005-05-09 23:21:59 +01001343
1344 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
1345
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 ignore_char:
1347 lsr = serial_inp(up, UART_LSR);
1348 } while ((lsr & UART_LSR_DR) && (max_count-- > 0));
1349 spin_unlock(&up->port.lock);
1350 tty_flip_buffer_push(tty);
1351 spin_lock(&up->port.lock);
1352 *status = lsr;
1353}
1354
Russell Kingea8874d2006-01-04 19:43:24 +00001355static void transmit_chars(struct uart_8250_port *up)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356{
1357 struct circ_buf *xmit = &up->port.info->xmit;
1358 int count;
1359
1360 if (up->port.x_char) {
1361 serial_outp(up, UART_TX, up->port.x_char);
1362 up->port.icount.tx++;
1363 up->port.x_char = 0;
1364 return;
1365 }
Russell Kingb129a8c2005-08-31 10:12:14 +01001366 if (uart_tx_stopped(&up->port)) {
1367 serial8250_stop_tx(&up->port);
1368 return;
1369 }
1370 if (uart_circ_empty(xmit)) {
Russell Kinge763b902005-06-29 18:41:51 +01001371 __stop_tx(up);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372 return;
1373 }
1374
1375 count = up->tx_loadsz;
1376 do {
1377 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
1378 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
1379 up->port.icount.tx++;
1380 if (uart_circ_empty(xmit))
1381 break;
1382 } while (--count > 0);
1383
1384 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1385 uart_write_wakeup(&up->port);
1386
1387 DEBUG_INTR("THRE...");
1388
1389 if (uart_circ_empty(xmit))
Russell Kinge763b902005-06-29 18:41:51 +01001390 __stop_tx(up);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001391}
1392
Russell King2af7cd62006-01-04 16:55:09 +00001393static unsigned int check_modem_status(struct uart_8250_port *up)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394{
Russell King2af7cd62006-01-04 16:55:09 +00001395 unsigned int status = serial_in(up, UART_MSR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001397 status |= up->msr_saved_flags;
1398 up->msr_saved_flags = 0;
Taku Izumifdc30b32007-04-23 14:41:00 -07001399 if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
1400 up->port.info != NULL) {
Russell King2af7cd62006-01-04 16:55:09 +00001401 if (status & UART_MSR_TERI)
1402 up->port.icount.rng++;
1403 if (status & UART_MSR_DDSR)
1404 up->port.icount.dsr++;
1405 if (status & UART_MSR_DDCD)
1406 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
1407 if (status & UART_MSR_DCTS)
1408 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001409
Russell King2af7cd62006-01-04 16:55:09 +00001410 wake_up_interruptible(&up->port.info->delta_msr_wait);
1411 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001412
Russell King2af7cd62006-01-04 16:55:09 +00001413 return status;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001414}
1415
1416/*
1417 * This handles the interrupt from one port.
1418 */
1419static inline void
David Howells7d12e782006-10-05 14:55:46 +01001420serial8250_handle_port(struct uart_8250_port *up)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421{
Russell King45e24602006-01-04 19:19:06 +00001422 unsigned int status;
Jiri Kosina4bf36312007-04-23 14:41:21 -07001423 unsigned long flags;
Russell King45e24602006-01-04 19:19:06 +00001424
Jiri Kosina4bf36312007-04-23 14:41:21 -07001425 spin_lock_irqsave(&up->port.lock, flags);
Russell King45e24602006-01-04 19:19:06 +00001426
1427 status = serial_inp(up, UART_LSR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001428
1429 DEBUG_INTR("status = %x...", status);
1430
1431 if (status & UART_LSR_DR)
David Howells7d12e782006-10-05 14:55:46 +01001432 receive_chars(up, &status);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001433 check_modem_status(up);
1434 if (status & UART_LSR_THRE)
1435 transmit_chars(up);
Russell King45e24602006-01-04 19:19:06 +00001436
Jiri Kosina4bf36312007-04-23 14:41:21 -07001437 spin_unlock_irqrestore(&up->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438}
1439
1440/*
1441 * This is the serial driver's interrupt routine.
1442 *
1443 * Arjan thinks the old way was overly complex, so it got simplified.
1444 * Alan disagrees, saying that need the complexity to handle the weird
1445 * nature of ISA shared interrupts. (This is a special exception.)
1446 *
1447 * In order to handle ISA shared interrupts properly, we need to check
1448 * that all ports have been serviced, and therefore the ISA interrupt
1449 * line has been de-asserted.
1450 *
1451 * This means we need to loop through all ports. checking that they
1452 * don't have an interrupt pending.
1453 */
David Howells7d12e782006-10-05 14:55:46 +01001454static irqreturn_t serial8250_interrupt(int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001455{
1456 struct irq_info *i = dev_id;
1457 struct list_head *l, *end = NULL;
1458 int pass_counter = 0, handled = 0;
1459
1460 DEBUG_INTR("serial8250_interrupt(%d)...", irq);
1461
1462 spin_lock(&i->lock);
1463
1464 l = i->head;
1465 do {
1466 struct uart_8250_port *up;
1467 unsigned int iir;
1468
1469 up = list_entry(l, struct uart_8250_port, list);
1470
1471 iir = serial_in(up, UART_IIR);
1472 if (!(iir & UART_IIR_NO_INT)) {
David Howells7d12e782006-10-05 14:55:46 +01001473 serial8250_handle_port(up);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474
1475 handled = 1;
1476
1477 end = NULL;
Marc St-Jeanbeab6972007-05-06 14:48:45 -07001478 } else if (up->port.iotype == UPIO_DWAPB &&
1479 (iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
1480 /* The DesignWare APB UART has an Busy Detect (0x07)
1481 * interrupt meaning an LCR write attempt occured while the
1482 * UART was busy. The interrupt must be cleared by reading
1483 * the UART status register (USR) and the LCR re-written. */
1484 unsigned int status;
1485 status = *(volatile u32 *)up->port.private_data;
1486 serial_out(up, UART_LCR, up->lcr);
1487
1488 handled = 1;
1489
1490 end = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491 } else if (end == NULL)
1492 end = l;
1493
1494 l = l->next;
1495
1496 if (l == i->head && pass_counter++ > PASS_LIMIT) {
1497 /* If we hit this, we're dead. */
1498 printk(KERN_ERR "serial8250: too much work for "
1499 "irq%d\n", irq);
1500 break;
1501 }
1502 } while (l != end);
1503
1504 spin_unlock(&i->lock);
1505
1506 DEBUG_INTR("end.\n");
1507
1508 return IRQ_RETVAL(handled);
1509}
1510
1511/*
1512 * To support ISA shared interrupts, we need to have one interrupt
1513 * handler that ensures that the IRQ line has been deasserted
1514 * before returning. Failing to do this will result in the IRQ
1515 * line being stuck active, and, since ISA irqs are edge triggered,
1516 * no more IRQs will be seen.
1517 */
1518static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
1519{
1520 spin_lock_irq(&i->lock);
1521
1522 if (!list_empty(i->head)) {
1523 if (i->head == &up->list)
1524 i->head = i->head->next;
1525 list_del(&up->list);
1526 } else {
1527 BUG_ON(i->head != &up->list);
1528 i->head = NULL;
1529 }
1530
1531 spin_unlock_irq(&i->lock);
1532}
1533
1534static int serial_link_irq_chain(struct uart_8250_port *up)
1535{
1536 struct irq_info *i = irq_lists + up->port.irq;
Thomas Gleixner40663cc2006-07-01 19:29:43 -07001537 int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001538
1539 spin_lock_irq(&i->lock);
1540
1541 if (i->head) {
1542 list_add(&up->list, i->head);
1543 spin_unlock_irq(&i->lock);
1544
1545 ret = 0;
1546 } else {
1547 INIT_LIST_HEAD(&up->list);
1548 i->head = &up->list;
1549 spin_unlock_irq(&i->lock);
1550
1551 ret = request_irq(up->port.irq, serial8250_interrupt,
1552 irq_flags, "serial", i);
1553 if (ret < 0)
1554 serial_do_unlink(i, up);
1555 }
1556
1557 return ret;
1558}
1559
1560static void serial_unlink_irq_chain(struct uart_8250_port *up)
1561{
1562 struct irq_info *i = irq_lists + up->port.irq;
1563
1564 BUG_ON(i->head == NULL);
1565
1566 if (list_empty(i->head))
1567 free_irq(up->port.irq, i);
1568
1569 serial_do_unlink(i, up);
1570}
1571
Alex Williamson40b36da2007-02-14 00:33:04 -08001572/* Base timer interval for polling */
1573static inline int poll_timeout(int timeout)
1574{
1575 return timeout > 6 ? (timeout / 2 - 2) : 1;
1576}
1577
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578/*
1579 * This function is used to handle ports that do not have an
1580 * interrupt. This doesn't work very well for 16450's, but gives
1581 * barely passable results for a 16550A. (Although at the expense
1582 * of much CPU overhead).
1583 */
1584static void serial8250_timeout(unsigned long data)
1585{
1586 struct uart_8250_port *up = (struct uart_8250_port *)data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587 unsigned int iir;
1588
1589 iir = serial_in(up, UART_IIR);
Russell King45e24602006-01-04 19:19:06 +00001590 if (!(iir & UART_IIR_NO_INT))
David Howells7d12e782006-10-05 14:55:46 +01001591 serial8250_handle_port(up);
Alex Williamson40b36da2007-02-14 00:33:04 -08001592 mod_timer(&up->timer, jiffies + poll_timeout(up->port.timeout));
1593}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001594
Alex Williamson40b36da2007-02-14 00:33:04 -08001595static void serial8250_backup_timeout(unsigned long data)
1596{
1597 struct uart_8250_port *up = (struct uart_8250_port *)data;
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001598 unsigned int iir, ier = 0, lsr;
1599 unsigned long flags;
Alex Williamson40b36da2007-02-14 00:33:04 -08001600
1601 /*
1602 * Must disable interrupts or else we risk racing with the interrupt
1603 * based handler.
1604 */
1605 if (is_real_interrupt(up->port.irq)) {
1606 ier = serial_in(up, UART_IER);
1607 serial_out(up, UART_IER, 0);
1608 }
1609
1610 iir = serial_in(up, UART_IIR);
1611
1612 /*
1613 * This should be a safe test for anyone who doesn't trust the
1614 * IIR bits on their UART, but it's specifically designed for
1615 * the "Diva" UART used on the management processor on many HP
1616 * ia64 and parisc boxes.
1617 */
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001618 spin_lock_irqsave(&up->port.lock, flags);
1619 lsr = serial_in(up, UART_LSR);
1620 up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
1621 spin_unlock_irqrestore(&up->port.lock, flags);
Alex Williamson40b36da2007-02-14 00:33:04 -08001622 if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) &&
1623 (!uart_circ_empty(&up->port.info->xmit) || up->port.x_char) &&
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001624 (lsr & UART_LSR_THRE)) {
Alex Williamson40b36da2007-02-14 00:33:04 -08001625 iir &= ~(UART_IIR_ID | UART_IIR_NO_INT);
1626 iir |= UART_IIR_THRI;
1627 }
1628
1629 if (!(iir & UART_IIR_NO_INT))
1630 serial8250_handle_port(up);
1631
1632 if (is_real_interrupt(up->port.irq))
1633 serial_out(up, UART_IER, ier);
1634
1635 /* Standard timer interval plus 0.2s to keep the port running */
1636 mod_timer(&up->timer, jiffies + poll_timeout(up->port.timeout) + HZ/5);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637}
1638
1639static unsigned int serial8250_tx_empty(struct uart_port *port)
1640{
1641 struct uart_8250_port *up = (struct uart_8250_port *)port;
1642 unsigned long flags;
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001643 unsigned int lsr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001644
1645 spin_lock_irqsave(&up->port.lock, flags);
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001646 lsr = serial_in(up, UART_LSR);
1647 up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001648 spin_unlock_irqrestore(&up->port.lock, flags);
1649
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001650 return lsr & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651}
1652
1653static unsigned int serial8250_get_mctrl(struct uart_port *port)
1654{
1655 struct uart_8250_port *up = (struct uart_8250_port *)port;
Russell King2af7cd62006-01-04 16:55:09 +00001656 unsigned int status;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 unsigned int ret;
1658
Russell King2af7cd62006-01-04 16:55:09 +00001659 status = check_modem_status(up);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001660
1661 ret = 0;
1662 if (status & UART_MSR_DCD)
1663 ret |= TIOCM_CAR;
1664 if (status & UART_MSR_RI)
1665 ret |= TIOCM_RNG;
1666 if (status & UART_MSR_DSR)
1667 ret |= TIOCM_DSR;
1668 if (status & UART_MSR_CTS)
1669 ret |= TIOCM_CTS;
1670 return ret;
1671}
1672
1673static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
1674{
1675 struct uart_8250_port *up = (struct uart_8250_port *)port;
1676 unsigned char mcr = 0;
1677
1678 if (mctrl & TIOCM_RTS)
1679 mcr |= UART_MCR_RTS;
1680 if (mctrl & TIOCM_DTR)
1681 mcr |= UART_MCR_DTR;
1682 if (mctrl & TIOCM_OUT1)
1683 mcr |= UART_MCR_OUT1;
1684 if (mctrl & TIOCM_OUT2)
1685 mcr |= UART_MCR_OUT2;
1686 if (mctrl & TIOCM_LOOP)
1687 mcr |= UART_MCR_LOOP;
1688
1689 mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr;
1690
1691 serial_out(up, UART_MCR, mcr);
1692}
1693
1694static void serial8250_break_ctl(struct uart_port *port, int break_state)
1695{
1696 struct uart_8250_port *up = (struct uart_8250_port *)port;
1697 unsigned long flags;
1698
1699 spin_lock_irqsave(&up->port.lock, flags);
1700 if (break_state == -1)
1701 up->lcr |= UART_LCR_SBC;
1702 else
1703 up->lcr &= ~UART_LCR_SBC;
1704 serial_out(up, UART_LCR, up->lcr);
1705 spin_unlock_irqrestore(&up->port.lock, flags);
1706}
1707
Alex Williamson40b36da2007-02-14 00:33:04 -08001708#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1709
1710/*
1711 * Wait for transmitter & holding register to empty
1712 */
1713static inline void wait_for_xmitr(struct uart_8250_port *up, int bits)
1714{
1715 unsigned int status, tmout = 10000;
1716
1717 /* Wait up to 10ms for the character(s) to be sent. */
1718 do {
1719 status = serial_in(up, UART_LSR);
1720
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001721 up->lsr_saved_flags |= status & LSR_SAVE_FLAGS;
Alex Williamson40b36da2007-02-14 00:33:04 -08001722
1723 if (--tmout == 0)
1724 break;
1725 udelay(1);
1726 } while ((status & bits) != bits);
1727
1728 /* Wait up to 1s for flow control if necessary */
1729 if (up->port.flags & UPF_CONS_FLOW) {
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001730 unsigned int tmout;
1731 for (tmout = 1000000; tmout; tmout--) {
1732 unsigned int msr = serial_in(up, UART_MSR);
1733 up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1734 if (msr & UART_MSR_CTS)
1735 break;
Alex Williamson40b36da2007-02-14 00:33:04 -08001736 udelay(1);
1737 touch_nmi_watchdog();
1738 }
1739 }
1740}
1741
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742static int serial8250_startup(struct uart_port *port)
1743{
1744 struct uart_8250_port *up = (struct uart_8250_port *)port;
1745 unsigned long flags;
Russell King55d3b282005-06-23 15:05:41 +01001746 unsigned char lsr, iir;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001747 int retval;
1748
1749 up->capabilities = uart_config[up->port.type].flags;
1750 up->mcr = 0;
1751
1752 if (up->port.type == PORT_16C950) {
1753 /* Wake up and initialize UART */
1754 up->acr = 0;
1755 serial_outp(up, UART_LCR, 0xBF);
1756 serial_outp(up, UART_EFR, UART_EFR_ECB);
1757 serial_outp(up, UART_IER, 0);
1758 serial_outp(up, UART_LCR, 0);
1759 serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
1760 serial_outp(up, UART_LCR, 0xBF);
1761 serial_outp(up, UART_EFR, UART_EFR_ECB);
1762 serial_outp(up, UART_LCR, 0);
1763 }
1764
1765#ifdef CONFIG_SERIAL_8250_RSA
1766 /*
1767 * If this is an RSA port, see if we can kick it up to the
1768 * higher speed clock.
1769 */
1770 enable_rsa(up);
1771#endif
1772
1773 /*
1774 * Clear the FIFO buffers and disable them.
Alexey Dobriyan7f927fc2006-03-28 01:56:53 -08001775 * (they will be reenabled in set_termios())
Linus Torvalds1da177e2005-04-16 15:20:36 -07001776 */
1777 serial8250_clear_fifos(up);
1778
1779 /*
1780 * Clear the interrupt registers.
1781 */
1782 (void) serial_inp(up, UART_LSR);
1783 (void) serial_inp(up, UART_RX);
1784 (void) serial_inp(up, UART_IIR);
1785 (void) serial_inp(up, UART_MSR);
1786
1787 /*
1788 * At this point, there's no way the LSR could still be 0xff;
1789 * if it is, then bail out, because there's likely no UART
1790 * here.
1791 */
1792 if (!(up->port.flags & UPF_BUGGY_UART) &&
1793 (serial_inp(up, UART_LSR) == 0xff)) {
1794 printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
1795 return -ENODEV;
1796 }
1797
1798 /*
1799 * For a XR16C850, we need to set the trigger levels
1800 */
1801 if (up->port.type == PORT_16850) {
1802 unsigned char fctr;
1803
1804 serial_outp(up, UART_LCR, 0xbf);
1805
1806 fctr = serial_inp(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
1807 serial_outp(up, UART_FCTR, fctr | UART_FCTR_TRGD | UART_FCTR_RX);
1808 serial_outp(up, UART_TRG, UART_TRG_96);
1809 serial_outp(up, UART_FCTR, fctr | UART_FCTR_TRGD | UART_FCTR_TX);
1810 serial_outp(up, UART_TRG, UART_TRG_96);
1811
1812 serial_outp(up, UART_LCR, 0);
1813 }
1814
Alex Williamson40b36da2007-02-14 00:33:04 -08001815 if (is_real_interrupt(up->port.irq)) {
1816 /*
1817 * Test for UARTs that do not reassert THRE when the
1818 * transmitter is idle and the interrupt has already
1819 * been cleared. Real 16550s should always reassert
1820 * this interrupt whenever the transmitter is idle and
1821 * the interrupt is enabled. Delays are necessary to
1822 * allow register changes to become visible.
1823 */
1824 spin_lock_irqsave(&up->port.lock, flags);
1825
1826 wait_for_xmitr(up, UART_LSR_THRE);
1827 serial_out_sync(up, UART_IER, UART_IER_THRI);
1828 udelay(1); /* allow THRE to set */
1829 serial_in(up, UART_IIR);
1830 serial_out(up, UART_IER, 0);
1831 serial_out_sync(up, UART_IER, UART_IER_THRI);
1832 udelay(1); /* allow a working UART time to re-assert THRE */
1833 iir = serial_in(up, UART_IIR);
1834 serial_out(up, UART_IER, 0);
1835
1836 spin_unlock_irqrestore(&up->port.lock, flags);
1837
1838 /*
1839 * If the interrupt is not reasserted, setup a timer to
1840 * kick the UART on a regular basis.
1841 */
1842 if (iir & UART_IIR_NO_INT) {
1843 pr_debug("ttyS%d - using backup timer\n", port->line);
1844 up->timer.function = serial8250_backup_timeout;
1845 up->timer.data = (unsigned long)up;
1846 mod_timer(&up->timer, jiffies +
1847 poll_timeout(up->port.timeout) + HZ/5);
1848 }
1849 }
1850
Linus Torvalds1da177e2005-04-16 15:20:36 -07001851 /*
1852 * If the "interrupt" for this port doesn't correspond with any
1853 * hardware interrupt, we use a timer-based system. The original
1854 * driver used to do this with IRQ0.
1855 */
1856 if (!is_real_interrupt(up->port.irq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001857 up->timer.data = (unsigned long)up;
Alex Williamson40b36da2007-02-14 00:33:04 -08001858 mod_timer(&up->timer, jiffies + poll_timeout(up->port.timeout));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001859 } else {
1860 retval = serial_link_irq_chain(up);
1861 if (retval)
1862 return retval;
1863 }
1864
1865 /*
1866 * Now, initialize the UART
1867 */
1868 serial_outp(up, UART_LCR, UART_LCR_WLEN8);
1869
1870 spin_lock_irqsave(&up->port.lock, flags);
1871 if (up->port.flags & UPF_FOURPORT) {
1872 if (!is_real_interrupt(up->port.irq))
1873 up->port.mctrl |= TIOCM_OUT1;
1874 } else
1875 /*
1876 * Most PC uarts need OUT2 raised to enable interrupts.
1877 */
1878 if (is_real_interrupt(up->port.irq))
1879 up->port.mctrl |= TIOCM_OUT2;
1880
1881 serial8250_set_mctrl(&up->port, up->port.mctrl);
Russell King55d3b282005-06-23 15:05:41 +01001882
1883 /*
1884 * Do a quick test to see if we receive an
1885 * interrupt when we enable the TX irq.
1886 */
1887 serial_outp(up, UART_IER, UART_IER_THRI);
1888 lsr = serial_in(up, UART_LSR);
1889 iir = serial_in(up, UART_IIR);
1890 serial_outp(up, UART_IER, 0);
1891
1892 if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) {
Russell King67f76542005-06-23 22:26:43 +01001893 if (!(up->bugs & UART_BUG_TXEN)) {
1894 up->bugs |= UART_BUG_TXEN;
Russell King55d3b282005-06-23 15:05:41 +01001895 pr_debug("ttyS%d - enabling bad tx status workarounds\n",
1896 port->line);
1897 }
1898 } else {
Russell King67f76542005-06-23 22:26:43 +01001899 up->bugs &= ~UART_BUG_TXEN;
Russell King55d3b282005-06-23 15:05:41 +01001900 }
1901
Linus Torvalds1da177e2005-04-16 15:20:36 -07001902 spin_unlock_irqrestore(&up->port.lock, flags);
1903
1904 /*
Corey Minyardad4c2aa2007-08-22 14:01:18 -07001905 * Clear the interrupt registers again for luck, and clear the
1906 * saved flags to avoid getting false values from polling
1907 * routines or the previous session.
1908 */
1909 serial_inp(up, UART_LSR);
1910 serial_inp(up, UART_RX);
1911 serial_inp(up, UART_IIR);
1912 serial_inp(up, UART_MSR);
1913 up->lsr_saved_flags = 0;
1914 up->msr_saved_flags = 0;
1915
1916 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917 * Finally, enable interrupts. Note: Modem status interrupts
1918 * are set via set_termios(), which will be occurring imminently
1919 * anyway, so we don't enable them here.
1920 */
1921 up->ier = UART_IER_RLSI | UART_IER_RDI;
1922 serial_outp(up, UART_IER, up->ier);
1923
1924 if (up->port.flags & UPF_FOURPORT) {
1925 unsigned int icp;
1926 /*
1927 * Enable interrupts on the AST Fourport board
1928 */
1929 icp = (up->port.iobase & 0xfe0) | 0x01f;
1930 outb_p(0x80, icp);
1931 (void) inb_p(icp);
1932 }
1933
Linus Torvalds1da177e2005-04-16 15:20:36 -07001934 return 0;
1935}
1936
1937static void serial8250_shutdown(struct uart_port *port)
1938{
1939 struct uart_8250_port *up = (struct uart_8250_port *)port;
1940 unsigned long flags;
1941
1942 /*
1943 * Disable interrupts from this port
1944 */
1945 up->ier = 0;
1946 serial_outp(up, UART_IER, 0);
1947
1948 spin_lock_irqsave(&up->port.lock, flags);
1949 if (up->port.flags & UPF_FOURPORT) {
1950 /* reset interrupts on the AST Fourport board */
1951 inb((up->port.iobase & 0xfe0) | 0x1f);
1952 up->port.mctrl |= TIOCM_OUT1;
1953 } else
1954 up->port.mctrl &= ~TIOCM_OUT2;
1955
1956 serial8250_set_mctrl(&up->port, up->port.mctrl);
1957 spin_unlock_irqrestore(&up->port.lock, flags);
1958
1959 /*
1960 * Disable break condition and FIFOs
1961 */
1962 serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
1963 serial8250_clear_fifos(up);
1964
1965#ifdef CONFIG_SERIAL_8250_RSA
1966 /*
1967 * Reset the RSA board back to 115kbps compat mode.
1968 */
1969 disable_rsa(up);
1970#endif
1971
1972 /*
1973 * Read data port to reset things, and then unlink from
1974 * the IRQ chain.
1975 */
1976 (void) serial_in(up, UART_RX);
1977
Alex Williamson40b36da2007-02-14 00:33:04 -08001978 del_timer_sync(&up->timer);
1979 up->timer.function = serial8250_timeout;
1980 if (is_real_interrupt(up->port.irq))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001981 serial_unlink_irq_chain(up);
1982}
1983
1984static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud)
1985{
1986 unsigned int quot;
1987
1988 /*
1989 * Handle magic divisors for baud rates above baud_base on
1990 * SMSC SuperIO chips.
1991 */
1992 if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
1993 baud == (port->uartclk/4))
1994 quot = 0x8001;
1995 else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
1996 baud == (port->uartclk/8))
1997 quot = 0x8002;
1998 else
1999 quot = uart_get_divisor(port, baud);
2000
2001 return quot;
2002}
2003
2004static void
Alan Cox606d0992006-12-08 02:38:45 -08002005serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
2006 struct ktermios *old)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002007{
2008 struct uart_8250_port *up = (struct uart_8250_port *)port;
2009 unsigned char cval, fcr = 0;
2010 unsigned long flags;
2011 unsigned int baud, quot;
2012
2013 switch (termios->c_cflag & CSIZE) {
2014 case CS5:
Russell King0a8b80c52005-06-24 19:48:22 +01002015 cval = UART_LCR_WLEN5;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002016 break;
2017 case CS6:
Russell King0a8b80c52005-06-24 19:48:22 +01002018 cval = UART_LCR_WLEN6;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002019 break;
2020 case CS7:
Russell King0a8b80c52005-06-24 19:48:22 +01002021 cval = UART_LCR_WLEN7;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002022 break;
2023 default:
2024 case CS8:
Russell King0a8b80c52005-06-24 19:48:22 +01002025 cval = UART_LCR_WLEN8;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002026 break;
2027 }
2028
2029 if (termios->c_cflag & CSTOPB)
Russell King0a8b80c52005-06-24 19:48:22 +01002030 cval |= UART_LCR_STOP;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002031 if (termios->c_cflag & PARENB)
2032 cval |= UART_LCR_PARITY;
2033 if (!(termios->c_cflag & PARODD))
2034 cval |= UART_LCR_EPAR;
2035#ifdef CMSPAR
2036 if (termios->c_cflag & CMSPAR)
2037 cval |= UART_LCR_SPAR;
2038#endif
2039
2040 /*
2041 * Ask the core to calculate the divisor for us.
2042 */
Thomas Koellerbd71c182007-05-06 14:48:47 -07002043 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002044 quot = serial8250_get_divisor(port, baud);
2045
2046 /*
Russell King4ba5e352005-06-23 10:43:04 +01002047 * Oxford Semi 952 rev B workaround
Linus Torvalds1da177e2005-04-16 15:20:36 -07002048 */
Russell King4ba5e352005-06-23 10:43:04 +01002049 if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002050 quot ++;
2051
2052 if (up->capabilities & UART_CAP_FIFO && up->port.fifosize > 1) {
2053 if (baud < 2400)
2054 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
2055 else
2056 fcr = uart_config[up->port.type].fcr;
2057 }
2058
2059 /*
2060 * MCR-based auto flow control. When AFE is enabled, RTS will be
2061 * deasserted when the receive FIFO contains more characters than
2062 * the trigger, or the MCR RTS bit is cleared. In the case where
2063 * the remote UART is not using CTS auto flow control, we must
2064 * have sufficient FIFO entries for the latency of the remote
2065 * UART to respond. IOW, at least 32 bytes of FIFO.
2066 */
2067 if (up->capabilities & UART_CAP_AFE && up->port.fifosize >= 32) {
2068 up->mcr &= ~UART_MCR_AFE;
2069 if (termios->c_cflag & CRTSCTS)
2070 up->mcr |= UART_MCR_AFE;
2071 }
2072
2073 /*
2074 * Ok, we're now changing the port state. Do it with
2075 * interrupts disabled.
2076 */
2077 spin_lock_irqsave(&up->port.lock, flags);
2078
2079 /*
2080 * Update the per-port timeout.
2081 */
2082 uart_update_timeout(port, termios->c_cflag, baud);
2083
2084 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
2085 if (termios->c_iflag & INPCK)
2086 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
2087 if (termios->c_iflag & (BRKINT | PARMRK))
2088 up->port.read_status_mask |= UART_LSR_BI;
2089
2090 /*
2091 * Characteres to ignore
2092 */
2093 up->port.ignore_status_mask = 0;
2094 if (termios->c_iflag & IGNPAR)
2095 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
2096 if (termios->c_iflag & IGNBRK) {
2097 up->port.ignore_status_mask |= UART_LSR_BI;
2098 /*
2099 * If we're ignoring parity and break indicators,
2100 * ignore overruns too (for real raw support).
2101 */
2102 if (termios->c_iflag & IGNPAR)
2103 up->port.ignore_status_mask |= UART_LSR_OE;
2104 }
2105
2106 /*
2107 * ignore all characters if CREAD is not set
2108 */
2109 if ((termios->c_cflag & CREAD) == 0)
2110 up->port.ignore_status_mask |= UART_LSR_DR;
2111
2112 /*
2113 * CTS flow control flag and modem status interrupts
2114 */
2115 up->ier &= ~UART_IER_MSI;
Pantelis Antoniou21c614a2005-11-06 09:07:03 +00002116 if (!(up->bugs & UART_BUG_NOMSR) &&
2117 UART_ENABLE_MS(&up->port, termios->c_cflag))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002118 up->ier |= UART_IER_MSI;
2119 if (up->capabilities & UART_CAP_UUE)
2120 up->ier |= UART_IER_UUE | UART_IER_RTOIE;
2121
2122 serial_out(up, UART_IER, up->ier);
2123
2124 if (up->capabilities & UART_CAP_EFR) {
2125 unsigned char efr = 0;
2126 /*
2127 * TI16C752/Startech hardware flow control. FIXME:
2128 * - TI16C752 requires control thresholds to be set.
2129 * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled.
2130 */
2131 if (termios->c_cflag & CRTSCTS)
2132 efr |= UART_EFR_CTS;
2133
2134 serial_outp(up, UART_LCR, 0xBF);
2135 serial_outp(up, UART_EFR, efr);
2136 }
2137
Jonathan McDowell255341c2006-08-14 23:05:32 -07002138#ifdef CONFIG_ARCH_OMAP15XX
2139 /* Workaround to enable 115200 baud on OMAP1510 internal ports */
2140 if (cpu_is_omap1510() && is_omap_port((unsigned int)up->port.membase)) {
2141 if (baud == 115200) {
2142 quot = 1;
2143 serial_out(up, UART_OMAP_OSC_12M_SEL, 1);
2144 } else
2145 serial_out(up, UART_OMAP_OSC_12M_SEL, 0);
2146 }
2147#endif
2148
Linus Torvalds1da177e2005-04-16 15:20:36 -07002149 if (up->capabilities & UART_NATSEMI) {
2150 /* Switch to bank 2 not bank 1, to avoid resetting EXCR2 */
2151 serial_outp(up, UART_LCR, 0xe0);
2152 } else {
2153 serial_outp(up, UART_LCR, cval | UART_LCR_DLAB);/* set DLAB */
2154 }
2155
Jon Anders Haugumb32b19b2006-04-30 11:20:56 +01002156 serial_dl_write(up, quot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002157
2158 /*
2159 * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR
2160 * is written without DLAB set, this mode will be disabled.
2161 */
2162 if (up->port.type == PORT_16750)
2163 serial_outp(up, UART_FCR, fcr);
2164
2165 serial_outp(up, UART_LCR, cval); /* reset DLAB */
2166 up->lcr = cval; /* Save LCR */
2167 if (up->port.type != PORT_16750) {
2168 if (fcr & UART_FCR_ENABLE_FIFO) {
2169 /* emulated UARTs (Lucent Venus 167x) need two steps */
2170 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
2171 }
2172 serial_outp(up, UART_FCR, fcr); /* set fcr */
2173 }
2174 serial8250_set_mctrl(&up->port, up->port.mctrl);
2175 spin_unlock_irqrestore(&up->port.lock, flags);
2176}
2177
2178static void
2179serial8250_pm(struct uart_port *port, unsigned int state,
2180 unsigned int oldstate)
2181{
2182 struct uart_8250_port *p = (struct uart_8250_port *)port;
2183
2184 serial8250_set_sleep(p, state != 0);
2185
2186 if (p->pm)
2187 p->pm(port, state, oldstate);
2188}
2189
2190/*
2191 * Resource handling.
2192 */
2193static int serial8250_request_std_resource(struct uart_8250_port *up)
2194{
2195 unsigned int size = 8 << up->port.regshift;
2196 int ret = 0;
2197
2198 switch (up->port.iotype) {
Sergei Shtylyov85835f42006-04-30 11:15:58 +01002199 case UPIO_AU:
2200 size = 0x100000;
2201 /* fall thru */
Sergei Shtylyov0b30d662006-09-09 22:23:56 +04002202 case UPIO_TSI:
2203 case UPIO_MEM32:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002204 case UPIO_MEM:
Marc St-Jeanbeab6972007-05-06 14:48:45 -07002205 case UPIO_DWAPB:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002206 if (!up->port.mapbase)
2207 break;
2208
2209 if (!request_mem_region(up->port.mapbase, size, "serial")) {
2210 ret = -EBUSY;
2211 break;
2212 }
2213
2214 if (up->port.flags & UPF_IOREMAP) {
2215 up->port.membase = ioremap(up->port.mapbase, size);
2216 if (!up->port.membase) {
2217 release_mem_region(up->port.mapbase, size);
2218 ret = -ENOMEM;
2219 }
2220 }
2221 break;
2222
2223 case UPIO_HUB6:
2224 case UPIO_PORT:
2225 if (!request_region(up->port.iobase, size, "serial"))
2226 ret = -EBUSY;
2227 break;
2228 }
2229 return ret;
2230}
2231
2232static void serial8250_release_std_resource(struct uart_8250_port *up)
2233{
2234 unsigned int size = 8 << up->port.regshift;
2235
2236 switch (up->port.iotype) {
Sergei Shtylyov85835f42006-04-30 11:15:58 +01002237 case UPIO_AU:
2238 size = 0x100000;
2239 /* fall thru */
Sergei Shtylyov0b30d662006-09-09 22:23:56 +04002240 case UPIO_TSI:
2241 case UPIO_MEM32:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002242 case UPIO_MEM:
Marc St-Jeanbeab6972007-05-06 14:48:45 -07002243 case UPIO_DWAPB:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002244 if (!up->port.mapbase)
2245 break;
2246
2247 if (up->port.flags & UPF_IOREMAP) {
2248 iounmap(up->port.membase);
2249 up->port.membase = NULL;
2250 }
2251
2252 release_mem_region(up->port.mapbase, size);
2253 break;
2254
2255 case UPIO_HUB6:
2256 case UPIO_PORT:
2257 release_region(up->port.iobase, size);
2258 break;
2259 }
2260}
2261
2262static int serial8250_request_rsa_resource(struct uart_8250_port *up)
2263{
2264 unsigned long start = UART_RSA_BASE << up->port.regshift;
2265 unsigned int size = 8 << up->port.regshift;
Sergei Shtylyov0b30d662006-09-09 22:23:56 +04002266 int ret = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002267
2268 switch (up->port.iotype) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002269 case UPIO_HUB6:
2270 case UPIO_PORT:
2271 start += up->port.iobase;
Sergei Shtylyov0b30d662006-09-09 22:23:56 +04002272 if (request_region(start, size, "serial-rsa"))
2273 ret = 0;
2274 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002275 ret = -EBUSY;
2276 break;
2277 }
2278
2279 return ret;
2280}
2281
2282static void serial8250_release_rsa_resource(struct uart_8250_port *up)
2283{
2284 unsigned long offset = UART_RSA_BASE << up->port.regshift;
2285 unsigned int size = 8 << up->port.regshift;
2286
2287 switch (up->port.iotype) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002288 case UPIO_HUB6:
2289 case UPIO_PORT:
2290 release_region(up->port.iobase + offset, size);
2291 break;
2292 }
2293}
2294
2295static void serial8250_release_port(struct uart_port *port)
2296{
2297 struct uart_8250_port *up = (struct uart_8250_port *)port;
2298
2299 serial8250_release_std_resource(up);
2300 if (up->port.type == PORT_RSA)
2301 serial8250_release_rsa_resource(up);
2302}
2303
2304static int serial8250_request_port(struct uart_port *port)
2305{
2306 struct uart_8250_port *up = (struct uart_8250_port *)port;
2307 int ret = 0;
2308
2309 ret = serial8250_request_std_resource(up);
2310 if (ret == 0 && up->port.type == PORT_RSA) {
2311 ret = serial8250_request_rsa_resource(up);
2312 if (ret < 0)
2313 serial8250_release_std_resource(up);
2314 }
2315
2316 return ret;
2317}
2318
2319static void serial8250_config_port(struct uart_port *port, int flags)
2320{
2321 struct uart_8250_port *up = (struct uart_8250_port *)port;
2322 int probeflags = PROBE_ANY;
2323 int ret;
2324
2325 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002326 * Find the region that we can probe for. This in turn
2327 * tells us whether we can probe for the type of port.
2328 */
2329 ret = serial8250_request_std_resource(up);
2330 if (ret < 0)
2331 return;
2332
2333 ret = serial8250_request_rsa_resource(up);
2334 if (ret < 0)
2335 probeflags &= ~PROBE_RSA;
2336
2337 if (flags & UART_CONFIG_TYPE)
2338 autoconfig(up, probeflags);
2339 if (up->port.type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
2340 autoconfig_irq(up);
2341
2342 if (up->port.type != PORT_RSA && probeflags & PROBE_RSA)
2343 serial8250_release_rsa_resource(up);
2344 if (up->port.type == PORT_UNKNOWN)
2345 serial8250_release_std_resource(up);
2346}
2347
2348static int
2349serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
2350{
2351 if (ser->irq >= NR_IRQS || ser->irq < 0 ||
2352 ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
2353 ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
2354 ser->type == PORT_STARTECH)
2355 return -EINVAL;
2356 return 0;
2357}
2358
2359static const char *
2360serial8250_type(struct uart_port *port)
2361{
2362 int type = port->type;
2363
2364 if (type >= ARRAY_SIZE(uart_config))
2365 type = 0;
2366 return uart_config[type].name;
2367}
2368
2369static struct uart_ops serial8250_pops = {
2370 .tx_empty = serial8250_tx_empty,
2371 .set_mctrl = serial8250_set_mctrl,
2372 .get_mctrl = serial8250_get_mctrl,
2373 .stop_tx = serial8250_stop_tx,
2374 .start_tx = serial8250_start_tx,
2375 .stop_rx = serial8250_stop_rx,
2376 .enable_ms = serial8250_enable_ms,
2377 .break_ctl = serial8250_break_ctl,
2378 .startup = serial8250_startup,
2379 .shutdown = serial8250_shutdown,
2380 .set_termios = serial8250_set_termios,
2381 .pm = serial8250_pm,
2382 .type = serial8250_type,
2383 .release_port = serial8250_release_port,
2384 .request_port = serial8250_request_port,
2385 .config_port = serial8250_config_port,
2386 .verify_port = serial8250_verify_port,
2387};
2388
2389static struct uart_8250_port serial8250_ports[UART_NR];
2390
2391static void __init serial8250_isa_init_ports(void)
2392{
2393 struct uart_8250_port *up;
2394 static int first = 1;
2395 int i;
2396
2397 if (!first)
2398 return;
2399 first = 0;
2400
Dave Jonesa61c2d72006-01-07 23:18:19 +00002401 for (i = 0; i < nr_uarts; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002402 struct uart_8250_port *up = &serial8250_ports[i];
2403
2404 up->port.line = i;
2405 spin_lock_init(&up->port.lock);
2406
2407 init_timer(&up->timer);
2408 up->timer.function = serial8250_timeout;
2409
2410 /*
2411 * ALPHA_KLUDGE_MCR needs to be killed.
2412 */
2413 up->mcr_mask = ~ALPHA_KLUDGE_MCR;
2414 up->mcr_force = ALPHA_KLUDGE_MCR;
2415
2416 up->port.ops = &serial8250_pops;
2417 }
2418
Russell King44454bc2005-06-30 22:41:22 +01002419 for (i = 0, up = serial8250_ports;
Dave Jonesa61c2d72006-01-07 23:18:19 +00002420 i < ARRAY_SIZE(old_serial_port) && i < nr_uarts;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002421 i++, up++) {
2422 up->port.iobase = old_serial_port[i].port;
2423 up->port.irq = irq_canonicalize(old_serial_port[i].irq);
2424 up->port.uartclk = old_serial_port[i].baud_base * 16;
2425 up->port.flags = old_serial_port[i].flags;
2426 up->port.hub6 = old_serial_port[i].hub6;
2427 up->port.membase = old_serial_port[i].iomem_base;
2428 up->port.iotype = old_serial_port[i].io_type;
2429 up->port.regshift = old_serial_port[i].iomem_reg_shift;
2430 if (share_irqs)
2431 up->port.flags |= UPF_SHARE_IRQ;
2432 }
2433}
2434
2435static void __init
2436serial8250_register_ports(struct uart_driver *drv, struct device *dev)
2437{
2438 int i;
2439
2440 serial8250_isa_init_ports();
2441
Dave Jonesa61c2d72006-01-07 23:18:19 +00002442 for (i = 0; i < nr_uarts; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002443 struct uart_8250_port *up = &serial8250_ports[i];
2444
2445 up->port.dev = dev;
2446 uart_add_one_port(drv, &up->port);
2447 }
2448}
2449
2450#ifdef CONFIG_SERIAL_8250_CONSOLE
2451
Russell Kingd3587882006-03-20 20:00:09 +00002452static void serial8250_console_putchar(struct uart_port *port, int ch)
2453{
2454 struct uart_8250_port *up = (struct uart_8250_port *)port;
2455
2456 wait_for_xmitr(up, UART_LSR_THRE);
2457 serial_out(up, UART_TX, ch);
2458}
2459
Linus Torvalds1da177e2005-04-16 15:20:36 -07002460/*
2461 * Print a string to the serial port trying not to disturb
2462 * any possible real use of the port...
2463 *
2464 * The console_lock must be held when we get here.
2465 */
2466static void
2467serial8250_console_write(struct console *co, const char *s, unsigned int count)
2468{
2469 struct uart_8250_port *up = &serial8250_ports[co->index];
Russell Kingd8a5a8d2006-05-02 16:04:29 +01002470 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002471 unsigned int ier;
Russell Kingd8a5a8d2006-05-02 16:04:29 +01002472 int locked = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002473
Andrew Morton78512ec2005-11-07 00:59:13 -08002474 touch_nmi_watchdog();
2475
Andrew Morton68aa2c02006-06-30 02:29:59 -07002476 local_irq_save(flags);
2477 if (up->port.sysrq) {
2478 /* serial8250_handle_port() already took the lock */
2479 locked = 0;
2480 } else if (oops_in_progress) {
2481 locked = spin_trylock(&up->port.lock);
Russell Kingd8a5a8d2006-05-02 16:04:29 +01002482 } else
Andrew Morton68aa2c02006-06-30 02:29:59 -07002483 spin_lock(&up->port.lock);
Russell Kingd8a5a8d2006-05-02 16:04:29 +01002484
Linus Torvalds1da177e2005-04-16 15:20:36 -07002485 /*
Ralf Baechledc7bf132006-02-15 09:59:47 +00002486 * First save the IER then disable the interrupts
Linus Torvalds1da177e2005-04-16 15:20:36 -07002487 */
2488 ier = serial_in(up, UART_IER);
2489
2490 if (up->capabilities & UART_CAP_UUE)
2491 serial_out(up, UART_IER, UART_IER_UUE);
2492 else
2493 serial_out(up, UART_IER, 0);
2494
Russell Kingd3587882006-03-20 20:00:09 +00002495 uart_console_write(&up->port, s, count, serial8250_console_putchar);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002496
2497 /*
2498 * Finally, wait for transmitter to become empty
2499 * and restore the IER
2500 */
Alan Coxf91a3712006-01-21 14:59:12 +00002501 wait_for_xmitr(up, BOTH_EMPTY);
Russell Kinga88d75b2006-04-30 11:30:15 +01002502 serial_out(up, UART_IER, ier);
Russell Kingd8a5a8d2006-05-02 16:04:29 +01002503
Corey Minyardad4c2aa2007-08-22 14:01:18 -07002504 /*
2505 * The receive handling will happen properly because the
2506 * receive ready bit will still be set; it is not cleared
2507 * on read. However, modem control will not, we must
2508 * call it if we have saved something in the saved flags
2509 * while processing with interrupts off.
2510 */
2511 if (up->msr_saved_flags)
2512 check_modem_status(up);
2513
Russell Kingd8a5a8d2006-05-02 16:04:29 +01002514 if (locked)
Andrew Morton68aa2c02006-06-30 02:29:59 -07002515 spin_unlock(&up->port.lock);
2516 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002517}
2518
Vivek Goyal118c0ac2007-01-11 01:52:44 +01002519static int __init serial8250_console_setup(struct console *co, char *options)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002520{
2521 struct uart_port *port;
2522 int baud = 9600;
2523 int bits = 8;
2524 int parity = 'n';
2525 int flow = 'n';
2526
2527 /*
2528 * Check whether an invalid uart number has been specified, and
2529 * if so, search for the first available port that does have
2530 * console support.
2531 */
Dave Jonesa61c2d72006-01-07 23:18:19 +00002532 if (co->index >= nr_uarts)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002533 co->index = 0;
2534 port = &serial8250_ports[co->index].port;
2535 if (!port->iobase && !port->membase)
2536 return -ENODEV;
2537
2538 if (options)
2539 uart_parse_options(options, &baud, &parity, &bits, &flow);
2540
2541 return uart_set_options(port, co, baud, parity, bits, flow);
2542}
2543
Daniel Ritzb6b1d872007-08-03 16:07:43 +02002544static int serial8250_console_early_setup(void)
Yinghai Lu18a8bd92007-07-15 23:37:59 -07002545{
2546 return serial8250_find_port_for_earlycon();
2547}
2548
Linus Torvalds1da177e2005-04-16 15:20:36 -07002549static struct uart_driver serial8250_reg;
2550static struct console serial8250_console = {
2551 .name = "ttyS",
2552 .write = serial8250_console_write,
2553 .device = uart_console_device,
2554 .setup = serial8250_console_setup,
Yinghai Lu18a8bd92007-07-15 23:37:59 -07002555 .early_setup = serial8250_console_early_setup,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002556 .flags = CON_PRINTBUFFER,
2557 .index = -1,
2558 .data = &serial8250_reg,
2559};
2560
2561static int __init serial8250_console_init(void)
2562{
2563 serial8250_isa_init_ports();
2564 register_console(&serial8250_console);
2565 return 0;
2566}
2567console_initcall(serial8250_console_init);
2568
Yinghai Lu18a8bd92007-07-15 23:37:59 -07002569int serial8250_find_port(struct uart_port *p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002570{
2571 int line;
2572 struct uart_port *port;
2573
Dave Jonesa61c2d72006-01-07 23:18:19 +00002574 for (line = 0; line < nr_uarts; line++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002575 port = &serial8250_ports[line].port;
Russell King50aec3b52006-01-04 18:13:03 +00002576 if (uart_match_port(p, port))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002577 return line;
2578 }
2579 return -ENODEV;
2580}
2581
Linus Torvalds1da177e2005-04-16 15:20:36 -07002582#define SERIAL8250_CONSOLE &serial8250_console
2583#else
2584#define SERIAL8250_CONSOLE NULL
2585#endif
2586
2587static struct uart_driver serial8250_reg = {
2588 .owner = THIS_MODULE,
2589 .driver_name = "serial",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002590 .dev_name = "ttyS",
2591 .major = TTY_MAJOR,
2592 .minor = 64,
2593 .nr = UART_NR,
2594 .cons = SERIAL8250_CONSOLE,
2595};
2596
Russell Kingd856c662006-02-23 10:22:13 +00002597/*
2598 * early_serial_setup - early registration for 8250 ports
2599 *
2600 * Setup an 8250 port structure prior to console initialisation. Use
2601 * after console initialisation will cause undefined behaviour.
2602 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002603int __init early_serial_setup(struct uart_port *port)
2604{
2605 if (port->line >= ARRAY_SIZE(serial8250_ports))
2606 return -ENODEV;
2607
2608 serial8250_isa_init_ports();
2609 serial8250_ports[port->line].port = *port;
2610 serial8250_ports[port->line].port.ops = &serial8250_pops;
2611 return 0;
2612}
2613
2614/**
2615 * serial8250_suspend_port - suspend one serial port
2616 * @line: serial line number
Linus Torvalds1da177e2005-04-16 15:20:36 -07002617 *
2618 * Suspend one serial port.
2619 */
2620void serial8250_suspend_port(int line)
2621{
2622 uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port);
2623}
2624
2625/**
2626 * serial8250_resume_port - resume one serial port
2627 * @line: serial line number
Linus Torvalds1da177e2005-04-16 15:20:36 -07002628 *
2629 * Resume one serial port.
2630 */
2631void serial8250_resume_port(int line)
2632{
David Woodhouseb5b82df2007-05-17 14:27:39 +08002633 struct uart_8250_port *up = &serial8250_ports[line];
2634
2635 if (up->capabilities & UART_NATSEMI) {
2636 unsigned char tmp;
2637
2638 /* Ensure it's still in high speed mode */
2639 serial_outp(up, UART_LCR, 0xE0);
2640
2641 tmp = serial_in(up, 0x04); /* EXCR2 */
2642 tmp &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
2643 tmp |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
2644 serial_outp(up, 0x04, tmp);
2645
2646 serial_outp(up, UART_LCR, 0);
2647 }
2648 uart_resume_port(&serial8250_reg, &up->port);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002649}
2650
2651/*
2652 * Register a set of serial devices attached to a platform device. The
2653 * list is terminated with a zero flags entry, which means we expect
2654 * all entries to have at least UPF_BOOT_AUTOCONF set.
2655 */
Russell King3ae5eae2005-11-09 22:32:44 +00002656static int __devinit serial8250_probe(struct platform_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002657{
Russell King3ae5eae2005-11-09 22:32:44 +00002658 struct plat_serial8250_port *p = dev->dev.platform_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002659 struct uart_port port;
Russell Kingec9f47c2005-06-27 11:12:54 +01002660 int ret, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002661
2662 memset(&port, 0, sizeof(struct uart_port));
2663
Russell Kingec9f47c2005-06-27 11:12:54 +01002664 for (i = 0; p && p->flags != 0; p++, i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002665 port.iobase = p->iobase;
2666 port.membase = p->membase;
2667 port.irq = p->irq;
2668 port.uartclk = p->uartclk;
2669 port.regshift = p->regshift;
2670 port.iotype = p->iotype;
2671 port.flags = p->flags;
2672 port.mapbase = p->mapbase;
Russell Kingec9f47c2005-06-27 11:12:54 +01002673 port.hub6 = p->hub6;
Russell King3ae5eae2005-11-09 22:32:44 +00002674 port.dev = &dev->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002675 if (share_irqs)
2676 port.flags |= UPF_SHARE_IRQ;
Russell Kingec9f47c2005-06-27 11:12:54 +01002677 ret = serial8250_register_port(&port);
2678 if (ret < 0) {
Russell King3ae5eae2005-11-09 22:32:44 +00002679 dev_err(&dev->dev, "unable to register port at index %d "
Josh Boyer4f640ef2007-07-23 18:43:44 -07002680 "(IO%lx MEM%llx IRQ%d): %d\n", i,
2681 p->iobase, (unsigned long long)p->mapbase,
2682 p->irq, ret);
Russell Kingec9f47c2005-06-27 11:12:54 +01002683 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002684 }
2685 return 0;
2686}
2687
2688/*
2689 * Remove serial ports registered against a platform device.
2690 */
Russell King3ae5eae2005-11-09 22:32:44 +00002691static int __devexit serial8250_remove(struct platform_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002692{
2693 int i;
2694
Dave Jonesa61c2d72006-01-07 23:18:19 +00002695 for (i = 0; i < nr_uarts; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002696 struct uart_8250_port *up = &serial8250_ports[i];
2697
Russell King3ae5eae2005-11-09 22:32:44 +00002698 if (up->port.dev == &dev->dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002699 serial8250_unregister_port(i);
2700 }
2701 return 0;
2702}
2703
Russell King3ae5eae2005-11-09 22:32:44 +00002704static int serial8250_suspend(struct platform_device *dev, pm_message_t state)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002705{
2706 int i;
2707
Linus Torvalds1da177e2005-04-16 15:20:36 -07002708 for (i = 0; i < UART_NR; i++) {
2709 struct uart_8250_port *up = &serial8250_ports[i];
2710
Russell King3ae5eae2005-11-09 22:32:44 +00002711 if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002712 uart_suspend_port(&serial8250_reg, &up->port);
2713 }
2714
2715 return 0;
2716}
2717
Russell King3ae5eae2005-11-09 22:32:44 +00002718static int serial8250_resume(struct platform_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002719{
2720 int i;
2721
Linus Torvalds1da177e2005-04-16 15:20:36 -07002722 for (i = 0; i < UART_NR; i++) {
2723 struct uart_8250_port *up = &serial8250_ports[i];
2724
Russell King3ae5eae2005-11-09 22:32:44 +00002725 if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev)
David Woodhouseb5b82df2007-05-17 14:27:39 +08002726 serial8250_resume_port(i);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002727 }
2728
2729 return 0;
2730}
2731
Russell King3ae5eae2005-11-09 22:32:44 +00002732static struct platform_driver serial8250_isa_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002733 .probe = serial8250_probe,
2734 .remove = __devexit_p(serial8250_remove),
2735 .suspend = serial8250_suspend,
2736 .resume = serial8250_resume,
Russell King3ae5eae2005-11-09 22:32:44 +00002737 .driver = {
2738 .name = "serial8250",
Dmitry Torokhov7493a312006-01-13 22:06:43 +00002739 .owner = THIS_MODULE,
Russell King3ae5eae2005-11-09 22:32:44 +00002740 },
Linus Torvalds1da177e2005-04-16 15:20:36 -07002741};
2742
2743/*
2744 * This "device" covers _all_ ISA 8250-compatible serial devices listed
2745 * in the table in include/asm/serial.h
2746 */
2747static struct platform_device *serial8250_isa_devs;
2748
2749/*
2750 * serial8250_register_port and serial8250_unregister_port allows for
2751 * 16x50 serial ports to be configured at run-time, to support PCMCIA
2752 * modems and PCI multiport cards.
2753 */
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002754static DEFINE_MUTEX(serial_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002755
2756static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *port)
2757{
2758 int i;
2759
2760 /*
2761 * First, find a port entry which matches.
2762 */
Dave Jonesa61c2d72006-01-07 23:18:19 +00002763 for (i = 0; i < nr_uarts; i++)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002764 if (uart_match_port(&serial8250_ports[i].port, port))
2765 return &serial8250_ports[i];
2766
2767 /*
2768 * We didn't find a matching entry, so look for the first
2769 * free entry. We look for one which hasn't been previously
2770 * used (indicated by zero iobase).
2771 */
Dave Jonesa61c2d72006-01-07 23:18:19 +00002772 for (i = 0; i < nr_uarts; i++)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002773 if (serial8250_ports[i].port.type == PORT_UNKNOWN &&
2774 serial8250_ports[i].port.iobase == 0)
2775 return &serial8250_ports[i];
2776
2777 /*
2778 * That also failed. Last resort is to find any entry which
2779 * doesn't have a real port associated with it.
2780 */
Dave Jonesa61c2d72006-01-07 23:18:19 +00002781 for (i = 0; i < nr_uarts; i++)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002782 if (serial8250_ports[i].port.type == PORT_UNKNOWN)
2783 return &serial8250_ports[i];
2784
2785 return NULL;
2786}
2787
2788/**
2789 * serial8250_register_port - register a serial port
2790 * @port: serial port template
2791 *
2792 * Configure the serial port specified by the request. If the
2793 * port exists and is in use, it is hung up and unregistered
2794 * first.
2795 *
2796 * The port is then probed and if necessary the IRQ is autodetected
2797 * If this fails an error is returned.
2798 *
2799 * On success the port is ready to use and the line number is returned.
2800 */
2801int serial8250_register_port(struct uart_port *port)
2802{
2803 struct uart_8250_port *uart;
2804 int ret = -ENOSPC;
2805
2806 if (port->uartclk == 0)
2807 return -EINVAL;
2808
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002809 mutex_lock(&serial_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002810
2811 uart = serial8250_find_match_or_unused(port);
2812 if (uart) {
2813 uart_remove_one_port(&serial8250_reg, &uart->port);
2814
2815 uart->port.iobase = port->iobase;
2816 uart->port.membase = port->membase;
2817 uart->port.irq = port->irq;
2818 uart->port.uartclk = port->uartclk;
2819 uart->port.fifosize = port->fifosize;
2820 uart->port.regshift = port->regshift;
2821 uart->port.iotype = port->iotype;
2822 uart->port.flags = port->flags | UPF_BOOT_AUTOCONF;
2823 uart->port.mapbase = port->mapbase;
2824 if (port->dev)
2825 uart->port.dev = port->dev;
2826
2827 ret = uart_add_one_port(&serial8250_reg, &uart->port);
2828 if (ret == 0)
2829 ret = uart->port.line;
2830 }
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002831 mutex_unlock(&serial_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002832
2833 return ret;
2834}
2835EXPORT_SYMBOL(serial8250_register_port);
2836
2837/**
2838 * serial8250_unregister_port - remove a 16x50 serial port at runtime
2839 * @line: serial line number
2840 *
2841 * Remove one serial port. This may not be called from interrupt
2842 * context. We hand the port back to the our control.
2843 */
2844void serial8250_unregister_port(int line)
2845{
2846 struct uart_8250_port *uart = &serial8250_ports[line];
2847
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002848 mutex_lock(&serial_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002849 uart_remove_one_port(&serial8250_reg, &uart->port);
2850 if (serial8250_isa_devs) {
2851 uart->port.flags &= ~UPF_BOOT_AUTOCONF;
2852 uart->port.type = PORT_UNKNOWN;
2853 uart->port.dev = &serial8250_isa_devs->dev;
2854 uart_add_one_port(&serial8250_reg, &uart->port);
2855 } else {
2856 uart->port.dev = NULL;
2857 }
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002858 mutex_unlock(&serial_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002859}
2860EXPORT_SYMBOL(serial8250_unregister_port);
2861
2862static int __init serial8250_init(void)
2863{
2864 int ret, i;
2865
Dave Jonesa61c2d72006-01-07 23:18:19 +00002866 if (nr_uarts > UART_NR)
2867 nr_uarts = UART_NR;
2868
Linus Torvalds1da177e2005-04-16 15:20:36 -07002869 printk(KERN_INFO "Serial: 8250/16550 driver $Revision: 1.90 $ "
Dave Jonesa61c2d72006-01-07 23:18:19 +00002870 "%d ports, IRQ sharing %sabled\n", nr_uarts,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002871 share_irqs ? "en" : "dis");
2872
2873 for (i = 0; i < NR_IRQS; i++)
2874 spin_lock_init(&irq_lists[i].lock);
2875
2876 ret = uart_register_driver(&serial8250_reg);
2877 if (ret)
2878 goto out;
2879
Dmitry Torokhov7493a312006-01-13 22:06:43 +00002880 serial8250_isa_devs = platform_device_alloc("serial8250",
2881 PLAT8250_DEV_LEGACY);
2882 if (!serial8250_isa_devs) {
2883 ret = -ENOMEM;
Russell Kingbc965a72006-01-18 09:54:29 +00002884 goto unreg_uart_drv;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002885 }
2886
Dmitry Torokhov7493a312006-01-13 22:06:43 +00002887 ret = platform_device_add(serial8250_isa_devs);
2888 if (ret)
2889 goto put_dev;
2890
Linus Torvalds1da177e2005-04-16 15:20:36 -07002891 serial8250_register_ports(&serial8250_reg, &serial8250_isa_devs->dev);
2892
Russell Kingbc965a72006-01-18 09:54:29 +00002893 ret = platform_driver_register(&serial8250_isa_driver);
2894 if (ret == 0)
2895 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002896
Russell Kingbc965a72006-01-18 09:54:29 +00002897 platform_device_del(serial8250_isa_devs);
Dmitry Torokhov7493a312006-01-13 22:06:43 +00002898 put_dev:
2899 platform_device_put(serial8250_isa_devs);
Dmitry Torokhov7493a312006-01-13 22:06:43 +00002900 unreg_uart_drv:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002901 uart_unregister_driver(&serial8250_reg);
2902 out:
2903 return ret;
2904}
2905
2906static void __exit serial8250_exit(void)
2907{
2908 struct platform_device *isa_dev = serial8250_isa_devs;
2909
2910 /*
2911 * This tells serial8250_unregister_port() not to re-register
2912 * the ports (thereby making serial8250_isa_driver permanently
2913 * in use.)
2914 */
2915 serial8250_isa_devs = NULL;
2916
Russell King3ae5eae2005-11-09 22:32:44 +00002917 platform_driver_unregister(&serial8250_isa_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002918 platform_device_unregister(isa_dev);
2919
2920 uart_unregister_driver(&serial8250_reg);
2921}
2922
2923module_init(serial8250_init);
2924module_exit(serial8250_exit);
2925
2926EXPORT_SYMBOL(serial8250_suspend_port);
2927EXPORT_SYMBOL(serial8250_resume_port);
2928
2929MODULE_LICENSE("GPL");
2930MODULE_DESCRIPTION("Generic 8250/16x50 serial driver $Revision: 1.90 $");
2931
2932module_param(share_irqs, uint, 0644);
2933MODULE_PARM_DESC(share_irqs, "Share IRQs with other non-8250/16x50 devices"
2934 " (unsafe)");
2935
Dave Jonesa61c2d72006-01-07 23:18:19 +00002936module_param(nr_uarts, uint, 0644);
2937MODULE_PARM_DESC(nr_uarts, "Maximum number of UARTs supported. (1-" __MODULE_STRING(CONFIG_SERIAL_8250_NR_UARTS) ")");
2938
Linus Torvalds1da177e2005-04-16 15:20:36 -07002939#ifdef CONFIG_SERIAL_8250_RSA
2940module_param_array(probe_rsa, ulong, &probe_rsa_count, 0444);
2941MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA");
2942#endif
2943MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR);