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                 if (termios->c_cflag & CMSPAR)
 633                         lcr |= STP;
 634         }
 635
 636         port->read_status_mask = OE;
 637         if (termios->c_iflag & INPCK)
 638                 port->read_status_mask |= (FE | PE);
 639         if (termios->c_iflag & (BRKINT | PARMRK))
 640                 port->read_status_mask |= BI;
 641
 642         /*
 643          * Characters to ignore
 644          */
 645         port->ignore_status_mask = 0;
 646         if (termios->c_iflag & IGNPAR)
 647                 port->ignore_status_mask |= FE | PE;
 648         if (termios->c_iflag & IGNBRK) {
 649                 port->ignore_status_mask |= BI;
 650                 /*
 651                  * If we're ignoring parity and break indicators,
 652                  * ignore overruns too (for real raw support).
 653                  */
 654                 if (termios->c_iflag & IGNPAR)
 655                         port->ignore_status_mask |= OE;
 656         }
 657
 658         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
 659         quot = uart_get_divisor(port, baud);
 660         spin_lock_irqsave(&uart->port.lock, flags);
 661
 662         do {
 663                 lsr = UART_GET_LSR(uart);
 664         } while (!(lsr & TEMT));
 665
 666         /* Disable UART */
 667         ier = UART_GET_IER(uart);
 668         UART_PUT_IER(uart, 0);
 669
 670         /* Set DLAB in LCR to Access DLL and DLH */
 671         val = UART_GET_LCR(uart);
 672         val |= DLAB;
 673         UART_PUT_LCR(uart, val);
 674         SSYNC();
 675
 676         UART_PUT_DLL(uart, quot & 0xFF);
 677         SSYNC();
 678         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
 679         SSYNC();
 680
 681         /* Clear DLAB in LCR to Access THR RBR IER */
 682         val = UART_GET_LCR(uart);
 683         val &= ~DLAB;
 684         UART_PUT_LCR(uart, val);
 685         SSYNC();
 686
 687         UART_PUT_LCR(uart, lcr);
 688
 689         /* Enable UART */
 690         UART_PUT_IER(uart, ier);
 691
 692         val = UART_GET_GCTL(uart);
 693         val |= UCEN;
 694         UART_PUT_GCTL(uart, val);
 695
 696         spin_unlock_irqrestore(&uart->port.lock, flags);
 697 }
 698
 699 static const char *bfin_serial_type(struct uart_port *port)
 700 {
 701         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 702
 703         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
 704 }
 705
 706 /*
 707  * Release the memory region(s) being used by 'port'.
 708  */
 709 static void bfin_serial_release_port(struct uart_port *port)
 710 {
 711 }
 712
 713 /*
 714  * Request the memory region(s) being used by 'port'.
 715  */
 716 static int bfin_serial_request_port(struct uart_port *port)
 717 {
 718         return 0;
 719 }
 720
 721 /*
 722  * Configure/autoconfigure the port.
 723  */
 724 static void bfin_serial_config_port(struct uart_port *port, int flags)
 725 {
 726         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 727
 728         if (flags & UART_CONFIG_TYPE &&
 729             bfin_serial_request_port(&uart->port) == 0)
 730                 uart->port.type = PORT_BFIN;
 731 }
 732
 733 /*
 734  * Verify the new serial_struct (for TIOCSSERIAL).
 735  * The only change we allow are to the flags and type, and
 736  * even then only between PORT_BFIN and PORT_UNKNOWN
 737  */
 738 static int
 739 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
 740 {
 741         return 0;
 742 }
 743
 744 static struct uart_ops bfin_serial_pops = {
 745         .tx_empty       = bfin_serial_tx_empty,
 746         .set_mctrl      = bfin_serial_set_mctrl,
 747         .get_mctrl      = bfin_serial_get_mctrl,
 748         .stop_tx        = bfin_serial_stop_tx,
 749         .start_tx       = bfin_serial_start_tx,
 750         .stop_rx        = bfin_serial_stop_rx,
 751         .enable_ms      = bfin_serial_enable_ms,
 752         .break_ctl      = bfin_serial_break_ctl,
 753         .startup        = bfin_serial_startup,
 754         .shutdown       = bfin_serial_shutdown,
 755         .set_termios    = bfin_serial_set_termios,
 756         .type           = bfin_serial_type,
 757         .release_port   = bfin_serial_release_port,
 758         .request_port   = bfin_serial_request_port,
 759         .config_port    = bfin_serial_config_port,
 760         .verify_port    = bfin_serial_verify_port,
 761 };
 762
 763 static void __init bfin_serial_init_ports(void)
 764 {
 765         static int first = 1;
 766         int i;
 767
 768         if (!first)
 769                 return;
 770         first = 0;
 771
 772         for (i = 0; i < nr_ports; i++) {
 773                 bfin_serial_ports[i].port.uartclk   = get_sclk();
 774                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
 775                 bfin_serial_ports[i].port.line      = i;
 776                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
 777                 bfin_serial_ports[i].port.membase   =
 778                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
 779                 bfin_serial_ports[i].port.mapbase   =
 780                         bfin_serial_resource[i].uart_base_addr;
 781                 bfin_serial_ports[i].port.irq       =
 782                         bfin_serial_resource[i].uart_irq;
 783                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
 784 #ifdef CONFIG_SERIAL_BFIN_DMA
 785                 bfin_serial_ports[i].tx_done        = 1;
 786                 bfin_serial_ports[i].tx_count       = 0;
 787                 bfin_serial_ports[i].tx_dma_channel =
 788                         bfin_serial_resource[i].uart_tx_dma_channel;
 789                 bfin_serial_ports[i].rx_dma_channel =
 790                         bfin_serial_resource[i].uart_rx_dma_channel;
 791                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
 792 #else
 793                 INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
 794 #endif
 795 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 796                 bfin_serial_ports[i].cts_pin        =
 797                         bfin_serial_resource[i].uart_cts_pin;
 798                 bfin_serial_ports[i].rts_pin        =
 799                         bfin_serial_resource[i].uart_rts_pin;
 800 #endif
 801                 bfin_serial_hw_init(&bfin_serial_ports[i]);
 802
 803         }
 804 }
 805
 806 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
 807 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
 808 {
 809         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 810         while (!(UART_GET_LSR(uart)))
 811                 barrier();
 812         UART_PUT_CHAR(uart, ch);
 813         SSYNC();
 814 }
 815
 816 /*
 817  * Interrupts are disabled on entering
 818  */
 819 static void
 820 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
 821 {
 822         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
 823         int flags = 0;
 824
 825         spin_lock_irqsave(&uart->port.lock, flags);
 826         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
 827         spin_unlock_irqrestore(&uart->port.lock, flags);
 828
 829 }
 830
 831 /*
 832  * If the port was already initialised (eg, by a boot loader),
 833  * try to determine the current setup.
 834  */
 835 static void __init
 836 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
 837                            int *parity, int *bits)
 838 {
 839         unsigned short status;
 840
 841         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
 842         if (status == (ERBFI | ETBEI)) {
 843                 /* ok, the port was enabled */
 844                 unsigned short lcr, val;
 845                 unsigned short dlh, dll;
 846
 847                 lcr = UART_GET_LCR(uart);
 848
 849                 *parity = 'n';
 850                 if (lcr & PEN) {
 851                         if (lcr & EPS)
 852                                 *parity = 'e';
 853                         else
 854                                 *parity = 'o';
 855                 }
 856                 switch (lcr & 0x03) {
 857                         case 0: *bits = 5; break;
 858                         case 1: *bits = 6; break;
 859                         case 2: *bits = 7; break;
 860                         case 3: *bits = 8; break;
 861                 }
 862                 /* Set DLAB in LCR to Access DLL and DLH */
 863                 val = UART_GET_LCR(uart);
 864                 val |= DLAB;
 865                 UART_PUT_LCR(uart, val);
 866
 867                 dll = UART_GET_DLL(uart);
 868                 dlh = UART_GET_DLH(uart);
 869
 870                 /* Clear DLAB in LCR to Access THR RBR IER */
 871                 val = UART_GET_LCR(uart);
 872                 val &= ~DLAB;
 873                 UART_PUT_LCR(uart, val);
 874
 875                 *baud = get_sclk() / (16*(dll | dlh << 8));
 876         }
 877         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
 878 }
 879
 880 static int __init
 881 bfin_serial_console_setup(struct console *co, char *options)
 882 {
 883         struct bfin_serial_port *uart;
 884         int baud = 57600;
 885         int bits = 8;
 886         int parity = 'n';
 887 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 888         int flow = 'r';
 889 #else
 890         int flow = 'n';
 891 #endif
 892
 893         /*
 894          * Check whether an invalid uart number has been specified, and
 895          * if so, search for the first available port that does have
 896          * console support.
 897          */
 898         if (co->index == -1 || co->index >= nr_ports)
 899                 co->index = 0;
 900         uart = &bfin_serial_ports[co->index];
 901
 902         if (options)
 903                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 904         else
 905                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
 906
 907         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
 908 }
 909
 910 static struct uart_driver bfin_serial_reg;
 911 static struct console bfin_serial_console = {
 912         .name           = BFIN_SERIAL_NAME,
 913         .write          = bfin_serial_console_write,
 914         .device         = uart_console_device,
 915         .setup          = bfin_serial_console_setup,
 916         .flags          = CON_PRINTBUFFER,
 917         .index          = -1,
 918         .data           = &bfin_serial_reg,
 919 };
 920
 921 static int __init bfin_serial_rs_console_init(void)
 922 {
 923         bfin_serial_init_ports();
 924         register_console(&bfin_serial_console);
 925         return 0;
 926 }
 927 console_initcall(bfin_serial_rs_console_init);
 928
 929 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
 930 #else
 931 #define BFIN_SERIAL_CONSOLE     NULL
 932 #endif
 933
 934 static struct uart_driver bfin_serial_reg = {
 935         .owner                  = THIS_MODULE,
 936         .driver_name            = "bfin-uart",
 937         .dev_name               = BFIN_SERIAL_NAME,
 938         .major                  = BFIN_SERIAL_MAJOR,
 939         .minor                  = BFIN_SERIAL_MINOR,
 940         .nr                     = NR_PORTS,
 941         .cons                   = BFIN_SERIAL_CONSOLE,
 942 };
 943
 944 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
 945 {
 946         struct bfin_serial_port *uart = platform_get_drvdata(dev);
 947
 948         if (uart)
 949                 uart_suspend_port(&bfin_serial_reg, &uart->port);
 950
 951         return 0;
 952 }
 953
 954 static int bfin_serial_resume(struct platform_device *dev)
 955 {
 956         struct bfin_serial_port *uart = platform_get_drvdata(dev);
 957
 958         if (uart)
 959                 uart_resume_port(&bfin_serial_reg, &uart->port);
 960
 961         return 0;
 962 }
 963
 964 static int bfin_serial_probe(struct platform_device *dev)
 965 {
 966         struct resource *res = dev->resource;
 967         int i;
 968
 969         for (i = 0; i < dev->num_resources; i++, res++)
 970                 if (res->flags & IORESOURCE_MEM)
 971                         break;
 972
 973         if (i < dev->num_resources) {
 974                 for (i = 0; i < nr_ports; i++, res++) {
 975                         if (bfin_serial_ports[i].port.mapbase != res->start)
 976                                 continue;
 977                         bfin_serial_ports[i].port.dev = &dev->dev;
 978                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
 979                         platform_set_drvdata(dev, &bfin_serial_ports[i]);
 980                 }
 981         }
 982
 983         return 0;
 984 }
 985
 986 static int bfin_serial_remove(struct platform_device *pdev)
 987 {
 988         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
 989
 990
 991 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 992         gpio_free(uart->cts_pin);
 993         gpio_free(uart->rts_pin);
 994 #endif
 995
 996         platform_set_drvdata(pdev, NULL);
 997
 998         if (uart)
 999                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
1000
1001         return 0;
1002 }
1003
1004 static struct platform_driver bfin_serial_driver = {
1005         .probe          = bfin_serial_probe,
1006         .remove         = bfin_serial_remove,
1007         .suspend        = bfin_serial_suspend,
1008         .resume         = bfin_serial_resume,
1009         .driver         = {
1010                 .name   = "bfin-uart",
1011         },
1012 };
1013
1014 static int __init bfin_serial_init(void)
1015 {
1016         int ret;
1017
1018         pr_info("Serial: Blackfin serial driver\n");
1019
1020         bfin_serial_init_ports();
1021
1022         ret = uart_register_driver(&bfin_serial_reg);
1023         if (ret == 0) {
1024                 ret = platform_driver_register(&bfin_serial_driver);
1025                 if (ret) {
1026                         pr_debug("uart register failed\n");
1027                         uart_unregister_driver(&bfin_serial_reg);
1028                 }
1029         }
1030         return ret;
1031 }
1032
1033 static void __exit bfin_serial_exit(void)
1034 {
1035         platform_driver_unregister(&bfin_serial_driver);
1036         uart_unregister_driver(&bfin_serial_reg);
1037 }
1038
1039 module_init(bfin_serial_init);
1040 module_exit(bfin_serial_exit);
1041
1042 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1043 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1044 MODULE_LICENSE("GPL");
1045 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);