Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
[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         }
189         if (status & PE)
190                 uart->port.icount.parity++;
191         if (status & OE)
192                 uart->port.icount.overrun++;
193         if (status & FE)
194                 uart->port.icount.frame++;
195
196         status &= uart->port.read_status_mask;
197
198         if (status & BI)
199                 flg = TTY_BREAK;
200         else if (status & PE)
201                 flg = TTY_PARITY;
202         else if (status & FE)
203                 flg = TTY_FRAME;
204         else
205                 flg = TTY_NORMAL;
206
207         if (uart_handle_sysrq_char(&uart->port, ch))
208                 goto ignore_char;
209
210         uart_insert_char(&uart->port, status, OE, ch, flg);
211
212  ignore_char:
213         tty_flip_buffer_push(tty);
214 }
215
216 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
217 {
218         struct circ_buf *xmit = &uart->port.info->xmit;
219
220         if (uart->port.x_char) {
221                 UART_PUT_CHAR(uart, uart->port.x_char);
222                 uart->port.icount.tx++;
223                 uart->port.x_char = 0;
224                 return;
225         }
226         /*
227          * Check the modem control lines before
228          * transmitting anything.
229          */
230         bfin_serial_mctrl_check(uart);
231
232         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
233                 bfin_serial_stop_tx(&uart->port);
234                 return;
235         }
236
237         local_put_char(uart, xmit->buf[xmit->tail]);
238         xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
239         uart->port.icount.tx++;
240
241         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
242                 uart_write_wakeup(&uart->port);
243
244         if (uart_circ_empty(xmit))
245                 bfin_serial_stop_tx(&uart->port);
246 }
247
248 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
249 {
250         struct bfin_serial_port *uart = dev_id;
251
252         spin_lock(&uart->port.lock);
253         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_RX_READY)
254                 bfin_serial_rx_chars(uart);
255         spin_unlock(&uart->port.lock);
256         return IRQ_HANDLED;
257 }
258
259 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
260 {
261         struct bfin_serial_port *uart = dev_id;
262
263         spin_lock(&uart->port.lock);
264         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_TX_READY)
265                 bfin_serial_tx_chars(uart);
266         spin_unlock(&uart->port.lock);
267         return IRQ_HANDLED;
268 }
269
270
271 static void bfin_serial_do_work(struct work_struct *work)
272 {
273         struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
274
275         bfin_serial_mctrl_check(uart);
276 }
277
278 #endif
279
280 #ifdef CONFIG_SERIAL_BFIN_DMA
281 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
282 {
283         struct circ_buf *xmit = &uart->port.info->xmit;
284         unsigned short ier;
285         int flags = 0;
286
287         if (!uart->tx_done)
288                 return;
289
290         uart->tx_done = 0;
291
292         if (uart->port.x_char) {
293                 UART_PUT_CHAR(uart, uart->port.x_char);
294                 uart->port.icount.tx++;
295                 uart->port.x_char = 0;
296                 uart->tx_done = 1;
297                 return;
298         }
299         /*
300          * Check the modem control lines before
301          * transmitting anything.
302          */
303         bfin_serial_mctrl_check(uart);
304
305         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
306                 bfin_serial_stop_tx(&uart->port);
307                 uart->tx_done = 1;
308                 return;
309         }
310
311         spin_lock_irqsave(&uart->port.lock, flags);
312         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
313         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
314                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
315         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
316                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
317         set_dma_config(uart->tx_dma_channel,
318                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
319                         INTR_ON_BUF,
320                         DIMENSION_LINEAR,
321                         DATA_SIZE_8));
322         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
323         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
324         set_dma_x_modify(uart->tx_dma_channel, 1);
325         enable_dma(uart->tx_dma_channel);
326         ier = UART_GET_IER(uart);
327         ier |= ETBEI;
328         UART_PUT_IER(uart, ier);
329         spin_unlock_irqrestore(&uart->port.lock, flags);
330 }
331
332 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
333 {
334         struct tty_struct *tty = uart->port.info->tty;
335         int i, flg, status;
336
337         status = UART_GET_LSR(uart);
338         uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
339
340         if (status & BI) {
341                 uart->port.icount.brk++;
342                 if (uart_handle_break(&uart->port))
343                         goto dma_ignore_char;
344         }
345         if (status & PE)
346                 uart->port.icount.parity++;
347         if (status & OE)
348                 uart->port.icount.overrun++;
349         if (status & FE)
350                 uart->port.icount.frame++;
351
352         status &= uart->port.read_status_mask;
353
354         if (status & BI)
355                 flg = TTY_BREAK;
356         else if (status & PE)
357                 flg = TTY_PARITY;
358         else if (status & FE)
359                 flg = TTY_FRAME;
360         else
361                 flg = TTY_NORMAL;
362
363         for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) {
364                 if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
365                         goto dma_ignore_char;
366                 uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg);
367         }
368
369  dma_ignore_char:
370         tty_flip_buffer_push(tty);
371 }
372
373 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
374 {
375         int x_pos, pos;
376         int flags = 0;
377
378         bfin_serial_dma_tx_chars(uart);
379
380         spin_lock_irqsave(&uart->port.lock, flags);
381         x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel);
382         if (x_pos == DMA_RX_XCOUNT)
383                 x_pos = 0;
384
385         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
386
387         if (pos>uart->rx_dma_buf.tail) {
388                 uart->rx_dma_buf.tail = pos;
389                 bfin_serial_dma_rx_chars(uart);
390                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
391         }
392         spin_unlock_irqrestore(&uart->port.lock, flags);
393         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
394         add_timer(&(uart->rx_dma_timer));
395 }
396
397 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
398 {
399         struct bfin_serial_port *uart = dev_id;
400         struct circ_buf *xmit = &uart->port.info->xmit;
401         unsigned short ier;
402
403         spin_lock(&uart->port.lock);
404         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
405                 clear_dma_irqstat(uart->tx_dma_channel);
406                 disable_dma(uart->tx_dma_channel);
407                 ier = UART_GET_IER(uart);
408                 ier &= ~ETBEI;
409                 UART_PUT_IER(uart, ier);
410                 xmit->tail = (xmit->tail+uart->tx_count) &(UART_XMIT_SIZE -1);
411                 uart->port.icount.tx+=uart->tx_count;
412
413                 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
414                         uart_write_wakeup(&uart->port);
415
416                 if (uart_circ_empty(xmit))
417                         bfin_serial_stop_tx(&uart->port);
418                 uart->tx_done = 1;
419         }
420
421         spin_unlock(&uart->port.lock);
422         return IRQ_HANDLED;
423 }
424
425 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
426 {
427         struct bfin_serial_port *uart = dev_id;
428         unsigned short irqstat;
429
430         uart->rx_dma_nrows++;
431         if (uart->rx_dma_nrows == DMA_RX_YCOUNT) {
432                 uart->rx_dma_nrows = 0;
433                 uart->rx_dma_buf.tail = DMA_RX_XCOUNT*DMA_RX_YCOUNT;
434                 bfin_serial_dma_rx_chars(uart);
435                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail = 0;
436         }
437         spin_lock(&uart->port.lock);
438         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
439         clear_dma_irqstat(uart->rx_dma_channel);
440
441         spin_unlock(&uart->port.lock);
442         return IRQ_HANDLED;
443 }
444 #endif
445
446 /*
447  * Return TIOCSER_TEMT when transmitter is not busy.
448  */
449 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
450 {
451         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
452         unsigned short lsr;
453
454         lsr = UART_GET_LSR(uart);
455         if (lsr & TEMT)
456                 return TIOCSER_TEMT;
457         else
458                 return 0;
459 }
460
461 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
462 {
463 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
464         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
465         if (uart->cts_pin < 0)
466                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
467
468         if (gpio_get_value(uart->cts_pin))
469                 return TIOCM_DSR | TIOCM_CAR;
470         else
471 #endif
472                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
473 }
474
475 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
476 {
477 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
478         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
479         if (uart->rts_pin < 0)
480                 return;
481
482         if (mctrl & TIOCM_RTS)
483                 gpio_set_value(uart->rts_pin, 0);
484         else
485                 gpio_set_value(uart->rts_pin, 1);
486 #endif
487 }
488
489 /*
490  * Handle any change of modem status signal since we were last called.
491  */
492 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
493 {
494 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
495         unsigned int status;
496 # ifdef CONFIG_SERIAL_BFIN_DMA
497         struct uart_info *info = uart->port.info;
498         struct tty_struct *tty = info->tty;
499
500         status = bfin_serial_get_mctrl(&uart->port);
501         if (!(status & TIOCM_CTS)) {
502                 tty->hw_stopped = 1;
503         } else {
504                 tty->hw_stopped = 0;
505         }
506 # else
507         status = bfin_serial_get_mctrl(&uart->port);
508         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
509         if (!(status & TIOCM_CTS))
510                 schedule_work(&uart->cts_workqueue);
511 # endif
512 #endif
513 }
514
515 /*
516  * Interrupts are always disabled.
517  */
518 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
519 {
520 }
521
522 static int bfin_serial_startup(struct uart_port *port)
523 {
524         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
525
526 #ifdef CONFIG_SERIAL_BFIN_DMA
527         dma_addr_t dma_handle;
528
529         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
530                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
531                 return -EBUSY;
532         }
533
534         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
535                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
536                 free_dma(uart->rx_dma_channel);
537                 return -EBUSY;
538         }
539
540         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
541         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
542
543         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
544         uart->rx_dma_buf.head = 0;
545         uart->rx_dma_buf.tail = 0;
546         uart->rx_dma_nrows = 0;
547
548         set_dma_config(uart->rx_dma_channel,
549                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
550                                 INTR_ON_ROW, DIMENSION_2D,
551                                 DATA_SIZE_8));
552         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
553         set_dma_x_modify(uart->rx_dma_channel, 1);
554         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
555         set_dma_y_modify(uart->rx_dma_channel, 1);
556         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
557         enable_dma(uart->rx_dma_channel);
558
559         uart->rx_dma_timer.data = (unsigned long)(uart);
560         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
561         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
562         add_timer(&(uart->rx_dma_timer));
563 #else
564         if (request_irq
565             (uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
566              "BFIN_UART_RX", uart)) {
567                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
568                 return -EBUSY;
569         }
570
571         if (request_irq
572             (uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
573              "BFIN_UART_TX", uart)) {
574                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
575                 free_irq(uart->port.irq, uart);
576                 return -EBUSY;
577         }
578 #endif
579         UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
580         return 0;
581 }
582
583 static void bfin_serial_shutdown(struct uart_port *port)
584 {
585         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
586
587 #ifdef CONFIG_SERIAL_BFIN_DMA
588         disable_dma(uart->tx_dma_channel);
589         free_dma(uart->tx_dma_channel);
590         disable_dma(uart->rx_dma_channel);
591         free_dma(uart->rx_dma_channel);
592         del_timer(&(uart->rx_dma_timer));
593 #else
594         free_irq(uart->port.irq, uart);
595         free_irq(uart->port.irq+1, uart);
596 #endif
597 }
598
599 static void
600 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
601                    struct ktermios *old)
602 {
603         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
604         unsigned long flags;
605         unsigned int baud, quot;
606         unsigned short val, ier, lsr, lcr = 0;
607
608         switch (termios->c_cflag & CSIZE) {
609         case CS8:
610                 lcr = WLS(8);
611                 break;
612         case CS7:
613                 lcr = WLS(7);
614                 break;
615         case CS6:
616                 lcr = WLS(6);
617                 break;
618         case CS5:
619                 lcr = WLS(5);
620                 break;
621         default:
622                 printk(KERN_ERR "%s: word lengh not supported\n",
623                         __FUNCTION__);
624         }
625
626         if (termios->c_cflag & CSTOPB)
627                 lcr |= STB;
628         if (termios->c_cflag & PARENB) {
629                 lcr |= PEN;
630                 if (!(termios->c_cflag & PARODD))
631                         lcr |= EPS;
632         }
633
634         port->read_status_mask = OE;
635         if (termios->c_iflag & INPCK)
636                 port->read_status_mask |= (FE | PE);
637         if (termios->c_iflag & (BRKINT | PARMRK))
638                 port->read_status_mask |= BI;
639
640         /*
641          * Characters to ignore
642          */
643         port->ignore_status_mask = 0;
644         if (termios->c_iflag & IGNPAR)
645                 port->ignore_status_mask |= FE | PE;
646         if (termios->c_iflag & IGNBRK) {
647                 port->ignore_status_mask |= BI;
648                 /*
649                  * If we're ignoring parity and break indicators,
650                  * ignore overruns too (for real raw support).
651                  */
652                 if (termios->c_iflag & IGNPAR)
653                         port->ignore_status_mask |= OE;
654         }
655
656         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
657         quot = uart_get_divisor(port, baud);
658         spin_lock_irqsave(&uart->port.lock, flags);
659
660         do {
661                 lsr = UART_GET_LSR(uart);
662         } while (!(lsr & TEMT));
663
664         /* Disable UART */
665         ier = UART_GET_IER(uart);
666         UART_PUT_IER(uart, 0);
667
668         /* Set DLAB in LCR to Access DLL and DLH */
669         val = UART_GET_LCR(uart);
670         val |= DLAB;
671         UART_PUT_LCR(uart, val);
672         SSYNC();
673
674         UART_PUT_DLL(uart, quot & 0xFF);
675         SSYNC();
676         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
677         SSYNC();
678
679         /* Clear DLAB in LCR to Access THR RBR IER */
680         val = UART_GET_LCR(uart);
681         val &= ~DLAB;
682         UART_PUT_LCR(uart, val);
683         SSYNC();
684
685         UART_PUT_LCR(uart, lcr);
686
687         /* Enable UART */
688         UART_PUT_IER(uart, ier);
689
690         val = UART_GET_GCTL(uart);
691         val |= UCEN;
692         UART_PUT_GCTL(uart, val);
693
694         spin_unlock_irqrestore(&uart->port.lock, flags);
695 }
696
697 static const char *bfin_serial_type(struct uart_port *port)
698 {
699         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
700
701         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
702 }
703
704 /*
705  * Release the memory region(s) being used by 'port'.
706  */
707 static void bfin_serial_release_port(struct uart_port *port)
708 {
709 }
710
711 /*
712  * Request the memory region(s) being used by 'port'.
713  */
714 static int bfin_serial_request_port(struct uart_port *port)
715 {
716         return 0;
717 }
718
719 /*
720  * Configure/autoconfigure the port.
721  */
722 static void bfin_serial_config_port(struct uart_port *port, int flags)
723 {
724         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
725
726         if (flags & UART_CONFIG_TYPE &&
727             bfin_serial_request_port(&uart->port) == 0)
728                 uart->port.type = PORT_BFIN;
729 }
730
731 /*
732  * Verify the new serial_struct (for TIOCSSERIAL).
733  * The only change we allow are to the flags and type, and
734  * even then only between PORT_BFIN and PORT_UNKNOWN
735  */
736 static int
737 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
738 {
739         return 0;
740 }
741
742 static struct uart_ops bfin_serial_pops = {
743         .tx_empty       = bfin_serial_tx_empty,
744         .set_mctrl      = bfin_serial_set_mctrl,
745         .get_mctrl      = bfin_serial_get_mctrl,
746         .stop_tx        = bfin_serial_stop_tx,
747         .start_tx       = bfin_serial_start_tx,
748         .stop_rx        = bfin_serial_stop_rx,
749         .enable_ms      = bfin_serial_enable_ms,
750         .break_ctl      = bfin_serial_break_ctl,
751         .startup        = bfin_serial_startup,
752         .shutdown       = bfin_serial_shutdown,
753         .set_termios    = bfin_serial_set_termios,
754         .type           = bfin_serial_type,
755         .release_port   = bfin_serial_release_port,
756         .request_port   = bfin_serial_request_port,
757         .config_port    = bfin_serial_config_port,
758         .verify_port    = bfin_serial_verify_port,
759 };
760
761 static void __init bfin_serial_init_ports(void)
762 {
763         static int first = 1;
764         int i;
765
766         if (!first)
767                 return;
768         first = 0;
769
770         for (i = 0; i < nr_ports; i++) {
771                 bfin_serial_ports[i].port.uartclk   = get_sclk();
772                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
773                 bfin_serial_ports[i].port.line      = i;
774                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
775                 bfin_serial_ports[i].port.membase   =
776                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
777                 bfin_serial_ports[i].port.mapbase   =
778                         bfin_serial_resource[i].uart_base_addr;
779                 bfin_serial_ports[i].port.irq       =
780                         bfin_serial_resource[i].uart_irq;
781                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
782 #ifdef CONFIG_SERIAL_BFIN_DMA
783                 bfin_serial_ports[i].tx_done        = 1;
784                 bfin_serial_ports[i].tx_count       = 0;
785                 bfin_serial_ports[i].tx_dma_channel =
786                         bfin_serial_resource[i].uart_tx_dma_channel;
787                 bfin_serial_ports[i].rx_dma_channel =
788                         bfin_serial_resource[i].uart_rx_dma_channel;
789                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
790 #else
791                 INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
792 #endif
793 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
794                 bfin_serial_ports[i].cts_pin        =
795                         bfin_serial_resource[i].uart_cts_pin;
796                 bfin_serial_ports[i].rts_pin        =
797                         bfin_serial_resource[i].uart_rts_pin;
798 #endif
799                 bfin_serial_hw_init(&bfin_serial_ports[i]);
800
801         }
802 }
803
804 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
805 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
806 {
807         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
808         while (!(UART_GET_LSR(uart)))
809                 barrier();
810         UART_PUT_CHAR(uart, ch);
811         SSYNC();
812 }
813
814 /*
815  * Interrupts are disabled on entering
816  */
817 static void
818 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
819 {
820         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
821         int flags = 0;
822
823         spin_lock_irqsave(&uart->port.lock, flags);
824         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
825         spin_unlock_irqrestore(&uart->port.lock, flags);
826
827 }
828
829 /*
830  * If the port was already initialised (eg, by a boot loader),
831  * try to determine the current setup.
832  */
833 static void __init
834 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
835                            int *parity, int *bits)
836 {
837         unsigned short status;
838
839         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
840         if (status == (ERBFI | ETBEI)) {
841                 /* ok, the port was enabled */
842                 unsigned short lcr, val;
843                 unsigned short dlh, dll;
844
845                 lcr = UART_GET_LCR(uart);
846
847                 *parity = 'n';
848                 if (lcr & PEN) {
849                         if (lcr & EPS)
850                                 *parity = 'e';
851                         else
852                                 *parity = 'o';
853                 }
854                 switch (lcr & 0x03) {
855                         case 0: *bits = 5; break;
856                         case 1: *bits = 6; break;
857                         case 2: *bits = 7; break;
858                         case 3: *bits = 8; break;
859                 }
860                 /* Set DLAB in LCR to Access DLL and DLH */
861                 val = UART_GET_LCR(uart);
862                 val |= DLAB;
863                 UART_PUT_LCR(uart, val);
864
865                 dll = UART_GET_DLL(uart);
866                 dlh = UART_GET_DLH(uart);
867
868                 /* Clear DLAB in LCR to Access THR RBR IER */
869                 val = UART_GET_LCR(uart);
870                 val &= ~DLAB;
871                 UART_PUT_LCR(uart, val);
872
873                 *baud = get_sclk() / (16*(dll | dlh << 8));
874         }
875         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
876 }
877
878 static int __init
879 bfin_serial_console_setup(struct console *co, char *options)
880 {
881         struct bfin_serial_port *uart;
882         int baud = 57600;
883         int bits = 8;
884         int parity = 'n';
885 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
886         int flow = 'r';
887 #else
888         int flow = 'n';
889 #endif
890
891         /*
892          * Check whether an invalid uart number has been specified, and
893          * if so, search for the first available port that does have
894          * console support.
895          */
896         if (co->index == -1 || co->index >= nr_ports)
897                 co->index = 0;
898         uart = &bfin_serial_ports[co->index];
899
900         if (options)
901                 uart_parse_options(options, &baud, &parity, &bits, &flow);
902         else
903                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
904
905         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
906 }
907
908 static struct uart_driver bfin_serial_reg;
909 static struct console bfin_serial_console = {
910         .name           = BFIN_SERIAL_NAME,
911         .write          = bfin_serial_console_write,
912         .device         = uart_console_device,
913         .setup          = bfin_serial_console_setup,
914         .flags          = CON_PRINTBUFFER,
915         .index          = -1,
916         .data           = &bfin_serial_reg,
917 };
918
919 static int __init bfin_serial_rs_console_init(void)
920 {
921         bfin_serial_init_ports();
922         register_console(&bfin_serial_console);
923         return 0;
924 }
925 console_initcall(bfin_serial_rs_console_init);
926
927 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
928 #else
929 #define BFIN_SERIAL_CONSOLE     NULL
930 #endif
931
932 static struct uart_driver bfin_serial_reg = {
933         .owner                  = THIS_MODULE,
934         .driver_name            = "bfin-uart",
935         .dev_name               = BFIN_SERIAL_NAME,
936         .major                  = BFIN_SERIAL_MAJOR,
937         .minor                  = BFIN_SERIAL_MINOR,
938         .nr                     = NR_PORTS,
939         .cons                   = BFIN_SERIAL_CONSOLE,
940 };
941
942 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
943 {
944         struct bfin_serial_port *uart = platform_get_drvdata(dev);
945
946         if (uart)
947                 uart_suspend_port(&bfin_serial_reg, &uart->port);
948
949         return 0;
950 }
951
952 static int bfin_serial_resume(struct platform_device *dev)
953 {
954         struct bfin_serial_port *uart = platform_get_drvdata(dev);
955
956         if (uart)
957                 uart_resume_port(&bfin_serial_reg, &uart->port);
958
959         return 0;
960 }
961
962 static int bfin_serial_probe(struct platform_device *dev)
963 {
964         struct resource *res = dev->resource;
965         int i;
966
967         for (i = 0; i < dev->num_resources; i++, res++)
968                 if (res->flags & IORESOURCE_MEM)
969                         break;
970
971         if (i < dev->num_resources) {
972                 for (i = 0; i < nr_ports; i++, res++) {
973                         if (bfin_serial_ports[i].port.mapbase != res->start)
974                                 continue;
975                         bfin_serial_ports[i].port.dev = &dev->dev;
976                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
977                         platform_set_drvdata(dev, &bfin_serial_ports[i]);
978                 }
979         }
980
981         return 0;
982 }
983
984 static int bfin_serial_remove(struct platform_device *pdev)
985 {
986         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
987
988
989 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
990         gpio_free(uart->cts_pin);
991         gpio_free(uart->rts_pin);
992 #endif
993
994         platform_set_drvdata(pdev, NULL);
995
996         if (uart)
997                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
998
999         return 0;
1000 }
1001
1002 static struct platform_driver bfin_serial_driver = {
1003         .probe          = bfin_serial_probe,
1004         .remove         = bfin_serial_remove,
1005         .suspend        = bfin_serial_suspend,
1006         .resume         = bfin_serial_resume,
1007         .driver         = {
1008                 .name   = "bfin-uart",
1009         },
1010 };
1011
1012 static int __init bfin_serial_init(void)
1013 {
1014         int ret;
1015
1016         pr_info("Serial: Blackfin serial driver\n");
1017
1018         bfin_serial_init_ports();
1019
1020         ret = uart_register_driver(&bfin_serial_reg);
1021         if (ret == 0) {
1022                 ret = platform_driver_register(&bfin_serial_driver);
1023                 if (ret) {
1024                         pr_debug("uart register failed\n");
1025                         uart_unregister_driver(&bfin_serial_reg);
1026                 }
1027         }
1028         return ret;
1029 }
1030
1031 static void __exit bfin_serial_exit(void)
1032 {
1033         platform_driver_unregister(&bfin_serial_driver);
1034         uart_unregister_driver(&bfin_serial_reg);
1035 }
1036
1037 module_init(bfin_serial_init);
1038 module_exit(bfin_serial_exit);
1039
1040 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1041 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1042 MODULE_LICENSE("GPL");
1043 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);