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 #include <linux/of.h>
  42
  43 #include <plat/dma.h>
  44 #include <plat/dmtimer.h>
  45 #include <plat/omap-serial.h>
  46
  47 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
  48
  49 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
  50
  51 /* Forward declaration of functions */
  52 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
  53 static void serial_omap_rxdma_poll(unsigned long uart_no);
  54 static int serial_omap_start_rxdma(struct uart_omap_port *up);
  55 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
  56
  57 static struct workqueue_struct *serial_omap_uart_wq;
  58
  59 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
  60 {
  61         offset <<= up->port.regshift;
  62         return readw(up->port.membase + offset);
  63 }
  64
  65 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
  66 {
  67         offset <<= up->port.regshift;
  68         writew(value, up->port.membase + offset);
  69 }
  70
  71 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
  72 {
  73         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
  74         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
  75                        UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
  76         serial_out(up, UART_FCR, 0);
  77 }
  78
  79 /*
  80  * serial_omap_get_divisor - calculate divisor value
  81  * @port: uart port info
  82  * @baud: baudrate for which divisor needs to be calculated.
  83  *
  84  * We have written our own function to get the divisor so as to support
  85  * 13x mode. 3Mbps Baudrate as an different divisor.
  86  * Reference OMAP TRM Chapter 17:
  87  * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
  88  * referring to oversampling - divisor value
  89  * baudrate 460,800 to 3,686,400 all have divisor 13
  90  * except 3,000,000 which has divisor value 16
  91  */
  92 static unsigned int
  93 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
  94 {
  95         unsigned int divisor;
  96
  97         if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
  98                 divisor = 13;
  99         else
 100                 divisor = 16;
 101         return port->uartclk/(baud * divisor);
 102 }
 103
 104 static void serial_omap_stop_rxdma(struct uart_omap_port *up)
 105 {
 106         if (up->uart_dma.rx_dma_used) {
 107                 del_timer(&up->uart_dma.rx_timer);
 108                 omap_stop_dma(up->uart_dma.rx_dma_channel);
 109                 omap_free_dma(up->uart_dma.rx_dma_channel);
 110                 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
 111                 up->uart_dma.rx_dma_used = false;
 112                 pm_runtime_mark_last_busy(&up->pdev->dev);
 113                 pm_runtime_put_autosuspend(&up->pdev->dev);
 114         }
 115 }
 116
 117 static void serial_omap_enable_ms(struct uart_port *port)
 118 {
 119         struct uart_omap_port *up = (struct uart_omap_port *)port;
 120
 121         dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
 122
 123         pm_runtime_get_sync(&up->pdev->dev);
 124         up->ier |= UART_IER_MSI;
 125         serial_out(up, UART_IER, up->ier);
 126         pm_runtime_put(&up->pdev->dev);
 127 }
 128
 129 static void serial_omap_stop_tx(struct uart_port *port)
 130 {
 131         struct uart_omap_port *up = (struct uart_omap_port *)port;
 132
 133         if (up->use_dma &&
 134                 up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
 135                 /*
 136                  * Check if dma is still active. If yes do nothing,
 137                  * return. Else stop dma
 138                  */
 139                 if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
 140                         return;
 141                 omap_stop_dma(up->uart_dma.tx_dma_channel);
 142                 omap_free_dma(up->uart_dma.tx_dma_channel);
 143                 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
 144                 pm_runtime_mark_last_busy(&up->pdev->dev);
 145                 pm_runtime_put_autosuspend(&up->pdev->dev);
 146         }
 147
 148         pm_runtime_get_sync(&up->pdev->dev);
 149         if (up->ier & UART_IER_THRI) {
 150                 up->ier &= ~UART_IER_THRI;
 151                 serial_out(up, UART_IER, up->ier);
 152         }
 153
 154         pm_runtime_mark_last_busy(&up->pdev->dev);
 155         pm_runtime_put_autosuspend(&up->pdev->dev);
 156 }
 157
 158 static void serial_omap_stop_rx(struct uart_port *port)
 159 {
 160         struct uart_omap_port *up = (struct uart_omap_port *)port;
 161
 162         pm_runtime_get_sync(&up->pdev->dev);
 163         if (up->use_dma)
 164                 serial_omap_stop_rxdma(up);
 165         up->ier &= ~UART_IER_RLSI;
 166         up->port.read_status_mask &= ~UART_LSR_DR;
 167         serial_out(up, UART_IER, up->ier);
 168         pm_runtime_mark_last_busy(&up->pdev->dev);
 169         pm_runtime_put_autosuspend(&up->pdev->dev);
 170 }
 171
 172 static inline void receive_chars(struct uart_omap_port *up,
 173                 unsigned int *status)
 174 {
 175         struct tty_struct *tty = up->port.state->port.tty;
 176         unsigned int flag, lsr = *status;
 177         unsigned char ch = 0;
 178         int max_count = 256;
 179
 180         do {
 181                 if (likely(lsr & UART_LSR_DR))
 182                         ch = serial_in(up, UART_RX);
 183                 flag = TTY_NORMAL;
 184                 up->port.icount.rx++;
 185
 186                 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
 187                         /*
 188                          * For statistics only
 189                          */
 190                         if (lsr & UART_LSR_BI) {
 191                                 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
 192                                 up->port.icount.brk++;
 193                                 /*
 194                                  * We do the SysRQ and SAK checking
 195                                  * here because otherwise the break
 196                                  * may get masked by ignore_status_mask
 197                                  * or read_status_mask.
 198                                  */
 199                                 if (uart_handle_break(&up->port))
 200                                         goto ignore_char;
 201                         } else if (lsr & UART_LSR_PE) {
 202                                 up->port.icount.parity++;
 203                         } else if (lsr & UART_LSR_FE) {
 204                                 up->port.icount.frame++;
 205                         }
 206
 207                         if (lsr & UART_LSR_OE)
 208                                 up->port.icount.overrun++;
 209
 210                         /*
 211                          * Mask off conditions which should be ignored.
 212                          */
 213                         lsr &= up->port.read_status_mask;
 214
 215 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
 216                         if (up->port.line == up->port.cons->index) {
 217                                 /* Recover the break flag from console xmit */
 218                                 lsr |= up->lsr_break_flag;
 219                         }
 220 #endif
 221                         if (lsr & UART_LSR_BI)
 222                                 flag = TTY_BREAK;
 223                         else if (lsr & UART_LSR_PE)
 224                                 flag = TTY_PARITY;
 225                         else if (lsr & UART_LSR_FE)
 226                                 flag = TTY_FRAME;
 227                 }
 228
 229                 if (uart_handle_sysrq_char(&up->port, ch))
 230                         goto ignore_char;
 231                 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
 232 ignore_char:
 233                 lsr = serial_in(up, UART_LSR);
 234         } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
 235         spin_unlock(&up->port.lock);
 236         tty_flip_buffer_push(tty);
 237         spin_lock(&up->port.lock);
 238 }
 239
 240 static void transmit_chars(struct uart_omap_port *up)
 241 {
 242         struct circ_buf *xmit = &up->port.state->xmit;
 243         int count;
 244
 245         if (up->port.x_char) {
 246                 serial_out(up, UART_TX, up->port.x_char);
 247                 up->port.icount.tx++;
 248                 up->port.x_char = 0;
 249                 return;
 250         }
 251         if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 252                 serial_omap_stop_tx(&up->port);
 253                 return;
 254         }
 255         count = up->port.fifosize / 4;
 256         do {
 257                 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 258                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 259                 up->port.icount.tx++;
 260                 if (uart_circ_empty(xmit))
 261                         break;
 262         } while (--count > 0);
 263
 264         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 265                 uart_write_wakeup(&up->port);
 266
 267         if (uart_circ_empty(xmit))
 268                 serial_omap_stop_tx(&up->port);
 269 }
 270
 271 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
 272 {
 273         if (!(up->ier & UART_IER_THRI)) {
 274                 up->ier |= UART_IER_THRI;
 275                 serial_out(up, UART_IER, up->ier);
 276         }
 277 }
 278
 279 static void serial_omap_start_tx(struct uart_port *port)
 280 {
 281         struct uart_omap_port *up = (struct uart_omap_port *)port;
 282         struct circ_buf *xmit;
 283         unsigned int start;
 284         int ret = 0;
 285
 286         if (!up->use_dma) {
 287                 pm_runtime_get_sync(&up->pdev->dev);
 288                 serial_omap_enable_ier_thri(up);
 289                 pm_runtime_mark_last_busy(&up->pdev->dev);
 290                 pm_runtime_put_autosuspend(&up->pdev->dev);
 291                 return;
 292         }
 293
 294         if (up->uart_dma.tx_dma_used)
 295                 return;
 296
 297         xmit = &up->port.state->xmit;
 298
 299         if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
 300                 pm_runtime_get_sync(&up->pdev->dev);
 301                 ret = omap_request_dma(up->uart_dma.uart_dma_tx,
 302                                 "UART Tx DMA",
 303                                 (void *)uart_tx_dma_callback, up,
 304                                 &(up->uart_dma.tx_dma_channel));
 305
 306                 if (ret < 0) {
 307                         serial_omap_enable_ier_thri(up);
 308                         return;
 309                 }
 310         }
 311         spin_lock(&(up->uart_dma.tx_lock));
 312         up->uart_dma.tx_dma_used = true;
 313         spin_unlock(&(up->uart_dma.tx_lock));
 314
 315         start = up->uart_dma.tx_buf_dma_phys +
 316                                 (xmit->tail & (UART_XMIT_SIZE - 1));
 317
 318         up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
 319         /*
 320          * It is a circular buffer. See if the buffer has wounded back.
 321          * If yes it will have to be transferred in two separate dma
 322          * transfers
 323          */
 324         if (start + up->uart_dma.tx_buf_size >=
 325                         up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
 326                 up->uart_dma.tx_buf_size =
 327                         (up->uart_dma.tx_buf_dma_phys +
 328                         UART_XMIT_SIZE) - start;
 329
 330         omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
 331                                 OMAP_DMA_AMODE_CONSTANT,
 332                                 up->uart_dma.uart_base, 0, 0);
 333         omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
 334                                 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
 335         omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
 336                                 OMAP_DMA_DATA_TYPE_S8,
 337                                 up->uart_dma.tx_buf_size, 1,
 338                                 OMAP_DMA_SYNC_ELEMENT,
 339                                 up->uart_dma.uart_dma_tx, 0);
 340         /* FIXME: Cache maintenance needed here? */
 341         omap_start_dma(up->uart_dma.tx_dma_channel);
 342 }
 343
 344 static unsigned int check_modem_status(struct uart_omap_port *up)
 345 {
 346         unsigned int status;
 347
 348         status = serial_in(up, UART_MSR);
 349         status |= up->msr_saved_flags;
 350         up->msr_saved_flags = 0;
 351         if ((status & UART_MSR_ANY_DELTA) == 0)
 352                 return status;
 353
 354         if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
 355             up->port.state != NULL) {
 356                 if (status & UART_MSR_TERI)
 357                         up->port.icount.rng++;
 358                 if (status & UART_MSR_DDSR)
 359                         up->port.icount.dsr++;
 360                 if (status & UART_MSR_DDCD)
 361                         uart_handle_dcd_change
 362                                 (&up->port, status & UART_MSR_DCD);
 363                 if (status & UART_MSR_DCTS)
 364                         uart_handle_cts_change
 365                                 (&up->port, status & UART_MSR_CTS);
 366                 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 367         }
 368
 369         return status;
 370 }
 371
 372 /**
 373  * serial_omap_irq() - This handles the interrupt from one port
 374  * @irq: uart port irq number
 375  * @dev_id: uart port info
 376  */
 377 static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
 378 {
 379         struct uart_omap_port *up = dev_id;
 380         unsigned int iir, lsr;
 381         unsigned long flags;
 382
 383         pm_runtime_get_sync(&up->pdev->dev);
 384         iir = serial_in(up, UART_IIR);
 385         if (iir & UART_IIR_NO_INT) {
 386                 pm_runtime_mark_last_busy(&up->pdev->dev);
 387                 pm_runtime_put_autosuspend(&up->pdev->dev);
 388                 return IRQ_NONE;
 389         }
 390
 391         spin_lock_irqsave(&up->port.lock, flags);
 392         lsr = serial_in(up, UART_LSR);
 393         if (iir & UART_IIR_RLSI) {
 394                 if (!up->use_dma) {
 395                         if (lsr & UART_LSR_DR)
 396                                 receive_chars(up, &lsr);
 397                 } else {
 398                         up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
 399                         serial_out(up, UART_IER, up->ier);
 400                         if ((serial_omap_start_rxdma(up) != 0) &&
 401                                         (lsr & UART_LSR_DR))
 402                                 receive_chars(up, &lsr);
 403                 }
 404         }
 405
 406         check_modem_status(up);
 407         if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
 408                 transmit_chars(up);
 409
 410         spin_unlock_irqrestore(&up->port.lock, flags);
 411         pm_runtime_mark_last_busy(&up->pdev->dev);
 412         pm_runtime_put_autosuspend(&up->pdev->dev);
 413
 414         up->port_activity = jiffies;
 415         return IRQ_HANDLED;
 416 }
 417
 418 static unsigned int serial_omap_tx_empty(struct uart_port *port)
 419 {
 420         struct uart_omap_port *up = (struct uart_omap_port *)port;
 421         unsigned long flags = 0;
 422         unsigned int ret = 0;
 423
 424         pm_runtime_get_sync(&up->pdev->dev);
 425         dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
 426         spin_lock_irqsave(&up->port.lock, flags);
 427         ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 428         spin_unlock_irqrestore(&up->port.lock, flags);
 429         pm_runtime_put(&up->pdev->dev);
 430         return ret;
 431 }
 432
 433 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
 434 {
 435         struct uart_omap_port *up = (struct uart_omap_port *)port;
 436         unsigned int status;
 437         unsigned int ret = 0;
 438
 439         pm_runtime_get_sync(&up->pdev->dev);
 440         status = check_modem_status(up);
 441         pm_runtime_put(&up->pdev->dev);
 442
 443         dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
 444
 445         if (status & UART_MSR_DCD)
 446                 ret |= TIOCM_CAR;
 447         if (status & UART_MSR_RI)
 448                 ret |= TIOCM_RNG;
 449         if (status & UART_MSR_DSR)
 450                 ret |= TIOCM_DSR;
 451         if (status & UART_MSR_CTS)
 452                 ret |= TIOCM_CTS;
 453         return ret;
 454 }
 455
 456 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 457 {
 458         struct uart_omap_port *up = (struct uart_omap_port *)port;
 459         unsigned char mcr = 0;
 460
 461         dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
 462         if (mctrl & TIOCM_RTS)
 463                 mcr |= UART_MCR_RTS;
 464         if (mctrl & TIOCM_DTR)
 465                 mcr |= UART_MCR_DTR;
 466         if (mctrl & TIOCM_OUT1)
 467                 mcr |= UART_MCR_OUT1;
 468         if (mctrl & TIOCM_OUT2)
 469                 mcr |= UART_MCR_OUT2;
 470         if (mctrl & TIOCM_LOOP)
 471                 mcr |= UART_MCR_LOOP;
 472
 473         pm_runtime_get_sync(&up->pdev->dev);
 474         up->mcr = serial_in(up, UART_MCR);
 475         up->mcr |= mcr;
 476         serial_out(up, UART_MCR, up->mcr);
 477         pm_runtime_put(&up->pdev->dev);
 478 }
 479
 480 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
 481 {
 482         struct uart_omap_port *up = (struct uart_omap_port *)port;
 483         unsigned long flags = 0;
 484
 485         dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
 486         pm_runtime_get_sync(&up->pdev->dev);
 487         spin_lock_irqsave(&up->port.lock, flags);
 488         if (break_state == -1)
 489                 up->lcr |= UART_LCR_SBC;
 490         else
 491                 up->lcr &= ~UART_LCR_SBC;
 492         serial_out(up, UART_LCR, up->lcr);
 493         spin_unlock_irqrestore(&up->port.lock, flags);
 494         pm_runtime_put(&up->pdev->dev);
 495 }
 496
 497 static int serial_omap_startup(struct uart_port *port)
 498 {
 499         struct uart_omap_port *up = (struct uart_omap_port *)port;
 500         unsigned long flags = 0;
 501         int retval;
 502
 503         /*
 504          * Allocate the IRQ
 505          */
 506         retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
 507                                 up->name, up);
 508         if (retval)
 509                 return retval;
 510
 511         dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
 512
 513         pm_runtime_get_sync(&up->pdev->dev);
 514         /*
 515          * Clear the FIFO buffers and disable them.
 516          * (they will be reenabled in set_termios())
 517          */
 518         serial_omap_clear_fifos(up);
 519         /* For Hardware flow control */
 520         serial_out(up, UART_MCR, UART_MCR_RTS);
 521
 522         /*
 523          * Clear the interrupt registers.
 524          */
 525         (void) serial_in(up, UART_LSR);
 526         if (serial_in(up, UART_LSR) & UART_LSR_DR)
 527                 (void) serial_in(up, UART_RX);
 528         (void) serial_in(up, UART_IIR);
 529         (void) serial_in(up, UART_MSR);
 530
 531         /*
 532          * Now, initialize the UART
 533          */
 534         serial_out(up, UART_LCR, UART_LCR_WLEN8);
 535         spin_lock_irqsave(&up->port.lock, flags);
 536         /*
 537          * Most PC uarts need OUT2 raised to enable interrupts.
 538          */
 539         up->port.mctrl |= TIOCM_OUT2;
 540         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 541         spin_unlock_irqrestore(&up->port.lock, flags);
 542
 543         up->msr_saved_flags = 0;
 544         if (up->use_dma) {
 545                 free_page((unsigned long)up->port.state->xmit.buf);
 546                 up->port.state->xmit.buf = dma_alloc_coherent(NULL,
 547                         UART_XMIT_SIZE,
 548                         (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
 549                         0);
 550                 init_timer(&(up->uart_dma.rx_timer));
 551                 up->uart_dma.rx_timer.function = serial_omap_rxdma_poll;
 552                 up->uart_dma.rx_timer.data = up->port.line;
 553                 /* Currently the buffer size is 4KB. Can increase it */
 554                 up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
 555                         up->uart_dma.rx_buf_size,
 556                         (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0);
 557         }
 558         /*
 559          * Finally, enable interrupts. Note: Modem status interrupts
 560          * are set via set_termios(), which will be occurring imminently
 561          * anyway, so we don't enable them here.
 562          */
 563         up->ier = UART_IER_RLSI | UART_IER_RDI;
 564         serial_out(up, UART_IER, up->ier);
 565
 566         /* Enable module level wake up */
 567         serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
 568
 569         pm_runtime_mark_last_busy(&up->pdev->dev);
 570         pm_runtime_put_autosuspend(&up->pdev->dev);
 571         up->port_activity = jiffies;
 572         return 0;
 573 }
 574
 575 static void serial_omap_shutdown(struct uart_port *port)
 576 {
 577         struct uart_omap_port *up = (struct uart_omap_port *)port;
 578         unsigned long flags = 0;
 579
 580         dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
 581
 582         pm_runtime_get_sync(&up->pdev->dev);
 583         /*
 584          * Disable interrupts from this port
 585          */
 586         up->ier = 0;
 587         serial_out(up, UART_IER, 0);
 588
 589         spin_lock_irqsave(&up->port.lock, flags);
 590         up->port.mctrl &= ~TIOCM_OUT2;
 591         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 592         spin_unlock_irqrestore(&up->port.lock, flags);
 593
 594         /*
 595          * Disable break condition and FIFOs
 596          */
 597         serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 598         serial_omap_clear_fifos(up);
 599
 600         /*
 601          * Read data port to reset things, and then free the irq
 602          */
 603         if (serial_in(up, UART_LSR) & UART_LSR_DR)
 604                 (void) serial_in(up, UART_RX);
 605         if (up->use_dma) {
 606                 dma_free_coherent(up->port.dev,
 607                         UART_XMIT_SIZE, up->port.state->xmit.buf,
 608                         up->uart_dma.tx_buf_dma_phys);
 609                 up->port.state->xmit.buf = NULL;
 610                 serial_omap_stop_rx(port);
 611                 dma_free_coherent(up->port.dev,
 612                         up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
 613                         up->uart_dma.rx_buf_dma_phys);
 614                 up->uart_dma.rx_buf = NULL;
 615         }
 616
 617         pm_runtime_put(&up->pdev->dev);
 618         free_irq(up->port.irq, up);
 619 }
 620
 621 static inline void
 622 serial_omap_configure_xonxoff
 623                 (struct uart_omap_port *up, struct ktermios *termios)
 624 {
 625         up->lcr = serial_in(up, UART_LCR);
 626         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 627         up->efr = serial_in(up, UART_EFR);
 628         serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
 629
 630         serial_out(up, UART_XON1, termios->c_cc[VSTART]);
 631         serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
 632
 633         /* clear SW control mode bits */
 634         up->efr &= OMAP_UART_SW_CLR;
 635
 636         /*
 637          * IXON Flag:
 638          * Enable XON/XOFF flow control on output.
 639          * Transmit XON1, XOFF1
 640          */
 641         if (termios->c_iflag & IXON)
 642                 up->efr |= OMAP_UART_SW_TX;
 643
 644         /*
 645          * IXOFF Flag:
 646          * Enable XON/XOFF flow control on input.
 647          * Receiver compares XON1, XOFF1.
 648          */
 649         if (termios->c_iflag & IXOFF)
 650                 up->efr |= OMAP_UART_SW_RX;
 651
 652         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 653         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 654
 655         up->mcr = serial_in(up, UART_MCR);
 656
 657         /*
 658          * IXANY Flag:
 659          * Enable any character to restart output.
 660          * Operation resumes after receiving any
 661          * character after recognition of the XOFF character
 662          */
 663         if (termios->c_iflag & IXANY)
 664                 up->mcr |= UART_MCR_XONANY;
 665
 666         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 667         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 668         serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
 669         /* Enable special char function UARTi.EFR_REG[5] and
 670          * load the new software flow control mode IXON or IXOFF
 671          * and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
 672          */
 673         serial_out(up, UART_EFR, up->efr | UART_EFR_SCD);
 674         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 675
 676         serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
 677         serial_out(up, UART_LCR, up->lcr);
 678 }
 679
 680 static void serial_omap_uart_qos_work(struct work_struct *work)
 681 {
 682         struct uart_omap_port *up = container_of(work, struct uart_omap_port,
 683                                                 qos_work);
 684
 685         pm_qos_update_request(&up->pm_qos_request, up->latency);
 686 }
 687
 688 static void
 689 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 690                         struct ktermios *old)
 691 {
 692         struct uart_omap_port *up = (struct uart_omap_port *)port;
 693         unsigned char cval = 0;
 694         unsigned char efr = 0;
 695         unsigned long flags = 0;
 696         unsigned int baud, quot;
 697
 698         switch (termios->c_cflag & CSIZE) {
 699         case CS5:
 700                 cval = UART_LCR_WLEN5;
 701                 break;
 702         case CS6:
 703                 cval = UART_LCR_WLEN6;
 704                 break;
 705         case CS7:
 706                 cval = UART_LCR_WLEN7;
 707                 break;
 708         default:
 709         case CS8:
 710                 cval = UART_LCR_WLEN8;
 711                 break;
 712         }
 713
 714         if (termios->c_cflag & CSTOPB)
 715                 cval |= UART_LCR_STOP;
 716         if (termios->c_cflag & PARENB)
 717                 cval |= UART_LCR_PARITY;
 718         if (!(termios->c_cflag & PARODD))
 719                 cval |= UART_LCR_EPAR;
 720
 721         /*
 722          * Ask the core to calculate the divisor for us.
 723          */
 724
 725         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
 726         quot = serial_omap_get_divisor(port, baud);
 727
 728         /* calculate wakeup latency constraint */
 729         up->calc_latency = (1000000 * up->port.fifosize) /
 730                                 (1000 * baud / 8);
 731         up->latency = up->calc_latency;
 732         schedule_work(&up->qos_work);
 733
 734         up->dll = quot & 0xff;
 735         up->dlh = quot >> 8;
 736         up->mdr1 = UART_OMAP_MDR1_DISABLE;
 737
 738         up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
 739                         UART_FCR_ENABLE_FIFO;
 740         if (up->use_dma)
 741                 up->fcr |= UART_FCR_DMA_SELECT;
 742
 743         /*
 744          * Ok, we're now changing the port state. Do it with
 745          * interrupts disabled.
 746          */
 747         pm_runtime_get_sync(&up->pdev->dev);
 748         spin_lock_irqsave(&up->port.lock, flags);
 749
 750         /*
 751          * Update the per-port timeout.
 752          */
 753         uart_update_timeout(port, termios->c_cflag, baud);
 754
 755         up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 756         if (termios->c_iflag & INPCK)
 757                 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 758         if (termios->c_iflag & (BRKINT | PARMRK))
 759                 up->port.read_status_mask |= UART_LSR_BI;
 760
 761         /*
 762          * Characters to ignore
 763          */
 764         up->port.ignore_status_mask = 0;
 765         if (termios->c_iflag & IGNPAR)
 766                 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 767         if (termios->c_iflag & IGNBRK) {
 768                 up->port.ignore_status_mask |= UART_LSR_BI;
 769                 /*
 770                  * If we're ignoring parity and break indicators,
 771                  * ignore overruns too (for real raw support).
 772                  */
 773                 if (termios->c_iflag & IGNPAR)
 774                         up->port.ignore_status_mask |= UART_LSR_OE;
 775         }
 776
 777         /*
 778          * ignore all characters if CREAD is not set
 779          */
 780         if ((termios->c_cflag & CREAD) == 0)
 781                 up->port.ignore_status_mask |= UART_LSR_DR;
 782
 783         /*
 784          * Modem status interrupts
 785          */
 786         up->ier &= ~UART_IER_MSI;
 787         if (UART_ENABLE_MS(&up->port, termios->c_cflag))
 788                 up->ier |= UART_IER_MSI;
 789         serial_out(up, UART_IER, up->ier);
 790         serial_out(up, UART_LCR, cval);         /* reset DLAB */
 791         up->lcr = cval;
 792         up->scr = OMAP_UART_SCR_TX_EMPTY;
 793
 794         /* FIFOs and DMA Settings */
 795
 796         /* FCR can be changed only when the
 797          * baud clock is not running
 798          * DLL_REG and DLH_REG set to 0.
 799          */
 800         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 801         serial_out(up, UART_DLL, 0);
 802         serial_out(up, UART_DLM, 0);
 803         serial_out(up, UART_LCR, 0);
 804
 805         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 806
 807         up->efr = serial_in(up, UART_EFR);
 808         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 809
 810         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 811         up->mcr = serial_in(up, UART_MCR);
 812         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 813         /* FIFO ENABLE, DMA MODE */
 814         serial_out(up, UART_FCR, up->fcr);
 815         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 816
 817         if (up->use_dma) {
 818                 serial_out(up, UART_TI752_TLR, 0);
 819                 up->scr |= (UART_FCR_TRIGGER_4 | UART_FCR_TRIGGER_8);
 820         }
 821
 822         serial_out(up, UART_OMAP_SCR, up->scr);
 823
 824         serial_out(up, UART_EFR, up->efr);
 825         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 826         serial_out(up, UART_MCR, up->mcr);
 827
 828         /* Protocol, Baud Rate, and Interrupt Settings */
 829
 830         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
 831                 serial_omap_mdr1_errataset(up, up->mdr1);
 832         else
 833                 serial_out(up, UART_OMAP_MDR1, up->mdr1);
 834
 835         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 836
 837         up->efr = serial_in(up, UART_EFR);
 838         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 839
 840         serial_out(up, UART_LCR, 0);
 841         serial_out(up, UART_IER, 0);
 842         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 843
 844         serial_out(up, UART_DLL, up->dll);      /* LS of divisor */
 845         serial_out(up, UART_DLM, up->dlh);      /* MS of divisor */
 846
 847         serial_out(up, UART_LCR, 0);
 848         serial_out(up, UART_IER, up->ier);
 849         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 850
 851         serial_out(up, UART_EFR, up->efr);
 852         serial_out(up, UART_LCR, cval);
 853
 854         if (baud > 230400 && baud != 3000000)
 855                 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
 856         else
 857                 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
 858
 859         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
 860                 serial_omap_mdr1_errataset(up, up->mdr1);
 861         else
 862                 serial_out(up, UART_OMAP_MDR1, up->mdr1);
 863
 864         /* Hardware Flow Control Configuration */
 865
 866         if (termios->c_cflag & CRTSCTS) {
 867                 efr |= (UART_EFR_CTS | UART_EFR_RTS);
 868                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 869
 870                 up->mcr = serial_in(up, UART_MCR);
 871                 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 872
 873                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 874                 up->efr = serial_in(up, UART_EFR);
 875                 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 876
 877                 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
 878                 serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
 879                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 880                 serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
 881                 serial_out(up, UART_LCR, cval);
 882         }
 883
 884         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 885         /* Software Flow Control Configuration */
 886         serial_omap_configure_xonxoff(up, termios);
 887
 888         spin_unlock_irqrestore(&up->port.lock, flags);
 889         pm_runtime_put(&up->pdev->dev);
 890         dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
 891 }
 892
 893 static void
 894 serial_omap_pm(struct uart_port *port, unsigned int state,
 895                unsigned int oldstate)
 896 {
 897         struct uart_omap_port *up = (struct uart_omap_port *)port;
 898         unsigned char efr;
 899
 900         dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
 901
 902         pm_runtime_get_sync(&up->pdev->dev);
 903         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 904         efr = serial_in(up, UART_EFR);
 905         serial_out(up, UART_EFR, efr | UART_EFR_ECB);
 906         serial_out(up, UART_LCR, 0);
 907
 908         serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
 909         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 910         serial_out(up, UART_EFR, efr);
 911         serial_out(up, UART_LCR, 0);
 912
 913         if (!device_may_wakeup(&up->pdev->dev)) {
 914                 if (!state)
 915                         pm_runtime_forbid(&up->pdev->dev);
 916                 else
 917                         pm_runtime_allow(&up->pdev->dev);
 918         }
 919
 920         pm_runtime_put(&up->pdev->dev);
 921 }
 922
 923 static void serial_omap_release_port(struct uart_port *port)
 924 {
 925         dev_dbg(port->dev, "serial_omap_release_port+\n");
 926 }
 927
 928 static int serial_omap_request_port(struct uart_port *port)
 929 {
 930         dev_dbg(port->dev, "serial_omap_request_port+\n");
 931         return 0;
 932 }
 933
 934 static void serial_omap_config_port(struct uart_port *port, int flags)
 935 {
 936         struct uart_omap_port *up = (struct uart_omap_port *)port;
 937
 938         dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
 939                                                         up->port.line);
 940         up->port.type = PORT_OMAP;
 941 }
 942
 943 static int
 944 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
 945 {
 946         /* we don't want the core code to modify any port params */
 947         dev_dbg(port->dev, "serial_omap_verify_port+\n");
 948         return -EINVAL;
 949 }
 950
 951 static const char *
 952 serial_omap_type(struct uart_port *port)
 953 {
 954         struct uart_omap_port *up = (struct uart_omap_port *)port;
 955
 956         dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
 957         return up->name;
 958 }
 959
 960 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
 961
 962 static inline void wait_for_xmitr(struct uart_omap_port *up)
 963 {
 964         unsigned int status, tmout = 10000;
 965
 966         /* Wait up to 10ms for the character(s) to be sent. */
 967         do {
 968                 status = serial_in(up, UART_LSR);
 969
 970                 if (status & UART_LSR_BI)
 971                         up->lsr_break_flag = UART_LSR_BI;
 972
 973                 if (--tmout == 0)
 974                         break;
 975                 udelay(1);
 976         } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
 977
 978         /* Wait up to 1s for flow control if necessary */
 979         if (up->port.flags & UPF_CONS_FLOW) {
 980                 tmout = 1000000;
 981                 for (tmout = 1000000; tmout; tmout--) {
 982                         unsigned int msr = serial_in(up, UART_MSR);
 983
 984                         up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
 985                         if (msr & UART_MSR_CTS)
 986                                 break;
 987
 988                         udelay(1);
 989                 }
 990         }
 991 }
 992
 993 #ifdef CONFIG_CONSOLE_POLL
 994
 995 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
 996 {
 997         struct uart_omap_port *up = (struct uart_omap_port *)port;
 998
 999         pm_runtime_get_sync(&up->pdev->dev);
1000         wait_for_xmitr(up);
1001         serial_out(up, UART_TX, ch);
1002         pm_runtime_put(&up->pdev->dev);
1003 }
1004
1005 static int serial_omap_poll_get_char(struct uart_port *port)
1006 {
1007         struct uart_omap_port *up = (struct uart_omap_port *)port;
1008         unsigned int status;
1009
1010         pm_runtime_get_sync(&up->pdev->dev);
1011         status = serial_in(up, UART_LSR);
1012         if (!(status & UART_LSR_DR))
1013                 return NO_POLL_CHAR;
1014
1015         status = serial_in(up, UART_RX);
1016         pm_runtime_put(&up->pdev->dev);
1017         return status;
1018 }
1019
1020 #endif /* CONFIG_CONSOLE_POLL */
1021
1022 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1023
1024 static struct uart_omap_port *serial_omap_console_ports[4];
1025
1026 static struct uart_driver serial_omap_reg;
1027
1028 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1029 {
1030         struct uart_omap_port *up = (struct uart_omap_port *)port;
1031
1032         wait_for_xmitr(up);
1033         serial_out(up, UART_TX, ch);
1034 }
1035
1036 static void
1037 serial_omap_console_write(struct console *co, const char *s,
1038                 unsigned int count)
1039 {
1040         struct uart_omap_port *up = serial_omap_console_ports[co->index];
1041         unsigned long flags;
1042         unsigned int ier;
1043         int locked = 1;
1044
1045         pm_runtime_get_sync(&up->pdev->dev);
1046
1047         local_irq_save(flags);
1048         if (up->port.sysrq)
1049                 locked = 0;
1050         else if (oops_in_progress)
1051                 locked = spin_trylock(&up->port.lock);
1052         else
1053                 spin_lock(&up->port.lock);
1054
1055         /*
1056          * First save the IER then disable the interrupts
1057          */
1058         ier = serial_in(up, UART_IER);
1059         serial_out(up, UART_IER, 0);
1060
1061         uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1062
1063         /*
1064          * Finally, wait for transmitter to become empty
1065          * and restore the IER
1066          */
1067         wait_for_xmitr(up);
1068         serial_out(up, UART_IER, ier);
1069         /*
1070          * The receive handling will happen properly because the
1071          * receive ready bit will still be set; it is not cleared
1072          * on read.  However, modem control will not, we must
1073          * call it if we have saved something in the saved flags
1074          * while processing with interrupts off.
1075          */
1076         if (up->msr_saved_flags)
1077                 check_modem_status(up);
1078
1079         pm_runtime_mark_last_busy(&up->pdev->dev);
1080         pm_runtime_put_autosuspend(&up->pdev->dev);
1081         if (locked)
1082                 spin_unlock(&up->port.lock);
1083         local_irq_restore(flags);
1084 }
1085
1086 static int __init
1087 serial_omap_console_setup(struct console *co, char *options)
1088 {
1089         struct uart_omap_port *up;
1090         int baud = 115200;
1091         int bits = 8;
1092         int parity = 'n';
1093         int flow = 'n';
1094
1095         if (serial_omap_console_ports[co->index] == NULL)
1096                 return -ENODEV;
1097         up = serial_omap_console_ports[co->index];
1098
1099         if (options)
1100                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1101
1102         return uart_set_options(&up->port, co, baud, parity, bits, flow);
1103 }
1104
1105 static struct console serial_omap_console = {
1106         .name           = OMAP_SERIAL_NAME,
1107         .write          = serial_omap_console_write,
1108         .device         = uart_console_device,
1109         .setup          = serial_omap_console_setup,
1110         .flags          = CON_PRINTBUFFER,
1111         .index          = -1,
1112         .data           = &serial_omap_reg,
1113 };
1114
1115 static void serial_omap_add_console_port(struct uart_omap_port *up)
1116 {
1117         serial_omap_console_ports[up->port.line] = up;
1118 }
1119
1120 #define OMAP_CONSOLE    (&serial_omap_console)
1121
1122 #else
1123
1124 #define OMAP_CONSOLE    NULL
1125
1126 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1127 {}
1128
1129 #endif
1130
1131 static struct uart_ops serial_omap_pops = {
1132         .tx_empty       = serial_omap_tx_empty,
1133         .set_mctrl      = serial_omap_set_mctrl,
1134         .get_mctrl      = serial_omap_get_mctrl,
1135         .stop_tx        = serial_omap_stop_tx,
1136         .start_tx       = serial_omap_start_tx,
1137         .stop_rx        = serial_omap_stop_rx,
1138         .enable_ms      = serial_omap_enable_ms,
1139         .break_ctl      = serial_omap_break_ctl,
1140         .startup        = serial_omap_startup,
1141         .shutdown       = serial_omap_shutdown,
1142         .set_termios    = serial_omap_set_termios,
1143         .pm             = serial_omap_pm,
1144         .type           = serial_omap_type,
1145         .release_port   = serial_omap_release_port,
1146         .request_port   = serial_omap_request_port,
1147         .config_port    = serial_omap_config_port,
1148         .verify_port    = serial_omap_verify_port,
1149 #ifdef CONFIG_CONSOLE_POLL
1150         .poll_put_char  = serial_omap_poll_put_char,
1151         .poll_get_char  = serial_omap_poll_get_char,
1152 #endif
1153 };
1154
1155 static struct uart_driver serial_omap_reg = {
1156         .owner          = THIS_MODULE,
1157         .driver_name    = "OMAP-SERIAL",
1158         .dev_name       = OMAP_SERIAL_NAME,
1159         .nr             = OMAP_MAX_HSUART_PORTS,
1160         .cons           = OMAP_CONSOLE,
1161 };
1162
1163 #ifdef CONFIG_SUSPEND
1164 static int serial_omap_suspend(struct device *dev)
1165 {
1166         struct uart_omap_port *up = dev_get_drvdata(dev);
1167
1168         if (up) {
1169                 uart_suspend_port(&serial_omap_reg, &up->port);
1170                 flush_work_sync(&up->qos_work);
1171         }
1172
1173         return 0;
1174 }
1175
1176 static int serial_omap_resume(struct device *dev)
1177 {
1178         struct uart_omap_port *up = dev_get_drvdata(dev);
1179
1180         if (up)
1181                 uart_resume_port(&serial_omap_reg, &up->port);
1182         return 0;
1183 }
1184 #endif
1185
1186 static void serial_omap_rxdma_poll(unsigned long uart_no)
1187 {
1188         struct uart_omap_port *up = ui[uart_no];
1189         unsigned int curr_dma_pos, curr_transmitted_size;
1190         int ret = 0;
1191
1192         curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
1193         if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
1194                              (curr_dma_pos == 0)) {
1195                 if (jiffies_to_msecs(jiffies - up->port_activity) <
1196                                                 up->uart_dma.rx_timeout) {
1197                         mod_timer(&up->uart_dma.rx_timer, jiffies +
1198                                 usecs_to_jiffies(up->uart_dma.rx_poll_rate));
1199                 } else {
1200                         serial_omap_stop_rxdma(up);
1201                         up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1202                         serial_out(up, UART_IER, up->ier);
1203                 }
1204                 return;
1205         }
1206
1207         curr_transmitted_size = curr_dma_pos -
1208                                         up->uart_dma.prev_rx_dma_pos;
1209         up->port.icount.rx += curr_transmitted_size;
1210         tty_insert_flip_string(up->port.state->port.tty,
1211                         up->uart_dma.rx_buf +
1212                         (up->uart_dma.prev_rx_dma_pos -
1213                         up->uart_dma.rx_buf_dma_phys),
1214                         curr_transmitted_size);
1215         tty_flip_buffer_push(up->port.state->port.tty);
1216         up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
1217         if (up->uart_dma.rx_buf_size +
1218                         up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
1219                 ret = serial_omap_start_rxdma(up);
1220                 if (ret < 0) {
1221                         serial_omap_stop_rxdma(up);
1222                         up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1223                         serial_out(up, UART_IER, up->ier);
1224                 }
1225         } else  {
1226                 mod_timer(&up->uart_dma.rx_timer, jiffies +
1227                         usecs_to_jiffies(up->uart_dma.rx_poll_rate));
1228         }
1229         up->port_activity = jiffies;
1230 }
1231
1232 static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
1233 {
1234         return;
1235 }
1236
1237 static int serial_omap_start_rxdma(struct uart_omap_port *up)
1238 {
1239         int ret = 0;
1240
1241         if (up->uart_dma.rx_dma_channel == -1) {
1242                 pm_runtime_get_sync(&up->pdev->dev);
1243                 ret = omap_request_dma(up->uart_dma.uart_dma_rx,
1244                                 "UART Rx DMA",
1245                                 (void *)uart_rx_dma_callback, up,
1246                                 &(up->uart_dma.rx_dma_channel));
1247                 if (ret < 0)
1248                         return ret;
1249
1250                 omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
1251                                 OMAP_DMA_AMODE_CONSTANT,
1252                                 up->uart_dma.uart_base, 0, 0);
1253                 omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
1254                                 OMAP_DMA_AMODE_POST_INC,
1255                                 up->uart_dma.rx_buf_dma_phys, 0, 0);
1256                 omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
1257                                 OMAP_DMA_DATA_TYPE_S8,
1258                                 up->uart_dma.rx_buf_size, 1,
1259                                 OMAP_DMA_SYNC_ELEMENT,
1260                                 up->uart_dma.uart_dma_rx, 0);
1261         }
1262         up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
1263         /* FIXME: Cache maintenance needed here? */
1264         omap_start_dma(up->uart_dma.rx_dma_channel);
1265         mod_timer(&up->uart_dma.rx_timer, jiffies +
1266                                 usecs_to_jiffies(up->uart_dma.rx_poll_rate));
1267         up->uart_dma.rx_dma_used = true;
1268         return ret;
1269 }
1270
1271 static void serial_omap_continue_tx(struct uart_omap_port *up)
1272 {
1273         struct circ_buf *xmit = &up->port.state->xmit;
1274         unsigned int start = up->uart_dma.tx_buf_dma_phys
1275                         + (xmit->tail & (UART_XMIT_SIZE - 1));
1276
1277         if (uart_circ_empty(xmit))
1278                 return;
1279
1280         up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
1281         /*
1282          * It is a circular buffer. See if the buffer has wounded back.
1283          * If yes it will have to be transferred in two separate dma
1284          * transfers
1285          */
1286         if (start + up->uart_dma.tx_buf_size >=
1287                         up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
1288                 up->uart_dma.tx_buf_size =
1289                         (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
1290         omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
1291                                 OMAP_DMA_AMODE_CONSTANT,
1292                                 up->uart_dma.uart_base, 0, 0);
1293         omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
1294                                 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
1295         omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
1296                                 OMAP_DMA_DATA_TYPE_S8,
1297                                 up->uart_dma.tx_buf_size, 1,
1298                                 OMAP_DMA_SYNC_ELEMENT,
1299                                 up->uart_dma.uart_dma_tx, 0);
1300         /* FIXME: Cache maintenance needed here? */
1301         omap_start_dma(up->uart_dma.tx_dma_channel);
1302 }
1303
1304 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
1305 {
1306         struct uart_omap_port *up = (struct uart_omap_port *)data;
1307         struct circ_buf *xmit = &up->port.state->xmit;
1308
1309         xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
1310                         (UART_XMIT_SIZE - 1);
1311         up->port.icount.tx += up->uart_dma.tx_buf_size;
1312
1313         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1314                 uart_write_wakeup(&up->port);
1315
1316         if (uart_circ_empty(xmit)) {
1317                 spin_lock(&(up->uart_dma.tx_lock));
1318                 serial_omap_stop_tx(&up->port);
1319                 up->uart_dma.tx_dma_used = false;
1320                 spin_unlock(&(up->uart_dma.tx_lock));
1321         } else {
1322                 omap_stop_dma(up->uart_dma.tx_dma_channel);
1323                 serial_omap_continue_tx(up);
1324         }
1325         up->port_activity = jiffies;
1326         return;
1327 }
1328
1329 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1330 {
1331         struct omap_uart_port_info *omap_up_info;
1332
1333         omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1334         if (!omap_up_info)
1335                 return NULL; /* out of memory */
1336
1337         of_property_read_u32(dev->of_node, "clock-frequency",
1338                                          &omap_up_info->uartclk);
1339         return omap_up_info;
1340 }
1341
1342 static int serial_omap_probe(struct platform_device *pdev)
1343 {
1344         struct uart_omap_port   *up;
1345         struct resource         *mem, *irq, *dma_tx, *dma_rx;
1346         struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1347         int ret = -ENOSPC;
1348
1349         if (pdev->dev.of_node)
1350                 omap_up_info = of_get_uart_port_info(&pdev->dev);
1351
1352         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1353         if (!mem) {
1354                 dev_err(&pdev->dev, "no mem resource?\n");
1355                 return -ENODEV;
1356         }
1357
1358         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1359         if (!irq) {
1360                 dev_err(&pdev->dev, "no irq resource?\n");
1361                 return -ENODEV;
1362         }
1363
1364         if (!request_mem_region(mem->start, resource_size(mem),
1365                                 pdev->dev.driver->name)) {
1366                 dev_err(&pdev->dev, "memory region already claimed\n");
1367                 return -EBUSY;
1368         }
1369
1370         dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1371         if (!dma_rx) {
1372                 ret = -EINVAL;
1373                 goto err;
1374         }
1375
1376         dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1377         if (!dma_tx) {
1378                 ret = -EINVAL;
1379                 goto err;
1380         }
1381
1382         up = kzalloc(sizeof(*up), GFP_KERNEL);
1383         if (up == NULL) {
1384                 ret = -ENOMEM;
1385                 goto do_release_region;
1386         }
1387         up->pdev = pdev;
1388         up->port.dev = &pdev->dev;
1389         up->port.type = PORT_OMAP;
1390         up->port.iotype = UPIO_MEM;
1391         up->port.irq = irq->start;
1392
1393         up->port.regshift = 2;
1394         up->port.fifosize = 64;
1395         up->port.ops = &serial_omap_pops;
1396
1397         if (pdev->dev.of_node)
1398                 up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
1399         else
1400                 up->port.line = pdev->id;
1401
1402         if (up->port.line < 0) {
1403                 dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1404                                                                 up->port.line);
1405                 ret = -ENODEV;
1406                 goto err;
1407         }
1408
1409         sprintf(up->name, "OMAP UART%d", up->port.line);
1410         up->port.mapbase = mem->start;
1411         up->port.membase = ioremap(mem->start, resource_size(mem));
1412         if (!up->port.membase) {
1413                 dev_err(&pdev->dev, "can't ioremap UART\n");
1414                 ret = -ENOMEM;
1415                 goto err;
1416         }
1417
1418         up->port.flags = omap_up_info->flags;
1419         up->port.uartclk = omap_up_info->uartclk;
1420         if (!up->port.uartclk) {
1421                 up->port.uartclk = DEFAULT_CLK_SPEED;
1422                 dev_warn(&pdev->dev, "No clock speed specified: using default:"
1423                                                 "%d\n", DEFAULT_CLK_SPEED);
1424         }
1425         up->uart_dma.uart_base = mem->start;
1426         up->errata = omap_up_info->errata;
1427
1428         if (omap_up_info->dma_enabled) {
1429                 up->uart_dma.uart_dma_tx = dma_tx->start;
1430                 up->uart_dma.uart_dma_rx = dma_rx->start;
1431                 up->use_dma = 1;
1432                 up->uart_dma.rx_buf_size = omap_up_info->dma_rx_buf_size;
1433                 up->uart_dma.rx_timeout = omap_up_info->dma_rx_timeout;
1434                 up->uart_dma.rx_poll_rate = omap_up_info->dma_rx_poll_rate;
1435                 spin_lock_init(&(up->uart_dma.tx_lock));
1436                 spin_lock_init(&(up->uart_dma.rx_lock));
1437                 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
1438                 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
1439         }
1440
1441         up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1442         up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1443         pm_qos_add_request(&up->pm_qos_request,
1444                 PM_QOS_CPU_DMA_LATENCY, up->latency);
1445         serial_omap_uart_wq = create_singlethread_workqueue(up->name);
1446         INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1447
1448         pm_runtime_use_autosuspend(&pdev->dev);
1449         pm_runtime_set_autosuspend_delay(&pdev->dev,
1450                         omap_up_info->autosuspend_timeout);
1451
1452         pm_runtime_irq_safe(&pdev->dev);
1453         pm_runtime_enable(&pdev->dev);
1454         pm_runtime_get_sync(&pdev->dev);
1455
1456         ui[up->port.line] = up;
1457         serial_omap_add_console_port(up);
1458
1459         ret = uart_add_one_port(&serial_omap_reg, &up->port);
1460         if (ret != 0)
1461                 goto do_release_region;
1462
1463         pm_runtime_put(&pdev->dev);
1464         platform_set_drvdata(pdev, up);
1465         return 0;
1466 err:
1467         dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1468                                 pdev->id, __func__, ret);
1469 do_release_region:
1470         release_mem_region(mem->start, resource_size(mem));
1471         return ret;
1472 }
1473
1474 static int serial_omap_remove(struct platform_device *dev)
1475 {
1476         struct uart_omap_port *up = platform_get_drvdata(dev);
1477
1478         if (up) {
1479                 pm_runtime_disable(&up->pdev->dev);
1480                 uart_remove_one_port(&serial_omap_reg, &up->port);
1481                 pm_qos_remove_request(&up->pm_qos_request);
1482
1483                 kfree(up);
1484         }
1485
1486         platform_set_drvdata(dev, NULL);
1487         return 0;
1488 }
1489
1490 /*
1491  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1492  * The access to uart register after MDR1 Access
1493  * causes UART to corrupt data.
1494  *
1495  * Need a delay =
1496  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1497  * give 10 times as much
1498  */
1499 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1500 {
1501         u8 timeout = 255;
1502
1503         serial_out(up, UART_OMAP_MDR1, mdr1);
1504         udelay(2);
1505         serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1506                         UART_FCR_CLEAR_RCVR);
1507         /*
1508          * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1509          * TX_FIFO_E bit is 1.
1510          */
1511         while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1512                                 (UART_LSR_THRE | UART_LSR_DR))) {
1513                 timeout--;
1514                 if (!timeout) {
1515                         /* Should *never* happen. we warn and carry on */
1516                         dev_crit(&up->pdev->dev, "Errata i202: timedout %x\n",
1517                                                 serial_in(up, UART_LSR));
1518                         break;
1519                 }
1520                 udelay(1);
1521         }
1522 }
1523
1524 static void serial_omap_restore_context(struct uart_omap_port *up)
1525 {
1526         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1527                 serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1528         else
1529                 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1530
1531         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1532         serial_out(up, UART_EFR, UART_EFR_ECB);
1533         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1534         serial_out(up, UART_IER, 0x0);
1535         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1536         serial_out(up, UART_DLL, up->dll);
1537         serial_out(up, UART_DLM, up->dlh);
1538         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1539         serial_out(up, UART_IER, up->ier);
1540         serial_out(up, UART_FCR, up->fcr);
1541         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1542         serial_out(up, UART_MCR, up->mcr);
1543         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1544         serial_out(up, UART_OMAP_SCR, up->scr);
1545         serial_out(up, UART_EFR, up->efr);
1546         serial_out(up, UART_LCR, up->lcr);
1547         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1548                 serial_omap_mdr1_errataset(up, up->mdr1);
1549         else
1550                 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1551 }
1552
1553 #ifdef CONFIG_PM_RUNTIME
1554 static int serial_omap_runtime_suspend(struct device *dev)
1555 {
1556         struct uart_omap_port *up = dev_get_drvdata(dev);
1557         struct omap_uart_port_info *pdata = dev->platform_data;
1558
1559         if (!up)
1560                 return -EINVAL;
1561
1562         if (!pdata || !pdata->enable_wakeup)
1563                 return 0;
1564
1565         if (pdata->get_context_loss_count)
1566                 up->context_loss_cnt = pdata->get_context_loss_count(dev);
1567
1568         if (device_may_wakeup(dev)) {
1569                 if (!up->wakeups_enabled) {
1570                         pdata->enable_wakeup(up->pdev, true);
1571                         up->wakeups_enabled = true;
1572                 }
1573         } else {
1574                 if (up->wakeups_enabled) {
1575                         pdata->enable_wakeup(up->pdev, false);
1576                         up->wakeups_enabled = false;
1577                 }
1578         }
1579
1580         /* Errata i291 */
1581         if (up->use_dma && pdata->set_forceidle &&
1582                         (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE))
1583                 pdata->set_forceidle(up->pdev);
1584
1585         up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1586         schedule_work(&up->qos_work);
1587
1588         return 0;
1589 }
1590
1591 static int serial_omap_runtime_resume(struct device *dev)
1592 {
1593         struct uart_omap_port *up = dev_get_drvdata(dev);
1594         struct omap_uart_port_info *pdata = dev->platform_data;
1595
1596         if (up) {
1597                 if (pdata->get_context_loss_count) {
1598                         u32 loss_cnt = pdata->get_context_loss_count(dev);
1599
1600                         if (up->context_loss_cnt != loss_cnt)
1601                                 serial_omap_restore_context(up);
1602                 }
1603
1604                 /* Errata i291 */
1605                 if (up->use_dma && pdata->set_noidle &&
1606                                 (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE))
1607                         pdata->set_noidle(up->pdev);
1608
1609                 up->latency = up->calc_latency;
1610                 schedule_work(&up->qos_work);
1611         }
1612
1613         return 0;
1614 }
1615 #endif
1616
1617 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1618         SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1619         SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1620                                 serial_omap_runtime_resume, NULL)
1621 };
1622
1623 #if defined(CONFIG_OF)
1624 static const struct of_device_id omap_serial_of_match[] = {
1625         { .compatible = "ti,omap2-uart" },
1626         { .compatible = "ti,omap3-uart" },
1627         { .compatible = "ti,omap4-uart" },
1628         {},
1629 };
1630 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1631 #endif
1632
1633 static struct platform_driver serial_omap_driver = {
1634         .probe          = serial_omap_probe,
1635         .remove         = serial_omap_remove,
1636         .driver         = {
1637                 .name   = DRIVER_NAME,
1638                 .pm     = &serial_omap_dev_pm_ops,
1639                 .of_match_table = of_match_ptr(omap_serial_of_match),
1640         },
1641 };
1642
1643 static int __init serial_omap_init(void)
1644 {
1645         int ret;
1646
1647         ret = uart_register_driver(&serial_omap_reg);
1648         if (ret != 0)
1649                 return ret;
1650         ret = platform_driver_register(&serial_omap_driver);
1651         if (ret != 0)
1652                 uart_unregister_driver(&serial_omap_reg);
1653         return ret;
1654 }
1655
1656 static void __exit serial_omap_exit(void)
1657 {
1658         platform_driver_unregister(&serial_omap_driver);
1659         uart_unregister_driver(&serial_omap_reg);
1660 }
1661
1662 module_init(serial_omap_init);
1663 module_exit(serial_omap_exit);
1664
1665 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1666 MODULE_LICENSE("GPL");
1667 MODULE_AUTHOR("Texas Instruments Inc");