drivers/tty/serial/bfin_uart.c

   1 /*
   2  * Blackfin On-Chip Serial Driver
   3  *
   4  * Copyright 2006-2011 Analog Devices Inc.
   5  *
   6  * Enter bugs at http://blackfin.uclinux.org/
   7  *
   8  * Licensed under the GPL-2 or later.
   9  */
  10
  11 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  12 #define SUPPORT_SYSRQ
  13 #endif
  14
  15 #define DRIVER_NAME "bfin-uart"
  16 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
  17
  18 #include <linux/module.h>
  19 #include <linux/ioport.h>
  20 #include <linux/gfp.h>
  21 #include <linux/io.h>
  22 #include <linux/init.h>
  23 #include <linux/console.h>
  24 #include <linux/sysrq.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/tty.h>
  27 #include <linux/tty_flip.h>
  28 #include <linux/serial_core.h>
  29 #include <linux/gpio.h>
  30 #include <linux/irq.h>
  31 #include <linux/kgdb.h>
  32 #include <linux/slab.h>
  33 #include <linux/dma-mapping.h>
  34
  35 #include <asm/portmux.h>
  36 #include <asm/cacheflush.h>
  37 #include <asm/dma.h>
  38 #include <asm/bfin_serial.h>
  39
  40 #ifdef CONFIG_SERIAL_BFIN_MODULE
  41 # undef CONFIG_EARLY_PRINTK
  42 #endif
  43
  44 #ifdef CONFIG_SERIAL_BFIN_MODULE
  45 # undef CONFIG_EARLY_PRINTK
  46 #endif
  47
  48 /* UART name and device definitions */
  49 #define BFIN_SERIAL_DEV_NAME    "ttyBF"
  50 #define BFIN_SERIAL_MAJOR       204
  51 #define BFIN_SERIAL_MINOR       64
  52
  53 static struct bfin_serial_port *bfin_serial_ports[BFIN_UART_NR_PORTS];
  54
  55 #if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
  56         defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
  57
  58 # ifndef CONFIG_SERIAL_BFIN_PIO
  59 #  error KGDB only support UART in PIO mode.
  60 # endif
  61
  62 static int kgdboc_port_line;
  63 static int kgdboc_break_enabled;
  64 #endif
  65 /*
  66  * Setup for console. Argument comes from the menuconfig
  67  */
  68 #define DMA_RX_XCOUNT           512
  69 #define DMA_RX_YCOUNT           (PAGE_SIZE / DMA_RX_XCOUNT)
  70
  71 #define DMA_RX_FLUSH_JIFFIES    (HZ / 50)
  72
  73 #ifdef CONFIG_SERIAL_BFIN_DMA
  74 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
  75 #else
  76 static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
  77 #endif
  78
  79 static void bfin_serial_reset_irda(struct uart_port *port);
  80
  81 #if defined(CONFIG_SERIAL_BFIN_CTSRTS) || \
  82         defined(CONFIG_SERIAL_BFIN_HARD_CTSRTS)
  83 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
  84 {
  85         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
  86         if (uart->cts_pin < 0)
  87                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
  88
  89         /* CTS PIN is negative assertive. */
  90         if (UART_GET_CTS(uart))
  91                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
  92         else
  93                 return TIOCM_DSR | TIOCM_CAR;
  94 }
  95
  96 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
  97 {
  98         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
  99         if (uart->rts_pin < 0)
 100                 return;
 101
 102         /* RTS PIN is negative assertive. */
 103         if (mctrl & TIOCM_RTS)
 104                 UART_ENABLE_RTS(uart);
 105         else
 106                 UART_DISABLE_RTS(uart);
 107 }
 108
 109 /*
 110  * Handle any change of modem status signal.
 111  */
 112 static irqreturn_t bfin_serial_mctrl_cts_int(int irq, void *dev_id)
 113 {
 114         struct bfin_serial_port *uart = dev_id;
 115         unsigned int status = bfin_serial_get_mctrl(&uart->port);
 116 #ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
 117         struct tty_struct *tty = uart->port.state->port.tty;
 118
 119         UART_CLEAR_SCTS(uart);
 120         if (tty->hw_stopped) {
 121                 if (status) {
 122                         tty->hw_stopped = 0;
 123                         uart_write_wakeup(&uart->port);
 124                 }
 125         } else {
 126                 if (!status)
 127                         tty->hw_stopped = 1;
 128         }
 129 #endif
 130         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
 131
 132         return IRQ_HANDLED;
 133 }
 134 #else
 135 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
 136 {
 137         return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 138 }
 139
 140 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
 141 {
 142 }
 143 #endif
 144
 145 /*
 146  * interrupts are disabled on entry
 147  */
 148 static void bfin_serial_stop_tx(struct uart_port *port)
 149 {
 150         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 151 #ifdef CONFIG_SERIAL_BFIN_DMA
 152         struct circ_buf *xmit = &uart->port.state->xmit;
 153 #endif
 154
 155         while (!(UART_GET_LSR(uart) & TEMT))
 156                 cpu_relax();
 157
 158 #ifdef CONFIG_SERIAL_BFIN_DMA
 159         disable_dma(uart->tx_dma_channel);
 160         xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
 161         uart->port.icount.tx += uart->tx_count;
 162         uart->tx_count = 0;
 163         uart->tx_done = 1;
 164 #else
 165 #if defined(CONFIG_BF54x) || defined(CONFIG_BF60x)
 166         /* Clear TFI bit */
 167         UART_PUT_LSR(uart, TFI);
 168 #endif
 169         UART_CLEAR_IER(uart, ETBEI);
 170 #endif
 171 }
 172
 173 /*
 174  * port is locked and interrupts are disabled
 175  */
 176 static void bfin_serial_start_tx(struct uart_port *port)
 177 {
 178         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 179         struct tty_struct *tty = uart->port.state->port.tty;
 180
 181         /*
 182          * To avoid losting RX interrupt, we reset IR function
 183          * before sending data.
 184          */
 185         if (tty->termios.c_line == N_IRDA)
 186                 bfin_serial_reset_irda(port);
 187
 188 #ifdef CONFIG_SERIAL_BFIN_DMA
 189         if (uart->tx_done)
 190                 bfin_serial_dma_tx_chars(uart);
 191 #else
 192         UART_SET_IER(uart, ETBEI);
 193         bfin_serial_tx_chars(uart);
 194 #endif
 195 }
 196
 197 /*
 198  * Interrupts are enabled
 199  */
 200 static void bfin_serial_stop_rx(struct uart_port *port)
 201 {
 202         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 203
 204         UART_CLEAR_IER(uart, ERBFI);
 205 }
 206
 207 /*
 208  * Set the modem control timer to fire immediately.
 209  */
 210 static void bfin_serial_enable_ms(struct uart_port *port)
 211 {
 212 }
 213
 214
 215 #if ANOMALY_05000363 && defined(CONFIG_SERIAL_BFIN_PIO)
 216 # define UART_GET_ANOMALY_THRESHOLD(uart)    ((uart)->anomaly_threshold)
 217 # define UART_SET_ANOMALY_THRESHOLD(uart, v) ((uart)->anomaly_threshold = (v))
 218 #else
 219 # define UART_GET_ANOMALY_THRESHOLD(uart)    0
 220 # define UART_SET_ANOMALY_THRESHOLD(uart, v)
 221 #endif
 222
 223 #ifdef CONFIG_SERIAL_BFIN_PIO
 224 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
 225 {
 226         struct tty_struct *tty = NULL;
 227         unsigned int status, ch, flg;
 228         static struct timeval anomaly_start = { .tv_sec = 0 };
 229
 230         status = UART_GET_LSR(uart);
 231         UART_CLEAR_LSR(uart);
 232
 233         ch = UART_GET_CHAR(uart);
 234         uart->port.icount.rx++;
 235
 236 #if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
 237         defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
 238         if (kgdb_connected && kgdboc_port_line == uart->port.line
 239                 && kgdboc_break_enabled)
 240                 if (ch == 0x3) {/* Ctrl + C */
 241                         kgdb_breakpoint();
 242                         return;
 243                 }
 244
 245         if (!uart->port.state || !uart->port.state->port.tty)
 246                 return;
 247 #endif
 248         tty = uart->port.state->port.tty;
 249
 250         if (ANOMALY_05000363) {
 251                 /* The BF533 (and BF561) family of processors have a nice anomaly
 252                  * where they continuously generate characters for a "single" break.
 253                  * We have to basically ignore this flood until the "next" valid
 254                  * character comes across.  Due to the nature of the flood, it is
 255                  * not possible to reliably catch bytes that are sent too quickly
 256                  * after this break.  So application code talking to the Blackfin
 257                  * which sends a break signal must allow at least 1.5 character
 258                  * times after the end of the break for things to stabilize.  This
 259                  * timeout was picked as it must absolutely be larger than 1
 260                  * character time +/- some percent.  So 1.5 sounds good.  All other
 261                  * Blackfin families operate properly.  Woo.
 262                  */
 263                 if (anomaly_start.tv_sec) {
 264                         struct timeval curr;
 265                         suseconds_t usecs;
 266
 267                         if ((~ch & (~ch + 1)) & 0xff)
 268                                 goto known_good_char;
 269
 270                         do_gettimeofday(&curr);
 271                         if (curr.tv_sec - anomaly_start.tv_sec > 1)
 272                                 goto known_good_char;
 273
 274                         usecs = 0;
 275                         if (curr.tv_sec != anomaly_start.tv_sec)
 276                                 usecs += USEC_PER_SEC;
 277                         usecs += curr.tv_usec - anomaly_start.tv_usec;
 278
 279                         if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
 280                                 goto known_good_char;
 281
 282                         if (ch)
 283                                 anomaly_start.tv_sec = 0;
 284                         else
 285                                 anomaly_start = curr;
 286
 287                         return;
 288
 289  known_good_char:
 290                         status &= ~BI;
 291                         anomaly_start.tv_sec = 0;
 292                 }
 293         }
 294
 295         if (status & BI) {
 296                 if (ANOMALY_05000363)
 297                         if (bfin_revid() < 5)
 298                                 do_gettimeofday(&anomaly_start);
 299                 uart->port.icount.brk++;
 300                 if (uart_handle_break(&uart->port))
 301                         goto ignore_char;
 302                 status &= ~(PE | FE);
 303         }
 304         if (status & PE)
 305                 uart->port.icount.parity++;
 306         if (status & OE)
 307                 uart->port.icount.overrun++;
 308         if (status & FE)
 309                 uart->port.icount.frame++;
 310
 311         status &= uart->port.read_status_mask;
 312
 313         if (status & BI)
 314                 flg = TTY_BREAK;
 315         else if (status & PE)
 316                 flg = TTY_PARITY;
 317         else if (status & FE)
 318                 flg = TTY_FRAME;
 319         else
 320                 flg = TTY_NORMAL;
 321
 322         if (uart_handle_sysrq_char(&uart->port, ch))
 323                 goto ignore_char;
 324
 325         uart_insert_char(&uart->port, status, OE, ch, flg);
 326
 327  ignore_char:
 328         tty_flip_buffer_push(tty);
 329 }
 330
 331 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
 332 {
 333         struct circ_buf *xmit = &uart->port.state->xmit;
 334
 335         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
 336 #if defined(CONFIG_BF54x) || defined(CONFIG_BF60x)
 337                 /* Clear TFI bit */
 338                 UART_PUT_LSR(uart, TFI);
 339 #endif
 340                 /* Anomaly notes:
 341                  *  05000215 -  we always clear ETBEI within last UART TX
 342                  *              interrupt to end a string. It is always set
 343                  *              when start a new tx.
 344                  */
 345                 UART_CLEAR_IER(uart, ETBEI);
 346                 return;
 347         }
 348
 349         if (uart->port.x_char) {
 350                 UART_PUT_CHAR(uart, uart->port.x_char);
 351                 uart->port.icount.tx++;
 352                 uart->port.x_char = 0;
 353         }
 354
 355         while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
 356                 UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
 357                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 358                 uart->port.icount.tx++;
 359         }
 360
 361         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 362                 uart_write_wakeup(&uart->port);
 363 }
 364
 365 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
 366 {
 367         struct bfin_serial_port *uart = dev_id;
 368
 369         while (UART_GET_LSR(uart) & DR)
 370                 bfin_serial_rx_chars(uart);
 371
 372         return IRQ_HANDLED;
 373 }
 374
 375 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
 376 {
 377         struct bfin_serial_port *uart = dev_id;
 378
 379         spin_lock(&uart->port.lock);
 380         if (UART_GET_LSR(uart) & THRE)
 381                 bfin_serial_tx_chars(uart);
 382         spin_unlock(&uart->port.lock);
 383
 384         return IRQ_HANDLED;
 385 }
 386 #endif
 387
 388 #ifdef CONFIG_SERIAL_BFIN_DMA
 389 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
 390 {
 391         struct circ_buf *xmit = &uart->port.state->xmit;
 392
 393         uart->tx_done = 0;
 394
 395         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
 396                 uart->tx_count = 0;
 397                 uart->tx_done = 1;
 398                 return;
 399         }
 400
 401         if (uart->port.x_char) {
 402                 UART_PUT_CHAR(uart, uart->port.x_char);
 403                 uart->port.icount.tx++;
 404                 uart->port.x_char = 0;
 405         }
 406
 407         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
 408         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
 409                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
 410         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
 411                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
 412         set_dma_config(uart->tx_dma_channel,
 413                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
 414                         INTR_ON_BUF,
 415                         DIMENSION_LINEAR,
 416                         DATA_SIZE_8,
 417                         DMA_SYNC_RESTART));
 418         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
 419         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
 420         set_dma_x_modify(uart->tx_dma_channel, 1);
 421         SSYNC();
 422         enable_dma(uart->tx_dma_channel);
 423
 424         UART_SET_IER(uart, ETBEI);
 425 }
 426
 427 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
 428 {
 429         struct tty_struct *tty = uart->port.state->port.tty;
 430         int i, flg, status;
 431
 432         status = UART_GET_LSR(uart);
 433         UART_CLEAR_LSR(uart);
 434
 435         uart->port.icount.rx +=
 436                 CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
 437                 UART_XMIT_SIZE);
 438
 439         if (status & BI) {
 440                 uart->port.icount.brk++;
 441                 if (uart_handle_break(&uart->port))
 442                         goto dma_ignore_char;
 443                 status &= ~(PE | FE);
 444         }
 445         if (status & PE)
 446                 uart->port.icount.parity++;
 447         if (status & OE)
 448                 uart->port.icount.overrun++;
 449         if (status & FE)
 450                 uart->port.icount.frame++;
 451
 452         status &= uart->port.read_status_mask;
 453
 454         if (status & BI)
 455                 flg = TTY_BREAK;
 456         else if (status & PE)
 457                 flg = TTY_PARITY;
 458         else if (status & FE)
 459                 flg = TTY_FRAME;
 460         else
 461                 flg = TTY_NORMAL;
 462
 463         for (i = uart->rx_dma_buf.tail; ; i++) {
 464                 if (i >= UART_XMIT_SIZE)
 465                         i = 0;
 466                 if (i == uart->rx_dma_buf.head)
 467                         break;
 468                 if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
 469                         uart_insert_char(&uart->port, status, OE,
 470                                 uart->rx_dma_buf.buf[i], flg);
 471         }
 472
 473  dma_ignore_char:
 474         tty_flip_buffer_push(tty);
 475 }
 476
 477 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
 478 {
 479         int x_pos, pos;
 480
 481         dma_disable_irq_nosync(uart->rx_dma_channel);
 482         spin_lock_bh(&uart->rx_lock);
 483
 484         /* 2D DMA RX buffer ring is used. Because curr_y_count and
 485          * curr_x_count can't be read as an atomic operation,
 486          * curr_y_count should be read before curr_x_count. When
 487          * curr_x_count is read, curr_y_count may already indicate
 488          * next buffer line. But, the position calculated here is
 489          * still indicate the old line. The wrong position data may
 490          * be smaller than current buffer tail, which cause garbages
 491          * are received if it is not prohibit.
 492          */
 493         uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
 494         x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
 495         uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
 496         if (uart->rx_dma_nrows == DMA_RX_YCOUNT || x_pos == 0)
 497                 uart->rx_dma_nrows = 0;
 498         x_pos = DMA_RX_XCOUNT - x_pos;
 499         if (x_pos == DMA_RX_XCOUNT)
 500                 x_pos = 0;
 501
 502         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
 503         /* Ignore receiving data if new position is in the same line of
 504          * current buffer tail and small.
 505          */
 506         if (pos > uart->rx_dma_buf.tail ||
 507                 uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) {
 508                 uart->rx_dma_buf.head = pos;
 509                 bfin_serial_dma_rx_chars(uart);
 510                 uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
 511         }
 512
 513         spin_unlock_bh(&uart->rx_lock);
 514         dma_enable_irq(uart->rx_dma_channel);
 515
 516         mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
 517 }
 518
 519 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
 520 {
 521         struct bfin_serial_port *uart = dev_id;
 522         struct circ_buf *xmit = &uart->port.state->xmit;
 523
 524         spin_lock(&uart->port.lock);
 525         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
 526                 disable_dma(uart->tx_dma_channel);
 527                 clear_dma_irqstat(uart->tx_dma_channel);
 528                 /* Anomaly notes:
 529                  *  05000215 -  we always clear ETBEI within last UART TX
 530                  *              interrupt to end a string. It is always set
 531                  *              when start a new tx.
 532                  */
 533                 UART_CLEAR_IER(uart, ETBEI);
 534                 uart->port.icount.tx += uart->tx_count;
 535                 if (!(xmit->tail == 0 && xmit->head == 0)) {
 536                         xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
 537
 538                         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 539                                 uart_write_wakeup(&uart->port);
 540                 }
 541
 542                 bfin_serial_dma_tx_chars(uart);
 543         }
 544
 545         spin_unlock(&uart->port.lock);
 546         return IRQ_HANDLED;
 547 }
 548
 549 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
 550 {
 551         struct bfin_serial_port *uart = dev_id;
 552         unsigned int irqstat;
 553         int x_pos, pos;
 554
 555         spin_lock(&uart->rx_lock);
 556         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
 557         clear_dma_irqstat(uart->rx_dma_channel);
 558
 559         uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
 560         x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
 561         uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
 562         if (uart->rx_dma_nrows == DMA_RX_YCOUNT || x_pos == 0)
 563                 uart->rx_dma_nrows = 0;
 564
 565         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT;
 566         if (pos > uart->rx_dma_buf.tail ||
 567                 uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) {
 568                 uart->rx_dma_buf.head = pos;
 569                 bfin_serial_dma_rx_chars(uart);
 570                 uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
 571         }
 572
 573         spin_unlock(&uart->rx_lock);
 574
 575         return IRQ_HANDLED;
 576 }
 577 #endif
 578
 579 /*
 580  * Return TIOCSER_TEMT when transmitter is not busy.
 581  */
 582 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
 583 {
 584         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 585         unsigned int lsr;
 586
 587         lsr = UART_GET_LSR(uart);
 588         if (lsr & TEMT)
 589                 return TIOCSER_TEMT;
 590         else
 591                 return 0;
 592 }
 593
 594 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
 595 {
 596         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 597         u32 lcr = UART_GET_LCR(uart);
 598         if (break_state)
 599                 lcr |= SB;
 600         else
 601                 lcr &= ~SB;
 602         UART_PUT_LCR(uart, lcr);
 603         SSYNC();
 604 }
 605
 606 static int bfin_serial_startup(struct uart_port *port)
 607 {
 608         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 609
 610 #ifdef CONFIG_SERIAL_BFIN_DMA
 611         dma_addr_t dma_handle;
 612
 613         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
 614                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
 615                 return -EBUSY;
 616         }
 617
 618         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
 619                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
 620                 free_dma(uart->rx_dma_channel);
 621                 return -EBUSY;
 622         }
 623
 624         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
 625         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
 626
 627         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
 628         uart->rx_dma_buf.head = 0;
 629         uart->rx_dma_buf.tail = 0;
 630         uart->rx_dma_nrows = 0;
 631
 632         set_dma_config(uart->rx_dma_channel,
 633                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
 634                                 INTR_ON_ROW, DIMENSION_2D,
 635                                 DATA_SIZE_8,
 636                                 DMA_SYNC_RESTART));
 637         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
 638         set_dma_x_modify(uart->rx_dma_channel, 1);
 639         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
 640         set_dma_y_modify(uart->rx_dma_channel, 1);
 641         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
 642         enable_dma(uart->rx_dma_channel);
 643
 644         uart->rx_dma_timer.data = (unsigned long)(uart);
 645         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
 646         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
 647         add_timer(&(uart->rx_dma_timer));
 648 #else
 649 # if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
 650         defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
 651         if (kgdboc_port_line == uart->port.line && kgdboc_break_enabled)
 652                 kgdboc_break_enabled = 0;
 653         else {
 654 # endif
 655         if (request_irq(uart->rx_irq, bfin_serial_rx_int, 0,
 656              "BFIN_UART_RX", uart)) {
 657                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
 658                 return -EBUSY;
 659         }
 660
 661         if (request_irq
 662             (uart->tx_irq, bfin_serial_tx_int, 0,
 663              "BFIN_UART_TX", uart)) {
 664                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
 665                 free_irq(uart->rx_irq, uart);
 666                 return -EBUSY;
 667         }
 668
 669 # ifdef CONFIG_BF54x
 670         {
 671                 /*
 672                  * UART2 and UART3 on BF548 share interrupt PINs and DMA
 673                  * controllers with SPORT2 and SPORT3. UART rx and tx
 674                  * interrupts are generated in PIO mode only when configure
 675                  * their peripheral mapping registers properly, which means
 676                  * request corresponding DMA channels in PIO mode as well.
 677                  */
 678                 unsigned uart_dma_ch_rx, uart_dma_ch_tx;
 679
 680                 switch (uart->rx_irq) {
 681                 case IRQ_UART3_RX:
 682                         uart_dma_ch_rx = CH_UART3_RX;
 683                         uart_dma_ch_tx = CH_UART3_TX;
 684                         break;
 685                 case IRQ_UART2_RX:
 686                         uart_dma_ch_rx = CH_UART2_RX;
 687                         uart_dma_ch_tx = CH_UART2_TX;
 688                         break;
 689                 default:
 690                         uart_dma_ch_rx = uart_dma_ch_tx = 0;
 691                         break;
 692                 };
 693
 694                 if (uart_dma_ch_rx &&
 695                         request_dma(uart_dma_ch_rx, "BFIN_UART_RX") < 0) {
 696                         printk(KERN_NOTICE"Fail to attach UART interrupt\n");
 697                         free_irq(uart->rx_irq, uart);
 698                         free_irq(uart->tx_irq, uart);
 699                         return -EBUSY;
 700                 }
 701                 if (uart_dma_ch_tx &&
 702                         request_dma(uart_dma_ch_tx, "BFIN_UART_TX") < 0) {
 703                         printk(KERN_NOTICE "Fail to attach UART interrupt\n");
 704                         free_dma(uart_dma_ch_rx);
 705                         free_irq(uart->rx_irq, uart);
 706                         free_irq(uart->tx_irq, uart);
 707                         return -EBUSY;
 708                 }
 709         }
 710 # endif
 711 # if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
 712         defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
 713         }
 714 # endif
 715 #endif
 716
 717 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 718         if (uart->cts_pin >= 0) {
 719                 if (request_irq(gpio_to_irq(uart->cts_pin),
 720                         bfin_serial_mctrl_cts_int,
 721                         IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
 722                         0, "BFIN_UART_CTS", uart)) {
 723                         uart->cts_pin = -1;
 724                         pr_info("Unable to attach BlackFin UART CTS interrupt. So, disable it.\n");
 725                 }
 726         }
 727         if (uart->rts_pin >= 0) {
 728                 if (gpio_request(uart->rts_pin, DRIVER_NAME)) {
 729                         pr_info("fail to request RTS PIN at GPIO_%d\n", uart->rts_pin);
 730                         uart->rts_pin = -1;
 731                 } else
 732                         gpio_direction_output(uart->rts_pin, 0);
 733         }
 734 #endif
 735 #ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
 736         if (uart->cts_pin >= 0) {
 737                 if (request_irq(uart->status_irq, bfin_serial_mctrl_cts_int,
 738                         IRQF_DISABLED, "BFIN_UART_MODEM_STATUS", uart)) {
 739                         uart->cts_pin = -1;
 740                         dev_info(port->dev, "Unable to attach BlackFin UART Modem Status interrupt.\n");
 741                 }
 742
 743                 /* CTS RTS PINs are negative assertive. */
 744                 UART_PUT_MCR(uart, UART_GET_MCR(uart) | ACTS);
 745                 UART_SET_IER(uart, EDSSI);
 746         }
 747 #endif
 748
 749         UART_SET_IER(uart, ERBFI);
 750         return 0;
 751 }
 752
 753 static void bfin_serial_shutdown(struct uart_port *port)
 754 {
 755         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 756
 757 #ifdef CONFIG_SERIAL_BFIN_DMA
 758         disable_dma(uart->tx_dma_channel);
 759         free_dma(uart->tx_dma_channel);
 760         disable_dma(uart->rx_dma_channel);
 761         free_dma(uart->rx_dma_channel);
 762         del_timer(&(uart->rx_dma_timer));
 763         dma_free_coherent(NULL, PAGE_SIZE, uart->rx_dma_buf.buf, 0);
 764 #else
 765 #ifdef CONFIG_BF54x
 766         switch (uart->port.irq) {
 767         case IRQ_UART3_RX:
 768                 free_dma(CH_UART3_RX);
 769                 free_dma(CH_UART3_TX);
 770                 break;
 771         case IRQ_UART2_RX:
 772                 free_dma(CH_UART2_RX);
 773                 free_dma(CH_UART2_TX);
 774                 break;
 775         default:
 776                 break;
 777         };
 778 #endif
 779         free_irq(uart->rx_irq, uart);
 780         free_irq(uart->tx_irq, uart);
 781 #endif
 782
 783 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 784         if (uart->cts_pin >= 0)
 785                 free_irq(gpio_to_irq(uart->cts_pin), uart);
 786         if (uart->rts_pin >= 0)
 787                 gpio_free(uart->rts_pin);
 788 #endif
 789 #ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
 790         if (uart->cts_pin >= 0)
 791                 free_irq(uart->status_irq, uart);
 792 #endif
 793 }
 794
 795 static void
 796 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
 797                    struct ktermios *old)
 798 {
 799         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 800         unsigned long flags;
 801         unsigned int baud, quot;
 802         unsigned int ier, lcr = 0;
 803
 804         switch (termios->c_cflag & CSIZE) {
 805         case CS8:
 806                 lcr = WLS(8);
 807                 break;
 808         case CS7:
 809                 lcr = WLS(7);
 810                 break;
 811         case CS6:
 812                 lcr = WLS(6);
 813                 break;
 814         case CS5:
 815                 lcr = WLS(5);
 816                 break;
 817         default:
 818                 printk(KERN_ERR "%s: word length not supported\n",
 819                         __func__);
 820         }
 821
 822         /* Anomaly notes:
 823          *  05000231 -  STOP bit is always set to 1 whatever the user is set.
 824          */
 825         if (termios->c_cflag & CSTOPB) {
 826                 if (ANOMALY_05000231)
 827                         printk(KERN_WARNING "STOP bits other than 1 is not "
 828                                 "supported in case of anomaly 05000231.\n");
 829                 else
 830                         lcr |= STB;
 831         }
 832         if (termios->c_cflag & PARENB)
 833                 lcr |= PEN;
 834         if (!(termios->c_cflag & PARODD))
 835                 lcr |= EPS;
 836         if (termios->c_cflag & CMSPAR)
 837                 lcr |= STP;
 838
 839         spin_lock_irqsave(&uart->port.lock, flags);
 840
 841         port->read_status_mask = OE;
 842         if (termios->c_iflag & INPCK)
 843                 port->read_status_mask |= (FE | PE);
 844         if (termios->c_iflag & (BRKINT | PARMRK))
 845                 port->read_status_mask |= BI;
 846
 847         /*
 848          * Characters to ignore
 849          */
 850         port->ignore_status_mask = 0;
 851         if (termios->c_iflag & IGNPAR)
 852                 port->ignore_status_mask |= FE | PE;
 853         if (termios->c_iflag & IGNBRK) {
 854                 port->ignore_status_mask |= BI;
 855                 /*
 856                  * If we're ignoring parity and break indicators,
 857                  * ignore overruns too (for real raw support).
 858                  */
 859                 if (termios->c_iflag & IGNPAR)
 860                         port->ignore_status_mask |= OE;
 861         }
 862
 863         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
 864         quot = uart_get_divisor(port, baud);
 865
 866         /* If discipline is not IRDA, apply ANOMALY_05000230 */
 867         if (termios->c_line != N_IRDA)
 868                 quot -= ANOMALY_05000230;
 869
 870         UART_SET_ANOMALY_THRESHOLD(uart, USEC_PER_SEC / baud * 15);
 871
 872         /* Disable UART */
 873         ier = UART_GET_IER(uart);
 874         UART_PUT_GCTL(uart, UART_GET_GCTL(uart) & ~UCEN);
 875         UART_DISABLE_INTS(uart);
 876
 877         /* Set DLAB in LCR to Access CLK */
 878         UART_SET_DLAB(uart);
 879
 880         UART_PUT_CLK(uart, quot);
 881         SSYNC();
 882
 883         /* Clear DLAB in LCR to Access THR RBR IER */
 884         UART_CLEAR_DLAB(uart);
 885
 886         UART_PUT_LCR(uart, (UART_GET_LCR(uart) & ~LCR_MASK) | lcr);
 887
 888         /* Enable UART */
 889         UART_ENABLE_INTS(uart, ier);
 890         UART_PUT_GCTL(uart, UART_GET_GCTL(uart) | UCEN);
 891
 892         /* Port speed changed, update the per-port timeout. */
 893         uart_update_timeout(port, termios->c_cflag, baud);
 894
 895         spin_unlock_irqrestore(&uart->port.lock, flags);
 896 }
 897
 898 static const char *bfin_serial_type(struct uart_port *port)
 899 {
 900         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 901
 902         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
 903 }
 904
 905 /*
 906  * Release the memory region(s) being used by 'port'.
 907  */
 908 static void bfin_serial_release_port(struct uart_port *port)
 909 {
 910 }
 911
 912 /*
 913  * Request the memory region(s) being used by 'port'.
 914  */
 915 static int bfin_serial_request_port(struct uart_port *port)
 916 {
 917         return 0;
 918 }
 919
 920 /*
 921  * Configure/autoconfigure the port.
 922  */
 923 static void bfin_serial_config_port(struct uart_port *port, int flags)
 924 {
 925         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 926
 927         if (flags & UART_CONFIG_TYPE &&
 928             bfin_serial_request_port(&uart->port) == 0)
 929                 uart->port.type = PORT_BFIN;
 930 }
 931
 932 /*
 933  * Verify the new serial_struct (for TIOCSSERIAL).
 934  * The only change we allow are to the flags and type, and
 935  * even then only between PORT_BFIN and PORT_UNKNOWN
 936  */
 937 static int
 938 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
 939 {
 940         return 0;
 941 }
 942
 943 /*
 944  * Enable the IrDA function if tty->ldisc.num is N_IRDA.
 945  * In other cases, disable IrDA function.
 946  */
 947 static void bfin_serial_set_ldisc(struct uart_port *port, int ld)
 948 {
 949         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 950         unsigned int val;
 951
 952         switch (ld) {
 953         case N_IRDA:
 954                 val = UART_GET_GCTL(uart);
 955                 val |= (UMOD_IRDA | RPOLC);
 956                 UART_PUT_GCTL(uart, val);
 957                 break;
 958         default:
 959                 val = UART_GET_GCTL(uart);
 960                 val &= ~(UMOD_MASK | RPOLC);
 961                 UART_PUT_GCTL(uart, val);
 962         }
 963 }
 964
 965 static void bfin_serial_reset_irda(struct uart_port *port)
 966 {
 967         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 968         unsigned int val;
 969
 970         val = UART_GET_GCTL(uart);
 971         val &= ~(UMOD_MASK | RPOLC);
 972         UART_PUT_GCTL(uart, val);
 973         SSYNC();
 974         val |= (UMOD_IRDA | RPOLC);
 975         UART_PUT_GCTL(uart, val);
 976         SSYNC();
 977 }
 978
 979 #ifdef CONFIG_CONSOLE_POLL
 980 /* Anomaly notes:
 981  *  05000099 -  Because we only use THRE in poll_put and DR in poll_get,
 982  *              losing other bits of UART_LSR is not a problem here.
 983  */
 984 static void bfin_serial_poll_put_char(struct uart_port *port, unsigned char chr)
 985 {
 986         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 987
 988         while (!(UART_GET_LSR(uart) & THRE))
 989                 cpu_relax();
 990
 991         UART_CLEAR_DLAB(uart);
 992         UART_PUT_CHAR(uart, (unsigned char)chr);
 993 }
 994
 995 static int bfin_serial_poll_get_char(struct uart_port *port)
 996 {
 997         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 998         unsigned char chr;
 999
1000         while (!(UART_GET_LSR(uart) & DR))
1001                 cpu_relax();
1002
1003         UART_CLEAR_DLAB(uart);
1004         chr = UART_GET_CHAR(uart);
1005
1006         return chr;
1007 }
1008 #endif
1009
1010 #if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
1011         defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
1012 static void bfin_kgdboc_port_shutdown(struct uart_port *port)
1013 {
1014         if (kgdboc_break_enabled) {
1015                 kgdboc_break_enabled = 0;
1016                 bfin_serial_shutdown(port);
1017         }
1018 }
1019
1020 static int bfin_kgdboc_port_startup(struct uart_port *port)
1021 {
1022         kgdboc_port_line = port->line;
1023         kgdboc_break_enabled = !bfin_serial_startup(port);
1024         return 0;
1025 }
1026 #endif
1027
1028 static struct uart_ops bfin_serial_pops = {
1029         .tx_empty       = bfin_serial_tx_empty,
1030         .set_mctrl      = bfin_serial_set_mctrl,
1031         .get_mctrl      = bfin_serial_get_mctrl,
1032         .stop_tx        = bfin_serial_stop_tx,
1033         .start_tx       = bfin_serial_start_tx,
1034         .stop_rx        = bfin_serial_stop_rx,
1035         .enable_ms      = bfin_serial_enable_ms,
1036         .break_ctl      = bfin_serial_break_ctl,
1037         .startup        = bfin_serial_startup,
1038         .shutdown       = bfin_serial_shutdown,
1039         .set_termios    = bfin_serial_set_termios,
1040         .set_ldisc      = bfin_serial_set_ldisc,
1041         .type           = bfin_serial_type,
1042         .release_port   = bfin_serial_release_port,
1043         .request_port   = bfin_serial_request_port,
1044         .config_port    = bfin_serial_config_port,
1045         .verify_port    = bfin_serial_verify_port,
1046 #if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
1047         defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
1048         .kgdboc_port_startup    = bfin_kgdboc_port_startup,
1049         .kgdboc_port_shutdown   = bfin_kgdboc_port_shutdown,
1050 #endif
1051 #ifdef CONFIG_CONSOLE_POLL
1052         .poll_put_char  = bfin_serial_poll_put_char,
1053         .poll_get_char  = bfin_serial_poll_get_char,
1054 #endif
1055 };
1056
1057 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) || defined(CONFIG_EARLY_PRINTK)
1058 /*
1059  * If the port was already initialised (eg, by a boot loader),
1060  * try to determine the current setup.
1061  */
1062 static void __init
1063 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
1064                            int *parity, int *bits)
1065 {
1066         unsigned int status;
1067
1068         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
1069         if (status == (ERBFI | ETBEI)) {
1070                 /* ok, the port was enabled */
1071                 u32 lcr, clk;
1072
1073                 lcr = UART_GET_LCR(uart);
1074
1075                 *parity = 'n';
1076                 if (lcr & PEN) {
1077                         if (lcr & EPS)
1078                                 *parity = 'e';
1079                         else
1080                                 *parity = 'o';
1081                 }
1082                 *bits = ((lcr & WLS_MASK) >> WLS_OFFSET) + 5;
1083
1084                 /* Set DLAB in LCR to Access CLK */
1085                 UART_SET_DLAB(uart);
1086
1087                 clk = UART_GET_CLK(uart);
1088
1089                 /* Clear DLAB in LCR to Access THR RBR IER */
1090                 UART_CLEAR_DLAB(uart);
1091
1092                 *baud = get_sclk() / (16*clk);
1093         }
1094         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __func__, *baud, *parity, *bits);
1095 }
1096
1097 static struct uart_driver bfin_serial_reg;
1098
1099 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
1100 {
1101         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
1102         while (!(UART_GET_LSR(uart) & THRE))
1103                 barrier();
1104         UART_PUT_CHAR(uart, ch);
1105 }
1106
1107 #endif /* defined (CONFIG_SERIAL_BFIN_CONSOLE) ||
1108                  defined (CONFIG_EARLY_PRINTK) */
1109
1110 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
1111 #define CLASS_BFIN_CONSOLE      "bfin-console"
1112 /*
1113  * Interrupts are disabled on entering
1114  */
1115 static void
1116 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
1117 {
1118         struct bfin_serial_port *uart = bfin_serial_ports[co->index];
1119         unsigned long flags;
1120
1121         spin_lock_irqsave(&uart->port.lock, flags);
1122         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
1123         spin_unlock_irqrestore(&uart->port.lock, flags);
1124
1125 }
1126
1127 static int __init
1128 bfin_serial_console_setup(struct console *co, char *options)
1129 {
1130         struct bfin_serial_port *uart;
1131         int baud = 57600;
1132         int bits = 8;
1133         int parity = 'n';
1134 # if defined(CONFIG_SERIAL_BFIN_CTSRTS) || \
1135         defined(CONFIG_SERIAL_BFIN_HARD_CTSRTS)
1136         int flow = 'r';
1137 # else
1138         int flow = 'n';
1139 # endif
1140
1141         /*
1142          * Check whether an invalid uart number has been specified, and
1143          * if so, search for the first available port that does have
1144          * console support.
1145          */
1146         if (co->index < 0 || co->index >= BFIN_UART_NR_PORTS)
1147                 return -ENODEV;
1148
1149         uart = bfin_serial_ports[co->index];
1150         if (!uart)
1151                 return -ENODEV;
1152
1153         if (options)
1154                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1155         else
1156                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
1157
1158         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
1159 }
1160
1161 static struct console bfin_serial_console = {
1162         .name           = BFIN_SERIAL_DEV_NAME,
1163         .write          = bfin_serial_console_write,
1164         .device         = uart_console_device,
1165         .setup          = bfin_serial_console_setup,
1166         .flags          = CON_PRINTBUFFER,
1167         .index          = -1,
1168         .data           = &bfin_serial_reg,
1169 };
1170 #define BFIN_SERIAL_CONSOLE     (&bfin_serial_console)
1171 #else
1172 #define BFIN_SERIAL_CONSOLE     NULL
1173 #endif /* CONFIG_SERIAL_BFIN_CONSOLE */
1174
1175 #ifdef  CONFIG_EARLY_PRINTK
1176 static struct bfin_serial_port bfin_earlyprintk_port;
1177 #define CLASS_BFIN_EARLYPRINTK  "bfin-earlyprintk"
1178
1179 /*
1180  * Interrupts are disabled on entering
1181  */
1182 static void
1183 bfin_earlyprintk_console_write(struct console *co, const char *s, unsigned int count)
1184 {
1185         unsigned long flags;
1186
1187         if (bfin_earlyprintk_port.port.line != co->index)
1188                 return;
1189
1190         spin_lock_irqsave(&bfin_earlyprintk_port.port.lock, flags);
1191         uart_console_write(&bfin_earlyprintk_port.port, s, count,
1192                 bfin_serial_console_putchar);
1193         spin_unlock_irqrestore(&bfin_earlyprintk_port.port.lock, flags);
1194 }
1195
1196 /*
1197  * This should have a .setup or .early_setup in it, but then things get called
1198  * without the command line options, and the baud rate gets messed up - so
1199  * don't let the common infrastructure play with things. (see calls to setup
1200  * & earlysetup in ./kernel/printk.c:register_console()
1201  */
1202 static struct __initdata console bfin_early_serial_console = {
1203         .name = "early_BFuart",
1204         .write = bfin_earlyprintk_console_write,
1205         .device = uart_console_device,
1206         .flags = CON_PRINTBUFFER,
1207         .index = -1,
1208         .data  = &bfin_serial_reg,
1209 };
1210 #endif
1211
1212 static struct uart_driver bfin_serial_reg = {
1213         .owner                  = THIS_MODULE,
1214         .driver_name            = DRIVER_NAME,
1215         .dev_name               = BFIN_SERIAL_DEV_NAME,
1216         .major                  = BFIN_SERIAL_MAJOR,
1217         .minor                  = BFIN_SERIAL_MINOR,
1218         .nr                     = BFIN_UART_NR_PORTS,
1219         .cons                   = BFIN_SERIAL_CONSOLE,
1220 };
1221
1222 static int bfin_serial_suspend(struct platform_device *pdev, pm_message_t state)
1223 {
1224         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
1225
1226         return uart_suspend_port(&bfin_serial_reg, &uart->port);
1227 }
1228
1229 static int bfin_serial_resume(struct platform_device *pdev)
1230 {
1231         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
1232
1233         return uart_resume_port(&bfin_serial_reg, &uart->port);
1234 }
1235
1236 static int bfin_serial_probe(struct platform_device *pdev)
1237 {
1238         struct resource *res;
1239         struct bfin_serial_port *uart = NULL;
1240         int ret = 0;
1241
1242         if (pdev->id < 0 || pdev->id >= BFIN_UART_NR_PORTS) {
1243                 dev_err(&pdev->dev, "Wrong bfin uart platform device id.\n");
1244                 return -ENOENT;
1245         }
1246
1247         if (bfin_serial_ports[pdev->id] == NULL) {
1248
1249                 uart = kzalloc(sizeof(*uart), GFP_KERNEL);
1250                 if (!uart) {
1251                         dev_err(&pdev->dev,
1252                                 "fail to malloc bfin_serial_port\n");
1253                         return -ENOMEM;
1254                 }
1255                 bfin_serial_ports[pdev->id] = uart;
1256
1257 #ifdef CONFIG_EARLY_PRINTK
1258                 if (!(bfin_earlyprintk_port.port.membase
1259                         && bfin_earlyprintk_port.port.line == pdev->id)) {
1260                         /*
1261                          * If the peripheral PINs of current port is allocated
1262                          * in earlyprintk probe stage, don't do it again.
1263                          */
1264 #endif
1265                 ret = peripheral_request_list(
1266                         (unsigned short *)pdev->dev.platform_data, DRIVER_NAME);
1267                 if (ret) {
1268                         dev_err(&pdev->dev,
1269                                 "fail to request bfin serial peripherals\n");
1270                         goto out_error_free_mem;
1271                 }
1272 #ifdef CONFIG_EARLY_PRINTK
1273                 }
1274 #endif
1275
1276                 spin_lock_init(&uart->port.lock);
1277                 uart->port.uartclk   = get_sclk();
1278                 uart->port.fifosize  = BFIN_UART_TX_FIFO_SIZE;
1279                 uart->port.ops       = &bfin_serial_pops;
1280                 uart->port.line      = pdev->id;
1281                 uart->port.iotype    = UPIO_MEM;
1282                 uart->port.flags     = UPF_BOOT_AUTOCONF;
1283
1284                 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1285                 if (res == NULL) {
1286                         dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
1287                         ret = -ENOENT;
1288                         goto out_error_free_peripherals;
1289                 }
1290
1291                 uart->port.membase = ioremap(res->start, resource_size(res));
1292                 if (!uart->port.membase) {
1293                         dev_err(&pdev->dev, "Cannot map uart IO\n");
1294                         ret = -ENXIO;
1295                         goto out_error_free_peripherals;
1296                 }
1297                 uart->port.mapbase = res->start;
1298
1299                 uart->tx_irq = platform_get_irq(pdev, 0);
1300                 if (uart->tx_irq < 0) {
1301                         dev_err(&pdev->dev, "No uart TX IRQ specified\n");
1302                         ret = -ENOENT;
1303                         goto out_error_unmap;
1304                 }
1305
1306                 uart->rx_irq = platform_get_irq(pdev, 1);
1307                 if (uart->rx_irq < 0) {
1308                         dev_err(&pdev->dev, "No uart RX IRQ specified\n");
1309                         ret = -ENOENT;
1310                         goto out_error_unmap;
1311                 }
1312                 uart->port.irq = uart->rx_irq;
1313
1314                 uart->status_irq = platform_get_irq(pdev, 2);
1315                 if (uart->status_irq < 0) {
1316                         dev_err(&pdev->dev, "No uart status IRQ specified\n");
1317                         ret = -ENOENT;
1318                         goto out_error_unmap;
1319                 }
1320
1321 #ifdef CONFIG_SERIAL_BFIN_DMA
1322                 spin_lock_init(&uart->rx_lock);
1323                 uart->tx_done       = 1;
1324                 uart->tx_count      = 0;
1325
1326                 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1327                 if (res == NULL) {
1328                         dev_err(&pdev->dev, "No uart TX DMA channel specified\n");
1329                         ret = -ENOENT;
1330                         goto out_error_unmap;
1331                 }
1332                 uart->tx_dma_channel = res->start;
1333
1334                 res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1335                 if (res == NULL) {
1336                         dev_err(&pdev->dev, "No uart RX DMA channel specified\n");
1337                         ret = -ENOENT;
1338                         goto out_error_unmap;
1339                 }
1340                 uart->rx_dma_channel = res->start;
1341
1342                 init_timer(&(uart->rx_dma_timer));
1343 #endif
1344
1345 #if defined(CONFIG_SERIAL_BFIN_CTSRTS) || \
1346         defined(CONFIG_SERIAL_BFIN_HARD_CTSRTS)
1347                 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
1348                 if (res == NULL)
1349                         uart->cts_pin = -1;
1350                 else {
1351                         uart->cts_pin = res->start;
1352 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1353                         uart->port.flags |= ASYNC_CTS_FLOW;
1354 #endif
1355                 }
1356
1357                 res = platform_get_resource(pdev, IORESOURCE_IO, 1);
1358                 if (res == NULL)
1359                         uart->rts_pin = -1;
1360                 else
1361                         uart->rts_pin = res->start;
1362 #endif
1363         }
1364
1365 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
1366         if (!is_early_platform_device(pdev)) {
1367 #endif
1368                 uart = bfin_serial_ports[pdev->id];
1369                 uart->port.dev = &pdev->dev;
1370                 dev_set_drvdata(&pdev->dev, uart);
1371                 ret = uart_add_one_port(&bfin_serial_reg, &uart->port);
1372 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
1373         }
1374 #endif
1375
1376         if (!ret)
1377                 return 0;
1378
1379         if (uart) {
1380 out_error_unmap:
1381                 iounmap(uart->port.membase);
1382 out_error_free_peripherals:
1383                 peripheral_free_list(
1384                         (unsigned short *)pdev->dev.platform_data);
1385 out_error_free_mem:
1386                 kfree(uart);
1387                 bfin_serial_ports[pdev->id] = NULL;
1388         }
1389
1390         return ret;
1391 }
1392
1393 static int __devexit bfin_serial_remove(struct platform_device *pdev)
1394 {
1395         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
1396
1397         dev_set_drvdata(&pdev->dev, NULL);
1398
1399         if (uart) {
1400                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
1401                 iounmap(uart->port.membase);
1402                 peripheral_free_list(
1403                         (unsigned short *)pdev->dev.platform_data);
1404                 kfree(uart);
1405                 bfin_serial_ports[pdev->id] = NULL;
1406         }
1407
1408         return 0;
1409 }
1410
1411 static struct platform_driver bfin_serial_driver = {
1412         .probe          = bfin_serial_probe,
1413         .remove         = __devexit_p(bfin_serial_remove),
1414         .suspend        = bfin_serial_suspend,
1415         .resume         = bfin_serial_resume,
1416         .driver         = {
1417                 .name   = DRIVER_NAME,
1418                 .owner  = THIS_MODULE,
1419         },
1420 };
1421
1422 #if defined(CONFIG_SERIAL_BFIN_CONSOLE)
1423 static __initdata struct early_platform_driver early_bfin_serial_driver = {
1424         .class_str = CLASS_BFIN_CONSOLE,
1425         .pdrv = &bfin_serial_driver,
1426         .requested_id = EARLY_PLATFORM_ID_UNSET,
1427 };
1428
1429 static int __init bfin_serial_rs_console_init(void)
1430 {
1431         early_platform_driver_register(&early_bfin_serial_driver, DRIVER_NAME);
1432
1433         early_platform_driver_probe(CLASS_BFIN_CONSOLE, BFIN_UART_NR_PORTS, 0);
1434
1435         register_console(&bfin_serial_console);
1436
1437         return 0;
1438 }
1439 console_initcall(bfin_serial_rs_console_init);
1440 #endif
1441
1442 #ifdef CONFIG_EARLY_PRINTK
1443 /*
1444  * Memory can't be allocated dynamically during earlyprink init stage.
1445  * So, do individual probe for earlyprink with a static uart port variable.
1446  */
1447 static int bfin_earlyprintk_probe(struct platform_device *pdev)
1448 {
1449         struct resource *res;
1450         int ret;
1451
1452         if (pdev->id < 0 || pdev->id >= BFIN_UART_NR_PORTS) {
1453                 dev_err(&pdev->dev, "Wrong earlyprintk platform device id.\n");
1454                 return -ENOENT;
1455         }
1456
1457         ret = peripheral_request_list(
1458                 (unsigned short *)pdev->dev.platform_data, DRIVER_NAME);
1459         if (ret) {
1460                 dev_err(&pdev->dev,
1461                                 "fail to request bfin serial peripherals\n");
1462                         return ret;
1463         }
1464
1465         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1466         if (res == NULL) {
1467                 dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
1468                 ret = -ENOENT;
1469                 goto out_error_free_peripherals;
1470         }
1471
1472         bfin_earlyprintk_port.port.membase = ioremap(res->start,
1473                                                      resource_size(res));
1474         if (!bfin_earlyprintk_port.port.membase) {
1475                 dev_err(&pdev->dev, "Cannot map uart IO\n");
1476                 ret = -ENXIO;
1477                 goto out_error_free_peripherals;
1478         }
1479         bfin_earlyprintk_port.port.mapbase = res->start;
1480         bfin_earlyprintk_port.port.line = pdev->id;
1481         bfin_earlyprintk_port.port.uartclk = get_sclk();
1482         bfin_earlyprintk_port.port.fifosize  = BFIN_UART_TX_FIFO_SIZE;
1483         spin_lock_init(&bfin_earlyprintk_port.port.lock);
1484
1485         return 0;
1486
1487 out_error_free_peripherals:
1488         peripheral_free_list(
1489                 (unsigned short *)pdev->dev.platform_data);
1490
1491         return ret;
1492 }
1493
1494 static struct platform_driver bfin_earlyprintk_driver = {
1495         .probe          = bfin_earlyprintk_probe,
1496         .driver         = {
1497                 .name   = DRIVER_NAME,
1498                 .owner  = THIS_MODULE,
1499         },
1500 };
1501
1502 static __initdata struct early_platform_driver early_bfin_earlyprintk_driver = {
1503         .class_str = CLASS_BFIN_EARLYPRINTK,
1504         .pdrv = &bfin_earlyprintk_driver,
1505         .requested_id = EARLY_PLATFORM_ID_UNSET,
1506 };
1507
1508 struct console __init *bfin_earlyserial_init(unsigned int port,
1509                                                 unsigned int cflag)
1510 {
1511         struct ktermios t;
1512         char port_name[20];
1513
1514         if (port < 0 || port >= BFIN_UART_NR_PORTS)
1515                 return NULL;
1516
1517         /*
1518          * Only probe resource of the given port in earlyprintk boot arg.
1519          * The expected port id should be indicated in port name string.
1520          */
1521         snprintf(port_name, 20, DRIVER_NAME ".%d", port);
1522         early_platform_driver_register(&early_bfin_earlyprintk_driver,
1523                 port_name);
1524         early_platform_driver_probe(CLASS_BFIN_EARLYPRINTK, 1, 0);
1525
1526         if (!bfin_earlyprintk_port.port.membase)
1527                 return NULL;
1528
1529 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
1530         /*
1531          * If we are using early serial, don't let the normal console rewind
1532          * log buffer, since that causes things to be printed multiple times
1533          */
1534         bfin_serial_console.flags &= ~CON_PRINTBUFFER;
1535 #endif
1536
1537         bfin_early_serial_console.index = port;
1538         t.c_cflag = cflag;
1539         t.c_iflag = 0;
1540         t.c_oflag = 0;
1541         t.c_lflag = ICANON;
1542         t.c_line = port;
1543         bfin_serial_set_termios(&bfin_earlyprintk_port.port, &t, &t);
1544
1545         return &bfin_early_serial_console;
1546 }
1547 #endif /* CONFIG_EARLY_PRINTK */
1548
1549 static int __init bfin_serial_init(void)
1550 {
1551         int ret;
1552
1553         pr_info("Blackfin serial driver\n");
1554
1555         ret = uart_register_driver(&bfin_serial_reg);
1556         if (ret) {
1557                 pr_err("failed to register %s:%d\n",
1558                         bfin_serial_reg.driver_name, ret);
1559         }
1560
1561         ret = platform_driver_register(&bfin_serial_driver);
1562         if (ret) {
1563                 pr_err("fail to register bfin uart\n");
1564                 uart_unregister_driver(&bfin_serial_reg);
1565         }
1566
1567         return ret;
1568 }
1569
1570 static void __exit bfin_serial_exit(void)
1571 {
1572         platform_driver_unregister(&bfin_serial_driver);
1573         uart_unregister_driver(&bfin_serial_reg);
1574 }
1575
1576
1577 module_init(bfin_serial_init);
1578 module_exit(bfin_serial_exit);
1579
1580 MODULE_AUTHOR("Sonic Zhang, Aubrey Li");
1581 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1582 MODULE_LICENSE("GPL");
1583 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);
1584 MODULE_ALIAS("platform:bfin-uart");