drivers/tty/serial/omap-serial.c

   1 /*
   2  * Driver for OMAP-UART controller.
   3  * Based on drivers/serial/8250.c
   4  *
   5  * Copyright (C) 2010 Texas Instruments.
   6  *
   7  * Authors:
   8  *      Govindraj R     <govindraj.raja@ti.com>
   9  *      Thara Gopinath  <thara@ti.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * Note: This driver is made separate from 8250 driver as we cannot
  17  * over load 8250 driver with omap platform specific configuration for
  18  * features like DMA, it makes easier to implement features like DMA and
  19  * hardware flow control and software flow control configuration with
  20  * this driver as required for the omap-platform.
  21  */
  22
  23 #if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  24 #define SUPPORT_SYSRQ
  25 #endif
  26
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/console.h>
  30 #include <linux/serial_reg.h>
  31 #include <linux/delay.h>
  32 #include <linux/slab.h>
  33 #include <linux/tty.h>
  34 #include <linux/tty_flip.h>
  35 #include <linux/io.h>
  36 #include <linux/dma-mapping.h>
  37 #include <linux/clk.h>
  38 #include <linux/serial_core.h>
  39 #include <linux/irq.h>
  40 #include <linux/pm_runtime.h>
  41
  42 #include <plat/dma.h>
  43 #include <plat/dmtimer.h>
  44 #include <plat/omap-serial.h>
  45
  46 #define OMAP_UART_AUTOSUSPEND_DELAY -1
  47
  48 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
  49
  50 /* Forward declaration of functions */
  51 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
  52 static void serial_omap_rx_timeout(unsigned long uart_no);
  53 static int serial_omap_start_rxdma(struct uart_omap_port *up);
  54
  55 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
  56 {
  57         offset <<= up->port.regshift;
  58         return readw(up->port.membase + offset);
  59 }
  60
  61 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
  62 {
  63         offset <<= up->port.regshift;
  64         writew(value, up->port.membase + offset);
  65 }
  66
  67 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
  68 {
  69         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
  70         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
  71                        UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
  72         serial_out(up, UART_FCR, 0);
  73 }
  74
  75 /*
  76  * serial_omap_get_divisor - calculate divisor value
  77  * @port: uart port info
  78  * @baud: baudrate for which divisor needs to be calculated.
  79  *
  80  * We have written our own function to get the divisor so as to support
  81  * 13x mode. 3Mbps Baudrate as an different divisor.
  82  * Reference OMAP TRM Chapter 17:
  83  * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
  84  * referring to oversampling - divisor value
  85  * baudrate 460,800 to 3,686,400 all have divisor 13
  86  * except 3,000,000 which has divisor value 16
  87  */
  88 static unsigned int
  89 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
  90 {
  91         unsigned int divisor;
  92
  93         if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
  94                 divisor = 13;
  95         else
  96                 divisor = 16;
  97         return port->uartclk/(baud * divisor);
  98 }
  99
 100 static void serial_omap_stop_rxdma(struct uart_omap_port *up)
 101 {
 102         if (up->uart_dma.rx_dma_used) {
 103                 del_timer(&up->uart_dma.rx_timer);
 104                 omap_stop_dma(up->uart_dma.rx_dma_channel);
 105                 omap_free_dma(up->uart_dma.rx_dma_channel);
 106                 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
 107                 up->uart_dma.rx_dma_used = false;
 108                 pm_runtime_mark_last_busy(&up->pdev->dev);
 109                 pm_runtime_put_autosuspend(&up->pdev->dev);
 110         }
 111 }
 112
 113 static void serial_omap_enable_ms(struct uart_port *port)
 114 {
 115         struct uart_omap_port *up = (struct uart_omap_port *)port;
 116
 117         dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->pdev->id);
 118
 119         pm_runtime_get_sync(&up->pdev->dev);
 120         up->ier |= UART_IER_MSI;
 121         serial_out(up, UART_IER, up->ier);
 122         pm_runtime_put(&up->pdev->dev);
 123 }
 124
 125 static void serial_omap_stop_tx(struct uart_port *port)
 126 {
 127         struct uart_omap_port *up = (struct uart_omap_port *)port;
 128
 129         if (up->use_dma &&
 130                 up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
 131                 /*
 132                  * Check if dma is still active. If yes do nothing,
 133                  * return. Else stop dma
 134                  */
 135                 if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
 136                         return;
 137                 omap_stop_dma(up->uart_dma.tx_dma_channel);
 138                 omap_free_dma(up->uart_dma.tx_dma_channel);
 139                 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
 140                 pm_runtime_mark_last_busy(&up->pdev->dev);
 141                 pm_runtime_put_autosuspend(&up->pdev->dev);
 142         }
 143
 144         pm_runtime_get_sync(&up->pdev->dev);
 145         if (up->ier & UART_IER_THRI) {
 146                 up->ier &= ~UART_IER_THRI;
 147                 serial_out(up, UART_IER, up->ier);
 148         }
 149
 150         pm_runtime_mark_last_busy(&up->pdev->dev);
 151         pm_runtime_put_autosuspend(&up->pdev->dev);
 152 }
 153
 154 static void serial_omap_stop_rx(struct uart_port *port)
 155 {
 156         struct uart_omap_port *up = (struct uart_omap_port *)port;
 157
 158         pm_runtime_get_sync(&up->pdev->dev);
 159         if (up->use_dma)
 160                 serial_omap_stop_rxdma(up);
 161         up->ier &= ~UART_IER_RLSI;
 162         up->port.read_status_mask &= ~UART_LSR_DR;
 163         serial_out(up, UART_IER, up->ier);
 164         pm_runtime_mark_last_busy(&up->pdev->dev);
 165         pm_runtime_put_autosuspend(&up->pdev->dev);
 166 }
 167
 168 static inline void receive_chars(struct uart_omap_port *up, int *status)
 169 {
 170         struct tty_struct *tty = up->port.state->port.tty;
 171         unsigned int flag;
 172         unsigned char ch, lsr = *status;
 173         int max_count = 256;
 174
 175         do {
 176                 if (likely(lsr & UART_LSR_DR))
 177                         ch = serial_in(up, UART_RX);
 178                 flag = TTY_NORMAL;
 179                 up->port.icount.rx++;
 180
 181                 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
 182                         /*
 183                          * For statistics only
 184                          */
 185                         if (lsr & UART_LSR_BI) {
 186                                 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
 187                                 up->port.icount.brk++;
 188                                 /*
 189                                  * We do the SysRQ and SAK checking
 190                                  * here because otherwise the break
 191                                  * may get masked by ignore_status_mask
 192                                  * or read_status_mask.
 193                                  */
 194                                 if (uart_handle_break(&up->port))
 195                                         goto ignore_char;
 196                         } else if (lsr & UART_LSR_PE) {
 197                                 up->port.icount.parity++;
 198                         } else if (lsr & UART_LSR_FE) {
 199                                 up->port.icount.frame++;
 200                         }
 201
 202                         if (lsr & UART_LSR_OE)
 203                                 up->port.icount.overrun++;
 204
 205                         /*
 206                          * Mask off conditions which should be ignored.
 207                          */
 208                         lsr &= up->port.read_status_mask;
 209
 210 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
 211                         if (up->port.line == up->port.cons->index) {
 212                                 /* Recover the break flag from console xmit */
 213                                 lsr |= up->lsr_break_flag;
 214                         }
 215 #endif
 216                         if (lsr & UART_LSR_BI)
 217                                 flag = TTY_BREAK;
 218                         else if (lsr & UART_LSR_PE)
 219                                 flag = TTY_PARITY;
 220                         else if (lsr & UART_LSR_FE)
 221                                 flag = TTY_FRAME;
 222                 }
 223
 224                 if (uart_handle_sysrq_char(&up->port, ch))
 225                         goto ignore_char;
 226                 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
 227 ignore_char:
 228                 lsr = serial_in(up, UART_LSR);
 229         } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
 230         spin_unlock(&up->port.lock);
 231         tty_flip_buffer_push(tty);
 232         spin_lock(&up->port.lock);
 233 }
 234
 235 static void transmit_chars(struct uart_omap_port *up)
 236 {
 237         struct circ_buf *xmit = &up->port.state->xmit;
 238         int count;
 239
 240         if (up->port.x_char) {
 241                 serial_out(up, UART_TX, up->port.x_char);
 242                 up->port.icount.tx++;
 243                 up->port.x_char = 0;
 244                 return;
 245         }
 246         if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 247                 serial_omap_stop_tx(&up->port);
 248                 return;
 249         }
 250         count = up->port.fifosize / 4;
 251         do {
 252                 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 253                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 254                 up->port.icount.tx++;
 255                 if (uart_circ_empty(xmit))
 256                         break;
 257         } while (--count > 0);
 258
 259         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 260                 uart_write_wakeup(&up->port);
 261
 262         if (uart_circ_empty(xmit))
 263                 serial_omap_stop_tx(&up->port);
 264 }
 265
 266 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
 267 {
 268         if (!(up->ier & UART_IER_THRI)) {
 269                 up->ier |= UART_IER_THRI;
 270                 serial_out(up, UART_IER, up->ier);
 271         }
 272 }
 273
 274 static void serial_omap_start_tx(struct uart_port *port)
 275 {
 276         struct uart_omap_port *up = (struct uart_omap_port *)port;
 277         struct circ_buf *xmit;
 278         unsigned int start;
 279         int ret = 0;
 280
 281         if (!up->use_dma) {
 282                 pm_runtime_get_sync(&up->pdev->dev);
 283                 serial_omap_enable_ier_thri(up);
 284                 pm_runtime_mark_last_busy(&up->pdev->dev);
 285                 pm_runtime_put_autosuspend(&up->pdev->dev);
 286                 return;
 287         }
 288
 289         if (up->uart_dma.tx_dma_used)
 290                 return;
 291
 292         xmit = &up->port.state->xmit;
 293
 294         if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
 295                 pm_runtime_get_sync(&up->pdev->dev);
 296                 ret = omap_request_dma(up->uart_dma.uart_dma_tx,
 297                                 "UART Tx DMA",
 298                                 (void *)uart_tx_dma_callback, up,
 299                                 &(up->uart_dma.tx_dma_channel));
 300
 301                 if (ret < 0) {
 302                         serial_omap_enable_ier_thri(up);
 303                         return;
 304                 }
 305         }
 306         spin_lock(&(up->uart_dma.tx_lock));
 307         up->uart_dma.tx_dma_used = true;
 308         spin_unlock(&(up->uart_dma.tx_lock));
 309
 310         start = up->uart_dma.tx_buf_dma_phys +
 311                                 (xmit->tail & (UART_XMIT_SIZE - 1));
 312
 313         up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
 314         /*
 315          * It is a circular buffer. See if the buffer has wounded back.
 316          * If yes it will have to be transferred in two separate dma
 317          * transfers
 318          */
 319         if (start + up->uart_dma.tx_buf_size >=
 320                         up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
 321                 up->uart_dma.tx_buf_size =
 322                         (up->uart_dma.tx_buf_dma_phys +
 323                         UART_XMIT_SIZE) - start;
 324
 325         omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
 326                                 OMAP_DMA_AMODE_CONSTANT,
 327                                 up->uart_dma.uart_base, 0, 0);
 328         omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
 329                                 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
 330         omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
 331                                 OMAP_DMA_DATA_TYPE_S8,
 332                                 up->uart_dma.tx_buf_size, 1,
 333                                 OMAP_DMA_SYNC_ELEMENT,
 334                                 up->uart_dma.uart_dma_tx, 0);
 335         /* FIXME: Cache maintenance needed here? */
 336         omap_start_dma(up->uart_dma.tx_dma_channel);
 337 }
 338
 339 static unsigned int check_modem_status(struct uart_omap_port *up)
 340 {
 341         unsigned int status;
 342
 343         status = serial_in(up, UART_MSR);
 344         status |= up->msr_saved_flags;
 345         up->msr_saved_flags = 0;
 346         if ((status & UART_MSR_ANY_DELTA) == 0)
 347                 return status;
 348
 349         if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
 350             up->port.state != NULL) {
 351                 if (status & UART_MSR_TERI)
 352                         up->port.icount.rng++;
 353                 if (status & UART_MSR_DDSR)
 354                         up->port.icount.dsr++;
 355                 if (status & UART_MSR_DDCD)
 356                         uart_handle_dcd_change
 357                                 (&up->port, status & UART_MSR_DCD);
 358                 if (status & UART_MSR_DCTS)
 359                         uart_handle_cts_change
 360                                 (&up->port, status & UART_MSR_CTS);
 361                 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 362         }
 363
 364         return status;
 365 }
 366
 367 /**
 368  * serial_omap_irq() - This handles the interrupt from one port
 369  * @irq: uart port irq number
 370  * @dev_id: uart port info
 371  */
 372 static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
 373 {
 374         struct uart_omap_port *up = dev_id;
 375         unsigned int iir, lsr;
 376         unsigned long flags;
 377
 378         pm_runtime_get_sync(&up->pdev->dev);
 379         iir = serial_in(up, UART_IIR);
 380         if (iir & UART_IIR_NO_INT) {
 381                 pm_runtime_mark_last_busy(&up->pdev->dev);
 382                 pm_runtime_put_autosuspend(&up->pdev->dev);
 383                 return IRQ_NONE;
 384         }
 385
 386         spin_lock_irqsave(&up->port.lock, flags);
 387         lsr = serial_in(up, UART_LSR);
 388         if (iir & UART_IIR_RLSI) {
 389                 if (!up->use_dma) {
 390                         if (lsr & UART_LSR_DR)
 391                                 receive_chars(up, &lsr);
 392                 } else {
 393                         up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
 394                         serial_out(up, UART_IER, up->ier);
 395                         if ((serial_omap_start_rxdma(up) != 0) &&
 396                                         (lsr & UART_LSR_DR))
 397                                 receive_chars(up, &lsr);
 398                 }
 399         }
 400
 401         check_modem_status(up);
 402         if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
 403                 transmit_chars(up);
 404
 405         spin_unlock_irqrestore(&up->port.lock, flags);
 406         pm_runtime_mark_last_busy(&up->pdev->dev);
 407         pm_runtime_put_autosuspend(&up->pdev->dev);
 408
 409         up->port_activity = jiffies;
 410         return IRQ_HANDLED;
 411 }
 412
 413 static unsigned int serial_omap_tx_empty(struct uart_port *port)
 414 {
 415         struct uart_omap_port *up = (struct uart_omap_port *)port;
 416         unsigned long flags = 0;
 417         unsigned int ret = 0;
 418
 419         pm_runtime_get_sync(&up->pdev->dev);
 420         dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->pdev->id);
 421         spin_lock_irqsave(&up->port.lock, flags);
 422         ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 423         spin_unlock_irqrestore(&up->port.lock, flags);
 424         pm_runtime_put(&up->pdev->dev);
 425         return ret;
 426 }
 427
 428 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
 429 {
 430         struct uart_omap_port *up = (struct uart_omap_port *)port;
 431         unsigned char status;
 432         unsigned int ret = 0;
 433
 434         pm_runtime_get_sync(&up->pdev->dev);
 435         status = check_modem_status(up);
 436         pm_runtime_put(&up->pdev->dev);
 437
 438         dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->pdev->id);
 439
 440         if (status & UART_MSR_DCD)
 441                 ret |= TIOCM_CAR;
 442         if (status & UART_MSR_RI)
 443                 ret |= TIOCM_RNG;
 444         if (status & UART_MSR_DSR)
 445                 ret |= TIOCM_DSR;
 446         if (status & UART_MSR_CTS)
 447                 ret |= TIOCM_CTS;
 448         return ret;
 449 }
 450
 451 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 452 {
 453         struct uart_omap_port *up = (struct uart_omap_port *)port;
 454         unsigned char mcr = 0;
 455
 456         dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->pdev->id);
 457         if (mctrl & TIOCM_RTS)
 458                 mcr |= UART_MCR_RTS;
 459         if (mctrl & TIOCM_DTR)
 460                 mcr |= UART_MCR_DTR;
 461         if (mctrl & TIOCM_OUT1)
 462                 mcr |= UART_MCR_OUT1;
 463         if (mctrl & TIOCM_OUT2)
 464                 mcr |= UART_MCR_OUT2;
 465         if (mctrl & TIOCM_LOOP)
 466                 mcr |= UART_MCR_LOOP;
 467
 468         pm_runtime_get_sync(&up->pdev->dev);
 469         up->mcr = serial_in(up, UART_MCR);
 470         up->mcr |= mcr;
 471         serial_out(up, UART_MCR, up->mcr);
 472         pm_runtime_put(&up->pdev->dev);
 473 }
 474
 475 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
 476 {
 477         struct uart_omap_port *up = (struct uart_omap_port *)port;
 478         unsigned long flags = 0;
 479
 480         dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->pdev->id);
 481         pm_runtime_get_sync(&up->pdev->dev);
 482         spin_lock_irqsave(&up->port.lock, flags);
 483         if (break_state == -1)
 484                 up->lcr |= UART_LCR_SBC;
 485         else
 486                 up->lcr &= ~UART_LCR_SBC;
 487         serial_out(up, UART_LCR, up->lcr);
 488         spin_unlock_irqrestore(&up->port.lock, flags);
 489         pm_runtime_put(&up->pdev->dev);
 490 }
 491
 492 static int serial_omap_startup(struct uart_port *port)
 493 {
 494         struct uart_omap_port *up = (struct uart_omap_port *)port;
 495         unsigned long flags = 0;
 496         int retval;
 497
 498         /*
 499          * Allocate the IRQ
 500          */
 501         retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
 502                                 up->name, up);
 503         if (retval)
 504                 return retval;
 505
 506         dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->pdev->id);
 507
 508         pm_runtime_get_sync(&up->pdev->dev);
 509         /*
 510          * Clear the FIFO buffers and disable them.
 511          * (they will be reenabled in set_termios())
 512          */
 513         serial_omap_clear_fifos(up);
 514         /* For Hardware flow control */
 515         serial_out(up, UART_MCR, UART_MCR_RTS);
 516
 517         /*
 518          * Clear the interrupt registers.
 519          */
 520         (void) serial_in(up, UART_LSR);
 521         if (serial_in(up, UART_LSR) & UART_LSR_DR)
 522                 (void) serial_in(up, UART_RX);
 523         (void) serial_in(up, UART_IIR);
 524         (void) serial_in(up, UART_MSR);
 525
 526         /*
 527          * Now, initialize the UART
 528          */
 529         serial_out(up, UART_LCR, UART_LCR_WLEN8);
 530         spin_lock_irqsave(&up->port.lock, flags);
 531         /*
 532          * Most PC uarts need OUT2 raised to enable interrupts.
 533          */
 534         up->port.mctrl |= TIOCM_OUT2;
 535         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 536         spin_unlock_irqrestore(&up->port.lock, flags);
 537
 538         up->msr_saved_flags = 0;
 539         if (up->use_dma) {
 540                 free_page((unsigned long)up->port.state->xmit.buf);
 541                 up->port.state->xmit.buf = dma_alloc_coherent(NULL,
 542                         UART_XMIT_SIZE,
 543                         (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
 544                         0);
 545                 init_timer(&(up->uart_dma.rx_timer));
 546                 up->uart_dma.rx_timer.function = serial_omap_rx_timeout;
 547                 up->uart_dma.rx_timer.data = up->pdev->id;
 548                 /* Currently the buffer size is 4KB. Can increase it */
 549                 up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
 550                         up->uart_dma.rx_buf_size,
 551                         (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0);
 552         }
 553         /*
 554          * Finally, enable interrupts. Note: Modem status interrupts
 555          * are set via set_termios(), which will be occurring imminently
 556          * anyway, so we don't enable them here.
 557          */
 558         up->ier = UART_IER_RLSI | UART_IER_RDI;
 559         serial_out(up, UART_IER, up->ier);
 560
 561         /* Enable module level wake up */
 562         serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
 563
 564         pm_runtime_mark_last_busy(&up->pdev->dev);
 565         pm_runtime_put_autosuspend(&up->pdev->dev);
 566         up->port_activity = jiffies;
 567         return 0;
 568 }
 569
 570 static void serial_omap_shutdown(struct uart_port *port)
 571 {
 572         struct uart_omap_port *up = (struct uart_omap_port *)port;
 573         unsigned long flags = 0;
 574
 575         dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->pdev->id);
 576
 577         pm_runtime_get_sync(&up->pdev->dev);
 578         /*
 579          * Disable interrupts from this port
 580          */
 581         up->ier = 0;
 582         serial_out(up, UART_IER, 0);
 583
 584         spin_lock_irqsave(&up->port.lock, flags);
 585         up->port.mctrl &= ~TIOCM_OUT2;
 586         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 587         spin_unlock_irqrestore(&up->port.lock, flags);
 588
 589         /*
 590          * Disable break condition and FIFOs
 591          */
 592         serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 593         serial_omap_clear_fifos(up);
 594
 595         /*
 596          * Read data port to reset things, and then free the irq
 597          */
 598         if (serial_in(up, UART_LSR) & UART_LSR_DR)
 599                 (void) serial_in(up, UART_RX);
 600         if (up->use_dma) {
 601                 dma_free_coherent(up->port.dev,
 602                         UART_XMIT_SIZE, up->port.state->xmit.buf,
 603                         up->uart_dma.tx_buf_dma_phys);
 604                 up->port.state->xmit.buf = NULL;
 605                 serial_omap_stop_rx(port);
 606                 dma_free_coherent(up->port.dev,
 607                         up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
 608                         up->uart_dma.rx_buf_dma_phys);
 609                 up->uart_dma.rx_buf = NULL;
 610         }
 611
 612         pm_runtime_put(&up->pdev->dev);
 613         free_irq(up->port.irq, up);
 614 }
 615
 616 static inline void
 617 serial_omap_configure_xonxoff
 618                 (struct uart_omap_port *up, struct ktermios *termios)
 619 {
 620         up->lcr = serial_in(up, UART_LCR);
 621         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 622         up->efr = serial_in(up, UART_EFR);
 623         serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
 624
 625         serial_out(up, UART_XON1, termios->c_cc[VSTART]);
 626         serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
 627
 628         /* clear SW control mode bits */
 629         up->efr &= OMAP_UART_SW_CLR;
 630
 631         /*
 632          * IXON Flag:
 633          * Enable XON/XOFF flow control on output.
 634          * Transmit XON1, XOFF1
 635          */
 636         if (termios->c_iflag & IXON)
 637                 up->efr |= OMAP_UART_SW_TX;
 638
 639         /*
 640          * IXOFF Flag:
 641          * Enable XON/XOFF flow control on input.
 642          * Receiver compares XON1, XOFF1.
 643          */
 644         if (termios->c_iflag & IXOFF)
 645                 up->efr |= OMAP_UART_SW_RX;
 646
 647         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 648         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 649
 650         up->mcr = serial_in(up, UART_MCR);
 651
 652         /*
 653          * IXANY Flag:
 654          * Enable any character to restart output.
 655          * Operation resumes after receiving any
 656          * character after recognition of the XOFF character
 657          */
 658         if (termios->c_iflag & IXANY)
 659                 up->mcr |= UART_MCR_XONANY;
 660
 661         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 662         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 663         serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
 664         /* Enable special char function UARTi.EFR_REG[5] and
 665          * load the new software flow control mode IXON or IXOFF
 666          * and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
 667          */
 668         serial_out(up, UART_EFR, up->efr | UART_EFR_SCD);
 669         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 670
 671         serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
 672         serial_out(up, UART_LCR, up->lcr);
 673 }
 674
 675 static void
 676 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 677                         struct ktermios *old)
 678 {
 679         struct uart_omap_port *up = (struct uart_omap_port *)port;
 680         unsigned char cval = 0;
 681         unsigned char efr = 0;
 682         unsigned long flags = 0;
 683         unsigned int baud, quot;
 684
 685         switch (termios->c_cflag & CSIZE) {
 686         case CS5:
 687                 cval = UART_LCR_WLEN5;
 688                 break;
 689         case CS6:
 690                 cval = UART_LCR_WLEN6;
 691                 break;
 692         case CS7:
 693                 cval = UART_LCR_WLEN7;
 694                 break;
 695         default:
 696         case CS8:
 697                 cval = UART_LCR_WLEN8;
 698                 break;
 699         }
 700
 701         if (termios->c_cflag & CSTOPB)
 702                 cval |= UART_LCR_STOP;
 703         if (termios->c_cflag & PARENB)
 704                 cval |= UART_LCR_PARITY;
 705         if (!(termios->c_cflag & PARODD))
 706                 cval |= UART_LCR_EPAR;
 707
 708         /*
 709          * Ask the core to calculate the divisor for us.
 710          */
 711
 712         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
 713         quot = serial_omap_get_divisor(port, baud);
 714
 715         up->dll = quot & 0xff;
 716         up->dlh = quot >> 8;
 717         up->mdr1 = UART_OMAP_MDR1_DISABLE;
 718
 719         up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
 720                         UART_FCR_ENABLE_FIFO;
 721         if (up->use_dma)
 722                 up->fcr |= UART_FCR_DMA_SELECT;
 723
 724         /*
 725          * Ok, we're now changing the port state. Do it with
 726          * interrupts disabled.
 727          */
 728         pm_runtime_get_sync(&up->pdev->dev);
 729         spin_lock_irqsave(&up->port.lock, flags);
 730
 731         /*
 732          * Update the per-port timeout.
 733          */
 734         uart_update_timeout(port, termios->c_cflag, baud);
 735
 736         up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 737         if (termios->c_iflag & INPCK)
 738                 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 739         if (termios->c_iflag & (BRKINT | PARMRK))
 740                 up->port.read_status_mask |= UART_LSR_BI;
 741
 742         /*
 743          * Characters to ignore
 744          */
 745         up->port.ignore_status_mask = 0;
 746         if (termios->c_iflag & IGNPAR)
 747                 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 748         if (termios->c_iflag & IGNBRK) {
 749                 up->port.ignore_status_mask |= UART_LSR_BI;
 750                 /*
 751                  * If we're ignoring parity and break indicators,
 752                  * ignore overruns too (for real raw support).
 753                  */
 754                 if (termios->c_iflag & IGNPAR)
 755                         up->port.ignore_status_mask |= UART_LSR_OE;
 756         }
 757
 758         /*
 759          * ignore all characters if CREAD is not set
 760          */
 761         if ((termios->c_cflag & CREAD) == 0)
 762                 up->port.ignore_status_mask |= UART_LSR_DR;
 763
 764         /*
 765          * Modem status interrupts
 766          */
 767         up->ier &= ~UART_IER_MSI;
 768         if (UART_ENABLE_MS(&up->port, termios->c_cflag))
 769                 up->ier |= UART_IER_MSI;
 770         serial_out(up, UART_IER, up->ier);
 771         serial_out(up, UART_LCR, cval);         /* reset DLAB */
 772         up->lcr = cval;
 773         up->scr = OMAP_UART_SCR_TX_EMPTY;
 774
 775         /* FIFOs and DMA Settings */
 776
 777         /* FCR can be changed only when the
 778          * baud clock is not running
 779          * DLL_REG and DLH_REG set to 0.
 780          */
 781         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 782         serial_out(up, UART_DLL, 0);
 783         serial_out(up, UART_DLM, 0);
 784         serial_out(up, UART_LCR, 0);
 785
 786         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 787
 788         up->efr = serial_in(up, UART_EFR);
 789         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 790
 791         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 792         up->mcr = serial_in(up, UART_MCR);
 793         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 794         /* FIFO ENABLE, DMA MODE */
 795         serial_out(up, UART_FCR, up->fcr);
 796         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 797
 798         if (up->use_dma) {
 799                 serial_out(up, UART_TI752_TLR, 0);
 800                 up->scr |= (UART_FCR_TRIGGER_4 | UART_FCR_TRIGGER_8);
 801         }
 802
 803         serial_out(up, UART_OMAP_SCR, up->scr);
 804
 805         serial_out(up, UART_EFR, up->efr);
 806         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 807         serial_out(up, UART_MCR, up->mcr);
 808
 809         /* Protocol, Baud Rate, and Interrupt Settings */
 810
 811         serial_out(up, UART_OMAP_MDR1, up->mdr1);
 812         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 813
 814         up->efr = serial_in(up, UART_EFR);
 815         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 816
 817         serial_out(up, UART_LCR, 0);
 818         serial_out(up, UART_IER, 0);
 819         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 820
 821         serial_out(up, UART_DLL, up->dll);      /* LS of divisor */
 822         serial_out(up, UART_DLM, up->dlh);      /* MS of divisor */
 823
 824         serial_out(up, UART_LCR, 0);
 825         serial_out(up, UART_IER, up->ier);
 826         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 827
 828         serial_out(up, UART_EFR, up->efr);
 829         serial_out(up, UART_LCR, cval);
 830
 831         if (baud > 230400 && baud != 3000000)
 832                 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
 833         else
 834                 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
 835
 836         serial_out(up, UART_OMAP_MDR1, up->mdr1);
 837
 838         /* Hardware Flow Control Configuration */
 839
 840         if (termios->c_cflag & CRTSCTS) {
 841                 efr |= (UART_EFR_CTS | UART_EFR_RTS);
 842                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 843
 844                 up->mcr = serial_in(up, UART_MCR);
 845                 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 846
 847                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 848                 up->efr = serial_in(up, UART_EFR);
 849                 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 850
 851                 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
 852                 serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
 853                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 854                 serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
 855                 serial_out(up, UART_LCR, cval);
 856         }
 857
 858         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 859         /* Software Flow Control Configuration */
 860         serial_omap_configure_xonxoff(up, termios);
 861
 862         spin_unlock_irqrestore(&up->port.lock, flags);
 863         pm_runtime_put(&up->pdev->dev);
 864         dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->pdev->id);
 865 }
 866
 867 static void
 868 serial_omap_pm(struct uart_port *port, unsigned int state,
 869                unsigned int oldstate)
 870 {
 871         struct uart_omap_port *up = (struct uart_omap_port *)port;
 872         unsigned char efr;
 873
 874         dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->pdev->id);
 875
 876         pm_runtime_get_sync(&up->pdev->dev);
 877         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 878         efr = serial_in(up, UART_EFR);
 879         serial_out(up, UART_EFR, efr | UART_EFR_ECB);
 880         serial_out(up, UART_LCR, 0);
 881
 882         serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
 883         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 884         serial_out(up, UART_EFR, efr);
 885         serial_out(up, UART_LCR, 0);
 886
 887         if (!device_may_wakeup(&up->pdev->dev)) {
 888                 if (!state)
 889                         pm_runtime_forbid(&up->pdev->dev);
 890                 else
 891                         pm_runtime_allow(&up->pdev->dev);
 892         }
 893
 894         pm_runtime_put(&up->pdev->dev);
 895 }
 896
 897 static void serial_omap_release_port(struct uart_port *port)
 898 {
 899         dev_dbg(port->dev, "serial_omap_release_port+\n");
 900 }
 901
 902 static int serial_omap_request_port(struct uart_port *port)
 903 {
 904         dev_dbg(port->dev, "serial_omap_request_port+\n");
 905         return 0;
 906 }
 907
 908 static void serial_omap_config_port(struct uart_port *port, int flags)
 909 {
 910         struct uart_omap_port *up = (struct uart_omap_port *)port;
 911
 912         dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
 913                                                         up->pdev->id);
 914         up->port.type = PORT_OMAP;
 915 }
 916
 917 static int
 918 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
 919 {
 920         /* we don't want the core code to modify any port params */
 921         dev_dbg(port->dev, "serial_omap_verify_port+\n");
 922         return -EINVAL;
 923 }
 924
 925 static const char *
 926 serial_omap_type(struct uart_port *port)
 927 {
 928         struct uart_omap_port *up = (struct uart_omap_port *)port;
 929
 930         dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->pdev->id);
 931         return up->name;
 932 }
 933
 934 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
 935
 936 static inline void wait_for_xmitr(struct uart_omap_port *up)
 937 {
 938         unsigned int status, tmout = 10000;
 939
 940         /* Wait up to 10ms for the character(s) to be sent. */
 941         do {
 942                 status = serial_in(up, UART_LSR);
 943
 944                 if (status & UART_LSR_BI)
 945                         up->lsr_break_flag = UART_LSR_BI;
 946
 947                 if (--tmout == 0)
 948                         break;
 949                 udelay(1);
 950         } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
 951
 952         /* Wait up to 1s for flow control if necessary */
 953         if (up->port.flags & UPF_CONS_FLOW) {
 954                 tmout = 1000000;
 955                 for (tmout = 1000000; tmout; tmout--) {
 956                         unsigned int msr = serial_in(up, UART_MSR);
 957
 958                         up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
 959                         if (msr & UART_MSR_CTS)
 960                                 break;
 961
 962                         udelay(1);
 963                 }
 964         }
 965 }
 966
 967 #ifdef CONFIG_CONSOLE_POLL
 968
 969 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
 970 {
 971         struct uart_omap_port *up = (struct uart_omap_port *)port;
 972
 973         pm_runtime_get_sync(&up->pdev->dev);
 974         wait_for_xmitr(up);
 975         serial_out(up, UART_TX, ch);
 976         pm_runtime_put(&up->pdev->dev);
 977 }
 978
 979 static int serial_omap_poll_get_char(struct uart_port *port)
 980 {
 981         struct uart_omap_port *up = (struct uart_omap_port *)port;
 982         unsigned int status;
 983
 984         pm_runtime_get_sync(&up->pdev->dev);
 985         status = serial_in(up, UART_LSR);
 986         if (!(status & UART_LSR_DR))
 987                 return NO_POLL_CHAR;
 988
 989         status = serial_in(up, UART_RX);
 990         pm_runtime_put(&up->pdev->dev);
 991         return status;
 992 }
 993
 994 #endif /* CONFIG_CONSOLE_POLL */
 995
 996 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
 997
 998 static struct uart_omap_port *serial_omap_console_ports[4];
 999
1000 static struct uart_driver serial_omap_reg;
1001
1002 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1003 {
1004         struct uart_omap_port *up = (struct uart_omap_port *)port;
1005
1006         wait_for_xmitr(up);
1007         serial_out(up, UART_TX, ch);
1008 }
1009
1010 static void
1011 serial_omap_console_write(struct console *co, const char *s,
1012                 unsigned int count)
1013 {
1014         struct uart_omap_port *up = serial_omap_console_ports[co->index];
1015         unsigned long flags;
1016         unsigned int ier;
1017         int locked = 1;
1018
1019         pm_runtime_get_sync(&up->pdev->dev);
1020
1021         local_irq_save(flags);
1022         if (up->port.sysrq)
1023                 locked = 0;
1024         else if (oops_in_progress)
1025                 locked = spin_trylock(&up->port.lock);
1026         else
1027                 spin_lock(&up->port.lock);
1028
1029         /*
1030          * First save the IER then disable the interrupts
1031          */
1032         ier = serial_in(up, UART_IER);
1033         serial_out(up, UART_IER, 0);
1034
1035         uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1036
1037         /*
1038          * Finally, wait for transmitter to become empty
1039          * and restore the IER
1040          */
1041         wait_for_xmitr(up);
1042         serial_out(up, UART_IER, ier);
1043         /*
1044          * The receive handling will happen properly because the
1045          * receive ready bit will still be set; it is not cleared
1046          * on read.  However, modem control will not, we must
1047          * call it if we have saved something in the saved flags
1048          * while processing with interrupts off.
1049          */
1050         if (up->msr_saved_flags)
1051                 check_modem_status(up);
1052
1053         pm_runtime_mark_last_busy(&up->pdev->dev);
1054         pm_runtime_put_autosuspend(&up->pdev->dev);
1055         if (locked)
1056                 spin_unlock(&up->port.lock);
1057         local_irq_restore(flags);
1058 }
1059
1060 static int __init
1061 serial_omap_console_setup(struct console *co, char *options)
1062 {
1063         struct uart_omap_port *up;
1064         int baud = 115200;
1065         int bits = 8;
1066         int parity = 'n';
1067         int flow = 'n';
1068
1069         if (serial_omap_console_ports[co->index] == NULL)
1070                 return -ENODEV;
1071         up = serial_omap_console_ports[co->index];
1072
1073         if (options)
1074                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1075
1076         return uart_set_options(&up->port, co, baud, parity, bits, flow);
1077 }
1078
1079 static struct console serial_omap_console = {
1080         .name           = OMAP_SERIAL_NAME,
1081         .write          = serial_omap_console_write,
1082         .device         = uart_console_device,
1083         .setup          = serial_omap_console_setup,
1084         .flags          = CON_PRINTBUFFER,
1085         .index          = -1,
1086         .data           = &serial_omap_reg,
1087 };
1088
1089 static void serial_omap_add_console_port(struct uart_omap_port *up)
1090 {
1091         serial_omap_console_ports[up->pdev->id] = up;
1092 }
1093
1094 #define OMAP_CONSOLE    (&serial_omap_console)
1095
1096 #else
1097
1098 #define OMAP_CONSOLE    NULL
1099
1100 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1101 {}
1102
1103 #endif
1104
1105 static struct uart_ops serial_omap_pops = {
1106         .tx_empty       = serial_omap_tx_empty,
1107         .set_mctrl      = serial_omap_set_mctrl,
1108         .get_mctrl      = serial_omap_get_mctrl,
1109         .stop_tx        = serial_omap_stop_tx,
1110         .start_tx       = serial_omap_start_tx,
1111         .stop_rx        = serial_omap_stop_rx,
1112         .enable_ms      = serial_omap_enable_ms,
1113         .break_ctl      = serial_omap_break_ctl,
1114         .startup        = serial_omap_startup,
1115         .shutdown       = serial_omap_shutdown,
1116         .set_termios    = serial_omap_set_termios,
1117         .pm             = serial_omap_pm,
1118         .type           = serial_omap_type,
1119         .release_port   = serial_omap_release_port,
1120         .request_port   = serial_omap_request_port,
1121         .config_port    = serial_omap_config_port,
1122         .verify_port    = serial_omap_verify_port,
1123 #ifdef CONFIG_CONSOLE_POLL
1124         .poll_put_char  = serial_omap_poll_put_char,
1125         .poll_get_char  = serial_omap_poll_get_char,
1126 #endif
1127 };
1128
1129 static struct uart_driver serial_omap_reg = {
1130         .owner          = THIS_MODULE,
1131         .driver_name    = "OMAP-SERIAL",
1132         .dev_name       = OMAP_SERIAL_NAME,
1133         .nr             = OMAP_MAX_HSUART_PORTS,
1134         .cons           = OMAP_CONSOLE,
1135 };
1136
1137 #ifdef CONFIG_SUSPEND
1138 static int serial_omap_suspend(struct device *dev)
1139 {
1140         struct uart_omap_port *up = dev_get_drvdata(dev);
1141
1142         if (up)
1143                 uart_suspend_port(&serial_omap_reg, &up->port);
1144         return 0;
1145 }
1146
1147 static int serial_omap_resume(struct device *dev)
1148 {
1149         struct uart_omap_port *up = dev_get_drvdata(dev);
1150
1151         if (up)
1152                 uart_resume_port(&serial_omap_reg, &up->port);
1153         return 0;
1154 }
1155 #endif
1156
1157 static void serial_omap_rx_timeout(unsigned long uart_no)
1158 {
1159         struct uart_omap_port *up = ui[uart_no];
1160         unsigned int curr_dma_pos, curr_transmitted_size;
1161         int ret = 0;
1162
1163         curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
1164         if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
1165                              (curr_dma_pos == 0)) {
1166                 if (jiffies_to_msecs(jiffies - up->port_activity) <
1167                                                         RX_TIMEOUT) {
1168                         mod_timer(&up->uart_dma.rx_timer, jiffies +
1169                                 usecs_to_jiffies(up->uart_dma.rx_timeout));
1170                 } else {
1171                         serial_omap_stop_rxdma(up);
1172                         up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1173                         serial_out(up, UART_IER, up->ier);
1174                 }
1175                 return;
1176         }
1177
1178         curr_transmitted_size = curr_dma_pos -
1179                                         up->uart_dma.prev_rx_dma_pos;
1180         up->port.icount.rx += curr_transmitted_size;
1181         tty_insert_flip_string(up->port.state->port.tty,
1182                         up->uart_dma.rx_buf +
1183                         (up->uart_dma.prev_rx_dma_pos -
1184                         up->uart_dma.rx_buf_dma_phys),
1185                         curr_transmitted_size);
1186         tty_flip_buffer_push(up->port.state->port.tty);
1187         up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
1188         if (up->uart_dma.rx_buf_size +
1189                         up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
1190                 ret = serial_omap_start_rxdma(up);
1191                 if (ret < 0) {
1192                         serial_omap_stop_rxdma(up);
1193                         up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1194                         serial_out(up, UART_IER, up->ier);
1195                 }
1196         } else  {
1197                 mod_timer(&up->uart_dma.rx_timer, jiffies +
1198                         usecs_to_jiffies(up->uart_dma.rx_timeout));
1199         }
1200         up->port_activity = jiffies;
1201 }
1202
1203 static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
1204 {
1205         return;
1206 }
1207
1208 static int serial_omap_start_rxdma(struct uart_omap_port *up)
1209 {
1210         int ret = 0;
1211
1212         if (up->uart_dma.rx_dma_channel == -1) {
1213                 pm_runtime_get_sync(&up->pdev->dev);
1214                 ret = omap_request_dma(up->uart_dma.uart_dma_rx,
1215                                 "UART Rx DMA",
1216                                 (void *)uart_rx_dma_callback, up,
1217                                 &(up->uart_dma.rx_dma_channel));
1218                 if (ret < 0)
1219                         return ret;
1220
1221                 omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
1222                                 OMAP_DMA_AMODE_CONSTANT,
1223                                 up->uart_dma.uart_base, 0, 0);
1224                 omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
1225                                 OMAP_DMA_AMODE_POST_INC,
1226                                 up->uart_dma.rx_buf_dma_phys, 0, 0);
1227                 omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
1228                                 OMAP_DMA_DATA_TYPE_S8,
1229                                 up->uart_dma.rx_buf_size, 1,
1230                                 OMAP_DMA_SYNC_ELEMENT,
1231                                 up->uart_dma.uart_dma_rx, 0);
1232         }
1233         up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
1234         /* FIXME: Cache maintenance needed here? */
1235         omap_start_dma(up->uart_dma.rx_dma_channel);
1236         mod_timer(&up->uart_dma.rx_timer, jiffies +
1237                                 usecs_to_jiffies(up->uart_dma.rx_timeout));
1238         up->uart_dma.rx_dma_used = true;
1239         return ret;
1240 }
1241
1242 static void serial_omap_continue_tx(struct uart_omap_port *up)
1243 {
1244         struct circ_buf *xmit = &up->port.state->xmit;
1245         unsigned int start = up->uart_dma.tx_buf_dma_phys
1246                         + (xmit->tail & (UART_XMIT_SIZE - 1));
1247
1248         if (uart_circ_empty(xmit))
1249                 return;
1250
1251         up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
1252         /*
1253          * It is a circular buffer. See if the buffer has wounded back.
1254          * If yes it will have to be transferred in two separate dma
1255          * transfers
1256          */
1257         if (start + up->uart_dma.tx_buf_size >=
1258                         up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
1259                 up->uart_dma.tx_buf_size =
1260                         (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
1261         omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
1262                                 OMAP_DMA_AMODE_CONSTANT,
1263                                 up->uart_dma.uart_base, 0, 0);
1264         omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
1265                                 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
1266         omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
1267                                 OMAP_DMA_DATA_TYPE_S8,
1268                                 up->uart_dma.tx_buf_size, 1,
1269                                 OMAP_DMA_SYNC_ELEMENT,
1270                                 up->uart_dma.uart_dma_tx, 0);
1271         /* FIXME: Cache maintenance needed here? */
1272         omap_start_dma(up->uart_dma.tx_dma_channel);
1273 }
1274
1275 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
1276 {
1277         struct uart_omap_port *up = (struct uart_omap_port *)data;
1278         struct circ_buf *xmit = &up->port.state->xmit;
1279
1280         xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
1281                         (UART_XMIT_SIZE - 1);
1282         up->port.icount.tx += up->uart_dma.tx_buf_size;
1283
1284         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1285                 uart_write_wakeup(&up->port);
1286
1287         if (uart_circ_empty(xmit)) {
1288                 spin_lock(&(up->uart_dma.tx_lock));
1289                 serial_omap_stop_tx(&up->port);
1290                 up->uart_dma.tx_dma_used = false;
1291                 spin_unlock(&(up->uart_dma.tx_lock));
1292         } else {
1293                 omap_stop_dma(up->uart_dma.tx_dma_channel);
1294                 serial_omap_continue_tx(up);
1295         }
1296         up->port_activity = jiffies;
1297         return;
1298 }
1299
1300 static int serial_omap_probe(struct platform_device *pdev)
1301 {
1302         struct uart_omap_port   *up;
1303         struct resource         *mem, *irq, *dma_tx, *dma_rx;
1304         struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1305         int ret = -ENOSPC;
1306
1307         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1308         if (!mem) {
1309                 dev_err(&pdev->dev, "no mem resource?\n");
1310                 return -ENODEV;
1311         }
1312
1313         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1314         if (!irq) {
1315                 dev_err(&pdev->dev, "no irq resource?\n");
1316                 return -ENODEV;
1317         }
1318
1319         if (!request_mem_region(mem->start, resource_size(mem),
1320                                 pdev->dev.driver->name)) {
1321                 dev_err(&pdev->dev, "memory region already claimed\n");
1322                 return -EBUSY;
1323         }
1324
1325         dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1326         if (!dma_rx) {
1327                 ret = -EINVAL;
1328                 goto err;
1329         }
1330
1331         dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1332         if (!dma_tx) {
1333                 ret = -EINVAL;
1334                 goto err;
1335         }
1336
1337         up = kzalloc(sizeof(*up), GFP_KERNEL);
1338         if (up == NULL) {
1339                 ret = -ENOMEM;
1340                 goto do_release_region;
1341         }
1342         sprintf(up->name, "OMAP UART%d", pdev->id);
1343         up->pdev = pdev;
1344         up->port.dev = &pdev->dev;
1345         up->port.type = PORT_OMAP;
1346         up->port.iotype = UPIO_MEM;
1347         up->port.irq = irq->start;
1348
1349         up->port.regshift = 2;
1350         up->port.fifosize = 64;
1351         up->port.ops = &serial_omap_pops;
1352         up->port.line = pdev->id;
1353
1354         up->port.mapbase = mem->start;
1355         up->port.membase = ioremap(mem->start, resource_size(mem));
1356         if (!up->port.membase) {
1357                 dev_err(&pdev->dev, "can't ioremap UART\n");
1358                 ret = -ENOMEM;
1359                 goto err;
1360         }
1361
1362         up->port.flags = omap_up_info->flags;
1363         up->port.uartclk = omap_up_info->uartclk;
1364         up->uart_dma.uart_base = mem->start;
1365
1366         if (omap_up_info->dma_enabled) {
1367                 up->uart_dma.uart_dma_tx = dma_tx->start;
1368                 up->uart_dma.uart_dma_rx = dma_rx->start;
1369                 up->use_dma = 1;
1370                 up->uart_dma.rx_buf_size = 4096;
1371                 up->uart_dma.rx_timeout = 2;
1372                 spin_lock_init(&(up->uart_dma.tx_lock));
1373                 spin_lock_init(&(up->uart_dma.rx_lock));
1374                 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
1375                 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
1376         }
1377
1378         pm_runtime_use_autosuspend(&pdev->dev);
1379         pm_runtime_set_autosuspend_delay(&pdev->dev,
1380                         OMAP_UART_AUTOSUSPEND_DELAY);
1381
1382         pm_runtime_irq_safe(&pdev->dev);
1383         pm_runtime_enable(&pdev->dev);
1384         pm_runtime_get_sync(&pdev->dev);
1385
1386         ui[pdev->id] = up;
1387         serial_omap_add_console_port(up);
1388
1389         ret = uart_add_one_port(&serial_omap_reg, &up->port);
1390         if (ret != 0)
1391                 goto do_release_region;
1392
1393         pm_runtime_put(&pdev->dev);
1394         platform_set_drvdata(pdev, up);
1395         return 0;
1396 err:
1397         dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1398                                 pdev->id, __func__, ret);
1399 do_release_region:
1400         release_mem_region(mem->start, resource_size(mem));
1401         return ret;
1402 }
1403
1404 static int serial_omap_remove(struct platform_device *dev)
1405 {
1406         struct uart_omap_port *up = platform_get_drvdata(dev);
1407
1408         if (up) {
1409                 pm_runtime_disable(&up->pdev->dev);
1410                 uart_remove_one_port(&serial_omap_reg, &up->port);
1411                 kfree(up);
1412         }
1413
1414         platform_set_drvdata(dev, NULL);
1415         return 0;
1416 }
1417
1418 static void serial_omap_restore_context(struct uart_omap_port *up)
1419 {
1420         serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1421         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1422         serial_out(up, UART_EFR, UART_EFR_ECB);
1423         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1424         serial_out(up, UART_IER, 0x0);
1425         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1426         serial_out(up, UART_DLL, up->dll);
1427         serial_out(up, UART_DLM, up->dlh);
1428         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1429         serial_out(up, UART_IER, up->ier);
1430         serial_out(up, UART_FCR, up->fcr);
1431         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1432         serial_out(up, UART_MCR, up->mcr);
1433         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1434         serial_out(up, UART_OMAP_SCR, up->scr);
1435         serial_out(up, UART_EFR, up->efr);
1436         serial_out(up, UART_LCR, up->lcr);
1437         serial_out(up, UART_OMAP_MDR1, up->mdr1);
1438 }
1439
1440 #ifdef CONFIG_PM_RUNTIME
1441 static int serial_omap_runtime_suspend(struct device *dev)
1442 {
1443         struct uart_omap_port *up = dev_get_drvdata(dev);
1444         struct omap_uart_port_info *pdata = dev->platform_data;
1445
1446         if (!up)
1447                 return -EINVAL;
1448
1449         if (pdata->get_context_loss_count)
1450                 up->context_loss_cnt = pdata->get_context_loss_count(dev);
1451
1452         return 0;
1453 }
1454
1455 static int serial_omap_runtime_resume(struct device *dev)
1456 {
1457         struct uart_omap_port *up = dev_get_drvdata(dev);
1458         struct omap_uart_port_info *pdata = dev->platform_data;
1459
1460         if (up) {
1461                 if (pdata->get_context_loss_count) {
1462                         u32 loss_cnt = pdata->get_context_loss_count(dev);
1463
1464                         if (up->context_loss_cnt != loss_cnt)
1465                                 serial_omap_restore_context(up);
1466                 }
1467         }
1468
1469         return 0;
1470 }
1471 #endif
1472
1473 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1474         SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1475         SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1476                                 serial_omap_runtime_resume, NULL)
1477 };
1478
1479 static struct platform_driver serial_omap_driver = {
1480         .probe          = serial_omap_probe,
1481         .remove         = serial_omap_remove,
1482         .driver         = {
1483                 .name   = DRIVER_NAME,
1484                 .pm     = &serial_omap_dev_pm_ops,
1485         },
1486 };
1487
1488 static int __init serial_omap_init(void)
1489 {
1490         int ret;
1491
1492         ret = uart_register_driver(&serial_omap_reg);
1493         if (ret != 0)
1494                 return ret;
1495         ret = platform_driver_register(&serial_omap_driver);
1496         if (ret != 0)
1497                 uart_unregister_driver(&serial_omap_reg);
1498         return ret;
1499 }
1500
1501 static void __exit serial_omap_exit(void)
1502 {
1503         platform_driver_unregister(&serial_omap_driver);
1504         uart_unregister_driver(&serial_omap_reg);
1505 }
1506
1507 module_init(serial_omap_init);
1508 module_exit(serial_omap_exit);
1509
1510 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1511 MODULE_LICENSE("GPL");
1512 MODULE_AUTHOR("Texas Instruments Inc");