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PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / tty / serial / sunsab.c
blob380fb5355cb26ae68a472a4e6097c57556d0b8e1
1 /* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
2 *
3 * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
4 * Copyright (C) 2002, 2006 David S. Miller (davem@davemloft.net)
5 *
6 * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
7 * Maxim Krasnyanskiy <maxk@qualcomm.com>
8 *
9 * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
10 * rates to be programmed into the UART. Also eliminated a lot of
11 * duplicated code in the console setup.
12 * Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
13 *
14 * Ported to new 2.5.x UART layer.
15 * David S. Miller <davem@davemloft.net>
16 */
17
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/errno.h>
21 #include <linux/tty.h>
22 #include <linux/tty_flip.h>
23 #include <linux/major.h>
24 #include <linux/string.h>
25 #include <linux/ptrace.h>
26 #include <linux/ioport.h>
27 #include <linux/circ_buf.h>
28 #include <linux/serial.h>
29 #include <linux/sysrq.h>
30 #include <linux/console.h>
31 #include <linux/spinlock.h>
32 #include <linux/slab.h>
33 #include <linux/delay.h>
34 #include <linux/init.h>
35 #include <linux/of_device.h>
36
37 #include <asm/io.h>
38 #include <asm/irq.h>
39 #include <asm/prom.h>
40 #include <asm/setup.h>
41
42 #if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
43 #define SUPPORT_SYSRQ
44 #endif
45
46 #include <linux/serial_core.h>
47 #include <linux/sunserialcore.h>
48
49 #include "sunsab.h"
50
51 struct uart_sunsab_port {
52 struct uart_port port; /* Generic UART port */
53 union sab82532_async_regs __iomem *regs; /* Chip registers */
54 unsigned long irqflags; /* IRQ state flags */
55 int dsr; /* Current DSR state */
56 unsigned int cec_timeout; /* Chip poll timeout... */
57 unsigned int tec_timeout; /* likewise */
58 unsigned char interrupt_mask0;/* ISR0 masking */
59 unsigned char interrupt_mask1;/* ISR1 masking */
60 unsigned char pvr_dtr_bit; /* Which PVR bit is DTR */
61 unsigned char pvr_dsr_bit; /* Which PVR bit is DSR */
62 unsigned int gis_shift;
63 int type; /* SAB82532 version */
64
65 /* Setting configuration bits while the transmitter is active
66 * can cause garbage characters to get emitted by the chip.
67 * Therefore, we cache such writes here and do the real register
68 * write the next time the transmitter becomes idle.
69 */
70 unsigned int cached_ebrg;
71 unsigned char cached_mode;
72 unsigned char cached_pvr;
73 unsigned char cached_dafo;
74 };
75
76 /*
77 * This assumes you have a 29.4912 MHz clock for your UART.
78 */
79 #define SAB_BASE_BAUD ( 29491200 / 16 )
80
81 static char *sab82532_version[16] = {
82 "V1.0", "V2.0", "V3.2", "V(0x03)",
83 "V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
84 "V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
85 "V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
86 };
87
88 #define SAB82532_MAX_TEC_TIMEOUT 200000 /* 1 character time (at 50 baud) */
89 #define SAB82532_MAX_CEC_TIMEOUT 50000 /* 2.5 TX CLKs (at 50 baud) */
90
91 #define SAB82532_RECV_FIFO_SIZE 32 /* Standard async fifo sizes */
92 #define SAB82532_XMIT_FIFO_SIZE 32
93
94 static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
95 {
96 int timeout = up->tec_timeout;
97
98 while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
99 udelay(1);
100 }
101
102 static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
103 {
104 int timeout = up->cec_timeout;
105
106 while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
107 udelay(1);
108 }
109
110 static struct tty_port *
111 receive_chars(struct uart_sunsab_port *up,
112 union sab82532_irq_status *stat)
113 {
114 struct tty_port *port = NULL;
115 unsigned char buf[32];
116 int saw_console_brk = 0;
117 int free_fifo = 0;
118 int count = 0;
119 int i;
120
121 if (up->port.state != NULL) /* Unopened serial console */
122 port = &up->port.state->port;
123
124 /* Read number of BYTES (Character + Status) available. */
125 if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
126 count = SAB82532_RECV_FIFO_SIZE;
127 free_fifo++;
128 }
129
130 if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
131 count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
132 free_fifo++;
133 }
134
135 /* Issue a FIFO read command in case we where idle. */
136 if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
137 sunsab_cec_wait(up);
138 writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
139 return port;
140 }
141
142 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
143 free_fifo++;
144
145 /* Read the FIFO. */
146 for (i = 0; i < count; i++)
147 buf[i] = readb(&up->regs->r.rfifo[i]);
148
149 /* Issue Receive Message Complete command. */
150 if (free_fifo) {
151 sunsab_cec_wait(up);
152 writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
153 }
154
155 /* Count may be zero for BRK, so we check for it here */
156 if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
157 (up->port.line == up->port.cons->index))
158 saw_console_brk = 1;
159
160 for (i = 0; i < count; i++) {
161 unsigned char ch = buf[i], flag;
162
163 flag = TTY_NORMAL;
164 up->port.icount.rx++;
165
166 if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
167 SAB82532_ISR0_FERR |
168 SAB82532_ISR0_RFO)) ||
169 unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
170 /*
171 * For statistics only
172 */
173 if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
174 stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
175 SAB82532_ISR0_FERR);
176 up->port.icount.brk++;
177 /*
178 * We do the SysRQ and SAK checking
179 * here because otherwise the break
180 * may get masked by ignore_status_mask
181 * or read_status_mask.
182 */
183 if (uart_handle_break(&up->port))
184 continue;
185 } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
186 up->port.icount.parity++;
187 else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
188 up->port.icount.frame++;
189 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
190 up->port.icount.overrun++;
191
192 /*
193 * Mask off conditions which should be ingored.
194 */
195 stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
196 stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
197
198 if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
199 flag = TTY_BREAK;
200 } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
201 flag = TTY_PARITY;
202 else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
203 flag = TTY_FRAME;
204 }
205
206 if (uart_handle_sysrq_char(&up->port, ch) || !port)
207 continue;
208
209 if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
210 (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
211 tty_insert_flip_char(port, ch, flag);
212 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
213 tty_insert_flip_char(port, 0, TTY_OVERRUN);
214 }
215
216 if (saw_console_brk)
217 sun_do_break();
218
219 return port;
220 }
221
222 static void sunsab_stop_tx(struct uart_port *);
223 static void sunsab_tx_idle(struct uart_sunsab_port *);
224
225 static void transmit_chars(struct uart_sunsab_port *up,
226 union sab82532_irq_status *stat)
227 {
228 struct circ_buf *xmit = &up->port.state->xmit;
229 int i;
230
231 if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
232 up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
233 writeb(up->interrupt_mask1, &up->regs->w.imr1);
234 set_bit(SAB82532_ALLS, &up->irqflags);
235 }
236
237 #if 0 /* bde@nwlink.com says this check causes problems */
238 if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
239 return;
240 #endif
241
242 if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
243 return;
244
245 set_bit(SAB82532_XPR, &up->irqflags);
246 sunsab_tx_idle(up);
247
248 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
249 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
250 writeb(up->interrupt_mask1, &up->regs->w.imr1);
251 return;
252 }
253
254 up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
255 writeb(up->interrupt_mask1, &up->regs->w.imr1);
256 clear_bit(SAB82532_ALLS, &up->irqflags);
257
258 /* Stuff 32 bytes into Transmit FIFO. */
259 clear_bit(SAB82532_XPR, &up->irqflags);
260 for (i = 0; i < up->port.fifosize; i++) {
261 writeb(xmit->buf[xmit->tail],
262 &up->regs->w.xfifo[i]);
263 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
264 up->port.icount.tx++;
265 if (uart_circ_empty(xmit))
266 break;
267 }
268
269 /* Issue a Transmit Frame command. */
270 sunsab_cec_wait(up);
271 writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
272
273 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
274 uart_write_wakeup(&up->port);
275
276 if (uart_circ_empty(xmit))
277 sunsab_stop_tx(&up->port);
278 }
279
280 static void check_status(struct uart_sunsab_port *up,
281 union sab82532_irq_status *stat)
282 {
283 if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
284 uart_handle_dcd_change(&up->port,
285 !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
286
287 if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
288 uart_handle_cts_change(&up->port,
289 (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
290
291 if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
292 up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
293 up->port.icount.dsr++;
294 }
295
296 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
297 }
298
299 static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
300 {
301 struct uart_sunsab_port *up = dev_id;
302 struct tty_port *port = NULL;
303 union sab82532_irq_status status;
304 unsigned long flags;
305 unsigned char gis;
306
307 spin_lock_irqsave(&up->port.lock, flags);
308
309 status.stat = 0;
310 gis = readb(&up->regs->r.gis) >> up->gis_shift;
311 if (gis & 1)
312 status.sreg.isr0 = readb(&up->regs->r.isr0);
313 if (gis & 2)
314 status.sreg.isr1 = readb(&up->regs->r.isr1);
315
316 if (status.stat) {
317 if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
318 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
319 (status.sreg.isr1 & SAB82532_ISR1_BRK))
320 port = receive_chars(up, &status);
321 if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
322 (status.sreg.isr1 & SAB82532_ISR1_CSC))
323 check_status(up, &status);
324 if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
325 transmit_chars(up, &status);
326 }
327
328 spin_unlock_irqrestore(&up->port.lock, flags);
329
330 if (port)
331 tty_flip_buffer_push(port);
332
333 return IRQ_HANDLED;
334 }
335
336 /* port->lock is not held. */
337 static unsigned int sunsab_tx_empty(struct uart_port *port)
338 {
339 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
340 int ret;
341
342 /* Do not need a lock for a state test like this. */
343 if (test_bit(SAB82532_ALLS, &up->irqflags))
344 ret = TIOCSER_TEMT;
345 else
346 ret = 0;
347
348 return ret;
349 }
350
351 /* port->lock held by caller. */
352 static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
353 {
354 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
355
356 if (mctrl & TIOCM_RTS) {
357 up->cached_mode &= ~SAB82532_MODE_FRTS;
358 up->cached_mode |= SAB82532_MODE_RTS;
359 } else {
360 up->cached_mode |= (SAB82532_MODE_FRTS |
361 SAB82532_MODE_RTS);
362 }
363 if (mctrl & TIOCM_DTR) {
364 up->cached_pvr &= ~(up->pvr_dtr_bit);
365 } else {
366 up->cached_pvr |= up->pvr_dtr_bit;
367 }
368
369 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
370 if (test_bit(SAB82532_XPR, &up->irqflags))
371 sunsab_tx_idle(up);
372 }
373
374 /* port->lock is held by caller and interrupts are disabled. */
375 static unsigned int sunsab_get_mctrl(struct uart_port *port)
376 {
377 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
378 unsigned char val;
379 unsigned int result;
380
381 result = 0;
382
383 val = readb(&up->regs->r.pvr);
384 result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
385
386 val = readb(&up->regs->r.vstr);
387 result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
388
389 val = readb(&up->regs->r.star);
390 result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
391
392 return result;
393 }
394
395 /* port->lock held by caller. */
396 static void sunsab_stop_tx(struct uart_port *port)
397 {
398 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
399
400 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
401 writeb(up->interrupt_mask1, &up->regs->w.imr1);
402 }
403
404 /* port->lock held by caller. */
405 static void sunsab_tx_idle(struct uart_sunsab_port *up)
406 {
407 if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
408 u8 tmp;
409
410 clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
411 writeb(up->cached_mode, &up->regs->rw.mode);
412 writeb(up->cached_pvr, &up->regs->rw.pvr);
413 writeb(up->cached_dafo, &up->regs->w.dafo);
414
415 writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
416 tmp = readb(&up->regs->rw.ccr2);
417 tmp &= ~0xc0;
418 tmp |= (up->cached_ebrg >> 2) & 0xc0;
419 writeb(tmp, &up->regs->rw.ccr2);
420 }
421 }
422
423 /* port->lock held by caller. */
424 static void sunsab_start_tx(struct uart_port *port)
425 {
426 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
427 struct circ_buf *xmit = &up->port.state->xmit;
428 int i;
429
430 up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
431 writeb(up->interrupt_mask1, &up->regs->w.imr1);
432
433 if (!test_bit(SAB82532_XPR, &up->irqflags))
434 return;
435
436 clear_bit(SAB82532_ALLS, &up->irqflags);
437 clear_bit(SAB82532_XPR, &up->irqflags);
438
439 for (i = 0; i < up->port.fifosize; i++) {
440 writeb(xmit->buf[xmit->tail],
441 &up->regs->w.xfifo[i]);
442 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
443 up->port.icount.tx++;
444 if (uart_circ_empty(xmit))
445 break;
446 }
447
448 /* Issue a Transmit Frame command. */
449 sunsab_cec_wait(up);
450 writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
451 }
452
453 /* port->lock is not held. */
454 static void sunsab_send_xchar(struct uart_port *port, char ch)
455 {
456 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
457 unsigned long flags;
458
459 spin_lock_irqsave(&up->port.lock, flags);
460
461 sunsab_tec_wait(up);
462 writeb(ch, &up->regs->w.tic);
463
464 spin_unlock_irqrestore(&up->port.lock, flags);
465 }
466
467 /* port->lock held by caller. */
468 static void sunsab_stop_rx(struct uart_port *port)
469 {
470 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
471
472 up->interrupt_mask0 |= SAB82532_IMR0_TCD;
473 writeb(up->interrupt_mask1, &up->regs->w.imr0);
474 }
475
476 /* port->lock held by caller. */
477 static void sunsab_enable_ms(struct uart_port *port)
478 {
479 /* For now we always receive these interrupts. */
480 }
481
482 /* port->lock is not held. */
483 static void sunsab_break_ctl(struct uart_port *port, int break_state)
484 {
485 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
486 unsigned long flags;
487 unsigned char val;
488
489 spin_lock_irqsave(&up->port.lock, flags);
490
491 val = up->cached_dafo;
492 if (break_state)
493 val |= SAB82532_DAFO_XBRK;
494 else
495 val &= ~SAB82532_DAFO_XBRK;
496 up->cached_dafo = val;
497
498 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
499 if (test_bit(SAB82532_XPR, &up->irqflags))
500 sunsab_tx_idle(up);
501
502 spin_unlock_irqrestore(&up->port.lock, flags);
503 }
504
505 /* port->lock is not held. */
506 static int sunsab_startup(struct uart_port *port)
507 {
508 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
509 unsigned long flags;
510 unsigned char tmp;
511 int err = request_irq(up->port.irq, sunsab_interrupt,
512 IRQF_SHARED, "sab", up);
513 if (err)
514 return err;
515
516 spin_lock_irqsave(&up->port.lock, flags);
517
518 /*
519 * Wait for any commands or immediate characters
520 */
521 sunsab_cec_wait(up);
522 sunsab_tec_wait(up);
523
524 /*
525 * Clear the FIFO buffers.
526 */
527 writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
528 sunsab_cec_wait(up);
529 writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
530
531 /*
532 * Clear the interrupt registers.
533 */
534 (void) readb(&up->regs->r.isr0);
535 (void) readb(&up->regs->r.isr1);
536
537 /*
538 * Now, initialize the UART
539 */
540 writeb(0, &up->regs->w.ccr0); /* power-down */
541 writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
542 SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
543 writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
544 writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
545 SAB82532_CCR2_TOE, &up->regs->w.ccr2);
546 writeb(0, &up->regs->w.ccr3);
547 writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
548 up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
549 SAB82532_MODE_RAC);
550 writeb(up->cached_mode, &up->regs->w.mode);
551 writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
552
553 tmp = readb(&up->regs->rw.ccr0);
554 tmp |= SAB82532_CCR0_PU; /* power-up */
555 writeb(tmp, &up->regs->rw.ccr0);
556
557 /*
558 * Finally, enable interrupts
559 */
560 up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
561 SAB82532_IMR0_PLLA);
562 writeb(up->interrupt_mask0, &up->regs->w.imr0);
563 up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
564 SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
565 SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
566 SAB82532_IMR1_XPR);
567 writeb(up->interrupt_mask1, &up->regs->w.imr1);
568 set_bit(SAB82532_ALLS, &up->irqflags);
569 set_bit(SAB82532_XPR, &up->irqflags);
570
571 spin_unlock_irqrestore(&up->port.lock, flags);
572
573 return 0;
574 }
575
576 /* port->lock is not held. */
577 static void sunsab_shutdown(struct uart_port *port)
578 {
579 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
580 unsigned long flags;
581
582 spin_lock_irqsave(&up->port.lock, flags);
583
584 /* Disable Interrupts */
585 up->interrupt_mask0 = 0xff;
586 writeb(up->interrupt_mask0, &up->regs->w.imr0);
587 up->interrupt_mask1 = 0xff;
588 writeb(up->interrupt_mask1, &up->regs->w.imr1);
589
590 /* Disable break condition */
591 up->cached_dafo = readb(&up->regs->rw.dafo);
592 up->cached_dafo &= ~SAB82532_DAFO_XBRK;
593 writeb(up->cached_dafo, &up->regs->rw.dafo);
594
595 /* Disable Receiver */
596 up->cached_mode &= ~SAB82532_MODE_RAC;
597 writeb(up->cached_mode, &up->regs->rw.mode);
598
599 /*
600 * XXX FIXME
601 *
602 * If the chip is powered down here the system hangs/crashes during
603 * reboot or shutdown. This needs to be investigated further,
604 * similar behaviour occurs in 2.4 when the driver is configured
605 * as a module only. One hint may be that data is sometimes
606 * transmitted at 9600 baud during shutdown (regardless of the
607 * speed the chip was configured for when the port was open).
608 */
609 #if 0
610 /* Power Down */
611 tmp = readb(&up->regs->rw.ccr0);
612 tmp &= ~SAB82532_CCR0_PU;
613 writeb(tmp, &up->regs->rw.ccr0);
614 #endif
615
616 spin_unlock_irqrestore(&up->port.lock, flags);
617 free_irq(up->port.irq, up);
618 }
619
620 /*
621 * This is used to figure out the divisor speeds.
622 *
623 * The formula is: Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
624 *
625 * with 0 <= N < 64 and 0 <= M < 16
626 */
627
628 static void calc_ebrg(int baud, int *n_ret, int *m_ret)
629 {
630 int n, m;
631
632 if (baud == 0) {
633 *n_ret = 0;
634 *m_ret = 0;
635 return;
636 }
637
638 /*
639 * We scale numbers by 10 so that we get better accuracy
640 * without having to use floating point. Here we increment m
641 * until n is within the valid range.
642 */
643 n = (SAB_BASE_BAUD * 10) / baud;
644 m = 0;
645 while (n >= 640) {
646 n = n / 2;
647 m++;
648 }
649 n = (n+5) / 10;
650 /*
651 * We try very hard to avoid speeds with M == 0 since they may
652 * not work correctly for XTAL frequences above 10 MHz.
653 */
654 if ((m == 0) && ((n & 1) == 0)) {
655 n = n / 2;
656 m++;
657 }
658 *n_ret = n - 1;
659 *m_ret = m;
660 }
661
662 /* Internal routine, port->lock is held and local interrupts are disabled. */
663 static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
664 unsigned int iflag, unsigned int baud,
665 unsigned int quot)
666 {
667 unsigned char dafo;
668 int bits, n, m;
669
670 /* Byte size and parity */
671 switch (cflag & CSIZE) {
672 case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
673 case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
674 case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
675 case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
676 /* Never happens, but GCC is too dumb to figure it out */
677 default: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
678 }
679
680 if (cflag & CSTOPB) {
681 dafo |= SAB82532_DAFO_STOP;
682 bits++;
683 }
684
685 if (cflag & PARENB) {
686 dafo |= SAB82532_DAFO_PARE;
687 bits++;
688 }
689
690 if (cflag & PARODD) {
691 dafo |= SAB82532_DAFO_PAR_ODD;
692 } else {
693 dafo |= SAB82532_DAFO_PAR_EVEN;
694 }
695 up->cached_dafo = dafo;
696
697 calc_ebrg(baud, &n, &m);
698
699 up->cached_ebrg = n | (m << 6);
700
701 up->tec_timeout = (10 * 1000000) / baud;
702 up->cec_timeout = up->tec_timeout >> 2;
703
704 /* CTS flow control flags */
705 /* We encode read_status_mask and ignore_status_mask like so:
706 *
707 * ---------------------
708 * | ... | ISR1 | ISR0 |
709 * ---------------------
710 * .. 15 8 7 0
711 */
712
713 up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
714 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
715 SAB82532_ISR0_CDSC);
716 up->port.read_status_mask |= (SAB82532_ISR1_CSC |
717 SAB82532_ISR1_ALLS |
718 SAB82532_ISR1_XPR) << 8;
719 if (iflag & INPCK)
720 up->port.read_status_mask |= (SAB82532_ISR0_PERR |
721 SAB82532_ISR0_FERR);
722 if (iflag & (BRKINT | PARMRK))
723 up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
724
725 /*
726 * Characteres to ignore
727 */
728 up->port.ignore_status_mask = 0;
729 if (iflag & IGNPAR)
730 up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
731 SAB82532_ISR0_FERR);
732 if (iflag & IGNBRK) {
733 up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
734 /*
735 * If we're ignoring parity and break indicators,
736 * ignore overruns too (for real raw support).
737 */
738 if (iflag & IGNPAR)
739 up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
740 }
741
742 /*
743 * ignore all characters if CREAD is not set
744 */
745 if ((cflag & CREAD) == 0)
746 up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
747 SAB82532_ISR0_TCD);
748
749 uart_update_timeout(&up->port, cflag,
750 (up->port.uartclk / (16 * quot)));
751
752 /* Now schedule a register update when the chip's
753 * transmitter is idle.
754 */
755 up->cached_mode |= SAB82532_MODE_RAC;
756 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
757 if (test_bit(SAB82532_XPR, &up->irqflags))
758 sunsab_tx_idle(up);
759 }
760
761 /* port->lock is not held. */
762 static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
763 struct ktermios *old)
764 {
765 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
766 unsigned long flags;
767 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
768 unsigned int quot = uart_get_divisor(port, baud);
769
770 spin_lock_irqsave(&up->port.lock, flags);
771 sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
772 spin_unlock_irqrestore(&up->port.lock, flags);
773 }
774
775 static const char *sunsab_type(struct uart_port *port)
776 {
777 struct uart_sunsab_port *up = (void *)port;
778 static char buf[36];
779
780 sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
781 return buf;
782 }
783
784 static void sunsab_release_port(struct uart_port *port)
785 {
786 }
787
788 static int sunsab_request_port(struct uart_port *port)
789 {
790 return 0;
791 }
792
793 static void sunsab_config_port(struct uart_port *port, int flags)
794 {
795 }
796
797 static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
798 {
799 return -EINVAL;
800 }
801
802 static struct uart_ops sunsab_pops = {
803 .tx_empty = sunsab_tx_empty,
804 .set_mctrl = sunsab_set_mctrl,
805 .get_mctrl = sunsab_get_mctrl,
806 .stop_tx = sunsab_stop_tx,
807 .start_tx = sunsab_start_tx,
808 .send_xchar = sunsab_send_xchar,
809 .stop_rx = sunsab_stop_rx,
810 .enable_ms = sunsab_enable_ms,
811 .break_ctl = sunsab_break_ctl,
812 .startup = sunsab_startup,
813 .shutdown = sunsab_shutdown,
814 .set_termios = sunsab_set_termios,
815 .type = sunsab_type,
816 .release_port = sunsab_release_port,
817 .request_port = sunsab_request_port,
818 .config_port = sunsab_config_port,
819 .verify_port = sunsab_verify_port,
820 };
821
822 static struct uart_driver sunsab_reg = {
823 .owner = THIS_MODULE,
824 .driver_name = "sunsab",
825 .dev_name = "ttyS",
826 .major = TTY_MAJOR,
827 };
828
829 static struct uart_sunsab_port *sunsab_ports;
830
831 #ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
832
833 static void sunsab_console_putchar(struct uart_port *port, int c)
834 {
835 struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
836
837 sunsab_tec_wait(up);
838 writeb(c, &up->regs->w.tic);
839 }
840
841 static void sunsab_console_write(struct console *con, const char *s, unsigned n)
842 {
843 struct uart_sunsab_port *up = &sunsab_ports[con->index];
844 unsigned long flags;
845 int locked = 1;
846
847 local_irq_save(flags);
848 if (up->port.sysrq) {
849 locked = 0;
850 } else if (oops_in_progress) {
851 locked = spin_trylock(&up->port.lock);
852 } else
853 spin_lock(&up->port.lock);
854
855 uart_console_write(&up->port, s, n, sunsab_console_putchar);
856 sunsab_tec_wait(up);
857
858 if (locked)
859 spin_unlock(&up->port.lock);
860 local_irq_restore(flags);
861 }
862
863 static int sunsab_console_setup(struct console *con, char *options)
864 {
865 struct uart_sunsab_port *up = &sunsab_ports[con->index];
866 unsigned long flags;
867 unsigned int baud, quot;
868
869 /*
870 * The console framework calls us for each and every port
871 * registered. Defer the console setup until the requested
872 * port has been properly discovered. A bit of a hack,
873 * though...
874 */
875 if (up->port.type != PORT_SUNSAB)
876 return -1;
877
878 printk("Console: ttyS%d (SAB82532)\n",
879 (sunsab_reg.minor - 64) + con->index);
880
881 sunserial_console_termios(con, up->port.dev->of_node);
882
883 switch (con->cflag & CBAUD) {
884 case B150: baud = 150; break;
885 case B300: baud = 300; break;
886 case B600: baud = 600; break;
887 case B1200: baud = 1200; break;
888 case B2400: baud = 2400; break;
889 case B4800: baud = 4800; break;
890 default: case B9600: baud = 9600; break;
891 case B19200: baud = 19200; break;
892 case B38400: baud = 38400; break;
893 case B57600: baud = 57600; break;
894 case B115200: baud = 115200; break;
895 case B230400: baud = 230400; break;
896 case B460800: baud = 460800; break;
897 }
898
899 /*
900 * Temporary fix.
901 */
902 spin_lock_init(&up->port.lock);
903
904 /*
905 * Initialize the hardware
906 */
907 sunsab_startup(&up->port);
908
909 spin_lock_irqsave(&up->port.lock, flags);
910
911 /*
912 * Finally, enable interrupts
913 */
914 up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
915 SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
916 writeb(up->interrupt_mask0, &up->regs->w.imr0);
917 up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
918 SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
919 SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
920 SAB82532_IMR1_XPR;
921 writeb(up->interrupt_mask1, &up->regs->w.imr1);
922
923 quot = uart_get_divisor(&up->port, baud);
924 sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
925 sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
926
927 spin_unlock_irqrestore(&up->port.lock, flags);
928
929 return 0;
930 }
931
932 static struct console sunsab_console = {
933 .name = "ttyS",
934 .write = sunsab_console_write,
935 .device = uart_console_device,
936 .setup = sunsab_console_setup,
937 .flags = CON_PRINTBUFFER,
938 .index = -1,
939 .data = &sunsab_reg,
940 };
941
942 static inline struct console *SUNSAB_CONSOLE(void)
943 {
944 return &sunsab_console;
945 }
946 #else
947 #define SUNSAB_CONSOLE() (NULL)
948 #define sunsab_console_init() do { } while (0)
949 #endif
950
951 static int sunsab_init_one(struct uart_sunsab_port *up,
952 struct platform_device *op,
953 unsigned long offset,
954 int line)
955 {
956 up->port.line = line;
957 up->port.dev = &op->dev;
958
959 up->port.mapbase = op->resource[0].start + offset;
960 up->port.membase = of_ioremap(&op->resource[0], offset,
961 sizeof(union sab82532_async_regs),
962 "sab");
963 if (!up->port.membase)
964 return -ENOMEM;
965 up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
966
967 up->port.irq = op->archdata.irqs[0];
968
969 up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
970 up->port.iotype = UPIO_MEM;
971
972 writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
973
974 up->port.ops = &sunsab_pops;
975 up->port.type = PORT_SUNSAB;
976 up->port.uartclk = SAB_BASE_BAUD;
977
978 up->type = readb(&up->regs->r.vstr) & 0x0f;
979 writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
980 writeb(0xff, &up->regs->w.pim);
981 if ((up->port.line & 0x1) == 0) {
982 up->pvr_dsr_bit = (1 << 0);
983 up->pvr_dtr_bit = (1 << 1);
984 up->gis_shift = 2;
985 } else {
986 up->pvr_dsr_bit = (1 << 3);
987 up->pvr_dtr_bit = (1 << 2);
988 up->gis_shift = 0;
989 }
990 up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
991 writeb(up->cached_pvr, &up->regs->w.pvr);
992 up->cached_mode = readb(&up->regs->rw.mode);
993 up->cached_mode |= SAB82532_MODE_FRTS;
994 writeb(up->cached_mode, &up->regs->rw.mode);
995 up->cached_mode |= SAB82532_MODE_RTS;
996 writeb(up->cached_mode, &up->regs->rw.mode);
997
998 up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
999 up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1000
1001 return 0;
1002 }
1003
1004 static int sab_probe(struct platform_device *op)
1005 {
1006 static int inst;
1007 struct uart_sunsab_port *up;
1008 int err;
1009
1010 up = &sunsab_ports[inst * 2];
1011
1012 err = sunsab_init_one(&up[0], op,
1013 0,
1014 (inst * 2) + 0);
1015 if (err)
1016 goto out;
1017
1018 err = sunsab_init_one(&up[1], op,
1019 sizeof(union sab82532_async_regs),
1020 (inst * 2) + 1);
1021 if (err)
1022 goto out1;
1023
1024 sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1025 &sunsab_reg, up[0].port.line,
1026 false);
1027
1028 sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1029 &sunsab_reg, up[1].port.line,
1030 false);
1031
1032 err = uart_add_one_port(&sunsab_reg, &up[0].port);
1033 if (err)
1034 goto out2;
1035
1036 err = uart_add_one_port(&sunsab_reg, &up[1].port);
1037 if (err)
1038 goto out3;
1039
1040 platform_set_drvdata(op, &up[0]);
1041
1042 inst++;
1043
1044 return 0;
1045
1046 out3:
1047 uart_remove_one_port(&sunsab_reg, &up[0].port);
1048 out2:
1049 of_iounmap(&op->resource[0],
1050 up[1].port.membase,
1051 sizeof(union sab82532_async_regs));
1052 out1:
1053 of_iounmap(&op->resource[0],
1054 up[0].port.membase,
1055 sizeof(union sab82532_async_regs));
1056 out:
1057 return err;
1058 }
1059
1060 static int sab_remove(struct platform_device *op)
1061 {
1062 struct uart_sunsab_port *up = platform_get_drvdata(op);
1063
1064 uart_remove_one_port(&sunsab_reg, &up[1].port);
1065 uart_remove_one_port(&sunsab_reg, &up[0].port);
1066 of_iounmap(&op->resource[0],
1067 up[1].port.membase,
1068 sizeof(union sab82532_async_regs));
1069 of_iounmap(&op->resource[0],
1070 up[0].port.membase,
1071 sizeof(union sab82532_async_regs));
1072
1073 return 0;
1074 }
1075
1076 static const struct of_device_id sab_match[] = {
1077 {
1078 .name = "se",
1079 },
1080 {
1081 .name = "serial",
1082 .compatible = "sab82532",
1083 },
1084 {},
1085 };
1086 MODULE_DEVICE_TABLE(of, sab_match);
1087
1088 static struct platform_driver sab_driver = {
1089 .driver = {
1090 .name = "sab",
1091 .owner = THIS_MODULE,
1092 .of_match_table = sab_match,
1093 },
1094 .probe = sab_probe,
1095 .remove = sab_remove,
1096 };
1097
1098 static int __init sunsab_init(void)
1099 {
1100 struct device_node *dp;
1101 int err;
1102 int num_channels = 0;
1103
1104 for_each_node_by_name(dp, "se")
1105 num_channels += 2;
1106 for_each_node_by_name(dp, "serial") {
1107 if (of_device_is_compatible(dp, "sab82532"))
1108 num_channels += 2;
1109 }
1110
1111 if (num_channels) {
1112 sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1113 num_channels, GFP_KERNEL);
1114 if (!sunsab_ports)
1115 return -ENOMEM;
1116
1117 err = sunserial_register_minors(&sunsab_reg, num_channels);
1118 if (err) {
1119 kfree(sunsab_ports);
1120 sunsab_ports = NULL;
1121
1122 return err;
1123 }
1124 }
1125
1126 return platform_driver_register(&sab_driver);
1127 }
1128
1129 static void __exit sunsab_exit(void)
1130 {
1131 platform_driver_unregister(&sab_driver);
1132 if (sunsab_reg.nr) {
1133 sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1134 }
1135
1136 kfree(sunsab_ports);
1137 sunsab_ports = NULL;
1138 }
1139
1140 module_init(sunsab_init);
1141 module_exit(sunsab_exit);
1142
1143 MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1144 MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1145 MODULE_LICENSE("GPL");
Linux with added FPC-III support