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 <kevin.wells@nxp.com>
   6  *          Roland Stigge <stigge@antcom.de>
   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, unsigned char 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         tty_flip_buffer_push(tport);
 277 }
 278
 279 static void serial_lpc32xx_stop_tx(struct uart_port *port);
 280
 281 static bool serial_lpc32xx_tx_ready(struct uart_port *port)
 282 {
 283         u32 level = readl(LPC32XX_HSUART_LEVEL(port->membase));
 284
 285         return LPC32XX_HSU_TX_LEV(level) < 64;
 286 }
 287
 288 static void __serial_lpc32xx_tx(struct uart_port *port)
 289 {
 290         struct circ_buf *xmit = &port->state->xmit;
 291
 292         if (port->x_char) {
 293                 writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
 294                 port->icount.tx++;
 295                 port->x_char = 0;
 296                 return;
 297         }
 298
 299         if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 300                 goto exit_tx;
 301
 302         /* Transfer data */
 303         while (serial_lpc32xx_tx_ready(port)) {
 304                 writel((u32) xmit->buf[xmit->tail],
 305                        LPC32XX_HSUART_FIFO(port->membase));
 306                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 307                 port->icount.tx++;
 308                 if (uart_circ_empty(xmit))
 309                         break;
 310         }
 311
 312         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 313                 uart_write_wakeup(port);
 314
 315 exit_tx:
 316         if (uart_circ_empty(xmit))
 317                 serial_lpc32xx_stop_tx(port);
 318 }
 319
 320 static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 321 {
 322         struct uart_port *port = dev_id;
 323         struct tty_port *tport = &port->state->port;
 324         u32 status;
 325
 326         spin_lock(&port->lock);
 327
 328         /* Read UART status and clear latched interrupts */
 329         status = readl(LPC32XX_HSUART_IIR(port->membase));
 330
 331         if (status & LPC32XX_HSU_BRK_INT) {
 332                 /* Break received */
 333                 writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
 334                 port->icount.brk++;
 335                 uart_handle_break(port);
 336         }
 337
 338         /* Framing error */
 339         if (status & LPC32XX_HSU_FE_INT)
 340                 writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
 341
 342         if (status & LPC32XX_HSU_RX_OE_INT) {
 343                 /* Receive FIFO overrun */
 344                 writel(LPC32XX_HSU_RX_OE_INT,
 345                        LPC32XX_HSUART_IIR(port->membase));
 346                 port->icount.overrun++;
 347                 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 348                 tty_flip_buffer_push(tport);
 349         }
 350
 351         /* Data received? */
 352         if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
 353                 __serial_lpc32xx_rx(port);
 354
 355         /* Transmit data request? */
 356         if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
 357                 writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
 358                 __serial_lpc32xx_tx(port);
 359         }
 360
 361         spin_unlock(&port->lock);
 362
 363         return IRQ_HANDLED;
 364 }
 365
 366 /* port->lock is not held.  */
 367 static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
 368 {
 369         unsigned int ret = 0;
 370
 371         if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
 372                 ret = TIOCSER_TEMT;
 373
 374         return ret;
 375 }
 376
 377 /* port->lock held by caller.  */
 378 static void serial_lpc32xx_set_mctrl(struct uart_port *port,
 379                                      unsigned int mctrl)
 380 {
 381         /* No signals are supported on HS UARTs */
 382 }
 383
 384 /* port->lock is held by caller and interrupts are disabled.  */
 385 static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
 386 {
 387         /* No signals are supported on HS UARTs */
 388         return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 389 }
 390
 391 /* port->lock held by caller.  */
 392 static void serial_lpc32xx_stop_tx(struct uart_port *port)
 393 {
 394         u32 tmp;
 395
 396         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 397         tmp &= ~LPC32XX_HSU_TX_INT_EN;
 398         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 399 }
 400
 401 /* port->lock held by caller.  */
 402 static void serial_lpc32xx_start_tx(struct uart_port *port)
 403 {
 404         u32 tmp;
 405
 406         __serial_lpc32xx_tx(port);
 407         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 408         tmp |= LPC32XX_HSU_TX_INT_EN;
 409         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 410 }
 411
 412 /* port->lock held by caller.  */
 413 static void serial_lpc32xx_stop_rx(struct uart_port *port)
 414 {
 415         u32 tmp;
 416
 417         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 418         tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 419         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 420
 421         writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
 422                 LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
 423 }
 424
 425 /* port->lock is not held.  */
 426 static void serial_lpc32xx_break_ctl(struct uart_port *port,
 427                                      int break_state)
 428 {
 429         unsigned long flags;
 430         u32 tmp;
 431
 432         spin_lock_irqsave(&port->lock, flags);
 433         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 434         if (break_state != 0)
 435                 tmp |= LPC32XX_HSU_BREAK;
 436         else
 437                 tmp &= ~LPC32XX_HSU_BREAK;
 438         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 439         spin_unlock_irqrestore(&port->lock, flags);
 440 }
 441
 442 /* port->lock is not held.  */
 443 static int serial_lpc32xx_startup(struct uart_port *port)
 444 {
 445         int retval;
 446         unsigned long flags;
 447         u32 tmp;
 448
 449         spin_lock_irqsave(&port->lock, flags);
 450
 451         __serial_uart_flush(port);
 452
 453         writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 454                 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 455                LPC32XX_HSUART_IIR(port->membase));
 456
 457         writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 458
 459         /*
 460          * Set receiver timeout, HSU offset of 20, no break, no interrupts,
 461          * and default FIFO trigger levels
 462          */
 463         tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 464                 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 465         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 466
 467         lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
 468
 469         spin_unlock_irqrestore(&port->lock, flags);
 470
 471         retval = request_irq(port->irq, serial_lpc32xx_interrupt,
 472                              0, MODNAME, port);
 473         if (!retval)
 474                 writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
 475                        LPC32XX_HSUART_CTRL(port->membase));
 476
 477         return retval;
 478 }
 479
 480 /* port->lock is not held.  */
 481 static void serial_lpc32xx_shutdown(struct uart_port *port)
 482 {
 483         u32 tmp;
 484         unsigned long flags;
 485
 486         spin_lock_irqsave(&port->lock, flags);
 487
 488         tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 489                 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
 490         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 491
 492         lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
 493
 494         spin_unlock_irqrestore(&port->lock, flags);
 495
 496         free_irq(port->irq, port);
 497 }
 498
 499 /* port->lock is not held.  */
 500 static void serial_lpc32xx_set_termios(struct uart_port *port,
 501                                        struct ktermios *termios,
 502                                        const struct ktermios *old)
 503 {
 504         unsigned long flags;
 505         unsigned int baud, quot;
 506         u32 tmp;
 507
 508         /* Always 8-bit, no parity, 1 stop bit */
 509         termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
 510         termios->c_cflag |= CS8;
 511
 512         termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
 513
 514         baud = uart_get_baud_rate(port, termios, old, 0,
 515                                   port->uartclk / 14);
 516
 517         quot = __serial_get_clock_div(port->uartclk, baud);
 518
 519         spin_lock_irqsave(&port->lock, flags);
 520
 521         /* Ignore characters? */
 522         tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
 523         if ((termios->c_cflag & CREAD) == 0)
 524                 tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
 525         else
 526                 tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
 527         writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
 528
 529         writel(quot, LPC32XX_HSUART_RATE(port->membase));
 530
 531         uart_update_timeout(port, termios->c_cflag, baud);
 532
 533         spin_unlock_irqrestore(&port->lock, flags);
 534
 535         /* Don't rewrite B0 */
 536         if (tty_termios_baud_rate(termios))
 537                 tty_termios_encode_baud_rate(termios, baud, baud);
 538 }
 539
 540 static const char *serial_lpc32xx_type(struct uart_port *port)
 541 {
 542         return MODNAME;
 543 }
 544
 545 static void serial_lpc32xx_release_port(struct uart_port *port)
 546 {
 547         if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 548                 if (port->flags & UPF_IOREMAP) {
 549                         iounmap(port->membase);
 550                         port->membase = NULL;
 551                 }
 552
 553                 release_mem_region(port->mapbase, SZ_4K);
 554         }
 555 }
 556
 557 static int serial_lpc32xx_request_port(struct uart_port *port)
 558 {
 559         int ret = -ENODEV;
 560
 561         if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
 562                 ret = 0;
 563
 564                 if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
 565                         ret = -EBUSY;
 566                 else if (port->flags & UPF_IOREMAP) {
 567                         port->membase = ioremap(port->mapbase, SZ_4K);
 568                         if (!port->membase) {
 569                                 release_mem_region(port->mapbase, SZ_4K);
 570                                 ret = -ENOMEM;
 571                         }
 572                 }
 573         }
 574
 575         return ret;
 576 }
 577
 578 static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
 579 {
 580         int ret;
 581
 582         ret = serial_lpc32xx_request_port(port);
 583         if (ret < 0)
 584                 return;
 585         port->type = PORT_UART00;
 586         port->fifosize = 64;
 587
 588         __serial_uart_flush(port);
 589
 590         writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
 591                 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
 592                LPC32XX_HSUART_IIR(port->membase));
 593
 594         writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
 595
 596         /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
 597            and default FIFO trigger levels */
 598         writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
 599                LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
 600                LPC32XX_HSUART_CTRL(port->membase));
 601 }
 602
 603 static int serial_lpc32xx_verify_port(struct uart_port *port,
 604                                       struct serial_struct *ser)
 605 {
 606         int ret = 0;
 607
 608         if (ser->type != PORT_UART00)
 609                 ret = -EINVAL;
 610
 611         return ret;
 612 }
 613
 614 static const struct uart_ops serial_lpc32xx_pops = {
 615         .tx_empty       = serial_lpc32xx_tx_empty,
 616         .set_mctrl      = serial_lpc32xx_set_mctrl,
 617         .get_mctrl      = serial_lpc32xx_get_mctrl,
 618         .stop_tx        = serial_lpc32xx_stop_tx,
 619         .start_tx       = serial_lpc32xx_start_tx,
 620         .stop_rx        = serial_lpc32xx_stop_rx,
 621         .break_ctl      = serial_lpc32xx_break_ctl,
 622         .startup        = serial_lpc32xx_startup,
 623         .shutdown       = serial_lpc32xx_shutdown,
 624         .set_termios    = serial_lpc32xx_set_termios,
 625         .type           = serial_lpc32xx_type,
 626         .release_port   = serial_lpc32xx_release_port,
 627         .request_port   = serial_lpc32xx_request_port,
 628         .config_port    = serial_lpc32xx_config_port,
 629         .verify_port    = serial_lpc32xx_verify_port,
 630 };
 631
 632 /*
 633  * Register a set of serial devices attached to a platform device
 634  */
 635 static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
 636 {
 637         struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
 638         int ret = 0;
 639         struct resource *res;
 640
 641         if (uarts_registered >= MAX_PORTS) {
 642                 dev_err(&pdev->dev,
 643                         "Error: Number of possible ports exceeded (%d)!\n",
 644                         uarts_registered + 1);
 645                 return -ENXIO;
 646         }
 647
 648         memset(p, 0, sizeof(*p));
 649
 650         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 651         if (!res) {
 652                 dev_err(&pdev->dev,
 653                         "Error getting mem resource for HS UART port %d\n",
 654                         uarts_registered);
 655                 return -ENXIO;
 656         }
 657         p->port.mapbase = res->start;
 658         p->port.membase = NULL;
 659
 660         ret = platform_get_irq(pdev, 0);
 661         if (ret < 0)
 662                 return ret;
 663         p->port.irq = ret;
 664
 665         p->port.iotype = UPIO_MEM32;
 666         p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
 667         p->port.regshift = 2;
 668         p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
 669         p->port.dev = &pdev->dev;
 670         p->port.ops = &serial_lpc32xx_pops;
 671         p->port.line = uarts_registered++;
 672         spin_lock_init(&p->port.lock);
 673
 674         /* send port to loopback mode by default */
 675         lpc32xx_loopback_set(p->port.mapbase, 1);
 676
 677         ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
 678
 679         platform_set_drvdata(pdev, p);
 680
 681         return ret;
 682 }
 683
 684 /*
 685  * Remove serial ports registered against a platform device.
 686  */
 687 static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
 688 {
 689         struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 690
 691         uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
 692
 693         return 0;
 694 }
 695
 696
 697 #ifdef CONFIG_PM
 698 static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
 699                                      pm_message_t state)
 700 {
 701         struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 702
 703         uart_suspend_port(&lpc32xx_hs_reg, &p->port);
 704
 705         return 0;
 706 }
 707
 708 static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
 709 {
 710         struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
 711
 712         uart_resume_port(&lpc32xx_hs_reg, &p->port);
 713
 714         return 0;
 715 }
 716 #else
 717 #define serial_hs_lpc32xx_suspend       NULL
 718 #define serial_hs_lpc32xx_resume        NULL
 719 #endif
 720
 721 static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
 722         { .compatible = "nxp,lpc3220-hsuart" },
 723         { /* sentinel */ }
 724 };
 725
 726 MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
 727
 728 static struct platform_driver serial_hs_lpc32xx_driver = {
 729         .probe          = serial_hs_lpc32xx_probe,
 730         .remove         = serial_hs_lpc32xx_remove,
 731         .suspend        = serial_hs_lpc32xx_suspend,
 732         .resume         = serial_hs_lpc32xx_resume,
 733         .driver         = {
 734                 .name   = MODNAME,
 735                 .of_match_table = serial_hs_lpc32xx_dt_ids,
 736         },
 737 };
 738
 739 static int __init lpc32xx_hsuart_init(void)
 740 {
 741         int ret;
 742
 743         ret = uart_register_driver(&lpc32xx_hs_reg);
 744         if (ret)
 745                 return ret;
 746
 747         ret = platform_driver_register(&serial_hs_lpc32xx_driver);
 748         if (ret)
 749                 uart_unregister_driver(&lpc32xx_hs_reg);
 750
 751         return ret;
 752 }
 753
 754 static void __exit lpc32xx_hsuart_exit(void)
 755 {
 756         platform_driver_unregister(&serial_hs_lpc32xx_driver);
 757         uart_unregister_driver(&lpc32xx_hs_reg);
 758 }
 759
 760 module_init(lpc32xx_hsuart_init);
 761 module_exit(lpc32xx_hsuart_exit);
 762
 763 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
 764 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
 765 MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
 766 MODULE_LICENSE("GPL");