drivers/tty/serial/lpc32xx_hs.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * High Speed Serial Ports on NXP LPC32xx SoC
   4  *
   5  * Authors: Kevin Wells <[email protected]>
   6  *          Roland Stigge <[email protected]>
   7  *
   8  * Copyright (C) 2010 NXP Semiconductors
   9  * Copyright (C) 2012 Roland Stigge
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/ioport.h>
  14 #include <linux/init.h>
  15 #include <linux/console.h>
  16 #include <linux/sysrq.h>
  17 #include <linux/tty.h>
  18 #include <linux/tty_flip.h>
  19 #include <linux/serial_core.h>
  20 #include <linux/serial.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/delay.h>
  23 #include <linux/nmi.h>
  24 #include <linux/io.h>
  25 #include <linux/irq.h>
  26 #include <linux/of.h>
  27 #include <linux/sizes.h>
  28 #include <linux/soc/nxp/lpc32xx-misc.h>
  29
  30 /*
  31  * High Speed UART register offsets
  32  */
  33 #define LPC32XX_HSUART_FIFO(x)                  ((x) + 0x00)
  34 #define LPC32XX_HSUART_LEVEL(x)                 ((x) + 0x04)
  35 #define LPC32XX_HSUART_IIR(x)                   ((x) + 0x08)
  36 #define LPC32XX_HSUART_CTRL(x)                  ((x) + 0x0C)
  37 #define LPC32XX_HSUART_RATE(x)                  ((x) + 0x10)
  38
  39 #define LPC32XX_HSU_BREAK_DATA                  (1 << 10)
  40 #define LPC32XX_HSU_ERROR_DATA                  (1 << 9)
  41 #define LPC32XX_HSU_RX_EMPTY                    (1 << 8)
  42
  43 #define LPC32XX_HSU_TX_LEV(n)                   (((n) >> 8) & 0xFF)
  44 #define LPC32XX_HSU_RX_LEV(n)                   ((n) & 0xFF)
  45
  46 #define LPC32XX_HSU_TX_INT_SET                  (1 << 6)
  47 #define LPC32XX_HSU_RX_OE_INT                   (1 << 5)
  48 #define LPC32XX_HSU_BRK_INT                     (1 << 4)
  49 #define LPC32XX_HSU_FE_INT                      (1 << 3)
  50 #define LPC32XX_HSU_RX_TIMEOUT_INT              (1 << 2)
  51 #define LPC32XX_HSU_RX_TRIG_INT                 (1 << 1)
  52 #define LPC32XX_HSU_TX_INT                      (1 << 0)
  53
  54 #define LPC32XX_HSU_HRTS_INV                    (1 << 21)
  55 #define LPC32XX_HSU_HRTS_TRIG_8B                (0x0 << 19)
  56 #define LPC32XX_HSU_HRTS_TRIG_16B               (0x1 << 19)
  57 #define LPC32XX_HSU_HRTS_TRIG_32B               (0x2 << 19)
  58 #define LPC32XX_HSU_HRTS_TRIG_48B               (0x3 << 19)
  59 #define LPC32XX_HSU_HRTS_EN                     (1 << 18)
  60 #define LPC32XX_HSU_TMO_DISABLED                (0x0 << 16)
  61 #define LPC32XX_HSU_TMO_INACT_4B                (0x1 << 16)
  62 #define LPC32XX_HSU_TMO_INACT_8B                (0x2 << 16)
  63 #define LPC32XX_HSU_TMO_INACT_16B               (0x3 << 16)
  64 #define LPC32XX_HSU_HCTS_INV                    (1 << 15)
  65 #define LPC32XX_HSU_HCTS_EN                     (1 << 14)
  66 #define LPC32XX_HSU_OFFSET(n)                   ((n) << 9)
  67 #define LPC32XX_HSU_BREAK                       (1 << 8)
  68 #define LPC32XX_HSU_ERR_INT_EN                  (1 << 7)
  69 #define LPC32XX_HSU_RX_INT_EN                   (1 << 6)
  70 #define LPC32XX_HSU_TX_INT_EN                   (1 << 5)
  71 #define LPC32XX_HSU_RX_TL1B                     (0x0 << 2)
  72 #define LPC32XX_HSU_RX_TL4B                     (0x1 << 2)
  73 #define LPC32XX_HSU_RX_TL8B                     (0x2 << 2)
  74 #define LPC32XX_HSU_RX_TL16B                    (0x3 << 2)
  75 #define LPC32XX_HSU_RX_TL32B                    (0x4 << 2)
  76 #define LPC32XX_HSU_RX_TL48B                    (0x5 << 2)
  77 #define LPC32XX_HSU_TX_TLEMPTY                  (0x0 << 0)
  78 #define LPC32XX_HSU_TX_TL0B                     (0x0 << 0)
  79 #define LPC32XX_HSU_TX_TL4B                     (0x1 << 0)
  80 #define LPC32XX_HSU_TX_TL8B                     (0x2 << 0)
  81 #define LPC32XX_HSU_TX_TL16B                    (0x3 << 0)
  82
  83 #define LPC32XX_MAIN_OSC_FREQ                   13000000
  84
  85 #define MODNAME "lpc32xx_hsuart"
  86
  87 struct lpc32xx_hsuart_port {
  88         struct uart_port port;
  89 };
  90
  91 #define FIFO_READ_LIMIT 128
  92 #define MAX_PORTS 3
  93 #define LPC32XX_TTY_NAME "ttyTX"
  94 static struct lpc32xx_hsuart_port lpc32xx_hs_ports[MAX_PORTS];
  95
  96 #ifdef CONFIG_SERIAL_HS_LPC32XX_CONSOLE
  97 static void wait_for_xmit_empty(struct uart_port *port)
  98 {
  99         unsigned int timeout = 10000;
 100
 101         do {
 102                 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
 103                                                         port->membase))) == 0)
 104                         break;
 105                 if (--timeout == 0)
 106                         break;
 107                 udelay(1);
 108         } while (1);
 109 }
 110
 111 static void wait_for_xmit_ready(struct uart_port *port)
 112 {
 113         unsigned int timeout = 10000;
 114
 115         while (1) {
 116                 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
 117                                                         port->membase))) < 32)
 118                         break;
 119                 if (--timeout == 0)
 120                         break;
 121                 udelay(1);
 122         }
 123 }
 124
 125 static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
 126 {
 127         wait_for_xmit_ready(port);
 128         writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
 129 }
 130
 131 static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
 132                                          unsigned int count)
 133 {
 134         struct lpc32xx_hsuart_port *up = &lpc32xx_hs_ports[co->index];
 135         unsigned long flags;
 136         int locked = 1;
 137
 138         touch_nmi_watchdog();
 139         local_irq_save(flags);
 140         if (up->port.sysrq)
 141                 locked = 0;
 142         else if (oops_in_progress)
 143                 locked = spin_trylock(&up->port.lock);
 144         else
 145                 spin_lock(&up->port.lock);
 146
 147         uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
 148         wait_for_xmit_empty(&up->port);
 149
 150         if (locked)
 151                 spin_unlock(&up->port.lock);
 152         local_irq_restore(flags);
 153 }
 154
 155 static int __init lpc32xx_hsuart_console_setup(struct console *co,
 156                                                char *options)
 157 {
 158         struct uart_port *port;
 159         int baud = 115200;
 160         int bits = 8;
 161         int parity = 'n';
 162         int flow = 'n';
 163
 164         if (co->index >= MAX_PORTS)
 165                 co->index = 0;
 166
 167         port = &lpc32xx_hs_ports[co->index].port;
 168         if (!port->membase)
 169                 return -ENODEV;
 170
 171         if (options)
 172                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 173
 174         lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
 175
 176         return uart_set_options(port, co, baud, parity, bits, flow);
 177 }
 178
 179 static struct uart_driver lpc32xx_hsuart_reg;
 180 static struct console lpc32xx_hsuart_console = {
 181         .name           = LPC32XX_TTY_NAME,
 182         .write          = lpc32xx_hsuart_console_write,
 183         .device         = uart_console_device,
 184         .setup          = lpc32xx_hsuart_console_setup,
 185         .flags          = CON_PRINTBUFFER,
 186         .index          = -1,
 187         .data           = &lpc32xx_hsuart_reg,
 188 };
 189
 190 static int __init lpc32xx_hsuart_console_init(void)
 191 {
 192         register_console(&lpc32xx_hsuart_console);
 193         return 0;
 194 }
 195 console_initcall(lpc32xx_hsuart_console_init);
 196
 197 #define LPC32XX_HSUART_CONSOLE (&lpc32xx_hsuart_console)
 198 #else
 199 #define LPC32XX_HSUART_CONSOLE NULL
 200 #endif
 201
 202 static struct uart_driver lpc32xx_hs_reg = {
 203         .owner          = THIS_MODULE,
 204         .driver_name    = MODNAME,
 205         .dev_name       = LPC32XX_TTY_NAME,
 206         .nr             = MAX_PORTS,
 207         .cons           = LPC32XX_HSUART_CONSOLE,
 208 };
 209 static int uarts_registered;
 210
 211 static unsigned int __serial_get_clock_div(unsigned long uartclk,
 212                                            unsigned long rate)
 213 {
 214         u32 div, goodrate, hsu_rate, l_hsu_rate, comprate;
 215         u32 rate_diff;
 216
 217         /* Find the closest divider to get the desired clock rate */
 218         div = uartclk / rate;
 219         goodrate = hsu_rate = (div / 14) - 1;
 220         if (hsu_rate != 0)
 221                 hsu_rate--;
 222
 223         /* Tweak divider */
 224         l_hsu_rate = hsu_rate + 3;
 225         rate_diff = 0xFFFFFFFF;
 226
 227         while (hsu_rate < l_hsu_rate) {
 228                 comprate = uartclk / ((hsu_rate + 1) * 14);
 229                 if (abs(comprate - rate) < rate_diff) {
 230                         goodrate = hsu_rate;
 231                         rate_diff = abs(comprate - rate);
 232                 }
 233
 234                 hsu_rate++;
 235         }
 236         if (hsu_rate > 0xFF)
 237                 hsu_rate = 0xFF;
 238
 239         return goodrate;
 240 }
 241
 242 static void __serial_uart_flush(struct uart_port *port)
 243 {
 244         int cnt = 0;
 245
 246         while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
 247                (cnt++ < FIFO_READ_LIMIT))
 248                 readl(LPC32XX_HSUART_FIFO(port->membase));
 249 }
 250
 251 static void __serial_lpc32xx_rx(struct uart_port *port)
 252 {
 253         struct tty_port *tport = &port->state->port;
 254         unsigned int tmp, flag;
 255
 256         /* Read data from FIFO and push into terminal */
 257         tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 258         while (!(tmp & LPC32XX_HSU_RX_EMPTY)) {
 259                 flag = TTY_NORMAL;
 260                 port->icount.rx++;
 261
 262                 if (tmp & LPC32XX_HSU_ERROR_DATA) {
 263                         /* Framing error */
 264                         writel(LPC32XX_HSU_FE_INT,
 265                                LPC32XX_HSUART_IIR(port->membase));
 266                         port->icount.frame++;
 267                         flag = TTY_FRAME;
 268                         tty_insert_flip_char(tport, 0, TTY_FRAME);
 269                 }
 270
 271                 tty_insert_flip_char(tport, (tmp & 0xFF), flag);
 272
 273                 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 274         }
 275
 276         spin_unlock(&port->lock);
 277         tty_flip_buffer_push(tport);
 278         spin_lock(&port->lock);
 279 }
 280
 281 static void __serial_lpc32xx_tx(struct uart_port *port)
 282 {
 283         struct circ_buf *xmit = &port->state->xmit;
 284         unsigned int tmp;
 285
 286         if (port->x_char) {
 287                 writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
 288                 port->icount.tx++;
 289                 port->x_char = 0;
 290                 return;
 291         }
 292
 293         if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 294                 goto exit_tx;
 295
 296         /* Transfer data */
 297         while (LPC32XX_HSU_TX_LEV(readl(
 298                 LPC32XX_HSUART_LEVEL(port->membase))) < 64) {
 299                 writel((u32) xmit->buf[xmit->tail],
 300                        LPC32XX_HSUART_FIFO(port->membase));
 301                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 302                 port->icount.tx++;
 303                 if (uart_circ_empty(xmit))
 304                         break;
 305         }
 306
 307         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 308                 uart_write_wakeup(port);
 309
 310 exit_tx:
 311         if (uart_circ_empty(xmit)) {
 312                 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 313                 tmp &= ~LPC32XX_HSU_TX_INT_EN;
 314                 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 315         }
 316 }
 317
 318 static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 319 {
 320         struct uart_port *port = dev_id;
 321         struct tty_port *tport = &port->state->port;
 322         u32 status;
 323
 324         spin_lock(&port->lock);
 325
 326         /* Read UART status and clear latched interrupts */
 327         status = readl(LPC32XX_HSUART_IIR(port->membase));
 328
 329         if (status & LPC32XX_HSU_BRK_INT) {
 330                 /* Break received */
 331                 writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
 332                 port->icount.brk++;
 333                 uart_handle_break(port);
 334         }
 335
 336         /* Framing error */
 337         if (status & LPC32XX_HSU_FE_INT)
 338                 writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
 339
 340         if (status & LPC32XX_HSU_RX_OE_INT) {
 341                 /* Receive FIFO overrun */
 342                 writel(LPC32XX_HSU_RX_OE_INT,
 343                        LPC32XX_HSUART_IIR(port->membase));
 344                 port->icount.overrun++;
 345                 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 346                 tty_schedule_flip(tport);
 347         }
 348
 349         /* Data received? */
 350         if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
 351                 __serial_lpc32xx_rx(port);
 352
 353         /* Transmit data request? */
 354         if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
 355                 writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
 356                 __serial_lpc32xx_tx(port);
 357         }
 358
 359         spin_unlock(&port->lock);
 360
 361         return IRQ_HANDLED;
 362 }
 363
 364 /* port->lock is not held.  */
 365 static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
 366 {
 367         unsigned int ret = 0;
 368
 369         if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
 370                 ret = TIOCSER_TEMT;
 371
 372         return ret;
 373 }
 374
 375 /* port->lock held by caller.  */
 376 static void serial_lpc32xx_set_mctrl(struct uart_port *port,
 377                                      unsigned int mctrl)
 378 {
 379         /* No signals are supported on HS UARTs */
 380 }
 381
 382 /* port->lock is held by caller and interrupts are disabled.  */
 383 static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
 384 {
 385         /* No signals are supported on HS UARTs */
 386         return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 387 }
 388
 389 /* port->lock held by caller.  */
 390 static void serial_lpc32xx_stop_tx(struct uart_port *port)
 391 {
 392         u32 tmp;
 393
 394         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 395         tmp &= ~LPC32XX_HSU_TX_INT_EN;
 396         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 397 }
 398
 399 /* port->lock held by caller.  */
 400 static void serial_lpc32xx_start_tx(struct uart_port *port)
 401 {
 402         u32 tmp;
 403
 404         __serial_lpc32xx_tx(port);
 405         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 406         tmp |= LPC32XX_HSU_TX_INT_EN;
 407         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 408 }
 409
 410 /* port->lock held by caller.  */
 411 static void serial_lpc32xx_stop_rx(struct uart_port *port)
 412 {
 413         u32 tmp;
 414
 415         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 416         tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 417         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 418
 419         writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
 420                 LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
 421 }
 422
 423 /* port->lock is not held.  */
 424 static void serial_lpc32xx_break_ctl(struct uart_port *port,
 425                                      int break_state)
 426 {
 427         unsigned long flags;
 428         u32 tmp;
 429
 430         spin_lock_irqsave(&port->lock, flags);
 431         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 432         if (break_state != 0)
 433                 tmp |= LPC32XX_HSU_BREAK;
 434         else
 435                 tmp &= ~LPC32XX_HSU_BREAK;
 436         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 437         spin_unlock_irqrestore(&port->lock, flags);
 438 }
 439
 440 /* port->lock is not held.  */
 441 static int serial_lpc32xx_startup(struct uart_port *port)
 442 {
 443         int retval;
 444         unsigned long flags;
 445         u32 tmp;
 446
 447         spin_lock_irqsave(&port->lock, flags);
 448
 449         __serial_uart_flush(port);
 450
 451         writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 452                 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 453                LPC32XX_HSUART_IIR(port->membase));
 454
 455         writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 456
 457         /*
 458          * Set receiver timeout, HSU offset of 20, no break, no interrupts,
 459          * and default FIFO trigger levels
 460          */
 461         tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 462                 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 463         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 464
 465         lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
 466
 467         spin_unlock_irqrestore(&port->lock, flags);
 468
 469         retval = request_irq(port->irq, serial_lpc32xx_interrupt,
 470                              0, MODNAME, port);
 471         if (!retval)
 472                 writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
 473                        LPC32XX_HSUART_CTRL(port->membase));
 474
 475         return retval;
 476 }
 477
 478 /* port->lock is not held.  */
 479 static void serial_lpc32xx_shutdown(struct uart_port *port)
 480 {
 481         u32 tmp;
 482         unsigned long flags;
 483
 484         spin_lock_irqsave(&port->lock, flags);
 485
 486         tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 487                 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 488         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 489
 490         lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
 491
 492         spin_unlock_irqrestore(&port->lock, flags);
 493
 494         free_irq(port->irq, port);
 495 }
 496
 497 /* port->lock is not held.  */
 498 static void serial_lpc32xx_set_termios(struct uart_port *port,
 499                                        struct ktermios *termios,
 500                                        struct ktermios *old)
 501 {
 502         unsigned long flags;
 503         unsigned int baud, quot;
 504         u32 tmp;
 505
 506         /* Always 8-bit, no parity, 1 stop bit */
 507         termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
 508         termios->c_cflag |= CS8;
 509
 510         termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
 511
 512         baud = uart_get_baud_rate(port, termios, old, 0,
 513                                   port->uartclk / 14);
 514
 515         quot = __serial_get_clock_div(port->uartclk, baud);
 516
 517         spin_lock_irqsave(&port->lock, flags);
 518
 519         /* Ignore characters? */
 520         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 521         if ((termios->c_cflag & CREAD) == 0)
 522                 tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 523         else
 524                 tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
 525         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 526
 527         writel(quot, LPC32XX_HSUART_RATE(port->membase));
 528
 529         uart_update_timeout(port, termios->c_cflag, baud);
 530
 531         spin_unlock_irqrestore(&port->lock, flags);
 532
 533         /* Don't rewrite B0 */
 534         if (tty_termios_baud_rate(termios))
 535                 tty_termios_encode_baud_rate(termios, baud, baud);
 536 }
 537
 538 static const char *serial_lpc32xx_type(struct uart_port *port)
 539 {
 540         return MODNAME;
 541 }
 542
 543 static void serial_lpc32xx_release_port(struct uart_port *port)
 544 {
 545         if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 546                 if (port->flags & UPF_IOREMAP) {
 547                         iounmap(port->membase);
 548                         port->membase = NULL;
 549                 }
 550
 551                 release_mem_region(port->mapbase, SZ_4K);
 552         }
 553 }
 554
 555 static int serial_lpc32xx_request_port(struct uart_port *port)
 556 {
 557         int ret = -ENODEV;
 558
 559         if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 560                 ret = 0;
 561
 562                 if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
 563                         ret = -EBUSY;
 564                 else if (port->flags & UPF_IOREMAP) {
 565                         port->membase = ioremap(port->mapbase, SZ_4K);
 566                         if (!port->membase) {
 567                                 release_mem_region(port->mapbase, SZ_4K);
 568                                 ret = -ENOMEM;
 569                         }
 570                 }
 571         }
 572
 573         return ret;
 574 }
 575
 576 static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
 577 {
 578         int ret;
 579
 580         ret = serial_lpc32xx_request_port(port);
 581         if (ret < 0)
 582                 return;
 583         port->type = PORT_UART00;
 584         port->fifosize = 64;
 585
 586         __serial_uart_flush(port);
 587
 588         writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 589                 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 590                LPC32XX_HSUART_IIR(port->membase));
 591
 592         writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 593
 594         /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
 595            and default FIFO trigger levels */
 596         writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 597                LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
 598                LPC32XX_HSUART_CTRL(port->membase));
 599 }
 600
 601 static int serial_lpc32xx_verify_port(struct uart_port *port,
 602                                       struct serial_struct *ser)
 603 {
 604         int ret = 0;
 605
 606         if (ser->type != PORT_UART00)
 607                 ret = -EINVAL;
 608
 609         return ret;
 610 }
 611
 612 static const struct uart_ops serial_lpc32xx_pops = {
 613         .tx_empty       = serial_lpc32xx_tx_empty,
 614         .set_mctrl      = serial_lpc32xx_set_mctrl,
 615         .get_mctrl      = serial_lpc32xx_get_mctrl,
 616         .stop_tx        = serial_lpc32xx_stop_tx,
 617         .start_tx       = serial_lpc32xx_start_tx,
 618         .stop_rx        = serial_lpc32xx_stop_rx,
 619         .break_ctl      = serial_lpc32xx_break_ctl,
 620         .startup        = serial_lpc32xx_startup,
 621         .shutdown       = serial_lpc32xx_shutdown,
 622         .set_termios    = serial_lpc32xx_set_termios,
 623         .type           = serial_lpc32xx_type,
 624         .release_port   = serial_lpc32xx_release_port,
 625         .request_port   = serial_lpc32xx_request_port,
 626         .config_port    = serial_lpc32xx_config_port,
 627         .verify_port    = serial_lpc32xx_verify_port,
 628 };
 629
 630 /*
 631  * Register a set of serial devices attached to a platform device
 632  */
 633 static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
 634 {
 635         struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
 636         int ret = 0;
 637         struct resource *res;
 638
 639         if (uarts_registered >= MAX_PORTS) {
 640                 dev_err(&pdev->dev,
 641                         "Error: Number of possible ports exceeded (%d)!\n",
 642                         uarts_registered + 1);
 643                 return -ENXIO;
 644         }
 645
 646         memset(p, 0, sizeof(*p));
 647
 648         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 649         if (!res) {
 650                 dev_err(&pdev->dev,
 651                         "Error getting mem resource for HS UART port %d\n",
 652                         uarts_registered);
 653                 return -ENXIO;
 654         }
 655         p->port.mapbase = res->start;
 656         p->port.membase = NULL;
 657
 658         ret = platform_get_irq(pdev, 0);
 659         if (ret < 0)
 660                 return ret;
 661         p->port.irq = ret;
 662
 663         p->port.iotype = UPIO_MEM32;
 664         p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
 665         p->port.regshift = 2;
 666         p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
 667         p->port.dev = &pdev->dev;
 668         p->port.ops = &serial_lpc32xx_pops;
 669         p->port.line = uarts_registered++;
 670         spin_lock_init(&p->port.lock);
 671
 672         /* send port to loopback mode by default */
 673         lpc32xx_loopback_set(p->port.mapbase, 1);
 674
 675         ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
 676
 677         platform_set_drvdata(pdev, p);
 678
 679         return ret;
 680 }
 681
 682 /*
 683  * Remove serial ports registered against a platform device.
 684  */
 685 static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
 686 {
 687         struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 688
 689         uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
 690
 691         return 0;
 692 }
 693
 694
 695 #ifdef CONFIG_PM
 696 static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
 697                                      pm_message_t state)
 698 {
 699         struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 700
 701         uart_suspend_port(&lpc32xx_hs_reg, &p->port);
 702
 703         return 0;
 704 }
 705
 706 static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
 707 {
 708         struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 709
 710         uart_resume_port(&lpc32xx_hs_reg, &p->port);
 711
 712         return 0;
 713 }
 714 #else
 715 #define serial_hs_lpc32xx_suspend       NULL
 716 #define serial_hs_lpc32xx_resume        NULL
 717 #endif
 718
 719 static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
 720         { .compatible = "nxp,lpc3220-hsuart" },
 721         { /* sentinel */ }
 722 };
 723
 724 MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
 725
 726 static struct platform_driver serial_hs_lpc32xx_driver = {
 727         .probe          = serial_hs_lpc32xx_probe,
 728         .remove         = serial_hs_lpc32xx_remove,
 729         .suspend        = serial_hs_lpc32xx_suspend,
 730         .resume         = serial_hs_lpc32xx_resume,
 731         .driver         = {
 732                 .name   = MODNAME,
 733                 .of_match_table = serial_hs_lpc32xx_dt_ids,
 734         },
 735 };
 736
 737 static int __init lpc32xx_hsuart_init(void)
 738 {
 739         int ret;
 740
 741         ret = uart_register_driver(&lpc32xx_hs_reg);
 742         if (ret)
 743                 return ret;
 744
 745         ret = platform_driver_register(&serial_hs_lpc32xx_driver);
 746         if (ret)
 747                 uart_unregister_driver(&lpc32xx_hs_reg);
 748
 749         return ret;
 750 }
 751
 752 static void __exit lpc32xx_hsuart_exit(void)
 753 {
 754         platform_driver_unregister(&serial_hs_lpc32xx_driver);
 755         uart_unregister_driver(&lpc32xx_hs_reg);
 756 }
 757
 758 module_init(lpc32xx_hsuart_init);
 759 module_exit(lpc32xx_hsuart_exit);
 760
 761 MODULE_AUTHOR("Kevin Wells <[email protected]>");
 762 MODULE_AUTHOR("Roland Stigge <[email protected]>");
 763 MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
 764 MODULE_LICENSE("GPL");