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b6830f6d PH |
1 | /* |
2 | * Base port operations for 8250/16550-type serial ports | |
3 | * | |
4 | * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. | |
5 | * Split from 8250_core.c, Copyright (C) 2001 Russell King. | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * A note about mapbase / membase | |
13 | * | |
14 | * mapbase is the physical address of the IO port. | |
15 | * membase is an 'ioremapped' cookie. | |
16 | */ | |
17 | ||
18 | #if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) | |
19 | #define SUPPORT_SYSRQ | |
20 | #endif | |
21 | ||
22 | #include <linux/module.h> | |
23 | #include <linux/moduleparam.h> | |
24 | #include <linux/ioport.h> | |
25 | #include <linux/init.h> | |
26 | #include <linux/console.h> | |
27 | #include <linux/sysrq.h> | |
28 | #include <linux/delay.h> | |
29 | #include <linux/platform_device.h> | |
30 | #include <linux/tty.h> | |
31 | #include <linux/ratelimit.h> | |
32 | #include <linux/tty_flip.h> | |
33 | #include <linux/serial.h> | |
34 | #include <linux/serial_8250.h> | |
35 | #include <linux/nmi.h> | |
36 | #include <linux/mutex.h> | |
37 | #include <linux/slab.h> | |
38 | #include <linux/uaccess.h> | |
39 | #include <linux/pm_runtime.h> | |
e490c914 | 40 | #include <linux/timer.h> |
b6830f6d PH |
41 | |
42 | #include <asm/io.h> | |
43 | #include <asm/irq.h> | |
44 | ||
45 | #include "8250.h" | |
46 | ||
47 | /* | |
48 | * Debugging. | |
49 | */ | |
50 | #if 0 | |
51 | #define DEBUG_AUTOCONF(fmt...) printk(fmt) | |
52 | #else | |
53 | #define DEBUG_AUTOCONF(fmt...) do { } while (0) | |
54 | #endif | |
55 | ||
6d7c157f | 56 | #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) |
b6830f6d PH |
57 | |
58 | /* | |
59 | * Here we define the default xmit fifo size used for each type of UART. | |
60 | */ | |
61 | static const struct serial8250_config uart_config[] = { | |
62 | [PORT_UNKNOWN] = { | |
63 | .name = "unknown", | |
64 | .fifo_size = 1, | |
65 | .tx_loadsz = 1, | |
66 | }, | |
67 | [PORT_8250] = { | |
68 | .name = "8250", | |
69 | .fifo_size = 1, | |
70 | .tx_loadsz = 1, | |
71 | }, | |
72 | [PORT_16450] = { | |
73 | .name = "16450", | |
74 | .fifo_size = 1, | |
75 | .tx_loadsz = 1, | |
76 | }, | |
77 | [PORT_16550] = { | |
78 | .name = "16550", | |
79 | .fifo_size = 1, | |
80 | .tx_loadsz = 1, | |
81 | }, | |
82 | [PORT_16550A] = { | |
83 | .name = "16550A", | |
84 | .fifo_size = 16, | |
85 | .tx_loadsz = 16, | |
86 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
87 | .rxtrig_bytes = {1, 4, 8, 14}, | |
88 | .flags = UART_CAP_FIFO, | |
89 | }, | |
90 | [PORT_CIRRUS] = { | |
91 | .name = "Cirrus", | |
92 | .fifo_size = 1, | |
93 | .tx_loadsz = 1, | |
94 | }, | |
95 | [PORT_16650] = { | |
96 | .name = "ST16650", | |
97 | .fifo_size = 1, | |
98 | .tx_loadsz = 1, | |
99 | .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, | |
100 | }, | |
101 | [PORT_16650V2] = { | |
102 | .name = "ST16650V2", | |
103 | .fifo_size = 32, | |
104 | .tx_loadsz = 16, | |
105 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | | |
106 | UART_FCR_T_TRIG_00, | |
107 | .rxtrig_bytes = {8, 16, 24, 28}, | |
108 | .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, | |
109 | }, | |
110 | [PORT_16750] = { | |
111 | .name = "TI16750", | |
112 | .fifo_size = 64, | |
113 | .tx_loadsz = 64, | |
114 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 | | |
115 | UART_FCR7_64BYTE, | |
116 | .rxtrig_bytes = {1, 16, 32, 56}, | |
117 | .flags = UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE, | |
118 | }, | |
119 | [PORT_STARTECH] = { | |
120 | .name = "Startech", | |
121 | .fifo_size = 1, | |
122 | .tx_loadsz = 1, | |
123 | }, | |
124 | [PORT_16C950] = { | |
125 | .name = "16C950/954", | |
126 | .fifo_size = 128, | |
127 | .tx_loadsz = 128, | |
128 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
129 | /* UART_CAP_EFR breaks billionon CF bluetooth card. */ | |
130 | .flags = UART_CAP_FIFO | UART_CAP_SLEEP, | |
131 | }, | |
132 | [PORT_16654] = { | |
133 | .name = "ST16654", | |
134 | .fifo_size = 64, | |
135 | .tx_loadsz = 32, | |
136 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | | |
137 | UART_FCR_T_TRIG_10, | |
138 | .rxtrig_bytes = {8, 16, 56, 60}, | |
139 | .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, | |
140 | }, | |
141 | [PORT_16850] = { | |
142 | .name = "XR16850", | |
143 | .fifo_size = 128, | |
144 | .tx_loadsz = 128, | |
145 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
146 | .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, | |
147 | }, | |
148 | [PORT_RSA] = { | |
149 | .name = "RSA", | |
150 | .fifo_size = 2048, | |
151 | .tx_loadsz = 2048, | |
152 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11, | |
153 | .flags = UART_CAP_FIFO, | |
154 | }, | |
155 | [PORT_NS16550A] = { | |
156 | .name = "NS16550A", | |
157 | .fifo_size = 16, | |
158 | .tx_loadsz = 16, | |
159 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
160 | .flags = UART_CAP_FIFO | UART_NATSEMI, | |
161 | }, | |
162 | [PORT_XSCALE] = { | |
163 | .name = "XScale", | |
164 | .fifo_size = 32, | |
165 | .tx_loadsz = 32, | |
166 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
167 | .flags = UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE, | |
168 | }, | |
169 | [PORT_OCTEON] = { | |
170 | .name = "OCTEON", | |
171 | .fifo_size = 64, | |
172 | .tx_loadsz = 64, | |
173 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
174 | .flags = UART_CAP_FIFO, | |
175 | }, | |
176 | [PORT_AR7] = { | |
177 | .name = "AR7", | |
178 | .fifo_size = 16, | |
179 | .tx_loadsz = 16, | |
180 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00, | |
181 | .flags = UART_CAP_FIFO | UART_CAP_AFE, | |
182 | }, | |
183 | [PORT_U6_16550A] = { | |
184 | .name = "U6_16550A", | |
185 | .fifo_size = 64, | |
186 | .tx_loadsz = 64, | |
187 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
188 | .flags = UART_CAP_FIFO | UART_CAP_AFE, | |
189 | }, | |
190 | [PORT_TEGRA] = { | |
191 | .name = "Tegra", | |
192 | .fifo_size = 32, | |
193 | .tx_loadsz = 8, | |
194 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | | |
195 | UART_FCR_T_TRIG_01, | |
196 | .rxtrig_bytes = {1, 4, 8, 14}, | |
197 | .flags = UART_CAP_FIFO | UART_CAP_RTOIE, | |
198 | }, | |
199 | [PORT_XR17D15X] = { | |
200 | .name = "XR17D15X", | |
201 | .fifo_size = 64, | |
202 | .tx_loadsz = 64, | |
203 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
204 | .flags = UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR | | |
205 | UART_CAP_SLEEP, | |
206 | }, | |
207 | [PORT_XR17V35X] = { | |
208 | .name = "XR17V35X", | |
209 | .fifo_size = 256, | |
210 | .tx_loadsz = 256, | |
211 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11 | | |
212 | UART_FCR_T_TRIG_11, | |
213 | .flags = UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR | | |
214 | UART_CAP_SLEEP, | |
215 | }, | |
216 | [PORT_LPC3220] = { | |
217 | .name = "LPC3220", | |
218 | .fifo_size = 64, | |
219 | .tx_loadsz = 32, | |
220 | .fcr = UART_FCR_DMA_SELECT | UART_FCR_ENABLE_FIFO | | |
221 | UART_FCR_R_TRIG_00 | UART_FCR_T_TRIG_00, | |
222 | .flags = UART_CAP_FIFO, | |
223 | }, | |
224 | [PORT_BRCM_TRUMANAGE] = { | |
225 | .name = "TruManage", | |
226 | .fifo_size = 1, | |
227 | .tx_loadsz = 1024, | |
228 | .flags = UART_CAP_HFIFO, | |
229 | }, | |
230 | [PORT_8250_CIR] = { | |
231 | .name = "CIR port" | |
232 | }, | |
233 | [PORT_ALTR_16550_F32] = { | |
234 | .name = "Altera 16550 FIFO32", | |
235 | .fifo_size = 32, | |
236 | .tx_loadsz = 32, | |
237 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
238 | .flags = UART_CAP_FIFO | UART_CAP_AFE, | |
239 | }, | |
240 | [PORT_ALTR_16550_F64] = { | |
241 | .name = "Altera 16550 FIFO64", | |
242 | .fifo_size = 64, | |
243 | .tx_loadsz = 64, | |
244 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
245 | .flags = UART_CAP_FIFO | UART_CAP_AFE, | |
246 | }, | |
247 | [PORT_ALTR_16550_F128] = { | |
248 | .name = "Altera 16550 FIFO128", | |
249 | .fifo_size = 128, | |
250 | .tx_loadsz = 128, | |
251 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
252 | .flags = UART_CAP_FIFO | UART_CAP_AFE, | |
253 | }, | |
740dc2de AW |
254 | /* |
255 | * tx_loadsz is set to 63-bytes instead of 64-bytes to implement | |
256 | * workaround of errata A-008006 which states that tx_loadsz should | |
257 | * be configured less than Maximum supported fifo bytes. | |
258 | */ | |
b6830f6d PH |
259 | [PORT_16550A_FSL64] = { |
260 | .name = "16550A_FSL64", | |
261 | .fifo_size = 64, | |
262 | .tx_loadsz = 63, | |
263 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 | | |
264 | UART_FCR7_64BYTE, | |
265 | .flags = UART_CAP_FIFO, | |
266 | }, | |
3c5a0357 MR |
267 | [PORT_RT2880] = { |
268 | .name = "Palmchip BK-3103", | |
269 | .fifo_size = 16, | |
270 | .tx_loadsz = 16, | |
271 | .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, | |
272 | .rxtrig_bytes = {1, 4, 8, 14}, | |
273 | .flags = UART_CAP_FIFO, | |
274 | }, | |
b6830f6d PH |
275 | }; |
276 | ||
277 | /* Uart divisor latch read */ | |
278 | static int default_serial_dl_read(struct uart_8250_port *up) | |
279 | { | |
280 | return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8; | |
281 | } | |
282 | ||
283 | /* Uart divisor latch write */ | |
284 | static void default_serial_dl_write(struct uart_8250_port *up, int value) | |
285 | { | |
286 | serial_out(up, UART_DLL, value & 0xff); | |
287 | serial_out(up, UART_DLM, value >> 8 & 0xff); | |
288 | } | |
289 | ||
9b2256c8 | 290 | #ifdef CONFIG_SERIAL_8250_RT288X |
b6830f6d PH |
291 | |
292 | /* Au1x00/RT288x UART hardware has a weird register layout */ | |
293 | static const s8 au_io_in_map[8] = { | |
294 | 0, /* UART_RX */ | |
295 | 2, /* UART_IER */ | |
296 | 3, /* UART_IIR */ | |
297 | 5, /* UART_LCR */ | |
298 | 6, /* UART_MCR */ | |
299 | 7, /* UART_LSR */ | |
300 | 8, /* UART_MSR */ | |
301 | -1, /* UART_SCR (unmapped) */ | |
302 | }; | |
303 | ||
304 | static const s8 au_io_out_map[8] = { | |
305 | 1, /* UART_TX */ | |
306 | 2, /* UART_IER */ | |
307 | 4, /* UART_FCR */ | |
308 | 5, /* UART_LCR */ | |
309 | 6, /* UART_MCR */ | |
310 | -1, /* UART_LSR (unmapped) */ | |
311 | -1, /* UART_MSR (unmapped) */ | |
312 | -1, /* UART_SCR (unmapped) */ | |
313 | }; | |
314 | ||
315 | static unsigned int au_serial_in(struct uart_port *p, int offset) | |
316 | { | |
317 | if (offset >= ARRAY_SIZE(au_io_in_map)) | |
318 | return UINT_MAX; | |
319 | offset = au_io_in_map[offset]; | |
320 | if (offset < 0) | |
321 | return UINT_MAX; | |
322 | return __raw_readl(p->membase + (offset << p->regshift)); | |
323 | } | |
324 | ||
325 | static void au_serial_out(struct uart_port *p, int offset, int value) | |
326 | { | |
327 | if (offset >= ARRAY_SIZE(au_io_out_map)) | |
328 | return; | |
329 | offset = au_io_out_map[offset]; | |
330 | if (offset < 0) | |
331 | return; | |
332 | __raw_writel(value, p->membase + (offset << p->regshift)); | |
333 | } | |
334 | ||
335 | /* Au1x00 haven't got a standard divisor latch */ | |
336 | static int au_serial_dl_read(struct uart_8250_port *up) | |
337 | { | |
338 | return __raw_readl(up->port.membase + 0x28); | |
339 | } | |
340 | ||
341 | static void au_serial_dl_write(struct uart_8250_port *up, int value) | |
342 | { | |
343 | __raw_writel(value, up->port.membase + 0x28); | |
344 | } | |
345 | ||
346 | #endif | |
347 | ||
348 | static unsigned int hub6_serial_in(struct uart_port *p, int offset) | |
349 | { | |
350 | offset = offset << p->regshift; | |
351 | outb(p->hub6 - 1 + offset, p->iobase); | |
352 | return inb(p->iobase + 1); | |
353 | } | |
354 | ||
355 | static void hub6_serial_out(struct uart_port *p, int offset, int value) | |
356 | { | |
357 | offset = offset << p->regshift; | |
358 | outb(p->hub6 - 1 + offset, p->iobase); | |
359 | outb(value, p->iobase + 1); | |
360 | } | |
361 | ||
362 | static unsigned int mem_serial_in(struct uart_port *p, int offset) | |
363 | { | |
364 | offset = offset << p->regshift; | |
365 | return readb(p->membase + offset); | |
366 | } | |
367 | ||
368 | static void mem_serial_out(struct uart_port *p, int offset, int value) | |
369 | { | |
370 | offset = offset << p->regshift; | |
371 | writeb(value, p->membase + offset); | |
372 | } | |
373 | ||
bd94c407 MY |
374 | static void mem16_serial_out(struct uart_port *p, int offset, int value) |
375 | { | |
376 | offset = offset << p->regshift; | |
377 | writew(value, p->membase + offset); | |
378 | } | |
379 | ||
380 | static unsigned int mem16_serial_in(struct uart_port *p, int offset) | |
381 | { | |
382 | offset = offset << p->regshift; | |
383 | return readw(p->membase + offset); | |
384 | } | |
385 | ||
b6830f6d PH |
386 | static void mem32_serial_out(struct uart_port *p, int offset, int value) |
387 | { | |
388 | offset = offset << p->regshift; | |
389 | writel(value, p->membase + offset); | |
390 | } | |
391 | ||
392 | static unsigned int mem32_serial_in(struct uart_port *p, int offset) | |
393 | { | |
394 | offset = offset << p->regshift; | |
395 | return readl(p->membase + offset); | |
396 | } | |
397 | ||
398 | static void mem32be_serial_out(struct uart_port *p, int offset, int value) | |
399 | { | |
400 | offset = offset << p->regshift; | |
401 | iowrite32be(value, p->membase + offset); | |
402 | } | |
403 | ||
404 | static unsigned int mem32be_serial_in(struct uart_port *p, int offset) | |
405 | { | |
406 | offset = offset << p->regshift; | |
407 | return ioread32be(p->membase + offset); | |
408 | } | |
409 | ||
410 | static unsigned int io_serial_in(struct uart_port *p, int offset) | |
411 | { | |
412 | offset = offset << p->regshift; | |
413 | return inb(p->iobase + offset); | |
414 | } | |
415 | ||
416 | static void io_serial_out(struct uart_port *p, int offset, int value) | |
417 | { | |
418 | offset = offset << p->regshift; | |
419 | outb(value, p->iobase + offset); | |
420 | } | |
421 | ||
422 | static int serial8250_default_handle_irq(struct uart_port *port); | |
423 | static int exar_handle_irq(struct uart_port *port); | |
424 | ||
425 | static void set_io_from_upio(struct uart_port *p) | |
426 | { | |
427 | struct uart_8250_port *up = up_to_u8250p(p); | |
428 | ||
429 | up->dl_read = default_serial_dl_read; | |
430 | up->dl_write = default_serial_dl_write; | |
431 | ||
432 | switch (p->iotype) { | |
433 | case UPIO_HUB6: | |
434 | p->serial_in = hub6_serial_in; | |
435 | p->serial_out = hub6_serial_out; | |
436 | break; | |
437 | ||
438 | case UPIO_MEM: | |
439 | p->serial_in = mem_serial_in; | |
440 | p->serial_out = mem_serial_out; | |
441 | break; | |
442 | ||
bd94c407 MY |
443 | case UPIO_MEM16: |
444 | p->serial_in = mem16_serial_in; | |
445 | p->serial_out = mem16_serial_out; | |
446 | break; | |
447 | ||
b6830f6d PH |
448 | case UPIO_MEM32: |
449 | p->serial_in = mem32_serial_in; | |
450 | p->serial_out = mem32_serial_out; | |
451 | break; | |
452 | ||
453 | case UPIO_MEM32BE: | |
454 | p->serial_in = mem32be_serial_in; | |
455 | p->serial_out = mem32be_serial_out; | |
456 | break; | |
457 | ||
9b2256c8 | 458 | #ifdef CONFIG_SERIAL_8250_RT288X |
b6830f6d PH |
459 | case UPIO_AU: |
460 | p->serial_in = au_serial_in; | |
461 | p->serial_out = au_serial_out; | |
462 | up->dl_read = au_serial_dl_read; | |
463 | up->dl_write = au_serial_dl_write; | |
464 | break; | |
465 | #endif | |
466 | ||
467 | default: | |
468 | p->serial_in = io_serial_in; | |
469 | p->serial_out = io_serial_out; | |
470 | break; | |
471 | } | |
472 | /* Remember loaded iotype */ | |
473 | up->cur_iotype = p->iotype; | |
474 | p->handle_irq = serial8250_default_handle_irq; | |
475 | } | |
476 | ||
477 | static void | |
478 | serial_port_out_sync(struct uart_port *p, int offset, int value) | |
479 | { | |
480 | switch (p->iotype) { | |
481 | case UPIO_MEM: | |
bd94c407 | 482 | case UPIO_MEM16: |
b6830f6d PH |
483 | case UPIO_MEM32: |
484 | case UPIO_MEM32BE: | |
485 | case UPIO_AU: | |
486 | p->serial_out(p, offset, value); | |
487 | p->serial_in(p, UART_LCR); /* safe, no side-effects */ | |
488 | break; | |
489 | default: | |
490 | p->serial_out(p, offset, value); | |
491 | } | |
492 | } | |
493 | ||
494 | /* | |
495 | * For the 16C950 | |
496 | */ | |
497 | static void serial_icr_write(struct uart_8250_port *up, int offset, int value) | |
498 | { | |
499 | serial_out(up, UART_SCR, offset); | |
500 | serial_out(up, UART_ICR, value); | |
501 | } | |
502 | ||
503 | static unsigned int serial_icr_read(struct uart_8250_port *up, int offset) | |
504 | { | |
505 | unsigned int value; | |
506 | ||
507 | serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD); | |
508 | serial_out(up, UART_SCR, offset); | |
509 | value = serial_in(up, UART_ICR); | |
510 | serial_icr_write(up, UART_ACR, up->acr); | |
511 | ||
512 | return value; | |
513 | } | |
514 | ||
515 | /* | |
516 | * FIFO support. | |
517 | */ | |
518 | static void serial8250_clear_fifos(struct uart_8250_port *p) | |
519 | { | |
520 | if (p->capabilities & UART_CAP_FIFO) { | |
521 | serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO); | |
522 | serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO | | |
523 | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); | |
524 | serial_out(p, UART_FCR, 0); | |
525 | } | |
526 | } | |
527 | ||
e490c914 MK |
528 | static inline void serial8250_em485_rts_after_send(struct uart_8250_port *p) |
529 | { | |
530 | unsigned char mcr = serial_in(p, UART_MCR); | |
531 | ||
532 | if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND) | |
533 | mcr |= UART_MCR_RTS; | |
534 | else | |
535 | mcr &= ~UART_MCR_RTS; | |
536 | serial_out(p, UART_MCR, mcr); | |
537 | } | |
538 | ||
539 | static void serial8250_em485_handle_start_tx(unsigned long arg); | |
540 | static void serial8250_em485_handle_stop_tx(unsigned long arg); | |
541 | ||
b6830f6d PH |
542 | void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p) |
543 | { | |
544 | serial8250_clear_fifos(p); | |
545 | serial_out(p, UART_FCR, p->fcr); | |
546 | } | |
547 | EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos); | |
548 | ||
549 | void serial8250_rpm_get(struct uart_8250_port *p) | |
550 | { | |
551 | if (!(p->capabilities & UART_CAP_RPM)) | |
552 | return; | |
553 | pm_runtime_get_sync(p->port.dev); | |
554 | } | |
555 | EXPORT_SYMBOL_GPL(serial8250_rpm_get); | |
556 | ||
557 | void serial8250_rpm_put(struct uart_8250_port *p) | |
558 | { | |
559 | if (!(p->capabilities & UART_CAP_RPM)) | |
560 | return; | |
561 | pm_runtime_mark_last_busy(p->port.dev); | |
562 | pm_runtime_put_autosuspend(p->port.dev); | |
563 | } | |
564 | EXPORT_SYMBOL_GPL(serial8250_rpm_put); | |
565 | ||
e490c914 MK |
566 | /** |
567 | * serial8250_em485_init() - put uart_8250_port into rs485 emulating | |
568 | * @p: uart_8250_port port instance | |
569 | * | |
570 | * The function is used to start rs485 software emulating on the | |
571 | * &struct uart_8250_port* @p. Namely, RTS is switched before/after | |
572 | * transmission. The function is idempotent, so it is safe to call it | |
573 | * multiple times. | |
574 | * | |
575 | * The caller MUST enable interrupt on empty shift register before | |
576 | * calling serial8250_em485_init(). This interrupt is not a part of | |
577 | * 8250 standard, but implementation defined. | |
578 | * | |
579 | * The function is supposed to be called from .rs485_config callback | |
580 | * or from any other callback protected with p->port.lock spinlock. | |
581 | * | |
582 | * See also serial8250_em485_destroy() | |
583 | * | |
584 | * Return 0 - success, -errno - otherwise | |
585 | */ | |
586 | int serial8250_em485_init(struct uart_8250_port *p) | |
587 | { | |
588 | if (p->em485 != NULL) | |
589 | return 0; | |
590 | ||
b18a183e | 591 | p->em485 = kmalloc(sizeof(struct uart_8250_em485), GFP_ATOMIC); |
e490c914 MK |
592 | if (p->em485 == NULL) |
593 | return -ENOMEM; | |
594 | ||
595 | setup_timer(&p->em485->stop_tx_timer, | |
596 | serial8250_em485_handle_stop_tx, (unsigned long)p); | |
597 | setup_timer(&p->em485->start_tx_timer, | |
598 | serial8250_em485_handle_start_tx, (unsigned long)p); | |
599 | p->em485->active_timer = NULL; | |
600 | ||
601 | serial8250_em485_rts_after_send(p); | |
602 | ||
603 | return 0; | |
604 | } | |
605 | EXPORT_SYMBOL_GPL(serial8250_em485_init); | |
606 | ||
607 | /** | |
608 | * serial8250_em485_destroy() - put uart_8250_port into normal state | |
609 | * @p: uart_8250_port port instance | |
610 | * | |
611 | * The function is used to stop rs485 software emulating on the | |
612 | * &struct uart_8250_port* @p. The function is idempotent, so it is safe to | |
613 | * call it multiple times. | |
614 | * | |
615 | * The function is supposed to be called from .rs485_config callback | |
616 | * or from any other callback protected with p->port.lock spinlock. | |
617 | * | |
618 | * See also serial8250_em485_init() | |
619 | */ | |
620 | void serial8250_em485_destroy(struct uart_8250_port *p) | |
621 | { | |
622 | if (p->em485 == NULL) | |
623 | return; | |
624 | ||
625 | del_timer(&p->em485->start_tx_timer); | |
626 | del_timer(&p->em485->stop_tx_timer); | |
627 | ||
628 | kfree(p->em485); | |
629 | p->em485 = NULL; | |
630 | } | |
631 | EXPORT_SYMBOL_GPL(serial8250_em485_destroy); | |
632 | ||
b6830f6d PH |
633 | /* |
634 | * These two wrappers ensure that enable_runtime_pm_tx() can be called more than | |
635 | * once and disable_runtime_pm_tx() will still disable RPM because the fifo is | |
636 | * empty and the HW can idle again. | |
637 | */ | |
638 | static void serial8250_rpm_get_tx(struct uart_8250_port *p) | |
639 | { | |
640 | unsigned char rpm_active; | |
641 | ||
642 | if (!(p->capabilities & UART_CAP_RPM)) | |
643 | return; | |
644 | ||
645 | rpm_active = xchg(&p->rpm_tx_active, 1); | |
646 | if (rpm_active) | |
647 | return; | |
648 | pm_runtime_get_sync(p->port.dev); | |
649 | } | |
650 | ||
651 | static void serial8250_rpm_put_tx(struct uart_8250_port *p) | |
652 | { | |
653 | unsigned char rpm_active; | |
654 | ||
655 | if (!(p->capabilities & UART_CAP_RPM)) | |
656 | return; | |
657 | ||
658 | rpm_active = xchg(&p->rpm_tx_active, 0); | |
659 | if (!rpm_active) | |
660 | return; | |
661 | pm_runtime_mark_last_busy(p->port.dev); | |
662 | pm_runtime_put_autosuspend(p->port.dev); | |
663 | } | |
664 | ||
665 | /* | |
666 | * IER sleep support. UARTs which have EFRs need the "extended | |
667 | * capability" bit enabled. Note that on XR16C850s, we need to | |
668 | * reset LCR to write to IER. | |
669 | */ | |
670 | static void serial8250_set_sleep(struct uart_8250_port *p, int sleep) | |
671 | { | |
672 | unsigned char lcr = 0, efr = 0; | |
673 | /* | |
674 | * Exar UARTs have a SLEEP register that enables or disables | |
675 | * each UART to enter sleep mode separately. On the XR17V35x the | |
676 | * register is accessible to each UART at the UART_EXAR_SLEEP | |
677 | * offset but the UART channel may only write to the corresponding | |
678 | * bit. | |
679 | */ | |
680 | serial8250_rpm_get(p); | |
681 | if ((p->port.type == PORT_XR17V35X) || | |
682 | (p->port.type == PORT_XR17D15X)) { | |
683 | serial_out(p, UART_EXAR_SLEEP, sleep ? 0xff : 0); | |
684 | goto out; | |
685 | } | |
686 | ||
687 | if (p->capabilities & UART_CAP_SLEEP) { | |
688 | if (p->capabilities & UART_CAP_EFR) { | |
689 | lcr = serial_in(p, UART_LCR); | |
690 | efr = serial_in(p, UART_EFR); | |
691 | serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B); | |
692 | serial_out(p, UART_EFR, UART_EFR_ECB); | |
693 | serial_out(p, UART_LCR, 0); | |
694 | } | |
695 | serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0); | |
696 | if (p->capabilities & UART_CAP_EFR) { | |
697 | serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B); | |
698 | serial_out(p, UART_EFR, efr); | |
699 | serial_out(p, UART_LCR, lcr); | |
700 | } | |
701 | } | |
702 | out: | |
703 | serial8250_rpm_put(p); | |
704 | } | |
705 | ||
706 | #ifdef CONFIG_SERIAL_8250_RSA | |
707 | /* | |
708 | * Attempts to turn on the RSA FIFO. Returns zero on failure. | |
709 | * We set the port uart clock rate if we succeed. | |
710 | */ | |
711 | static int __enable_rsa(struct uart_8250_port *up) | |
712 | { | |
713 | unsigned char mode; | |
714 | int result; | |
715 | ||
716 | mode = serial_in(up, UART_RSA_MSR); | |
717 | result = mode & UART_RSA_MSR_FIFO; | |
718 | ||
719 | if (!result) { | |
720 | serial_out(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO); | |
721 | mode = serial_in(up, UART_RSA_MSR); | |
722 | result = mode & UART_RSA_MSR_FIFO; | |
723 | } | |
724 | ||
725 | if (result) | |
726 | up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16; | |
727 | ||
728 | return result; | |
729 | } | |
730 | ||
731 | static void enable_rsa(struct uart_8250_port *up) | |
732 | { | |
733 | if (up->port.type == PORT_RSA) { | |
734 | if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) { | |
735 | spin_lock_irq(&up->port.lock); | |
736 | __enable_rsa(up); | |
737 | spin_unlock_irq(&up->port.lock); | |
738 | } | |
739 | if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) | |
740 | serial_out(up, UART_RSA_FRR, 0); | |
741 | } | |
742 | } | |
743 | ||
744 | /* | |
745 | * Attempts to turn off the RSA FIFO. Returns zero on failure. | |
746 | * It is unknown why interrupts were disabled in here. However, | |
747 | * the caller is expected to preserve this behaviour by grabbing | |
748 | * the spinlock before calling this function. | |
749 | */ | |
750 | static void disable_rsa(struct uart_8250_port *up) | |
751 | { | |
752 | unsigned char mode; | |
753 | int result; | |
754 | ||
755 | if (up->port.type == PORT_RSA && | |
756 | up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) { | |
757 | spin_lock_irq(&up->port.lock); | |
758 | ||
759 | mode = serial_in(up, UART_RSA_MSR); | |
760 | result = !(mode & UART_RSA_MSR_FIFO); | |
761 | ||
762 | if (!result) { | |
763 | serial_out(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO); | |
764 | mode = serial_in(up, UART_RSA_MSR); | |
765 | result = !(mode & UART_RSA_MSR_FIFO); | |
766 | } | |
767 | ||
768 | if (result) | |
769 | up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16; | |
770 | spin_unlock_irq(&up->port.lock); | |
771 | } | |
772 | } | |
773 | #endif /* CONFIG_SERIAL_8250_RSA */ | |
774 | ||
775 | /* | |
776 | * This is a quickie test to see how big the FIFO is. | |
777 | * It doesn't work at all the time, more's the pity. | |
778 | */ | |
779 | static int size_fifo(struct uart_8250_port *up) | |
780 | { | |
781 | unsigned char old_fcr, old_mcr, old_lcr; | |
782 | unsigned short old_dl; | |
783 | int count; | |
784 | ||
785 | old_lcr = serial_in(up, UART_LCR); | |
786 | serial_out(up, UART_LCR, 0); | |
787 | old_fcr = serial_in(up, UART_FCR); | |
788 | old_mcr = serial_in(up, UART_MCR); | |
789 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | | |
790 | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); | |
791 | serial_out(up, UART_MCR, UART_MCR_LOOP); | |
792 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); | |
793 | old_dl = serial_dl_read(up); | |
794 | serial_dl_write(up, 0x0001); | |
795 | serial_out(up, UART_LCR, 0x03); | |
796 | for (count = 0; count < 256; count++) | |
797 | serial_out(up, UART_TX, count); | |
798 | mdelay(20);/* FIXME - schedule_timeout */ | |
799 | for (count = 0; (serial_in(up, UART_LSR) & UART_LSR_DR) && | |
800 | (count < 256); count++) | |
801 | serial_in(up, UART_RX); | |
802 | serial_out(up, UART_FCR, old_fcr); | |
803 | serial_out(up, UART_MCR, old_mcr); | |
804 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); | |
805 | serial_dl_write(up, old_dl); | |
806 | serial_out(up, UART_LCR, old_lcr); | |
807 | ||
808 | return count; | |
809 | } | |
810 | ||
811 | /* | |
812 | * Read UART ID using the divisor method - set DLL and DLM to zero | |
813 | * and the revision will be in DLL and device type in DLM. We | |
814 | * preserve the device state across this. | |
815 | */ | |
816 | static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p) | |
817 | { | |
0b41ce99 SF |
818 | unsigned char old_lcr; |
819 | unsigned int id, old_dl; | |
b6830f6d PH |
820 | |
821 | old_lcr = serial_in(p, UART_LCR); | |
822 | serial_out(p, UART_LCR, UART_LCR_CONF_MODE_A); | |
0b41ce99 SF |
823 | old_dl = serial_dl_read(p); |
824 | serial_dl_write(p, 0); | |
825 | id = serial_dl_read(p); | |
826 | serial_dl_write(p, old_dl); | |
b6830f6d | 827 | |
b6830f6d PH |
828 | serial_out(p, UART_LCR, old_lcr); |
829 | ||
830 | return id; | |
831 | } | |
832 | ||
833 | /* | |
834 | * This is a helper routine to autodetect StarTech/Exar/Oxsemi UART's. | |
835 | * When this function is called we know it is at least a StarTech | |
836 | * 16650 V2, but it might be one of several StarTech UARTs, or one of | |
837 | * its clones. (We treat the broken original StarTech 16650 V1 as a | |
838 | * 16550, and why not? Startech doesn't seem to even acknowledge its | |
839 | * existence.) | |
840 | * | |
841 | * What evil have men's minds wrought... | |
842 | */ | |
843 | static void autoconfig_has_efr(struct uart_8250_port *up) | |
844 | { | |
845 | unsigned int id1, id2, id3, rev; | |
846 | ||
847 | /* | |
848 | * Everything with an EFR has SLEEP | |
849 | */ | |
850 | up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP; | |
851 | ||
852 | /* | |
853 | * First we check to see if it's an Oxford Semiconductor UART. | |
854 | * | |
855 | * If we have to do this here because some non-National | |
856 | * Semiconductor clone chips lock up if you try writing to the | |
857 | * LSR register (which serial_icr_read does) | |
858 | */ | |
859 | ||
860 | /* | |
861 | * Check for Oxford Semiconductor 16C950. | |
862 | * | |
863 | * EFR [4] must be set else this test fails. | |
864 | * | |
865 | * This shouldn't be necessary, but Mike Hudson (Exoray@isys.ca) | |
866 | * claims that it's needed for 952 dual UART's (which are not | |
867 | * recommended for new designs). | |
868 | */ | |
869 | up->acr = 0; | |
870 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); | |
871 | serial_out(up, UART_EFR, UART_EFR_ECB); | |
872 | serial_out(up, UART_LCR, 0x00); | |
873 | id1 = serial_icr_read(up, UART_ID1); | |
874 | id2 = serial_icr_read(up, UART_ID2); | |
875 | id3 = serial_icr_read(up, UART_ID3); | |
876 | rev = serial_icr_read(up, UART_REV); | |
877 | ||
878 | DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev); | |
879 | ||
880 | if (id1 == 0x16 && id2 == 0xC9 && | |
881 | (id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) { | |
882 | up->port.type = PORT_16C950; | |
883 | ||
884 | /* | |
885 | * Enable work around for the Oxford Semiconductor 952 rev B | |
886 | * chip which causes it to seriously miscalculate baud rates | |
887 | * when DLL is 0. | |
888 | */ | |
889 | if (id3 == 0x52 && rev == 0x01) | |
890 | up->bugs |= UART_BUG_QUOT; | |
891 | return; | |
892 | } | |
893 | ||
894 | /* | |
895 | * We check for a XR16C850 by setting DLL and DLM to 0, and then | |
896 | * reading back DLL and DLM. The chip type depends on the DLM | |
897 | * value read back: | |
898 | * 0x10 - XR16C850 and the DLL contains the chip revision. | |
899 | * 0x12 - XR16C2850. | |
900 | * 0x14 - XR16C854. | |
901 | */ | |
902 | id1 = autoconfig_read_divisor_id(up); | |
903 | DEBUG_AUTOCONF("850id=%04x ", id1); | |
904 | ||
905 | id2 = id1 >> 8; | |
906 | if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) { | |
907 | up->port.type = PORT_16850; | |
908 | return; | |
909 | } | |
910 | ||
911 | /* | |
912 | * It wasn't an XR16C850. | |
913 | * | |
914 | * We distinguish between the '654 and the '650 by counting | |
915 | * how many bytes are in the FIFO. I'm using this for now, | |
916 | * since that's the technique that was sent to me in the | |
917 | * serial driver update, but I'm not convinced this works. | |
918 | * I've had problems doing this in the past. -TYT | |
919 | */ | |
920 | if (size_fifo(up) == 64) | |
921 | up->port.type = PORT_16654; | |
922 | else | |
923 | up->port.type = PORT_16650V2; | |
924 | } | |
925 | ||
926 | /* | |
927 | * We detected a chip without a FIFO. Only two fall into | |
928 | * this category - the original 8250 and the 16450. The | |
929 | * 16450 has a scratch register (accessible with LCR=0) | |
930 | */ | |
931 | static void autoconfig_8250(struct uart_8250_port *up) | |
932 | { | |
933 | unsigned char scratch, status1, status2; | |
934 | ||
935 | up->port.type = PORT_8250; | |
936 | ||
937 | scratch = serial_in(up, UART_SCR); | |
938 | serial_out(up, UART_SCR, 0xa5); | |
939 | status1 = serial_in(up, UART_SCR); | |
940 | serial_out(up, UART_SCR, 0x5a); | |
941 | status2 = serial_in(up, UART_SCR); | |
942 | serial_out(up, UART_SCR, scratch); | |
943 | ||
944 | if (status1 == 0xa5 && status2 == 0x5a) | |
945 | up->port.type = PORT_16450; | |
946 | } | |
947 | ||
948 | static int broken_efr(struct uart_8250_port *up) | |
949 | { | |
950 | /* | |
951 | * Exar ST16C2550 "A2" devices incorrectly detect as | |
952 | * having an EFR, and report an ID of 0x0201. See | |
953 | * http://linux.derkeiler.com/Mailing-Lists/Kernel/2004-11/4812.html | |
954 | */ | |
955 | if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16) | |
956 | return 1; | |
957 | ||
958 | return 0; | |
959 | } | |
960 | ||
961 | /* | |
962 | * We know that the chip has FIFOs. Does it have an EFR? The | |
963 | * EFR is located in the same register position as the IIR and | |
964 | * we know the top two bits of the IIR are currently set. The | |
965 | * EFR should contain zero. Try to read the EFR. | |
966 | */ | |
967 | static void autoconfig_16550a(struct uart_8250_port *up) | |
968 | { | |
969 | unsigned char status1, status2; | |
970 | unsigned int iersave; | |
971 | ||
972 | up->port.type = PORT_16550A; | |
973 | up->capabilities |= UART_CAP_FIFO; | |
974 | ||
975 | /* | |
976 | * XR17V35x UARTs have an extra divisor register, DLD | |
977 | * that gets enabled with when DLAB is set which will | |
978 | * cause the device to incorrectly match and assign | |
979 | * port type to PORT_16650. The EFR for this UART is | |
980 | * found at offset 0x09. Instead check the Deice ID (DVID) | |
981 | * register for a 2, 4 or 8 port UART. | |
982 | */ | |
983 | if (up->port.flags & UPF_EXAR_EFR) { | |
984 | status1 = serial_in(up, UART_EXAR_DVID); | |
985 | if (status1 == 0x82 || status1 == 0x84 || status1 == 0x88) { | |
986 | DEBUG_AUTOCONF("Exar XR17V35x "); | |
987 | up->port.type = PORT_XR17V35X; | |
988 | up->capabilities |= UART_CAP_AFE | UART_CAP_EFR | | |
989 | UART_CAP_SLEEP; | |
990 | ||
991 | return; | |
992 | } | |
993 | ||
994 | } | |
995 | ||
996 | /* | |
997 | * Check for presence of the EFR when DLAB is set. | |
998 | * Only ST16C650V1 UARTs pass this test. | |
999 | */ | |
1000 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); | |
1001 | if (serial_in(up, UART_EFR) == 0) { | |
1002 | serial_out(up, UART_EFR, 0xA8); | |
1003 | if (serial_in(up, UART_EFR) != 0) { | |
1004 | DEBUG_AUTOCONF("EFRv1 "); | |
1005 | up->port.type = PORT_16650; | |
1006 | up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP; | |
1007 | } else { | |
1008 | serial_out(up, UART_LCR, 0); | |
1009 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | | |
1010 | UART_FCR7_64BYTE); | |
1011 | status1 = serial_in(up, UART_IIR) >> 5; | |
1012 | serial_out(up, UART_FCR, 0); | |
1013 | serial_out(up, UART_LCR, 0); | |
1014 | ||
1015 | if (status1 == 7) | |
1016 | up->port.type = PORT_16550A_FSL64; | |
1017 | else | |
1018 | DEBUG_AUTOCONF("Motorola 8xxx DUART "); | |
1019 | } | |
1020 | serial_out(up, UART_EFR, 0); | |
1021 | return; | |
1022 | } | |
1023 | ||
1024 | /* | |
1025 | * Maybe it requires 0xbf to be written to the LCR. | |
1026 | * (other ST16C650V2 UARTs, TI16C752A, etc) | |
1027 | */ | |
1028 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); | |
1029 | if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) { | |
1030 | DEBUG_AUTOCONF("EFRv2 "); | |
1031 | autoconfig_has_efr(up); | |
1032 | return; | |
1033 | } | |
1034 | ||
1035 | /* | |
1036 | * Check for a National Semiconductor SuperIO chip. | |
1037 | * Attempt to switch to bank 2, read the value of the LOOP bit | |
1038 | * from EXCR1. Switch back to bank 0, change it in MCR. Then | |
1039 | * switch back to bank 2, read it from EXCR1 again and check | |
1040 | * it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2 | |
1041 | */ | |
1042 | serial_out(up, UART_LCR, 0); | |
1043 | status1 = serial_in(up, UART_MCR); | |
1044 | serial_out(up, UART_LCR, 0xE0); | |
1045 | status2 = serial_in(up, 0x02); /* EXCR1 */ | |
1046 | ||
1047 | if (!((status2 ^ status1) & UART_MCR_LOOP)) { | |
1048 | serial_out(up, UART_LCR, 0); | |
1049 | serial_out(up, UART_MCR, status1 ^ UART_MCR_LOOP); | |
1050 | serial_out(up, UART_LCR, 0xE0); | |
1051 | status2 = serial_in(up, 0x02); /* EXCR1 */ | |
1052 | serial_out(up, UART_LCR, 0); | |
1053 | serial_out(up, UART_MCR, status1); | |
1054 | ||
1055 | if ((status2 ^ status1) & UART_MCR_LOOP) { | |
1056 | unsigned short quot; | |
1057 | ||
1058 | serial_out(up, UART_LCR, 0xE0); | |
1059 | ||
1060 | quot = serial_dl_read(up); | |
1061 | quot <<= 3; | |
1062 | ||
1063 | if (ns16550a_goto_highspeed(up)) | |
1064 | serial_dl_write(up, quot); | |
1065 | ||
1066 | serial_out(up, UART_LCR, 0); | |
1067 | ||
1068 | up->port.uartclk = 921600*16; | |
1069 | up->port.type = PORT_NS16550A; | |
1070 | up->capabilities |= UART_NATSEMI; | |
1071 | return; | |
1072 | } | |
1073 | } | |
1074 | ||
1075 | /* | |
1076 | * No EFR. Try to detect a TI16750, which only sets bit 5 of | |
1077 | * the IIR when 64 byte FIFO mode is enabled when DLAB is set. | |
1078 | * Try setting it with and without DLAB set. Cheap clones | |
1079 | * set bit 5 without DLAB set. | |
1080 | */ | |
1081 | serial_out(up, UART_LCR, 0); | |
1082 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE); | |
1083 | status1 = serial_in(up, UART_IIR) >> 5; | |
1084 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); | |
1085 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); | |
1086 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE); | |
1087 | status2 = serial_in(up, UART_IIR) >> 5; | |
1088 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); | |
1089 | serial_out(up, UART_LCR, 0); | |
1090 | ||
1091 | DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2); | |
1092 | ||
1093 | if (status1 == 6 && status2 == 7) { | |
1094 | up->port.type = PORT_16750; | |
1095 | up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP; | |
1096 | return; | |
1097 | } | |
1098 | ||
1099 | /* | |
1100 | * Try writing and reading the UART_IER_UUE bit (b6). | |
1101 | * If it works, this is probably one of the Xscale platform's | |
1102 | * internal UARTs. | |
1103 | * We're going to explicitly set the UUE bit to 0 before | |
1104 | * trying to write and read a 1 just to make sure it's not | |
1105 | * already a 1 and maybe locked there before we even start start. | |
1106 | */ | |
1107 | iersave = serial_in(up, UART_IER); | |
1108 | serial_out(up, UART_IER, iersave & ~UART_IER_UUE); | |
1109 | if (!(serial_in(up, UART_IER) & UART_IER_UUE)) { | |
1110 | /* | |
1111 | * OK it's in a known zero state, try writing and reading | |
1112 | * without disturbing the current state of the other bits. | |
1113 | */ | |
1114 | serial_out(up, UART_IER, iersave | UART_IER_UUE); | |
1115 | if (serial_in(up, UART_IER) & UART_IER_UUE) { | |
1116 | /* | |
1117 | * It's an Xscale. | |
1118 | * We'll leave the UART_IER_UUE bit set to 1 (enabled). | |
1119 | */ | |
1120 | DEBUG_AUTOCONF("Xscale "); | |
1121 | up->port.type = PORT_XSCALE; | |
1122 | up->capabilities |= UART_CAP_UUE | UART_CAP_RTOIE; | |
1123 | return; | |
1124 | } | |
1125 | } else { | |
1126 | /* | |
1127 | * If we got here we couldn't force the IER_UUE bit to 0. | |
1128 | * Log it and continue. | |
1129 | */ | |
1130 | DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 "); | |
1131 | } | |
1132 | serial_out(up, UART_IER, iersave); | |
1133 | ||
1134 | /* | |
1135 | * Exar uarts have EFR in a weird location | |
1136 | */ | |
1137 | if (up->port.flags & UPF_EXAR_EFR) { | |
1138 | DEBUG_AUTOCONF("Exar XR17D15x "); | |
1139 | up->port.type = PORT_XR17D15X; | |
1140 | up->capabilities |= UART_CAP_AFE | UART_CAP_EFR | | |
1141 | UART_CAP_SLEEP; | |
1142 | ||
1143 | return; | |
1144 | } | |
1145 | ||
1146 | /* | |
1147 | * We distinguish between 16550A and U6 16550A by counting | |
1148 | * how many bytes are in the FIFO. | |
1149 | */ | |
1150 | if (up->port.type == PORT_16550A && size_fifo(up) == 64) { | |
1151 | up->port.type = PORT_U6_16550A; | |
1152 | up->capabilities |= UART_CAP_AFE; | |
1153 | } | |
1154 | } | |
1155 | ||
1156 | /* | |
1157 | * This routine is called by rs_init() to initialize a specific serial | |
1158 | * port. It determines what type of UART chip this serial port is | |
1159 | * using: 8250, 16450, 16550, 16550A. The important question is | |
1160 | * whether or not this UART is a 16550A or not, since this will | |
1161 | * determine whether or not we can use its FIFO features or not. | |
1162 | */ | |
1163 | static void autoconfig(struct uart_8250_port *up) | |
1164 | { | |
1165 | unsigned char status1, scratch, scratch2, scratch3; | |
1166 | unsigned char save_lcr, save_mcr; | |
1167 | struct uart_port *port = &up->port; | |
1168 | unsigned long flags; | |
1169 | unsigned int old_capabilities; | |
1170 | ||
1171 | if (!port->iobase && !port->mapbase && !port->membase) | |
1172 | return; | |
1173 | ||
1174 | DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04lx, 0x%p): ", | |
1175 | serial_index(port), port->iobase, port->membase); | |
1176 | ||
1177 | /* | |
1178 | * We really do need global IRQs disabled here - we're going to | |
1179 | * be frobbing the chips IRQ enable register to see if it exists. | |
1180 | */ | |
1181 | spin_lock_irqsave(&port->lock, flags); | |
1182 | ||
1183 | up->capabilities = 0; | |
1184 | up->bugs = 0; | |
1185 | ||
1186 | if (!(port->flags & UPF_BUGGY_UART)) { | |
1187 | /* | |
1188 | * Do a simple existence test first; if we fail this, | |
1189 | * there's no point trying anything else. | |
1190 | * | |
1191 | * 0x80 is used as a nonsense port to prevent against | |
1192 | * false positives due to ISA bus float. The | |
1193 | * assumption is that 0x80 is a non-existent port; | |
1194 | * which should be safe since include/asm/io.h also | |
1195 | * makes this assumption. | |
1196 | * | |
1197 | * Note: this is safe as long as MCR bit 4 is clear | |
1198 | * and the device is in "PC" mode. | |
1199 | */ | |
1200 | scratch = serial_in(up, UART_IER); | |
1201 | serial_out(up, UART_IER, 0); | |
1202 | #ifdef __i386__ | |
1203 | outb(0xff, 0x080); | |
1204 | #endif | |
1205 | /* | |
1206 | * Mask out IER[7:4] bits for test as some UARTs (e.g. TL | |
1207 | * 16C754B) allow only to modify them if an EFR bit is set. | |
1208 | */ | |
1209 | scratch2 = serial_in(up, UART_IER) & 0x0f; | |
1210 | serial_out(up, UART_IER, 0x0F); | |
1211 | #ifdef __i386__ | |
1212 | outb(0, 0x080); | |
1213 | #endif | |
1214 | scratch3 = serial_in(up, UART_IER) & 0x0f; | |
1215 | serial_out(up, UART_IER, scratch); | |
1216 | if (scratch2 != 0 || scratch3 != 0x0F) { | |
1217 | /* | |
1218 | * We failed; there's nothing here | |
1219 | */ | |
1220 | spin_unlock_irqrestore(&port->lock, flags); | |
1221 | DEBUG_AUTOCONF("IER test failed (%02x, %02x) ", | |
1222 | scratch2, scratch3); | |
1223 | goto out; | |
1224 | } | |
1225 | } | |
1226 | ||
1227 | save_mcr = serial_in(up, UART_MCR); | |
1228 | save_lcr = serial_in(up, UART_LCR); | |
1229 | ||
1230 | /* | |
1231 | * Check to see if a UART is really there. Certain broken | |
1232 | * internal modems based on the Rockwell chipset fail this | |
1233 | * test, because they apparently don't implement the loopback | |
1234 | * test mode. So this test is skipped on the COM 1 through | |
1235 | * COM 4 ports. This *should* be safe, since no board | |
1236 | * manufacturer would be stupid enough to design a board | |
1237 | * that conflicts with COM 1-4 --- we hope! | |
1238 | */ | |
1239 | if (!(port->flags & UPF_SKIP_TEST)) { | |
1240 | serial_out(up, UART_MCR, UART_MCR_LOOP | 0x0A); | |
1241 | status1 = serial_in(up, UART_MSR) & 0xF0; | |
1242 | serial_out(up, UART_MCR, save_mcr); | |
1243 | if (status1 != 0x90) { | |
1244 | spin_unlock_irqrestore(&port->lock, flags); | |
1245 | DEBUG_AUTOCONF("LOOP test failed (%02x) ", | |
1246 | status1); | |
1247 | goto out; | |
1248 | } | |
1249 | } | |
1250 | ||
1251 | /* | |
1252 | * We're pretty sure there's a port here. Lets find out what | |
1253 | * type of port it is. The IIR top two bits allows us to find | |
1254 | * out if it's 8250 or 16450, 16550, 16550A or later. This | |
1255 | * determines what we test for next. | |
1256 | * | |
1257 | * We also initialise the EFR (if any) to zero for later. The | |
1258 | * EFR occupies the same register location as the FCR and IIR. | |
1259 | */ | |
1260 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); | |
1261 | serial_out(up, UART_EFR, 0); | |
1262 | serial_out(up, UART_LCR, 0); | |
1263 | ||
1264 | serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); | |
1265 | scratch = serial_in(up, UART_IIR) >> 6; | |
1266 | ||
1267 | switch (scratch) { | |
1268 | case 0: | |
1269 | autoconfig_8250(up); | |
1270 | break; | |
1271 | case 1: | |
1272 | port->type = PORT_UNKNOWN; | |
1273 | break; | |
1274 | case 2: | |
1275 | port->type = PORT_16550; | |
1276 | break; | |
1277 | case 3: | |
1278 | autoconfig_16550a(up); | |
1279 | break; | |
1280 | } | |
1281 | ||
1282 | #ifdef CONFIG_SERIAL_8250_RSA | |
1283 | /* | |
1284 | * Only probe for RSA ports if we got the region. | |
1285 | */ | |
1286 | if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA && | |
1287 | __enable_rsa(up)) | |
1288 | port->type = PORT_RSA; | |
1289 | #endif | |
1290 | ||
1291 | serial_out(up, UART_LCR, save_lcr); | |
1292 | ||
1293 | port->fifosize = uart_config[up->port.type].fifo_size; | |
1294 | old_capabilities = up->capabilities; | |
1295 | up->capabilities = uart_config[port->type].flags; | |
1296 | up->tx_loadsz = uart_config[port->type].tx_loadsz; | |
1297 | ||
1298 | if (port->type == PORT_UNKNOWN) | |
1299 | goto out_lock; | |
1300 | ||
1301 | /* | |
1302 | * Reset the UART. | |
1303 | */ | |
1304 | #ifdef CONFIG_SERIAL_8250_RSA | |
1305 | if (port->type == PORT_RSA) | |
1306 | serial_out(up, UART_RSA_FRR, 0); | |
1307 | #endif | |
1308 | serial_out(up, UART_MCR, save_mcr); | |
1309 | serial8250_clear_fifos(up); | |
1310 | serial_in(up, UART_RX); | |
1311 | if (up->capabilities & UART_CAP_UUE) | |
1312 | serial_out(up, UART_IER, UART_IER_UUE); | |
1313 | else | |
1314 | serial_out(up, UART_IER, 0); | |
1315 | ||
1316 | out_lock: | |
1317 | spin_unlock_irqrestore(&port->lock, flags); | |
1318 | if (up->capabilities != old_capabilities) { | |
9f59fbf0 | 1319 | pr_warn("ttyS%d: detected caps %08x should be %08x\n", |
b6830f6d PH |
1320 | serial_index(port), old_capabilities, |
1321 | up->capabilities); | |
1322 | } | |
1323 | out: | |
1324 | DEBUG_AUTOCONF("iir=%d ", scratch); | |
1325 | DEBUG_AUTOCONF("type=%s\n", uart_config[port->type].name); | |
1326 | } | |
1327 | ||
1328 | static void autoconfig_irq(struct uart_8250_port *up) | |
1329 | { | |
1330 | struct uart_port *port = &up->port; | |
1331 | unsigned char save_mcr, save_ier; | |
1332 | unsigned char save_ICP = 0; | |
1333 | unsigned int ICP = 0; | |
1334 | unsigned long irqs; | |
1335 | int irq; | |
1336 | ||
1337 | if (port->flags & UPF_FOURPORT) { | |
1338 | ICP = (port->iobase & 0xfe0) | 0x1f; | |
1339 | save_ICP = inb_p(ICP); | |
1340 | outb_p(0x80, ICP); | |
1341 | inb_p(ICP); | |
1342 | } | |
1343 | ||
9a23a1d1 TK |
1344 | if (uart_console(port)) |
1345 | console_lock(); | |
1346 | ||
b6830f6d PH |
1347 | /* forget possible initially masked and pending IRQ */ |
1348 | probe_irq_off(probe_irq_on()); | |
1349 | save_mcr = serial_in(up, UART_MCR); | |
1350 | save_ier = serial_in(up, UART_IER); | |
1351 | serial_out(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2); | |
1352 | ||
1353 | irqs = probe_irq_on(); | |
1354 | serial_out(up, UART_MCR, 0); | |
1355 | udelay(10); | |
1356 | if (port->flags & UPF_FOURPORT) { | |
1357 | serial_out(up, UART_MCR, | |
1358 | UART_MCR_DTR | UART_MCR_RTS); | |
1359 | } else { | |
1360 | serial_out(up, UART_MCR, | |
1361 | UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2); | |
1362 | } | |
1363 | serial_out(up, UART_IER, 0x0f); /* enable all intrs */ | |
1364 | serial_in(up, UART_LSR); | |
1365 | serial_in(up, UART_RX); | |
1366 | serial_in(up, UART_IIR); | |
1367 | serial_in(up, UART_MSR); | |
1368 | serial_out(up, UART_TX, 0xFF); | |
1369 | udelay(20); | |
1370 | irq = probe_irq_off(irqs); | |
1371 | ||
1372 | serial_out(up, UART_MCR, save_mcr); | |
1373 | serial_out(up, UART_IER, save_ier); | |
1374 | ||
1375 | if (port->flags & UPF_FOURPORT) | |
1376 | outb_p(save_ICP, ICP); | |
1377 | ||
9a23a1d1 TK |
1378 | if (uart_console(port)) |
1379 | console_unlock(); | |
1380 | ||
b6830f6d PH |
1381 | port->irq = (irq > 0) ? irq : 0; |
1382 | } | |
1383 | ||
a07a70bc MK |
1384 | static void serial8250_stop_rx(struct uart_port *port) |
1385 | { | |
1386 | struct uart_8250_port *up = up_to_u8250p(port); | |
1387 | ||
1388 | serial8250_rpm_get(up); | |
1389 | ||
1390 | up->ier &= ~(UART_IER_RLSI | UART_IER_RDI); | |
1391 | up->port.read_status_mask &= ~UART_LSR_DR; | |
1392 | serial_port_out(port, UART_IER, up->ier); | |
1393 | ||
1394 | serial8250_rpm_put(up); | |
1395 | } | |
1396 | ||
e490c914 MK |
1397 | static void __do_stop_tx_rs485(struct uart_8250_port *p) |
1398 | { | |
1399 | if (!p->em485) | |
1400 | return; | |
1401 | ||
1402 | serial8250_em485_rts_after_send(p); | |
1403 | /* | |
1404 | * Empty the RX FIFO, we are not interested in anything | |
1405 | * received during the half-duplex transmission. | |
0c66940d | 1406 | * Enable previously disabled RX interrupts. |
e490c914 | 1407 | */ |
0c66940d | 1408 | if (!(p->port.rs485.flags & SER_RS485_RX_DURING_TX)) { |
e490c914 | 1409 | serial8250_clear_fifos(p); |
0c66940d YY |
1410 | |
1411 | serial8250_rpm_get(p); | |
1412 | ||
1413 | p->ier |= UART_IER_RLSI | UART_IER_RDI; | |
1414 | serial_port_out(&p->port, UART_IER, p->ier); | |
1415 | ||
1416 | serial8250_rpm_put(p); | |
1417 | } | |
e490c914 MK |
1418 | } |
1419 | ||
1420 | static void serial8250_em485_handle_stop_tx(unsigned long arg) | |
1421 | { | |
1422 | struct uart_8250_port *p = (struct uart_8250_port *)arg; | |
1423 | struct uart_8250_em485 *em485 = p->em485; | |
1424 | unsigned long flags; | |
1425 | ||
1426 | spin_lock_irqsave(&p->port.lock, flags); | |
1427 | if (em485 && | |
1428 | em485->active_timer == &em485->stop_tx_timer) { | |
1429 | __do_stop_tx_rs485(p); | |
1430 | em485->active_timer = NULL; | |
1431 | } | |
1432 | spin_unlock_irqrestore(&p->port.lock, flags); | |
1433 | } | |
1434 | ||
1435 | static void __stop_tx_rs485(struct uart_8250_port *p) | |
1436 | { | |
1437 | struct uart_8250_em485 *em485 = p->em485; | |
1438 | ||
1439 | if (!em485) | |
1440 | return; | |
1441 | ||
1442 | /* | |
1443 | * __do_stop_tx_rs485 is going to set RTS according to config | |
1444 | * AND flush RX FIFO if required. | |
1445 | */ | |
1446 | if (p->port.rs485.delay_rts_after_send > 0) { | |
1447 | em485->active_timer = &em485->stop_tx_timer; | |
1448 | mod_timer(&em485->stop_tx_timer, jiffies + | |
1449 | p->port.rs485.delay_rts_after_send * HZ / 1000); | |
1450 | } else { | |
1451 | __do_stop_tx_rs485(p); | |
1452 | } | |
1453 | } | |
1454 | ||
1455 | static inline void __do_stop_tx(struct uart_8250_port *p) | |
b6830f6d PH |
1456 | { |
1457 | if (p->ier & UART_IER_THRI) { | |
1458 | p->ier &= ~UART_IER_THRI; | |
1459 | serial_out(p, UART_IER, p->ier); | |
1460 | serial8250_rpm_put_tx(p); | |
1461 | } | |
1462 | } | |
1463 | ||
e490c914 MK |
1464 | static inline void __stop_tx(struct uart_8250_port *p) |
1465 | { | |
1466 | struct uart_8250_em485 *em485 = p->em485; | |
1467 | ||
1468 | if (em485) { | |
1469 | unsigned char lsr = serial_in(p, UART_LSR); | |
1470 | /* | |
1471 | * To provide required timeing and allow FIFO transfer, | |
1472 | * __stop_tx_rs485 must be called only when both FIFO and | |
1473 | * shift register are empty. It is for device driver to enable | |
1474 | * interrupt on TEMT. | |
1475 | */ | |
1476 | if ((lsr & BOTH_EMPTY) != BOTH_EMPTY) | |
1477 | return; | |
1478 | ||
1479 | del_timer(&em485->start_tx_timer); | |
1480 | em485->active_timer = NULL; | |
1481 | } | |
1482 | __do_stop_tx(p); | |
1483 | __stop_tx_rs485(p); | |
1484 | } | |
1485 | ||
b6830f6d PH |
1486 | static void serial8250_stop_tx(struct uart_port *port) |
1487 | { | |
1488 | struct uart_8250_port *up = up_to_u8250p(port); | |
1489 | ||
1490 | serial8250_rpm_get(up); | |
1491 | __stop_tx(up); | |
1492 | ||
1493 | /* | |
1494 | * We really want to stop the transmitter from sending. | |
1495 | */ | |
1496 | if (port->type == PORT_16C950) { | |
1497 | up->acr |= UART_ACR_TXDIS; | |
1498 | serial_icr_write(up, UART_ACR, up->acr); | |
1499 | } | |
1500 | serial8250_rpm_put(up); | |
1501 | } | |
1502 | ||
e490c914 | 1503 | static inline void __start_tx(struct uart_port *port) |
b6830f6d PH |
1504 | { |
1505 | struct uart_8250_port *up = up_to_u8250p(port); | |
1506 | ||
b6830f6d PH |
1507 | if (up->dma && !up->dma->tx_dma(up)) |
1508 | return; | |
1509 | ||
1510 | if (!(up->ier & UART_IER_THRI)) { | |
1511 | up->ier |= UART_IER_THRI; | |
1512 | serial_port_out(port, UART_IER, up->ier); | |
1513 | ||
1514 | if (up->bugs & UART_BUG_TXEN) { | |
1515 | unsigned char lsr; | |
1a33e342 | 1516 | |
b6830f6d PH |
1517 | lsr = serial_in(up, UART_LSR); |
1518 | up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS; | |
1519 | if (lsr & UART_LSR_THRE) | |
1520 | serial8250_tx_chars(up); | |
1521 | } | |
1522 | } | |
1523 | ||
1524 | /* | |
1525 | * Re-enable the transmitter if we disabled it. | |
1526 | */ | |
1527 | if (port->type == PORT_16C950 && up->acr & UART_ACR_TXDIS) { | |
1528 | up->acr &= ~UART_ACR_TXDIS; | |
1529 | serial_icr_write(up, UART_ACR, up->acr); | |
1530 | } | |
1531 | } | |
1532 | ||
e490c914 MK |
1533 | static inline void start_tx_rs485(struct uart_port *port) |
1534 | { | |
1535 | struct uart_8250_port *up = up_to_u8250p(port); | |
1536 | struct uart_8250_em485 *em485 = up->em485; | |
1537 | unsigned char mcr; | |
1538 | ||
1539 | if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX)) | |
1540 | serial8250_stop_rx(&up->port); | |
1541 | ||
1542 | del_timer(&em485->stop_tx_timer); | |
1543 | em485->active_timer = NULL; | |
1544 | ||
1545 | mcr = serial_in(up, UART_MCR); | |
1546 | if (!!(up->port.rs485.flags & SER_RS485_RTS_ON_SEND) != | |
1547 | !!(mcr & UART_MCR_RTS)) { | |
1548 | if (up->port.rs485.flags & SER_RS485_RTS_ON_SEND) | |
1549 | mcr |= UART_MCR_RTS; | |
1550 | else | |
1551 | mcr &= ~UART_MCR_RTS; | |
1552 | serial_out(up, UART_MCR, mcr); | |
1553 | ||
1554 | if (up->port.rs485.delay_rts_before_send > 0) { | |
1555 | em485->active_timer = &em485->start_tx_timer; | |
1556 | mod_timer(&em485->start_tx_timer, jiffies + | |
1557 | up->port.rs485.delay_rts_before_send * HZ / 1000); | |
1558 | return; | |
1559 | } | |
1560 | } | |
1561 | ||
1562 | __start_tx(port); | |
1563 | } | |
1564 | ||
1565 | static void serial8250_em485_handle_start_tx(unsigned long arg) | |
1566 | { | |
1567 | struct uart_8250_port *p = (struct uart_8250_port *)arg; | |
1568 | struct uart_8250_em485 *em485 = p->em485; | |
1569 | unsigned long flags; | |
1570 | ||
1571 | spin_lock_irqsave(&p->port.lock, flags); | |
1572 | if (em485 && | |
1573 | em485->active_timer == &em485->start_tx_timer) { | |
1574 | __start_tx(&p->port); | |
1575 | em485->active_timer = NULL; | |
1576 | } | |
1577 | spin_unlock_irqrestore(&p->port.lock, flags); | |
1578 | } | |
1579 | ||
1580 | static void serial8250_start_tx(struct uart_port *port) | |
1581 | { | |
1582 | struct uart_8250_port *up = up_to_u8250p(port); | |
1583 | struct uart_8250_em485 *em485 = up->em485; | |
1584 | ||
1585 | serial8250_rpm_get_tx(up); | |
1586 | ||
1587 | if (em485 && | |
1588 | em485->active_timer == &em485->start_tx_timer) | |
1589 | return; | |
1590 | ||
1591 | if (em485) | |
1592 | start_tx_rs485(port); | |
1593 | else | |
1594 | __start_tx(port); | |
1595 | } | |
1596 | ||
b6830f6d PH |
1597 | static void serial8250_throttle(struct uart_port *port) |
1598 | { | |
1599 | port->throttle(port); | |
1600 | } | |
1601 | ||
1602 | static void serial8250_unthrottle(struct uart_port *port) | |
1603 | { | |
1604 | port->unthrottle(port); | |
1605 | } | |
1606 | ||
b6830f6d PH |
1607 | static void serial8250_disable_ms(struct uart_port *port) |
1608 | { | |
013e3586 | 1609 | struct uart_8250_port *up = up_to_u8250p(port); |
b6830f6d PH |
1610 | |
1611 | /* no MSR capabilities */ | |
1612 | if (up->bugs & UART_BUG_NOMSR) | |
1613 | return; | |
1614 | ||
1615 | up->ier &= ~UART_IER_MSI; | |
1616 | serial_port_out(port, UART_IER, up->ier); | |
1617 | } | |
1618 | ||
1619 | static void serial8250_enable_ms(struct uart_port *port) | |
1620 | { | |
1621 | struct uart_8250_port *up = up_to_u8250p(port); | |
1622 | ||
1623 | /* no MSR capabilities */ | |
1624 | if (up->bugs & UART_BUG_NOMSR) | |
1625 | return; | |
1626 | ||
1627 | up->ier |= UART_IER_MSI; | |
1628 | ||
1629 | serial8250_rpm_get(up); | |
1630 | serial_port_out(port, UART_IER, up->ier); | |
1631 | serial8250_rpm_put(up); | |
1632 | } | |
1633 | ||
3f6b3ce0 PH |
1634 | static void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr) |
1635 | { | |
1636 | struct uart_port *port = &up->port; | |
1637 | unsigned char ch; | |
1638 | char flag = TTY_NORMAL; | |
1639 | ||
1640 | if (likely(lsr & UART_LSR_DR)) | |
1641 | ch = serial_in(up, UART_RX); | |
1642 | else | |
1643 | /* | |
1644 | * Intel 82571 has a Serial Over Lan device that will | |
1645 | * set UART_LSR_BI without setting UART_LSR_DR when | |
1646 | * it receives a break. To avoid reading from the | |
1647 | * receive buffer without UART_LSR_DR bit set, we | |
1648 | * just force the read character to be 0 | |
1649 | */ | |
1650 | ch = 0; | |
1651 | ||
1652 | port->icount.rx++; | |
1653 | ||
1654 | lsr |= up->lsr_saved_flags; | |
1655 | up->lsr_saved_flags = 0; | |
1656 | ||
1657 | if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) { | |
1658 | if (lsr & UART_LSR_BI) { | |
1659 | lsr &= ~(UART_LSR_FE | UART_LSR_PE); | |
1660 | port->icount.brk++; | |
1661 | /* | |
1662 | * We do the SysRQ and SAK checking | |
1663 | * here because otherwise the break | |
1664 | * may get masked by ignore_status_mask | |
1665 | * or read_status_mask. | |
1666 | */ | |
1667 | if (uart_handle_break(port)) | |
1668 | return; | |
1669 | } else if (lsr & UART_LSR_PE) | |
1670 | port->icount.parity++; | |
1671 | else if (lsr & UART_LSR_FE) | |
1672 | port->icount.frame++; | |
1673 | if (lsr & UART_LSR_OE) | |
1674 | port->icount.overrun++; | |
1675 | ||
1676 | /* | |
1677 | * Mask off conditions which should be ignored. | |
1678 | */ | |
1679 | lsr &= port->read_status_mask; | |
1680 | ||
1681 | if (lsr & UART_LSR_BI) { | |
1682 | DEBUG_INTR("handling break...."); | |
1683 | flag = TTY_BREAK; | |
1684 | } else if (lsr & UART_LSR_PE) | |
1685 | flag = TTY_PARITY; | |
1686 | else if (lsr & UART_LSR_FE) | |
1687 | flag = TTY_FRAME; | |
1688 | } | |
1689 | if (uart_handle_sysrq_char(port, ch)) | |
1690 | return; | |
1691 | ||
1692 | uart_insert_char(port, lsr, UART_LSR_OE, ch, flag); | |
1693 | } | |
1694 | ||
b6830f6d PH |
1695 | /* |
1696 | * serial8250_rx_chars: processes according to the passed in LSR | |
1697 | * value, and returns the remaining LSR bits not handled | |
1698 | * by this Rx routine. | |
1699 | */ | |
d22f8f10 | 1700 | unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr) |
b6830f6d PH |
1701 | { |
1702 | struct uart_port *port = &up->port; | |
b6830f6d | 1703 | int max_count = 256; |
b6830f6d PH |
1704 | |
1705 | do { | |
3f6b3ce0 | 1706 | serial8250_read_char(up, lsr); |
d22f8f10 PH |
1707 | if (--max_count == 0) |
1708 | break; | |
b6830f6d | 1709 | lsr = serial_in(up, UART_LSR); |
d22f8f10 | 1710 | } while (lsr & (UART_LSR_DR | UART_LSR_BI)); |
6a597a38 | 1711 | |
b6830f6d | 1712 | tty_flip_buffer_push(&port->state->port); |
b6830f6d PH |
1713 | return lsr; |
1714 | } | |
1715 | EXPORT_SYMBOL_GPL(serial8250_rx_chars); | |
1716 | ||
1717 | void serial8250_tx_chars(struct uart_8250_port *up) | |
1718 | { | |
1719 | struct uart_port *port = &up->port; | |
1720 | struct circ_buf *xmit = &port->state->xmit; | |
1721 | int count; | |
1722 | ||
1723 | if (port->x_char) { | |
1724 | serial_out(up, UART_TX, port->x_char); | |
1725 | port->icount.tx++; | |
1726 | port->x_char = 0; | |
1727 | return; | |
1728 | } | |
1729 | if (uart_tx_stopped(port)) { | |
1730 | serial8250_stop_tx(port); | |
1731 | return; | |
1732 | } | |
1733 | if (uart_circ_empty(xmit)) { | |
1734 | __stop_tx(up); | |
1735 | return; | |
1736 | } | |
1737 | ||
1738 | count = up->tx_loadsz; | |
1739 | do { | |
1740 | serial_out(up, UART_TX, xmit->buf[xmit->tail]); | |
1741 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); | |
1742 | port->icount.tx++; | |
1743 | if (uart_circ_empty(xmit)) | |
1744 | break; | |
cee10c8c PH |
1745 | if ((up->capabilities & UART_CAP_HFIFO) && |
1746 | (serial_in(up, UART_LSR) & BOTH_EMPTY) != BOTH_EMPTY) | |
1747 | break; | |
b6830f6d PH |
1748 | } while (--count > 0); |
1749 | ||
1750 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
1751 | uart_write_wakeup(port); | |
1752 | ||
1753 | DEBUG_INTR("THRE..."); | |
1754 | ||
1755 | /* | |
1756 | * With RPM enabled, we have to wait until the FIFO is empty before the | |
1757 | * HW can go idle. So we get here once again with empty FIFO and disable | |
1758 | * the interrupt and RPM in __stop_tx() | |
1759 | */ | |
1760 | if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM)) | |
1761 | __stop_tx(up); | |
1762 | } | |
1763 | EXPORT_SYMBOL_GPL(serial8250_tx_chars); | |
1764 | ||
1765 | /* Caller holds uart port lock */ | |
1766 | unsigned int serial8250_modem_status(struct uart_8250_port *up) | |
1767 | { | |
1768 | struct uart_port *port = &up->port; | |
1769 | unsigned int status = serial_in(up, UART_MSR); | |
1770 | ||
1771 | status |= up->msr_saved_flags; | |
1772 | up->msr_saved_flags = 0; | |
1773 | if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI && | |
1774 | port->state != NULL) { | |
1775 | if (status & UART_MSR_TERI) | |
1776 | port->icount.rng++; | |
1777 | if (status & UART_MSR_DDSR) | |
1778 | port->icount.dsr++; | |
1779 | if (status & UART_MSR_DDCD) | |
1780 | uart_handle_dcd_change(port, status & UART_MSR_DCD); | |
1781 | if (status & UART_MSR_DCTS) | |
1782 | uart_handle_cts_change(port, status & UART_MSR_CTS); | |
1783 | ||
1784 | wake_up_interruptible(&port->state->port.delta_msr_wait); | |
1785 | } | |
1786 | ||
1787 | return status; | |
1788 | } | |
1789 | EXPORT_SYMBOL_GPL(serial8250_modem_status); | |
1790 | ||
1791 | /* | |
1792 | * This handles the interrupt from one port. | |
1793 | */ | |
1794 | int serial8250_handle_irq(struct uart_port *port, unsigned int iir) | |
1795 | { | |
1796 | unsigned char status; | |
1797 | unsigned long flags; | |
1798 | struct uart_8250_port *up = up_to_u8250p(port); | |
1799 | int dma_err = 0; | |
1800 | ||
1801 | if (iir & UART_IIR_NO_INT) | |
1802 | return 0; | |
1803 | ||
1804 | spin_lock_irqsave(&port->lock, flags); | |
1805 | ||
1806 | status = serial_port_in(port, UART_LSR); | |
1807 | ||
1808 | DEBUG_INTR("status = %x...", status); | |
1809 | ||
1810 | if (status & (UART_LSR_DR | UART_LSR_BI)) { | |
1811 | if (up->dma) | |
1812 | dma_err = up->dma->rx_dma(up, iir); | |
1813 | ||
1814 | if (!up->dma || dma_err) | |
1815 | status = serial8250_rx_chars(up, status); | |
1816 | } | |
1817 | serial8250_modem_status(up); | |
1818 | if ((!up->dma || (up->dma && up->dma->tx_err)) && | |
1819 | (status & UART_LSR_THRE)) | |
1820 | serial8250_tx_chars(up); | |
1821 | ||
1822 | spin_unlock_irqrestore(&port->lock, flags); | |
1823 | return 1; | |
1824 | } | |
1825 | EXPORT_SYMBOL_GPL(serial8250_handle_irq); | |
1826 | ||
1827 | static int serial8250_default_handle_irq(struct uart_port *port) | |
1828 | { | |
1829 | struct uart_8250_port *up = up_to_u8250p(port); | |
1830 | unsigned int iir; | |
1831 | int ret; | |
1832 | ||
1833 | serial8250_rpm_get(up); | |
1834 | ||
1835 | iir = serial_port_in(port, UART_IIR); | |
1836 | ret = serial8250_handle_irq(port, iir); | |
1837 | ||
1838 | serial8250_rpm_put(up); | |
1839 | return ret; | |
1840 | } | |
1841 | ||
1842 | /* | |
1843 | * These Exar UARTs have an extra interrupt indicator that could | |
1844 | * fire for a few unimplemented interrupts. One of which is a | |
1845 | * wakeup event when coming out of sleep. Put this here just | |
1846 | * to be on the safe side that these interrupts don't go unhandled. | |
1847 | */ | |
1848 | static int exar_handle_irq(struct uart_port *port) | |
1849 | { | |
1850 | unsigned char int0, int1, int2, int3; | |
1851 | unsigned int iir = serial_port_in(port, UART_IIR); | |
1852 | int ret; | |
1853 | ||
1854 | ret = serial8250_handle_irq(port, iir); | |
1855 | ||
1856 | if ((port->type == PORT_XR17V35X) || | |
1857 | (port->type == PORT_XR17D15X)) { | |
1858 | int0 = serial_port_in(port, 0x80); | |
1859 | int1 = serial_port_in(port, 0x81); | |
1860 | int2 = serial_port_in(port, 0x82); | |
1861 | int3 = serial_port_in(port, 0x83); | |
1862 | } | |
1863 | ||
1864 | return ret; | |
1865 | } | |
1866 | ||
1867 | static unsigned int serial8250_tx_empty(struct uart_port *port) | |
1868 | { | |
1869 | struct uart_8250_port *up = up_to_u8250p(port); | |
1870 | unsigned long flags; | |
1871 | unsigned int lsr; | |
1872 | ||
1873 | serial8250_rpm_get(up); | |
1874 | ||
1875 | spin_lock_irqsave(&port->lock, flags); | |
1876 | lsr = serial_port_in(port, UART_LSR); | |
1877 | up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS; | |
1878 | spin_unlock_irqrestore(&port->lock, flags); | |
1879 | ||
1880 | serial8250_rpm_put(up); | |
1881 | ||
1882 | return (lsr & BOTH_EMPTY) == BOTH_EMPTY ? TIOCSER_TEMT : 0; | |
1883 | } | |
1884 | ||
1885 | static unsigned int serial8250_get_mctrl(struct uart_port *port) | |
1886 | { | |
1887 | struct uart_8250_port *up = up_to_u8250p(port); | |
1888 | unsigned int status; | |
1889 | unsigned int ret; | |
1890 | ||
1891 | serial8250_rpm_get(up); | |
1892 | status = serial8250_modem_status(up); | |
1893 | serial8250_rpm_put(up); | |
1894 | ||
1895 | ret = 0; | |
1896 | if (status & UART_MSR_DCD) | |
1897 | ret |= TIOCM_CAR; | |
1898 | if (status & UART_MSR_RI) | |
1899 | ret |= TIOCM_RNG; | |
1900 | if (status & UART_MSR_DSR) | |
1901 | ret |= TIOCM_DSR; | |
1902 | if (status & UART_MSR_CTS) | |
1903 | ret |= TIOCM_CTS; | |
1904 | return ret; | |
1905 | } | |
1906 | ||
1907 | void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl) | |
1908 | { | |
1909 | struct uart_8250_port *up = up_to_u8250p(port); | |
1910 | unsigned char mcr = 0; | |
1911 | ||
1912 | if (mctrl & TIOCM_RTS) | |
1913 | mcr |= UART_MCR_RTS; | |
1914 | if (mctrl & TIOCM_DTR) | |
1915 | mcr |= UART_MCR_DTR; | |
1916 | if (mctrl & TIOCM_OUT1) | |
1917 | mcr |= UART_MCR_OUT1; | |
1918 | if (mctrl & TIOCM_OUT2) | |
1919 | mcr |= UART_MCR_OUT2; | |
1920 | if (mctrl & TIOCM_LOOP) | |
1921 | mcr |= UART_MCR_LOOP; | |
1922 | ||
1923 | mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr; | |
1924 | ||
1925 | serial_port_out(port, UART_MCR, mcr); | |
1926 | } | |
1927 | EXPORT_SYMBOL_GPL(serial8250_do_set_mctrl); | |
1928 | ||
1929 | static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl) | |
1930 | { | |
1931 | if (port->set_mctrl) | |
1932 | port->set_mctrl(port, mctrl); | |
1933 | else | |
1934 | serial8250_do_set_mctrl(port, mctrl); | |
1935 | } | |
1936 | ||
1937 | static void serial8250_break_ctl(struct uart_port *port, int break_state) | |
1938 | { | |
1939 | struct uart_8250_port *up = up_to_u8250p(port); | |
1940 | unsigned long flags; | |
1941 | ||
1942 | serial8250_rpm_get(up); | |
1943 | spin_lock_irqsave(&port->lock, flags); | |
1944 | if (break_state == -1) | |
1945 | up->lcr |= UART_LCR_SBC; | |
1946 | else | |
1947 | up->lcr &= ~UART_LCR_SBC; | |
1948 | serial_port_out(port, UART_LCR, up->lcr); | |
1949 | spin_unlock_irqrestore(&port->lock, flags); | |
1950 | serial8250_rpm_put(up); | |
1951 | } | |
1952 | ||
1953 | /* | |
1954 | * Wait for transmitter & holding register to empty | |
1955 | */ | |
1956 | static void wait_for_xmitr(struct uart_8250_port *up, int bits) | |
1957 | { | |
1958 | unsigned int status, tmout = 10000; | |
1959 | ||
1960 | /* Wait up to 10ms for the character(s) to be sent. */ | |
1961 | for (;;) { | |
1962 | status = serial_in(up, UART_LSR); | |
1963 | ||
1964 | up->lsr_saved_flags |= status & LSR_SAVE_FLAGS; | |
1965 | ||
1966 | if ((status & bits) == bits) | |
1967 | break; | |
1968 | if (--tmout == 0) | |
1969 | break; | |
1970 | udelay(1); | |
1971 | } | |
1972 | ||
1973 | /* Wait up to 1s for flow control if necessary */ | |
1974 | if (up->port.flags & UPF_CONS_FLOW) { | |
1975 | unsigned int tmout; | |
1a33e342 | 1976 | |
b6830f6d PH |
1977 | for (tmout = 1000000; tmout; tmout--) { |
1978 | unsigned int msr = serial_in(up, UART_MSR); | |
1979 | up->msr_saved_flags |= msr & MSR_SAVE_FLAGS; | |
1980 | if (msr & UART_MSR_CTS) | |
1981 | break; | |
1982 | udelay(1); | |
1983 | touch_nmi_watchdog(); | |
1984 | } | |
1985 | } | |
1986 | } | |
1987 | ||
1988 | #ifdef CONFIG_CONSOLE_POLL | |
1989 | /* | |
1990 | * Console polling routines for writing and reading from the uart while | |
1991 | * in an interrupt or debug context. | |
1992 | */ | |
1993 | ||
1994 | static int serial8250_get_poll_char(struct uart_port *port) | |
1995 | { | |
1996 | struct uart_8250_port *up = up_to_u8250p(port); | |
1997 | unsigned char lsr; | |
1998 | int status; | |
1999 | ||
2000 | serial8250_rpm_get(up); | |
2001 | ||
2002 | lsr = serial_port_in(port, UART_LSR); | |
2003 | ||
2004 | if (!(lsr & UART_LSR_DR)) { | |
2005 | status = NO_POLL_CHAR; | |
2006 | goto out; | |
2007 | } | |
2008 | ||
2009 | status = serial_port_in(port, UART_RX); | |
2010 | out: | |
2011 | serial8250_rpm_put(up); | |
2012 | return status; | |
2013 | } | |
2014 | ||
2015 | ||
2016 | static void serial8250_put_poll_char(struct uart_port *port, | |
2017 | unsigned char c) | |
2018 | { | |
2019 | unsigned int ier; | |
2020 | struct uart_8250_port *up = up_to_u8250p(port); | |
2021 | ||
2022 | serial8250_rpm_get(up); | |
2023 | /* | |
2024 | * First save the IER then disable the interrupts | |
2025 | */ | |
2026 | ier = serial_port_in(port, UART_IER); | |
2027 | if (up->capabilities & UART_CAP_UUE) | |
2028 | serial_port_out(port, UART_IER, UART_IER_UUE); | |
2029 | else | |
2030 | serial_port_out(port, UART_IER, 0); | |
2031 | ||
2032 | wait_for_xmitr(up, BOTH_EMPTY); | |
2033 | /* | |
2034 | * Send the character out. | |
2035 | */ | |
2036 | serial_port_out(port, UART_TX, c); | |
2037 | ||
2038 | /* | |
2039 | * Finally, wait for transmitter to become empty | |
2040 | * and restore the IER | |
2041 | */ | |
2042 | wait_for_xmitr(up, BOTH_EMPTY); | |
2043 | serial_port_out(port, UART_IER, ier); | |
2044 | serial8250_rpm_put(up); | |
2045 | } | |
2046 | ||
2047 | #endif /* CONFIG_CONSOLE_POLL */ | |
2048 | ||
2049 | int serial8250_do_startup(struct uart_port *port) | |
2050 | { | |
2051 | struct uart_8250_port *up = up_to_u8250p(port); | |
2052 | unsigned long flags; | |
2053 | unsigned char lsr, iir; | |
2054 | int retval; | |
2055 | ||
b6830f6d PH |
2056 | if (!port->fifosize) |
2057 | port->fifosize = uart_config[port->type].fifo_size; | |
2058 | if (!up->tx_loadsz) | |
2059 | up->tx_loadsz = uart_config[port->type].tx_loadsz; | |
2060 | if (!up->capabilities) | |
2061 | up->capabilities = uart_config[port->type].flags; | |
2062 | up->mcr = 0; | |
2063 | ||
2064 | if (port->iotype != up->cur_iotype) | |
2065 | set_io_from_upio(port); | |
2066 | ||
2067 | serial8250_rpm_get(up); | |
2068 | if (port->type == PORT_16C950) { | |
2069 | /* Wake up and initialize UART */ | |
2070 | up->acr = 0; | |
2071 | serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B); | |
2072 | serial_port_out(port, UART_EFR, UART_EFR_ECB); | |
2073 | serial_port_out(port, UART_IER, 0); | |
2074 | serial_port_out(port, UART_LCR, 0); | |
2075 | serial_icr_write(up, UART_CSR, 0); /* Reset the UART */ | |
2076 | serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B); | |
2077 | serial_port_out(port, UART_EFR, UART_EFR_ECB); | |
2078 | serial_port_out(port, UART_LCR, 0); | |
2079 | } | |
2080 | ||
2081 | #ifdef CONFIG_SERIAL_8250_RSA | |
2082 | /* | |
2083 | * If this is an RSA port, see if we can kick it up to the | |
2084 | * higher speed clock. | |
2085 | */ | |
2086 | enable_rsa(up); | |
2087 | #endif | |
da891641 JR |
2088 | |
2089 | if (port->type == PORT_XR17V35X) { | |
2090 | /* | |
2091 | * First enable access to IER [7:5], ISR [5:4], FCR [5:4], | |
2092 | * MCR [7:5] and MSR [7:0] | |
2093 | */ | |
2094 | serial_port_out(port, UART_XR_EFR, UART_EFR_ECB); | |
2095 | ||
2096 | /* | |
2097 | * Make sure all interrups are masked until initialization is | |
2098 | * complete and the FIFOs are cleared | |
2099 | */ | |
2100 | serial_port_out(port, UART_IER, 0); | |
2101 | } | |
2102 | ||
b6830f6d PH |
2103 | /* |
2104 | * Clear the FIFO buffers and disable them. | |
2105 | * (they will be reenabled in set_termios()) | |
2106 | */ | |
2107 | serial8250_clear_fifos(up); | |
2108 | ||
2109 | /* | |
2110 | * Clear the interrupt registers. | |
2111 | */ | |
2112 | serial_port_in(port, UART_LSR); | |
2113 | serial_port_in(port, UART_RX); | |
2114 | serial_port_in(port, UART_IIR); | |
2115 | serial_port_in(port, UART_MSR); | |
2116 | ||
2117 | /* | |
2118 | * At this point, there's no way the LSR could still be 0xff; | |
2119 | * if it is, then bail out, because there's likely no UART | |
2120 | * here. | |
2121 | */ | |
2122 | if (!(port->flags & UPF_BUGGY_UART) && | |
2123 | (serial_port_in(port, UART_LSR) == 0xff)) { | |
2124 | printk_ratelimited(KERN_INFO "ttyS%d: LSR safety check engaged!\n", | |
2125 | serial_index(port)); | |
2126 | retval = -ENODEV; | |
2127 | goto out; | |
2128 | } | |
2129 | ||
2130 | /* | |
2131 | * For a XR16C850, we need to set the trigger levels | |
2132 | */ | |
2133 | if (port->type == PORT_16850) { | |
2134 | unsigned char fctr; | |
2135 | ||
2136 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); | |
2137 | ||
2138 | fctr = serial_in(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX); | |
2139 | serial_port_out(port, UART_FCTR, | |
2140 | fctr | UART_FCTR_TRGD | UART_FCTR_RX); | |
2141 | serial_port_out(port, UART_TRG, UART_TRG_96); | |
2142 | serial_port_out(port, UART_FCTR, | |
2143 | fctr | UART_FCTR_TRGD | UART_FCTR_TX); | |
2144 | serial_port_out(port, UART_TRG, UART_TRG_96); | |
2145 | ||
2146 | serial_port_out(port, UART_LCR, 0); | |
2147 | } | |
2148 | ||
2149 | if (port->irq) { | |
2150 | unsigned char iir1; | |
2151 | /* | |
2152 | * Test for UARTs that do not reassert THRE when the | |
2153 | * transmitter is idle and the interrupt has already | |
2154 | * been cleared. Real 16550s should always reassert | |
2155 | * this interrupt whenever the transmitter is idle and | |
2156 | * the interrupt is enabled. Delays are necessary to | |
2157 | * allow register changes to become visible. | |
2158 | */ | |
2159 | spin_lock_irqsave(&port->lock, flags); | |
2160 | if (up->port.irqflags & IRQF_SHARED) | |
2161 | disable_irq_nosync(port->irq); | |
2162 | ||
2163 | wait_for_xmitr(up, UART_LSR_THRE); | |
2164 | serial_port_out_sync(port, UART_IER, UART_IER_THRI); | |
2165 | udelay(1); /* allow THRE to set */ | |
2166 | iir1 = serial_port_in(port, UART_IIR); | |
2167 | serial_port_out(port, UART_IER, 0); | |
2168 | serial_port_out_sync(port, UART_IER, UART_IER_THRI); | |
2169 | udelay(1); /* allow a working UART time to re-assert THRE */ | |
2170 | iir = serial_port_in(port, UART_IIR); | |
2171 | serial_port_out(port, UART_IER, 0); | |
2172 | ||
2173 | if (port->irqflags & IRQF_SHARED) | |
2174 | enable_irq(port->irq); | |
2175 | spin_unlock_irqrestore(&port->lock, flags); | |
2176 | ||
2177 | /* | |
2178 | * If the interrupt is not reasserted, or we otherwise | |
2179 | * don't trust the iir, setup a timer to kick the UART | |
2180 | * on a regular basis. | |
2181 | */ | |
2182 | if ((!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) || | |
2183 | up->port.flags & UPF_BUG_THRE) { | |
2184 | up->bugs |= UART_BUG_THRE; | |
2185 | } | |
2186 | } | |
2187 | ||
2188 | retval = up->ops->setup_irq(up); | |
2189 | if (retval) | |
2190 | goto out; | |
2191 | ||
2192 | /* | |
2193 | * Now, initialize the UART | |
2194 | */ | |
2195 | serial_port_out(port, UART_LCR, UART_LCR_WLEN8); | |
2196 | ||
2197 | spin_lock_irqsave(&port->lock, flags); | |
2198 | if (up->port.flags & UPF_FOURPORT) { | |
2199 | if (!up->port.irq) | |
2200 | up->port.mctrl |= TIOCM_OUT1; | |
2201 | } else | |
2202 | /* | |
2203 | * Most PC uarts need OUT2 raised to enable interrupts. | |
2204 | */ | |
2205 | if (port->irq) | |
2206 | up->port.mctrl |= TIOCM_OUT2; | |
2207 | ||
2208 | serial8250_set_mctrl(port, port->mctrl); | |
2209 | ||
740dc2de AW |
2210 | /* |
2211 | * Serial over Lan (SoL) hack: | |
2212 | * Intel 8257x Gigabit ethernet chips have a 16550 emulation, to be | |
2213 | * used for Serial Over Lan. Those chips take a longer time than a | |
2214 | * normal serial device to signalize that a transmission data was | |
2215 | * queued. Due to that, the above test generally fails. One solution | |
2216 | * would be to delay the reading of iir. However, this is not | |
2217 | * reliable, since the timeout is variable. So, let's just don't | |
2218 | * test if we receive TX irq. This way, we'll never enable | |
2219 | * UART_BUG_TXEN. | |
b6830f6d PH |
2220 | */ |
2221 | if (up->port.flags & UPF_NO_TXEN_TEST) | |
2222 | goto dont_test_tx_en; | |
2223 | ||
2224 | /* | |
740dc2de AW |
2225 | * Do a quick test to see if we receive an interrupt when we enable |
2226 | * the TX irq. | |
b6830f6d PH |
2227 | */ |
2228 | serial_port_out(port, UART_IER, UART_IER_THRI); | |
2229 | lsr = serial_port_in(port, UART_LSR); | |
2230 | iir = serial_port_in(port, UART_IIR); | |
2231 | serial_port_out(port, UART_IER, 0); | |
2232 | ||
2233 | if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) { | |
2234 | if (!(up->bugs & UART_BUG_TXEN)) { | |
2235 | up->bugs |= UART_BUG_TXEN; | |
2236 | pr_debug("ttyS%d - enabling bad tx status workarounds\n", | |
2237 | serial_index(port)); | |
2238 | } | |
2239 | } else { | |
2240 | up->bugs &= ~UART_BUG_TXEN; | |
2241 | } | |
2242 | ||
2243 | dont_test_tx_en: | |
2244 | spin_unlock_irqrestore(&port->lock, flags); | |
2245 | ||
2246 | /* | |
2247 | * Clear the interrupt registers again for luck, and clear the | |
2248 | * saved flags to avoid getting false values from polling | |
2249 | * routines or the previous session. | |
2250 | */ | |
2251 | serial_port_in(port, UART_LSR); | |
2252 | serial_port_in(port, UART_RX); | |
2253 | serial_port_in(port, UART_IIR); | |
2254 | serial_port_in(port, UART_MSR); | |
2255 | up->lsr_saved_flags = 0; | |
2256 | up->msr_saved_flags = 0; | |
2257 | ||
2258 | /* | |
2259 | * Request DMA channels for both RX and TX. | |
2260 | */ | |
2261 | if (up->dma) { | |
2262 | retval = serial8250_request_dma(up); | |
2263 | if (retval) { | |
2264 | pr_warn_ratelimited("ttyS%d - failed to request DMA\n", | |
2265 | serial_index(port)); | |
2266 | up->dma = NULL; | |
2267 | } | |
2268 | } | |
2269 | ||
2270 | /* | |
ee3ad90b PH |
2271 | * Set the IER shadow for rx interrupts but defer actual interrupt |
2272 | * enable until after the FIFOs are enabled; otherwise, an already- | |
2273 | * active sender can swamp the interrupt handler with "too much work". | |
b6830f6d PH |
2274 | */ |
2275 | up->ier = UART_IER_RLSI | UART_IER_RDI; | |
b6830f6d PH |
2276 | |
2277 | if (port->flags & UPF_FOURPORT) { | |
2278 | unsigned int icp; | |
2279 | /* | |
2280 | * Enable interrupts on the AST Fourport board | |
2281 | */ | |
2282 | icp = (port->iobase & 0xfe0) | 0x01f; | |
2283 | outb_p(0x80, icp); | |
2284 | inb_p(icp); | |
2285 | } | |
2286 | retval = 0; | |
2287 | out: | |
2288 | serial8250_rpm_put(up); | |
2289 | return retval; | |
2290 | } | |
2291 | EXPORT_SYMBOL_GPL(serial8250_do_startup); | |
2292 | ||
2293 | static int serial8250_startup(struct uart_port *port) | |
2294 | { | |
2295 | if (port->startup) | |
2296 | return port->startup(port); | |
2297 | return serial8250_do_startup(port); | |
2298 | } | |
2299 | ||
2300 | void serial8250_do_shutdown(struct uart_port *port) | |
2301 | { | |
2302 | struct uart_8250_port *up = up_to_u8250p(port); | |
2303 | unsigned long flags; | |
2304 | ||
2305 | serial8250_rpm_get(up); | |
2306 | /* | |
2307 | * Disable interrupts from this port | |
2308 | */ | |
611e0d83 | 2309 | spin_lock_irqsave(&port->lock, flags); |
b6830f6d PH |
2310 | up->ier = 0; |
2311 | serial_port_out(port, UART_IER, 0); | |
611e0d83 PH |
2312 | spin_unlock_irqrestore(&port->lock, flags); |
2313 | ||
2314 | synchronize_irq(port->irq); | |
b6830f6d PH |
2315 | |
2316 | if (up->dma) | |
2317 | serial8250_release_dma(up); | |
2318 | ||
2319 | spin_lock_irqsave(&port->lock, flags); | |
2320 | if (port->flags & UPF_FOURPORT) { | |
2321 | /* reset interrupts on the AST Fourport board */ | |
2322 | inb((port->iobase & 0xfe0) | 0x1f); | |
2323 | port->mctrl |= TIOCM_OUT1; | |
2324 | } else | |
2325 | port->mctrl &= ~TIOCM_OUT2; | |
2326 | ||
2327 | serial8250_set_mctrl(port, port->mctrl); | |
2328 | spin_unlock_irqrestore(&port->lock, flags); | |
2329 | ||
2330 | /* | |
2331 | * Disable break condition and FIFOs | |
2332 | */ | |
2333 | serial_port_out(port, UART_LCR, | |
2334 | serial_port_in(port, UART_LCR) & ~UART_LCR_SBC); | |
2335 | serial8250_clear_fifos(up); | |
2336 | ||
2337 | #ifdef CONFIG_SERIAL_8250_RSA | |
2338 | /* | |
2339 | * Reset the RSA board back to 115kbps compat mode. | |
2340 | */ | |
2341 | disable_rsa(up); | |
2342 | #endif | |
2343 | ||
2344 | /* | |
2345 | * Read data port to reset things, and then unlink from | |
2346 | * the IRQ chain. | |
2347 | */ | |
2348 | serial_port_in(port, UART_RX); | |
2349 | serial8250_rpm_put(up); | |
2350 | ||
2351 | up->ops->release_irq(up); | |
2352 | } | |
2353 | EXPORT_SYMBOL_GPL(serial8250_do_shutdown); | |
2354 | ||
2355 | static void serial8250_shutdown(struct uart_port *port) | |
2356 | { | |
2357 | if (port->shutdown) | |
2358 | port->shutdown(port); | |
2359 | else | |
2360 | serial8250_do_shutdown(port); | |
2361 | } | |
2362 | ||
2363 | /* | |
2364 | * XR17V35x UARTs have an extra fractional divisor register (DLD) | |
2365 | * Calculate divisor with extra 4-bit fractional portion | |
2366 | */ | |
2367 | static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up, | |
2368 | unsigned int baud, | |
2369 | unsigned int *frac) | |
2370 | { | |
2371 | struct uart_port *port = &up->port; | |
2372 | unsigned int quot_16; | |
2373 | ||
2374 | quot_16 = DIV_ROUND_CLOSEST(port->uartclk, baud); | |
2375 | *frac = quot_16 & 0x0f; | |
2376 | ||
2377 | return quot_16 >> 4; | |
2378 | } | |
2379 | ||
2380 | static unsigned int serial8250_get_divisor(struct uart_8250_port *up, | |
2381 | unsigned int baud, | |
2382 | unsigned int *frac) | |
2383 | { | |
2384 | struct uart_port *port = &up->port; | |
2385 | unsigned int quot; | |
2386 | ||
2387 | /* | |
2388 | * Handle magic divisors for baud rates above baud_base on | |
2389 | * SMSC SuperIO chips. | |
2390 | * | |
2391 | */ | |
2392 | if ((port->flags & UPF_MAGIC_MULTIPLIER) && | |
2393 | baud == (port->uartclk/4)) | |
2394 | quot = 0x8001; | |
2395 | else if ((port->flags & UPF_MAGIC_MULTIPLIER) && | |
2396 | baud == (port->uartclk/8)) | |
2397 | quot = 0x8002; | |
2398 | else if (up->port.type == PORT_XR17V35X) | |
2399 | quot = xr17v35x_get_divisor(up, baud, frac); | |
2400 | else | |
2401 | quot = uart_get_divisor(port, baud); | |
2402 | ||
2403 | /* | |
2404 | * Oxford Semi 952 rev B workaround | |
2405 | */ | |
2406 | if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0) | |
2407 | quot++; | |
2408 | ||
2409 | return quot; | |
2410 | } | |
2411 | ||
2412 | static unsigned char serial8250_compute_lcr(struct uart_8250_port *up, | |
2413 | tcflag_t c_cflag) | |
2414 | { | |
2415 | unsigned char cval; | |
2416 | ||
2417 | switch (c_cflag & CSIZE) { | |
2418 | case CS5: | |
2419 | cval = UART_LCR_WLEN5; | |
2420 | break; | |
2421 | case CS6: | |
2422 | cval = UART_LCR_WLEN6; | |
2423 | break; | |
2424 | case CS7: | |
2425 | cval = UART_LCR_WLEN7; | |
2426 | break; | |
2427 | default: | |
2428 | case CS8: | |
2429 | cval = UART_LCR_WLEN8; | |
2430 | break; | |
2431 | } | |
2432 | ||
2433 | if (c_cflag & CSTOPB) | |
2434 | cval |= UART_LCR_STOP; | |
2435 | if (c_cflag & PARENB) { | |
2436 | cval |= UART_LCR_PARITY; | |
2437 | if (up->bugs & UART_BUG_PARITY) | |
2438 | up->fifo_bug = true; | |
2439 | } | |
2440 | if (!(c_cflag & PARODD)) | |
2441 | cval |= UART_LCR_EPAR; | |
2442 | #ifdef CMSPAR | |
2443 | if (c_cflag & CMSPAR) | |
2444 | cval |= UART_LCR_SPAR; | |
2445 | #endif | |
2446 | ||
2447 | return cval; | |
2448 | } | |
2449 | ||
2450 | static void serial8250_set_divisor(struct uart_port *port, unsigned int baud, | |
2451 | unsigned int quot, unsigned int quot_frac) | |
2452 | { | |
2453 | struct uart_8250_port *up = up_to_u8250p(port); | |
2454 | ||
2455 | /* Workaround to enable 115200 baud on OMAP1510 internal ports */ | |
2456 | if (is_omap1510_8250(up)) { | |
2457 | if (baud == 115200) { | |
2458 | quot = 1; | |
2459 | serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1); | |
2460 | } else | |
2461 | serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0); | |
2462 | } | |
2463 | ||
2464 | /* | |
2465 | * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2, | |
2466 | * otherwise just set DLAB | |
2467 | */ | |
2468 | if (up->capabilities & UART_NATSEMI) | |
2469 | serial_port_out(port, UART_LCR, 0xe0); | |
2470 | else | |
2471 | serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB); | |
2472 | ||
2473 | serial_dl_write(up, quot); | |
2474 | ||
2475 | /* XR17V35x UARTs have an extra fractional divisor register (DLD) */ | |
2476 | if (up->port.type == PORT_XR17V35X) | |
2477 | serial_port_out(port, 0x2, quot_frac); | |
2478 | } | |
2479 | ||
b3d67936 AW |
2480 | static unsigned int serial8250_get_baud_rate(struct uart_port *port, |
2481 | struct ktermios *termios, | |
2482 | struct ktermios *old) | |
4f56f3fd JH |
2483 | { |
2484 | unsigned int tolerance = port->uartclk / 100; | |
2485 | ||
2486 | /* | |
2487 | * Ask the core to calculate the divisor for us. | |
2488 | * Allow 1% tolerance at the upper limit so uart clks marginally | |
2489 | * slower than nominal still match standard baud rates without | |
2490 | * causing transmission errors. | |
2491 | */ | |
2492 | return uart_get_baud_rate(port, termios, old, | |
2493 | port->uartclk / 16 / 0xffff, | |
2494 | (port->uartclk + tolerance) / 16); | |
2495 | } | |
2496 | ||
b6830f6d PH |
2497 | void |
2498 | serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, | |
6d7c157f | 2499 | struct ktermios *old) |
b6830f6d PH |
2500 | { |
2501 | struct uart_8250_port *up = up_to_u8250p(port); | |
2502 | unsigned char cval; | |
2503 | unsigned long flags; | |
2504 | unsigned int baud, quot, frac = 0; | |
2505 | ||
2506 | cval = serial8250_compute_lcr(up, termios->c_cflag); | |
2507 | ||
4f56f3fd | 2508 | baud = serial8250_get_baud_rate(port, termios, old); |
b6830f6d PH |
2509 | quot = serial8250_get_divisor(up, baud, &frac); |
2510 | ||
2511 | /* | |
2512 | * Ok, we're now changing the port state. Do it with | |
2513 | * interrupts disabled. | |
2514 | */ | |
2515 | serial8250_rpm_get(up); | |
2516 | spin_lock_irqsave(&port->lock, flags); | |
2517 | ||
2518 | up->lcr = cval; /* Save computed LCR */ | |
2519 | ||
2520 | if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) { | |
2521 | /* NOTE: If fifo_bug is not set, a user can set RX_trigger. */ | |
2522 | if ((baud < 2400 && !up->dma) || up->fifo_bug) { | |
2523 | up->fcr &= ~UART_FCR_TRIGGER_MASK; | |
2524 | up->fcr |= UART_FCR_TRIGGER_1; | |
2525 | } | |
2526 | } | |
2527 | ||
2528 | /* | |
2529 | * MCR-based auto flow control. When AFE is enabled, RTS will be | |
2530 | * deasserted when the receive FIFO contains more characters than | |
2531 | * the trigger, or the MCR RTS bit is cleared. In the case where | |
2532 | * the remote UART is not using CTS auto flow control, we must | |
2533 | * have sufficient FIFO entries for the latency of the remote | |
2534 | * UART to respond. IOW, at least 32 bytes of FIFO. | |
2535 | */ | |
2536 | if (up->capabilities & UART_CAP_AFE && port->fifosize >= 32) { | |
2537 | up->mcr &= ~UART_MCR_AFE; | |
2538 | if (termios->c_cflag & CRTSCTS) | |
2539 | up->mcr |= UART_MCR_AFE; | |
2540 | } | |
2541 | ||
2542 | /* | |
2543 | * Update the per-port timeout. | |
2544 | */ | |
2545 | uart_update_timeout(port, termios->c_cflag, baud); | |
2546 | ||
2547 | port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; | |
2548 | if (termios->c_iflag & INPCK) | |
2549 | port->read_status_mask |= UART_LSR_FE | UART_LSR_PE; | |
2550 | if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) | |
2551 | port->read_status_mask |= UART_LSR_BI; | |
2552 | ||
2553 | /* | |
2554 | * Characteres to ignore | |
2555 | */ | |
2556 | port->ignore_status_mask = 0; | |
2557 | if (termios->c_iflag & IGNPAR) | |
2558 | port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; | |
2559 | if (termios->c_iflag & IGNBRK) { | |
2560 | port->ignore_status_mask |= UART_LSR_BI; | |
2561 | /* | |
2562 | * If we're ignoring parity and break indicators, | |
2563 | * ignore overruns too (for real raw support). | |
2564 | */ | |
2565 | if (termios->c_iflag & IGNPAR) | |
2566 | port->ignore_status_mask |= UART_LSR_OE; | |
2567 | } | |
2568 | ||
2569 | /* | |
2570 | * ignore all characters if CREAD is not set | |
2571 | */ | |
2572 | if ((termios->c_cflag & CREAD) == 0) | |
2573 | port->ignore_status_mask |= UART_LSR_DR; | |
2574 | ||
2575 | /* | |
2576 | * CTS flow control flag and modem status interrupts | |
2577 | */ | |
2578 | up->ier &= ~UART_IER_MSI; | |
2579 | if (!(up->bugs & UART_BUG_NOMSR) && | |
2580 | UART_ENABLE_MS(&up->port, termios->c_cflag)) | |
2581 | up->ier |= UART_IER_MSI; | |
2582 | if (up->capabilities & UART_CAP_UUE) | |
2583 | up->ier |= UART_IER_UUE; | |
2584 | if (up->capabilities & UART_CAP_RTOIE) | |
2585 | up->ier |= UART_IER_RTOIE; | |
2586 | ||
2587 | serial_port_out(port, UART_IER, up->ier); | |
2588 | ||
2589 | if (up->capabilities & UART_CAP_EFR) { | |
2590 | unsigned char efr = 0; | |
2591 | /* | |
2592 | * TI16C752/Startech hardware flow control. FIXME: | |
2593 | * - TI16C752 requires control thresholds to be set. | |
2594 | * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled. | |
2595 | */ | |
2596 | if (termios->c_cflag & CRTSCTS) | |
2597 | efr |= UART_EFR_CTS; | |
2598 | ||
2599 | serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B); | |
2600 | if (port->flags & UPF_EXAR_EFR) | |
2601 | serial_port_out(port, UART_XR_EFR, efr); | |
2602 | else | |
2603 | serial_port_out(port, UART_EFR, efr); | |
2604 | } | |
2605 | ||
2606 | serial8250_set_divisor(port, baud, quot, frac); | |
2607 | ||
2608 | /* | |
2609 | * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR | |
2610 | * is written without DLAB set, this mode will be disabled. | |
2611 | */ | |
2612 | if (port->type == PORT_16750) | |
2613 | serial_port_out(port, UART_FCR, up->fcr); | |
2614 | ||
2615 | serial_port_out(port, UART_LCR, up->lcr); /* reset DLAB */ | |
2616 | if (port->type != PORT_16750) { | |
2617 | /* emulated UARTs (Lucent Venus 167x) need two steps */ | |
2618 | if (up->fcr & UART_FCR_ENABLE_FIFO) | |
2619 | serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO); | |
2620 | serial_port_out(port, UART_FCR, up->fcr); /* set fcr */ | |
2621 | } | |
2622 | serial8250_set_mctrl(port, port->mctrl); | |
2623 | spin_unlock_irqrestore(&port->lock, flags); | |
2624 | serial8250_rpm_put(up); | |
2625 | ||
2626 | /* Don't rewrite B0 */ | |
2627 | if (tty_termios_baud_rate(termios)) | |
2628 | tty_termios_encode_baud_rate(termios, baud, baud); | |
2629 | } | |
2630 | EXPORT_SYMBOL(serial8250_do_set_termios); | |
2631 | ||
2632 | static void | |
2633 | serial8250_set_termios(struct uart_port *port, struct ktermios *termios, | |
2634 | struct ktermios *old) | |
2635 | { | |
2636 | if (port->set_termios) | |
2637 | port->set_termios(port, termios, old); | |
2638 | else | |
2639 | serial8250_do_set_termios(port, termios, old); | |
2640 | } | |
2641 | ||
2642 | static void | |
2643 | serial8250_set_ldisc(struct uart_port *port, struct ktermios *termios) | |
2644 | { | |
2645 | if (termios->c_line == N_PPS) { | |
2646 | port->flags |= UPF_HARDPPS_CD; | |
2647 | spin_lock_irq(&port->lock); | |
2648 | serial8250_enable_ms(port); | |
2649 | spin_unlock_irq(&port->lock); | |
2650 | } else { | |
2651 | port->flags &= ~UPF_HARDPPS_CD; | |
2652 | if (!UART_ENABLE_MS(port, termios->c_cflag)) { | |
2653 | spin_lock_irq(&port->lock); | |
2654 | serial8250_disable_ms(port); | |
2655 | spin_unlock_irq(&port->lock); | |
2656 | } | |
2657 | } | |
2658 | } | |
2659 | ||
2660 | ||
2661 | void serial8250_do_pm(struct uart_port *port, unsigned int state, | |
2662 | unsigned int oldstate) | |
2663 | { | |
2664 | struct uart_8250_port *p = up_to_u8250p(port); | |
2665 | ||
2666 | serial8250_set_sleep(p, state != 0); | |
2667 | } | |
2668 | EXPORT_SYMBOL(serial8250_do_pm); | |
2669 | ||
2670 | static void | |
2671 | serial8250_pm(struct uart_port *port, unsigned int state, | |
2672 | unsigned int oldstate) | |
2673 | { | |
2674 | if (port->pm) | |
2675 | port->pm(port, state, oldstate); | |
2676 | else | |
2677 | serial8250_do_pm(port, state, oldstate); | |
2678 | } | |
2679 | ||
2680 | static unsigned int serial8250_port_size(struct uart_8250_port *pt) | |
2681 | { | |
2682 | if (pt->port.mapsize) | |
2683 | return pt->port.mapsize; | |
2684 | if (pt->port.iotype == UPIO_AU) { | |
2685 | if (pt->port.type == PORT_RT2880) | |
2686 | return 0x100; | |
2687 | return 0x1000; | |
2688 | } | |
2689 | if (is_omap1_8250(pt)) | |
2690 | return 0x16 << pt->port.regshift; | |
2691 | ||
2692 | return 8 << pt->port.regshift; | |
2693 | } | |
2694 | ||
2695 | /* | |
2696 | * Resource handling. | |
2697 | */ | |
2698 | static int serial8250_request_std_resource(struct uart_8250_port *up) | |
2699 | { | |
2700 | unsigned int size = serial8250_port_size(up); | |
2701 | struct uart_port *port = &up->port; | |
2702 | int ret = 0; | |
2703 | ||
2704 | switch (port->iotype) { | |
2705 | case UPIO_AU: | |
2706 | case UPIO_TSI: | |
2707 | case UPIO_MEM32: | |
2708 | case UPIO_MEM32BE: | |
bd94c407 | 2709 | case UPIO_MEM16: |
b6830f6d PH |
2710 | case UPIO_MEM: |
2711 | if (!port->mapbase) | |
2712 | break; | |
2713 | ||
2714 | if (!request_mem_region(port->mapbase, size, "serial")) { | |
2715 | ret = -EBUSY; | |
2716 | break; | |
2717 | } | |
2718 | ||
2719 | if (port->flags & UPF_IOREMAP) { | |
2720 | port->membase = ioremap_nocache(port->mapbase, size); | |
2721 | if (!port->membase) { | |
2722 | release_mem_region(port->mapbase, size); | |
2723 | ret = -ENOMEM; | |
2724 | } | |
2725 | } | |
2726 | break; | |
2727 | ||
2728 | case UPIO_HUB6: | |
2729 | case UPIO_PORT: | |
2730 | if (!request_region(port->iobase, size, "serial")) | |
2731 | ret = -EBUSY; | |
2732 | break; | |
2733 | } | |
2734 | return ret; | |
2735 | } | |
2736 | ||
2737 | static void serial8250_release_std_resource(struct uart_8250_port *up) | |
2738 | { | |
2739 | unsigned int size = serial8250_port_size(up); | |
2740 | struct uart_port *port = &up->port; | |
2741 | ||
2742 | switch (port->iotype) { | |
2743 | case UPIO_AU: | |
2744 | case UPIO_TSI: | |
2745 | case UPIO_MEM32: | |
2746 | case UPIO_MEM32BE: | |
bd94c407 | 2747 | case UPIO_MEM16: |
b6830f6d PH |
2748 | case UPIO_MEM: |
2749 | if (!port->mapbase) | |
2750 | break; | |
2751 | ||
2752 | if (port->flags & UPF_IOREMAP) { | |
2753 | iounmap(port->membase); | |
2754 | port->membase = NULL; | |
2755 | } | |
2756 | ||
2757 | release_mem_region(port->mapbase, size); | |
2758 | break; | |
2759 | ||
2760 | case UPIO_HUB6: | |
2761 | case UPIO_PORT: | |
2762 | release_region(port->iobase, size); | |
2763 | break; | |
2764 | } | |
2765 | } | |
2766 | ||
2767 | static void serial8250_release_port(struct uart_port *port) | |
2768 | { | |
2769 | struct uart_8250_port *up = up_to_u8250p(port); | |
2770 | ||
2771 | serial8250_release_std_resource(up); | |
2772 | } | |
2773 | ||
2774 | static int serial8250_request_port(struct uart_port *port) | |
2775 | { | |
2776 | struct uart_8250_port *up = up_to_u8250p(port); | |
b6830f6d | 2777 | |
e4fda3a0 | 2778 | return serial8250_request_std_resource(up); |
b6830f6d PH |
2779 | } |
2780 | ||
2781 | static int fcr_get_rxtrig_bytes(struct uart_8250_port *up) | |
2782 | { | |
2783 | const struct serial8250_config *conf_type = &uart_config[up->port.type]; | |
2784 | unsigned char bytes; | |
2785 | ||
2786 | bytes = conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(up->fcr)]; | |
2787 | ||
2788 | return bytes ? bytes : -EOPNOTSUPP; | |
2789 | } | |
2790 | ||
2791 | static int bytes_to_fcr_rxtrig(struct uart_8250_port *up, unsigned char bytes) | |
2792 | { | |
2793 | const struct serial8250_config *conf_type = &uart_config[up->port.type]; | |
2794 | int i; | |
2795 | ||
2796 | if (!conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(UART_FCR_R_TRIG_00)]) | |
2797 | return -EOPNOTSUPP; | |
2798 | ||
2799 | for (i = 1; i < UART_FCR_R_TRIG_MAX_STATE; i++) { | |
2800 | if (bytes < conf_type->rxtrig_bytes[i]) | |
2801 | /* Use the nearest lower value */ | |
2802 | return (--i) << UART_FCR_R_TRIG_SHIFT; | |
2803 | } | |
2804 | ||
2805 | return UART_FCR_R_TRIG_11; | |
2806 | } | |
2807 | ||
2808 | static int do_get_rxtrig(struct tty_port *port) | |
2809 | { | |
2810 | struct uart_state *state = container_of(port, struct uart_state, port); | |
2811 | struct uart_port *uport = state->uart_port; | |
013e3586 | 2812 | struct uart_8250_port *up = up_to_u8250p(uport); |
b6830f6d PH |
2813 | |
2814 | if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1) | |
2815 | return -EINVAL; | |
2816 | ||
2817 | return fcr_get_rxtrig_bytes(up); | |
2818 | } | |
2819 | ||
2820 | static int do_serial8250_get_rxtrig(struct tty_port *port) | |
2821 | { | |
2822 | int rxtrig_bytes; | |
2823 | ||
2824 | mutex_lock(&port->mutex); | |
2825 | rxtrig_bytes = do_get_rxtrig(port); | |
2826 | mutex_unlock(&port->mutex); | |
2827 | ||
2828 | return rxtrig_bytes; | |
2829 | } | |
2830 | ||
2831 | static ssize_t serial8250_get_attr_rx_trig_bytes(struct device *dev, | |
2832 | struct device_attribute *attr, char *buf) | |
2833 | { | |
2834 | struct tty_port *port = dev_get_drvdata(dev); | |
2835 | int rxtrig_bytes; | |
2836 | ||
2837 | rxtrig_bytes = do_serial8250_get_rxtrig(port); | |
2838 | if (rxtrig_bytes < 0) | |
2839 | return rxtrig_bytes; | |
2840 | ||
2841 | return snprintf(buf, PAGE_SIZE, "%d\n", rxtrig_bytes); | |
2842 | } | |
2843 | ||
2844 | static int do_set_rxtrig(struct tty_port *port, unsigned char bytes) | |
2845 | { | |
2846 | struct uart_state *state = container_of(port, struct uart_state, port); | |
2847 | struct uart_port *uport = state->uart_port; | |
013e3586 | 2848 | struct uart_8250_port *up = up_to_u8250p(uport); |
b6830f6d PH |
2849 | int rxtrig; |
2850 | ||
2851 | if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1 || | |
2852 | up->fifo_bug) | |
2853 | return -EINVAL; | |
2854 | ||
2855 | rxtrig = bytes_to_fcr_rxtrig(up, bytes); | |
2856 | if (rxtrig < 0) | |
2857 | return rxtrig; | |
2858 | ||
2859 | serial8250_clear_fifos(up); | |
2860 | up->fcr &= ~UART_FCR_TRIGGER_MASK; | |
2861 | up->fcr |= (unsigned char)rxtrig; | |
2862 | serial_out(up, UART_FCR, up->fcr); | |
2863 | return 0; | |
2864 | } | |
2865 | ||
2866 | static int do_serial8250_set_rxtrig(struct tty_port *port, unsigned char bytes) | |
2867 | { | |
2868 | int ret; | |
2869 | ||
2870 | mutex_lock(&port->mutex); | |
2871 | ret = do_set_rxtrig(port, bytes); | |
2872 | mutex_unlock(&port->mutex); | |
2873 | ||
2874 | return ret; | |
2875 | } | |
2876 | ||
2877 | static ssize_t serial8250_set_attr_rx_trig_bytes(struct device *dev, | |
2878 | struct device_attribute *attr, const char *buf, size_t count) | |
2879 | { | |
2880 | struct tty_port *port = dev_get_drvdata(dev); | |
2881 | unsigned char bytes; | |
2882 | int ret; | |
2883 | ||
2884 | if (!count) | |
2885 | return -EINVAL; | |
2886 | ||
2887 | ret = kstrtou8(buf, 10, &bytes); | |
2888 | if (ret < 0) | |
2889 | return ret; | |
2890 | ||
2891 | ret = do_serial8250_set_rxtrig(port, bytes); | |
2892 | if (ret < 0) | |
2893 | return ret; | |
2894 | ||
2895 | return count; | |
2896 | } | |
2897 | ||
2898 | static DEVICE_ATTR(rx_trig_bytes, S_IRUSR | S_IWUSR | S_IRGRP, | |
2899 | serial8250_get_attr_rx_trig_bytes, | |
2900 | serial8250_set_attr_rx_trig_bytes); | |
2901 | ||
2902 | static struct attribute *serial8250_dev_attrs[] = { | |
2903 | &dev_attr_rx_trig_bytes.attr, | |
2904 | NULL, | |
2905 | }; | |
2906 | ||
2907 | static struct attribute_group serial8250_dev_attr_group = { | |
2908 | .attrs = serial8250_dev_attrs, | |
2909 | }; | |
2910 | ||
2911 | static void register_dev_spec_attr_grp(struct uart_8250_port *up) | |
2912 | { | |
2913 | const struct serial8250_config *conf_type = &uart_config[up->port.type]; | |
2914 | ||
2915 | if (conf_type->rxtrig_bytes[0]) | |
2916 | up->port.attr_group = &serial8250_dev_attr_group; | |
2917 | } | |
2918 | ||
2919 | static void serial8250_config_port(struct uart_port *port, int flags) | |
2920 | { | |
2921 | struct uart_8250_port *up = up_to_u8250p(port); | |
2922 | int ret; | |
2923 | ||
b6830f6d PH |
2924 | /* |
2925 | * Find the region that we can probe for. This in turn | |
2926 | * tells us whether we can probe for the type of port. | |
2927 | */ | |
2928 | ret = serial8250_request_std_resource(up); | |
2929 | if (ret < 0) | |
2930 | return; | |
2931 | ||
2932 | if (port->iotype != up->cur_iotype) | |
2933 | set_io_from_upio(port); | |
2934 | ||
2935 | if (flags & UART_CONFIG_TYPE) | |
2936 | autoconfig(up); | |
2937 | ||
2938 | /* if access method is AU, it is a 16550 with a quirk */ | |
2939 | if (port->type == PORT_16550A && port->iotype == UPIO_AU) | |
2940 | up->bugs |= UART_BUG_NOMSR; | |
2941 | ||
2942 | /* HW bugs may trigger IRQ while IIR == NO_INT */ | |
2943 | if (port->type == PORT_TEGRA) | |
2944 | up->bugs |= UART_BUG_NOMSR; | |
2945 | ||
2946 | if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ) | |
2947 | autoconfig_irq(up); | |
2948 | ||
2949 | if (port->type == PORT_UNKNOWN) | |
2950 | serial8250_release_std_resource(up); | |
2951 | ||
2952 | /* Fixme: probably not the best place for this */ | |
2953 | if ((port->type == PORT_XR17V35X) || | |
2954 | (port->type == PORT_XR17D15X)) | |
2955 | port->handle_irq = exar_handle_irq; | |
2956 | ||
2957 | register_dev_spec_attr_grp(up); | |
2958 | up->fcr = uart_config[up->port.type].fcr; | |
2959 | } | |
2960 | ||
2961 | static int | |
2962 | serial8250_verify_port(struct uart_port *port, struct serial_struct *ser) | |
2963 | { | |
2964 | if (ser->irq >= nr_irqs || ser->irq < 0 || | |
2965 | ser->baud_base < 9600 || ser->type < PORT_UNKNOWN || | |
2966 | ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS || | |
2967 | ser->type == PORT_STARTECH) | |
2968 | return -EINVAL; | |
2969 | return 0; | |
2970 | } | |
2971 | ||
cee10c8c | 2972 | static const char *serial8250_type(struct uart_port *port) |
b6830f6d PH |
2973 | { |
2974 | int type = port->type; | |
2975 | ||
2976 | if (type >= ARRAY_SIZE(uart_config)) | |
2977 | type = 0; | |
2978 | return uart_config[type].name; | |
2979 | } | |
2980 | ||
2981 | static const struct uart_ops serial8250_pops = { | |
2982 | .tx_empty = serial8250_tx_empty, | |
2983 | .set_mctrl = serial8250_set_mctrl, | |
2984 | .get_mctrl = serial8250_get_mctrl, | |
2985 | .stop_tx = serial8250_stop_tx, | |
2986 | .start_tx = serial8250_start_tx, | |
2987 | .throttle = serial8250_throttle, | |
2988 | .unthrottle = serial8250_unthrottle, | |
2989 | .stop_rx = serial8250_stop_rx, | |
2990 | .enable_ms = serial8250_enable_ms, | |
2991 | .break_ctl = serial8250_break_ctl, | |
2992 | .startup = serial8250_startup, | |
2993 | .shutdown = serial8250_shutdown, | |
2994 | .set_termios = serial8250_set_termios, | |
2995 | .set_ldisc = serial8250_set_ldisc, | |
2996 | .pm = serial8250_pm, | |
2997 | .type = serial8250_type, | |
2998 | .release_port = serial8250_release_port, | |
2999 | .request_port = serial8250_request_port, | |
3000 | .config_port = serial8250_config_port, | |
3001 | .verify_port = serial8250_verify_port, | |
3002 | #ifdef CONFIG_CONSOLE_POLL | |
3003 | .poll_get_char = serial8250_get_poll_char, | |
3004 | .poll_put_char = serial8250_put_poll_char, | |
3005 | #endif | |
3006 | }; | |
3007 | ||
3008 | void serial8250_init_port(struct uart_8250_port *up) | |
3009 | { | |
3010 | struct uart_port *port = &up->port; | |
3011 | ||
3012 | spin_lock_init(&port->lock); | |
3013 | port->ops = &serial8250_pops; | |
3014 | ||
3015 | up->cur_iotype = 0xFF; | |
3016 | } | |
3017 | EXPORT_SYMBOL_GPL(serial8250_init_port); | |
3018 | ||
3019 | void serial8250_set_defaults(struct uart_8250_port *up) | |
3020 | { | |
3021 | struct uart_port *port = &up->port; | |
3022 | ||
3023 | if (up->port.flags & UPF_FIXED_TYPE) { | |
3024 | unsigned int type = up->port.type; | |
3025 | ||
3026 | if (!up->port.fifosize) | |
3027 | up->port.fifosize = uart_config[type].fifo_size; | |
3028 | if (!up->tx_loadsz) | |
3029 | up->tx_loadsz = uart_config[type].tx_loadsz; | |
3030 | if (!up->capabilities) | |
3031 | up->capabilities = uart_config[type].flags; | |
3032 | } | |
3033 | ||
3034 | set_io_from_upio(port); | |
3035 | ||
3036 | /* default dma handlers */ | |
3037 | if (up->dma) { | |
3038 | if (!up->dma->tx_dma) | |
3039 | up->dma->tx_dma = serial8250_tx_dma; | |
3040 | if (!up->dma->rx_dma) | |
3041 | up->dma->rx_dma = serial8250_rx_dma; | |
3042 | } | |
3043 | } | |
3044 | EXPORT_SYMBOL_GPL(serial8250_set_defaults); | |
3045 | ||
3046 | #ifdef CONFIG_SERIAL_8250_CONSOLE | |
3047 | ||
3048 | static void serial8250_console_putchar(struct uart_port *port, int ch) | |
3049 | { | |
3050 | struct uart_8250_port *up = up_to_u8250p(port); | |
3051 | ||
3052 | wait_for_xmitr(up, UART_LSR_THRE); | |
3053 | serial_port_out(port, UART_TX, ch); | |
3054 | } | |
3055 | ||
10791233 PH |
3056 | /* |
3057 | * Restore serial console when h/w power-off detected | |
3058 | */ | |
3059 | static void serial8250_console_restore(struct uart_8250_port *up) | |
3060 | { | |
3061 | struct uart_port *port = &up->port; | |
3062 | struct ktermios termios; | |
3063 | unsigned int baud, quot, frac = 0; | |
3064 | ||
3065 | termios.c_cflag = port->cons->cflag; | |
3066 | if (port->state->port.tty && termios.c_cflag == 0) | |
3067 | termios.c_cflag = port->state->port.tty->termios.c_cflag; | |
3068 | ||
3069 | baud = serial8250_get_baud_rate(port, &termios, NULL); | |
3070 | quot = serial8250_get_divisor(up, baud, &frac); | |
3071 | ||
3072 | serial8250_set_divisor(port, baud, quot, frac); | |
3073 | serial_port_out(port, UART_LCR, up->lcr); | |
3074 | serial_port_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS); | |
3075 | } | |
3076 | ||
b6830f6d PH |
3077 | /* |
3078 | * Print a string to the serial port trying not to disturb | |
3079 | * any possible real use of the port... | |
3080 | * | |
3081 | * The console_lock must be held when we get here. | |
3082 | */ | |
3083 | void serial8250_console_write(struct uart_8250_port *up, const char *s, | |
3084 | unsigned int count) | |
3085 | { | |
3086 | struct uart_port *port = &up->port; | |
3087 | unsigned long flags; | |
3088 | unsigned int ier; | |
3089 | int locked = 1; | |
3090 | ||
3091 | touch_nmi_watchdog(); | |
3092 | ||
3093 | serial8250_rpm_get(up); | |
3094 | ||
3095 | if (port->sysrq) | |
3096 | locked = 0; | |
3097 | else if (oops_in_progress) | |
3098 | locked = spin_trylock_irqsave(&port->lock, flags); | |
3099 | else | |
3100 | spin_lock_irqsave(&port->lock, flags); | |
3101 | ||
3102 | /* | |
3103 | * First save the IER then disable the interrupts | |
3104 | */ | |
3105 | ier = serial_port_in(port, UART_IER); | |
3106 | ||
3107 | if (up->capabilities & UART_CAP_UUE) | |
3108 | serial_port_out(port, UART_IER, UART_IER_UUE); | |
3109 | else | |
3110 | serial_port_out(port, UART_IER, 0); | |
3111 | ||
3112 | /* check scratch reg to see if port powered off during system sleep */ | |
3113 | if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) { | |
10791233 | 3114 | serial8250_console_restore(up); |
b6830f6d PH |
3115 | up->canary = 0; |
3116 | } | |
3117 | ||
3118 | uart_console_write(port, s, count, serial8250_console_putchar); | |
3119 | ||
3120 | /* | |
3121 | * Finally, wait for transmitter to become empty | |
3122 | * and restore the IER | |
3123 | */ | |
3124 | wait_for_xmitr(up, BOTH_EMPTY); | |
3125 | serial_port_out(port, UART_IER, ier); | |
3126 | ||
3127 | /* | |
3128 | * The receive handling will happen properly because the | |
3129 | * receive ready bit will still be set; it is not cleared | |
3130 | * on read. However, modem control will not, we must | |
3131 | * call it if we have saved something in the saved flags | |
3132 | * while processing with interrupts off. | |
3133 | */ | |
3134 | if (up->msr_saved_flags) | |
3135 | serial8250_modem_status(up); | |
3136 | ||
3137 | if (locked) | |
3138 | spin_unlock_irqrestore(&port->lock, flags); | |
3139 | serial8250_rpm_put(up); | |
3140 | } | |
3141 | ||
3142 | static unsigned int probe_baud(struct uart_port *port) | |
3143 | { | |
3144 | unsigned char lcr, dll, dlm; | |
3145 | unsigned int quot; | |
3146 | ||
3147 | lcr = serial_port_in(port, UART_LCR); | |
3148 | serial_port_out(port, UART_LCR, lcr | UART_LCR_DLAB); | |
3149 | dll = serial_port_in(port, UART_DLL); | |
3150 | dlm = serial_port_in(port, UART_DLM); | |
3151 | serial_port_out(port, UART_LCR, lcr); | |
3152 | ||
3153 | quot = (dlm << 8) | dll; | |
3154 | return (port->uartclk / 16) / quot; | |
3155 | } | |
3156 | ||
3157 | int serial8250_console_setup(struct uart_port *port, char *options, bool probe) | |
3158 | { | |
3159 | int baud = 9600; | |
3160 | int bits = 8; | |
3161 | int parity = 'n'; | |
3162 | int flow = 'n'; | |
3163 | ||
3164 | if (!port->iobase && !port->membase) | |
3165 | return -ENODEV; | |
3166 | ||
3167 | if (options) | |
3168 | uart_parse_options(options, &baud, &parity, &bits, &flow); | |
3169 | else if (probe) | |
3170 | baud = probe_baud(port); | |
3171 | ||
3172 | return uart_set_options(port, port->cons, baud, parity, bits, flow); | |
3173 | } | |
3174 | ||
3175 | #endif /* CONFIG_SERIAL_8250_CONSOLE */ | |
f7a7651f JM |
3176 | |
3177 | MODULE_LICENSE("GPL"); |