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1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 *
4 * Copyright (C) 2008 Christian Pellegrin <chripell@evolware.org>
5 *
6 * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have
7 * to use polling for flow control. TX empty IRQ is unusable, since
8 * writing conf clears FIFO buffer and we cannot have this interrupt
9 * always asking us for attention.
10 *
11 * Example platform data:
12
13 static struct plat_max3100 max3100_plat_data = {
14 .loopback = 0,
15 .crystal = 0,
16 .poll_time = 100,
17 };
18
19 static struct spi_board_info spi_board_info[] = {
20 {
21 .modalias = "max3100",
22 .platform_data = &max3100_plat_data,
23 .irq = IRQ_EINT12,
24 .max_speed_hz = 5*1000*1000,
25 .chip_select = 0,
26 },
27 };
28
29 * The initial minor number is 209 in the low-density serial port:
30 * mknod /dev/ttyMAX0 c 204 209
31 */
32
33 #define MAX3100_MAJOR 204
34 #define MAX3100_MINOR 209
35 /* 4 MAX3100s should be enough for everyone */
36 #define MAX_MAX3100 4
37
38 #include <linux/delay.h>
39 #include <linux/slab.h>
40 #include <linux/device.h>
41 #include <linux/module.h>
42 #include <linux/serial_core.h>
43 #include <linux/serial.h>
44 #include <linux/spi/spi.h>
45 #include <linux/freezer.h>
46 #include <linux/tty.h>
47 #include <linux/tty_flip.h>
48
49 #include <linux/serial_max3100.h>
50
51 #define MAX3100_C (1<<14)
52 #define MAX3100_D (0<<14)
53 #define MAX3100_W (1<<15)
54 #define MAX3100_RX (0<<15)
55
56 #define MAX3100_WC (MAX3100_W | MAX3100_C)
57 #define MAX3100_RC (MAX3100_RX | MAX3100_C)
58 #define MAX3100_WD (MAX3100_W | MAX3100_D)
59 #define MAX3100_RD (MAX3100_RX | MAX3100_D)
60 #define MAX3100_CMD (3 << 14)
61
62 #define MAX3100_T (1<<14)
63 #define MAX3100_R (1<<15)
64
65 #define MAX3100_FEN (1<<13)
66 #define MAX3100_SHDN (1<<12)
67 #define MAX3100_TM (1<<11)
68 #define MAX3100_RM (1<<10)
69 #define MAX3100_PM (1<<9)
70 #define MAX3100_RAM (1<<8)
71 #define MAX3100_IR (1<<7)
72 #define MAX3100_ST (1<<6)
73 #define MAX3100_PE (1<<5)
74 #define MAX3100_L (1<<4)
75 #define MAX3100_BAUD (0xf)
76
77 #define MAX3100_TE (1<<10)
78 #define MAX3100_RAFE (1<<10)
79 #define MAX3100_RTS (1<<9)
80 #define MAX3100_CTS (1<<9)
81 #define MAX3100_PT (1<<8)
82 #define MAX3100_DATA (0xff)
83
84 #define MAX3100_RT (MAX3100_R | MAX3100_T)
85 #define MAX3100_RTC (MAX3100_RT | MAX3100_CTS | MAX3100_RAFE)
86
87 /* the following simulate a status reg for ignore_status_mask */
88 #define MAX3100_STATUS_PE 1
89 #define MAX3100_STATUS_FE 2
90 #define MAX3100_STATUS_OE 4
91
92 struct max3100_port {
93 struct uart_port port;
94 struct spi_device *spi;
95
96 int cts; /* last CTS received for flow ctrl */
97 int tx_empty; /* last TX empty bit */
98
99 spinlock_t conf_lock; /* shared data */
100 int conf_commit; /* need to make changes */
101 int conf; /* configuration for the MAX31000
102 * (bits 0-7, bits 8-11 are irqs) */
103 int rts_commit; /* need to change rts */
104 int rts; /* rts status */
105 int baud; /* current baud rate */
106
107 int parity; /* keeps track if we should send parity */
108 #define MAX3100_PARITY_ON 1
109 #define MAX3100_PARITY_ODD 2
110 #define MAX3100_7BIT 4
111 int rx_enabled; /* if we should rx chars */
112
113 int irq; /* irq assigned to the max3100 */
114
115 int minor; /* minor number */
116 int crystal; /* 1 if 3.6864Mhz crystal 0 for 1.8432 */
117 int loopback; /* 1 if we are in loopback mode */
118
119 /* for handling irqs: need workqueue since we do spi_sync */
120 struct workqueue_struct *workqueue;
121 struct work_struct work;
122 /* set to 1 to make the workhandler exit as soon as possible */
123 int force_end_work;
124 /* need to know we are suspending to avoid deadlock on workqueue */
125 int suspending;
126
127 /* hook for suspending MAX3100 via dedicated pin */
128 void (*max3100_hw_suspend) (int suspend);
129
130 /* poll time (in ms) for ctrl lines */
131 int poll_time;
132 /* and its timer */
133 struct timer_list timer;
134 };
135
136 static struct max3100_port *max3100s[MAX_MAX3100]; /* the chips */
137 static DEFINE_MUTEX(max3100s_lock); /* race on probe */
138
139 static int max3100_do_parity(struct max3100_port *s, u16 c)
140 {
141 int parity;
142
143 if (s->parity & MAX3100_PARITY_ODD)
144 parity = 1;
145 else
146 parity = 0;
147
148 if (s->parity & MAX3100_7BIT)
149 c &= 0x7f;
150 else
151 c &= 0xff;
152
153 parity = parity ^ (hweight8(c) & 1);
154 return parity;
155 }
156
157 static int max3100_check_parity(struct max3100_port *s, u16 c)
158 {
159 return max3100_do_parity(s, c) == ((c >> 8) & 1);
160 }
161
162 static void max3100_calc_parity(struct max3100_port *s, u16 *c)
163 {
164 if (s->parity & MAX3100_7BIT)
165 *c &= 0x7f;
166 else
167 *c &= 0xff;
168
169 if (s->parity & MAX3100_PARITY_ON)
170 *c |= max3100_do_parity(s, *c) << 8;
171 }
172
173 static void max3100_work(struct work_struct *w);
174
175 static void max3100_dowork(struct max3100_port *s)
176 {
177 if (!s->force_end_work && !freezing(current) && !s->suspending)
178 queue_work(s->workqueue, &s->work);
179 }
180
181 static void max3100_timeout(struct timer_list *t)
182 {
183 struct max3100_port *s = from_timer(s, t, timer);
184
185 if (s->port.state) {
186 max3100_dowork(s);
187 mod_timer(&s->timer, jiffies + s->poll_time);
188 }
189 }
190
191 static int max3100_sr(struct max3100_port *s, u16 tx, u16 *rx)
192 {
193 struct spi_message message;
194 u16 etx, erx;
195 int status;
196 struct spi_transfer tran = {
197 .tx_buf = &etx,
198 .rx_buf = &erx,
199 .len = 2,
200 };
201
202 etx = cpu_to_be16(tx);
203 spi_message_init(&message);
204 spi_message_add_tail(&tran, &message);
205 status = spi_sync(s->spi, &message);
206 if (status) {
207 dev_warn(&s->spi->dev, "error while calling spi_sync\n");
208 return -EIO;
209 }
210 *rx = be16_to_cpu(erx);
211 s->tx_empty = (*rx & MAX3100_T) > 0;
212 dev_dbg(&s->spi->dev, "%04x - %04x\n", tx, *rx);
213 return 0;
214 }
215
216 static int max3100_handlerx_unlocked(struct max3100_port *s, u16 rx)
217 {
218 unsigned int status = 0;
219 int ret = 0, cts;
220 u8 ch, flg;
221
222 if (rx & MAX3100_R && s->rx_enabled) {
223 dev_dbg(&s->spi->dev, "%s\n", __func__);
224 ch = rx & (s->parity & MAX3100_7BIT ? 0x7f : 0xff);
225 if (rx & MAX3100_RAFE) {
226 s->port.icount.frame++;
227 flg = TTY_FRAME;
228 status |= MAX3100_STATUS_FE;
229 } else {
230 if (s->parity & MAX3100_PARITY_ON) {
231 if (max3100_check_parity(s, rx)) {
232 s->port.icount.rx++;
233 flg = TTY_NORMAL;
234 } else {
235 s->port.icount.parity++;
236 flg = TTY_PARITY;
237 status |= MAX3100_STATUS_PE;
238 }
239 } else {
240 s->port.icount.rx++;
241 flg = TTY_NORMAL;
242 }
243 }
244 uart_insert_char(&s->port, status, MAX3100_STATUS_OE, ch, flg);
245 ret = 1;
246 }
247
248 cts = (rx & MAX3100_CTS) > 0;
249 if (s->cts != cts) {
250 s->cts = cts;
251 uart_handle_cts_change(&s->port, cts);
252 }
253
254 return ret;
255 }
256
257 static int max3100_handlerx(struct max3100_port *s, u16 rx)
258 {
259 unsigned long flags;
260 int ret;
261
262 uart_port_lock_irqsave(&s->port, &flags);
263 ret = max3100_handlerx_unlocked(s, rx);
264 uart_port_unlock_irqrestore(&s->port, flags);
265 return ret;
266 }
267
268 static void max3100_work(struct work_struct *w)
269 {
270 struct max3100_port *s = container_of(w, struct max3100_port, work);
271 struct tty_port *tport = &s->port.state->port;
272 unsigned char ch;
273 int rxchars;
274 u16 tx, rx;
275 int conf, cconf, crts;
276
277 dev_dbg(&s->spi->dev, "%s\n", __func__);
278
279 rxchars = 0;
280 do {
281 spin_lock(&s->conf_lock);
282 conf = s->conf;
283 cconf = s->conf_commit;
284 s->conf_commit = 0;
285 crts = s->rts_commit;
286 s->rts_commit = 0;
287 spin_unlock(&s->conf_lock);
288 if (cconf)
289 max3100_sr(s, MAX3100_WC | conf, &rx);
290 if (crts) {
291 max3100_sr(s, MAX3100_WD | MAX3100_TE |
292 (s->rts ? MAX3100_RTS : 0), &rx);
293 rxchars += max3100_handlerx(s, rx);
294 }
295
296 max3100_sr(s, MAX3100_RD, &rx);
297 rxchars += max3100_handlerx(s, rx);
298
299 if (rx & MAX3100_T) {
300 tx = 0xffff;
301 if (s->port.x_char) {
302 tx = s->port.x_char;
303 s->port.icount.tx++;
304 s->port.x_char = 0;
305 } else if (!uart_tx_stopped(&s->port) &&
306 uart_fifo_get(&s->port, &ch)) {
307 tx = ch;
308 }
309 if (tx != 0xffff) {
310 max3100_calc_parity(s, &tx);
311 tx |= MAX3100_WD | (s->rts ? MAX3100_RTS : 0);
312 max3100_sr(s, tx, &rx);
313 rxchars += max3100_handlerx(s, rx);
314 }
315 }
316
317 if (rxchars > 16) {
318 tty_flip_buffer_push(&s->port.state->port);
319 rxchars = 0;
320 }
321 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
322 uart_write_wakeup(&s->port);
323
324 } while (!s->force_end_work &&
325 !freezing(current) &&
326 ((rx & MAX3100_R) ||
327 (!kfifo_is_empty(&tport->xmit_fifo) &&
328 !uart_tx_stopped(&s->port))));
329
330 if (rxchars > 0)
331 tty_flip_buffer_push(&s->port.state->port);
332 }
333
334 static irqreturn_t max3100_irq(int irqno, void *dev_id)
335 {
336 struct max3100_port *s = dev_id;
337
338 dev_dbg(&s->spi->dev, "%s\n", __func__);
339
340 max3100_dowork(s);
341 return IRQ_HANDLED;
342 }
343
344 static void max3100_enable_ms(struct uart_port *port)
345 {
346 struct max3100_port *s = container_of(port,
347 struct max3100_port,
348 port);
349
350 if (s->poll_time > 0)
351 mod_timer(&s->timer, jiffies);
352 dev_dbg(&s->spi->dev, "%s\n", __func__);
353 }
354
355 static void max3100_start_tx(struct uart_port *port)
356 {
357 struct max3100_port *s = container_of(port,
358 struct max3100_port,
359 port);
360
361 dev_dbg(&s->spi->dev, "%s\n", __func__);
362
363 max3100_dowork(s);
364 }
365
366 static void max3100_stop_rx(struct uart_port *port)
367 {
368 struct max3100_port *s = container_of(port,
369 struct max3100_port,
370 port);
371
372 dev_dbg(&s->spi->dev, "%s\n", __func__);
373
374 s->rx_enabled = 0;
375 spin_lock(&s->conf_lock);
376 s->conf &= ~MAX3100_RM;
377 s->conf_commit = 1;
378 spin_unlock(&s->conf_lock);
379 max3100_dowork(s);
380 }
381
382 static unsigned int max3100_tx_empty(struct uart_port *port)
383 {
384 struct max3100_port *s = container_of(port,
385 struct max3100_port,
386 port);
387
388 dev_dbg(&s->spi->dev, "%s\n", __func__);
389
390 /* may not be truly up-to-date */
391 max3100_dowork(s);
392 return s->tx_empty;
393 }
394
395 static unsigned int max3100_get_mctrl(struct uart_port *port)
396 {
397 struct max3100_port *s = container_of(port,
398 struct max3100_port,
399 port);
400
401 dev_dbg(&s->spi->dev, "%s\n", __func__);
402
403 /* may not be truly up-to-date */
404 max3100_dowork(s);
405 /* always assert DCD and DSR since these lines are not wired */
406 return (s->cts ? TIOCM_CTS : 0) | TIOCM_DSR | TIOCM_CAR;
407 }
408
409 static void max3100_set_mctrl(struct uart_port *port, unsigned int mctrl)
410 {
411 struct max3100_port *s = container_of(port,
412 struct max3100_port,
413 port);
414 int rts;
415
416 dev_dbg(&s->spi->dev, "%s\n", __func__);
417
418 rts = (mctrl & TIOCM_RTS) > 0;
419
420 spin_lock(&s->conf_lock);
421 if (s->rts != rts) {
422 s->rts = rts;
423 s->rts_commit = 1;
424 max3100_dowork(s);
425 }
426 spin_unlock(&s->conf_lock);
427 }
428
429 static void
430 max3100_set_termios(struct uart_port *port, struct ktermios *termios,
431 const struct ktermios *old)
432 {
433 struct max3100_port *s = container_of(port,
434 struct max3100_port,
435 port);
436 int baud = 0;
437 unsigned cflag;
438 u32 param_new, param_mask, parity = 0;
439
440 dev_dbg(&s->spi->dev, "%s\n", __func__);
441
442 cflag = termios->c_cflag;
443 param_mask = 0;
444
445 baud = tty_termios_baud_rate(termios);
446 param_new = s->conf & MAX3100_BAUD;
447 switch (baud) {
448 case 300:
449 if (s->crystal)
450 baud = s->baud;
451 else
452 param_new = 15;
453 break;
454 case 600:
455 param_new = 14 + s->crystal;
456 break;
457 case 1200:
458 param_new = 13 + s->crystal;
459 break;
460 case 2400:
461 param_new = 12 + s->crystal;
462 break;
463 case 4800:
464 param_new = 11 + s->crystal;
465 break;
466 case 9600:
467 param_new = 10 + s->crystal;
468 break;
469 case 19200:
470 param_new = 9 + s->crystal;
471 break;
472 case 38400:
473 param_new = 8 + s->crystal;
474 break;
475 case 57600:
476 param_new = 1 + s->crystal;
477 break;
478 case 115200:
479 param_new = 0 + s->crystal;
480 break;
481 case 230400:
482 if (s->crystal)
483 param_new = 0;
484 else
485 baud = s->baud;
486 break;
487 default:
488 baud = s->baud;
489 }
490 tty_termios_encode_baud_rate(termios, baud, baud);
491 s->baud = baud;
492 param_mask |= MAX3100_BAUD;
493
494 if ((cflag & CSIZE) == CS8) {
495 param_new &= ~MAX3100_L;
496 parity &= ~MAX3100_7BIT;
497 } else {
498 param_new |= MAX3100_L;
499 parity |= MAX3100_7BIT;
500 cflag = (cflag & ~CSIZE) | CS7;
501 }
502 param_mask |= MAX3100_L;
503
504 if (cflag & CSTOPB)
505 param_new |= MAX3100_ST;
506 else
507 param_new &= ~MAX3100_ST;
508 param_mask |= MAX3100_ST;
509
510 if (cflag & PARENB) {
511 param_new |= MAX3100_PE;
512 parity |= MAX3100_PARITY_ON;
513 } else {
514 param_new &= ~MAX3100_PE;
515 parity &= ~MAX3100_PARITY_ON;
516 }
517 param_mask |= MAX3100_PE;
518
519 if (cflag & PARODD)
520 parity |= MAX3100_PARITY_ODD;
521 else
522 parity &= ~MAX3100_PARITY_ODD;
523
524 /* mask termios capabilities we don't support */
525 cflag &= ~CMSPAR;
526 termios->c_cflag = cflag;
527
528 s->port.ignore_status_mask = 0;
529 if (termios->c_iflag & IGNPAR)
530 s->port.ignore_status_mask |=
531 MAX3100_STATUS_PE | MAX3100_STATUS_FE |
532 MAX3100_STATUS_OE;
533
534 if (s->poll_time > 0)
535 del_timer_sync(&s->timer);
536
537 uart_update_timeout(port, termios->c_cflag, baud);
538
539 spin_lock(&s->conf_lock);
540 s->conf = (s->conf & ~param_mask) | (param_new & param_mask);
541 s->conf_commit = 1;
542 s->parity = parity;
543 spin_unlock(&s->conf_lock);
544 max3100_dowork(s);
545
546 if (UART_ENABLE_MS(&s->port, termios->c_cflag))
547 max3100_enable_ms(&s->port);
548 }
549
550 static void max3100_shutdown(struct uart_port *port)
551 {
552 struct max3100_port *s = container_of(port,
553 struct max3100_port,
554 port);
555
556 dev_dbg(&s->spi->dev, "%s\n", __func__);
557
558 if (s->suspending)
559 return;
560
561 s->force_end_work = 1;
562
563 if (s->poll_time > 0)
564 del_timer_sync(&s->timer);
565
566 if (s->workqueue) {
567 destroy_workqueue(s->workqueue);
568 s->workqueue = NULL;
569 }
570 if (s->irq)
571 free_irq(s->irq, s);
572
573 /* set shutdown mode to save power */
574 if (s->max3100_hw_suspend)
575 s->max3100_hw_suspend(1);
576 else {
577 u16 tx, rx;
578
579 tx = MAX3100_WC | MAX3100_SHDN;
580 max3100_sr(s, tx, &rx);
581 }
582 }
583
584 static int max3100_startup(struct uart_port *port)
585 {
586 struct max3100_port *s = container_of(port,
587 struct max3100_port,
588 port);
589 char b[12];
590
591 dev_dbg(&s->spi->dev, "%s\n", __func__);
592
593 s->conf = MAX3100_RM;
594 s->baud = s->crystal ? 230400 : 115200;
595 s->rx_enabled = 1;
596
597 if (s->suspending)
598 return 0;
599
600 s->force_end_work = 0;
601 s->parity = 0;
602 s->rts = 0;
603
604 sprintf(b, "max3100-%d", s->minor);
605 s->workqueue = create_freezable_workqueue(b);
606 if (!s->workqueue) {
607 dev_warn(&s->spi->dev, "cannot create workqueue\n");
608 return -EBUSY;
609 }
610 INIT_WORK(&s->work, max3100_work);
611
612 if (request_irq(s->irq, max3100_irq,
613 IRQF_TRIGGER_FALLING, "max3100", s) < 0) {
614 dev_warn(&s->spi->dev, "cannot allocate irq %d\n", s->irq);
615 s->irq = 0;
616 destroy_workqueue(s->workqueue);
617 s->workqueue = NULL;
618 return -EBUSY;
619 }
620
621 if (s->loopback) {
622 u16 tx, rx;
623 tx = 0x4001;
624 max3100_sr(s, tx, &rx);
625 }
626
627 if (s->max3100_hw_suspend)
628 s->max3100_hw_suspend(0);
629 s->conf_commit = 1;
630 max3100_dowork(s);
631 /* wait for clock to settle */
632 msleep(50);
633
634 max3100_enable_ms(&s->port);
635
636 return 0;
637 }
638
639 static const char *max3100_type(struct uart_port *port)
640 {
641 struct max3100_port *s = container_of(port,
642 struct max3100_port,
643 port);
644
645 dev_dbg(&s->spi->dev, "%s\n", __func__);
646
647 return s->port.type == PORT_MAX3100 ? "MAX3100" : NULL;
648 }
649
650 static void max3100_release_port(struct uart_port *port)
651 {
652 struct max3100_port *s = container_of(port,
653 struct max3100_port,
654 port);
655
656 dev_dbg(&s->spi->dev, "%s\n", __func__);
657 }
658
659 static void max3100_config_port(struct uart_port *port, int flags)
660 {
661 struct max3100_port *s = container_of(port,
662 struct max3100_port,
663 port);
664
665 dev_dbg(&s->spi->dev, "%s\n", __func__);
666
667 if (flags & UART_CONFIG_TYPE)
668 s->port.type = PORT_MAX3100;
669 }
670
671 static int max3100_verify_port(struct uart_port *port,
672 struct serial_struct *ser)
673 {
674 struct max3100_port *s = container_of(port,
675 struct max3100_port,
676 port);
677 int ret = -EINVAL;
678
679 dev_dbg(&s->spi->dev, "%s\n", __func__);
680
681 if (ser->type == PORT_UNKNOWN || ser->type == PORT_MAX3100)
682 ret = 0;
683 return ret;
684 }
685
686 static void max3100_stop_tx(struct uart_port *port)
687 {
688 struct max3100_port *s = container_of(port,
689 struct max3100_port,
690 port);
691
692 dev_dbg(&s->spi->dev, "%s\n", __func__);
693 }
694
695 static int max3100_request_port(struct uart_port *port)
696 {
697 struct max3100_port *s = container_of(port,
698 struct max3100_port,
699 port);
700
701 dev_dbg(&s->spi->dev, "%s\n", __func__);
702 return 0;
703 }
704
705 static void max3100_break_ctl(struct uart_port *port, int break_state)
706 {
707 struct max3100_port *s = container_of(port,
708 struct max3100_port,
709 port);
710
711 dev_dbg(&s->spi->dev, "%s\n", __func__);
712 }
713
714 static const struct uart_ops max3100_ops = {
715 .tx_empty = max3100_tx_empty,
716 .set_mctrl = max3100_set_mctrl,
717 .get_mctrl = max3100_get_mctrl,
718 .stop_tx = max3100_stop_tx,
719 .start_tx = max3100_start_tx,
720 .stop_rx = max3100_stop_rx,
721 .enable_ms = max3100_enable_ms,
722 .break_ctl = max3100_break_ctl,
723 .startup = max3100_startup,
724 .shutdown = max3100_shutdown,
725 .set_termios = max3100_set_termios,
726 .type = max3100_type,
727 .release_port = max3100_release_port,
728 .request_port = max3100_request_port,
729 .config_port = max3100_config_port,
730 .verify_port = max3100_verify_port,
731 };
732
733 static struct uart_driver max3100_uart_driver = {
734 .owner = THIS_MODULE,
735 .driver_name = "ttyMAX",
736 .dev_name = "ttyMAX",
737 .major = MAX3100_MAJOR,
738 .minor = MAX3100_MINOR,
739 .nr = MAX_MAX3100,
740 };
741 static int uart_driver_registered;
742
743 static int max3100_probe(struct spi_device *spi)
744 {
745 int i, retval;
746 struct plat_max3100 *pdata;
747 u16 tx, rx;
748
749 mutex_lock(&max3100s_lock);
750
751 if (!uart_driver_registered) {
752 retval = uart_register_driver(&max3100_uart_driver);
753 if (retval) {
754 printk(KERN_ERR "Couldn't register max3100 uart driver\n");
755 mutex_unlock(&max3100s_lock);
756 return retval;
757 }
758
759 uart_driver_registered = 1;
760 }
761
762 for (i = 0; i < MAX_MAX3100; i++)
763 if (!max3100s[i])
764 break;
765 if (i == MAX_MAX3100) {
766 dev_warn(&spi->dev, "too many MAX3100 chips\n");
767 mutex_unlock(&max3100s_lock);
768 return -ENOMEM;
769 }
770
771 max3100s[i] = kzalloc(sizeof(struct max3100_port), GFP_KERNEL);
772 if (!max3100s[i]) {
773 dev_warn(&spi->dev,
774 "kmalloc for max3100 structure %d failed!\n", i);
775 mutex_unlock(&max3100s_lock);
776 return -ENOMEM;
777 }
778 max3100s[i]->spi = spi;
779 max3100s[i]->irq = spi->irq;
780 spin_lock_init(&max3100s[i]->conf_lock);
781 spi_set_drvdata(spi, max3100s[i]);
782 pdata = dev_get_platdata(&spi->dev);
783 max3100s[i]->crystal = pdata->crystal;
784 max3100s[i]->loopback = pdata->loopback;
785 max3100s[i]->poll_time = msecs_to_jiffies(pdata->poll_time);
786 if (pdata->poll_time > 0 && max3100s[i]->poll_time == 0)
787 max3100s[i]->poll_time = 1;
788 max3100s[i]->max3100_hw_suspend = pdata->max3100_hw_suspend;
789 max3100s[i]->minor = i;
790 timer_setup(&max3100s[i]->timer, max3100_timeout, 0);
791
792 dev_dbg(&spi->dev, "%s: adding port %d\n", __func__, i);
793 max3100s[i]->port.irq = max3100s[i]->irq;
794 max3100s[i]->port.uartclk = max3100s[i]->crystal ? 3686400 : 1843200;
795 max3100s[i]->port.fifosize = 16;
796 max3100s[i]->port.ops = &max3100_ops;
797 max3100s[i]->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
798 max3100s[i]->port.line = i;
799 max3100s[i]->port.type = PORT_MAX3100;
800 max3100s[i]->port.dev = &spi->dev;
801 retval = uart_add_one_port(&max3100_uart_driver, &max3100s[i]->port);
802 if (retval < 0)
803 dev_warn(&spi->dev,
804 "uart_add_one_port failed for line %d with error %d\n",
805 i, retval);
806
807 /* set shutdown mode to save power. Will be woken-up on open */
808 if (max3100s[i]->max3100_hw_suspend)
809 max3100s[i]->max3100_hw_suspend(1);
810 else {
811 tx = MAX3100_WC | MAX3100_SHDN;
812 max3100_sr(max3100s[i], tx, &rx);
813 }
814 mutex_unlock(&max3100s_lock);
815 return 0;
816 }
817
818 static void max3100_remove(struct spi_device *spi)
819 {
820 struct max3100_port *s = spi_get_drvdata(spi);
821 int i;
822
823 mutex_lock(&max3100s_lock);
824
825 /* find out the index for the chip we are removing */
826 for (i = 0; i < MAX_MAX3100; i++)
827 if (max3100s[i] == s) {
828 dev_dbg(&spi->dev, "%s: removing port %d\n", __func__, i);
829 uart_remove_one_port(&max3100_uart_driver, &max3100s[i]->port);
830 kfree(max3100s[i]);
831 max3100s[i] = NULL;
832 break;
833 }
834
835 WARN_ON(i == MAX_MAX3100);
836
837 /* check if this is the last chip we have */
838 for (i = 0; i < MAX_MAX3100; i++)
839 if (max3100s[i]) {
840 mutex_unlock(&max3100s_lock);
841 return;
842 }
843 pr_debug("removing max3100 driver\n");
844 uart_unregister_driver(&max3100_uart_driver);
845 uart_driver_registered = 0;
846
847 mutex_unlock(&max3100s_lock);
848 }
849
850 #ifdef CONFIG_PM_SLEEP
851
852 static int max3100_suspend(struct device *dev)
853 {
854 struct max3100_port *s = dev_get_drvdata(dev);
855
856 dev_dbg(&s->spi->dev, "%s\n", __func__);
857
858 disable_irq(s->irq);
859
860 s->suspending = 1;
861 uart_suspend_port(&max3100_uart_driver, &s->port);
862
863 if (s->max3100_hw_suspend)
864 s->max3100_hw_suspend(1);
865 else {
866 /* no HW suspend, so do SW one */
867 u16 tx, rx;
868
869 tx = MAX3100_WC | MAX3100_SHDN;
870 max3100_sr(s, tx, &rx);
871 }
872 return 0;
873 }
874
875 static int max3100_resume(struct device *dev)
876 {
877 struct max3100_port *s = dev_get_drvdata(dev);
878
879 dev_dbg(&s->spi->dev, "%s\n", __func__);
880
881 if (s->max3100_hw_suspend)
882 s->max3100_hw_suspend(0);
883 uart_resume_port(&max3100_uart_driver, &s->port);
884 s->suspending = 0;
885
886 enable_irq(s->irq);
887
888 s->conf_commit = 1;
889 if (s->workqueue)
890 max3100_dowork(s);
891
892 return 0;
893 }
894
895 static SIMPLE_DEV_PM_OPS(max3100_pm_ops, max3100_suspend, max3100_resume);
896 #define MAX3100_PM_OPS (&max3100_pm_ops)
897
898 #else
899 #define MAX3100_PM_OPS NULL
900 #endif
901
902 static struct spi_driver max3100_driver = {
903 .driver = {
904 .name = "max3100",
905 .pm = MAX3100_PM_OPS,
906 },
907 .probe = max3100_probe,
908 .remove = max3100_remove,
909 };
910
911 module_spi_driver(max3100_driver);
912
913 MODULE_DESCRIPTION("MAX3100 driver");
914 MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
915 MODULE_LICENSE("GPL");
916 MODULE_ALIAS("spi:max3100");
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