drivers/serial/mpc52xx_uart.c

   1 /*
   2  * drivers/serial/mpc52xx_uart.c
   3  *
   4  * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
   5  *
   6  * FIXME According to the usermanual the status bits in the status register
   7  * are only updated when the peripherals access the FIFO and not when the
   8  * CPU access them. So since we use this bits to know when we stop writing
   9  * and reading, they may not be updated in-time and a race condition may
  10  * exists. But I haven't be able to prove this and I don't care. But if
  11  * any problem arises, it might worth checking. The TX/RX FIFO Stats
  12  * registers should be used in addition.
  13  * Update: Actually, they seem updated ... At least the bits we use.
  14  *
  15  *
  16  * Maintainer : Sylvain Munaut <tnt@246tNt.com>
  17  *
  18  * Some of the code has been inspired/copied from the 2.4 code written
  19  * by Dale Farnsworth <dfarnsworth@mvista.com>.
  20  *
  21  * Copyright (C) 2004-2005 Sylvain Munaut <tnt@246tNt.com>
  22  * Copyright (C) 2003 MontaVista, Software, Inc.
  23  *
  24  * This file is licensed under the terms of the GNU General Public License
  25  * version 2. This program is licensed "as is" without any warranty of any
  26  * kind, whether express or implied.
  27  */
  28
  29 /* Platform device Usage :
  30  *
  31  * Since PSCs can have multiple function, the correct driver for each one
  32  * is selected by calling mpc52xx_match_psc_function(...). The function
  33  * handled by this driver is "uart".
  34  *
  35  * The driver init all necessary registers to place the PSC in uart mode without
  36  * DCD. However, the pin multiplexing aren't changed and should be set either
  37  * by the bootloader or in the platform init code.
  38  *
  39  * The idx field must be equal to the PSC index ( e.g. 0 for PSC1, 1 for PSC2,
  40  * and so on). So the PSC1 is mapped to /dev/ttyPSC0, PSC2 to /dev/ttyPSC1 and
  41  * so on. But be warned, it's an ABSOLUTE REQUIREMENT ! This is needed mainly
  42  * fpr the console code : without this 1:1 mapping, at early boot time, when we
  43  * are parsing the kernel args console=ttyPSC?, we wouldn't know which PSC it
  44  * will be mapped to.
  45  */
  46
  47 #include <linux/platform_device.h>
  48 #include <linux/module.h>
  49 #include <linux/tty.h>
  50 #include <linux/serial.h>
  51 #include <linux/sysrq.h>
  52 #include <linux/console.h>
  53
  54 #include <asm/delay.h>
  55 #include <asm/io.h>
  56
  57 #include <asm/mpc52xx.h>
  58 #include <asm/mpc52xx_psc.h>
  59
  60 #if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  61 #define SUPPORT_SYSRQ
  62 #endif
  63
  64 #include <linux/serial_core.h>
  65
  66
  67 /* We've been assigned a range on the "Low-density serial ports" major */
  68 #define SERIAL_PSC_MAJOR        204
  69 #define SERIAL_PSC_MINOR        148
  70
  71
  72 #define ISR_PASS_LIMIT 256      /* Max number of iteration in the interrupt */
  73
  74
  75 static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
  76         /* Rem: - We use the read_status_mask as a shadow of
  77          *        psc->mpc52xx_psc_imr
  78          *      - It's important that is array is all zero on start as we
  79          *        use it to know if it's initialized or not ! If it's not sure
  80          *        it's cleared, then a memset(...,0,...) should be added to
  81          *        the console_init
  82          */
  83
  84 #define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
  85
  86
  87 /* Forward declaration of the interruption handling routine */
  88 static irqreturn_t mpc52xx_uart_int(int irq,void *dev_id,struct pt_regs *regs);
  89
  90
  91 /* Simple macro to test if a port is console or not. This one is taken
  92  * for serial_core.c and maybe should be moved to serial_core.h ? */
  93 #ifdef CONFIG_SERIAL_CORE_CONSOLE
  94 #define uart_console(port)      ((port)->cons && (port)->cons->index == (port)->line)
  95 #else
  96 #define uart_console(port)      (0)
  97 #endif
  98
  99
 100 /* ======================================================================== */
 101 /* UART operations                                                          */
 102 /* ======================================================================== */
 103
 104 static unsigned int
 105 mpc52xx_uart_tx_empty(struct uart_port *port)
 106 {
 107         int status = in_be16(&PSC(port)->mpc52xx_psc_status);
 108         return (status & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0;
 109 }
 110
 111 static void
 112 mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
 113 {
 114         /* Not implemented */
 115 }
 116
 117 static unsigned int
 118 mpc52xx_uart_get_mctrl(struct uart_port *port)
 119 {
 120         /* Not implemented */
 121         return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 122 }
 123
 124 static void
 125 mpc52xx_uart_stop_tx(struct uart_port *port)
 126 {
 127         /* port->lock taken by caller */
 128         port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
 129         out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
 130 }
 131
 132 static void
 133 mpc52xx_uart_start_tx(struct uart_port *port)
 134 {
 135         /* port->lock taken by caller */
 136         port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
 137         out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
 138 }
 139
 140 static void
 141 mpc52xx_uart_send_xchar(struct uart_port *port, char ch)
 142 {
 143         unsigned long flags;
 144         spin_lock_irqsave(&port->lock, flags);
 145
 146         port->x_char = ch;
 147         if (ch) {
 148                 /* Make sure tx interrupts are on */
 149                 /* Truly necessary ??? They should be anyway */
 150                 port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
 151                 out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
 152         }
 153
 154         spin_unlock_irqrestore(&port->lock, flags);
 155 }
 156
 157 static void
 158 mpc52xx_uart_stop_rx(struct uart_port *port)
 159 {
 160         /* port->lock taken by caller */
 161         port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
 162         out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
 163 }
 164
 165 static void
 166 mpc52xx_uart_enable_ms(struct uart_port *port)
 167 {
 168         /* Not implemented */
 169 }
 170
 171 static void
 172 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
 173 {
 174         unsigned long flags;
 175         spin_lock_irqsave(&port->lock, flags);
 176
 177         if ( ctl == -1 )
 178                 out_8(&PSC(port)->command,MPC52xx_PSC_START_BRK);
 179         else
 180                 out_8(&PSC(port)->command,MPC52xx_PSC_STOP_BRK);
 181
 182         spin_unlock_irqrestore(&port->lock, flags);
 183 }
 184
 185 static int
 186 mpc52xx_uart_startup(struct uart_port *port)
 187 {
 188         struct mpc52xx_psc __iomem *psc = PSC(port);
 189         int ret;
 190
 191         /* Request IRQ */
 192         ret = request_irq(port->irq, mpc52xx_uart_int,
 193                 IRQF_DISABLED | IRQF_SAMPLE_RANDOM, "mpc52xx_psc_uart", port);
 194         if (ret)
 195                 return ret;
 196
 197         /* Reset/activate the port, clear and enable interrupts */
 198         out_8(&psc->command,MPC52xx_PSC_RST_RX);
 199         out_8(&psc->command,MPC52xx_PSC_RST_TX);
 200
 201         out_be32(&psc->sicr,0); /* UART mode DCD ignored */
 202
 203         out_be16(&psc->mpc52xx_psc_clock_select, 0xdd00); /* /16 prescaler on */
 204
 205         out_8(&psc->rfcntl, 0x00);
 206         out_be16(&psc->rfalarm, 0x1ff);
 207         out_8(&psc->tfcntl, 0x07);
 208         out_be16(&psc->tfalarm, 0x80);
 209
 210         port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
 211         out_be16(&psc->mpc52xx_psc_imr,port->read_status_mask);
 212
 213         out_8(&psc->command,MPC52xx_PSC_TX_ENABLE);
 214         out_8(&psc->command,MPC52xx_PSC_RX_ENABLE);
 215
 216         return 0;
 217 }
 218
 219 static void
 220 mpc52xx_uart_shutdown(struct uart_port *port)
 221 {
 222         struct mpc52xx_psc __iomem *psc = PSC(port);
 223
 224         /* Shut down the port, interrupt and all */
 225         out_8(&psc->command,MPC52xx_PSC_RST_RX);
 226         out_8(&psc->command,MPC52xx_PSC_RST_TX);
 227
 228         port->read_status_mask = 0;
 229         out_be16(&psc->mpc52xx_psc_imr,port->read_status_mask);
 230
 231         /* Release interrupt */
 232         free_irq(port->irq, port);
 233 }
 234
 235 static void
 236 mpc52xx_uart_set_termios(struct uart_port *port, struct termios *new,
 237                          struct termios *old)
 238 {
 239         struct mpc52xx_psc __iomem *psc = PSC(port);
 240         unsigned long flags;
 241         unsigned char mr1, mr2;
 242         unsigned short ctr;
 243         unsigned int j, baud, quot;
 244
 245         /* Prepare what we're gonna write */
 246         mr1 = 0;
 247
 248         switch (new->c_cflag & CSIZE) {
 249                 case CS5:       mr1 |= MPC52xx_PSC_MODE_5_BITS;
 250                                 break;
 251                 case CS6:       mr1 |= MPC52xx_PSC_MODE_6_BITS;
 252                                 break;
 253                 case CS7:       mr1 |= MPC52xx_PSC_MODE_7_BITS;
 254                                 break;
 255                 case CS8:
 256                 default:        mr1 |= MPC52xx_PSC_MODE_8_BITS;
 257         }
 258
 259         if (new->c_cflag & PARENB) {
 260                 mr1 |= (new->c_cflag & PARODD) ?
 261                         MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
 262         } else
 263                 mr1 |= MPC52xx_PSC_MODE_PARNONE;
 264
 265
 266         mr2 = 0;
 267
 268         if (new->c_cflag & CSTOPB)
 269                 mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
 270         else
 271                 mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
 272                         MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
 273                         MPC52xx_PSC_MODE_ONE_STOP;
 274
 275
 276         baud = uart_get_baud_rate(port, new, old, 0, port->uartclk/16);
 277         quot = uart_get_divisor(port, baud);
 278         ctr = quot & 0xffff;
 279
 280         /* Get the lock */
 281         spin_lock_irqsave(&port->lock, flags);
 282
 283         /* Update the per-port timeout */
 284         uart_update_timeout(port, new->c_cflag, baud);
 285
 286         /* Do our best to flush TX & RX, so we don't loose anything */
 287         /* But we don't wait indefinitly ! */
 288         j = 5000000;    /* Maximum wait */
 289         /* FIXME Can't receive chars since set_termios might be called at early
 290          * boot for the console, all stuff is not yet ready to receive at that
 291          * time and that just makes the kernel oops */
 292         /* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
 293         while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP) &&
 294                --j)
 295                 udelay(1);
 296
 297         if (!j)
 298                 printk( KERN_ERR "mpc52xx_uart.c: "
 299                         "Unable to flush RX & TX fifos in-time in set_termios."
 300                         "Some chars may have been lost.\n" );
 301
 302         /* Reset the TX & RX */
 303         out_8(&psc->command,MPC52xx_PSC_RST_RX);
 304         out_8(&psc->command,MPC52xx_PSC_RST_TX);
 305
 306         /* Send new mode settings */
 307         out_8(&psc->command,MPC52xx_PSC_SEL_MODE_REG_1);
 308         out_8(&psc->mode,mr1);
 309         out_8(&psc->mode,mr2);
 310         out_8(&psc->ctur,ctr >> 8);
 311         out_8(&psc->ctlr,ctr & 0xff);
 312
 313         /* Reenable TX & RX */
 314         out_8(&psc->command,MPC52xx_PSC_TX_ENABLE);
 315         out_8(&psc->command,MPC52xx_PSC_RX_ENABLE);
 316
 317         /* We're all set, release the lock */
 318         spin_unlock_irqrestore(&port->lock, flags);
 319 }
 320
 321 static const char *
 322 mpc52xx_uart_type(struct uart_port *port)
 323 {
 324         return port->type == PORT_MPC52xx ? "MPC52xx PSC" : NULL;
 325 }
 326
 327 static void
 328 mpc52xx_uart_release_port(struct uart_port *port)
 329 {
 330         if (port->flags & UPF_IOREMAP) { /* remapped by us ? */
 331                 iounmap(port->membase);
 332                 port->membase = NULL;
 333         }
 334
 335         release_mem_region(port->mapbase, MPC52xx_PSC_SIZE);
 336 }
 337
 338 static int
 339 mpc52xx_uart_request_port(struct uart_port *port)
 340 {
 341         if (port->flags & UPF_IOREMAP) /* Need to remap ? */
 342                 port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE);
 343
 344         if (!port->membase)
 345                 return -EINVAL;
 346
 347         return request_mem_region(port->mapbase, MPC52xx_PSC_SIZE,
 348                         "mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
 349 }
 350
 351 static void
 352 mpc52xx_uart_config_port(struct uart_port *port, int flags)
 353 {
 354         if ( (flags & UART_CONFIG_TYPE) &&
 355              (mpc52xx_uart_request_port(port) == 0) )
 356                 port->type = PORT_MPC52xx;
 357 }
 358
 359 static int
 360 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
 361 {
 362         if ( ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx )
 363                 return -EINVAL;
 364
 365         if ( (ser->irq != port->irq) ||
 366              (ser->io_type != SERIAL_IO_MEM) ||
 367              (ser->baud_base != port->uartclk)  ||
 368              (ser->iomem_base != (void*)port->mapbase) ||
 369              (ser->hub6 != 0 ) )
 370                 return -EINVAL;
 371
 372         return 0;
 373 }
 374
 375
 376 static struct uart_ops mpc52xx_uart_ops = {
 377         .tx_empty       = mpc52xx_uart_tx_empty,
 378         .set_mctrl      = mpc52xx_uart_set_mctrl,
 379         .get_mctrl      = mpc52xx_uart_get_mctrl,
 380         .stop_tx        = mpc52xx_uart_stop_tx,
 381         .start_tx       = mpc52xx_uart_start_tx,
 382         .send_xchar     = mpc52xx_uart_send_xchar,
 383         .stop_rx        = mpc52xx_uart_stop_rx,
 384         .enable_ms      = mpc52xx_uart_enable_ms,
 385         .break_ctl      = mpc52xx_uart_break_ctl,
 386         .startup        = mpc52xx_uart_startup,
 387         .shutdown       = mpc52xx_uart_shutdown,
 388         .set_termios    = mpc52xx_uart_set_termios,
 389 /*      .pm             = mpc52xx_uart_pm,              Not supported yet */
 390 /*      .set_wake       = mpc52xx_uart_set_wake,        Not supported yet */
 391         .type           = mpc52xx_uart_type,
 392         .release_port   = mpc52xx_uart_release_port,
 393         .request_port   = mpc52xx_uart_request_port,
 394         .config_port    = mpc52xx_uart_config_port,
 395         .verify_port    = mpc52xx_uart_verify_port
 396 };
 397
 398
 399 /* ======================================================================== */
 400 /* Interrupt handling                                                       */
 401 /* ======================================================================== */
 402
 403 static inline int
 404 mpc52xx_uart_int_rx_chars(struct uart_port *port, struct pt_regs *regs)
 405 {
 406         struct tty_struct *tty = port->info->tty;
 407         unsigned char ch, flag;
 408         unsigned short status;
 409
 410         /* While we can read, do so ! */
 411         while ( (status = in_be16(&PSC(port)->mpc52xx_psc_status)) &
 412                 MPC52xx_PSC_SR_RXRDY) {
 413
 414                 /* Get the char */
 415                 ch = in_8(&PSC(port)->mpc52xx_psc_buffer_8);
 416
 417                 /* Handle sysreq char */
 418 #ifdef SUPPORT_SYSRQ
 419                 if (uart_handle_sysrq_char(port, ch, regs)) {
 420                         port->sysrq = 0;
 421                         continue;
 422                 }
 423 #endif
 424
 425                 /* Store it */
 426
 427                 flag = TTY_NORMAL;
 428                 port->icount.rx++;
 429
 430                 if ( status & (MPC52xx_PSC_SR_PE |
 431                                MPC52xx_PSC_SR_FE |
 432                                MPC52xx_PSC_SR_RB) ) {
 433
 434                         if (status & MPC52xx_PSC_SR_RB) {
 435                                 flag = TTY_BREAK;
 436                                 uart_handle_break(port);
 437                         } else if (status & MPC52xx_PSC_SR_PE)
 438                                 flag = TTY_PARITY;
 439                         else if (status & MPC52xx_PSC_SR_FE)
 440                                 flag = TTY_FRAME;
 441
 442                         /* Clear error condition */
 443                         out_8(&PSC(port)->command,MPC52xx_PSC_RST_ERR_STAT);
 444
 445                 }
 446                 tty_insert_flip_char(tty, ch, flag);
 447                 if (status & MPC52xx_PSC_SR_OE) {
 448                         /*
 449                          * Overrun is special, since it's
 450                          * reported immediately, and doesn't
 451                          * affect the current character
 452                          */
 453                         tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 454                 }
 455         }
 456
 457         tty_flip_buffer_push(tty);
 458
 459         return in_be16(&PSC(port)->mpc52xx_psc_status) & MPC52xx_PSC_SR_RXRDY;
 460 }
 461
 462 static inline int
 463 mpc52xx_uart_int_tx_chars(struct uart_port *port)
 464 {
 465         struct circ_buf *xmit = &port->info->xmit;
 466
 467         /* Process out of band chars */
 468         if (port->x_char) {
 469                 out_8(&PSC(port)->mpc52xx_psc_buffer_8, port->x_char);
 470                 port->icount.tx++;
 471                 port->x_char = 0;
 472                 return 1;
 473         }
 474
 475         /* Nothing to do ? */
 476         if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
 477                 mpc52xx_uart_stop_tx(port);
 478                 return 0;
 479         }
 480
 481         /* Send chars */
 482         while (in_be16(&PSC(port)->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXRDY) {
 483                 out_8(&PSC(port)->mpc52xx_psc_buffer_8, xmit->buf[xmit->tail]);
 484                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 485                 port->icount.tx++;
 486                 if (uart_circ_empty(xmit))
 487                         break;
 488         }
 489
 490         /* Wake up */
 491         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 492                 uart_write_wakeup(port);
 493
 494         /* Maybe we're done after all */
 495         if (uart_circ_empty(xmit)) {
 496                 mpc52xx_uart_stop_tx(port);
 497                 return 0;
 498         }
 499
 500         return 1;
 501 }
 502
 503 static irqreturn_t
 504 mpc52xx_uart_int(int irq, void *dev_id, struct pt_regs *regs)
 505 {
 506         struct uart_port *port = (struct uart_port *) dev_id;
 507         unsigned long pass = ISR_PASS_LIMIT;
 508         unsigned int keepgoing;
 509         unsigned short status;
 510
 511         if ( irq != port->irq ) {
 512                 printk( KERN_WARNING
 513                         "mpc52xx_uart_int : " \
 514                         "Received wrong int %d. Waiting for %d\n",
 515                        irq, port->irq);
 516                 return IRQ_NONE;
 517         }
 518
 519         spin_lock(&port->lock);
 520
 521         /* While we have stuff to do, we continue */
 522         do {
 523                 /* If we don't find anything to do, we stop */
 524                 keepgoing = 0;
 525
 526                 /* Read status */
 527                 status = in_be16(&PSC(port)->mpc52xx_psc_isr);
 528                 status &= port->read_status_mask;
 529
 530                 /* Do we need to receive chars ? */
 531                 /* For this RX interrupts must be on and some chars waiting */
 532                 if ( status & MPC52xx_PSC_IMR_RXRDY )
 533                         keepgoing |= mpc52xx_uart_int_rx_chars(port, regs);
 534
 535                 /* Do we need to send chars ? */
 536                 /* For this, TX must be ready and TX interrupt enabled */
 537                 if ( status & MPC52xx_PSC_IMR_TXRDY )
 538                         keepgoing |= mpc52xx_uart_int_tx_chars(port);
 539
 540                 /* Limit number of iteration */
 541                 if ( !(--pass) )
 542                         keepgoing = 0;
 543
 544         } while (keepgoing);
 545
 546         spin_unlock(&port->lock);
 547
 548         return IRQ_HANDLED;
 549 }
 550
 551
 552 /* ======================================================================== */
 553 /* Console ( if applicable )                                                */
 554 /* ======================================================================== */
 555
 556 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
 557
 558 static void __init
 559 mpc52xx_console_get_options(struct uart_port *port,
 560                             int *baud, int *parity, int *bits, int *flow)
 561 {
 562         struct mpc52xx_psc __iomem *psc = PSC(port);
 563         unsigned char mr1;
 564
 565         /* Read the mode registers */
 566         out_8(&psc->command,MPC52xx_PSC_SEL_MODE_REG_1);
 567         mr1 = in_8(&psc->mode);
 568
 569         /* CT{U,L}R are write-only ! */
 570         *baud = __res.bi_baudrate ?
 571                 __res.bi_baudrate : CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
 572
 573         /* Parse them */
 574         switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
 575                 case MPC52xx_PSC_MODE_5_BITS:   *bits = 5; break;
 576                 case MPC52xx_PSC_MODE_6_BITS:   *bits = 6; break;
 577                 case MPC52xx_PSC_MODE_7_BITS:   *bits = 7; break;
 578                 case MPC52xx_PSC_MODE_8_BITS:
 579                 default:                        *bits = 8;
 580         }
 581
 582         if (mr1 & MPC52xx_PSC_MODE_PARNONE)
 583                 *parity = 'n';
 584         else
 585                 *parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
 586 }
 587
 588 static void
 589 mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
 590 {
 591         struct uart_port *port = &mpc52xx_uart_ports[co->index];
 592         struct mpc52xx_psc __iomem *psc = PSC(port);
 593         unsigned int i, j;
 594
 595         /* Disable interrupts */
 596         out_be16(&psc->mpc52xx_psc_imr, 0);
 597
 598         /* Wait the TX buffer to be empty */
 599         j = 5000000;    /* Maximum wait */
 600         while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP) &&
 601                --j)
 602                 udelay(1);
 603
 604         /* Write all the chars */
 605         for (i = 0; i < count; i++, s++) {
 606                 /* Line return handling */
 607                 if (*s == '\n')
 608                         out_8(&psc->mpc52xx_psc_buffer_8, '\r');
 609
 610                 /* Send the char */
 611                 out_8(&psc->mpc52xx_psc_buffer_8, *s);
 612
 613                 /* Wait the TX buffer to be empty */
 614                 j = 20000;      /* Maximum wait */
 615                 while (!(in_be16(&psc->mpc52xx_psc_status) &
 616                          MPC52xx_PSC_SR_TXEMP) && --j)
 617                         udelay(1);
 618         }
 619
 620         /* Restore interrupt state */
 621         out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
 622 }
 623
 624 static int __init
 625 mpc52xx_console_setup(struct console *co, char *options)
 626 {
 627         struct uart_port *port = &mpc52xx_uart_ports[co->index];
 628
 629         int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
 630         int bits = 8;
 631         int parity = 'n';
 632         int flow = 'n';
 633
 634         if (co->index < 0 || co->index >= MPC52xx_PSC_MAXNUM)
 635                 return -EINVAL;
 636
 637         /* Basic port init. Needed since we use some uart_??? func before
 638          * real init for early access */
 639         spin_lock_init(&port->lock);
 640         port->uartclk   = __res.bi_ipbfreq / 2; /* Look at CTLR doc */
 641         port->ops       = &mpc52xx_uart_ops;
 642         port->mapbase   = MPC52xx_PA(MPC52xx_PSCx_OFFSET(co->index+1));
 643
 644         /* We ioremap ourself */
 645         port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE);
 646         if (port->membase == NULL)
 647                 return -EINVAL;
 648
 649         /* Setup the port parameters accoding to options */
 650         if (options)
 651                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 652         else
 653                 mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
 654
 655         return uart_set_options(port, co, baud, parity, bits, flow);
 656 }
 657
 658
 659 static struct uart_driver mpc52xx_uart_driver;
 660
 661 static struct console mpc52xx_console = {
 662         .name   = "ttyPSC",
 663         .write  = mpc52xx_console_write,
 664         .device = uart_console_device,
 665         .setup  = mpc52xx_console_setup,
 666         .flags  = CON_PRINTBUFFER,
 667         .index  = -1,   /* Specified on the cmdline (e.g. console=ttyPSC0 ) */
 668         .data   = &mpc52xx_uart_driver,
 669 };
 670
 671
 672 static int __init
 673 mpc52xx_console_init(void)
 674 {
 675         register_console(&mpc52xx_console);
 676         return 0;
 677 }
 678
 679 console_initcall(mpc52xx_console_init);
 680
 681 #define MPC52xx_PSC_CONSOLE &mpc52xx_console
 682 #else
 683 #define MPC52xx_PSC_CONSOLE NULL
 684 #endif
 685
 686
 687 /* ======================================================================== */
 688 /* UART Driver                                                              */
 689 /* ======================================================================== */
 690
 691 static struct uart_driver mpc52xx_uart_driver = {
 692         .owner          = THIS_MODULE,
 693         .driver_name    = "mpc52xx_psc_uart",
 694         .dev_name       = "ttyPSC",
 695         .major          = SERIAL_PSC_MAJOR,
 696         .minor          = SERIAL_PSC_MINOR,
 697         .nr             = MPC52xx_PSC_MAXNUM,
 698         .cons           = MPC52xx_PSC_CONSOLE,
 699 };
 700
 701
 702 /* ======================================================================== */
 703 /* Platform Driver                                                          */
 704 /* ======================================================================== */
 705
 706 static int __devinit
 707 mpc52xx_uart_probe(struct platform_device *dev)
 708 {
 709         struct resource *res = dev->resource;
 710
 711         struct uart_port *port = NULL;
 712         int i, idx, ret;
 713
 714         /* Check validity & presence */
 715         idx = dev->id;
 716         if (idx < 0 || idx >= MPC52xx_PSC_MAXNUM)
 717                 return -EINVAL;
 718
 719         if (!mpc52xx_match_psc_function(idx,"uart"))
 720                 return -ENODEV;
 721
 722         /* Init the port structure */
 723         port = &mpc52xx_uart_ports[idx];
 724
 725         memset(port, 0x00, sizeof(struct uart_port));
 726
 727         spin_lock_init(&port->lock);
 728         port->uartclk   = __res.bi_ipbfreq / 2; /* Look at CTLR doc */
 729         port->fifosize  = 512;
 730         port->iotype    = UPIO_MEM;
 731         port->flags     = UPF_BOOT_AUTOCONF |
 732                           ( uart_console(port) ? 0 : UPF_IOREMAP );
 733         port->line      = idx;
 734         port->ops       = &mpc52xx_uart_ops;
 735
 736         /* Search for IRQ and mapbase */
 737         for (i=0 ; i<dev->num_resources ; i++, res++) {
 738                 if (res->flags & IORESOURCE_MEM)
 739                         port->mapbase = res->start;
 740                 else if (res->flags & IORESOURCE_IRQ)
 741                         port->irq = res->start;
 742         }
 743         if (!port->irq || !port->mapbase)
 744                 return -EINVAL;
 745
 746         /* Add the port to the uart sub-system */
 747         ret = uart_add_one_port(&mpc52xx_uart_driver, port);
 748         if (!ret)
 749                 platform_set_drvdata(dev, (void*)port);
 750
 751         return ret;
 752 }
 753
 754 static int
 755 mpc52xx_uart_remove(struct platform_device *dev)
 756 {
 757         struct uart_port *port = (struct uart_port *) platform_get_drvdata(dev);
 758
 759         platform_set_drvdata(dev, NULL);
 760
 761         if (port)
 762                 uart_remove_one_port(&mpc52xx_uart_driver, port);
 763
 764         return 0;
 765 }
 766
 767 #ifdef CONFIG_PM
 768 static int
 769 mpc52xx_uart_suspend(struct platform_device *dev, pm_message_t state)
 770 {
 771         struct uart_port *port = (struct uart_port *) platform_get_drvdata(dev);
 772
 773         if (sport)
 774                 uart_suspend_port(&mpc52xx_uart_driver, port);
 775
 776         return 0;
 777 }
 778
 779 static int
 780 mpc52xx_uart_resume(struct platform_device *dev)
 781 {
 782         struct uart_port *port = (struct uart_port *) platform_get_drvdata(dev);
 783
 784         if (port)
 785                 uart_resume_port(&mpc52xx_uart_driver, port);
 786
 787         return 0;
 788 }
 789 #endif
 790
 791 static struct platform_driver mpc52xx_uart_platform_driver = {
 792         .probe          = mpc52xx_uart_probe,
 793         .remove         = mpc52xx_uart_remove,
 794 #ifdef CONFIG_PM
 795         .suspend        = mpc52xx_uart_suspend,
 796         .resume         = mpc52xx_uart_resume,
 797 #endif
 798         .driver         = {
 799                 .name   = "mpc52xx-psc",
 800         },
 801 };
 802
 803
 804 /* ======================================================================== */
 805 /* Module                                                                   */
 806 /* ======================================================================== */
 807
 808 static int __init
 809 mpc52xx_uart_init(void)
 810 {
 811         int ret;
 812
 813         printk(KERN_INFO "Serial: MPC52xx PSC driver\n");
 814
 815         ret = uart_register_driver(&mpc52xx_uart_driver);
 816         if (ret == 0) {
 817                 ret = platform_driver_register(&mpc52xx_uart_platform_driver);
 818                 if (ret)
 819                         uart_unregister_driver(&mpc52xx_uart_driver);
 820         }
 821
 822         return ret;
 823 }
 824
 825 static void __exit
 826 mpc52xx_uart_exit(void)
 827 {
 828         platform_driver_unregister(&mpc52xx_uart_platform_driver);
 829         uart_unregister_driver(&mpc52xx_uart_driver);
 830 }
 831
 832
 833 module_init(mpc52xx_uart_init);
 834 module_exit(mpc52xx_uart_exit);
 835
 836 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
 837 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
 838 MODULE_LICENSE("GPL");