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TTY: convert more flipping functions
[mirror_ubuntu-bionic-kernel.git] / drivers / tty / serial / sunsab.c
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_struct *
111 receive_chars(struct uart_sunsab_port *up,
112 union sab82532_irq_status *stat)
113 {
114 struct tty_struct *tty = 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 tty = up->port.state->port.tty;
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 tty;
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 if (tty == NULL) {
164 uart_handle_sysrq_char(&up->port, ch);
165 continue;
166 }
167
168 flag = TTY_NORMAL;
169 up->port.icount.rx++;
170
171 if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
172 SAB82532_ISR0_FERR |
173 SAB82532_ISR0_RFO)) ||
174 unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
175 /*
176 * For statistics only
177 */
178 if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
179 stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
180 SAB82532_ISR0_FERR);
181 up->port.icount.brk++;
182 /*
183 * We do the SysRQ and SAK checking
184 * here because otherwise the break
185 * may get masked by ignore_status_mask
186 * or read_status_mask.
187 */
188 if (uart_handle_break(&up->port))
189 continue;
190 } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
191 up->port.icount.parity++;
192 else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
193 up->port.icount.frame++;
194 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
195 up->port.icount.overrun++;
196
197 /*
198 * Mask off conditions which should be ingored.
199 */
200 stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
201 stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
202
203 if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
204 flag = TTY_BREAK;
205 } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
206 flag = TTY_PARITY;
207 else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
208 flag = TTY_FRAME;
209 }
210
211 if (uart_handle_sysrq_char(&up->port, ch))
212 continue;
213
214 if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
215 (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
216 tty_insert_flip_char(tty, ch, flag);
217 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
218 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
219 }
220
221 if (saw_console_brk)
222 sun_do_break();
223
224 return tty;
225 }
226
227 static void sunsab_stop_tx(struct uart_port *);
228 static void sunsab_tx_idle(struct uart_sunsab_port *);
229
230 static void transmit_chars(struct uart_sunsab_port *up,
231 union sab82532_irq_status *stat)
232 {
233 struct circ_buf *xmit = &up->port.state->xmit;
234 int i;
235
236 if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
237 up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
238 writeb(up->interrupt_mask1, &up->regs->w.imr1);
239 set_bit(SAB82532_ALLS, &up->irqflags);
240 }
241
242 #if 0 /* bde@nwlink.com says this check causes problems */
243 if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
244 return;
245 #endif
246
247 if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
248 return;
249
250 set_bit(SAB82532_XPR, &up->irqflags);
251 sunsab_tx_idle(up);
252
253 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
254 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
255 writeb(up->interrupt_mask1, &up->regs->w.imr1);
256 return;
257 }
258
259 up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
260 writeb(up->interrupt_mask1, &up->regs->w.imr1);
261 clear_bit(SAB82532_ALLS, &up->irqflags);
262
263 /* Stuff 32 bytes into Transmit FIFO. */
264 clear_bit(SAB82532_XPR, &up->irqflags);
265 for (i = 0; i < up->port.fifosize; i++) {
266 writeb(xmit->buf[xmit->tail],
267 &up->regs->w.xfifo[i]);
268 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
269 up->port.icount.tx++;
270 if (uart_circ_empty(xmit))
271 break;
272 }
273
274 /* Issue a Transmit Frame command. */
275 sunsab_cec_wait(up);
276 writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
277
278 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
279 uart_write_wakeup(&up->port);
280
281 if (uart_circ_empty(xmit))
282 sunsab_stop_tx(&up->port);
283 }
284
285 static void check_status(struct uart_sunsab_port *up,
286 union sab82532_irq_status *stat)
287 {
288 if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
289 uart_handle_dcd_change(&up->port,
290 !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
291
292 if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
293 uart_handle_cts_change(&up->port,
294 (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
295
296 if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
297 up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
298 up->port.icount.dsr++;
299 }
300
301 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
302 }
303
304 static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
305 {
306 struct uart_sunsab_port *up = dev_id;
307 struct tty_struct *tty;
308 union sab82532_irq_status status;
309 unsigned long flags;
310 unsigned char gis;
311
312 spin_lock_irqsave(&up->port.lock, flags);
313
314 status.stat = 0;
315 gis = readb(&up->regs->r.gis) >> up->gis_shift;
316 if (gis & 1)
317 status.sreg.isr0 = readb(&up->regs->r.isr0);
318 if (gis & 2)
319 status.sreg.isr1 = readb(&up->regs->r.isr1);
320
321 tty = NULL;
322 if (status.stat) {
323 if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
324 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
325 (status.sreg.isr1 & SAB82532_ISR1_BRK))
326 tty = receive_chars(up, &status);
327 if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
328 (status.sreg.isr1 & SAB82532_ISR1_CSC))
329 check_status(up, &status);
330 if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
331 transmit_chars(up, &status);
332 }
333
334 spin_unlock_irqrestore(&up->port.lock, flags);
335
336 if (tty)
337 tty_flip_buffer_push(tty);
338
339 return IRQ_HANDLED;
340 }
341
342 /* port->lock is not held. */
343 static unsigned int sunsab_tx_empty(struct uart_port *port)
344 {
345 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
346 int ret;
347
348 /* Do not need a lock for a state test like this. */
349 if (test_bit(SAB82532_ALLS, &up->irqflags))
350 ret = TIOCSER_TEMT;
351 else
352 ret = 0;
353
354 return ret;
355 }
356
357 /* port->lock held by caller. */
358 static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
359 {
360 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
361
362 if (mctrl & TIOCM_RTS) {
363 up->cached_mode &= ~SAB82532_MODE_FRTS;
364 up->cached_mode |= SAB82532_MODE_RTS;
365 } else {
366 up->cached_mode |= (SAB82532_MODE_FRTS |
367 SAB82532_MODE_RTS);
368 }
369 if (mctrl & TIOCM_DTR) {
370 up->cached_pvr &= ~(up->pvr_dtr_bit);
371 } else {
372 up->cached_pvr |= up->pvr_dtr_bit;
373 }
374
375 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
376 if (test_bit(SAB82532_XPR, &up->irqflags))
377 sunsab_tx_idle(up);
378 }
379
380 /* port->lock is held by caller and interrupts are disabled. */
381 static unsigned int sunsab_get_mctrl(struct uart_port *port)
382 {
383 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
384 unsigned char val;
385 unsigned int result;
386
387 result = 0;
388
389 val = readb(&up->regs->r.pvr);
390 result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
391
392 val = readb(&up->regs->r.vstr);
393 result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
394
395 val = readb(&up->regs->r.star);
396 result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
397
398 return result;
399 }
400
401 /* port->lock held by caller. */
402 static void sunsab_stop_tx(struct uart_port *port)
403 {
404 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
405
406 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
407 writeb(up->interrupt_mask1, &up->regs->w.imr1);
408 }
409
410 /* port->lock held by caller. */
411 static void sunsab_tx_idle(struct uart_sunsab_port *up)
412 {
413 if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
414 u8 tmp;
415
416 clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
417 writeb(up->cached_mode, &up->regs->rw.mode);
418 writeb(up->cached_pvr, &up->regs->rw.pvr);
419 writeb(up->cached_dafo, &up->regs->w.dafo);
420
421 writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
422 tmp = readb(&up->regs->rw.ccr2);
423 tmp &= ~0xc0;
424 tmp |= (up->cached_ebrg >> 2) & 0xc0;
425 writeb(tmp, &up->regs->rw.ccr2);
426 }
427 }
428
429 /* port->lock held by caller. */
430 static void sunsab_start_tx(struct uart_port *port)
431 {
432 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
433 struct circ_buf *xmit = &up->port.state->xmit;
434 int i;
435
436 up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
437 writeb(up->interrupt_mask1, &up->regs->w.imr1);
438
439 if (!test_bit(SAB82532_XPR, &up->irqflags))
440 return;
441
442 clear_bit(SAB82532_ALLS, &up->irqflags);
443 clear_bit(SAB82532_XPR, &up->irqflags);
444
445 for (i = 0; i < up->port.fifosize; i++) {
446 writeb(xmit->buf[xmit->tail],
447 &up->regs->w.xfifo[i]);
448 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
449 up->port.icount.tx++;
450 if (uart_circ_empty(xmit))
451 break;
452 }
453
454 /* Issue a Transmit Frame command. */
455 sunsab_cec_wait(up);
456 writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
457 }
458
459 /* port->lock is not held. */
460 static void sunsab_send_xchar(struct uart_port *port, char ch)
461 {
462 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
463 unsigned long flags;
464
465 spin_lock_irqsave(&up->port.lock, flags);
466
467 sunsab_tec_wait(up);
468 writeb(ch, &up->regs->w.tic);
469
470 spin_unlock_irqrestore(&up->port.lock, flags);
471 }
472
473 /* port->lock held by caller. */
474 static void sunsab_stop_rx(struct uart_port *port)
475 {
476 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
477
478 up->interrupt_mask0 |= SAB82532_IMR0_TCD;
479 writeb(up->interrupt_mask1, &up->regs->w.imr0);
480 }
481
482 /* port->lock held by caller. */
483 static void sunsab_enable_ms(struct uart_port *port)
484 {
485 /* For now we always receive these interrupts. */
486 }
487
488 /* port->lock is not held. */
489 static void sunsab_break_ctl(struct uart_port *port, int break_state)
490 {
491 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
492 unsigned long flags;
493 unsigned char val;
494
495 spin_lock_irqsave(&up->port.lock, flags);
496
497 val = up->cached_dafo;
498 if (break_state)
499 val |= SAB82532_DAFO_XBRK;
500 else
501 val &= ~SAB82532_DAFO_XBRK;
502 up->cached_dafo = val;
503
504 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
505 if (test_bit(SAB82532_XPR, &up->irqflags))
506 sunsab_tx_idle(up);
507
508 spin_unlock_irqrestore(&up->port.lock, flags);
509 }
510
511 /* port->lock is not held. */
512 static int sunsab_startup(struct uart_port *port)
513 {
514 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
515 unsigned long flags;
516 unsigned char tmp;
517 int err = request_irq(up->port.irq, sunsab_interrupt,
518 IRQF_SHARED, "sab", up);
519 if (err)
520 return err;
521
522 spin_lock_irqsave(&up->port.lock, flags);
523
524 /*
525 * Wait for any commands or immediate characters
526 */
527 sunsab_cec_wait(up);
528 sunsab_tec_wait(up);
529
530 /*
531 * Clear the FIFO buffers.
532 */
533 writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
534 sunsab_cec_wait(up);
535 writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
536
537 /*
538 * Clear the interrupt registers.
539 */
540 (void) readb(&up->regs->r.isr0);
541 (void) readb(&up->regs->r.isr1);
542
543 /*
544 * Now, initialize the UART
545 */
546 writeb(0, &up->regs->w.ccr0); /* power-down */
547 writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
548 SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
549 writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
550 writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
551 SAB82532_CCR2_TOE, &up->regs->w.ccr2);
552 writeb(0, &up->regs->w.ccr3);
553 writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
554 up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
555 SAB82532_MODE_RAC);
556 writeb(up->cached_mode, &up->regs->w.mode);
557 writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
558
559 tmp = readb(&up->regs->rw.ccr0);
560 tmp |= SAB82532_CCR0_PU; /* power-up */
561 writeb(tmp, &up->regs->rw.ccr0);
562
563 /*
564 * Finally, enable interrupts
565 */
566 up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
567 SAB82532_IMR0_PLLA);
568 writeb(up->interrupt_mask0, &up->regs->w.imr0);
569 up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
570 SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
571 SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
572 SAB82532_IMR1_XPR);
573 writeb(up->interrupt_mask1, &up->regs->w.imr1);
574 set_bit(SAB82532_ALLS, &up->irqflags);
575 set_bit(SAB82532_XPR, &up->irqflags);
576
577 spin_unlock_irqrestore(&up->port.lock, flags);
578
579 return 0;
580 }
581
582 /* port->lock is not held. */
583 static void sunsab_shutdown(struct uart_port *port)
584 {
585 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
586 unsigned long flags;
587
588 spin_lock_irqsave(&up->port.lock, flags);
589
590 /* Disable Interrupts */
591 up->interrupt_mask0 = 0xff;
592 writeb(up->interrupt_mask0, &up->regs->w.imr0);
593 up->interrupt_mask1 = 0xff;
594 writeb(up->interrupt_mask1, &up->regs->w.imr1);
595
596 /* Disable break condition */
597 up->cached_dafo = readb(&up->regs->rw.dafo);
598 up->cached_dafo &= ~SAB82532_DAFO_XBRK;
599 writeb(up->cached_dafo, &up->regs->rw.dafo);
600
601 /* Disable Receiver */
602 up->cached_mode &= ~SAB82532_MODE_RAC;
603 writeb(up->cached_mode, &up->regs->rw.mode);
604
605 /*
606 * XXX FIXME
607 *
608 * If the chip is powered down here the system hangs/crashes during
609 * reboot or shutdown. This needs to be investigated further,
610 * similar behaviour occurs in 2.4 when the driver is configured
611 * as a module only. One hint may be that data is sometimes
612 * transmitted at 9600 baud during shutdown (regardless of the
613 * speed the chip was configured for when the port was open).
614 */
615 #if 0
616 /* Power Down */
617 tmp = readb(&up->regs->rw.ccr0);
618 tmp &= ~SAB82532_CCR0_PU;
619 writeb(tmp, &up->regs->rw.ccr0);
620 #endif
621
622 spin_unlock_irqrestore(&up->port.lock, flags);
623 free_irq(up->port.irq, up);
624 }
625
626 /*
627 * This is used to figure out the divisor speeds.
628 *
629 * The formula is: Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
630 *
631 * with 0 <= N < 64 and 0 <= M < 16
632 */
633
634 static void calc_ebrg(int baud, int *n_ret, int *m_ret)
635 {
636 int n, m;
637
638 if (baud == 0) {
639 *n_ret = 0;
640 *m_ret = 0;
641 return;
642 }
643
644 /*
645 * We scale numbers by 10 so that we get better accuracy
646 * without having to use floating point. Here we increment m
647 * until n is within the valid range.
648 */
649 n = (SAB_BASE_BAUD * 10) / baud;
650 m = 0;
651 while (n >= 640) {
652 n = n / 2;
653 m++;
654 }
655 n = (n+5) / 10;
656 /*
657 * We try very hard to avoid speeds with M == 0 since they may
658 * not work correctly for XTAL frequences above 10 MHz.
659 */
660 if ((m == 0) && ((n & 1) == 0)) {
661 n = n / 2;
662 m++;
663 }
664 *n_ret = n - 1;
665 *m_ret = m;
666 }
667
668 /* Internal routine, port->lock is held and local interrupts are disabled. */
669 static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
670 unsigned int iflag, unsigned int baud,
671 unsigned int quot)
672 {
673 unsigned char dafo;
674 int bits, n, m;
675
676 /* Byte size and parity */
677 switch (cflag & CSIZE) {
678 case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
679 case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
680 case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
681 case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
682 /* Never happens, but GCC is too dumb to figure it out */
683 default: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
684 }
685
686 if (cflag & CSTOPB) {
687 dafo |= SAB82532_DAFO_STOP;
688 bits++;
689 }
690
691 if (cflag & PARENB) {
692 dafo |= SAB82532_DAFO_PARE;
693 bits++;
694 }
695
696 if (cflag & PARODD) {
697 dafo |= SAB82532_DAFO_PAR_ODD;
698 } else {
699 dafo |= SAB82532_DAFO_PAR_EVEN;
700 }
701 up->cached_dafo = dafo;
702
703 calc_ebrg(baud, &n, &m);
704
705 up->cached_ebrg = n | (m << 6);
706
707 up->tec_timeout = (10 * 1000000) / baud;
708 up->cec_timeout = up->tec_timeout >> 2;
709
710 /* CTS flow control flags */
711 /* We encode read_status_mask and ignore_status_mask like so:
712 *
713 * ---------------------
714 * | ... | ISR1 | ISR0 |
715 * ---------------------
716 * .. 15 8 7 0
717 */
718
719 up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
720 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
721 SAB82532_ISR0_CDSC);
722 up->port.read_status_mask |= (SAB82532_ISR1_CSC |
723 SAB82532_ISR1_ALLS |
724 SAB82532_ISR1_XPR) << 8;
725 if (iflag & INPCK)
726 up->port.read_status_mask |= (SAB82532_ISR0_PERR |
727 SAB82532_ISR0_FERR);
728 if (iflag & (BRKINT | PARMRK))
729 up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
730
731 /*
732 * Characteres to ignore
733 */
734 up->port.ignore_status_mask = 0;
735 if (iflag & IGNPAR)
736 up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
737 SAB82532_ISR0_FERR);
738 if (iflag & IGNBRK) {
739 up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
740 /*
741 * If we're ignoring parity and break indicators,
742 * ignore overruns too (for real raw support).
743 */
744 if (iflag & IGNPAR)
745 up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
746 }
747
748 /*
749 * ignore all characters if CREAD is not set
750 */
751 if ((cflag & CREAD) == 0)
752 up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
753 SAB82532_ISR0_TCD);
754
755 uart_update_timeout(&up->port, cflag,
756 (up->port.uartclk / (16 * quot)));
757
758 /* Now schedule a register update when the chip's
759 * transmitter is idle.
760 */
761 up->cached_mode |= SAB82532_MODE_RAC;
762 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
763 if (test_bit(SAB82532_XPR, &up->irqflags))
764 sunsab_tx_idle(up);
765 }
766
767 /* port->lock is not held. */
768 static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
769 struct ktermios *old)
770 {
771 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
772 unsigned long flags;
773 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
774 unsigned int quot = uart_get_divisor(port, baud);
775
776 spin_lock_irqsave(&up->port.lock, flags);
777 sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
778 spin_unlock_irqrestore(&up->port.lock, flags);
779 }
780
781 static const char *sunsab_type(struct uart_port *port)
782 {
783 struct uart_sunsab_port *up = (void *)port;
784 static char buf[36];
785
786 sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
787 return buf;
788 }
789
790 static void sunsab_release_port(struct uart_port *port)
791 {
792 }
793
794 static int sunsab_request_port(struct uart_port *port)
795 {
796 return 0;
797 }
798
799 static void sunsab_config_port(struct uart_port *port, int flags)
800 {
801 }
802
803 static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
804 {
805 return -EINVAL;
806 }
807
808 static struct uart_ops sunsab_pops = {
809 .tx_empty = sunsab_tx_empty,
810 .set_mctrl = sunsab_set_mctrl,
811 .get_mctrl = sunsab_get_mctrl,
812 .stop_tx = sunsab_stop_tx,
813 .start_tx = sunsab_start_tx,
814 .send_xchar = sunsab_send_xchar,
815 .stop_rx = sunsab_stop_rx,
816 .enable_ms = sunsab_enable_ms,
817 .break_ctl = sunsab_break_ctl,
818 .startup = sunsab_startup,
819 .shutdown = sunsab_shutdown,
820 .set_termios = sunsab_set_termios,
821 .type = sunsab_type,
822 .release_port = sunsab_release_port,
823 .request_port = sunsab_request_port,
824 .config_port = sunsab_config_port,
825 .verify_port = sunsab_verify_port,
826 };
827
828 static struct uart_driver sunsab_reg = {
829 .owner = THIS_MODULE,
830 .driver_name = "sunsab",
831 .dev_name = "ttyS",
832 .major = TTY_MAJOR,
833 };
834
835 static struct uart_sunsab_port *sunsab_ports;
836
837 #ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
838
839 static void sunsab_console_putchar(struct uart_port *port, int c)
840 {
841 struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
842
843 sunsab_tec_wait(up);
844 writeb(c, &up->regs->w.tic);
845 }
846
847 static void sunsab_console_write(struct console *con, const char *s, unsigned n)
848 {
849 struct uart_sunsab_port *up = &sunsab_ports[con->index];
850 unsigned long flags;
851 int locked = 1;
852
853 local_irq_save(flags);
854 if (up->port.sysrq) {
855 locked = 0;
856 } else if (oops_in_progress) {
857 locked = spin_trylock(&up->port.lock);
858 } else
859 spin_lock(&up->port.lock);
860
861 uart_console_write(&up->port, s, n, sunsab_console_putchar);
862 sunsab_tec_wait(up);
863
864 if (locked)
865 spin_unlock(&up->port.lock);
866 local_irq_restore(flags);
867 }
868
869 static int sunsab_console_setup(struct console *con, char *options)
870 {
871 struct uart_sunsab_port *up = &sunsab_ports[con->index];
872 unsigned long flags;
873 unsigned int baud, quot;
874
875 /*
876 * The console framework calls us for each and every port
877 * registered. Defer the console setup until the requested
878 * port has been properly discovered. A bit of a hack,
879 * though...
880 */
881 if (up->port.type != PORT_SUNSAB)
882 return -1;
883
884 printk("Console: ttyS%d (SAB82532)\n",
885 (sunsab_reg.minor - 64) + con->index);
886
887 sunserial_console_termios(con, up->port.dev->of_node);
888
889 switch (con->cflag & CBAUD) {
890 case B150: baud = 150; break;
891 case B300: baud = 300; break;
892 case B600: baud = 600; break;
893 case B1200: baud = 1200; break;
894 case B2400: baud = 2400; break;
895 case B4800: baud = 4800; break;
896 default: case B9600: baud = 9600; break;
897 case B19200: baud = 19200; break;
898 case B38400: baud = 38400; break;
899 case B57600: baud = 57600; break;
900 case B115200: baud = 115200; break;
901 case B230400: baud = 230400; break;
902 case B460800: baud = 460800; break;
903 };
904
905 /*
906 * Temporary fix.
907 */
908 spin_lock_init(&up->port.lock);
909
910 /*
911 * Initialize the hardware
912 */
913 sunsab_startup(&up->port);
914
915 spin_lock_irqsave(&up->port.lock, flags);
916
917 /*
918 * Finally, enable interrupts
919 */
920 up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
921 SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
922 writeb(up->interrupt_mask0, &up->regs->w.imr0);
923 up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
924 SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
925 SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
926 SAB82532_IMR1_XPR;
927 writeb(up->interrupt_mask1, &up->regs->w.imr1);
928
929 quot = uart_get_divisor(&up->port, baud);
930 sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
931 sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
932
933 spin_unlock_irqrestore(&up->port.lock, flags);
934
935 return 0;
936 }
937
938 static struct console sunsab_console = {
939 .name = "ttyS",
940 .write = sunsab_console_write,
941 .device = uart_console_device,
942 .setup = sunsab_console_setup,
943 .flags = CON_PRINTBUFFER,
944 .index = -1,
945 .data = &sunsab_reg,
946 };
947
948 static inline struct console *SUNSAB_CONSOLE(void)
949 {
950 return &sunsab_console;
951 }
952 #else
953 #define SUNSAB_CONSOLE() (NULL)
954 #define sunsab_console_init() do { } while (0)
955 #endif
956
957 static int sunsab_init_one(struct uart_sunsab_port *up,
958 struct platform_device *op,
959 unsigned long offset,
960 int line)
961 {
962 up->port.line = line;
963 up->port.dev = &op->dev;
964
965 up->port.mapbase = op->resource[0].start + offset;
966 up->port.membase = of_ioremap(&op->resource[0], offset,
967 sizeof(union sab82532_async_regs),
968 "sab");
969 if (!up->port.membase)
970 return -ENOMEM;
971 up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
972
973 up->port.irq = op->archdata.irqs[0];
974
975 up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
976 up->port.iotype = UPIO_MEM;
977
978 writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
979
980 up->port.ops = &sunsab_pops;
981 up->port.type = PORT_SUNSAB;
982 up->port.uartclk = SAB_BASE_BAUD;
983
984 up->type = readb(&up->regs->r.vstr) & 0x0f;
985 writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
986 writeb(0xff, &up->regs->w.pim);
987 if ((up->port.line & 0x1) == 0) {
988 up->pvr_dsr_bit = (1 << 0);
989 up->pvr_dtr_bit = (1 << 1);
990 up->gis_shift = 2;
991 } else {
992 up->pvr_dsr_bit = (1 << 3);
993 up->pvr_dtr_bit = (1 << 2);
994 up->gis_shift = 0;
995 }
996 up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
997 writeb(up->cached_pvr, &up->regs->w.pvr);
998 up->cached_mode = readb(&up->regs->rw.mode);
999 up->cached_mode |= SAB82532_MODE_FRTS;
1000 writeb(up->cached_mode, &up->regs->rw.mode);
1001 up->cached_mode |= SAB82532_MODE_RTS;
1002 writeb(up->cached_mode, &up->regs->rw.mode);
1003
1004 up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1005 up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1006
1007 return 0;
1008 }
1009
1010 static int sab_probe(struct platform_device *op)
1011 {
1012 static int inst;
1013 struct uart_sunsab_port *up;
1014 int err;
1015
1016 up = &sunsab_ports[inst * 2];
1017
1018 err = sunsab_init_one(&up[0], op,
1019 0,
1020 (inst * 2) + 0);
1021 if (err)
1022 goto out;
1023
1024 err = sunsab_init_one(&up[1], op,
1025 sizeof(union sab82532_async_regs),
1026 (inst * 2) + 1);
1027 if (err)
1028 goto out1;
1029
1030 sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1031 &sunsab_reg, up[0].port.line,
1032 false);
1033
1034 sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1035 &sunsab_reg, up[1].port.line,
1036 false);
1037
1038 err = uart_add_one_port(&sunsab_reg, &up[0].port);
1039 if (err)
1040 goto out2;
1041
1042 err = uart_add_one_port(&sunsab_reg, &up[1].port);
1043 if (err)
1044 goto out3;
1045
1046 dev_set_drvdata(&op->dev, &up[0]);
1047
1048 inst++;
1049
1050 return 0;
1051
1052 out3:
1053 uart_remove_one_port(&sunsab_reg, &up[0].port);
1054 out2:
1055 of_iounmap(&op->resource[0],
1056 up[1].port.membase,
1057 sizeof(union sab82532_async_regs));
1058 out1:
1059 of_iounmap(&op->resource[0],
1060 up[0].port.membase,
1061 sizeof(union sab82532_async_regs));
1062 out:
1063 return err;
1064 }
1065
1066 static int sab_remove(struct platform_device *op)
1067 {
1068 struct uart_sunsab_port *up = dev_get_drvdata(&op->dev);
1069
1070 uart_remove_one_port(&sunsab_reg, &up[1].port);
1071 uart_remove_one_port(&sunsab_reg, &up[0].port);
1072 of_iounmap(&op->resource[0],
1073 up[1].port.membase,
1074 sizeof(union sab82532_async_regs));
1075 of_iounmap(&op->resource[0],
1076 up[0].port.membase,
1077 sizeof(union sab82532_async_regs));
1078
1079 dev_set_drvdata(&op->dev, NULL);
1080
1081 return 0;
1082 }
1083
1084 static const struct of_device_id sab_match[] = {
1085 {
1086 .name = "se",
1087 },
1088 {
1089 .name = "serial",
1090 .compatible = "sab82532",
1091 },
1092 {},
1093 };
1094 MODULE_DEVICE_TABLE(of, sab_match);
1095
1096 static struct platform_driver sab_driver = {
1097 .driver = {
1098 .name = "sab",
1099 .owner = THIS_MODULE,
1100 .of_match_table = sab_match,
1101 },
1102 .probe = sab_probe,
1103 .remove = sab_remove,
1104 };
1105
1106 static int __init sunsab_init(void)
1107 {
1108 struct device_node *dp;
1109 int err;
1110 int num_channels = 0;
1111
1112 for_each_node_by_name(dp, "se")
1113 num_channels += 2;
1114 for_each_node_by_name(dp, "serial") {
1115 if (of_device_is_compatible(dp, "sab82532"))
1116 num_channels += 2;
1117 }
1118
1119 if (num_channels) {
1120 sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1121 num_channels, GFP_KERNEL);
1122 if (!sunsab_ports)
1123 return -ENOMEM;
1124
1125 err = sunserial_register_minors(&sunsab_reg, num_channels);
1126 if (err) {
1127 kfree(sunsab_ports);
1128 sunsab_ports = NULL;
1129
1130 return err;
1131 }
1132 }
1133
1134 return platform_driver_register(&sab_driver);
1135 }
1136
1137 static void __exit sunsab_exit(void)
1138 {
1139 platform_driver_unregister(&sab_driver);
1140 if (sunsab_reg.nr) {
1141 sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1142 }
1143
1144 kfree(sunsab_ports);
1145 sunsab_ports = NULL;
1146 }
1147
1148 module_init(sunsab_init);
1149 module_exit(sunsab_exit);
1150
1151 MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1152 MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1153 MODULE_LICENSE("GPL");
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