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 #ifdef CONFIG_KGDB_UART
  45 #include <linux/kgdb.h>
  46 #include <asm/irq_regs.h>
  47 #endif
  48
  49 #include <asm/gpio.h>
  50 #include <asm/mach/bfin_serial_5xx.h>
  51
  52 #ifdef CONFIG_SERIAL_BFIN_DMA
  53 #include <linux/dma-mapping.h>
  54 #include <asm/io.h>
  55 #include <asm/irq.h>
  56 #include <asm/cacheflush.h>
  57 #endif
  58
  59 /* UART name and device definitions */
  60 #define BFIN_SERIAL_NAME        "ttyBF"
  61 #define BFIN_SERIAL_MAJOR       204
  62 #define BFIN_SERIAL_MINOR       64
  63
  64 /*
  65  * Setup for console. Argument comes from the menuconfig
  66  */
  67 #define DMA_RX_XCOUNT           512
  68 #define DMA_RX_YCOUNT           (PAGE_SIZE / DMA_RX_XCOUNT)
  69
  70 #define DMA_RX_FLUSH_JIFFIES    5
  71
  72 #ifdef CONFIG_SERIAL_BFIN_DMA
  73 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
  74 #else
  75 static void bfin_serial_do_work(struct work_struct *work);
  76 static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
  77 static void local_put_char(struct bfin_serial_port *uart, char ch);
  78 #endif
  79
  80 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
  81
  82 /*
  83  * interrupts are disabled on entry
  84  */
  85 static void bfin_serial_stop_tx(struct uart_port *port)
  86 {
  87         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
  88
  89 #ifdef CONFIG_BF54x
  90         while (!(UART_GET_LSR(uart) & TEMT))
  91                 continue;
  92 #endif
  93
  94 #ifdef CONFIG_SERIAL_BFIN_DMA
  95         disable_dma(uart->tx_dma_channel);
  96 #else
  97 #ifdef CONFIG_BF54x
  98         /* Waiting for Transmission Finished */
  99         while (!(UART_GET_LSR(uart) & TFI))
 100                 continue;
 101         /* Clear TFI bit */
 102         UART_PUT_LSR(uart, TFI);
 103         UART_CLEAR_IER(uart, ETBEI);
 104 #else
 105         unsigned short ier;
 106
 107         ier = UART_GET_IER(uart);
 108         ier &= ~ETBEI;
 109         UART_PUT_IER(uart, ier);
 110 #endif
 111 #endif
 112 }
 113
 114 /*
 115  * port is locked and interrupts are disabled
 116  */
 117 static void bfin_serial_start_tx(struct uart_port *port)
 118 {
 119         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 120
 121 #ifdef CONFIG_SERIAL_BFIN_DMA
 122         bfin_serial_dma_tx_chars(uart);
 123 #else
 124 #ifdef CONFIG_BF54x
 125         UART_SET_IER(uart, ETBEI);
 126 #else
 127         unsigned short ier;
 128         ier = UART_GET_IER(uart);
 129         ier |= ETBEI;
 130         UART_PUT_IER(uart, ier);
 131         bfin_serial_tx_chars(uart);
 132 #endif
 133 #endif
 134 }
 135
 136 /*
 137  * Interrupts are enabled
 138  */
 139 static void bfin_serial_stop_rx(struct uart_port *port)
 140 {
 141         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 142 #ifdef CONFIG_BF54x
 143         UART_CLEAR_IER(uart, ERBFI);
 144 #else
 145         unsigned short ier;
 146
 147         ier = UART_GET_IER(uart);
 148 #ifdef  CONFIG_KGDB_UART
 149         if (uart->port.line != CONFIG_KGDB_UART_PORT)
 150 #endif
 151         ier &= ~ERBFI;
 152         UART_PUT_IER(uart, ier);
 153 #endif
 154 }
 155
 156 /*
 157  * Set the modem control timer to fire immediately.
 158  */
 159 static void bfin_serial_enable_ms(struct uart_port *port)
 160 {
 161 }
 162
 163 #ifdef CONFIG_KGDB_UART
 164 static int kgdb_entry_state;
 165
 166 void kgdb_put_debug_char(int chr)
 167 {
 168         struct bfin_serial_port *uart;
 169
 170         if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
 171                 uart = &bfin_serial_ports[0];
 172         else
 173                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
 174
 175         while (!(UART_GET_LSR(uart) & THRE)) {
 176                 __builtin_bfin_ssync();
 177         }
 178         UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
 179         __builtin_bfin_ssync();
 180         UART_PUT_CHAR(uart, (unsigned char)chr);
 181         __builtin_bfin_ssync();
 182 }
 183
 184 int kgdb_get_debug_char(void)
 185 {
 186         struct bfin_serial_port *uart;
 187         unsigned char chr;
 188
 189         if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
 190                 uart = &bfin_serial_ports[0];
 191         else
 192                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
 193
 194         while(!(UART_GET_LSR(uart) & DR)) {
 195                 __builtin_bfin_ssync();
 196         }
 197         UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
 198         __builtin_bfin_ssync();
 199         chr = UART_GET_CHAR(uart);
 200         __builtin_bfin_ssync();
 201
 202         return chr;
 203 }
 204 #endif
 205
 206 #ifdef CONFIG_SERIAL_BFIN_PIO
 207 static void local_put_char(struct bfin_serial_port *uart, char ch)
 208 {
 209         unsigned short status;
 210         int flags = 0;
 211
 212         spin_lock_irqsave(&uart->port.lock, flags);
 213
 214         do {
 215                 status = UART_GET_LSR(uart);
 216         } while (!(status & THRE));
 217
 218         UART_PUT_CHAR(uart, ch);
 219         SSYNC();
 220
 221         spin_unlock_irqrestore(&uart->port.lock, flags);
 222 }
 223
 224 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
 225 {
 226         struct tty_struct *tty = uart->port.info->tty;
 227         unsigned int status, ch, flg;
 228 #ifdef CONFIG_KGDB_UART
 229         struct pt_regs *regs = get_irq_regs();
 230 #endif
 231 #ifdef BF533_FAMILY
 232         static int in_break = 0;
 233 #endif
 234
 235         status = UART_GET_LSR(uart);
 236         ch = UART_GET_CHAR(uart);
 237         uart->port.icount.rx++;
 238
 239 #ifdef CONFIG_KGDB_UART
 240         if (uart->port.line == CONFIG_KGDB_UART_PORT) {
 241                 if (uart->port.cons->index == CONFIG_KGDB_UART_PORT && ch == 0x1) { /* Ctrl + A */
 242                         kgdb_breakkey_pressed(regs);
 243                         return;
 244                 } else if (kgdb_entry_state == 0 && ch == '$') {/* connection from KGDB */
 245                         kgdb_entry_state = 1;
 246                 } else if (kgdb_entry_state == 1 && ch == 'q') {
 247                         kgdb_entry_state = 0;
 248                         kgdb_breakkey_pressed(regs);
 249                         return;
 250                 } else if (ch == 0x3) {/* Ctrl + C */
 251                         kgdb_entry_state = 0;
 252                         kgdb_breakkey_pressed(regs);
 253                         return;
 254                 } else {
 255                         kgdb_entry_state = 0;
 256                 }
 257         }
 258 #endif
 259
 260 #ifdef BF533_FAMILY
 261         /* The BF533 family of processors have a nice misbehavior where
 262          * they continuously generate characters for a "single" break.
 263          * We have to basically ignore this flood until the "next" valid
 264          * character comes across.  All other Blackfin families operate
 265          * properly though.
 266          */
 267         if (in_break) {
 268                 if (ch != 0) {
 269                         in_break = 0;
 270                         ch = UART_GET_CHAR(uart);
 271                         if (bfin_revid() < 5)
 272                                 return;
 273                 } else
 274                         return;
 275         }
 276 #endif
 277
 278         if (status & BI) {
 279 #ifdef BF533_FAMILY
 280                 in_break = 1;
 281 #endif
 282                 uart->port.icount.brk++;
 283                 if (uart_handle_break(&uart->port))
 284                         goto ignore_char;
 285                 status &= ~(PE | FE);
 286         }
 287         if (status & PE)
 288                 uart->port.icount.parity++;
 289         if (status & OE)
 290                 uart->port.icount.overrun++;
 291         if (status & FE)
 292                 uart->port.icount.frame++;
 293
 294         status &= uart->port.read_status_mask;
 295
 296         if (status & BI)
 297                 flg = TTY_BREAK;
 298         else if (status & PE)
 299                 flg = TTY_PARITY;
 300         else if (status & FE)
 301                 flg = TTY_FRAME;
 302         else
 303                 flg = TTY_NORMAL;
 304
 305         if (uart_handle_sysrq_char(&uart->port, ch))
 306                 goto ignore_char;
 307
 308         uart_insert_char(&uart->port, status, OE, ch, flg);
 309
 310  ignore_char:
 311         tty_flip_buffer_push(tty);
 312 }
 313
 314 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
 315 {
 316         struct circ_buf *xmit = &uart->port.info->xmit;
 317
 318         if (uart->port.x_char) {
 319                 UART_PUT_CHAR(uart, uart->port.x_char);
 320                 uart->port.icount.tx++;
 321                 uart->port.x_char = 0;
 322                 return;
 323         }
 324         /*
 325          * Check the modem control lines before
 326          * transmitting anything.
 327          */
 328         bfin_serial_mctrl_check(uart);
 329
 330         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
 331                 bfin_serial_stop_tx(&uart->port);
 332                 return;
 333         }
 334
 335         local_put_char(uart, xmit->buf[xmit->tail]);
 336         xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 337         uart->port.icount.tx++;
 338
 339         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 340                 uart_write_wakeup(&uart->port);
 341
 342         if (uart_circ_empty(xmit))
 343                 bfin_serial_stop_tx(&uart->port);
 344 }
 345
 346 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
 347 {
 348         struct bfin_serial_port *uart = dev_id;
 349
 350 #ifdef CONFIG_BF54x
 351         unsigned short status;
 352         spin_lock(&uart->port.lock);
 353         status = UART_GET_LSR(uart);
 354         while ((UART_GET_IER(uart) & ERBFI) && (status & DR)) {
 355                 bfin_serial_rx_chars(uart);
 356                 status = UART_GET_LSR(uart);
 357         }
 358         spin_unlock(&uart->port.lock);
 359 #else
 360         spin_lock(&uart->port.lock);
 361         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_RX_READY)
 362                 bfin_serial_rx_chars(uart);
 363         spin_unlock(&uart->port.lock);
 364 #endif
 365         return IRQ_HANDLED;
 366 }
 367
 368 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
 369 {
 370         struct bfin_serial_port *uart = dev_id;
 371
 372 #ifdef CONFIG_BF54x
 373         unsigned short status;
 374         spin_lock(&uart->port.lock);
 375         status = UART_GET_LSR(uart);
 376         while ((UART_GET_IER(uart) & ETBEI) && (status & THRE)) {
 377                 bfin_serial_tx_chars(uart);
 378                 status = UART_GET_LSR(uart);
 379         }
 380         spin_unlock(&uart->port.lock);
 381 #else
 382         spin_lock(&uart->port.lock);
 383         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_TX_READY)
 384                 bfin_serial_tx_chars(uart);
 385         spin_unlock(&uart->port.lock);
 386 #endif
 387         return IRQ_HANDLED;
 388 }
 389
 390
 391 static void bfin_serial_do_work(struct work_struct *work)
 392 {
 393         struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
 394
 395         bfin_serial_mctrl_check(uart);
 396 }
 397 #endif
 398
 399 #ifdef CONFIG_SERIAL_BFIN_DMA
 400 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
 401 {
 402         struct circ_buf *xmit = &uart->port.info->xmit;
 403         unsigned short ier;
 404         int flags = 0;
 405
 406         if (!uart->tx_done)
 407                 return;
 408
 409         uart->tx_done = 0;
 410
 411         if (uart->port.x_char) {
 412                 UART_PUT_CHAR(uart, uart->port.x_char);
 413                 uart->port.icount.tx++;
 414                 uart->port.x_char = 0;
 415                 uart->tx_done = 1;
 416                 return;
 417         }
 418         /*
 419          * Check the modem control lines before
 420          * transmitting anything.
 421          */
 422         bfin_serial_mctrl_check(uart);
 423
 424         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
 425                 bfin_serial_stop_tx(&uart->port);
 426                 uart->tx_done = 1;
 427                 return;
 428         }
 429
 430         spin_lock_irqsave(&uart->port.lock, flags);
 431         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
 432         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
 433                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
 434         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
 435                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
 436         set_dma_config(uart->tx_dma_channel,
 437                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
 438                         INTR_ON_BUF,
 439                         DIMENSION_LINEAR,
 440                         DATA_SIZE_8));
 441         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
 442         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
 443         set_dma_x_modify(uart->tx_dma_channel, 1);
 444         enable_dma(uart->tx_dma_channel);
 445 #ifdef CONFIG_BF54x
 446         UART_SET_IER(uart, ETBEI);
 447 #else
 448         ier = UART_GET_IER(uart);
 449         ier |= ETBEI;
 450         UART_PUT_IER(uart, ier);
 451 #endif
 452         spin_unlock_irqrestore(&uart->port.lock, flags);
 453 }
 454
 455 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
 456 {
 457         struct tty_struct *tty = uart->port.info->tty;
 458         int i, flg, status;
 459
 460         status = UART_GET_LSR(uart);
 461         uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
 462
 463         if (status & BI) {
 464                 uart->port.icount.brk++;
 465                 if (uart_handle_break(&uart->port))
 466                         goto dma_ignore_char;
 467                 status &= ~(PE | FE);
 468         }
 469         if (status & PE)
 470                 uart->port.icount.parity++;
 471         if (status & OE)
 472                 uart->port.icount.overrun++;
 473         if (status & FE)
 474                 uart->port.icount.frame++;
 475
 476         status &= uart->port.read_status_mask;
 477
 478         if (status & BI)
 479                 flg = TTY_BREAK;
 480         else if (status & PE)
 481                 flg = TTY_PARITY;
 482         else if (status & FE)
 483                 flg = TTY_FRAME;
 484         else
 485                 flg = TTY_NORMAL;
 486
 487         for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) {
 488                 if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
 489                         goto dma_ignore_char;
 490                 uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg);
 491         }
 492
 493  dma_ignore_char:
 494         tty_flip_buffer_push(tty);
 495 }
 496
 497 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
 498 {
 499         int x_pos, pos;
 500         int flags = 0;
 501
 502         bfin_serial_dma_tx_chars(uart);
 503
 504         spin_lock_irqsave(&uart->port.lock, flags);
 505         x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel);
 506         if (x_pos == DMA_RX_XCOUNT)
 507                 x_pos = 0;
 508
 509         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
 510
 511         if (pos>uart->rx_dma_buf.tail) {
 512                 uart->rx_dma_buf.tail = pos;
 513                 bfin_serial_dma_rx_chars(uart);
 514                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
 515         }
 516         spin_unlock_irqrestore(&uart->port.lock, flags);
 517         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
 518         add_timer(&(uart->rx_dma_timer));
 519 }
 520
 521 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
 522 {
 523         struct bfin_serial_port *uart = dev_id;
 524         struct circ_buf *xmit = &uart->port.info->xmit;
 525         unsigned short ier;
 526
 527         spin_lock(&uart->port.lock);
 528         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
 529                 clear_dma_irqstat(uart->tx_dma_channel);
 530                 disable_dma(uart->tx_dma_channel);
 531 #ifdef CONFIG_BF54x
 532                 UART_CLEAR_IER(uart, ETBEI);
 533 #else
 534                 ier = UART_GET_IER(uart);
 535                 ier &= ~ETBEI;
 536                 UART_PUT_IER(uart, ier);
 537 #endif
 538                 xmit->tail = (xmit->tail+uart->tx_count) &(UART_XMIT_SIZE -1);
 539                 uart->port.icount.tx+=uart->tx_count;
 540
 541                 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 542                         uart_write_wakeup(&uart->port);
 543
 544                 if (uart_circ_empty(xmit))
 545                         bfin_serial_stop_tx(&uart->port);
 546                 uart->tx_done = 1;
 547         }
 548
 549         spin_unlock(&uart->port.lock);
 550         return IRQ_HANDLED;
 551 }
 552
 553 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
 554 {
 555         struct bfin_serial_port *uart = dev_id;
 556         unsigned short irqstat;
 557
 558         uart->rx_dma_nrows++;
 559         if (uart->rx_dma_nrows == DMA_RX_YCOUNT) {
 560                 uart->rx_dma_nrows = 0;
 561                 uart->rx_dma_buf.tail = DMA_RX_XCOUNT*DMA_RX_YCOUNT;
 562                 bfin_serial_dma_rx_chars(uart);
 563                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail = 0;
 564         }
 565         spin_lock(&uart->port.lock);
 566         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
 567         clear_dma_irqstat(uart->rx_dma_channel);
 568
 569         spin_unlock(&uart->port.lock);
 570         return IRQ_HANDLED;
 571 }
 572 #endif
 573
 574 /*
 575  * Return TIOCSER_TEMT when transmitter is not busy.
 576  */
 577 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
 578 {
 579         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 580         unsigned short lsr;
 581
 582         lsr = UART_GET_LSR(uart);
 583         if (lsr & TEMT)
 584                 return TIOCSER_TEMT;
 585         else
 586                 return 0;
 587 }
 588
 589 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
 590 {
 591 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 592         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 593         if (uart->cts_pin < 0)
 594                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 595
 596         if (gpio_get_value(uart->cts_pin))
 597                 return TIOCM_DSR | TIOCM_CAR;
 598         else
 599 #endif
 600                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 601 }
 602
 603 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
 604 {
 605 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 606         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 607         if (uart->rts_pin < 0)
 608                 return;
 609
 610         if (mctrl & TIOCM_RTS)
 611                 gpio_set_value(uart->rts_pin, 0);
 612         else
 613                 gpio_set_value(uart->rts_pin, 1);
 614 #endif
 615 }
 616
 617 /*
 618  * Handle any change of modem status signal since we were last called.
 619  */
 620 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
 621 {
 622 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 623         unsigned int status;
 624 # ifdef CONFIG_SERIAL_BFIN_DMA
 625         struct uart_info *info = uart->port.info;
 626         struct tty_struct *tty = info->tty;
 627
 628         status = bfin_serial_get_mctrl(&uart->port);
 629         if (!(status & TIOCM_CTS)) {
 630                 tty->hw_stopped = 1;
 631         } else {
 632                 tty->hw_stopped = 0;
 633         }
 634 # else
 635         status = bfin_serial_get_mctrl(&uart->port);
 636         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
 637         if (!(status & TIOCM_CTS))
 638                 schedule_work(&uart->cts_workqueue);
 639 # endif
 640 #endif
 641 }
 642
 643 /*
 644  * Interrupts are always disabled.
 645  */
 646 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
 647 {
 648         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 649         u16 lcr = UART_GET_LCR(uart);
 650         if (break_state)
 651                 lcr |= SB;
 652         else
 653                 lcr &= ~SB;
 654         UART_PUT_LCR(uart, lcr);
 655         SSYNC();
 656 }
 657
 658 static int bfin_serial_startup(struct uart_port *port)
 659 {
 660         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 661
 662 #ifdef CONFIG_SERIAL_BFIN_DMA
 663         dma_addr_t dma_handle;
 664
 665         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
 666                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
 667                 return -EBUSY;
 668         }
 669
 670         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
 671                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
 672                 free_dma(uart->rx_dma_channel);
 673                 return -EBUSY;
 674         }
 675
 676         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
 677         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
 678
 679         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
 680         uart->rx_dma_buf.head = 0;
 681         uart->rx_dma_buf.tail = 0;
 682         uart->rx_dma_nrows = 0;
 683
 684         set_dma_config(uart->rx_dma_channel,
 685                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
 686                                 INTR_ON_ROW, DIMENSION_2D,
 687                                 DATA_SIZE_8));
 688         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
 689         set_dma_x_modify(uart->rx_dma_channel, 1);
 690         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
 691         set_dma_y_modify(uart->rx_dma_channel, 1);
 692         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
 693         enable_dma(uart->rx_dma_channel);
 694
 695         uart->rx_dma_timer.data = (unsigned long)(uart);
 696         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
 697         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
 698         add_timer(&(uart->rx_dma_timer));
 699 #else
 700 # ifdef CONFIG_KGDB_UART
 701         if (uart->port.line != CONFIG_KGDB_UART_PORT && request_irq
 702 # else
 703         if (request_irq
 704 # endif
 705             (uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
 706              "BFIN_UART_RX", uart)) {
 707                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
 708                 return -EBUSY;
 709         }
 710
 711         if (request_irq
 712             (uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
 713              "BFIN_UART_TX", uart)) {
 714                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
 715                 free_irq(uart->port.irq, uart);
 716                 return -EBUSY;
 717         }
 718 #endif
 719 #ifdef CONFIG_BF54x
 720         UART_SET_IER(uart, ERBFI);
 721 #else
 722         UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
 723 #endif
 724         return 0;
 725 }
 726
 727 static void bfin_serial_shutdown(struct uart_port *port)
 728 {
 729         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 730
 731 #ifdef CONFIG_SERIAL_BFIN_DMA
 732         disable_dma(uart->tx_dma_channel);
 733         free_dma(uart->tx_dma_channel);
 734         disable_dma(uart->rx_dma_channel);
 735         free_dma(uart->rx_dma_channel);
 736         del_timer(&(uart->rx_dma_timer));
 737 #else
 738 #ifdef  CONFIG_KGDB_UART
 739         if (uart->port.line != CONFIG_KGDB_UART_PORT)
 740 #endif
 741         free_irq(uart->port.irq, uart);
 742         free_irq(uart->port.irq+1, uart);
 743 #endif
 744 }
 745
 746 static void
 747 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
 748                    struct ktermios *old)
 749 {
 750         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 751         unsigned long flags;
 752         unsigned int baud, quot;
 753         unsigned short val, ier, lsr, lcr = 0;
 754
 755         switch (termios->c_cflag & CSIZE) {
 756         case CS8:
 757                 lcr = WLS(8);
 758                 break;
 759         case CS7:
 760                 lcr = WLS(7);
 761                 break;
 762         case CS6:
 763                 lcr = WLS(6);
 764                 break;
 765         case CS5:
 766                 lcr = WLS(5);
 767                 break;
 768         default:
 769                 printk(KERN_ERR "%s: word lengh not supported\n",
 770                         __FUNCTION__);
 771         }
 772
 773         if (termios->c_cflag & CSTOPB)
 774                 lcr |= STB;
 775         if (termios->c_cflag & PARENB)
 776                 lcr |= PEN;
 777         if (!(termios->c_cflag & PARODD))
 778                 lcr |= EPS;
 779         if (termios->c_cflag & CMSPAR)
 780                 lcr |= STP;
 781
 782         port->read_status_mask = OE;
 783         if (termios->c_iflag & INPCK)
 784                 port->read_status_mask |= (FE | PE);
 785         if (termios->c_iflag & (BRKINT | PARMRK))
 786                 port->read_status_mask |= BI;
 787
 788         /*
 789          * Characters to ignore
 790          */
 791         port->ignore_status_mask = 0;
 792         if (termios->c_iflag & IGNPAR)
 793                 port->ignore_status_mask |= FE | PE;
 794         if (termios->c_iflag & IGNBRK) {
 795                 port->ignore_status_mask |= BI;
 796                 /*
 797                  * If we're ignoring parity and break indicators,
 798                  * ignore overruns too (for real raw support).
 799                  */
 800                 if (termios->c_iflag & IGNPAR)
 801                         port->ignore_status_mask |= OE;
 802         }
 803
 804         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
 805         quot = uart_get_divisor(port, baud);
 806         spin_lock_irqsave(&uart->port.lock, flags);
 807
 808         do {
 809                 lsr = UART_GET_LSR(uart);
 810         } while (!(lsr & TEMT));
 811
 812         /* Disable UART */
 813         ier = UART_GET_IER(uart);
 814 #ifdef CONFIG_BF54x
 815         UART_CLEAR_IER(uart, 0xF);
 816 #else
 817         UART_PUT_IER(uart, 0);
 818 #endif
 819
 820 #ifndef CONFIG_BF54x
 821         /* Set DLAB in LCR to Access DLL and DLH */
 822         val = UART_GET_LCR(uart);
 823         val |= DLAB;
 824         UART_PUT_LCR(uart, val);
 825         SSYNC();
 826 #endif
 827
 828         UART_PUT_DLL(uart, quot & 0xFF);
 829         SSYNC();
 830         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
 831         SSYNC();
 832
 833 #ifndef CONFIG_BF54x
 834         /* Clear DLAB in LCR to Access THR RBR IER */
 835         val = UART_GET_LCR(uart);
 836         val &= ~DLAB;
 837         UART_PUT_LCR(uart, val);
 838         SSYNC();
 839 #endif
 840
 841         UART_PUT_LCR(uart, lcr);
 842
 843         /* Enable UART */
 844 #ifdef CONFIG_BF54x
 845         UART_SET_IER(uart, ier);
 846 #else
 847         UART_PUT_IER(uart, ier);
 848 #endif
 849
 850         val = UART_GET_GCTL(uart);
 851         val |= UCEN;
 852         UART_PUT_GCTL(uart, val);
 853
 854         spin_unlock_irqrestore(&uart->port.lock, flags);
 855 }
 856
 857 static const char *bfin_serial_type(struct uart_port *port)
 858 {
 859         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 860
 861         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
 862 }
 863
 864 /*
 865  * Release the memory region(s) being used by 'port'.
 866  */
 867 static void bfin_serial_release_port(struct uart_port *port)
 868 {
 869 }
 870
 871 /*
 872  * Request the memory region(s) being used by 'port'.
 873  */
 874 static int bfin_serial_request_port(struct uart_port *port)
 875 {
 876         return 0;
 877 }
 878
 879 /*
 880  * Configure/autoconfigure the port.
 881  */
 882 static void bfin_serial_config_port(struct uart_port *port, int flags)
 883 {
 884         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 885
 886         if (flags & UART_CONFIG_TYPE &&
 887             bfin_serial_request_port(&uart->port) == 0)
 888                 uart->port.type = PORT_BFIN;
 889 }
 890
 891 /*
 892  * Verify the new serial_struct (for TIOCSSERIAL).
 893  * The only change we allow are to the flags and type, and
 894  * even then only between PORT_BFIN and PORT_UNKNOWN
 895  */
 896 static int
 897 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
 898 {
 899         return 0;
 900 }
 901
 902 static struct uart_ops bfin_serial_pops = {
 903         .tx_empty       = bfin_serial_tx_empty,
 904         .set_mctrl      = bfin_serial_set_mctrl,
 905         .get_mctrl      = bfin_serial_get_mctrl,
 906         .stop_tx        = bfin_serial_stop_tx,
 907         .start_tx       = bfin_serial_start_tx,
 908         .stop_rx        = bfin_serial_stop_rx,
 909         .enable_ms      = bfin_serial_enable_ms,
 910         .break_ctl      = bfin_serial_break_ctl,
 911         .startup        = bfin_serial_startup,
 912         .shutdown       = bfin_serial_shutdown,
 913         .set_termios    = bfin_serial_set_termios,
 914         .type           = bfin_serial_type,
 915         .release_port   = bfin_serial_release_port,
 916         .request_port   = bfin_serial_request_port,
 917         .config_port    = bfin_serial_config_port,
 918         .verify_port    = bfin_serial_verify_port,
 919 };
 920
 921 static void __init bfin_serial_init_ports(void)
 922 {
 923         static int first = 1;
 924         int i;
 925
 926         if (!first)
 927                 return;
 928         first = 0;
 929
 930         for (i = 0; i < nr_ports; i++) {
 931                 bfin_serial_ports[i].port.uartclk   = get_sclk();
 932                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
 933                 bfin_serial_ports[i].port.line      = i;
 934                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
 935                 bfin_serial_ports[i].port.membase   =
 936                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
 937                 bfin_serial_ports[i].port.mapbase   =
 938                         bfin_serial_resource[i].uart_base_addr;
 939                 bfin_serial_ports[i].port.irq       =
 940                         bfin_serial_resource[i].uart_irq;
 941                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
 942 #ifdef CONFIG_SERIAL_BFIN_DMA
 943                 bfin_serial_ports[i].tx_done        = 1;
 944                 bfin_serial_ports[i].tx_count       = 0;
 945                 bfin_serial_ports[i].tx_dma_channel =
 946                         bfin_serial_resource[i].uart_tx_dma_channel;
 947                 bfin_serial_ports[i].rx_dma_channel =
 948                         bfin_serial_resource[i].uart_rx_dma_channel;
 949                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
 950 #else
 951                 INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
 952 #endif
 953 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 954                 bfin_serial_ports[i].cts_pin        =
 955                         bfin_serial_resource[i].uart_cts_pin;
 956                 bfin_serial_ports[i].rts_pin        =
 957                         bfin_serial_resource[i].uart_rts_pin;
 958 #endif
 959                 bfin_serial_hw_init(&bfin_serial_ports[i]);
 960         }
 961
 962 }
 963
 964 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
 965 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
 966 {
 967         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 968         while (!(UART_GET_LSR(uart) & THRE))
 969                 barrier();
 970         UART_PUT_CHAR(uart, ch);
 971         SSYNC();
 972 }
 973
 974 /*
 975  * Interrupts are disabled on entering
 976  */
 977 static void
 978 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
 979 {
 980         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
 981         int flags = 0;
 982
 983         spin_lock_irqsave(&uart->port.lock, flags);
 984         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
 985         spin_unlock_irqrestore(&uart->port.lock, flags);
 986
 987 }
 988
 989 /*
 990  * If the port was already initialised (eg, by a boot loader),
 991  * try to determine the current setup.
 992  */
 993 static void __init
 994 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
 995                            int *parity, int *bits)
 996 {
 997         unsigned short status;
 998
 999         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
1000         if (status == (ERBFI | ETBEI)) {
1001                 /* ok, the port was enabled */
1002                 unsigned short lcr, val;
1003                 unsigned short dlh, dll;
1004
1005                 lcr = UART_GET_LCR(uart);
1006
1007                 *parity = 'n';
1008                 if (lcr & PEN) {
1009                         if (lcr & EPS)
1010                                 *parity = 'e';
1011                         else
1012                                 *parity = 'o';
1013                 }
1014                 switch (lcr & 0x03) {
1015                         case 0: *bits = 5; break;
1016                         case 1: *bits = 6; break;
1017                         case 2: *bits = 7; break;
1018                         case 3: *bits = 8; break;
1019                 }
1020 #ifndef CONFIG_BF54x
1021                 /* Set DLAB in LCR to Access DLL and DLH */
1022                 val = UART_GET_LCR(uart);
1023                 val |= DLAB;
1024                 UART_PUT_LCR(uart, val);
1025 #endif
1026
1027                 dll = UART_GET_DLL(uart);
1028                 dlh = UART_GET_DLH(uart);
1029
1030 #ifndef CONFIG_BF54x
1031                 /* Clear DLAB in LCR to Access THR RBR IER */
1032                 val = UART_GET_LCR(uart);
1033                 val &= ~DLAB;
1034                 UART_PUT_LCR(uart, val);
1035 #endif
1036
1037                 *baud = get_sclk() / (16*(dll | dlh << 8));
1038         }
1039         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
1040 }
1041
1042 static int __init
1043 bfin_serial_console_setup(struct console *co, char *options)
1044 {
1045         struct bfin_serial_port *uart;
1046         int baud = 57600;
1047         int bits = 8;
1048         int parity = 'n';
1049 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1050         int flow = 'r';
1051 #else
1052         int flow = 'n';
1053 #endif
1054
1055         /*
1056          * Check whether an invalid uart number has been specified, and
1057          * if so, search for the first available port that does have
1058          * console support.
1059          */
1060         if (co->index == -1 || co->index >= nr_ports)
1061                 co->index = 0;
1062         uart = &bfin_serial_ports[co->index];
1063
1064         if (options)
1065                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1066         else
1067                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
1068
1069         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
1070 }
1071
1072 static struct uart_driver bfin_serial_reg;
1073 static struct console bfin_serial_console = {
1074         .name           = BFIN_SERIAL_NAME,
1075         .write          = bfin_serial_console_write,
1076         .device         = uart_console_device,
1077         .setup          = bfin_serial_console_setup,
1078         .flags          = CON_PRINTBUFFER,
1079         .index          = -1,
1080         .data           = &bfin_serial_reg,
1081 };
1082
1083 static int __init bfin_serial_rs_console_init(void)
1084 {
1085         bfin_serial_init_ports();
1086         register_console(&bfin_serial_console);
1087 #ifdef CONFIG_KGDB_UART
1088         kgdb_entry_state = 0;
1089         init_kgdb_uart();
1090 #endif
1091         return 0;
1092 }
1093 console_initcall(bfin_serial_rs_console_init);
1094
1095 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
1096 #else
1097 #define BFIN_SERIAL_CONSOLE     NULL
1098 #endif
1099
1100 static struct uart_driver bfin_serial_reg = {
1101         .owner                  = THIS_MODULE,
1102         .driver_name            = "bfin-uart",
1103         .dev_name               = BFIN_SERIAL_NAME,
1104         .major                  = BFIN_SERIAL_MAJOR,
1105         .minor                  = BFIN_SERIAL_MINOR,
1106         .nr                     = NR_PORTS,
1107         .cons                   = BFIN_SERIAL_CONSOLE,
1108 };
1109
1110 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
1111 {
1112         struct bfin_serial_port *uart = platform_get_drvdata(dev);
1113
1114         if (uart)
1115                 uart_suspend_port(&bfin_serial_reg, &uart->port);
1116
1117         return 0;
1118 }
1119
1120 static int bfin_serial_resume(struct platform_device *dev)
1121 {
1122         struct bfin_serial_port *uart = platform_get_drvdata(dev);
1123
1124         if (uart)
1125                 uart_resume_port(&bfin_serial_reg, &uart->port);
1126
1127         return 0;
1128 }
1129
1130 static int bfin_serial_probe(struct platform_device *dev)
1131 {
1132         struct resource *res = dev->resource;
1133         int i;
1134
1135         for (i = 0; i < dev->num_resources; i++, res++)
1136                 if (res->flags & IORESOURCE_MEM)
1137                         break;
1138
1139         if (i < dev->num_resources) {
1140                 for (i = 0; i < nr_ports; i++, res++) {
1141                         if (bfin_serial_ports[i].port.mapbase != res->start)
1142                                 continue;
1143                         bfin_serial_ports[i].port.dev = &dev->dev;
1144                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1145                         platform_set_drvdata(dev, &bfin_serial_ports[i]);
1146                 }
1147         }
1148
1149         return 0;
1150 }
1151
1152 static int bfin_serial_remove(struct platform_device *pdev)
1153 {
1154         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
1155
1156
1157 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1158         gpio_free(uart->cts_pin);
1159         gpio_free(uart->rts_pin);
1160 #endif
1161
1162         platform_set_drvdata(pdev, NULL);
1163
1164         if (uart)
1165                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
1166
1167         return 0;
1168 }
1169
1170 static struct platform_driver bfin_serial_driver = {
1171         .probe          = bfin_serial_probe,
1172         .remove         = bfin_serial_remove,
1173         .suspend        = bfin_serial_suspend,
1174         .resume         = bfin_serial_resume,
1175         .driver         = {
1176                 .name   = "bfin-uart",
1177         },
1178 };
1179
1180 static int __init bfin_serial_init(void)
1181 {
1182         int ret;
1183 #ifdef CONFIG_KGDB_UART
1184         struct bfin_serial_port *uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
1185         struct termios t;
1186 #endif
1187
1188         pr_info("Serial: Blackfin serial driver\n");
1189
1190         bfin_serial_init_ports();
1191
1192         ret = uart_register_driver(&bfin_serial_reg);
1193         if (ret == 0) {
1194                 ret = platform_driver_register(&bfin_serial_driver);
1195                 if (ret) {
1196                         pr_debug("uart register failed\n");
1197                         uart_unregister_driver(&bfin_serial_reg);
1198                 }
1199         }
1200 #ifdef CONFIG_KGDB_UART
1201         if (uart->port.cons->index != CONFIG_KGDB_UART_PORT) {
1202                 request_irq(uart->port.irq, bfin_serial_int,
1203                         IRQF_DISABLED, "BFIN_UART_RX", uart);
1204                 pr_info("Request irq for kgdb uart port\n");
1205                 UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
1206                 __builtin_bfin_ssync();
1207                 t.c_cflag = CS8|B57600;
1208                 t.c_iflag = 0;
1209                 t.c_oflag = 0;
1210                 t.c_lflag = ICANON;
1211                 t.c_line = CONFIG_KGDB_UART_PORT;
1212                 bfin_serial_set_termios(&uart->port, &t, &t);
1213         }
1214 #endif
1215         return ret;
1216 }
1217
1218 static void __exit bfin_serial_exit(void)
1219 {
1220         platform_driver_unregister(&bfin_serial_driver);
1221         uart_unregister_driver(&bfin_serial_reg);
1222 }
1223
1224 module_init(bfin_serial_init);
1225 module_exit(bfin_serial_exit);
1226
1227 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1228 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1229 MODULE_LICENSE("GPL");
1230 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);