linux/drivers/tty/serial/lpc32xx_hs.c
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   1/*
   2 * High Speed Serial Ports on NXP LPC32xx SoC
   3 *
   4 * Authors: Kevin Wells <kevin.wells@nxp.com>
   5 *          Roland Stigge <stigge@antcom.de>
   6 *
   7 * Copyright (C) 2010 NXP Semiconductors
   8 * Copyright (C) 2012 Roland Stigge
   9 *
  10 * This program is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License as published by
  12 * the Free Software Foundation; either version 2 of the License, or
  13 * (at your option) any later version.
  14 *
  15 * This program is distributed in the hope that it will be useful,
  16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 * GNU General Public License for more details.
  19 */
  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/tty.h>
  27#include <linux/tty_flip.h>
  28#include <linux/serial_core.h>
  29#include <linux/serial.h>
  30#include <linux/platform_device.h>
  31#include <linux/delay.h>
  32#include <linux/nmi.h>
  33#include <linux/io.h>
  34#include <linux/irq.h>
  35#include <linux/gpio.h>
  36#include <linux/of.h>
  37#include <mach/platform.h>
  38#include <mach/hardware.h>
  39
  40/*
  41 * High Speed UART register offsets
  42 */
  43#define LPC32XX_HSUART_FIFO(x)                  ((x) + 0x00)
  44#define LPC32XX_HSUART_LEVEL(x)                 ((x) + 0x04)
  45#define LPC32XX_HSUART_IIR(x)                   ((x) + 0x08)
  46#define LPC32XX_HSUART_CTRL(x)                  ((x) + 0x0C)
  47#define LPC32XX_HSUART_RATE(x)                  ((x) + 0x10)
  48
  49#define LPC32XX_HSU_BREAK_DATA                  (1 << 10)
  50#define LPC32XX_HSU_ERROR_DATA                  (1 << 9)
  51#define LPC32XX_HSU_RX_EMPTY                    (1 << 8)
  52
  53#define LPC32XX_HSU_TX_LEV(n)                   (((n) >> 8) & 0xFF)
  54#define LPC32XX_HSU_RX_LEV(n)                   ((n) & 0xFF)
  55
  56#define LPC32XX_HSU_TX_INT_SET                  (1 << 6)
  57#define LPC32XX_HSU_RX_OE_INT                   (1 << 5)
  58#define LPC32XX_HSU_BRK_INT                     (1 << 4)
  59#define LPC32XX_HSU_FE_INT                      (1 << 3)
  60#define LPC32XX_HSU_RX_TIMEOUT_INT              (1 << 2)
  61#define LPC32XX_HSU_RX_TRIG_INT                 (1 << 1)
  62#define LPC32XX_HSU_TX_INT                      (1 << 0)
  63
  64#define LPC32XX_HSU_HRTS_INV                    (1 << 21)
  65#define LPC32XX_HSU_HRTS_TRIG_8B                (0x0 << 19)
  66#define LPC32XX_HSU_HRTS_TRIG_16B               (0x1 << 19)
  67#define LPC32XX_HSU_HRTS_TRIG_32B               (0x2 << 19)
  68#define LPC32XX_HSU_HRTS_TRIG_48B               (0x3 << 19)
  69#define LPC32XX_HSU_HRTS_EN                     (1 << 18)
  70#define LPC32XX_HSU_TMO_DISABLED                (0x0 << 16)
  71#define LPC32XX_HSU_TMO_INACT_4B                (0x1 << 16)
  72#define LPC32XX_HSU_TMO_INACT_8B                (0x2 << 16)
  73#define LPC32XX_HSU_TMO_INACT_16B               (0x3 << 16)
  74#define LPC32XX_HSU_HCTS_INV                    (1 << 15)
  75#define LPC32XX_HSU_HCTS_EN                     (1 << 14)
  76#define LPC32XX_HSU_OFFSET(n)                   ((n) << 9)
  77#define LPC32XX_HSU_BREAK                       (1 << 8)
  78#define LPC32XX_HSU_ERR_INT_EN                  (1 << 7)
  79#define LPC32XX_HSU_RX_INT_EN                   (1 << 6)
  80#define LPC32XX_HSU_TX_INT_EN                   (1 << 5)
  81#define LPC32XX_HSU_RX_TL1B                     (0x0 << 2)
  82#define LPC32XX_HSU_RX_TL4B                     (0x1 << 2)
  83#define LPC32XX_HSU_RX_TL8B                     (0x2 << 2)
  84#define LPC32XX_HSU_RX_TL16B                    (0x3 << 2)
  85#define LPC32XX_HSU_RX_TL32B                    (0x4 << 2)
  86#define LPC32XX_HSU_RX_TL48B                    (0x5 << 2)
  87#define LPC32XX_HSU_TX_TLEMPTY                  (0x0 << 0)
  88#define LPC32XX_HSU_TX_TL0B                     (0x0 << 0)
  89#define LPC32XX_HSU_TX_TL4B                     (0x1 << 0)
  90#define LPC32XX_HSU_TX_TL8B                     (0x2 << 0)
  91#define LPC32XX_HSU_TX_TL16B                    (0x3 << 0)
  92
  93#define MODNAME "lpc32xx_hsuart"
  94
  95struct lpc32xx_hsuart_port {
  96        struct uart_port port;
  97};
  98
  99#define FIFO_READ_LIMIT 128
 100#define MAX_PORTS 3
 101#define LPC32XX_TTY_NAME "ttyTX"
 102static struct lpc32xx_hsuart_port lpc32xx_hs_ports[MAX_PORTS];
 103
 104#ifdef CONFIG_SERIAL_HS_LPC32XX_CONSOLE
 105static void wait_for_xmit_empty(struct uart_port *port)
 106{
 107        unsigned int timeout = 10000;
 108
 109        do {
 110                if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
 111                                                        port->membase))) == 0)
 112                        break;
 113                if (--timeout == 0)
 114                        break;
 115                udelay(1);
 116        } while (1);
 117}
 118
 119static void wait_for_xmit_ready(struct uart_port *port)
 120{
 121        unsigned int timeout = 10000;
 122
 123        while (1) {
 124                if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
 125                                                        port->membase))) < 32)
 126                        break;
 127                if (--timeout == 0)
 128                        break;
 129                udelay(1);
 130        }
 131}
 132
 133static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
 134{
 135        wait_for_xmit_ready(port);
 136        writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
 137}
 138
 139static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
 140                                         unsigned int count)
 141{
 142        struct lpc32xx_hsuart_port *up = &lpc32xx_hs_ports[co->index];
 143        unsigned long flags;
 144        int locked = 1;
 145
 146        touch_nmi_watchdog();
 147        local_irq_save(flags);
 148        if (up->port.sysrq)
 149                locked = 0;
 150        else if (oops_in_progress)
 151                locked = spin_trylock(&up->port.lock);
 152        else
 153                spin_lock(&up->port.lock);
 154
 155        uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
 156        wait_for_xmit_empty(&up->port);
 157
 158        if (locked)
 159                spin_unlock(&up->port.lock);
 160        local_irq_restore(flags);
 161}
 162
 163static int __init lpc32xx_hsuart_console_setup(struct console *co,
 164                                               char *options)
 165{
 166        struct uart_port *port;
 167        int baud = 115200;
 168        int bits = 8;
 169        int parity = 'n';
 170        int flow = 'n';
 171
 172        if (co->index >= MAX_PORTS)
 173                co->index = 0;
 174
 175        port = &lpc32xx_hs_ports[co->index].port;
 176        if (!port->membase)
 177                return -ENODEV;
 178
 179        if (options)
 180                uart_parse_options(options, &baud, &parity, &bits, &flow);
 181
 182        return uart_set_options(port, co, baud, parity, bits, flow);
 183}
 184
 185static struct uart_driver lpc32xx_hsuart_reg;
 186static struct console lpc32xx_hsuart_console = {
 187        .name           = LPC32XX_TTY_NAME,
 188        .write          = lpc32xx_hsuart_console_write,
 189        .device         = uart_console_device,
 190        .setup          = lpc32xx_hsuart_console_setup,
 191        .flags          = CON_PRINTBUFFER,
 192        .index          = -1,
 193        .data           = &lpc32xx_hsuart_reg,
 194};
 195
 196static int __init lpc32xx_hsuart_console_init(void)
 197{
 198        register_console(&lpc32xx_hsuart_console);
 199        return 0;
 200}
 201console_initcall(lpc32xx_hsuart_console_init);
 202
 203#define LPC32XX_HSUART_CONSOLE (&lpc32xx_hsuart_console)
 204#else
 205#define LPC32XX_HSUART_CONSOLE NULL
 206#endif
 207
 208static struct uart_driver lpc32xx_hs_reg = {
 209        .owner          = THIS_MODULE,
 210        .driver_name    = MODNAME,
 211        .dev_name       = LPC32XX_TTY_NAME,
 212        .nr             = MAX_PORTS,
 213        .cons           = LPC32XX_HSUART_CONSOLE,
 214};
 215static int uarts_registered;
 216
 217static unsigned int __serial_get_clock_div(unsigned long uartclk,
 218                                           unsigned long rate)
 219{
 220        u32 div, goodrate, hsu_rate, l_hsu_rate, comprate;
 221        u32 rate_diff;
 222
 223        /* Find the closest divider to get the desired clock rate */
 224        div = uartclk / rate;
 225        goodrate = hsu_rate = (div / 14) - 1;
 226        if (hsu_rate != 0)
 227                hsu_rate--;
 228
 229        /* Tweak divider */
 230        l_hsu_rate = hsu_rate + 3;
 231        rate_diff = 0xFFFFFFFF;
 232
 233        while (hsu_rate < l_hsu_rate) {
 234                comprate = uartclk / ((hsu_rate + 1) * 14);
 235                if (abs(comprate - rate) < rate_diff) {
 236                        goodrate = hsu_rate;
 237                        rate_diff = abs(comprate - rate);
 238                }
 239
 240                hsu_rate++;
 241        }
 242        if (hsu_rate > 0xFF)
 243                hsu_rate = 0xFF;
 244
 245        return goodrate;
 246}
 247
 248static void __serial_uart_flush(struct uart_port *port)
 249{
 250        u32 tmp;
 251        int cnt = 0;
 252
 253        while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
 254               (cnt++ < FIFO_READ_LIMIT))
 255                tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 256}
 257
 258static void __serial_lpc32xx_rx(struct uart_port *port)
 259{
 260        struct tty_port *tport = &port->state->port;
 261        unsigned int tmp, flag;
 262
 263        /* Read data from FIFO and push into terminal */
 264        tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 265        while (!(tmp & LPC32XX_HSU_RX_EMPTY)) {
 266                flag = TTY_NORMAL;
 267                port->icount.rx++;
 268
 269                if (tmp & LPC32XX_HSU_ERROR_DATA) {
 270                        /* Framing error */
 271                        writel(LPC32XX_HSU_FE_INT,
 272                               LPC32XX_HSUART_IIR(port->membase));
 273                        port->icount.frame++;
 274                        flag = TTY_FRAME;
 275                        tty_insert_flip_char(tport, 0, TTY_FRAME);
 276                }
 277
 278                tty_insert_flip_char(tport, (tmp & 0xFF), flag);
 279
 280                tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 281        }
 282
 283        spin_unlock(&port->lock);
 284        tty_flip_buffer_push(tport);
 285        spin_lock(&port->lock);
 286}
 287
 288static void __serial_lpc32xx_tx(struct uart_port *port)
 289{
 290        struct circ_buf *xmit = &port->state->xmit;
 291        unsigned int tmp;
 292
 293        if (port->x_char) {
 294                writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
 295                port->icount.tx++;
 296                port->x_char = 0;
 297                return;
 298        }
 299
 300        if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 301                goto exit_tx;
 302
 303        /* Transfer data */
 304        while (LPC32XX_HSU_TX_LEV(readl(
 305                LPC32XX_HSUART_LEVEL(port->membase))) < 64) {
 306                writel((u32) xmit->buf[xmit->tail],
 307                       LPC32XX_HSUART_FIFO(port->membase));
 308                xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 309                port->icount.tx++;
 310                if (uart_circ_empty(xmit))
 311                        break;
 312        }
 313
 314        if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 315                uart_write_wakeup(port);
 316
 317exit_tx:
 318        if (uart_circ_empty(xmit)) {
 319                tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 320                tmp &= ~LPC32XX_HSU_TX_INT_EN;
 321                writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 322        }
 323}
 324
 325static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 326{
 327        struct uart_port *port = dev_id;
 328        struct tty_port *tport = &port->state->port;
 329        u32 status;
 330
 331        spin_lock(&port->lock);
 332
 333        /* Read UART status and clear latched interrupts */
 334        status = readl(LPC32XX_HSUART_IIR(port->membase));
 335
 336        if (status & LPC32XX_HSU_BRK_INT) {
 337                /* Break received */
 338                writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
 339                port->icount.brk++;
 340                uart_handle_break(port);
 341        }
 342
 343        /* Framing error */
 344        if (status & LPC32XX_HSU_FE_INT)
 345                writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
 346
 347        if (status & LPC32XX_HSU_RX_OE_INT) {
 348                /* Receive FIFO overrun */
 349                writel(LPC32XX_HSU_RX_OE_INT,
 350                       LPC32XX_HSUART_IIR(port->membase));
 351                port->icount.overrun++;
 352                tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 353                tty_schedule_flip(tport);
 354        }
 355
 356        /* Data received? */
 357        if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
 358                __serial_lpc32xx_rx(port);
 359
 360        /* Transmit data request? */
 361        if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
 362                writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
 363                __serial_lpc32xx_tx(port);
 364        }
 365
 366        spin_unlock(&port->lock);
 367
 368        return IRQ_HANDLED;
 369}
 370
 371/* port->lock is not held.  */
 372static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
 373{
 374        unsigned int ret = 0;
 375
 376        if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
 377                ret = TIOCSER_TEMT;
 378
 379        return ret;
 380}
 381
 382/* port->lock held by caller.  */
 383static void serial_lpc32xx_set_mctrl(struct uart_port *port,
 384                                     unsigned int mctrl)
 385{
 386        /* No signals are supported on HS UARTs */
 387}
 388
 389/* port->lock is held by caller and interrupts are disabled.  */
 390static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
 391{
 392        /* No signals are supported on HS UARTs */
 393        return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 394}
 395
 396/* port->lock held by caller.  */
 397static void serial_lpc32xx_stop_tx(struct uart_port *port)
 398{
 399        u32 tmp;
 400
 401        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 402        tmp &= ~LPC32XX_HSU_TX_INT_EN;
 403        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 404}
 405
 406/* port->lock held by caller.  */
 407static void serial_lpc32xx_start_tx(struct uart_port *port)
 408{
 409        u32 tmp;
 410
 411        __serial_lpc32xx_tx(port);
 412        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 413        tmp |= LPC32XX_HSU_TX_INT_EN;
 414        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 415}
 416
 417/* port->lock held by caller.  */
 418static void serial_lpc32xx_stop_rx(struct uart_port *port)
 419{
 420        u32 tmp;
 421
 422        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 423        tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 424        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 425
 426        writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
 427                LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
 428}
 429
 430/* port->lock is not held.  */
 431static void serial_lpc32xx_break_ctl(struct uart_port *port,
 432                                     int break_state)
 433{
 434        unsigned long flags;
 435        u32 tmp;
 436
 437        spin_lock_irqsave(&port->lock, flags);
 438        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 439        if (break_state != 0)
 440                tmp |= LPC32XX_HSU_BREAK;
 441        else
 442                tmp &= ~LPC32XX_HSU_BREAK;
 443        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 444        spin_unlock_irqrestore(&port->lock, flags);
 445}
 446
 447/* LPC3250 Errata HSUART.1: Hang workaround via loopback mode on inactivity */
 448static void lpc32xx_loopback_set(resource_size_t mapbase, int state)
 449{
 450        int bit;
 451        u32 tmp;
 452
 453        switch (mapbase) {
 454        case LPC32XX_HS_UART1_BASE:
 455                bit = 0;
 456                break;
 457        case LPC32XX_HS_UART2_BASE:
 458                bit = 1;
 459                break;
 460        case LPC32XX_HS_UART7_BASE:
 461                bit = 6;
 462                break;
 463        default:
 464                WARN(1, "lpc32xx_hs: Warning: Unknown port at %08x\n", mapbase);
 465                return;
 466        }
 467
 468        tmp = readl(LPC32XX_UARTCTL_CLOOP);
 469        if (state)
 470                tmp |= (1 << bit);
 471        else
 472                tmp &= ~(1 << bit);
 473        writel(tmp, LPC32XX_UARTCTL_CLOOP);
 474}
 475
 476/* port->lock is not held.  */
 477static int serial_lpc32xx_startup(struct uart_port *port)
 478{
 479        int retval;
 480        unsigned long flags;
 481        u32 tmp;
 482
 483        spin_lock_irqsave(&port->lock, flags);
 484
 485        __serial_uart_flush(port);
 486
 487        writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 488                LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 489               LPC32XX_HSUART_IIR(port->membase));
 490
 491        writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 492
 493        /*
 494         * Set receiver timeout, HSU offset of 20, no break, no interrupts,
 495         * and default FIFO trigger levels
 496         */
 497        tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 498                LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 499        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 500
 501        lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
 502
 503        spin_unlock_irqrestore(&port->lock, flags);
 504
 505        retval = request_irq(port->irq, serial_lpc32xx_interrupt,
 506                             0, MODNAME, port);
 507        if (!retval)
 508                writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
 509                       LPC32XX_HSUART_CTRL(port->membase));
 510
 511        return retval;
 512}
 513
 514/* port->lock is not held.  */
 515static void serial_lpc32xx_shutdown(struct uart_port *port)
 516{
 517        u32 tmp;
 518        unsigned long flags;
 519
 520        spin_lock_irqsave(&port->lock, flags);
 521
 522        tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 523                LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 524        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 525
 526        lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
 527
 528        spin_unlock_irqrestore(&port->lock, flags);
 529
 530        free_irq(port->irq, port);
 531}
 532
 533/* port->lock is not held.  */
 534static void serial_lpc32xx_set_termios(struct uart_port *port,
 535                                       struct ktermios *termios,
 536                                       struct ktermios *old)
 537{
 538        unsigned long flags;
 539        unsigned int baud, quot;
 540        u32 tmp;
 541
 542        /* Always 8-bit, no parity, 1 stop bit */
 543        termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
 544        termios->c_cflag |= CS8;
 545
 546        termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
 547
 548        baud = uart_get_baud_rate(port, termios, old, 0,
 549                                  port->uartclk / 14);
 550
 551        quot = __serial_get_clock_div(port->uartclk, baud);
 552
 553        spin_lock_irqsave(&port->lock, flags);
 554
 555        /* Ignore characters? */
 556        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 557        if ((termios->c_cflag & CREAD) == 0)
 558                tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 559        else
 560                tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
 561        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 562
 563        writel(quot, LPC32XX_HSUART_RATE(port->membase));
 564
 565        uart_update_timeout(port, termios->c_cflag, baud);
 566
 567        spin_unlock_irqrestore(&port->lock, flags);
 568
 569        /* Don't rewrite B0 */
 570        if (tty_termios_baud_rate(termios))
 571                tty_termios_encode_baud_rate(termios, baud, baud);
 572}
 573
 574static const char *serial_lpc32xx_type(struct uart_port *port)
 575{
 576        return MODNAME;
 577}
 578
 579static void serial_lpc32xx_release_port(struct uart_port *port)
 580{
 581        if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 582                if (port->flags & UPF_IOREMAP) {
 583                        iounmap(port->membase);
 584                        port->membase = NULL;
 585                }
 586
 587                release_mem_region(port->mapbase, SZ_4K);
 588        }
 589}
 590
 591static int serial_lpc32xx_request_port(struct uart_port *port)
 592{
 593        int ret = -ENODEV;
 594
 595        if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 596                ret = 0;
 597
 598                if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
 599                        ret = -EBUSY;
 600                else if (port->flags & UPF_IOREMAP) {
 601                        port->membase = ioremap(port->mapbase, SZ_4K);
 602                        if (!port->membase) {
 603                                release_mem_region(port->mapbase, SZ_4K);
 604                                ret = -ENOMEM;
 605                        }
 606                }
 607        }
 608
 609        return ret;
 610}
 611
 612static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
 613{
 614        int ret;
 615
 616        ret = serial_lpc32xx_request_port(port);
 617        if (ret < 0)
 618                return;
 619        port->type = PORT_UART00;
 620        port->fifosize = 64;
 621
 622        __serial_uart_flush(port);
 623
 624        writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 625                LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 626               LPC32XX_HSUART_IIR(port->membase));
 627
 628        writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 629
 630        /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
 631           and default FIFO trigger levels */
 632        writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 633               LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
 634               LPC32XX_HSUART_CTRL(port->membase));
 635}
 636
 637static int serial_lpc32xx_verify_port(struct uart_port *port,
 638                                      struct serial_struct *ser)
 639{
 640        int ret = 0;
 641
 642        if (ser->type != PORT_UART00)
 643                ret = -EINVAL;
 644
 645        return ret;
 646}
 647
 648static struct uart_ops serial_lpc32xx_pops = {
 649        .tx_empty       = serial_lpc32xx_tx_empty,
 650        .set_mctrl      = serial_lpc32xx_set_mctrl,
 651        .get_mctrl      = serial_lpc32xx_get_mctrl,
 652        .stop_tx        = serial_lpc32xx_stop_tx,
 653        .start_tx       = serial_lpc32xx_start_tx,
 654        .stop_rx        = serial_lpc32xx_stop_rx,
 655        .break_ctl      = serial_lpc32xx_break_ctl,
 656        .startup        = serial_lpc32xx_startup,
 657        .shutdown       = serial_lpc32xx_shutdown,
 658        .set_termios    = serial_lpc32xx_set_termios,
 659        .type           = serial_lpc32xx_type,
 660        .release_port   = serial_lpc32xx_release_port,
 661        .request_port   = serial_lpc32xx_request_port,
 662        .config_port    = serial_lpc32xx_config_port,
 663        .verify_port    = serial_lpc32xx_verify_port,
 664};
 665
 666/*
 667 * Register a set of serial devices attached to a platform device
 668 */
 669static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
 670{
 671        struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
 672        int ret = 0;
 673        struct resource *res;
 674
 675        if (uarts_registered >= MAX_PORTS) {
 676                dev_err(&pdev->dev,
 677                        "Error: Number of possible ports exceeded (%d)!\n",
 678                        uarts_registered + 1);
 679                return -ENXIO;
 680        }
 681
 682        memset(p, 0, sizeof(*p));
 683
 684        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 685        if (!res) {
 686                dev_err(&pdev->dev,
 687                        "Error getting mem resource for HS UART port %d\n",
 688                        uarts_registered);
 689                return -ENXIO;
 690        }
 691        p->port.mapbase = res->start;
 692        p->port.membase = NULL;
 693
 694        ret = platform_get_irq(pdev, 0);
 695        if (ret < 0) {
 696                dev_err(&pdev->dev, "Error getting irq for HS UART port %d\n",
 697                        uarts_registered);
 698                return ret;
 699        }
 700        p->port.irq = ret;
 701
 702        p->port.iotype = UPIO_MEM32;
 703        p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
 704        p->port.regshift = 2;
 705        p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
 706        p->port.dev = &pdev->dev;
 707        p->port.ops = &serial_lpc32xx_pops;
 708        p->port.line = uarts_registered++;
 709        spin_lock_init(&p->port.lock);
 710
 711        /* send port to loopback mode by default */
 712        lpc32xx_loopback_set(p->port.mapbase, 1);
 713
 714        ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
 715
 716        platform_set_drvdata(pdev, p);
 717
 718        return ret;
 719}
 720
 721/*
 722 * Remove serial ports registered against a platform device.
 723 */
 724static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
 725{
 726        struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 727
 728        uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
 729
 730        return 0;
 731}
 732
 733
 734#ifdef CONFIG_PM
 735static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
 736                                     pm_message_t state)
 737{
 738        struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 739
 740        uart_suspend_port(&lpc32xx_hs_reg, &p->port);
 741
 742        return 0;
 743}
 744
 745static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
 746{
 747        struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 748
 749        uart_resume_port(&lpc32xx_hs_reg, &p->port);
 750
 751        return 0;
 752}
 753#else
 754#define serial_hs_lpc32xx_suspend       NULL
 755#define serial_hs_lpc32xx_resume        NULL
 756#endif
 757
 758static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
 759        { .compatible = "nxp,lpc3220-hsuart" },
 760        { /* sentinel */ }
 761};
 762
 763MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
 764
 765static struct platform_driver serial_hs_lpc32xx_driver = {
 766        .probe          = serial_hs_lpc32xx_probe,
 767        .remove         = serial_hs_lpc32xx_remove,
 768        .suspend        = serial_hs_lpc32xx_suspend,
 769        .resume         = serial_hs_lpc32xx_resume,
 770        .driver         = {
 771                .name   = MODNAME,
 772                .of_match_table = serial_hs_lpc32xx_dt_ids,
 773        },
 774};
 775
 776static int __init lpc32xx_hsuart_init(void)
 777{
 778        int ret;
 779
 780        ret = uart_register_driver(&lpc32xx_hs_reg);
 781        if (ret)
 782                return ret;
 783
 784        ret = platform_driver_register(&serial_hs_lpc32xx_driver);
 785        if (ret)
 786                uart_unregister_driver(&lpc32xx_hs_reg);
 787
 788        return ret;
 789}
 790
 791static void __exit lpc32xx_hsuart_exit(void)
 792{
 793        platform_driver_unregister(&serial_hs_lpc32xx_driver);
 794        uart_unregister_driver(&lpc32xx_hs_reg);
 795}
 796
 797module_init(lpc32xx_hsuart_init);
 798module_exit(lpc32xx_hsuart_exit);
 799
 800MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
 801MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
 802MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
 803MODULE_LICENSE("GPL");
 804