Merge commit 'v2.6.28-rc9' into next
[linux-2.6] / drivers / serial / bfin_5xx.c
1 /*
2  * Blackfin On-Chip Serial Driver
3  *
4  * Copyright 2006-2008 Analog Devices Inc.
5  *
6  * Enter bugs at http://blackfin.uclinux.org/
7  *
8  * Licensed under the GPL-2 or later.
9  */
10
11 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
12 #define SUPPORT_SYSRQ
13 #endif
14
15 #include <linux/module.h>
16 #include <linux/ioport.h>
17 #include <linux/init.h>
18 #include <linux/console.h>
19 #include <linux/sysrq.h>
20 #include <linux/platform_device.h>
21 #include <linux/tty.h>
22 #include <linux/tty_flip.h>
23 #include <linux/serial_core.h>
24
25 #ifdef CONFIG_KGDB_UART
26 #include <linux/kgdb.h>
27 #include <asm/irq_regs.h>
28 #endif
29
30 #include <asm/gpio.h>
31 #include <mach/bfin_serial_5xx.h>
32
33 #ifdef CONFIG_SERIAL_BFIN_DMA
34 #include <linux/dma-mapping.h>
35 #include <asm/io.h>
36 #include <asm/irq.h>
37 #include <asm/cacheflush.h>
38 #endif
39
40 /* UART name and device definitions */
41 #define BFIN_SERIAL_NAME        "ttyBF"
42 #define BFIN_SERIAL_MAJOR       204
43 #define BFIN_SERIAL_MINOR       64
44
45 static struct bfin_serial_port bfin_serial_ports[BFIN_UART_NR_PORTS];
46 static int nr_active_ports = ARRAY_SIZE(bfin_serial_resource);
47
48 /*
49  * Setup for console. Argument comes from the menuconfig
50  */
51 #define DMA_RX_XCOUNT           512
52 #define DMA_RX_YCOUNT           (PAGE_SIZE / DMA_RX_XCOUNT)
53
54 #define DMA_RX_FLUSH_JIFFIES    (HZ / 50)
55 #define CTS_CHECK_JIFFIES       (HZ / 50)
56
57 #ifdef CONFIG_SERIAL_BFIN_DMA
58 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
59 #else
60 static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
61 #endif
62
63 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
64
65 /*
66  * interrupts are disabled on entry
67  */
68 static void bfin_serial_stop_tx(struct uart_port *port)
69 {
70         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
71         struct circ_buf *xmit = &uart->port.info->xmit;
72
73         while (!(UART_GET_LSR(uart) & TEMT))
74                 cpu_relax();
75
76 #ifdef CONFIG_SERIAL_BFIN_DMA
77         disable_dma(uart->tx_dma_channel);
78         xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
79         uart->port.icount.tx += uart->tx_count;
80         uart->tx_count = 0;
81         uart->tx_done = 1;
82 #else
83 #ifdef CONFIG_BF54x
84         /* Clear TFI bit */
85         UART_PUT_LSR(uart, TFI);
86 #endif
87         UART_CLEAR_IER(uart, ETBEI);
88 #endif
89 }
90
91 /*
92  * port is locked and interrupts are disabled
93  */
94 static void bfin_serial_start_tx(struct uart_port *port)
95 {
96         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
97
98 #ifdef CONFIG_SERIAL_BFIN_DMA
99         if (uart->tx_done)
100                 bfin_serial_dma_tx_chars(uart);
101 #else
102         UART_SET_IER(uart, ETBEI);
103         bfin_serial_tx_chars(uart);
104 #endif
105 }
106
107 /*
108  * Interrupts are enabled
109  */
110 static void bfin_serial_stop_rx(struct uart_port *port)
111 {
112         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
113 #ifdef CONFIG_KGDB_UART
114         if (uart->port.line != CONFIG_KGDB_UART_PORT)
115 #endif
116         UART_CLEAR_IER(uart, ERBFI);
117 }
118
119 /*
120  * Set the modem control timer to fire immediately.
121  */
122 static void bfin_serial_enable_ms(struct uart_port *port)
123 {
124 }
125
126 #ifdef CONFIG_KGDB_UART
127 static int kgdb_entry_state;
128
129 void kgdb_put_debug_char(int chr)
130 {
131         struct bfin_serial_port *uart;
132
133         if (CONFIG_KGDB_UART_PORT < 0
134                 || CONFIG_KGDB_UART_PORT >= BFIN_UART_NR_PORTS)
135                 uart = &bfin_serial_ports[0];
136         else
137                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
138
139         while (!(UART_GET_LSR(uart) & THRE)) {
140                 SSYNC();
141         }
142
143         UART_CLEAR_DLAB(uart);
144         UART_PUT_CHAR(uart, (unsigned char)chr);
145         SSYNC();
146 }
147
148 int kgdb_get_debug_char(void)
149 {
150         struct bfin_serial_port *uart;
151         unsigned char chr;
152
153         if (CONFIG_KGDB_UART_PORT < 0
154                 || CONFIG_KGDB_UART_PORT >= BFIN_UART_NR_PORTS)
155                 uart = &bfin_serial_ports[0];
156         else
157                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
158
159         while(!(UART_GET_LSR(uart) & DR)) {
160                 SSYNC();
161         }
162         UART_CLEAR_DLAB(uart);
163         chr = UART_GET_CHAR(uart);
164         SSYNC();
165
166         return chr;
167 }
168 #endif
169
170 #if ANOMALY_05000363 && defined(CONFIG_SERIAL_BFIN_PIO)
171 # define UART_GET_ANOMALY_THRESHOLD(uart)    ((uart)->anomaly_threshold)
172 # define UART_SET_ANOMALY_THRESHOLD(uart, v) ((uart)->anomaly_threshold = (v))
173 #else
174 # define UART_GET_ANOMALY_THRESHOLD(uart)    0
175 # define UART_SET_ANOMALY_THRESHOLD(uart, v)
176 #endif
177
178 #ifdef CONFIG_SERIAL_BFIN_PIO
179 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
180 {
181         struct tty_struct *tty = uart->port.info->port.tty;
182         unsigned int status, ch, flg;
183         static struct timeval anomaly_start = { .tv_sec = 0 };
184
185         status = UART_GET_LSR(uart);
186         UART_CLEAR_LSR(uart);
187
188         ch = UART_GET_CHAR(uart);
189         uart->port.icount.rx++;
190
191 #ifdef CONFIG_KGDB_UART
192         if (uart->port.line == CONFIG_KGDB_UART_PORT) {
193                 struct pt_regs *regs = get_irq_regs();
194                 if (uart->port.cons->index == CONFIG_KGDB_UART_PORT && ch == 0x1) { /* Ctrl + A */
195                         kgdb_breakkey_pressed(regs);
196                         return;
197                 } else if (kgdb_entry_state == 0 && ch == '$') {/* connection from KGDB */
198                         kgdb_entry_state = 1;
199                 } else if (kgdb_entry_state == 1 && ch == 'q') {
200                         kgdb_entry_state = 0;
201                         kgdb_breakkey_pressed(regs);
202                         return;
203                 } else if (ch == 0x3) {/* Ctrl + C */
204                         kgdb_entry_state = 0;
205                         kgdb_breakkey_pressed(regs);
206                         return;
207                 } else {
208                         kgdb_entry_state = 0;
209                 }
210         }
211 #endif
212
213         if (ANOMALY_05000363) {
214                 /* The BF533 (and BF561) family of processors have a nice anomaly
215                  * where they continuously generate characters for a "single" break.
216                  * We have to basically ignore this flood until the "next" valid
217                  * character comes across.  Due to the nature of the flood, it is
218                  * not possible to reliably catch bytes that are sent too quickly
219                  * after this break.  So application code talking to the Blackfin
220                  * which sends a break signal must allow at least 1.5 character
221                  * times after the end of the break for things to stabilize.  This
222                  * timeout was picked as it must absolutely be larger than 1
223                  * character time +/- some percent.  So 1.5 sounds good.  All other
224                  * Blackfin families operate properly.  Woo.
225                  */
226                 if (anomaly_start.tv_sec) {
227                         struct timeval curr;
228                         suseconds_t usecs;
229
230                         if ((~ch & (~ch + 1)) & 0xff)
231                                 goto known_good_char;
232
233                         do_gettimeofday(&curr);
234                         if (curr.tv_sec - anomaly_start.tv_sec > 1)
235                                 goto known_good_char;
236
237                         usecs = 0;
238                         if (curr.tv_sec != anomaly_start.tv_sec)
239                                 usecs += USEC_PER_SEC;
240                         usecs += curr.tv_usec - anomaly_start.tv_usec;
241
242                         if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
243                                 goto known_good_char;
244
245                         if (ch)
246                                 anomaly_start.tv_sec = 0;
247                         else
248                                 anomaly_start = curr;
249
250                         return;
251
252  known_good_char:
253                         anomaly_start.tv_sec = 0;
254                 }
255         }
256
257         if (status & BI) {
258                 if (ANOMALY_05000363)
259                         if (bfin_revid() < 5)
260                                 do_gettimeofday(&anomaly_start);
261                 uart->port.icount.brk++;
262                 if (uart_handle_break(&uart->port))
263                         goto ignore_char;
264                 status &= ~(PE | FE);
265         }
266         if (status & PE)
267                 uart->port.icount.parity++;
268         if (status & OE)
269                 uart->port.icount.overrun++;
270         if (status & FE)
271                 uart->port.icount.frame++;
272
273         status &= uart->port.read_status_mask;
274
275         if (status & BI)
276                 flg = TTY_BREAK;
277         else if (status & PE)
278                 flg = TTY_PARITY;
279         else if (status & FE)
280                 flg = TTY_FRAME;
281         else
282                 flg = TTY_NORMAL;
283
284         if (uart_handle_sysrq_char(&uart->port, ch))
285                 goto ignore_char;
286
287         uart_insert_char(&uart->port, status, OE, ch, flg);
288
289  ignore_char:
290         tty_flip_buffer_push(tty);
291 }
292
293 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
294 {
295         struct circ_buf *xmit = &uart->port.info->xmit;
296
297         /*
298          * Check the modem control lines before
299          * transmitting anything.
300          */
301         bfin_serial_mctrl_check(uart);
302
303         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
304 #ifdef CONFIG_BF54x
305                 /* Clear TFI bit */
306                 UART_PUT_LSR(uart, TFI);
307 #endif
308                 UART_CLEAR_IER(uart, ETBEI);
309                 return;
310         }
311
312         if (uart->port.x_char) {
313                 UART_PUT_CHAR(uart, uart->port.x_char);
314                 uart->port.icount.tx++;
315                 uart->port.x_char = 0;
316         }
317
318         while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
319                 UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
320                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
321                 uart->port.icount.tx++;
322                 SSYNC();
323         }
324
325         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
326                 uart_write_wakeup(&uart->port);
327 }
328
329 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
330 {
331         struct bfin_serial_port *uart = dev_id;
332
333         spin_lock(&uart->port.lock);
334         while (UART_GET_LSR(uart) & DR)
335                 bfin_serial_rx_chars(uart);
336         spin_unlock(&uart->port.lock);
337
338         return IRQ_HANDLED;
339 }
340
341 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
342 {
343         struct bfin_serial_port *uart = dev_id;
344
345         spin_lock(&uart->port.lock);
346         if (UART_GET_LSR(uart) & THRE)
347                 bfin_serial_tx_chars(uart);
348         spin_unlock(&uart->port.lock);
349
350         return IRQ_HANDLED;
351 }
352 #endif
353
354 #ifdef CONFIG_SERIAL_BFIN_DMA
355 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
356 {
357         struct circ_buf *xmit = &uart->port.info->xmit;
358
359         uart->tx_done = 0;
360
361         /*
362          * Check the modem control lines before
363          * transmitting anything.
364          */
365         bfin_serial_mctrl_check(uart);
366
367         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
368                 uart->tx_count = 0;
369                 uart->tx_done = 1;
370                 return;
371         }
372
373         if (uart->port.x_char) {
374                 UART_PUT_CHAR(uart, uart->port.x_char);
375                 uart->port.icount.tx++;
376                 uart->port.x_char = 0;
377         }
378
379         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
380         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
381                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
382         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
383                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
384         set_dma_config(uart->tx_dma_channel,
385                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
386                         INTR_ON_BUF,
387                         DIMENSION_LINEAR,
388                         DATA_SIZE_8,
389                         DMA_SYNC_RESTART));
390         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
391         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
392         set_dma_x_modify(uart->tx_dma_channel, 1);
393         enable_dma(uart->tx_dma_channel);
394
395         UART_SET_IER(uart, ETBEI);
396 }
397
398 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
399 {
400         struct tty_struct *tty = uart->port.info->port.tty;
401         int i, flg, status;
402
403         status = UART_GET_LSR(uart);
404         UART_CLEAR_LSR(uart);
405
406         uart->port.icount.rx +=
407                 CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
408                 UART_XMIT_SIZE);
409
410         if (status & BI) {
411                 uart->port.icount.brk++;
412                 if (uart_handle_break(&uart->port))
413                         goto dma_ignore_char;
414                 status &= ~(PE | FE);
415         }
416         if (status & PE)
417                 uart->port.icount.parity++;
418         if (status & OE)
419                 uart->port.icount.overrun++;
420         if (status & FE)
421                 uart->port.icount.frame++;
422
423         status &= uart->port.read_status_mask;
424
425         if (status & BI)
426                 flg = TTY_BREAK;
427         else if (status & PE)
428                 flg = TTY_PARITY;
429         else if (status & FE)
430                 flg = TTY_FRAME;
431         else
432                 flg = TTY_NORMAL;
433
434         for (i = uart->rx_dma_buf.tail; i != uart->rx_dma_buf.head; i++) {
435                 if (i >= UART_XMIT_SIZE)
436                         i = 0;
437                 if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
438                         uart_insert_char(&uart->port, status, OE,
439                                 uart->rx_dma_buf.buf[i], flg);
440         }
441
442  dma_ignore_char:
443         tty_flip_buffer_push(tty);
444 }
445
446 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
447 {
448         int x_pos, pos;
449
450         uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
451         x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
452         uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
453         if (uart->rx_dma_nrows == DMA_RX_YCOUNT)
454                 uart->rx_dma_nrows = 0;
455         x_pos = DMA_RX_XCOUNT - x_pos;
456         if (x_pos == DMA_RX_XCOUNT)
457                 x_pos = 0;
458
459         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
460         if (pos != uart->rx_dma_buf.tail) {
461                 uart->rx_dma_buf.head = pos;
462                 bfin_serial_dma_rx_chars(uart);
463                 uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
464         }
465
466         mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
467 }
468
469 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
470 {
471         struct bfin_serial_port *uart = dev_id;
472         struct circ_buf *xmit = &uart->port.info->xmit;
473
474         spin_lock(&uart->port.lock);
475         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
476                 disable_dma(uart->tx_dma_channel);
477                 clear_dma_irqstat(uart->tx_dma_channel);
478                 UART_CLEAR_IER(uart, ETBEI);
479                 xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
480                 uart->port.icount.tx += uart->tx_count;
481
482                 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
483                         uart_write_wakeup(&uart->port);
484
485                 bfin_serial_dma_tx_chars(uart);
486         }
487
488         spin_unlock(&uart->port.lock);
489         return IRQ_HANDLED;
490 }
491
492 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
493 {
494         struct bfin_serial_port *uart = dev_id;
495         unsigned short irqstat;
496
497         spin_lock(&uart->port.lock);
498         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
499         clear_dma_irqstat(uart->rx_dma_channel);
500         spin_unlock(&uart->port.lock);
501
502         mod_timer(&(uart->rx_dma_timer), jiffies);
503
504         return IRQ_HANDLED;
505 }
506 #endif
507
508 /*
509  * Return TIOCSER_TEMT when transmitter is not busy.
510  */
511 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
512 {
513         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
514         unsigned short lsr;
515
516         lsr = UART_GET_LSR(uart);
517         if (lsr & TEMT)
518                 return TIOCSER_TEMT;
519         else
520                 return 0;
521 }
522
523 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
524 {
525 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
526         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
527         if (uart->cts_pin < 0)
528                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
529
530         if (UART_GET_CTS(uart))
531                 return TIOCM_DSR | TIOCM_CAR;
532         else
533 #endif
534                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
535 }
536
537 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
538 {
539 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
540         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
541         if (uart->rts_pin < 0)
542                 return;
543
544         if (mctrl & TIOCM_RTS)
545                 UART_CLEAR_RTS(uart);
546         else
547                 UART_SET_RTS(uart);
548 #endif
549 }
550
551 /*
552  * Handle any change of modem status signal since we were last called.
553  */
554 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
555 {
556 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
557         unsigned int status;
558         struct uart_info *info = uart->port.info;
559         struct tty_struct *tty = info->port.tty;
560
561         status = bfin_serial_get_mctrl(&uart->port);
562         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
563         if (!(status & TIOCM_CTS)) {
564                 tty->hw_stopped = 1;
565                 uart->cts_timer.data = (unsigned long)(uart);
566                 uart->cts_timer.function = (void *)bfin_serial_mctrl_check;
567                 uart->cts_timer.expires = jiffies + CTS_CHECK_JIFFIES;
568                 add_timer(&(uart->cts_timer));
569         } else {
570                 tty->hw_stopped = 0;
571         }
572 #endif
573 }
574
575 /*
576  * Interrupts are always disabled.
577  */
578 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
579 {
580         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
581         u16 lcr = UART_GET_LCR(uart);
582         if (break_state)
583                 lcr |= SB;
584         else
585                 lcr &= ~SB;
586         UART_PUT_LCR(uart, lcr);
587         SSYNC();
588 }
589
590 static int bfin_serial_startup(struct uart_port *port)
591 {
592         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
593
594 #ifdef CONFIG_SERIAL_BFIN_DMA
595         dma_addr_t dma_handle;
596
597         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
598                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
599                 return -EBUSY;
600         }
601
602         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
603                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
604                 free_dma(uart->rx_dma_channel);
605                 return -EBUSY;
606         }
607
608         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
609         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
610
611         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
612         uart->rx_dma_buf.head = 0;
613         uart->rx_dma_buf.tail = 0;
614         uart->rx_dma_nrows = 0;
615
616         set_dma_config(uart->rx_dma_channel,
617                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
618                                 INTR_ON_ROW, DIMENSION_2D,
619                                 DATA_SIZE_8,
620                                 DMA_SYNC_RESTART));
621         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
622         set_dma_x_modify(uart->rx_dma_channel, 1);
623         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
624         set_dma_y_modify(uart->rx_dma_channel, 1);
625         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
626         enable_dma(uart->rx_dma_channel);
627
628         uart->rx_dma_timer.data = (unsigned long)(uart);
629         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
630         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
631         add_timer(&(uart->rx_dma_timer));
632 #else
633         if (request_irq(uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
634              "BFIN_UART_RX", uart)) {
635 # ifdef CONFIG_KGDB_UART
636                 if (uart->port.line != CONFIG_KGDB_UART_PORT) {
637 # endif
638                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
639                 return -EBUSY;
640 # ifdef CONFIG_KGDB_UART
641                 }
642 # endif
643         }
644
645         if (request_irq
646             (uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
647              "BFIN_UART_TX", uart)) {
648                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
649                 free_irq(uart->port.irq, uart);
650                 return -EBUSY;
651         }
652
653 # ifdef CONFIG_BF54x
654         {
655                 unsigned uart_dma_ch_rx, uart_dma_ch_tx;
656
657                 switch (uart->port.irq) {
658                 case IRQ_UART3_RX:
659                         uart_dma_ch_rx = CH_UART3_RX;
660                         uart_dma_ch_tx = CH_UART3_TX;
661                         break;
662                 case IRQ_UART2_RX:
663                         uart_dma_ch_rx = CH_UART2_RX;
664                         uart_dma_ch_tx = CH_UART2_TX;
665                         break;
666                 default:
667                         uart_dma_ch_rx = uart_dma_ch_tx = 0;
668                         break;
669                 };
670
671                 if (uart_dma_ch_rx &&
672                         request_dma(uart_dma_ch_rx, "BFIN_UART_RX") < 0) {
673                         printk(KERN_NOTICE"Fail to attach UART interrupt\n");
674                         free_irq(uart->port.irq, uart);
675                         free_irq(uart->port.irq + 1, uart);
676                         return -EBUSY;
677                 }
678                 if (uart_dma_ch_tx &&
679                         request_dma(uart_dma_ch_tx, "BFIN_UART_TX") < 0) {
680                         printk(KERN_NOTICE "Fail to attach UART interrupt\n");
681                         free_dma(uart_dma_ch_rx);
682                         free_irq(uart->port.irq, uart);
683                         free_irq(uart->port.irq + 1, uart);
684                         return -EBUSY;
685                 }
686         }
687 # endif
688 #endif
689         UART_SET_IER(uart, ERBFI);
690         return 0;
691 }
692
693 static void bfin_serial_shutdown(struct uart_port *port)
694 {
695         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
696
697 #ifdef CONFIG_SERIAL_BFIN_DMA
698         disable_dma(uart->tx_dma_channel);
699         free_dma(uart->tx_dma_channel);
700         disable_dma(uart->rx_dma_channel);
701         free_dma(uart->rx_dma_channel);
702         del_timer(&(uart->rx_dma_timer));
703         dma_free_coherent(NULL, PAGE_SIZE, uart->rx_dma_buf.buf, 0);
704 #else
705 #ifdef CONFIG_BF54x
706         switch (uart->port.irq) {
707         case IRQ_UART3_RX:
708                 free_dma(CH_UART3_RX);
709                 free_dma(CH_UART3_TX);
710                 break;
711         case IRQ_UART2_RX:
712                 free_dma(CH_UART2_RX);
713                 free_dma(CH_UART2_TX);
714                 break;
715         default:
716                 break;
717         };
718 #endif
719 #ifdef  CONFIG_KGDB_UART
720         if (uart->port.line != CONFIG_KGDB_UART_PORT)
721 #endif
722         free_irq(uart->port.irq, uart);
723         free_irq(uart->port.irq+1, uart);
724 #endif
725 }
726
727 static void
728 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
729                    struct ktermios *old)
730 {
731         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
732         unsigned long flags;
733         unsigned int baud, quot;
734         unsigned short val, ier, lcr = 0;
735
736         switch (termios->c_cflag & CSIZE) {
737         case CS8:
738                 lcr = WLS(8);
739                 break;
740         case CS7:
741                 lcr = WLS(7);
742                 break;
743         case CS6:
744                 lcr = WLS(6);
745                 break;
746         case CS5:
747                 lcr = WLS(5);
748                 break;
749         default:
750                 printk(KERN_ERR "%s: word lengh not supported\n",
751                         __func__);
752         }
753
754         if (termios->c_cflag & CSTOPB)
755                 lcr |= STB;
756         if (termios->c_cflag & PARENB)
757                 lcr |= PEN;
758         if (!(termios->c_cflag & PARODD))
759                 lcr |= EPS;
760         if (termios->c_cflag & CMSPAR)
761                 lcr |= STP;
762
763         port->read_status_mask = OE;
764         if (termios->c_iflag & INPCK)
765                 port->read_status_mask |= (FE | PE);
766         if (termios->c_iflag & (BRKINT | PARMRK))
767                 port->read_status_mask |= BI;
768
769         /*
770          * Characters to ignore
771          */
772         port->ignore_status_mask = 0;
773         if (termios->c_iflag & IGNPAR)
774                 port->ignore_status_mask |= FE | PE;
775         if (termios->c_iflag & IGNBRK) {
776                 port->ignore_status_mask |= BI;
777                 /*
778                  * If we're ignoring parity and break indicators,
779                  * ignore overruns too (for real raw support).
780                  */
781                 if (termios->c_iflag & IGNPAR)
782                         port->ignore_status_mask |= OE;
783         }
784
785         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
786         quot = uart_get_divisor(port, baud);
787         spin_lock_irqsave(&uart->port.lock, flags);
788
789         UART_SET_ANOMALY_THRESHOLD(uart, USEC_PER_SEC / baud * 15);
790
791         /* Disable UART */
792         ier = UART_GET_IER(uart);
793         UART_DISABLE_INTS(uart);
794
795         /* Set DLAB in LCR to Access DLL and DLH */
796         UART_SET_DLAB(uart);
797
798         UART_PUT_DLL(uart, quot & 0xFF);
799         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
800         SSYNC();
801
802         /* Clear DLAB in LCR to Access THR RBR IER */
803         UART_CLEAR_DLAB(uart);
804
805         UART_PUT_LCR(uart, lcr);
806
807         /* Enable UART */
808         UART_ENABLE_INTS(uart, ier);
809
810         val = UART_GET_GCTL(uart);
811         val |= UCEN;
812         UART_PUT_GCTL(uart, val);
813
814         /* Port speed changed, update the per-port timeout. */
815         uart_update_timeout(port, termios->c_cflag, baud);
816
817         spin_unlock_irqrestore(&uart->port.lock, flags);
818 }
819
820 static const char *bfin_serial_type(struct uart_port *port)
821 {
822         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
823
824         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
825 }
826
827 /*
828  * Release the memory region(s) being used by 'port'.
829  */
830 static void bfin_serial_release_port(struct uart_port *port)
831 {
832 }
833
834 /*
835  * Request the memory region(s) being used by 'port'.
836  */
837 static int bfin_serial_request_port(struct uart_port *port)
838 {
839         return 0;
840 }
841
842 /*
843  * Configure/autoconfigure the port.
844  */
845 static void bfin_serial_config_port(struct uart_port *port, int flags)
846 {
847         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
848
849         if (flags & UART_CONFIG_TYPE &&
850             bfin_serial_request_port(&uart->port) == 0)
851                 uart->port.type = PORT_BFIN;
852 }
853
854 /*
855  * Verify the new serial_struct (for TIOCSSERIAL).
856  * The only change we allow are to the flags and type, and
857  * even then only between PORT_BFIN and PORT_UNKNOWN
858  */
859 static int
860 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
861 {
862         return 0;
863 }
864
865 /*
866  * Enable the IrDA function if tty->ldisc.num is N_IRDA.
867  * In other cases, disable IrDA function.
868  */
869 static void bfin_serial_set_ldisc(struct uart_port *port)
870 {
871         int line = port->line;
872         unsigned short val;
873
874         if (line >= port->info->port.tty->driver->num)
875                 return;
876
877         switch (port->info->port.tty->termios->c_line) {
878         case N_IRDA:
879                 val = UART_GET_GCTL(&bfin_serial_ports[line]);
880                 val |= (IREN | RPOLC);
881                 UART_PUT_GCTL(&bfin_serial_ports[line], val);
882                 break;
883         default:
884                 val = UART_GET_GCTL(&bfin_serial_ports[line]);
885                 val &= ~(IREN | RPOLC);
886                 UART_PUT_GCTL(&bfin_serial_ports[line], val);
887         }
888 }
889
890 static struct uart_ops bfin_serial_pops = {
891         .tx_empty       = bfin_serial_tx_empty,
892         .set_mctrl      = bfin_serial_set_mctrl,
893         .get_mctrl      = bfin_serial_get_mctrl,
894         .stop_tx        = bfin_serial_stop_tx,
895         .start_tx       = bfin_serial_start_tx,
896         .stop_rx        = bfin_serial_stop_rx,
897         .enable_ms      = bfin_serial_enable_ms,
898         .break_ctl      = bfin_serial_break_ctl,
899         .startup        = bfin_serial_startup,
900         .shutdown       = bfin_serial_shutdown,
901         .set_termios    = bfin_serial_set_termios,
902         .set_ldisc      = bfin_serial_set_ldisc,
903         .type           = bfin_serial_type,
904         .release_port   = bfin_serial_release_port,
905         .request_port   = bfin_serial_request_port,
906         .config_port    = bfin_serial_config_port,
907         .verify_port    = bfin_serial_verify_port,
908 };
909
910 static void __init bfin_serial_init_ports(void)
911 {
912         static int first = 1;
913         int i;
914
915         if (!first)
916                 return;
917         first = 0;
918
919         for (i = 0; i < nr_active_ports; i++) {
920                 bfin_serial_ports[i].port.uartclk   = get_sclk();
921                 bfin_serial_ports[i].port.fifosize  = BFIN_UART_TX_FIFO_SIZE;
922                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
923                 bfin_serial_ports[i].port.line      = i;
924                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
925                 bfin_serial_ports[i].port.membase   =
926                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
927                 bfin_serial_ports[i].port.mapbase   =
928                         bfin_serial_resource[i].uart_base_addr;
929                 bfin_serial_ports[i].port.irq       =
930                         bfin_serial_resource[i].uart_irq;
931                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
932 #ifdef CONFIG_SERIAL_BFIN_DMA
933                 bfin_serial_ports[i].tx_done        = 1;
934                 bfin_serial_ports[i].tx_count       = 0;
935                 bfin_serial_ports[i].tx_dma_channel =
936                         bfin_serial_resource[i].uart_tx_dma_channel;
937                 bfin_serial_ports[i].rx_dma_channel =
938                         bfin_serial_resource[i].uart_rx_dma_channel;
939                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
940 #endif
941 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
942                 init_timer(&(bfin_serial_ports[i].cts_timer));
943                 bfin_serial_ports[i].cts_pin        =
944                         bfin_serial_resource[i].uart_cts_pin;
945                 bfin_serial_ports[i].rts_pin        =
946                         bfin_serial_resource[i].uart_rts_pin;
947 #endif
948                 bfin_serial_hw_init(&bfin_serial_ports[i]);
949         }
950
951 }
952
953 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
954 /*
955  * If the port was already initialised (eg, by a boot loader),
956  * try to determine the current setup.
957  */
958 static void __init
959 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
960                            int *parity, int *bits)
961 {
962         unsigned short status;
963
964         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
965         if (status == (ERBFI | ETBEI)) {
966                 /* ok, the port was enabled */
967                 u16 lcr, dlh, dll;
968
969                 lcr = UART_GET_LCR(uart);
970
971                 *parity = 'n';
972                 if (lcr & PEN) {
973                         if (lcr & EPS)
974                                 *parity = 'e';
975                         else
976                                 *parity = 'o';
977                 }
978                 switch (lcr & 0x03) {
979                         case 0: *bits = 5; break;
980                         case 1: *bits = 6; break;
981                         case 2: *bits = 7; break;
982                         case 3: *bits = 8; break;
983                 }
984                 /* Set DLAB in LCR to Access DLL and DLH */
985                 UART_SET_DLAB(uart);
986
987                 dll = UART_GET_DLL(uart);
988                 dlh = UART_GET_DLH(uart);
989
990                 /* Clear DLAB in LCR to Access THR RBR IER */
991                 UART_CLEAR_DLAB(uart);
992
993                 *baud = get_sclk() / (16*(dll | dlh << 8));
994         }
995         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __func__, *baud, *parity, *bits);
996 }
997 #endif
998
999 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) || defined(CONFIG_EARLY_PRINTK)
1000 static struct uart_driver bfin_serial_reg;
1001
1002 static int __init
1003 bfin_serial_console_setup(struct console *co, char *options)
1004 {
1005         struct bfin_serial_port *uart;
1006 # ifdef CONFIG_SERIAL_BFIN_CONSOLE
1007         int baud = 57600;
1008         int bits = 8;
1009         int parity = 'n';
1010 #  ifdef CONFIG_SERIAL_BFIN_CTSRTS
1011         int flow = 'r';
1012 #  else
1013         int flow = 'n';
1014 #  endif
1015 # endif
1016
1017         /*
1018          * Check whether an invalid uart number has been specified, and
1019          * if so, search for the first available port that does have
1020          * console support.
1021          */
1022         if (co->index == -1 || co->index >= nr_active_ports)
1023                 co->index = 0;
1024         uart = &bfin_serial_ports[co->index];
1025
1026 # ifdef CONFIG_SERIAL_BFIN_CONSOLE
1027         if (options)
1028                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1029         else
1030                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
1031
1032         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
1033 # else
1034         return 0;
1035 # endif
1036 }
1037 #endif /* defined (CONFIG_SERIAL_BFIN_CONSOLE) ||
1038                                  defined (CONFIG_EARLY_PRINTK) */
1039
1040 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
1041 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
1042 {
1043         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
1044         while (!(UART_GET_LSR(uart) & THRE))
1045                 barrier();
1046         UART_PUT_CHAR(uart, ch);
1047         SSYNC();
1048 }
1049
1050 /*
1051  * Interrupts are disabled on entering
1052  */
1053 static void
1054 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
1055 {
1056         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
1057         int flags = 0;
1058
1059         spin_lock_irqsave(&uart->port.lock, flags);
1060         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
1061         spin_unlock_irqrestore(&uart->port.lock, flags);
1062
1063 }
1064
1065 static struct console bfin_serial_console = {
1066         .name           = BFIN_SERIAL_NAME,
1067         .write          = bfin_serial_console_write,
1068         .device         = uart_console_device,
1069         .setup          = bfin_serial_console_setup,
1070         .flags          = CON_PRINTBUFFER,
1071         .index          = -1,
1072         .data           = &bfin_serial_reg,
1073 };
1074
1075 static int __init bfin_serial_rs_console_init(void)
1076 {
1077         bfin_serial_init_ports();
1078         register_console(&bfin_serial_console);
1079 #ifdef CONFIG_KGDB_UART
1080         kgdb_entry_state = 0;
1081         init_kgdb_uart();
1082 #endif
1083         return 0;
1084 }
1085 console_initcall(bfin_serial_rs_console_init);
1086
1087 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
1088 #else
1089 #define BFIN_SERIAL_CONSOLE     NULL
1090 #endif /* CONFIG_SERIAL_BFIN_CONSOLE */
1091
1092
1093 #ifdef CONFIG_EARLY_PRINTK
1094 static __init void early_serial_putc(struct uart_port *port, int ch)
1095 {
1096         unsigned timeout = 0xffff;
1097         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
1098
1099         while ((!(UART_GET_LSR(uart) & THRE)) && --timeout)
1100                 cpu_relax();
1101         UART_PUT_CHAR(uart, ch);
1102 }
1103
1104 static __init void early_serial_write(struct console *con, const char *s,
1105                                         unsigned int n)
1106 {
1107         struct bfin_serial_port *uart = &bfin_serial_ports[con->index];
1108         unsigned int i;
1109
1110         for (i = 0; i < n; i++, s++) {
1111                 if (*s == '\n')
1112                         early_serial_putc(&uart->port, '\r');
1113                 early_serial_putc(&uart->port, *s);
1114         }
1115 }
1116
1117 static struct __initdata console bfin_early_serial_console = {
1118         .name = "early_BFuart",
1119         .write = early_serial_write,
1120         .device = uart_console_device,
1121         .flags = CON_PRINTBUFFER,
1122         .setup = bfin_serial_console_setup,
1123         .index = -1,
1124         .data  = &bfin_serial_reg,
1125 };
1126
1127 struct console __init *bfin_earlyserial_init(unsigned int port,
1128                                                 unsigned int cflag)
1129 {
1130         struct bfin_serial_port *uart;
1131         struct ktermios t;
1132
1133         if (port == -1 || port >= nr_active_ports)
1134                 port = 0;
1135         bfin_serial_init_ports();
1136         bfin_early_serial_console.index = port;
1137         uart = &bfin_serial_ports[port];
1138         t.c_cflag = cflag;
1139         t.c_iflag = 0;
1140         t.c_oflag = 0;
1141         t.c_lflag = ICANON;
1142         t.c_line = port;
1143         bfin_serial_set_termios(&uart->port, &t, &t);
1144         return &bfin_early_serial_console;
1145 }
1146
1147 #endif /* CONFIG_SERIAL_BFIN_CONSOLE */
1148
1149 static struct uart_driver bfin_serial_reg = {
1150         .owner                  = THIS_MODULE,
1151         .driver_name            = "bfin-uart",
1152         .dev_name               = BFIN_SERIAL_NAME,
1153         .major                  = BFIN_SERIAL_MAJOR,
1154         .minor                  = BFIN_SERIAL_MINOR,
1155         .nr                     = BFIN_UART_NR_PORTS,
1156         .cons                   = BFIN_SERIAL_CONSOLE,
1157 };
1158
1159 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
1160 {
1161         int i;
1162
1163         for (i = 0; i < nr_active_ports; i++) {
1164                 if (bfin_serial_ports[i].port.dev != &dev->dev)
1165                         continue;
1166                 uart_suspend_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1167         }
1168
1169         return 0;
1170 }
1171
1172 static int bfin_serial_resume(struct platform_device *dev)
1173 {
1174         int i;
1175
1176         for (i = 0; i < nr_active_ports; i++) {
1177                 if (bfin_serial_ports[i].port.dev != &dev->dev)
1178                         continue;
1179                 uart_resume_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1180         }
1181
1182         return 0;
1183 }
1184
1185 static int bfin_serial_probe(struct platform_device *dev)
1186 {
1187         struct resource *res = dev->resource;
1188         int i;
1189
1190         for (i = 0; i < dev->num_resources; i++, res++)
1191                 if (res->flags & IORESOURCE_MEM)
1192                         break;
1193
1194         if (i < dev->num_resources) {
1195                 for (i = 0; i < nr_active_ports; i++, res++) {
1196                         if (bfin_serial_ports[i].port.mapbase != res->start)
1197                                 continue;
1198                         bfin_serial_ports[i].port.dev = &dev->dev;
1199                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1200                 }
1201         }
1202
1203         return 0;
1204 }
1205
1206 static int bfin_serial_remove(struct platform_device *dev)
1207 {
1208         int i;
1209
1210         for (i = 0; i < nr_active_ports; i++) {
1211                 if (bfin_serial_ports[i].port.dev != &dev->dev)
1212                         continue;
1213                 uart_remove_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1214                 bfin_serial_ports[i].port.dev = NULL;
1215 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1216                 gpio_free(bfin_serial_ports[i].cts_pin);
1217                 gpio_free(bfin_serial_ports[i].rts_pin);
1218 #endif
1219         }
1220
1221         return 0;
1222 }
1223
1224 static struct platform_driver bfin_serial_driver = {
1225         .probe          = bfin_serial_probe,
1226         .remove         = bfin_serial_remove,
1227         .suspend        = bfin_serial_suspend,
1228         .resume         = bfin_serial_resume,
1229         .driver         = {
1230                 .name   = "bfin-uart",
1231                 .owner  = THIS_MODULE,
1232         },
1233 };
1234
1235 static int __init bfin_serial_init(void)
1236 {
1237         int ret;
1238 #ifdef CONFIG_KGDB_UART
1239         struct bfin_serial_port *uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
1240         struct ktermios t;
1241 #endif
1242
1243         pr_info("Serial: Blackfin serial driver\n");
1244
1245         bfin_serial_init_ports();
1246
1247         ret = uart_register_driver(&bfin_serial_reg);
1248         if (ret == 0) {
1249                 ret = platform_driver_register(&bfin_serial_driver);
1250                 if (ret) {
1251                         pr_debug("uart register failed\n");
1252                         uart_unregister_driver(&bfin_serial_reg);
1253                 }
1254         }
1255 #ifdef CONFIG_KGDB_UART
1256         if (uart->port.cons->index != CONFIG_KGDB_UART_PORT) {
1257                 request_irq(uart->port.irq, bfin_serial_rx_int,
1258                         IRQF_DISABLED, "BFIN_UART_RX", uart);
1259                 pr_info("Request irq for kgdb uart port\n");
1260                 UART_SET_IER(uart, ERBFI);
1261                 SSYNC();
1262                 t.c_cflag = CS8|B57600;
1263                 t.c_iflag = 0;
1264                 t.c_oflag = 0;
1265                 t.c_lflag = ICANON;
1266                 t.c_line = CONFIG_KGDB_UART_PORT;
1267                 bfin_serial_set_termios(&uart->port, &t, &t);
1268         }
1269 #endif
1270         return ret;
1271 }
1272
1273 static void __exit bfin_serial_exit(void)
1274 {
1275         platform_driver_unregister(&bfin_serial_driver);
1276         uart_unregister_driver(&bfin_serial_reg);
1277 }
1278
1279 module_init(bfin_serial_init);
1280 module_exit(bfin_serial_exit);
1281
1282 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1283 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1284 MODULE_LICENSE("GPL");
1285 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);
1286 MODULE_ALIAS("platform:bfin-uart");