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ASoC: wm8940: Fix check on error code form snd_soc_codec_set_cache_io
[linux-2.6/mini2440.git] / drivers / serial / max3100.c
blob9fd33e5622bdfb32895c7e9dd5882ed6689ba477
1 /*
2 *
3 * Copyright (C) 2008 Christian Pellegrin <chripell@evolware.org>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 *
11 * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have
12 * to use polling for flow control. TX empty IRQ is unusable, since
13 * writing conf clears FIFO buffer and we cannot have this interrupt
14 * always asking us for attention.
15 *
16 * Example platform data:
17
18 static struct plat_max3100 max3100_plat_data = {
19 .loopback = 0,
20 .crystal = 0,
21 .poll_time = 100,
22 };
23
24 static struct spi_board_info spi_board_info[] = {
25 {
26 .modalias = "max3100",
27 .platform_data = &max3100_plat_data,
28 .irq = IRQ_EINT12,
29 .max_speed_hz = 5*1000*1000,
30 .chip_select = 0,
31 },
32 };
33
34 * The initial minor number is 209 in the low-density serial port:
35 * mknod /dev/ttyMAX0 c 204 209
36 */
37
38 #define MAX3100_MAJOR 204
39 #define MAX3100_MINOR 209
40 /* 4 MAX3100s should be enough for everyone */
41 #define MAX_MAX3100 4
42
43 #include <linux/delay.h>
44 #include <linux/device.h>
45 #include <linux/serial_core.h>
46 #include <linux/serial.h>
47 #include <linux/spi/spi.h>
48 #include <linux/freezer.h>
49
50 #include <linux/serial_max3100.h>
51
52 #define MAX3100_C (1<<14)
53 #define MAX3100_D (0<<14)
54 #define MAX3100_W (1<<15)
55 #define MAX3100_RX (0<<15)
56
57 #define MAX3100_WC (MAX3100_W | MAX3100_C)
58 #define MAX3100_RC (MAX3100_RX | MAX3100_C)
59 #define MAX3100_WD (MAX3100_W | MAX3100_D)
60 #define MAX3100_RD (MAX3100_RX | MAX3100_D)
61 #define MAX3100_CMD (3 << 14)
62
63 #define MAX3100_T (1<<14)
64 #define MAX3100_R (1<<15)
65
66 #define MAX3100_FEN (1<<13)
67 #define MAX3100_SHDN (1<<12)
68 #define MAX3100_TM (1<<11)
69 #define MAX3100_RM (1<<10)
70 #define MAX3100_PM (1<<9)
71 #define MAX3100_RAM (1<<8)
72 #define MAX3100_IR (1<<7)
73 #define MAX3100_ST (1<<6)
74 #define MAX3100_PE (1<<5)
75 #define MAX3100_L (1<<4)
76 #define MAX3100_BAUD (0xf)
77
78 #define MAX3100_TE (1<<10)
79 #define MAX3100_RAFE (1<<10)
80 #define MAX3100_RTS (1<<9)
81 #define MAX3100_CTS (1<<9)
82 #define MAX3100_PT (1<<8)
83 #define MAX3100_DATA (0xff)
84
85 #define MAX3100_RT (MAX3100_R | MAX3100_T)
86 #define MAX3100_RTC (MAX3100_RT | MAX3100_CTS | MAX3100_RAFE)
87
88 /* the following simulate a status reg for ignore_status_mask */
89 #define MAX3100_STATUS_PE 1
90 #define MAX3100_STATUS_FE 2
91 #define MAX3100_STATUS_OE 4
92
93 struct max3100_port {
94 struct uart_port port;
95 struct spi_device *spi;
96
97 int cts; /* last CTS received for flow ctrl */
98 int tx_empty; /* last TX empty bit */
99
100 spinlock_t conf_lock; /* shared data */
101 int conf_commit; /* need to make changes */
102 int conf; /* configuration for the MAX31000
103 * (bits 0-7, bits 8-11 are irqs) */
104 int rts_commit; /* need to change rts */
105 int rts; /* rts status */
106 int baud; /* current baud rate */
107
108 int parity; /* keeps track if we should send parity */
109 #define MAX3100_PARITY_ON 1
110 #define MAX3100_PARITY_ODD 2
111 #define MAX3100_7BIT 4
112 int rx_enabled; /* if we should rx chars */
113
114 int irq; /* irq assigned to the max3100 */
115
116 int minor; /* minor number */
117 int crystal; /* 1 if 3.6864Mhz crystal 0 for 1.8432 */
118 int loopback; /* 1 if we are in loopback mode */
119
120 /* for handling irqs: need workqueue since we do spi_sync */
121 struct workqueue_struct *workqueue;
122 struct work_struct work;
123 /* set to 1 to make the workhandler exit as soon as possible */
124 int force_end_work;
125 /* need to know we are suspending to avoid deadlock on workqueue */
126 int suspending;
127
128 /* hook for suspending MAX3100 via dedicated pin */
129 void (*max3100_hw_suspend) (int suspend);
130
131 /* poll time (in ms) for ctrl lines */
132 int poll_time;
133 /* and its timer */
134 struct timer_list timer;
135 };
136
137 static struct max3100_port *max3100s[MAX_MAX3100]; /* the chips */
138 static DEFINE_MUTEX(max3100s_lock); /* race on probe */
139
140 static int max3100_do_parity(struct max3100_port *s, u16 c)
141 {
142 int parity;
143
144 if (s->parity & MAX3100_PARITY_ODD)
145 parity = 1;
146 else
147 parity = 0;
148
149 if (s->parity & MAX3100_7BIT)
150 c &= 0x7f;
151 else
152 c &= 0xff;
153
154 parity = parity ^ (hweight8(c) & 1);
155 return parity;
156 }
157
158 static int max3100_check_parity(struct max3100_port *s, u16 c)
159 {
160 return max3100_do_parity(s, c) == ((c >> 8) & 1);
161 }
162
163 static void max3100_calc_parity(struct max3100_port *s, u16 *c)
164 {
165 if (s->parity & MAX3100_7BIT)
166 *c &= 0x7f;
167 else
168 *c &= 0xff;
169
170 if (s->parity & MAX3100_PARITY_ON)
171 *c |= max3100_do_parity(s, *c) << 8;
172 }
173
174 static void max3100_work(struct work_struct *w);
175
176 static void max3100_dowork(struct max3100_port *s)
177 {
178 if (!s->force_end_work && !work_pending(&s->work) &&
179 !freezing(current) && !s->suspending)
180 queue_work(s->workqueue, &s->work);
181 }
182
183 static void max3100_timeout(unsigned long data)
184 {
185 struct max3100_port *s = (struct max3100_port *)data;
186
187 if (s->port.info) {
188 max3100_dowork(s);
189 mod_timer(&s->timer, jiffies + s->poll_time);
190 }
191 }
192
193 static int max3100_sr(struct max3100_port *s, u16 tx, u16 *rx)
194 {
195 struct spi_message message;
196 u16 etx, erx;
197 int status;
198 struct spi_transfer tran = {
199 .tx_buf = &etx,
200 .rx_buf = &erx,
201 .len = 2,
202 };
203
204 etx = cpu_to_be16(tx);
205 spi_message_init(&message);
206 spi_message_add_tail(&tran, &message);
207 status = spi_sync(s->spi, &message);
208 if (status) {
209 dev_warn(&s->spi->dev, "error while calling spi_sync\n");
210 return -EIO;
211 }
212 *rx = be16_to_cpu(erx);
213 s->tx_empty = (*rx & MAX3100_T) > 0;
214 dev_dbg(&s->spi->dev, "%04x - %04x\n", tx, *rx);
215 return 0;
216 }
217
218 static int max3100_handlerx(struct max3100_port *s, u16 rx)
219 {
220 unsigned int ch, flg, status = 0;
221 int ret = 0, cts;
222
223 if (rx & MAX3100_R && s->rx_enabled) {
224 dev_dbg(&s->spi->dev, "%s\n", __func__);
225 ch = rx & (s->parity & MAX3100_7BIT ? 0x7f : 0xff);
226 if (rx & MAX3100_RAFE) {
227 s->port.icount.frame++;
228 flg = TTY_FRAME;
229 status |= MAX3100_STATUS_FE;
230 } else {
231 if (s->parity & MAX3100_PARITY_ON) {
232 if (max3100_check_parity(s, rx)) {
233 s->port.icount.rx++;
234 flg = TTY_NORMAL;
235 } else {
236 s->port.icount.parity++;
237 flg = TTY_PARITY;
238 status |= MAX3100_STATUS_PE;
239 }
240 } else {
241 s->port.icount.rx++;
242 flg = TTY_NORMAL;
243 }
244 }
245 uart_insert_char(&s->port, status, MAX3100_STATUS_OE, ch, flg);
246 ret = 1;
247 }
248
249 cts = (rx & MAX3100_CTS) > 0;
250 if (s->cts != cts) {
251 s->cts = cts;
252 uart_handle_cts_change(&s->port, cts ? TIOCM_CTS : 0);
253 }
254
255 return ret;
256 }
257
258 static void max3100_work(struct work_struct *w)
259 {
260 struct max3100_port *s = container_of(w, struct max3100_port, work);
261 int rxchars;
262 u16 tx, rx;
263 int conf, cconf, rts, crts;
264 struct circ_buf *xmit = &s->port.info->xmit;
265
266 dev_dbg(&s->spi->dev, "%s\n", __func__);
267
268 rxchars = 0;
269 do {
270 spin_lock(&s->conf_lock);
271 conf = s->conf;
272 cconf = s->conf_commit;
273 s->conf_commit = 0;
274 rts = s->rts;
275 crts = s->rts_commit;
276 s->rts_commit = 0;
277 spin_unlock(&s->conf_lock);
278 if (cconf)
279 max3100_sr(s, MAX3100_WC | conf, &rx);
280 if (crts) {
281 max3100_sr(s, MAX3100_WD | MAX3100_TE |
282 (s->rts ? MAX3100_RTS : 0), &rx);
283 rxchars += max3100_handlerx(s, rx);
284 }
285
286 max3100_sr(s, MAX3100_RD, &rx);
287 rxchars += max3100_handlerx(s, rx);
288
289 if (rx & MAX3100_T) {
290 tx = 0xffff;
291 if (s->port.x_char) {
292 tx = s->port.x_char;
293 s->port.icount.tx++;
294 s->port.x_char = 0;
295 } else if (!uart_circ_empty(xmit) &&
296 !uart_tx_stopped(&s->port)) {
297 tx = xmit->buf[xmit->tail];
298 xmit->tail = (xmit->tail + 1) &
299 (UART_XMIT_SIZE - 1);
300 s->port.icount.tx++;
301 }
302 if (tx != 0xffff) {
303 max3100_calc_parity(s, &tx);
304 tx |= MAX3100_WD | (s->rts ? MAX3100_RTS : 0);
305 max3100_sr(s, tx, &rx);
306 rxchars += max3100_handlerx(s, rx);
307 }
308 }
309
310 if (rxchars > 16 && s->port.info->port.tty != NULL) {
311 tty_flip_buffer_push(s->port.info->port.tty);
312 rxchars = 0;
313 }
314 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
315 uart_write_wakeup(&s->port);
316
317 } while (!s->force_end_work &&
318 !freezing(current) &&
319 ((rx & MAX3100_R) ||
320 (!uart_circ_empty(xmit) &&
321 !uart_tx_stopped(&s->port))));
322
323 if (rxchars > 0 && s->port.info->port.tty != NULL)
324 tty_flip_buffer_push(s->port.info->port.tty);
325 }
326
327 static irqreturn_t max3100_irq(int irqno, void *dev_id)
328 {
329 struct max3100_port *s = dev_id;
330
331 dev_dbg(&s->spi->dev, "%s\n", __func__);
332
333 max3100_dowork(s);
334 return IRQ_HANDLED;
335 }
336
337 static void max3100_enable_ms(struct uart_port *port)
338 {
339 struct max3100_port *s = container_of(port,
340 struct max3100_port,
341 port);
342
343 if (s->poll_time > 0)
344 mod_timer(&s->timer, jiffies);
345 dev_dbg(&s->spi->dev, "%s\n", __func__);
346 }
347
348 static void max3100_start_tx(struct uart_port *port)
349 {
350 struct max3100_port *s = container_of(port,
351 struct max3100_port,
352 port);
353
354 dev_dbg(&s->spi->dev, "%s\n", __func__);
355
356 max3100_dowork(s);
357 }
358
359 static void max3100_stop_rx(struct uart_port *port)
360 {
361 struct max3100_port *s = container_of(port,
362 struct max3100_port,
363 port);
364
365 dev_dbg(&s->spi->dev, "%s\n", __func__);
366
367 s->rx_enabled = 0;
368 spin_lock(&s->conf_lock);
369 s->conf &= ~MAX3100_RM;
370 s->conf_commit = 1;
371 spin_unlock(&s->conf_lock);
372 max3100_dowork(s);
373 }
374
375 static unsigned int max3100_tx_empty(struct uart_port *port)
376 {
377 struct max3100_port *s = container_of(port,
378 struct max3100_port,
379 port);
380
381 dev_dbg(&s->spi->dev, "%s\n", __func__);
382
383 /* may not be truly up-to-date */
384 max3100_dowork(s);
385 return s->tx_empty;
386 }
387
388 static unsigned int max3100_get_mctrl(struct uart_port *port)
389 {
390 struct max3100_port *s = container_of(port,
391 struct max3100_port,
392 port);
393
394 dev_dbg(&s->spi->dev, "%s\n", __func__);
395
396 /* may not be truly up-to-date */
397 max3100_dowork(s);
398 /* always assert DCD and DSR since these lines are not wired */
399 return (s->cts ? TIOCM_CTS : 0) | TIOCM_DSR | TIOCM_CAR;
400 }
401
402 static void max3100_set_mctrl(struct uart_port *port, unsigned int mctrl)
403 {
404 struct max3100_port *s = container_of(port,
405 struct max3100_port,
406 port);
407 int rts;
408
409 dev_dbg(&s->spi->dev, "%s\n", __func__);
410
411 rts = (mctrl & TIOCM_RTS) > 0;
412
413 spin_lock(&s->conf_lock);
414 if (s->rts != rts) {
415 s->rts = rts;
416 s->rts_commit = 1;
417 max3100_dowork(s);
418 }
419 spin_unlock(&s->conf_lock);
420 }
421
422 static void
423 max3100_set_termios(struct uart_port *port, struct ktermios *termios,
424 struct ktermios *old)
425 {
426 struct max3100_port *s = container_of(port,
427 struct max3100_port,
428 port);
429 int baud = 0;
430 unsigned cflag;
431 u32 param_new, param_mask, parity = 0;
432 struct tty_struct *tty = s->port.info->port.tty;
433
434 dev_dbg(&s->spi->dev, "%s\n", __func__);
435 if (!tty)
436 return;
437
438 cflag = termios->c_cflag;
439 param_new = 0;
440 param_mask = 0;
441
442 baud = tty_get_baud_rate(tty);
443 param_new = s->conf & MAX3100_BAUD;
444 switch (baud) {
445 case 300:
446 if (s->crystal)
447 baud = s->baud;
448 else
449 param_new = 15;
450 break;
451 case 600:
452 param_new = 14 + s->crystal;
453 break;
454 case 1200:
455 param_new = 13 + s->crystal;
456 break;
457 case 2400:
458 param_new = 12 + s->crystal;
459 break;
460 case 4800:
461 param_new = 11 + s->crystal;
462 break;
463 case 9600:
464 param_new = 10 + s->crystal;
465 break;
466 case 19200:
467 param_new = 9 + s->crystal;
468 break;
469 case 38400:
470 param_new = 8 + s->crystal;
471 break;
472 case 57600:
473 param_new = 1 + s->crystal;
474 break;
475 case 115200:
476 param_new = 0 + s->crystal;
477 break;
478 case 230400:
479 if (s->crystal)
480 param_new = 0;
481 else
482 baud = s->baud;
483 break;
484 default:
485 baud = s->baud;
486 }
487 tty_encode_baud_rate(tty, baud, baud);
488 s->baud = baud;
489 param_mask |= MAX3100_BAUD;
490
491 if ((cflag & CSIZE) == CS8) {
492 param_new &= ~MAX3100_L;
493 parity &= ~MAX3100_7BIT;
494 } else {
495 param_new |= MAX3100_L;
496 parity |= MAX3100_7BIT;
497 cflag = (cflag & ~CSIZE) | CS7;
498 }
499 param_mask |= MAX3100_L;
500
501 if (cflag & CSTOPB)
502 param_new |= MAX3100_ST;
503 else
504 param_new &= ~MAX3100_ST;
505 param_mask |= MAX3100_ST;
506
507 if (cflag & PARENB) {
508 param_new |= MAX3100_PE;
509 parity |= MAX3100_PARITY_ON;
510 } else {
511 param_new &= ~MAX3100_PE;
512 parity &= ~MAX3100_PARITY_ON;
513 }
514 param_mask |= MAX3100_PE;
515
516 if (cflag & PARODD)
517 parity |= MAX3100_PARITY_ODD;
518 else
519 parity &= ~MAX3100_PARITY_ODD;
520
521 /* mask termios capabilities we don't support */
522 cflag &= ~CMSPAR;
523 termios->c_cflag = cflag;
524
525 s->port.ignore_status_mask = 0;
526 if (termios->c_iflag & IGNPAR)
527 s->port.ignore_status_mask |=
528 MAX3100_STATUS_PE | MAX3100_STATUS_FE |
529 MAX3100_STATUS_OE;
530
531 /* we are sending char from a workqueue so enable */
532 s->port.info->port.tty->low_latency = 1;
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 flush_workqueue(s->workqueue);
568 destroy_workqueue(s->workqueue);
569 s->workqueue = NULL;
570 }
571 if (s->irq)
572 free_irq(s->irq, s);
573
574 /* set shutdown mode to save power */
575 if (s->max3100_hw_suspend)
576 s->max3100_hw_suspend(1);
577 else {
578 u16 tx, rx;
579
580 tx = MAX3100_WC | MAX3100_SHDN;
581 max3100_sr(s, tx, &rx);
582 }
583 }
584
585 static int max3100_startup(struct uart_port *port)
586 {
587 struct max3100_port *s = container_of(port,
588 struct max3100_port,
589 port);
590 char b[12];
591
592 dev_dbg(&s->spi->dev, "%s\n", __func__);
593
594 s->conf = MAX3100_RM;
595 s->baud = s->crystal ? 230400 : 115200;
596 s->rx_enabled = 1;
597
598 if (s->suspending)
599 return 0;
600
601 s->force_end_work = 0;
602 s->parity = 0;
603 s->rts = 0;
604
605 sprintf(b, "max3100-%d", s->minor);
606 s->workqueue = create_freezeable_workqueue(b);
607 if (!s->workqueue) {
608 dev_warn(&s->spi->dev, "cannot create workqueue\n");
609 return -EBUSY;
610 }
611 INIT_WORK(&s->work, max3100_work);
612
613 if (request_irq(s->irq, max3100_irq,
614 IRQF_TRIGGER_FALLING, "max3100", s) < 0) {
615 dev_warn(&s->spi->dev, "cannot allocate irq %d\n", s->irq);
616 s->irq = 0;
617 destroy_workqueue(s->workqueue);
618 s->workqueue = NULL;
619 return -EBUSY;
620 }
621
622 if (s->loopback) {
623 u16 tx, rx;
624 tx = 0x4001;
625 max3100_sr(s, tx, &rx);
626 }
627
628 if (s->max3100_hw_suspend)
629 s->max3100_hw_suspend(0);
630 s->conf_commit = 1;
631 max3100_dowork(s);
632 /* wait for clock to settle */
633 msleep(50);
634
635 max3100_enable_ms(&s->port);
636
637 return 0;
638 }
639
640 static const char *max3100_type(struct uart_port *port)
641 {
642 struct max3100_port *s = container_of(port,
643 struct max3100_port,
644 port);
645
646 dev_dbg(&s->spi->dev, "%s\n", __func__);
647
648 return s->port.type == PORT_MAX3100 ? "MAX3100" : NULL;
649 }
650
651 static void max3100_release_port(struct uart_port *port)
652 {
653 struct max3100_port *s = container_of(port,
654 struct max3100_port,
655 port);
656
657 dev_dbg(&s->spi->dev, "%s\n", __func__);
658 }
659
660 static void max3100_config_port(struct uart_port *port, int flags)
661 {
662 struct max3100_port *s = container_of(port,
663 struct max3100_port,
664 port);
665
666 dev_dbg(&s->spi->dev, "%s\n", __func__);
667
668 if (flags & UART_CONFIG_TYPE)
669 s->port.type = PORT_MAX3100;
670 }
671
672 static int max3100_verify_port(struct uart_port *port,
673 struct serial_struct *ser)
674 {
675 struct max3100_port *s = container_of(port,
676 struct max3100_port,
677 port);
678 int ret = -EINVAL;
679
680 dev_dbg(&s->spi->dev, "%s\n", __func__);
681
682 if (ser->type == PORT_UNKNOWN || ser->type == PORT_MAX3100)
683 ret = 0;
684 return ret;
685 }
686
687 static void max3100_stop_tx(struct uart_port *port)
688 {
689 struct max3100_port *s = container_of(port,
690 struct max3100_port,
691 port);
692
693 dev_dbg(&s->spi->dev, "%s\n", __func__);
694 }
695
696 static int max3100_request_port(struct uart_port *port)
697 {
698 struct max3100_port *s = container_of(port,
699 struct max3100_port,
700 port);
701
702 dev_dbg(&s->spi->dev, "%s\n", __func__);
703 return 0;
704 }
705
706 static void max3100_break_ctl(struct uart_port *port, int break_state)
707 {
708 struct max3100_port *s = container_of(port,
709 struct max3100_port,
710 port);
711
712 dev_dbg(&s->spi->dev, "%s\n", __func__);
713 }
714
715 static struct uart_ops max3100_ops = {
716 .tx_empty = max3100_tx_empty,
717 .set_mctrl = max3100_set_mctrl,
718 .get_mctrl = max3100_get_mctrl,
719 .stop_tx = max3100_stop_tx,
720 .start_tx = max3100_start_tx,
721 .stop_rx = max3100_stop_rx,
722 .enable_ms = max3100_enable_ms,
723 .break_ctl = max3100_break_ctl,
724 .startup = max3100_startup,
725 .shutdown = max3100_shutdown,
726 .set_termios = max3100_set_termios,
727 .type = max3100_type,
728 .release_port = max3100_release_port,
729 .request_port = max3100_request_port,
730 .config_port = max3100_config_port,
731 .verify_port = max3100_verify_port,
732 };
733
734 static struct uart_driver max3100_uart_driver = {
735 .owner = THIS_MODULE,
736 .driver_name = "ttyMAX",
737 .dev_name = "ttyMAX",
738 .major = MAX3100_MAJOR,
739 .minor = MAX3100_MINOR,
740 .nr = MAX_MAX3100,
741 };
742 static int uart_driver_registered;
743
744 static int __devinit max3100_probe(struct spi_device *spi)
745 {
746 int i, retval;
747 struct plat_max3100 *pdata;
748 u16 tx, rx;
749
750 mutex_lock(&max3100s_lock);
751
752 if (!uart_driver_registered) {
753 uart_driver_registered = 1;
754 retval = uart_register_driver(&max3100_uart_driver);
755 if (retval) {
756 printk(KERN_ERR "Couldn't register max3100 uart driver\n");
757 mutex_unlock(&max3100s_lock);
758 return retval;
759 }
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 dev_set_drvdata(&spi->dev, max3100s[i]);
782 pdata = spi->dev.platform_data;
783 max3100s[i]->crystal = pdata->crystal;
784 max3100s[i]->loopback = pdata->loopback;
785 max3100s[i]->poll_time = pdata->poll_time * HZ / 1000;
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 init_timer(&max3100s[i]->timer);
791 max3100s[i]->timer.function = max3100_timeout;
792 max3100s[i]->timer.data = (unsigned long) max3100s[i];
793
794 dev_dbg(&spi->dev, "%s: adding port %d\n", __func__, i);
795 max3100s[i]->port.irq = max3100s[i]->irq;
796 max3100s[i]->port.uartclk = max3100s[i]->crystal ? 3686400 : 1843200;
797 max3100s[i]->port.fifosize = 16;
798 max3100s[i]->port.ops = &max3100_ops;
799 max3100s[i]->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
800 max3100s[i]->port.line = i;
801 max3100s[i]->port.type = PORT_MAX3100;
802 max3100s[i]->port.dev = &spi->dev;
803 retval = uart_add_one_port(&max3100_uart_driver, &max3100s[i]->port);
804 if (retval < 0)
805 dev_warn(&spi->dev,
806 "uart_add_one_port failed for line %d with error %d\n",
807 i, retval);
808
809 /* set shutdown mode to save power. Will be woken-up on open */
810 if (max3100s[i]->max3100_hw_suspend)
811 max3100s[i]->max3100_hw_suspend(1);
812 else {
813 tx = MAX3100_WC | MAX3100_SHDN;
814 max3100_sr(max3100s[i], tx, &rx);
815 }
816 mutex_unlock(&max3100s_lock);
817 return 0;
818 }
819
820 static int __devexit max3100_remove(struct spi_device *spi)
821 {
822 struct max3100_port *s = dev_get_drvdata(&spi->dev);
823 int i;
824
825 mutex_lock(&max3100s_lock);
826
827 /* find out the index for the chip we are removing */
828 for (i = 0; i < MAX_MAX3100; i++)
829 if (max3100s[i] == s)
830 break;
831
832 dev_dbg(&spi->dev, "%s: removing port %d\n", __func__, i);
833 uart_remove_one_port(&max3100_uart_driver, &max3100s[i]->port);
834 kfree(max3100s[i]);
835 max3100s[i] = NULL;
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 0;
842 }
843 pr_debug("removing max3100 driver\n");
844 uart_unregister_driver(&max3100_uart_driver);
845
846 mutex_unlock(&max3100s_lock);
847 return 0;
848 }
849
850 #ifdef CONFIG_PM
851
852 static int max3100_suspend(struct spi_device *spi, pm_message_t state)
853 {
854 struct max3100_port *s = dev_get_drvdata(&spi->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 spi_device *spi)
876 {
877 struct max3100_port *s = dev_get_drvdata(&spi->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 #else
896 #define max3100_suspend NULL
897 #define max3100_resume NULL
898 #endif
899
900 static struct spi_driver max3100_driver = {
901 .driver = {
902 .name = "max3100",
903 .bus = &spi_bus_type,
904 .owner = THIS_MODULE,
905 },
906
907 .probe = max3100_probe,
908 .remove = __devexit_p(max3100_remove),
909 .suspend = max3100_suspend,
910 .resume = max3100_resume,
911 };
912
913 static int __init max3100_init(void)
914 {
915 return spi_register_driver(&max3100_driver);
916 }
917 module_init(max3100_init);
918
919 static void __exit max3100_exit(void)
920 {
921 spi_unregister_driver(&max3100_driver);
922 }
923 module_exit(max3100_exit);
924
925 MODULE_DESCRIPTION("MAX3100 driver");
926 MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
927 MODULE_LICENSE("GPL");
Support for the Chinese Samsung S3C2440 based development boards