Blackfin serial driver: decouple PARODD and CMSPAR checking from PARENB
[safe/jmp/linux-2.6] / drivers / serial / bfin_5xx.c
1 /*
2  * File:         drivers/serial/bfin_5xx.c
3  * Based on:     Based on drivers/serial/sa1100.c
4  * Author:       Aubrey Li <aubrey.li@analog.com>
5  *
6  * Created:
7  * Description:  Driver for blackfin 5xx serial ports
8  *
9  * Modified:
10  *               Copyright 2006 Analog Devices Inc.
11  *
12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program; if not, see the file COPYING, or write
26  * to the Free Software Foundation, Inc.,
27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
28  */
29
30 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
31 #define SUPPORT_SYSRQ
32 #endif
33
34 #include <linux/module.h>
35 #include <linux/ioport.h>
36 #include <linux/init.h>
37 #include <linux/console.h>
38 #include <linux/sysrq.h>
39 #include <linux/platform_device.h>
40 #include <linux/tty.h>
41 #include <linux/tty_flip.h>
42 #include <linux/serial_core.h>
43
44 #include <asm/gpio.h>
45 #include <asm/mach/bfin_serial_5xx.h>
46
47 #ifdef CONFIG_SERIAL_BFIN_DMA
48 #include <linux/dma-mapping.h>
49 #include <asm/io.h>
50 #include <asm/irq.h>
51 #include <asm/cacheflush.h>
52 #endif
53
54 /* UART name and device definitions */
55 #define BFIN_SERIAL_NAME        "ttyBF"
56 #define BFIN_SERIAL_MAJOR       204
57 #define BFIN_SERIAL_MINOR       64
58
59 /*
60  * Setup for console. Argument comes from the menuconfig
61  */
62 #define DMA_RX_XCOUNT           512
63 #define DMA_RX_YCOUNT           (PAGE_SIZE / DMA_RX_XCOUNT)
64
65 #define DMA_RX_FLUSH_JIFFIES    5
66
67 #ifdef CONFIG_SERIAL_BFIN_DMA
68 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
69 #else
70 static void bfin_serial_do_work(struct work_struct *work);
71 static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
72 static void local_put_char(struct bfin_serial_port *uart, char ch);
73 #endif
74
75 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
76
77 /*
78  * interrupts are disabled on entry
79  */
80 static void bfin_serial_stop_tx(struct uart_port *port)
81 {
82         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
83
84 #ifdef CONFIG_SERIAL_BFIN_DMA
85         disable_dma(uart->tx_dma_channel);
86 #else
87         unsigned short ier;
88
89         ier = UART_GET_IER(uart);
90         ier &= ~ETBEI;
91         UART_PUT_IER(uart, ier);
92 #endif
93 }
94
95 /*
96  * port is locked and interrupts are disabled
97  */
98 static void bfin_serial_start_tx(struct uart_port *port)
99 {
100         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
101
102 #ifdef CONFIG_SERIAL_BFIN_DMA
103         bfin_serial_dma_tx_chars(uart);
104 #else
105         unsigned short ier;
106         ier = UART_GET_IER(uart);
107         ier |= ETBEI;
108         UART_PUT_IER(uart, ier);
109         bfin_serial_tx_chars(uart);
110 #endif
111 }
112
113 /*
114  * Interrupts are enabled
115  */
116 static void bfin_serial_stop_rx(struct uart_port *port)
117 {
118         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
119         unsigned short ier;
120
121         ier = UART_GET_IER(uart);
122         ier &= ~ERBFI;
123         UART_PUT_IER(uart, ier);
124 }
125
126 /*
127  * Set the modem control timer to fire immediately.
128  */
129 static void bfin_serial_enable_ms(struct uart_port *port)
130 {
131 }
132
133 #ifdef CONFIG_SERIAL_BFIN_PIO
134 static void local_put_char(struct bfin_serial_port *uart, char ch)
135 {
136         unsigned short status;
137         int flags = 0;
138
139         spin_lock_irqsave(&uart->port.lock, flags);
140
141         do {
142                 status = UART_GET_LSR(uart);
143         } while (!(status & THRE));
144
145         UART_PUT_CHAR(uart, ch);
146         SSYNC();
147
148         spin_unlock_irqrestore(&uart->port.lock, flags);
149 }
150
151 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
152 {
153         struct tty_struct *tty = uart->port.info->tty;
154         unsigned int status, ch, flg;
155 #ifdef BF533_FAMILY
156         static int in_break = 0;
157 #endif
158
159         status = UART_GET_LSR(uart);
160         ch = UART_GET_CHAR(uart);
161         uart->port.icount.rx++;
162
163 #ifdef BF533_FAMILY
164         /* The BF533 family of processors have a nice misbehavior where
165          * they continuously generate characters for a "single" break.
166          * We have to basically ignore this flood until the "next" valid
167          * character comes across.  All other Blackfin families operate
168          * properly though.
169          */
170         if (in_break) {
171                 if (ch != 0) {
172                         in_break = 0;
173                         ch = UART_GET_CHAR(uart);
174                         if (bfin_revid() < 5)
175                                 return;
176                 } else
177                         return;
178         }
179 #endif
180
181         if (status & BI) {
182 #ifdef BF533_FAMILY
183                 in_break = 1;
184 #endif
185                 uart->port.icount.brk++;
186                 if (uart_handle_break(&uart->port))
187                         goto ignore_char;
188                 status &= ~(PE | FE);
189         }
190         if (status & PE)
191                 uart->port.icount.parity++;
192         if (status & OE)
193                 uart->port.icount.overrun++;
194         if (status & FE)
195                 uart->port.icount.frame++;
196
197         status &= uart->port.read_status_mask;
198
199         if (status & BI)
200                 flg = TTY_BREAK;
201         else if (status & PE)
202                 flg = TTY_PARITY;
203         else if (status & FE)
204                 flg = TTY_FRAME;
205         else
206                 flg = TTY_NORMAL;
207
208         if (uart_handle_sysrq_char(&uart->port, ch))
209                 goto ignore_char;
210
211         uart_insert_char(&uart->port, status, OE, ch, flg);
212
213  ignore_char:
214         tty_flip_buffer_push(tty);
215 }
216
217 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
218 {
219         struct circ_buf *xmit = &uart->port.info->xmit;
220
221         if (uart->port.x_char) {
222                 UART_PUT_CHAR(uart, uart->port.x_char);
223                 uart->port.icount.tx++;
224                 uart->port.x_char = 0;
225                 return;
226         }
227         /*
228          * Check the modem control lines before
229          * transmitting anything.
230          */
231         bfin_serial_mctrl_check(uart);
232
233         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
234                 bfin_serial_stop_tx(&uart->port);
235                 return;
236         }
237
238         local_put_char(uart, xmit->buf[xmit->tail]);
239         xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
240         uart->port.icount.tx++;
241
242         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
243                 uart_write_wakeup(&uart->port);
244
245         if (uart_circ_empty(xmit))
246                 bfin_serial_stop_tx(&uart->port);
247 }
248
249 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
250 {
251         struct bfin_serial_port *uart = dev_id;
252
253         spin_lock(&uart->port.lock);
254         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_RX_READY)
255                 bfin_serial_rx_chars(uart);
256         spin_unlock(&uart->port.lock);
257         return IRQ_HANDLED;
258 }
259
260 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
261 {
262         struct bfin_serial_port *uart = dev_id;
263
264         spin_lock(&uart->port.lock);
265         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_TX_READY)
266                 bfin_serial_tx_chars(uart);
267         spin_unlock(&uart->port.lock);
268         return IRQ_HANDLED;
269 }
270
271
272 static void bfin_serial_do_work(struct work_struct *work)
273 {
274         struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
275
276         bfin_serial_mctrl_check(uart);
277 }
278
279 #endif
280
281 #ifdef CONFIG_SERIAL_BFIN_DMA
282 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
283 {
284         struct circ_buf *xmit = &uart->port.info->xmit;
285         unsigned short ier;
286         int flags = 0;
287
288         if (!uart->tx_done)
289                 return;
290
291         uart->tx_done = 0;
292
293         if (uart->port.x_char) {
294                 UART_PUT_CHAR(uart, uart->port.x_char);
295                 uart->port.icount.tx++;
296                 uart->port.x_char = 0;
297                 uart->tx_done = 1;
298                 return;
299         }
300         /*
301          * Check the modem control lines before
302          * transmitting anything.
303          */
304         bfin_serial_mctrl_check(uart);
305
306         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
307                 bfin_serial_stop_tx(&uart->port);
308                 uart->tx_done = 1;
309                 return;
310         }
311
312         spin_lock_irqsave(&uart->port.lock, flags);
313         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
314         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
315                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
316         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
317                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
318         set_dma_config(uart->tx_dma_channel,
319                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
320                         INTR_ON_BUF,
321                         DIMENSION_LINEAR,
322                         DATA_SIZE_8));
323         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
324         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
325         set_dma_x_modify(uart->tx_dma_channel, 1);
326         enable_dma(uart->tx_dma_channel);
327         ier = UART_GET_IER(uart);
328         ier |= ETBEI;
329         UART_PUT_IER(uart, ier);
330         spin_unlock_irqrestore(&uart->port.lock, flags);
331 }
332
333 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
334 {
335         struct tty_struct *tty = uart->port.info->tty;
336         int i, flg, status;
337
338         status = UART_GET_LSR(uart);
339         uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
340
341         if (status & BI) {
342                 uart->port.icount.brk++;
343                 if (uart_handle_break(&uart->port))
344                         goto dma_ignore_char;
345                 status &= ~(PE | FE);
346         }
347         if (status & PE)
348                 uart->port.icount.parity++;
349         if (status & OE)
350                 uart->port.icount.overrun++;
351         if (status & FE)
352                 uart->port.icount.frame++;
353
354         status &= uart->port.read_status_mask;
355
356         if (status & BI)
357                 flg = TTY_BREAK;
358         else if (status & PE)
359                 flg = TTY_PARITY;
360         else if (status & FE)
361                 flg = TTY_FRAME;
362         else
363                 flg = TTY_NORMAL;
364
365         for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) {
366                 if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
367                         goto dma_ignore_char;
368                 uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg);
369         }
370
371  dma_ignore_char:
372         tty_flip_buffer_push(tty);
373 }
374
375 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
376 {
377         int x_pos, pos;
378         int flags = 0;
379
380         bfin_serial_dma_tx_chars(uart);
381
382         spin_lock_irqsave(&uart->port.lock, flags);
383         x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel);
384         if (x_pos == DMA_RX_XCOUNT)
385                 x_pos = 0;
386
387         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
388
389         if (pos>uart->rx_dma_buf.tail) {
390                 uart->rx_dma_buf.tail = pos;
391                 bfin_serial_dma_rx_chars(uart);
392                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
393         }
394         spin_unlock_irqrestore(&uart->port.lock, flags);
395         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
396         add_timer(&(uart->rx_dma_timer));
397 }
398
399 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
400 {
401         struct bfin_serial_port *uart = dev_id;
402         struct circ_buf *xmit = &uart->port.info->xmit;
403         unsigned short ier;
404
405         spin_lock(&uart->port.lock);
406         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
407                 clear_dma_irqstat(uart->tx_dma_channel);
408                 disable_dma(uart->tx_dma_channel);
409                 ier = UART_GET_IER(uart);
410                 ier &= ~ETBEI;
411                 UART_PUT_IER(uart, ier);
412                 xmit->tail = (xmit->tail+uart->tx_count) &(UART_XMIT_SIZE -1);
413                 uart->port.icount.tx+=uart->tx_count;
414
415                 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
416                         uart_write_wakeup(&uart->port);
417
418                 if (uart_circ_empty(xmit))
419                         bfin_serial_stop_tx(&uart->port);
420                 uart->tx_done = 1;
421         }
422
423         spin_unlock(&uart->port.lock);
424         return IRQ_HANDLED;
425 }
426
427 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
428 {
429         struct bfin_serial_port *uart = dev_id;
430         unsigned short irqstat;
431
432         uart->rx_dma_nrows++;
433         if (uart->rx_dma_nrows == DMA_RX_YCOUNT) {
434                 uart->rx_dma_nrows = 0;
435                 uart->rx_dma_buf.tail = DMA_RX_XCOUNT*DMA_RX_YCOUNT;
436                 bfin_serial_dma_rx_chars(uart);
437                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail = 0;
438         }
439         spin_lock(&uart->port.lock);
440         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
441         clear_dma_irqstat(uart->rx_dma_channel);
442
443         spin_unlock(&uart->port.lock);
444         return IRQ_HANDLED;
445 }
446 #endif
447
448 /*
449  * Return TIOCSER_TEMT when transmitter is not busy.
450  */
451 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
452 {
453         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
454         unsigned short lsr;
455
456         lsr = UART_GET_LSR(uart);
457         if (lsr & TEMT)
458                 return TIOCSER_TEMT;
459         else
460                 return 0;
461 }
462
463 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
464 {
465 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
466         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
467         if (uart->cts_pin < 0)
468                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
469
470         if (gpio_get_value(uart->cts_pin))
471                 return TIOCM_DSR | TIOCM_CAR;
472         else
473 #endif
474                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
475 }
476
477 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
478 {
479 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
480         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
481         if (uart->rts_pin < 0)
482                 return;
483
484         if (mctrl & TIOCM_RTS)
485                 gpio_set_value(uart->rts_pin, 0);
486         else
487                 gpio_set_value(uart->rts_pin, 1);
488 #endif
489 }
490
491 /*
492  * Handle any change of modem status signal since we were last called.
493  */
494 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
495 {
496 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
497         unsigned int status;
498 # ifdef CONFIG_SERIAL_BFIN_DMA
499         struct uart_info *info = uart->port.info;
500         struct tty_struct *tty = info->tty;
501
502         status = bfin_serial_get_mctrl(&uart->port);
503         if (!(status & TIOCM_CTS)) {
504                 tty->hw_stopped = 1;
505         } else {
506                 tty->hw_stopped = 0;
507         }
508 # else
509         status = bfin_serial_get_mctrl(&uart->port);
510         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
511         if (!(status & TIOCM_CTS))
512                 schedule_work(&uart->cts_workqueue);
513 # endif
514 #endif
515 }
516
517 /*
518  * Interrupts are always disabled.
519  */
520 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
521 {
522         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
523         u16 lcr = UART_GET_LCR(uart);
524         if (break_state)
525                 lcr |= SB;
526         else
527                 lcr &= ~SB;
528         UART_PUT_LCR(uart, lcr);
529         SSYNC();
530 }
531
532 static int bfin_serial_startup(struct uart_port *port)
533 {
534         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
535
536 #ifdef CONFIG_SERIAL_BFIN_DMA
537         dma_addr_t dma_handle;
538
539         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
540                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
541                 return -EBUSY;
542         }
543
544         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
545                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
546                 free_dma(uart->rx_dma_channel);
547                 return -EBUSY;
548         }
549
550         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
551         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
552
553         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
554         uart->rx_dma_buf.head = 0;
555         uart->rx_dma_buf.tail = 0;
556         uart->rx_dma_nrows = 0;
557
558         set_dma_config(uart->rx_dma_channel,
559                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
560                                 INTR_ON_ROW, DIMENSION_2D,
561                                 DATA_SIZE_8));
562         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
563         set_dma_x_modify(uart->rx_dma_channel, 1);
564         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
565         set_dma_y_modify(uart->rx_dma_channel, 1);
566         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
567         enable_dma(uart->rx_dma_channel);
568
569         uart->rx_dma_timer.data = (unsigned long)(uart);
570         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
571         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
572         add_timer(&(uart->rx_dma_timer));
573 #else
574         if (request_irq
575             (uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
576              "BFIN_UART_RX", uart)) {
577                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
578                 return -EBUSY;
579         }
580
581         if (request_irq
582             (uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
583              "BFIN_UART_TX", uart)) {
584                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
585                 free_irq(uart->port.irq, uart);
586                 return -EBUSY;
587         }
588 #endif
589         UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
590         return 0;
591 }
592
593 static void bfin_serial_shutdown(struct uart_port *port)
594 {
595         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
596
597 #ifdef CONFIG_SERIAL_BFIN_DMA
598         disable_dma(uart->tx_dma_channel);
599         free_dma(uart->tx_dma_channel);
600         disable_dma(uart->rx_dma_channel);
601         free_dma(uart->rx_dma_channel);
602         del_timer(&(uart->rx_dma_timer));
603 #else
604         free_irq(uart->port.irq, uart);
605         free_irq(uart->port.irq+1, uart);
606 #endif
607 }
608
609 static void
610 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
611                    struct ktermios *old)
612 {
613         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
614         unsigned long flags;
615         unsigned int baud, quot;
616         unsigned short val, ier, lsr, lcr = 0;
617
618         switch (termios->c_cflag & CSIZE) {
619         case CS8:
620                 lcr = WLS(8);
621                 break;
622         case CS7:
623                 lcr = WLS(7);
624                 break;
625         case CS6:
626                 lcr = WLS(6);
627                 break;
628         case CS5:
629                 lcr = WLS(5);
630                 break;
631         default:
632                 printk(KERN_ERR "%s: word lengh not supported\n",
633                         __FUNCTION__);
634         }
635
636         if (termios->c_cflag & CSTOPB)
637                 lcr |= STB;
638         if (termios->c_cflag & PARENB)
639                 lcr |= PEN;
640         if (!(termios->c_cflag & PARODD))
641                 lcr |= EPS;
642         if (termios->c_cflag & CMSPAR)
643                 lcr |= STP;
644
645         port->read_status_mask = OE;
646         if (termios->c_iflag & INPCK)
647                 port->read_status_mask |= (FE | PE);
648         if (termios->c_iflag & (BRKINT | PARMRK))
649                 port->read_status_mask |= BI;
650
651         /*
652          * Characters to ignore
653          */
654         port->ignore_status_mask = 0;
655         if (termios->c_iflag & IGNPAR)
656                 port->ignore_status_mask |= FE | PE;
657         if (termios->c_iflag & IGNBRK) {
658                 port->ignore_status_mask |= BI;
659                 /*
660                  * If we're ignoring parity and break indicators,
661                  * ignore overruns too (for real raw support).
662                  */
663                 if (termios->c_iflag & IGNPAR)
664                         port->ignore_status_mask |= OE;
665         }
666
667         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
668         quot = uart_get_divisor(port, baud);
669         spin_lock_irqsave(&uart->port.lock, flags);
670
671         do {
672                 lsr = UART_GET_LSR(uart);
673         } while (!(lsr & TEMT));
674
675         /* Disable UART */
676         ier = UART_GET_IER(uart);
677         UART_PUT_IER(uart, 0);
678
679         /* Set DLAB in LCR to Access DLL and DLH */
680         val = UART_GET_LCR(uart);
681         val |= DLAB;
682         UART_PUT_LCR(uart, val);
683         SSYNC();
684
685         UART_PUT_DLL(uart, quot & 0xFF);
686         SSYNC();
687         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
688         SSYNC();
689
690         /* Clear DLAB in LCR to Access THR RBR IER */
691         val = UART_GET_LCR(uart);
692         val &= ~DLAB;
693         UART_PUT_LCR(uart, val);
694         SSYNC();
695
696         UART_PUT_LCR(uart, lcr);
697
698         /* Enable UART */
699         UART_PUT_IER(uart, ier);
700
701         val = UART_GET_GCTL(uart);
702         val |= UCEN;
703         UART_PUT_GCTL(uart, val);
704
705         spin_unlock_irqrestore(&uart->port.lock, flags);
706 }
707
708 static const char *bfin_serial_type(struct uart_port *port)
709 {
710         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
711
712         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
713 }
714
715 /*
716  * Release the memory region(s) being used by 'port'.
717  */
718 static void bfin_serial_release_port(struct uart_port *port)
719 {
720 }
721
722 /*
723  * Request the memory region(s) being used by 'port'.
724  */
725 static int bfin_serial_request_port(struct uart_port *port)
726 {
727         return 0;
728 }
729
730 /*
731  * Configure/autoconfigure the port.
732  */
733 static void bfin_serial_config_port(struct uart_port *port, int flags)
734 {
735         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
736
737         if (flags & UART_CONFIG_TYPE &&
738             bfin_serial_request_port(&uart->port) == 0)
739                 uart->port.type = PORT_BFIN;
740 }
741
742 /*
743  * Verify the new serial_struct (for TIOCSSERIAL).
744  * The only change we allow are to the flags and type, and
745  * even then only between PORT_BFIN and PORT_UNKNOWN
746  */
747 static int
748 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
749 {
750         return 0;
751 }
752
753 static struct uart_ops bfin_serial_pops = {
754         .tx_empty       = bfin_serial_tx_empty,
755         .set_mctrl      = bfin_serial_set_mctrl,
756         .get_mctrl      = bfin_serial_get_mctrl,
757         .stop_tx        = bfin_serial_stop_tx,
758         .start_tx       = bfin_serial_start_tx,
759         .stop_rx        = bfin_serial_stop_rx,
760         .enable_ms      = bfin_serial_enable_ms,
761         .break_ctl      = bfin_serial_break_ctl,
762         .startup        = bfin_serial_startup,
763         .shutdown       = bfin_serial_shutdown,
764         .set_termios    = bfin_serial_set_termios,
765         .type           = bfin_serial_type,
766         .release_port   = bfin_serial_release_port,
767         .request_port   = bfin_serial_request_port,
768         .config_port    = bfin_serial_config_port,
769         .verify_port    = bfin_serial_verify_port,
770 };
771
772 static void __init bfin_serial_init_ports(void)
773 {
774         static int first = 1;
775         int i;
776
777         if (!first)
778                 return;
779         first = 0;
780
781         for (i = 0; i < nr_ports; i++) {
782                 bfin_serial_ports[i].port.uartclk   = get_sclk();
783                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
784                 bfin_serial_ports[i].port.line      = i;
785                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
786                 bfin_serial_ports[i].port.membase   =
787                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
788                 bfin_serial_ports[i].port.mapbase   =
789                         bfin_serial_resource[i].uart_base_addr;
790                 bfin_serial_ports[i].port.irq       =
791                         bfin_serial_resource[i].uart_irq;
792                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
793 #ifdef CONFIG_SERIAL_BFIN_DMA
794                 bfin_serial_ports[i].tx_done        = 1;
795                 bfin_serial_ports[i].tx_count       = 0;
796                 bfin_serial_ports[i].tx_dma_channel =
797                         bfin_serial_resource[i].uart_tx_dma_channel;
798                 bfin_serial_ports[i].rx_dma_channel =
799                         bfin_serial_resource[i].uart_rx_dma_channel;
800                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
801 #else
802                 INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
803 #endif
804 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
805                 bfin_serial_ports[i].cts_pin        =
806                         bfin_serial_resource[i].uart_cts_pin;
807                 bfin_serial_ports[i].rts_pin        =
808                         bfin_serial_resource[i].uart_rts_pin;
809 #endif
810                 bfin_serial_hw_init(&bfin_serial_ports[i]);
811
812         }
813 }
814
815 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
816 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
817 {
818         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
819         while (!(UART_GET_LSR(uart)))
820                 barrier();
821         UART_PUT_CHAR(uart, ch);
822         SSYNC();
823 }
824
825 /*
826  * Interrupts are disabled on entering
827  */
828 static void
829 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
830 {
831         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
832         int flags = 0;
833
834         spin_lock_irqsave(&uart->port.lock, flags);
835         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
836         spin_unlock_irqrestore(&uart->port.lock, flags);
837
838 }
839
840 /*
841  * If the port was already initialised (eg, by a boot loader),
842  * try to determine the current setup.
843  */
844 static void __init
845 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
846                            int *parity, int *bits)
847 {
848         unsigned short status;
849
850         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
851         if (status == (ERBFI | ETBEI)) {
852                 /* ok, the port was enabled */
853                 unsigned short lcr, val;
854                 unsigned short dlh, dll;
855
856                 lcr = UART_GET_LCR(uart);
857
858                 *parity = 'n';
859                 if (lcr & PEN) {
860                         if (lcr & EPS)
861                                 *parity = 'e';
862                         else
863                                 *parity = 'o';
864                 }
865                 switch (lcr & 0x03) {
866                         case 0: *bits = 5; break;
867                         case 1: *bits = 6; break;
868                         case 2: *bits = 7; break;
869                         case 3: *bits = 8; break;
870                 }
871                 /* Set DLAB in LCR to Access DLL and DLH */
872                 val = UART_GET_LCR(uart);
873                 val |= DLAB;
874                 UART_PUT_LCR(uart, val);
875
876                 dll = UART_GET_DLL(uart);
877                 dlh = UART_GET_DLH(uart);
878
879                 /* Clear DLAB in LCR to Access THR RBR IER */
880                 val = UART_GET_LCR(uart);
881                 val &= ~DLAB;
882                 UART_PUT_LCR(uart, val);
883
884                 *baud = get_sclk() / (16*(dll | dlh << 8));
885         }
886         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
887 }
888
889 static int __init
890 bfin_serial_console_setup(struct console *co, char *options)
891 {
892         struct bfin_serial_port *uart;
893         int baud = 57600;
894         int bits = 8;
895         int parity = 'n';
896 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
897         int flow = 'r';
898 #else
899         int flow = 'n';
900 #endif
901
902         /*
903          * Check whether an invalid uart number has been specified, and
904          * if so, search for the first available port that does have
905          * console support.
906          */
907         if (co->index == -1 || co->index >= nr_ports)
908                 co->index = 0;
909         uart = &bfin_serial_ports[co->index];
910
911         if (options)
912                 uart_parse_options(options, &baud, &parity, &bits, &flow);
913         else
914                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
915
916         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
917 }
918
919 static struct uart_driver bfin_serial_reg;
920 static struct console bfin_serial_console = {
921         .name           = BFIN_SERIAL_NAME,
922         .write          = bfin_serial_console_write,
923         .device         = uart_console_device,
924         .setup          = bfin_serial_console_setup,
925         .flags          = CON_PRINTBUFFER,
926         .index          = -1,
927         .data           = &bfin_serial_reg,
928 };
929
930 static int __init bfin_serial_rs_console_init(void)
931 {
932         bfin_serial_init_ports();
933         register_console(&bfin_serial_console);
934         return 0;
935 }
936 console_initcall(bfin_serial_rs_console_init);
937
938 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
939 #else
940 #define BFIN_SERIAL_CONSOLE     NULL
941 #endif
942
943 static struct uart_driver bfin_serial_reg = {
944         .owner                  = THIS_MODULE,
945         .driver_name            = "bfin-uart",
946         .dev_name               = BFIN_SERIAL_NAME,
947         .major                  = BFIN_SERIAL_MAJOR,
948         .minor                  = BFIN_SERIAL_MINOR,
949         .nr                     = NR_PORTS,
950         .cons                   = BFIN_SERIAL_CONSOLE,
951 };
952
953 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
954 {
955         struct bfin_serial_port *uart = platform_get_drvdata(dev);
956
957         if (uart)
958                 uart_suspend_port(&bfin_serial_reg, &uart->port);
959
960         return 0;
961 }
962
963 static int bfin_serial_resume(struct platform_device *dev)
964 {
965         struct bfin_serial_port *uart = platform_get_drvdata(dev);
966
967         if (uart)
968                 uart_resume_port(&bfin_serial_reg, &uart->port);
969
970         return 0;
971 }
972
973 static int bfin_serial_probe(struct platform_device *dev)
974 {
975         struct resource *res = dev->resource;
976         int i;
977
978         for (i = 0; i < dev->num_resources; i++, res++)
979                 if (res->flags & IORESOURCE_MEM)
980                         break;
981
982         if (i < dev->num_resources) {
983                 for (i = 0; i < nr_ports; i++, res++) {
984                         if (bfin_serial_ports[i].port.mapbase != res->start)
985                                 continue;
986                         bfin_serial_ports[i].port.dev = &dev->dev;
987                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
988                         platform_set_drvdata(dev, &bfin_serial_ports[i]);
989                 }
990         }
991
992         return 0;
993 }
994
995 static int bfin_serial_remove(struct platform_device *pdev)
996 {
997         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
998
999
1000 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1001         gpio_free(uart->cts_pin);
1002         gpio_free(uart->rts_pin);
1003 #endif
1004
1005         platform_set_drvdata(pdev, NULL);
1006
1007         if (uart)
1008                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
1009
1010         return 0;
1011 }
1012
1013 static struct platform_driver bfin_serial_driver = {
1014         .probe          = bfin_serial_probe,
1015         .remove         = bfin_serial_remove,
1016         .suspend        = bfin_serial_suspend,
1017         .resume         = bfin_serial_resume,
1018         .driver         = {
1019                 .name   = "bfin-uart",
1020         },
1021 };
1022
1023 static int __init bfin_serial_init(void)
1024 {
1025         int ret;
1026
1027         pr_info("Serial: Blackfin serial driver\n");
1028
1029         bfin_serial_init_ports();
1030
1031         ret = uart_register_driver(&bfin_serial_reg);
1032         if (ret == 0) {
1033                 ret = platform_driver_register(&bfin_serial_driver);
1034                 if (ret) {
1035                         pr_debug("uart register failed\n");
1036                         uart_unregister_driver(&bfin_serial_reg);
1037                 }
1038         }
1039         return ret;
1040 }
1041
1042 static void __exit bfin_serial_exit(void)
1043 {
1044         platform_driver_unregister(&bfin_serial_driver);
1045         uart_unregister_driver(&bfin_serial_reg);
1046 }
1047
1048 module_init(bfin_serial_init);
1049 module_exit(bfin_serial_exit);
1050
1051 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1052 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1053 MODULE_LICENSE("GPL");
1054 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);