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