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 held by caller.  */
 431static void serial_lpc32xx_enable_ms(struct uart_port *port)
 432{
 433        /* Modem status is not supported */
 434}
 435
 436/* port->lock is not held.  */
 437static void serial_lpc32xx_break_ctl(struct uart_port *port,
 438                                     int break_state)
 439{
 440        unsigned long flags;
 441        u32 tmp;
 442
 443        spin_lock_irqsave(&port->lock, flags);
 444        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 445        if (break_state != 0)
 446                tmp |= LPC32XX_HSU_BREAK;
 447        else
 448                tmp &= ~LPC32XX_HSU_BREAK;
 449        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 450        spin_unlock_irqrestore(&port->lock, flags);
 451}
 452
 453/* LPC3250 Errata HSUART.1: Hang workaround via loopback mode on inactivity */
 454static void lpc32xx_loopback_set(resource_size_t mapbase, int state)
 455{
 456        int bit;
 457        u32 tmp;
 458
 459        switch (mapbase) {
 460        case LPC32XX_HS_UART1_BASE:
 461                bit = 0;
 462                break;
 463        case LPC32XX_HS_UART2_BASE:
 464                bit = 1;
 465                break;
 466        case LPC32XX_HS_UART7_BASE:
 467                bit = 6;
 468                break;
 469        default:
 470                WARN(1, "lpc32xx_hs: Warning: Unknown port at %08x\n", mapbase);
 471                return;
 472        }
 473
 474        tmp = readl(LPC32XX_UARTCTL_CLOOP);
 475        if (state)
 476                tmp |= (1 << bit);
 477        else
 478                tmp &= ~(1 << bit);
 479        writel(tmp, LPC32XX_UARTCTL_CLOOP);
 480}
 481
 482/* port->lock is not held.  */
 483static int serial_lpc32xx_startup(struct uart_port *port)
 484{
 485        int retval;
 486        unsigned long flags;
 487        u32 tmp;
 488
 489        spin_lock_irqsave(&port->lock, flags);
 490
 491        __serial_uart_flush(port);
 492
 493        writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 494                LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 495               LPC32XX_HSUART_IIR(port->membase));
 496
 497        writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 498
 499        /*
 500         * Set receiver timeout, HSU offset of 20, no break, no interrupts,
 501         * and default FIFO trigger levels
 502         */
 503        tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 504                LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 505        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 506
 507        lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
 508
 509        spin_unlock_irqrestore(&port->lock, flags);
 510
 511        retval = request_irq(port->irq, serial_lpc32xx_interrupt,
 512                             0, MODNAME, port);
 513        if (!retval)
 514                writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
 515                       LPC32XX_HSUART_CTRL(port->membase));
 516
 517        return retval;
 518}
 519
 520/* port->lock is not held.  */
 521static void serial_lpc32xx_shutdown(struct uart_port *port)
 522{
 523        u32 tmp;
 524        unsigned long flags;
 525
 526        spin_lock_irqsave(&port->lock, flags);
 527
 528        tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 529                LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 530        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 531
 532        lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
 533
 534        spin_unlock_irqrestore(&port->lock, flags);
 535
 536        free_irq(port->irq, port);
 537}
 538
 539/* port->lock is not held.  */
 540static void serial_lpc32xx_set_termios(struct uart_port *port,
 541                                       struct ktermios *termios,
 542                                       struct ktermios *old)
 543{
 544        unsigned long flags;
 545        unsigned int baud, quot;
 546        u32 tmp;
 547
 548        /* Always 8-bit, no parity, 1 stop bit */
 549        termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
 550        termios->c_cflag |= CS8;
 551
 552        termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
 553
 554        baud = uart_get_baud_rate(port, termios, old, 0,
 555                                  port->uartclk / 14);
 556
 557        quot = __serial_get_clock_div(port->uartclk, baud);
 558
 559        spin_lock_irqsave(&port->lock, flags);
 560
 561        /* Ignore characters? */
 562        tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 563        if ((termios->c_cflag & CREAD) == 0)
 564                tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 565        else
 566                tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
 567        writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 568
 569        writel(quot, LPC32XX_HSUART_RATE(port->membase));
 570
 571        uart_update_timeout(port, termios->c_cflag, baud);
 572
 573        spin_unlock_irqrestore(&port->lock, flags);
 574
 575        /* Don't rewrite B0 */
 576        if (tty_termios_baud_rate(termios))
 577                tty_termios_encode_baud_rate(termios, baud, baud);
 578}
 579
 580static const char *serial_lpc32xx_type(struct uart_port *port)
 581{
 582        return MODNAME;
 583}
 584
 585static void serial_lpc32xx_release_port(struct uart_port *port)
 586{
 587        if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 588                if (port->flags & UPF_IOREMAP) {
 589                        iounmap(port->membase);
 590                        port->membase = NULL;
 591                }
 592
 593                release_mem_region(port->mapbase, SZ_4K);
 594        }
 595}
 596
 597static int serial_lpc32xx_request_port(struct uart_port *port)
 598{
 599        int ret = -ENODEV;
 600
 601        if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 602                ret = 0;
 603
 604                if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
 605                        ret = -EBUSY;
 606                else if (port->flags & UPF_IOREMAP) {
 607                        port->membase = ioremap(port->mapbase, SZ_4K);
 608                        if (!port->membase) {
 609                                release_mem_region(port->mapbase, SZ_4K);
 610                                ret = -ENOMEM;
 611                        }
 612                }
 613        }
 614
 615        return ret;
 616}
 617
 618static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
 619{
 620        int ret;
 621
 622        ret = serial_lpc32xx_request_port(port);
 623        if (ret < 0)
 624                return;
 625        port->type = PORT_UART00;
 626        port->fifosize = 64;
 627
 628        __serial_uart_flush(port);
 629
 630        writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 631                LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 632               LPC32XX_HSUART_IIR(port->membase));
 633
 634        writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 635
 636        /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
 637           and default FIFO trigger levels */
 638        writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 639               LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
 640               LPC32XX_HSUART_CTRL(port->membase));
 641}
 642
 643static int serial_lpc32xx_verify_port(struct uart_port *port,
 644                                      struct serial_struct *ser)
 645{
 646        int ret = 0;
 647
 648        if (ser->type != PORT_UART00)
 649                ret = -EINVAL;
 650
 651        return ret;
 652}
 653
 654static struct uart_ops serial_lpc32xx_pops = {
 655        .tx_empty       = serial_lpc32xx_tx_empty,
 656        .set_mctrl      = serial_lpc32xx_set_mctrl,
 657        .get_mctrl      = serial_lpc32xx_get_mctrl,
 658        .stop_tx        = serial_lpc32xx_stop_tx,
 659        .start_tx       = serial_lpc32xx_start_tx,
 660        .stop_rx        = serial_lpc32xx_stop_rx,
 661        .enable_ms      = serial_lpc32xx_enable_ms,
 662        .break_ctl      = serial_lpc32xx_break_ctl,
 663        .startup        = serial_lpc32xx_startup,
 664        .shutdown       = serial_lpc32xx_shutdown,
 665        .set_termios    = serial_lpc32xx_set_termios,
 666        .type           = serial_lpc32xx_type,
 667        .release_port   = serial_lpc32xx_release_port,
 668        .request_port   = serial_lpc32xx_request_port,
 669        .config_port    = serial_lpc32xx_config_port,
 670        .verify_port    = serial_lpc32xx_verify_port,
 671};
 672
 673/*
 674 * Register a set of serial devices attached to a platform device
 675 */
 676static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
 677{
 678        struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
 679        int ret = 0;
 680        struct resource *res;
 681
 682        if (uarts_registered >= MAX_PORTS) {
 683                dev_err(&pdev->dev,
 684                        "Error: Number of possible ports exceeded (%d)!\n",
 685                        uarts_registered + 1);
 686                return -ENXIO;
 687        }
 688
 689        memset(p, 0, sizeof(*p));
 690
 691        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 692        if (!res) {
 693                dev_err(&pdev->dev,
 694                        "Error getting mem resource for HS UART port %d\n",
 695                        uarts_registered);
 696                return -ENXIO;
 697        }
 698        p->port.mapbase = res->start;
 699        p->port.membase = NULL;
 700
 701        p->port.irq = platform_get_irq(pdev, 0);
 702        if (p->port.irq < 0) {
 703                dev_err(&pdev->dev, "Error getting irq for HS UART port %d\n",
 704                        uarts_registered);
 705                return p->port.irq;
 706        }
 707
 708        p->port.iotype = UPIO_MEM32;
 709        p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
 710        p->port.regshift = 2;
 711        p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
 712        p->port.dev = &pdev->dev;
 713        p->port.ops = &serial_lpc32xx_pops;
 714        p->port.line = uarts_registered++;
 715        spin_lock_init(&p->port.lock);
 716
 717        /* send port to loopback mode by default */
 718        lpc32xx_loopback_set(p->port.mapbase, 1);
 719
 720        ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
 721
 722        platform_set_drvdata(pdev, p);
 723
 724        return ret;
 725}
 726
 727/*
 728 * Remove serial ports registered against a platform device.
 729 */
 730static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
 731{
 732        struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 733
 734        uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
 735
 736        return 0;
 737}
 738
 739
 740#ifdef CONFIG_PM
 741static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
 742                                     pm_message_t state)
 743{
 744        struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 745
 746        uart_suspend_port(&lpc32xx_hs_reg, &p->port);
 747
 748        return 0;
 749}
 750
 751static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
 752{
 753        struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 754
 755        uart_resume_port(&lpc32xx_hs_reg, &p->port);
 756
 757        return 0;
 758}
 759#else
 760#define serial_hs_lpc32xx_suspend       NULL
 761#define serial_hs_lpc32xx_resume        NULL
 762#endif
 763
 764static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
 765        { .compatible = "nxp,lpc3220-hsuart" },
 766        { /* sentinel */ }
 767};
 768
 769MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
 770
 771static struct platform_driver serial_hs_lpc32xx_driver = {
 772        .probe          = serial_hs_lpc32xx_probe,
 773        .remove         = serial_hs_lpc32xx_remove,
 774        .suspend        = serial_hs_lpc32xx_suspend,
 775        .resume         = serial_hs_lpc32xx_resume,
 776        .driver         = {
 777                .name   = MODNAME,
 778                .owner  = THIS_MODULE,
 779                .of_match_table = serial_hs_lpc32xx_dt_ids,
 780        },
 781};
 782
 783static int __init lpc32xx_hsuart_init(void)
 784{
 785        int ret;
 786
 787        ret = uart_register_driver(&lpc32xx_hs_reg);
 788        if (ret)
 789                return ret;
 790
 791        ret = platform_driver_register(&serial_hs_lpc32xx_driver);
 792        if (ret)
 793                uart_unregister_driver(&lpc32xx_hs_reg);
 794
 795        return ret;
 796}
 797
 798static void __exit lpc32xx_hsuart_exit(void)
 799{
 800        platform_driver_unregister(&serial_hs_lpc32xx_driver);
 801        uart_unregister_driver(&lpc32xx_hs_reg);
 802}
 803
 804module_init(lpc32xx_hsuart_init);
 805module_exit(lpc32xx_hsuart_exit);
 806
 807MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
 808MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
 809MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
 810MODULE_LICENSE("GPL");
 811