drivers/tty/serial/pnx8xxx_uart.c

   1 /*
   2  * UART driver for PNX8XXX SoCs
   3  *
   4  * Author: Per Hallsmark per.hallsmark@mvista.com
   5  * Ported to 2.6 kernel by EmbeddedAlley
   6  * Reworked by Vitaly Wool <vitalywool@gmail.com>
   7  *
   8  * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
   9  * Copyright (C) 2000 Deep Blue Solutions Ltd.
  10  *
  11  * This file is licensed under the terms of the GNU General Public License
  12  * version 2. This program is licensed "as is" without any warranty of
  13  * any kind, whether express or implied.
  14  *
  15  */
  16
  17 #if defined(CONFIG_SERIAL_PNX8XXX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  18 #define SUPPORT_SYSRQ
  19 #endif
  20
  21 #include <linux/module.h>
  22 #include <linux/ioport.h>
  23 #include <linux/init.h>
  24 #include <linux/console.h>
  25 #include <linux/sysrq.h>
  26 #include <linux/device.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/tty.h>
  29 #include <linux/tty_flip.h>
  30 #include <linux/serial_core.h>
  31 #include <linux/serial.h>
  32 #include <linux/serial_pnx8xxx.h>
  33
  34 #include <asm/io.h>
  35 #include <asm/irq.h>
  36
  37 /* We'll be using StrongARM sa1100 serial port major/minor */
  38 #define SERIAL_PNX8XXX_MAJOR    204
  39 #define MINOR_START             5
  40
  41 #define NR_PORTS                2
  42
  43 #define PNX8XXX_ISR_PASS_LIMIT  256
  44
  45 /*
  46  * Convert from ignore_status_mask or read_status_mask to FIFO
  47  * and interrupt status bits
  48  */
  49 #define SM_TO_FIFO(x)   ((x) >> 10)
  50 #define SM_TO_ISTAT(x)  ((x) & 0x000001ff)
  51 #define FIFO_TO_SM(x)   ((x) << 10)
  52 #define ISTAT_TO_SM(x)  ((x) & 0x000001ff)
  53
  54 /*
  55  * This is the size of our serial port register set.
  56  */
  57 #define UART_PORT_SIZE  0x1000
  58
  59 /*
  60  * This determines how often we check the modem status signals
  61  * for any change.  They generally aren't connected to an IRQ
  62  * so we have to poll them.  We also check immediately before
  63  * filling the TX fifo incase CTS has been dropped.
  64  */
  65 #define MCTRL_TIMEOUT   (250*HZ/1000)
  66
  67 extern struct pnx8xxx_port pnx8xxx_ports[];
  68
  69 static inline int serial_in(struct pnx8xxx_port *sport, int offset)
  70 {
  71         return (__raw_readl(sport->port.membase + offset));
  72 }
  73
  74 static inline void serial_out(struct pnx8xxx_port *sport, int offset, int value)
  75 {
  76         __raw_writel(value, sport->port.membase + offset);
  77 }
  78
  79 /*
  80  * Handle any change of modem status signal since we were last called.
  81  */
  82 static void pnx8xxx_mctrl_check(struct pnx8xxx_port *sport)
  83 {
  84         unsigned int status, changed;
  85
  86         status = sport->port.ops->get_mctrl(&sport->port);
  87         changed = status ^ sport->old_status;
  88
  89         if (changed == 0)
  90                 return;
  91
  92         sport->old_status = status;
  93
  94         if (changed & TIOCM_RI)
  95                 sport->port.icount.rng++;
  96         if (changed & TIOCM_DSR)
  97                 sport->port.icount.dsr++;
  98         if (changed & TIOCM_CAR)
  99                 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
 100         if (changed & TIOCM_CTS)
 101                 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
 102
 103         wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
 104 }
 105
 106 /*
 107  * This is our per-port timeout handler, for checking the
 108  * modem status signals.
 109  */
 110 static void pnx8xxx_timeout(unsigned long data)
 111 {
 112         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)data;
 113         unsigned long flags;
 114
 115         if (sport->port.state) {
 116                 spin_lock_irqsave(&sport->port.lock, flags);
 117                 pnx8xxx_mctrl_check(sport);
 118                 spin_unlock_irqrestore(&sport->port.lock, flags);
 119
 120                 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
 121         }
 122 }
 123
 124 /*
 125  * interrupts disabled on entry
 126  */
 127 static void pnx8xxx_stop_tx(struct uart_port *port)
 128 {
 129         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 130         u32 ien;
 131
 132         /* Disable TX intr */
 133         ien = serial_in(sport, PNX8XXX_IEN);
 134         serial_out(sport, PNX8XXX_IEN, ien & ~PNX8XXX_UART_INT_ALLTX);
 135
 136         /* Clear all pending TX intr */
 137         serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLTX);
 138 }
 139
 140 /*
 141  * interrupts may not be disabled on entry
 142  */
 143 static void pnx8xxx_start_tx(struct uart_port *port)
 144 {
 145         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 146         u32 ien;
 147
 148         /* Clear all pending TX intr */
 149         serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLTX);
 150
 151         /* Enable TX intr */
 152         ien = serial_in(sport, PNX8XXX_IEN);
 153         serial_out(sport, PNX8XXX_IEN, ien | PNX8XXX_UART_INT_ALLTX);
 154 }
 155
 156 /*
 157  * Interrupts enabled
 158  */
 159 static void pnx8xxx_stop_rx(struct uart_port *port)
 160 {
 161         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 162         u32 ien;
 163
 164         /* Disable RX intr */
 165         ien = serial_in(sport, PNX8XXX_IEN);
 166         serial_out(sport, PNX8XXX_IEN, ien & ~PNX8XXX_UART_INT_ALLRX);
 167
 168         /* Clear all pending RX intr */
 169         serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX);
 170 }
 171
 172 /*
 173  * Set the modem control timer to fire immediately.
 174  */
 175 static void pnx8xxx_enable_ms(struct uart_port *port)
 176 {
 177         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 178
 179         mod_timer(&sport->timer, jiffies);
 180 }
 181
 182 static void pnx8xxx_rx_chars(struct pnx8xxx_port *sport)
 183 {
 184         unsigned int status, ch, flg;
 185
 186         status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
 187                  ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
 188         while (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFIFO)) {
 189                 ch = serial_in(sport, PNX8XXX_FIFO) & 0xff;
 190
 191                 sport->port.icount.rx++;
 192
 193                 flg = TTY_NORMAL;
 194
 195                 /*
 196                  * note that the error handling code is
 197                  * out of the main execution path
 198                  */
 199                 if (status & (FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE |
 200                                         PNX8XXX_UART_FIFO_RXPAR |
 201                                         PNX8XXX_UART_FIFO_RXBRK) |
 202                               ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN))) {
 203                         if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXBRK)) {
 204                                 status &= ~(FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
 205                                         FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR));
 206                                 sport->port.icount.brk++;
 207                                 if (uart_handle_break(&sport->port))
 208                                         goto ignore_char;
 209                         } else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR))
 210                                 sport->port.icount.parity++;
 211                         else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE))
 212                                 sport->port.icount.frame++;
 213                         if (status & ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN))
 214                                 sport->port.icount.overrun++;
 215
 216                         status &= sport->port.read_status_mask;
 217
 218                         if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR))
 219                                 flg = TTY_PARITY;
 220                         else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE))
 221                                 flg = TTY_FRAME;
 222
 223 #ifdef SUPPORT_SYSRQ
 224                         sport->port.sysrq = 0;
 225 #endif
 226                 }
 227
 228                 if (uart_handle_sysrq_char(&sport->port, ch))
 229                         goto ignore_char;
 230
 231                 uart_insert_char(&sport->port, status,
 232                                 ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN), ch, flg);
 233
 234         ignore_char:
 235                 serial_out(sport, PNX8XXX_LCR, serial_in(sport, PNX8XXX_LCR) |
 236                                 PNX8XXX_UART_LCR_RX_NEXT);
 237                 status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
 238                          ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
 239         }
 240
 241         spin_unlock(&sport->port.lock);
 242         tty_flip_buffer_push(&sport->port.state->port);
 243         spin_lock(&sport->port.lock);
 244 }
 245
 246 static void pnx8xxx_tx_chars(struct pnx8xxx_port *sport)
 247 {
 248         struct circ_buf *xmit = &sport->port.state->xmit;
 249
 250         if (sport->port.x_char) {
 251                 serial_out(sport, PNX8XXX_FIFO, sport->port.x_char);
 252                 sport->port.icount.tx++;
 253                 sport->port.x_char = 0;
 254                 return;
 255         }
 256
 257         /*
 258          * Check the modem control lines before
 259          * transmitting anything.
 260          */
 261         pnx8xxx_mctrl_check(sport);
 262
 263         if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
 264                 pnx8xxx_stop_tx(&sport->port);
 265                 return;
 266         }
 267
 268         /*
 269          * TX while bytes available
 270          */
 271         while (((serial_in(sport, PNX8XXX_FIFO) &
 272                                         PNX8XXX_UART_FIFO_TXFIFO) >> 16) < 16) {
 273                 serial_out(sport, PNX8XXX_FIFO, xmit->buf[xmit->tail]);
 274                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 275                 sport->port.icount.tx++;
 276                 if (uart_circ_empty(xmit))
 277                         break;
 278         }
 279
 280         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 281                 uart_write_wakeup(&sport->port);
 282
 283         if (uart_circ_empty(xmit))
 284                 pnx8xxx_stop_tx(&sport->port);
 285 }
 286
 287 static irqreturn_t pnx8xxx_int(int irq, void *dev_id)
 288 {
 289         struct pnx8xxx_port *sport = dev_id;
 290         unsigned int status;
 291
 292         spin_lock(&sport->port.lock);
 293         /* Get the interrupts */
 294         status  = serial_in(sport, PNX8XXX_ISTAT) & serial_in(sport, PNX8XXX_IEN);
 295
 296         /* Byte or break signal received */
 297         if (status & (PNX8XXX_UART_INT_RX | PNX8XXX_UART_INT_BREAK))
 298                 pnx8xxx_rx_chars(sport);
 299
 300         /* TX holding register empty - transmit a byte */
 301         if (status & PNX8XXX_UART_INT_TX)
 302                 pnx8xxx_tx_chars(sport);
 303
 304         /* Clear the ISTAT register */
 305         serial_out(sport, PNX8XXX_ICLR, status);
 306
 307         spin_unlock(&sport->port.lock);
 308         return IRQ_HANDLED;
 309 }
 310
 311 /*
 312  * Return TIOCSER_TEMT when transmitter is not busy.
 313  */
 314 static unsigned int pnx8xxx_tx_empty(struct uart_port *port)
 315 {
 316         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 317
 318         return serial_in(sport, PNX8XXX_FIFO) & PNX8XXX_UART_FIFO_TXFIFO_STA ? 0 : TIOCSER_TEMT;
 319 }
 320
 321 static unsigned int pnx8xxx_get_mctrl(struct uart_port *port)
 322 {
 323         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 324         unsigned int mctrl = TIOCM_DSR;
 325         unsigned int msr;
 326
 327         /* REVISIT */
 328
 329         msr = serial_in(sport, PNX8XXX_MCR);
 330
 331         mctrl |= msr & PNX8XXX_UART_MCR_CTS ? TIOCM_CTS : 0;
 332         mctrl |= msr & PNX8XXX_UART_MCR_DCD ? TIOCM_CAR : 0;
 333
 334         return mctrl;
 335 }
 336
 337 static void pnx8xxx_set_mctrl(struct uart_port *port, unsigned int mctrl)
 338 {
 339 #if     0       /* FIXME */
 340         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 341         unsigned int msr;
 342 #endif
 343 }
 344
 345 /*
 346  * Interrupts always disabled.
 347  */
 348 static void pnx8xxx_break_ctl(struct uart_port *port, int break_state)
 349 {
 350         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 351         unsigned long flags;
 352         unsigned int lcr;
 353
 354         spin_lock_irqsave(&sport->port.lock, flags);
 355         lcr = serial_in(sport, PNX8XXX_LCR);
 356         if (break_state == -1)
 357                 lcr |= PNX8XXX_UART_LCR_TXBREAK;
 358         else
 359                 lcr &= ~PNX8XXX_UART_LCR_TXBREAK;
 360         serial_out(sport, PNX8XXX_LCR, lcr);
 361         spin_unlock_irqrestore(&sport->port.lock, flags);
 362 }
 363
 364 static int pnx8xxx_startup(struct uart_port *port)
 365 {
 366         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 367         int retval;
 368
 369         /*
 370          * Allocate the IRQ
 371          */
 372         retval = request_irq(sport->port.irq, pnx8xxx_int, 0,
 373                              "pnx8xxx-uart", sport);
 374         if (retval)
 375                 return retval;
 376
 377         /*
 378          * Finally, clear and enable interrupts
 379          */
 380
 381         serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX |
 382                              PNX8XXX_UART_INT_ALLTX);
 383
 384         serial_out(sport, PNX8XXX_IEN, serial_in(sport, PNX8XXX_IEN) |
 385                             PNX8XXX_UART_INT_ALLRX |
 386                             PNX8XXX_UART_INT_ALLTX);
 387
 388         /*
 389          * Enable modem status interrupts
 390          */
 391         spin_lock_irq(&sport->port.lock);
 392         pnx8xxx_enable_ms(&sport->port);
 393         spin_unlock_irq(&sport->port.lock);
 394
 395         return 0;
 396 }
 397
 398 static void pnx8xxx_shutdown(struct uart_port *port)
 399 {
 400         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 401         int lcr;
 402
 403         /*
 404          * Stop our timer.
 405          */
 406         del_timer_sync(&sport->timer);
 407
 408         /*
 409          * Disable all interrupts
 410          */
 411         serial_out(sport, PNX8XXX_IEN, 0);
 412
 413         /*
 414          * Reset the Tx and Rx FIFOS, disable the break condition
 415          */
 416         lcr = serial_in(sport, PNX8XXX_LCR);
 417         lcr &= ~PNX8XXX_UART_LCR_TXBREAK;
 418         lcr |= PNX8XXX_UART_LCR_TX_RST | PNX8XXX_UART_LCR_RX_RST;
 419         serial_out(sport, PNX8XXX_LCR, lcr);
 420
 421         /*
 422          * Clear all interrupts
 423          */
 424         serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX |
 425                              PNX8XXX_UART_INT_ALLTX);
 426
 427         /*
 428          * Free the interrupt
 429          */
 430         free_irq(sport->port.irq, sport);
 431 }
 432
 433 static void
 434 pnx8xxx_set_termios(struct uart_port *port, struct ktermios *termios,
 435                    struct ktermios *old)
 436 {
 437         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 438         unsigned long flags;
 439         unsigned int lcr_fcr, old_ien, baud, quot;
 440         unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
 441
 442         /*
 443          * We only support CS7 and CS8.
 444          */
 445         while ((termios->c_cflag & CSIZE) != CS7 &&
 446                (termios->c_cflag & CSIZE) != CS8) {
 447                 termios->c_cflag &= ~CSIZE;
 448                 termios->c_cflag |= old_csize;
 449                 old_csize = CS8;
 450         }
 451
 452         if ((termios->c_cflag & CSIZE) == CS8)
 453                 lcr_fcr = PNX8XXX_UART_LCR_8BIT;
 454         else
 455                 lcr_fcr = 0;
 456
 457         if (termios->c_cflag & CSTOPB)
 458                 lcr_fcr |= PNX8XXX_UART_LCR_2STOPB;
 459         if (termios->c_cflag & PARENB) {
 460                 lcr_fcr |= PNX8XXX_UART_LCR_PAREN;
 461                 if (!(termios->c_cflag & PARODD))
 462                         lcr_fcr |= PNX8XXX_UART_LCR_PAREVN;
 463         }
 464
 465         /*
 466          * Ask the core to calculate the divisor for us.
 467          */
 468         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
 469         quot = uart_get_divisor(port, baud);
 470
 471         spin_lock_irqsave(&sport->port.lock, flags);
 472
 473         sport->port.read_status_mask = ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN) |
 474                                 ISTAT_TO_SM(PNX8XXX_UART_INT_EMPTY) |
 475                                 ISTAT_TO_SM(PNX8XXX_UART_INT_RX);
 476         if (termios->c_iflag & INPCK)
 477                 sport->port.read_status_mask |=
 478                         FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
 479                         FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR);
 480         if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
 481                 sport->port.read_status_mask |=
 482                         ISTAT_TO_SM(PNX8XXX_UART_INT_BREAK);
 483
 484         /*
 485          * Characters to ignore
 486          */
 487         sport->port.ignore_status_mask = 0;
 488         if (termios->c_iflag & IGNPAR)
 489                 sport->port.ignore_status_mask |=
 490                         FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
 491                         FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR);
 492         if (termios->c_iflag & IGNBRK) {
 493                 sport->port.ignore_status_mask |=
 494                         ISTAT_TO_SM(PNX8XXX_UART_INT_BREAK);
 495                 /*
 496                  * If we're ignoring parity and break indicators,
 497                  * ignore overruns too (for real raw support).
 498                  */
 499                 if (termios->c_iflag & IGNPAR)
 500                         sport->port.ignore_status_mask |=
 501                                 ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN);
 502         }
 503
 504         /*
 505          * ignore all characters if CREAD is not set
 506          */
 507         if ((termios->c_cflag & CREAD) == 0)
 508                 sport->port.ignore_status_mask |=
 509                         ISTAT_TO_SM(PNX8XXX_UART_INT_RX);
 510
 511         del_timer_sync(&sport->timer);
 512
 513         /*
 514          * Update the per-port timeout.
 515          */
 516         uart_update_timeout(port, termios->c_cflag, baud);
 517
 518         /*
 519          * disable interrupts and drain transmitter
 520          */
 521         old_ien = serial_in(sport, PNX8XXX_IEN);
 522         serial_out(sport, PNX8XXX_IEN, old_ien & ~(PNX8XXX_UART_INT_ALLTX |
 523                                         PNX8XXX_UART_INT_ALLRX));
 524
 525         while (serial_in(sport, PNX8XXX_FIFO) & PNX8XXX_UART_FIFO_TXFIFO_STA)
 526                 barrier();
 527
 528         /* then, disable everything */
 529         serial_out(sport, PNX8XXX_IEN, 0);
 530
 531         /* Reset the Rx and Tx FIFOs too */
 532         lcr_fcr |= PNX8XXX_UART_LCR_TX_RST;
 533         lcr_fcr |= PNX8XXX_UART_LCR_RX_RST;
 534
 535         /* set the parity, stop bits and data size */
 536         serial_out(sport, PNX8XXX_LCR, lcr_fcr);
 537
 538         /* set the baud rate */
 539         quot -= 1;
 540         serial_out(sport, PNX8XXX_BAUD, quot);
 541
 542         serial_out(sport, PNX8XXX_ICLR, -1);
 543
 544         serial_out(sport, PNX8XXX_IEN, old_ien);
 545
 546         if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
 547                 pnx8xxx_enable_ms(&sport->port);
 548
 549         spin_unlock_irqrestore(&sport->port.lock, flags);
 550 }
 551
 552 static const char *pnx8xxx_type(struct uart_port *port)
 553 {
 554         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 555
 556         return sport->port.type == PORT_PNX8XXX ? "PNX8XXX" : NULL;
 557 }
 558
 559 /*
 560  * Release the memory region(s) being used by 'port'.
 561  */
 562 static void pnx8xxx_release_port(struct uart_port *port)
 563 {
 564         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 565
 566         release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
 567 }
 568
 569 /*
 570  * Request the memory region(s) being used by 'port'.
 571  */
 572 static int pnx8xxx_request_port(struct uart_port *port)
 573 {
 574         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 575         return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
 576                         "pnx8xxx-uart") != NULL ? 0 : -EBUSY;
 577 }
 578
 579 /*
 580  * Configure/autoconfigure the port.
 581  */
 582 static void pnx8xxx_config_port(struct uart_port *port, int flags)
 583 {
 584         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 585
 586         if (flags & UART_CONFIG_TYPE &&
 587             pnx8xxx_request_port(&sport->port) == 0)
 588                 sport->port.type = PORT_PNX8XXX;
 589 }
 590
 591 /*
 592  * Verify the new serial_struct (for TIOCSSERIAL).
 593  * The only change we allow are to the flags and type, and
 594  * even then only between PORT_PNX8XXX and PORT_UNKNOWN
 595  */
 596 static int
 597 pnx8xxx_verify_port(struct uart_port *port, struct serial_struct *ser)
 598 {
 599         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 600         int ret = 0;
 601
 602         if (ser->type != PORT_UNKNOWN && ser->type != PORT_PNX8XXX)
 603                 ret = -EINVAL;
 604         if (sport->port.irq != ser->irq)
 605                 ret = -EINVAL;
 606         if (ser->io_type != SERIAL_IO_MEM)
 607                 ret = -EINVAL;
 608         if (sport->port.uartclk / 16 != ser->baud_base)
 609                 ret = -EINVAL;
 610         if ((void *)sport->port.mapbase != ser->iomem_base)
 611                 ret = -EINVAL;
 612         if (sport->port.iobase != ser->port)
 613                 ret = -EINVAL;
 614         if (ser->hub6 != 0)
 615                 ret = -EINVAL;
 616         return ret;
 617 }
 618
 619 static struct uart_ops pnx8xxx_pops = {
 620         .tx_empty       = pnx8xxx_tx_empty,
 621         .set_mctrl      = pnx8xxx_set_mctrl,
 622         .get_mctrl      = pnx8xxx_get_mctrl,
 623         .stop_tx        = pnx8xxx_stop_tx,
 624         .start_tx       = pnx8xxx_start_tx,
 625         .stop_rx        = pnx8xxx_stop_rx,
 626         .enable_ms      = pnx8xxx_enable_ms,
 627         .break_ctl      = pnx8xxx_break_ctl,
 628         .startup        = pnx8xxx_startup,
 629         .shutdown       = pnx8xxx_shutdown,
 630         .set_termios    = pnx8xxx_set_termios,
 631         .type           = pnx8xxx_type,
 632         .release_port   = pnx8xxx_release_port,
 633         .request_port   = pnx8xxx_request_port,
 634         .config_port    = pnx8xxx_config_port,
 635         .verify_port    = pnx8xxx_verify_port,
 636 };
 637
 638
 639 /*
 640  * Setup the PNX8XXX serial ports.
 641  *
 642  * Note also that we support "console=ttySx" where "x" is either 0 or 1.
 643  */
 644 static void __init pnx8xxx_init_ports(void)
 645 {
 646         static int first = 1;
 647         int i;
 648
 649         if (!first)
 650                 return;
 651         first = 0;
 652
 653         for (i = 0; i < NR_PORTS; i++) {
 654                 init_timer(&pnx8xxx_ports[i].timer);
 655                 pnx8xxx_ports[i].timer.function = pnx8xxx_timeout;
 656                 pnx8xxx_ports[i].timer.data     = (unsigned long)&pnx8xxx_ports[i];
 657                 pnx8xxx_ports[i].port.ops = &pnx8xxx_pops;
 658         }
 659 }
 660
 661 #ifdef CONFIG_SERIAL_PNX8XXX_CONSOLE
 662
 663 static void pnx8xxx_console_putchar(struct uart_port *port, int ch)
 664 {
 665         struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
 666         int status;
 667
 668         do {
 669                 /* Wait for UART_TX register to empty */
 670                 status = serial_in(sport, PNX8XXX_FIFO);
 671         } while (status & PNX8XXX_UART_FIFO_TXFIFO);
 672         serial_out(sport, PNX8XXX_FIFO, ch);
 673 }
 674
 675 /*
 676  * Interrupts are disabled on entering
 677  */static void
 678 pnx8xxx_console_write(struct console *co, const char *s, unsigned int count)
 679 {
 680         struct pnx8xxx_port *sport = &pnx8xxx_ports[co->index];
 681         unsigned int old_ien, status;
 682
 683         /*
 684          *      First, save IEN and then disable interrupts
 685          */
 686         old_ien = serial_in(sport, PNX8XXX_IEN);
 687         serial_out(sport, PNX8XXX_IEN, old_ien & ~(PNX8XXX_UART_INT_ALLTX |
 688                                         PNX8XXX_UART_INT_ALLRX));
 689
 690         uart_console_write(&sport->port, s, count, pnx8xxx_console_putchar);
 691
 692         /*
 693          *      Finally, wait for transmitter to become empty
 694          *      and restore IEN
 695          */
 696         do {
 697                 /* Wait for UART_TX register to empty */
 698                 status = serial_in(sport, PNX8XXX_FIFO);
 699         } while (status & PNX8XXX_UART_FIFO_TXFIFO);
 700
 701         /* Clear TX and EMPTY interrupt */
 702         serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_TX |
 703                              PNX8XXX_UART_INT_EMPTY);
 704
 705         serial_out(sport, PNX8XXX_IEN, old_ien);
 706 }
 707
 708 static int __init
 709 pnx8xxx_console_setup(struct console *co, char *options)
 710 {
 711         struct pnx8xxx_port *sport;
 712         int baud = 38400;
 713         int bits = 8;
 714         int parity = 'n';
 715         int flow = 'n';
 716
 717         /*
 718          * Check whether an invalid uart number has been specified, and
 719          * if so, search for the first available port that does have
 720          * console support.
 721          */
 722         if (co->index == -1 || co->index >= NR_PORTS)
 723                 co->index = 0;
 724         sport = &pnx8xxx_ports[co->index];
 725
 726         if (options)
 727                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 728
 729         return uart_set_options(&sport->port, co, baud, parity, bits, flow);
 730 }
 731
 732 static struct uart_driver pnx8xxx_reg;
 733 static struct console pnx8xxx_console = {
 734         .name           = "ttyS",
 735         .write          = pnx8xxx_console_write,
 736         .device         = uart_console_device,
 737         .setup          = pnx8xxx_console_setup,
 738         .flags          = CON_PRINTBUFFER,
 739         .index          = -1,
 740         .data           = &pnx8xxx_reg,
 741 };
 742
 743 static int __init pnx8xxx_rs_console_init(void)
 744 {
 745         pnx8xxx_init_ports();
 746         register_console(&pnx8xxx_console);
 747         return 0;
 748 }
 749 console_initcall(pnx8xxx_rs_console_init);
 750
 751 #define PNX8XXX_CONSOLE &pnx8xxx_console
 752 #else
 753 #define PNX8XXX_CONSOLE NULL
 754 #endif
 755
 756 static struct uart_driver pnx8xxx_reg = {
 757         .owner                  = THIS_MODULE,
 758         .driver_name            = "ttyS",
 759         .dev_name               = "ttyS",
 760         .major                  = SERIAL_PNX8XXX_MAJOR,
 761         .minor                  = MINOR_START,
 762         .nr                     = NR_PORTS,
 763         .cons                   = PNX8XXX_CONSOLE,
 764 };
 765
 766 static int pnx8xxx_serial_suspend(struct platform_device *pdev, pm_message_t state)
 767 {
 768         struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
 769
 770         return uart_suspend_port(&pnx8xxx_reg, &sport->port);
 771 }
 772
 773 static int pnx8xxx_serial_resume(struct platform_device *pdev)
 774 {
 775         struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
 776
 777         return uart_resume_port(&pnx8xxx_reg, &sport->port);
 778 }
 779
 780 static int pnx8xxx_serial_probe(struct platform_device *pdev)
 781 {
 782         struct resource *res = pdev->resource;
 783         int i;
 784
 785         for (i = 0; i < pdev->num_resources; i++, res++) {
 786                 if (!(res->flags & IORESOURCE_MEM))
 787                         continue;
 788
 789                 for (i = 0; i < NR_PORTS; i++) {
 790                         if (pnx8xxx_ports[i].port.mapbase != res->start)
 791                                 continue;
 792
 793                         pnx8xxx_ports[i].port.dev = &pdev->dev;
 794                         uart_add_one_port(&pnx8xxx_reg, &pnx8xxx_ports[i].port);
 795                         platform_set_drvdata(pdev, &pnx8xxx_ports[i]);
 796                         break;
 797                 }
 798         }
 799
 800         return 0;
 801 }
 802
 803 static int pnx8xxx_serial_remove(struct platform_device *pdev)
 804 {
 805         struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
 806
 807         if (sport)
 808                 uart_remove_one_port(&pnx8xxx_reg, &sport->port);
 809
 810         return 0;
 811 }
 812
 813 static struct platform_driver pnx8xxx_serial_driver = {
 814         .driver         = {
 815                 .name   = "pnx8xxx-uart",
 816                 .owner  = THIS_MODULE,
 817         },
 818         .probe          = pnx8xxx_serial_probe,
 819         .remove         = pnx8xxx_serial_remove,
 820         .suspend        = pnx8xxx_serial_suspend,
 821         .resume         = pnx8xxx_serial_resume,
 822 };
 823
 824 static int __init pnx8xxx_serial_init(void)
 825 {
 826         int ret;
 827
 828         printk(KERN_INFO "Serial: PNX8XXX driver\n");
 829
 830         pnx8xxx_init_ports();
 831
 832         ret = uart_register_driver(&pnx8xxx_reg);
 833         if (ret == 0) {
 834                 ret = platform_driver_register(&pnx8xxx_serial_driver);
 835                 if (ret)
 836                         uart_unregister_driver(&pnx8xxx_reg);
 837         }
 838         return ret;
 839 }
 840
 841 static void __exit pnx8xxx_serial_exit(void)
 842 {
 843         platform_driver_unregister(&pnx8xxx_serial_driver);
 844         uart_unregister_driver(&pnx8xxx_reg);
 845 }
 846
 847 module_init(pnx8xxx_serial_init);
 848 module_exit(pnx8xxx_serial_exit);
 849
 850 MODULE_AUTHOR("Embedded Alley Solutions, Inc.");
 851 MODULE_DESCRIPTION("PNX8XXX SoCs serial port driver");
 852 MODULE_LICENSE("GPL");
 853 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_PNX8XXX_MAJOR);
 854 MODULE_ALIAS("platform:pnx8xxx-uart");