drivers/serial/msm_serial.c

   1 /*
   2  * drivers/serial/msm_serial.c - driver for msm7k serial device and console
   3  *
   4  * Copyright (C) 2007 Google, Inc.
   5  * Author: Robert Love <rlove@google.com>
   6  *
   7  * This software is licensed under the terms of the GNU General Public
   8  * License version 2, as published by the Free Software Foundation, and
   9  * may be copied, distributed, and modified under those terms.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #if defined(CONFIG_SERIAL_MSM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  18 # define SUPPORT_SYSRQ
  19 #endif
  20
  21 #include <linux/hrtimer.h>
  22 #include <linux/module.h>
  23 #include <linux/io.h>
  24 #include <linux/ioport.h>
  25 #include <linux/irq.h>
  26 #include <linux/init.h>
  27 #include <linux/console.h>
  28 #include <linux/tty.h>
  29 #include <linux/tty_flip.h>
  30 #include <linux/serial_core.h>
  31 #include <linux/serial.h>
  32 #include <linux/clk.h>
  33 #include <linux/platform_device.h>
  34
  35 #include "msm_serial.h"
  36
  37 struct msm_port {
  38         struct uart_port        uart;
  39         char                    name[16];
  40         struct clk              *clk;
  41         unsigned int            imr;
  42 };
  43
  44 #define UART_TO_MSM(uart_port)  ((struct msm_port *) uart_port)
  45
  46 static inline void msm_write(struct uart_port *port, unsigned int val,
  47                              unsigned int off)
  48 {
  49         __raw_writel(val, port->membase + off);
  50 }
  51
  52 static inline unsigned int msm_read(struct uart_port *port, unsigned int off)
  53 {
  54         return __raw_readl(port->membase + off);
  55 }
  56
  57 static void msm_stop_tx(struct uart_port *port)
  58 {
  59         struct msm_port *msm_port = UART_TO_MSM(port);
  60
  61         msm_port->imr &= ~UART_IMR_TXLEV;
  62         msm_write(port, msm_port->imr, UART_IMR);
  63 }
  64
  65 static void msm_start_tx(struct uart_port *port)
  66 {
  67         struct msm_port *msm_port = UART_TO_MSM(port);
  68
  69         msm_port->imr |= UART_IMR_TXLEV;
  70         msm_write(port, msm_port->imr, UART_IMR);
  71 }
  72
  73 static void msm_stop_rx(struct uart_port *port)
  74 {
  75         struct msm_port *msm_port = UART_TO_MSM(port);
  76
  77         msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
  78         msm_write(port, msm_port->imr, UART_IMR);
  79 }
  80
  81 static void msm_enable_ms(struct uart_port *port)
  82 {
  83         struct msm_port *msm_port = UART_TO_MSM(port);
  84
  85         msm_port->imr |= UART_IMR_DELTA_CTS;
  86         msm_write(port, msm_port->imr, UART_IMR);
  87 }
  88
  89 static void handle_rx(struct uart_port *port)
  90 {
  91         struct tty_struct *tty = port->info->port.tty;
  92         unsigned int sr;
  93
  94         /*
  95          * Handle overrun. My understanding of the hardware is that overrun
  96          * is not tied to the RX buffer, so we handle the case out of band.
  97          */
  98         if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
  99                 port->icount.overrun++;
 100                 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 101                 msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 102         }
 103
 104         /* and now the main RX loop */
 105         while ((sr = msm_read(port, UART_SR)) & UART_SR_RX_READY) {
 106                 unsigned int c;
 107                 char flag = TTY_NORMAL;
 108
 109                 c = msm_read(port, UART_RF);
 110
 111                 if (sr & UART_SR_RX_BREAK) {
 112                         port->icount.brk++;
 113                         if (uart_handle_break(port))
 114                                 continue;
 115                 } else if (sr & UART_SR_PAR_FRAME_ERR) {
 116                         port->icount.frame++;
 117                 } else {
 118                         port->icount.rx++;
 119                 }
 120
 121                 /* Mask conditions we're ignorning. */
 122                 sr &= port->read_status_mask;
 123
 124                 if (sr & UART_SR_RX_BREAK) {
 125                         flag = TTY_BREAK;
 126                 } else if (sr & UART_SR_PAR_FRAME_ERR) {
 127                         flag = TTY_FRAME;
 128                 }
 129
 130                 if (!uart_handle_sysrq_char(port, c))
 131                         tty_insert_flip_char(tty, c, flag);
 132         }
 133
 134         tty_flip_buffer_push(tty);
 135 }
 136
 137 static void handle_tx(struct uart_port *port)
 138 {
 139         struct circ_buf *xmit = &port->info->xmit;
 140         struct msm_port *msm_port = UART_TO_MSM(port);
 141         int sent_tx;
 142
 143         if (port->x_char) {
 144                 msm_write(port, port->x_char, UART_TF);
 145                 port->icount.tx++;
 146                 port->x_char = 0;
 147         }
 148
 149         while (msm_read(port, UART_SR) & UART_SR_TX_READY) {
 150                 if (uart_circ_empty(xmit)) {
 151                         /* disable tx interrupts */
 152                         msm_port->imr &= ~UART_IMR_TXLEV;
 153                         msm_write(port, msm_port->imr, UART_IMR);
 154                         break;
 155                 }
 156
 157                 msm_write(port, xmit->buf[xmit->tail], UART_TF);
 158
 159                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 160                 port->icount.tx++;
 161                 sent_tx = 1;
 162         }
 163
 164         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 165                 uart_write_wakeup(port);
 166 }
 167
 168 static void handle_delta_cts(struct uart_port *port)
 169 {
 170         msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
 171         port->icount.cts++;
 172         wake_up_interruptible(&port->info->delta_msr_wait);
 173 }
 174
 175 static irqreturn_t msm_irq(int irq, void *dev_id)
 176 {
 177         struct uart_port *port = dev_id;
 178         struct msm_port *msm_port = UART_TO_MSM(port);
 179         unsigned int misr;
 180
 181         spin_lock(&port->lock);
 182         misr = msm_read(port, UART_MISR);
 183         msm_write(port, 0, UART_IMR); /* disable interrupt */
 184
 185         if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE))
 186                 handle_rx(port);
 187         if (misr & UART_IMR_TXLEV)
 188                 handle_tx(port);
 189         if (misr & UART_IMR_DELTA_CTS)
 190                 handle_delta_cts(port);
 191
 192         msm_write(port, msm_port->imr, UART_IMR); /* restore interrupt */
 193         spin_unlock(&port->lock);
 194
 195         return IRQ_HANDLED;
 196 }
 197
 198 static unsigned int msm_tx_empty(struct uart_port *port)
 199 {
 200         return (msm_read(port, UART_SR) & UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
 201 }
 202
 203 static unsigned int msm_get_mctrl(struct uart_port *port)
 204 {
 205         return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
 206 }
 207
 208 static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
 209 {
 210         unsigned int mr;
 211
 212         mr = msm_read(port, UART_MR1);
 213
 214         if (!(mctrl & TIOCM_RTS)) {
 215                 mr &= ~UART_MR1_RX_RDY_CTL;
 216                 msm_write(port, mr, UART_MR1);
 217                 msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
 218         } else {
 219                 mr |= UART_MR1_RX_RDY_CTL;
 220                 msm_write(port, mr, UART_MR1);
 221         }
 222 }
 223
 224 static void msm_break_ctl(struct uart_port *port, int break_ctl)
 225 {
 226         if (break_ctl)
 227                 msm_write(port, UART_CR_CMD_START_BREAK, UART_CR);
 228         else
 229                 msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
 230 }
 231
 232 static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
 233 {
 234         unsigned int baud_code, rxstale, watermark;
 235
 236         switch (baud) {
 237         case 300:
 238                 baud_code = UART_CSR_300;
 239                 rxstale = 1;
 240                 break;
 241         case 600:
 242                 baud_code = UART_CSR_600;
 243                 rxstale = 1;
 244                 break;
 245         case 1200:
 246                 baud_code = UART_CSR_1200;
 247                 rxstale = 1;
 248                 break;
 249         case 2400:
 250                 baud_code = UART_CSR_2400;
 251                 rxstale = 1;
 252                 break;
 253         case 4800:
 254                 baud_code = UART_CSR_4800;
 255                 rxstale = 1;
 256                 break;
 257         case 9600:
 258                 baud_code = UART_CSR_9600;
 259                 rxstale = 2;
 260                 break;
 261         case 14400:
 262                 baud_code = UART_CSR_14400;
 263                 rxstale = 3;
 264                 break;
 265         case 19200:
 266                 baud_code = UART_CSR_19200;
 267                 rxstale = 4;
 268                 break;
 269         case 28800:
 270                 baud_code = UART_CSR_28800;
 271                 rxstale = 6;
 272                 break;
 273         case 38400:
 274                 baud_code = UART_CSR_38400;
 275                 rxstale = 8;
 276                 break;
 277         case 57600:
 278                 baud_code = UART_CSR_57600;
 279                 rxstale = 16;
 280                 break;
 281         case 115200:
 282         default:
 283                 baud_code = UART_CSR_115200;
 284                 baud = 115200;
 285                 rxstale = 31;
 286                 break;
 287         }
 288
 289         msm_write(port, baud_code, UART_CSR);
 290
 291         /* RX stale watermark */
 292         watermark = UART_IPR_STALE_LSB & rxstale;
 293         watermark |= UART_IPR_RXSTALE_LAST;
 294         watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
 295         msm_write(port, watermark, UART_IPR);
 296
 297         /* set RX watermark */
 298         watermark = (port->fifosize * 3) / 4;
 299         msm_write(port, watermark, UART_RFWR);
 300
 301         /* set TX watermark */
 302         msm_write(port, 10, UART_TFWR);
 303
 304         return baud;
 305 }
 306
 307 static void msm_reset(struct uart_port *port)
 308 {
 309         /* reset everything */
 310         msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
 311         msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
 312         msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 313         msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR);
 314         msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
 315         msm_write(port, UART_CR_CMD_SET_RFR, UART_CR);
 316 }
 317
 318 static void msm_init_clock(struct uart_port *port)
 319 {
 320         struct msm_port *msm_port = UART_TO_MSM(port);
 321
 322         clk_enable(msm_port->clk);
 323
 324         msm_write(port, 0xC0, UART_MREG);
 325         msm_write(port, 0xB2, UART_NREG);
 326         msm_write(port, 0x7D, UART_DREG);
 327         msm_write(port, 0x1C, UART_MNDREG);
 328 }
 329
 330 static int msm_startup(struct uart_port *port)
 331 {
 332         struct msm_port *msm_port = UART_TO_MSM(port);
 333         unsigned int data, rfr_level;
 334         int ret;
 335
 336         snprintf(msm_port->name, sizeof(msm_port->name),
 337                  "msm_serial%d", port->line);
 338
 339         ret = request_irq(port->irq, msm_irq, IRQF_TRIGGER_HIGH,
 340                           msm_port->name, port);
 341         if (unlikely(ret))
 342                 return ret;
 343
 344         msm_init_clock(port);
 345
 346         if (likely(port->fifosize > 12))
 347                 rfr_level = port->fifosize - 12;
 348         else
 349                 rfr_level = port->fifosize;
 350
 351         /* set automatic RFR level */
 352         data = msm_read(port, UART_MR1);
 353         data &= ~UART_MR1_AUTO_RFR_LEVEL1;
 354         data &= ~UART_MR1_AUTO_RFR_LEVEL0;
 355         data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
 356         data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
 357         msm_write(port, data, UART_MR1);
 358
 359         /* make sure that RXSTALE count is non-zero */
 360         data = msm_read(port, UART_IPR);
 361         if (unlikely(!data)) {
 362                 data |= UART_IPR_RXSTALE_LAST;
 363                 data |= UART_IPR_STALE_LSB;
 364                 msm_write(port, data, UART_IPR);
 365         }
 366
 367         msm_reset(port);
 368
 369         msm_write(port, 0x05, UART_CR); /* enable TX & RX */
 370
 371         /* turn on RX and CTS interrupts */
 372         msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE |
 373                         UART_IMR_CURRENT_CTS;
 374         msm_write(port, msm_port->imr, UART_IMR);
 375
 376         return 0;
 377 }
 378
 379 static void msm_shutdown(struct uart_port *port)
 380 {
 381         struct msm_port *msm_port = UART_TO_MSM(port);
 382
 383         msm_port->imr = 0;
 384         msm_write(port, 0, UART_IMR); /* disable interrupts */
 385
 386         clk_disable(msm_port->clk);
 387
 388         free_irq(port->irq, port);
 389 }
 390
 391 static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
 392                             struct ktermios *old)
 393 {
 394         unsigned long flags;
 395         unsigned int baud, mr;
 396
 397         spin_lock_irqsave(&port->lock, flags);
 398
 399         /* calculate and set baud rate */
 400         baud = uart_get_baud_rate(port, termios, old, 300, 115200);
 401         baud = msm_set_baud_rate(port, baud);
 402         if (tty_termios_baud_rate(termios))
 403                 tty_termios_encode_baud_rate(termios, baud, baud);
 404
 405         /* calculate parity */
 406         mr = msm_read(port, UART_MR2);
 407         mr &= ~UART_MR2_PARITY_MODE;
 408         if (termios->c_cflag & PARENB) {
 409                 if (termios->c_cflag & PARODD)
 410                         mr |= UART_MR2_PARITY_MODE_ODD;
 411                 else if (termios->c_cflag & CMSPAR)
 412                         mr |= UART_MR2_PARITY_MODE_SPACE;
 413                 else
 414                         mr |= UART_MR2_PARITY_MODE_EVEN;
 415         }
 416
 417         /* calculate bits per char */
 418         mr &= ~UART_MR2_BITS_PER_CHAR;
 419         switch (termios->c_cflag & CSIZE) {
 420         case CS5:
 421                 mr |= UART_MR2_BITS_PER_CHAR_5;
 422                 break;
 423         case CS6:
 424                 mr |= UART_MR2_BITS_PER_CHAR_6;
 425                 break;
 426         case CS7:
 427                 mr |= UART_MR2_BITS_PER_CHAR_7;
 428                 break;
 429         case CS8:
 430         default:
 431                 mr |= UART_MR2_BITS_PER_CHAR_8;
 432                 break;
 433         }
 434
 435         /* calculate stop bits */
 436         mr &= ~(UART_MR2_STOP_BIT_LEN_ONE | UART_MR2_STOP_BIT_LEN_TWO);
 437         if (termios->c_cflag & CSTOPB)
 438                 mr |= UART_MR2_STOP_BIT_LEN_TWO;
 439         else
 440                 mr |= UART_MR2_STOP_BIT_LEN_ONE;
 441
 442         /* set parity, bits per char, and stop bit */
 443         msm_write(port, mr, UART_MR2);
 444
 445         /* calculate and set hardware flow control */
 446         mr = msm_read(port, UART_MR1);
 447         mr &= ~(UART_MR1_CTS_CTL | UART_MR1_RX_RDY_CTL);
 448         if (termios->c_cflag & CRTSCTS) {
 449                 mr |= UART_MR1_CTS_CTL;
 450                 mr |= UART_MR1_RX_RDY_CTL;
 451         }
 452         msm_write(port, mr, UART_MR1);
 453
 454         /* Configure status bits to ignore based on termio flags. */
 455         port->read_status_mask = 0;
 456         if (termios->c_iflag & INPCK)
 457                 port->read_status_mask |= UART_SR_PAR_FRAME_ERR;
 458         if (termios->c_iflag & (BRKINT | PARMRK))
 459                 port->read_status_mask |= UART_SR_RX_BREAK;
 460
 461         uart_update_timeout(port, termios->c_cflag, baud);
 462
 463         spin_unlock_irqrestore(&port->lock, flags);
 464 }
 465
 466 static const char *msm_type(struct uart_port *port)
 467 {
 468         return "MSM";
 469 }
 470
 471 static void msm_release_port(struct uart_port *port)
 472 {
 473         struct platform_device *pdev = to_platform_device(port->dev);
 474         struct resource *resource;
 475         resource_size_t size;
 476
 477         resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 478         if (unlikely(!resource))
 479                 return;
 480         size = resource->end - resource->start + 1;
 481
 482         release_mem_region(port->mapbase, size);
 483         iounmap(port->membase);
 484         port->membase = NULL;
 485 }
 486
 487 static int msm_request_port(struct uart_port *port)
 488 {
 489         struct platform_device *pdev = to_platform_device(port->dev);
 490         struct resource *resource;
 491         resource_size_t size;
 492
 493         resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 494         if (unlikely(!resource))
 495                 return -ENXIO;
 496         size = resource->end - resource->start + 1;
 497
 498         if (unlikely(!request_mem_region(port->mapbase, size, "msm_serial")))
 499                 return -EBUSY;
 500
 501         port->membase = ioremap(port->mapbase, size);
 502         if (!port->membase) {
 503                 release_mem_region(port->mapbase, size);
 504                 return -EBUSY;
 505         }
 506
 507         return 0;
 508 }
 509
 510 static void msm_config_port(struct uart_port *port, int flags)
 511 {
 512         if (flags & UART_CONFIG_TYPE) {
 513                 port->type = PORT_MSM;
 514                 msm_request_port(port);
 515         }
 516 }
 517
 518 static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
 519 {
 520         if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
 521                 return -EINVAL;
 522         if (unlikely(port->irq != ser->irq))
 523                 return -EINVAL;
 524         return 0;
 525 }
 526
 527 static void msm_power(struct uart_port *port, unsigned int state,
 528                       unsigned int oldstate)
 529 {
 530         struct msm_port *msm_port = UART_TO_MSM(port);
 531
 532         switch (state) {
 533         case 0:
 534                 clk_enable(msm_port->clk);
 535                 break;
 536         case 3:
 537                 clk_disable(msm_port->clk);
 538                 break;
 539         default:
 540                 printk(KERN_ERR "msm_serial: Unknown PM state %d\n", state);
 541         }
 542 }
 543
 544 static struct uart_ops msm_uart_pops = {
 545         .tx_empty = msm_tx_empty,
 546         .set_mctrl = msm_set_mctrl,
 547         .get_mctrl = msm_get_mctrl,
 548         .stop_tx = msm_stop_tx,
 549         .start_tx = msm_start_tx,
 550         .stop_rx = msm_stop_rx,
 551         .enable_ms = msm_enable_ms,
 552         .break_ctl = msm_break_ctl,
 553         .startup = msm_startup,
 554         .shutdown = msm_shutdown,
 555         .set_termios = msm_set_termios,
 556         .type = msm_type,
 557         .release_port = msm_release_port,
 558         .request_port = msm_request_port,
 559         .config_port = msm_config_port,
 560         .verify_port = msm_verify_port,
 561         .pm = msm_power,
 562 };
 563
 564 static struct msm_port msm_uart_ports[] = {
 565         {
 566                 .uart = {
 567                         .iotype = UPIO_MEM,
 568                         .ops = &msm_uart_pops,
 569                         .flags = UPF_BOOT_AUTOCONF,
 570                         .fifosize = 512,
 571                         .line = 0,
 572                 },
 573         },
 574         {
 575                 .uart = {
 576                         .iotype = UPIO_MEM,
 577                         .ops = &msm_uart_pops,
 578                         .flags = UPF_BOOT_AUTOCONF,
 579                         .fifosize = 512,
 580                         .line = 1,
 581                 },
 582         },
 583         {
 584                 .uart = {
 585                         .iotype = UPIO_MEM,
 586                         .ops = &msm_uart_pops,
 587                         .flags = UPF_BOOT_AUTOCONF,
 588                         .fifosize = 64,
 589                         .line = 2,
 590                 },
 591         },
 592 };
 593
 594 #define UART_NR ARRAY_SIZE(msm_uart_ports)
 595
 596 static inline struct uart_port *get_port_from_line(unsigned int line)
 597 {
 598         return &msm_uart_ports[line].uart;
 599 }
 600
 601 #ifdef CONFIG_SERIAL_MSM_CONSOLE
 602
 603 static void msm_console_putchar(struct uart_port *port, int c)
 604 {
 605         while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
 606                 ;
 607         msm_write(port, c, UART_TF);
 608 }
 609
 610 static void msm_console_write(struct console *co, const char *s,
 611                               unsigned int count)
 612 {
 613         struct uart_port *port;
 614         struct msm_port *msm_port;
 615
 616         BUG_ON(co->index < 0 || co->index >= UART_NR);
 617
 618         port = get_port_from_line(co->index);
 619         msm_port = UART_TO_MSM(port);
 620
 621         spin_lock(&port->lock);
 622         uart_console_write(port, s, count, msm_console_putchar);
 623         spin_unlock(&port->lock);
 624 }
 625
 626 static int __init msm_console_setup(struct console *co, char *options)
 627 {
 628         struct uart_port *port;
 629         int baud, flow, bits, parity;
 630
 631         if (unlikely(co->index >= UART_NR || co->index < 0))
 632                 return -ENXIO;
 633
 634         port = get_port_from_line(co->index);
 635
 636         if (unlikely(!port->membase))
 637                 return -ENXIO;
 638
 639         port->cons = co;
 640
 641         msm_init_clock(port);
 642
 643         if (options)
 644                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 645
 646         bits = 8;
 647         parity = 'n';
 648         flow = 'n';
 649         msm_write(port, UART_MR2_BITS_PER_CHAR_8 | UART_MR2_STOP_BIT_LEN_ONE,
 650                   UART_MR2);    /* 8N1 */
 651
 652         if (baud < 300 || baud > 115200)
 653                 baud = 115200;
 654         msm_set_baud_rate(port, baud);
 655
 656         msm_reset(port);
 657
 658         printk(KERN_INFO "msm_serial: console setup on port #%d\n", port->line);
 659
 660         return uart_set_options(port, co, baud, parity, bits, flow);
 661 }
 662
 663 static struct uart_driver msm_uart_driver;
 664
 665 static struct console msm_console = {
 666         .name = "ttyMSM",
 667         .write = msm_console_write,
 668         .device = uart_console_device,
 669         .setup = msm_console_setup,
 670         .flags = CON_PRINTBUFFER,
 671         .index = -1,
 672         .data = &msm_uart_driver,
 673 };
 674
 675 #define MSM_CONSOLE     (&msm_console)
 676
 677 #else
 678 #define MSM_CONSOLE     NULL
 679 #endif
 680
 681 static struct uart_driver msm_uart_driver = {
 682         .owner = THIS_MODULE,
 683         .driver_name = "msm_serial",
 684         .dev_name = "ttyMSM",
 685         .nr = UART_NR,
 686         .cons = MSM_CONSOLE,
 687 };
 688
 689 static int __init msm_serial_probe(struct platform_device *pdev)
 690 {
 691         struct msm_port *msm_port;
 692         struct resource *resource;
 693         struct uart_port *port;
 694
 695         if (unlikely(pdev->id < 0 || pdev->id >= UART_NR))
 696                 return -ENXIO;
 697
 698         printk(KERN_INFO "msm_serial: detected port #%d\n", pdev->id);
 699
 700         port = get_port_from_line(pdev->id);
 701         port->dev = &pdev->dev;
 702         msm_port = UART_TO_MSM(port);
 703
 704         msm_port->clk = clk_get(&pdev->dev, "uart_clk");
 705         if (unlikely(IS_ERR(msm_port->clk)))
 706                 return PTR_ERR(msm_port->clk);
 707         port->uartclk = clk_get_rate(msm_port->clk);
 708
 709         resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 710         if (unlikely(!resource))
 711                 return -ENXIO;
 712         port->mapbase = resource->start;
 713
 714         port->irq = platform_get_irq(pdev, 0);
 715         if (unlikely(port->irq < 0))
 716                 return -ENXIO;
 717
 718         platform_set_drvdata(pdev, port);
 719
 720         return uart_add_one_port(&msm_uart_driver, port);
 721 }
 722
 723 static int __devexit msm_serial_remove(struct platform_device *pdev)
 724 {
 725         struct msm_port *msm_port = platform_get_drvdata(pdev);
 726
 727         clk_put(msm_port->clk);
 728
 729         return 0;
 730 }
 731
 732 static struct platform_driver msm_platform_driver = {
 733         .probe = msm_serial_probe,
 734         .remove = msm_serial_remove,
 735         .driver = {
 736                 .name = "msm_serial",
 737                 .owner = THIS_MODULE,
 738         },
 739 };
 740
 741 static int __init msm_serial_init(void)
 742 {
 743         int ret;
 744
 745         ret = uart_register_driver(&msm_uart_driver);
 746         if (unlikely(ret))
 747                 return ret;
 748
 749         ret = platform_driver_probe(&msm_platform_driver, msm_serial_probe);
 750         if (unlikely(ret))
 751                 uart_unregister_driver(&msm_uart_driver);
 752
 753         printk(KERN_INFO "msm_serial: driver initialized\n");
 754
 755         return ret;
 756 }
 757
 758 static void __exit msm_serial_exit(void)
 759 {
 760 #ifdef CONFIG_SERIAL_MSM_CONSOLE
 761         unregister_console(&msm_console);
 762 #endif
 763         platform_driver_unregister(&msm_platform_driver);
 764         uart_unregister_driver(&msm_uart_driver);
 765 }
 766
 767 module_init(msm_serial_init);
 768 module_exit(msm_serial_exit);
 769
 770 MODULE_AUTHOR("Robert Love <rlove@google.com>");
 771 MODULE_DESCRIPTION("Driver for msm7x serial device");
 772 MODULE_LICENSE("GPL");