drivers/tty/serial/samsung.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Driver core for Samsung SoC onboard UARTs.
   4  *
   5  * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
   6  *      http://armlinux.simtec.co.uk/
   7 */
   8
   9 /* Hote on 2410 error handling
  10  *
  11  * The s3c2410 manual has a love/hate affair with the contents of the
  12  * UERSTAT register in the UART blocks, and keeps marking some of the
  13  * error bits as reserved. Having checked with the s3c2410x01,
  14  * it copes with BREAKs properly, so I am happy to ignore the RESERVED
  15  * feature from the latter versions of the manual.
  16  *
  17  * If it becomes aparrent that latter versions of the 2410 remove these
  18  * bits, then action will have to be taken to differentiate the versions
  19  * and change the policy on BREAK
  20  *
  21  * BJD, 04-Nov-2004
  22 */
  23
  24 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  25 #define SUPPORT_SYSRQ
  26 #endif
  27
  28 #include <linux/dmaengine.h>
  29 #include <linux/dma-mapping.h>
  30 #include <linux/slab.h>
  31 #include <linux/module.h>
  32 #include <linux/ioport.h>
  33 #include <linux/io.h>
  34 #include <linux/platform_device.h>
  35 #include <linux/init.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/console.h>
  38 #include <linux/tty.h>
  39 #include <linux/tty_flip.h>
  40 #include <linux/serial_core.h>
  41 #include <linux/serial.h>
  42 #include <linux/serial_s3c.h>
  43 #include <linux/delay.h>
  44 #include <linux/clk.h>
  45 #include <linux/cpufreq.h>
  46 #include <linux/of.h>
  47
  48 #include <asm/irq.h>
  49
  50 #include "samsung.h"
  51
  52 #if     defined(CONFIG_SERIAL_SAMSUNG_DEBUG) && \
  53         !defined(MODULE)
  54
  55 extern void printascii(const char *);
  56
  57 __printf(1, 2)
  58 static void dbg(const char *fmt, ...)
  59 {
  60         va_list va;
  61         char buff[256];
  62
  63         va_start(va, fmt);
  64         vscnprintf(buff, sizeof(buff), fmt, va);
  65         va_end(va);
  66
  67         printascii(buff);
  68 }
  69
  70 #else
  71 #define dbg(fmt, ...) do { if (0) no_printk(fmt, ##__VA_ARGS__); } while (0)
  72 #endif
  73
  74 /* UART name and device definitions */
  75
  76 #define S3C24XX_SERIAL_NAME     "ttySAC"
  77 #define S3C24XX_SERIAL_MAJOR    204
  78 #define S3C24XX_SERIAL_MINOR    64
  79
  80 #define S3C24XX_TX_PIO                  1
  81 #define S3C24XX_TX_DMA                  2
  82 #define S3C24XX_RX_PIO                  1
  83 #define S3C24XX_RX_DMA                  2
  84 /* macros to change one thing to another */
  85
  86 #define tx_enabled(port) ((port)->unused[0])
  87 #define rx_enabled(port) ((port)->unused[1])
  88
  89 /* flag to ignore all characters coming in */
  90 #define RXSTAT_DUMMY_READ (0x10000000)
  91
  92 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
  93 {
  94         return container_of(port, struct s3c24xx_uart_port, port);
  95 }
  96
  97 /* translate a port to the device name */
  98
  99 static inline const char *s3c24xx_serial_portname(struct uart_port *port)
 100 {
 101         return to_platform_device(port->dev)->name;
 102 }
 103
 104 static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
 105 {
 106         return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
 107 }
 108
 109 /*
 110  * s3c64xx and later SoC's include the interrupt mask and status registers in
 111  * the controller itself, unlike the s3c24xx SoC's which have these registers
 112  * in the interrupt controller. Check if the port type is s3c64xx or higher.
 113  */
 114 static int s3c24xx_serial_has_interrupt_mask(struct uart_port *port)
 115 {
 116         return to_ourport(port)->info->type == PORT_S3C6400;
 117 }
 118
 119 static void s3c24xx_serial_rx_enable(struct uart_port *port)
 120 {
 121         unsigned long flags;
 122         unsigned int ucon, ufcon;
 123         int count = 10000;
 124
 125         spin_lock_irqsave(&port->lock, flags);
 126
 127         while (--count && !s3c24xx_serial_txempty_nofifo(port))
 128                 udelay(100);
 129
 130         ufcon = rd_regl(port, S3C2410_UFCON);
 131         ufcon |= S3C2410_UFCON_RESETRX;
 132         wr_regl(port, S3C2410_UFCON, ufcon);
 133
 134         ucon = rd_regl(port, S3C2410_UCON);
 135         ucon |= S3C2410_UCON_RXIRQMODE;
 136         wr_regl(port, S3C2410_UCON, ucon);
 137
 138         rx_enabled(port) = 1;
 139         spin_unlock_irqrestore(&port->lock, flags);
 140 }
 141
 142 static void s3c24xx_serial_rx_disable(struct uart_port *port)
 143 {
 144         unsigned long flags;
 145         unsigned int ucon;
 146
 147         spin_lock_irqsave(&port->lock, flags);
 148
 149         ucon = rd_regl(port, S3C2410_UCON);
 150         ucon &= ~S3C2410_UCON_RXIRQMODE;
 151         wr_regl(port, S3C2410_UCON, ucon);
 152
 153         rx_enabled(port) = 0;
 154         spin_unlock_irqrestore(&port->lock, flags);
 155 }
 156
 157 static void s3c24xx_serial_stop_tx(struct uart_port *port)
 158 {
 159         struct s3c24xx_uart_port *ourport = to_ourport(port);
 160         struct s3c24xx_uart_dma *dma = ourport->dma;
 161         struct circ_buf *xmit = &port->state->xmit;
 162         struct dma_tx_state state;
 163         int count;
 164
 165         if (!tx_enabled(port))
 166                 return;
 167
 168         if (s3c24xx_serial_has_interrupt_mask(port))
 169                 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
 170         else
 171                 disable_irq_nosync(ourport->tx_irq);
 172
 173         if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
 174                 dmaengine_pause(dma->tx_chan);
 175                 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
 176                 dmaengine_terminate_all(dma->tx_chan);
 177                 dma_sync_single_for_cpu(ourport->port.dev,
 178                         dma->tx_transfer_addr, dma->tx_size, DMA_TO_DEVICE);
 179                 async_tx_ack(dma->tx_desc);
 180                 count = dma->tx_bytes_requested - state.residue;
 181                 xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
 182                 port->icount.tx += count;
 183         }
 184
 185         tx_enabled(port) = 0;
 186         ourport->tx_in_progress = 0;
 187
 188         if (port->flags & UPF_CONS_FLOW)
 189                 s3c24xx_serial_rx_enable(port);
 190
 191         ourport->tx_mode = 0;
 192 }
 193
 194 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
 195
 196 static void s3c24xx_serial_tx_dma_complete(void *args)
 197 {
 198         struct s3c24xx_uart_port *ourport = args;
 199         struct uart_port *port = &ourport->port;
 200         struct circ_buf *xmit = &port->state->xmit;
 201         struct s3c24xx_uart_dma *dma = ourport->dma;
 202         struct dma_tx_state state;
 203         unsigned long flags;
 204         int count;
 205
 206
 207         dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
 208         count = dma->tx_bytes_requested - state.residue;
 209         async_tx_ack(dma->tx_desc);
 210
 211         dma_sync_single_for_cpu(ourport->port.dev, dma->tx_transfer_addr,
 212                                 dma->tx_size, DMA_TO_DEVICE);
 213
 214         spin_lock_irqsave(&port->lock, flags);
 215
 216         xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
 217         port->icount.tx += count;
 218         ourport->tx_in_progress = 0;
 219
 220         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 221                 uart_write_wakeup(port);
 222
 223         s3c24xx_serial_start_next_tx(ourport);
 224         spin_unlock_irqrestore(&port->lock, flags);
 225 }
 226
 227 static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
 228 {
 229         struct uart_port *port = &ourport->port;
 230         u32 ucon;
 231
 232         /* Mask Tx interrupt */
 233         if (s3c24xx_serial_has_interrupt_mask(port))
 234                 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
 235         else
 236                 disable_irq_nosync(ourport->tx_irq);
 237
 238         /* Enable tx dma mode */
 239         ucon = rd_regl(port, S3C2410_UCON);
 240         ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
 241         ucon |= (dma_get_cache_alignment() >= 16) ?
 242                 S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1;
 243         ucon |= S3C64XX_UCON_TXMODE_DMA;
 244         wr_regl(port,  S3C2410_UCON, ucon);
 245
 246         ourport->tx_mode = S3C24XX_TX_DMA;
 247 }
 248
 249 static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
 250 {
 251         struct uart_port *port = &ourport->port;
 252         u32 ucon, ufcon;
 253
 254         /* Set ufcon txtrig */
 255         ourport->tx_in_progress = S3C24XX_TX_PIO;
 256         ufcon = rd_regl(port, S3C2410_UFCON);
 257         wr_regl(port,  S3C2410_UFCON, ufcon);
 258
 259         /* Enable tx pio mode */
 260         ucon = rd_regl(port, S3C2410_UCON);
 261         ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
 262         ucon |= S3C64XX_UCON_TXMODE_CPU;
 263         wr_regl(port,  S3C2410_UCON, ucon);
 264
 265         /* Unmask Tx interrupt */
 266         if (s3c24xx_serial_has_interrupt_mask(port))
 267                 s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
 268                                   S3C64XX_UINTM);
 269         else
 270                 enable_irq(ourport->tx_irq);
 271
 272         ourport->tx_mode = S3C24XX_TX_PIO;
 273 }
 274
 275 static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
 276 {
 277         if (ourport->tx_mode != S3C24XX_TX_PIO)
 278                 enable_tx_pio(ourport);
 279 }
 280
 281 static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
 282                                       unsigned int count)
 283 {
 284         struct uart_port *port = &ourport->port;
 285         struct circ_buf *xmit = &port->state->xmit;
 286         struct s3c24xx_uart_dma *dma = ourport->dma;
 287
 288
 289         if (ourport->tx_mode != S3C24XX_TX_DMA)
 290                 enable_tx_dma(ourport);
 291
 292         dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
 293         dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
 294
 295         dma_sync_single_for_device(ourport->port.dev, dma->tx_transfer_addr,
 296                                 dma->tx_size, DMA_TO_DEVICE);
 297
 298         dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
 299                                 dma->tx_transfer_addr, dma->tx_size,
 300                                 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
 301         if (!dma->tx_desc) {
 302                 dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
 303                 return -EIO;
 304         }
 305
 306         dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
 307         dma->tx_desc->callback_param = ourport;
 308         dma->tx_bytes_requested = dma->tx_size;
 309
 310         ourport->tx_in_progress = S3C24XX_TX_DMA;
 311         dma->tx_cookie = dmaengine_submit(dma->tx_desc);
 312         dma_async_issue_pending(dma->tx_chan);
 313         return 0;
 314 }
 315
 316 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
 317 {
 318         struct uart_port *port = &ourport->port;
 319         struct circ_buf *xmit = &port->state->xmit;
 320         unsigned long count;
 321
 322         /* Get data size up to the end of buffer */
 323         count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 324
 325         if (!count) {
 326                 s3c24xx_serial_stop_tx(port);
 327                 return;
 328         }
 329
 330         if (!ourport->dma || !ourport->dma->tx_chan ||
 331             count < ourport->min_dma_size ||
 332             xmit->tail & (dma_get_cache_alignment() - 1))
 333                 s3c24xx_serial_start_tx_pio(ourport);
 334         else
 335                 s3c24xx_serial_start_tx_dma(ourport, count);
 336 }
 337
 338 static void s3c24xx_serial_start_tx(struct uart_port *port)
 339 {
 340         struct s3c24xx_uart_port *ourport = to_ourport(port);
 341         struct circ_buf *xmit = &port->state->xmit;
 342
 343         if (!tx_enabled(port)) {
 344                 if (port->flags & UPF_CONS_FLOW)
 345                         s3c24xx_serial_rx_disable(port);
 346
 347                 tx_enabled(port) = 1;
 348                 if (!ourport->dma || !ourport->dma->tx_chan)
 349                         s3c24xx_serial_start_tx_pio(ourport);
 350         }
 351
 352         if (ourport->dma && ourport->dma->tx_chan) {
 353                 if (!uart_circ_empty(xmit) && !ourport->tx_in_progress)
 354                         s3c24xx_serial_start_next_tx(ourport);
 355         }
 356 }
 357
 358 static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
 359                 struct tty_port *tty, int count)
 360 {
 361         struct s3c24xx_uart_dma *dma = ourport->dma;
 362         int copied;
 363
 364         if (!count)
 365                 return;
 366
 367         dma_sync_single_for_cpu(ourport->port.dev, dma->rx_addr,
 368                                 dma->rx_size, DMA_FROM_DEVICE);
 369
 370         ourport->port.icount.rx += count;
 371         if (!tty) {
 372                 dev_err(ourport->port.dev, "No tty port\n");
 373                 return;
 374         }
 375         copied = tty_insert_flip_string(tty,
 376                         ((unsigned char *)(ourport->dma->rx_buf)), count);
 377         if (copied != count) {
 378                 WARN_ON(1);
 379                 dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
 380         }
 381 }
 382
 383 static void s3c24xx_serial_stop_rx(struct uart_port *port)
 384 {
 385         struct s3c24xx_uart_port *ourport = to_ourport(port);
 386         struct s3c24xx_uart_dma *dma = ourport->dma;
 387         struct tty_port *t = &port->state->port;
 388         struct dma_tx_state state;
 389         enum dma_status dma_status;
 390         unsigned int received;
 391
 392         if (rx_enabled(port)) {
 393                 dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
 394                 if (s3c24xx_serial_has_interrupt_mask(port))
 395                         s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
 396                                         S3C64XX_UINTM);
 397                 else
 398                         disable_irq_nosync(ourport->rx_irq);
 399                 rx_enabled(port) = 0;
 400         }
 401         if (dma && dma->rx_chan) {
 402                 dmaengine_pause(dma->tx_chan);
 403                 dma_status = dmaengine_tx_status(dma->rx_chan,
 404                                 dma->rx_cookie, &state);
 405                 if (dma_status == DMA_IN_PROGRESS ||
 406                         dma_status == DMA_PAUSED) {
 407                         received = dma->rx_bytes_requested - state.residue;
 408                         dmaengine_terminate_all(dma->rx_chan);
 409                         s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
 410                 }
 411         }
 412 }
 413
 414 static inline struct s3c24xx_uart_info
 415         *s3c24xx_port_to_info(struct uart_port *port)
 416 {
 417         return to_ourport(port)->info;
 418 }
 419
 420 static inline struct s3c2410_uartcfg
 421         *s3c24xx_port_to_cfg(struct uart_port *port)
 422 {
 423         struct s3c24xx_uart_port *ourport;
 424
 425         if (port->dev == NULL)
 426                 return NULL;
 427
 428         ourport = container_of(port, struct s3c24xx_uart_port, port);
 429         return ourport->cfg;
 430 }
 431
 432 static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
 433                                      unsigned long ufstat)
 434 {
 435         struct s3c24xx_uart_info *info = ourport->info;
 436
 437         if (ufstat & info->rx_fifofull)
 438                 return ourport->port.fifosize;
 439
 440         return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
 441 }
 442
 443 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
 444 static void s3c24xx_serial_rx_dma_complete(void *args)
 445 {
 446         struct s3c24xx_uart_port *ourport = args;
 447         struct uart_port *port = &ourport->port;
 448
 449         struct s3c24xx_uart_dma *dma = ourport->dma;
 450         struct tty_port *t = &port->state->port;
 451         struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
 452
 453         struct dma_tx_state state;
 454         unsigned long flags;
 455         int received;
 456
 457         dmaengine_tx_status(dma->rx_chan,  dma->rx_cookie, &state);
 458         received  = dma->rx_bytes_requested - state.residue;
 459         async_tx_ack(dma->rx_desc);
 460
 461         spin_lock_irqsave(&port->lock, flags);
 462
 463         if (received)
 464                 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
 465
 466         if (tty) {
 467                 tty_flip_buffer_push(t);
 468                 tty_kref_put(tty);
 469         }
 470
 471         s3c64xx_start_rx_dma(ourport);
 472
 473         spin_unlock_irqrestore(&port->lock, flags);
 474 }
 475
 476 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
 477 {
 478         struct s3c24xx_uart_dma *dma = ourport->dma;
 479
 480         dma_sync_single_for_device(ourport->port.dev, dma->rx_addr,
 481                                 dma->rx_size, DMA_FROM_DEVICE);
 482
 483         dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
 484                                 dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
 485                                 DMA_PREP_INTERRUPT);
 486         if (!dma->rx_desc) {
 487                 dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
 488                 return;
 489         }
 490
 491         dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
 492         dma->rx_desc->callback_param = ourport;
 493         dma->rx_bytes_requested = dma->rx_size;
 494
 495         dma->rx_cookie = dmaengine_submit(dma->rx_desc);
 496         dma_async_issue_pending(dma->rx_chan);
 497 }
 498
 499 /* ? - where has parity gone?? */
 500 #define S3C2410_UERSTAT_PARITY (0x1000)
 501
 502 static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
 503 {
 504         struct uart_port *port = &ourport->port;
 505         unsigned int ucon;
 506
 507         /* set Rx mode to DMA mode */
 508         ucon = rd_regl(port, S3C2410_UCON);
 509         ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
 510                         S3C64XX_UCON_TIMEOUT_MASK |
 511                         S3C64XX_UCON_EMPTYINT_EN |
 512                         S3C64XX_UCON_DMASUS_EN |
 513                         S3C64XX_UCON_TIMEOUT_EN |
 514                         S3C64XX_UCON_RXMODE_MASK);
 515         ucon |= S3C64XX_UCON_RXBURST_16 |
 516                         0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
 517                         S3C64XX_UCON_EMPTYINT_EN |
 518                         S3C64XX_UCON_TIMEOUT_EN |
 519                         S3C64XX_UCON_RXMODE_DMA;
 520         wr_regl(port, S3C2410_UCON, ucon);
 521
 522         ourport->rx_mode = S3C24XX_RX_DMA;
 523 }
 524
 525 static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
 526 {
 527         struct uart_port *port = &ourport->port;
 528         unsigned int ucon;
 529
 530         /* set Rx mode to DMA mode */
 531         ucon = rd_regl(port, S3C2410_UCON);
 532         ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
 533                         S3C64XX_UCON_EMPTYINT_EN |
 534                         S3C64XX_UCON_DMASUS_EN |
 535                         S3C64XX_UCON_TIMEOUT_EN |
 536                         S3C64XX_UCON_RXMODE_MASK);
 537         ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
 538                         S3C64XX_UCON_TIMEOUT_EN |
 539                         S3C64XX_UCON_RXMODE_CPU;
 540         wr_regl(port, S3C2410_UCON, ucon);
 541
 542         ourport->rx_mode = S3C24XX_RX_PIO;
 543 }
 544
 545 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
 546
 547 static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
 548 {
 549         unsigned int utrstat, ufstat, received;
 550         struct s3c24xx_uart_port *ourport = dev_id;
 551         struct uart_port *port = &ourport->port;
 552         struct s3c24xx_uart_dma *dma = ourport->dma;
 553         struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
 554         struct tty_port *t = &port->state->port;
 555         unsigned long flags;
 556         struct dma_tx_state state;
 557
 558         utrstat = rd_regl(port, S3C2410_UTRSTAT);
 559         ufstat = rd_regl(port, S3C2410_UFSTAT);
 560
 561         spin_lock_irqsave(&port->lock, flags);
 562
 563         if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
 564                 s3c64xx_start_rx_dma(ourport);
 565                 if (ourport->rx_mode == S3C24XX_RX_PIO)
 566                         enable_rx_dma(ourport);
 567                 goto finish;
 568         }
 569
 570         if (ourport->rx_mode == S3C24XX_RX_DMA) {
 571                 dmaengine_pause(dma->rx_chan);
 572                 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
 573                 dmaengine_terminate_all(dma->rx_chan);
 574                 received = dma->rx_bytes_requested - state.residue;
 575                 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
 576
 577                 enable_rx_pio(ourport);
 578         }
 579
 580         s3c24xx_serial_rx_drain_fifo(ourport);
 581
 582         if (tty) {
 583                 tty_flip_buffer_push(t);
 584                 tty_kref_put(tty);
 585         }
 586
 587         wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
 588
 589 finish:
 590         spin_unlock_irqrestore(&port->lock, flags);
 591
 592         return IRQ_HANDLED;
 593 }
 594
 595 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
 596 {
 597         struct uart_port *port = &ourport->port;
 598         unsigned int ufcon, ch, flag, ufstat, uerstat;
 599         unsigned int fifocnt = 0;
 600         int max_count = port->fifosize;
 601
 602         while (max_count-- > 0) {
 603                 /*
 604                  * Receive all characters known to be in FIFO
 605                  * before reading FIFO level again
 606                  */
 607                 if (fifocnt == 0) {
 608                         ufstat = rd_regl(port, S3C2410_UFSTAT);
 609                         fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
 610                         if (fifocnt == 0)
 611                                 break;
 612                 }
 613                 fifocnt--;
 614
 615                 uerstat = rd_regl(port, S3C2410_UERSTAT);
 616                 ch = rd_regb(port, S3C2410_URXH);
 617
 618                 if (port->flags & UPF_CONS_FLOW) {
 619                         int txe = s3c24xx_serial_txempty_nofifo(port);
 620
 621                         if (rx_enabled(port)) {
 622                                 if (!txe) {
 623                                         rx_enabled(port) = 0;
 624                                         continue;
 625                                 }
 626                         } else {
 627                                 if (txe) {
 628                                         ufcon = rd_regl(port, S3C2410_UFCON);
 629                                         ufcon |= S3C2410_UFCON_RESETRX;
 630                                         wr_regl(port, S3C2410_UFCON, ufcon);
 631                                         rx_enabled(port) = 1;
 632                                         return;
 633                                 }
 634                                 continue;
 635                         }
 636                 }
 637
 638                 /* insert the character into the buffer */
 639
 640                 flag = TTY_NORMAL;
 641                 port->icount.rx++;
 642
 643                 if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
 644                         dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
 645                             ch, uerstat);
 646
 647                         /* check for break */
 648                         if (uerstat & S3C2410_UERSTAT_BREAK) {
 649                                 dbg("break!\n");
 650                                 port->icount.brk++;
 651                                 if (uart_handle_break(port))
 652                                         continue; /* Ignore character */
 653                         }
 654
 655                         if (uerstat & S3C2410_UERSTAT_FRAME)
 656                                 port->icount.frame++;
 657                         if (uerstat & S3C2410_UERSTAT_OVERRUN)
 658                                 port->icount.overrun++;
 659
 660                         uerstat &= port->read_status_mask;
 661
 662                         if (uerstat & S3C2410_UERSTAT_BREAK)
 663                                 flag = TTY_BREAK;
 664                         else if (uerstat & S3C2410_UERSTAT_PARITY)
 665                                 flag = TTY_PARITY;
 666                         else if (uerstat & (S3C2410_UERSTAT_FRAME |
 667                                             S3C2410_UERSTAT_OVERRUN))
 668                                 flag = TTY_FRAME;
 669                 }
 670
 671                 if (uart_handle_sysrq_char(port, ch))
 672                         continue; /* Ignore character */
 673
 674                 uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
 675                                  ch, flag);
 676         }
 677
 678         tty_flip_buffer_push(&port->state->port);
 679 }
 680
 681 static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
 682 {
 683         struct s3c24xx_uart_port *ourport = dev_id;
 684         struct uart_port *port = &ourport->port;
 685         unsigned long flags;
 686
 687         spin_lock_irqsave(&port->lock, flags);
 688         s3c24xx_serial_rx_drain_fifo(ourport);
 689         spin_unlock_irqrestore(&port->lock, flags);
 690
 691         return IRQ_HANDLED;
 692 }
 693
 694
 695 static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id)
 696 {
 697         struct s3c24xx_uart_port *ourport = dev_id;
 698
 699         if (ourport->dma && ourport->dma->rx_chan)
 700                 return s3c24xx_serial_rx_chars_dma(dev_id);
 701         return s3c24xx_serial_rx_chars_pio(dev_id);
 702 }
 703
 704 static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
 705 {
 706         struct s3c24xx_uart_port *ourport = id;
 707         struct uart_port *port = &ourport->port;
 708         struct circ_buf *xmit = &port->state->xmit;
 709         unsigned long flags;
 710         int count, dma_count = 0;
 711
 712         spin_lock_irqsave(&port->lock, flags);
 713
 714         count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 715
 716         if (ourport->dma && ourport->dma->tx_chan &&
 717             count >= ourport->min_dma_size) {
 718                 int align = dma_get_cache_alignment() -
 719                         (xmit->tail & (dma_get_cache_alignment() - 1));
 720                 if (count-align >= ourport->min_dma_size) {
 721                         dma_count = count-align;
 722                         count = align;
 723                 }
 724         }
 725
 726         if (port->x_char) {
 727                 wr_regb(port, S3C2410_UTXH, port->x_char);
 728                 port->icount.tx++;
 729                 port->x_char = 0;
 730                 goto out;
 731         }
 732
 733         /* if there isn't anything more to transmit, or the uart is now
 734          * stopped, disable the uart and exit
 735         */
 736
 737         if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
 738                 s3c24xx_serial_stop_tx(port);
 739                 goto out;
 740         }
 741
 742         /* try and drain the buffer... */
 743
 744         if (count > port->fifosize) {
 745                 count = port->fifosize;
 746                 dma_count = 0;
 747         }
 748
 749         while (!uart_circ_empty(xmit) && count > 0) {
 750                 if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
 751                         break;
 752
 753                 wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
 754                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 755                 port->icount.tx++;
 756                 count--;
 757         }
 758
 759         if (!count && dma_count) {
 760                 s3c24xx_serial_start_tx_dma(ourport, dma_count);
 761                 goto out;
 762         }
 763
 764         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
 765                 spin_unlock(&port->lock);
 766                 uart_write_wakeup(port);
 767                 spin_lock(&port->lock);
 768         }
 769
 770         if (uart_circ_empty(xmit))
 771                 s3c24xx_serial_stop_tx(port);
 772
 773 out:
 774         spin_unlock_irqrestore(&port->lock, flags);
 775         return IRQ_HANDLED;
 776 }
 777
 778 /* interrupt handler for s3c64xx and later SoC's.*/
 779 static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
 780 {
 781         struct s3c24xx_uart_port *ourport = id;
 782         struct uart_port *port = &ourport->port;
 783         unsigned int pend = rd_regl(port, S3C64XX_UINTP);
 784         irqreturn_t ret = IRQ_HANDLED;
 785
 786         if (pend & S3C64XX_UINTM_RXD_MSK) {
 787                 ret = s3c24xx_serial_rx_chars(irq, id);
 788                 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
 789         }
 790         if (pend & S3C64XX_UINTM_TXD_MSK) {
 791                 ret = s3c24xx_serial_tx_chars(irq, id);
 792                 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
 793         }
 794         return ret;
 795 }
 796
 797 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
 798 {
 799         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
 800         unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
 801         unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
 802
 803         if (ufcon & S3C2410_UFCON_FIFOMODE) {
 804                 if ((ufstat & info->tx_fifomask) != 0 ||
 805                     (ufstat & info->tx_fifofull))
 806                         return 0;
 807
 808                 return 1;
 809         }
 810
 811         return s3c24xx_serial_txempty_nofifo(port);
 812 }
 813
 814 /* no modem control lines */
 815 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
 816 {
 817         unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
 818
 819         if (umstat & S3C2410_UMSTAT_CTS)
 820                 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 821         else
 822                 return TIOCM_CAR | TIOCM_DSR;
 823 }
 824
 825 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
 826 {
 827         unsigned int umcon = rd_regl(port, S3C2410_UMCON);
 828
 829         if (mctrl & TIOCM_RTS)
 830                 umcon |= S3C2410_UMCOM_RTS_LOW;
 831         else
 832                 umcon &= ~S3C2410_UMCOM_RTS_LOW;
 833
 834         wr_regl(port, S3C2410_UMCON, umcon);
 835 }
 836
 837 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
 838 {
 839         unsigned long flags;
 840         unsigned int ucon;
 841
 842         spin_lock_irqsave(&port->lock, flags);
 843
 844         ucon = rd_regl(port, S3C2410_UCON);
 845
 846         if (break_state)
 847                 ucon |= S3C2410_UCON_SBREAK;
 848         else
 849                 ucon &= ~S3C2410_UCON_SBREAK;
 850
 851         wr_regl(port, S3C2410_UCON, ucon);
 852
 853         spin_unlock_irqrestore(&port->lock, flags);
 854 }
 855
 856 static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
 857 {
 858         struct s3c24xx_uart_dma *dma = p->dma;
 859         struct dma_slave_caps dma_caps;
 860         const char *reason = NULL;
 861         int ret;
 862
 863         /* Default slave configuration parameters */
 864         dma->rx_conf.direction          = DMA_DEV_TO_MEM;
 865         dma->rx_conf.src_addr_width     = DMA_SLAVE_BUSWIDTH_1_BYTE;
 866         dma->rx_conf.src_addr           = p->port.mapbase + S3C2410_URXH;
 867         dma->rx_conf.src_maxburst       = 1;
 868
 869         dma->tx_conf.direction          = DMA_MEM_TO_DEV;
 870         dma->tx_conf.dst_addr_width     = DMA_SLAVE_BUSWIDTH_1_BYTE;
 871         dma->tx_conf.dst_addr           = p->port.mapbase + S3C2410_UTXH;
 872         dma->tx_conf.dst_maxburst       = 1;
 873
 874         dma->rx_chan = dma_request_chan(p->port.dev, "rx");
 875
 876         if (IS_ERR(dma->rx_chan)) {
 877                 reason = "DMA RX channel request failed";
 878                 ret = PTR_ERR(dma->rx_chan);
 879                 goto err_warn;
 880         }
 881
 882         ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);
 883         if (ret < 0 ||
 884             dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
 885                 reason = "insufficient DMA RX engine capabilities";
 886                 ret = -EOPNOTSUPP;
 887                 goto err_release_rx;
 888         }
 889
 890         dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
 891
 892         dma->tx_chan = dma_request_chan(p->port.dev, "tx");
 893         if (IS_ERR(dma->tx_chan)) {
 894                 reason = "DMA TX channel request failed";
 895                 ret = PTR_ERR(dma->tx_chan);
 896                 goto err_release_rx;
 897         }
 898
 899         ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);
 900         if (ret < 0 ||
 901             dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
 902                 reason = "insufficient DMA TX engine capabilities";
 903                 ret = -EOPNOTSUPP;
 904                 goto err_release_tx;
 905         }
 906
 907         dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
 908
 909         /* RX buffer */
 910         dma->rx_size = PAGE_SIZE;
 911
 912         dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
 913         if (!dma->rx_buf) {
 914                 ret = -ENOMEM;
 915                 goto err_release_tx;
 916         }
 917
 918         dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf,
 919                                 dma->rx_size, DMA_FROM_DEVICE);
 920         if (dma_mapping_error(p->port.dev, dma->rx_addr)) {
 921                 reason = "DMA mapping error for RX buffer";
 922                 ret = -EIO;
 923                 goto err_free_rx;
 924         }
 925
 926         /* TX buffer */
 927         dma->tx_addr = dma_map_single(p->port.dev, p->port.state->xmit.buf,
 928                                 UART_XMIT_SIZE, DMA_TO_DEVICE);
 929         if (dma_mapping_error(p->port.dev, dma->tx_addr)) {
 930                 reason = "DMA mapping error for TX buffer";
 931                 ret = -EIO;
 932                 goto err_unmap_rx;
 933         }
 934
 935         return 0;
 936
 937 err_unmap_rx:
 938         dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size,
 939                          DMA_FROM_DEVICE);
 940 err_free_rx:
 941         kfree(dma->rx_buf);
 942 err_release_tx:
 943         dma_release_channel(dma->tx_chan);
 944 err_release_rx:
 945         dma_release_channel(dma->rx_chan);
 946 err_warn:
 947         if (reason)
 948                 dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
 949         return ret;
 950 }
 951
 952 static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
 953 {
 954         struct s3c24xx_uart_dma *dma = p->dma;
 955
 956         if (dma->rx_chan) {
 957                 dmaengine_terminate_all(dma->rx_chan);
 958                 dma_unmap_single(p->port.dev, dma->rx_addr,
 959                                 dma->rx_size, DMA_FROM_DEVICE);
 960                 kfree(dma->rx_buf);
 961                 dma_release_channel(dma->rx_chan);
 962                 dma->rx_chan = NULL;
 963         }
 964
 965         if (dma->tx_chan) {
 966                 dmaengine_terminate_all(dma->tx_chan);
 967                 dma_unmap_single(p->port.dev, dma->tx_addr,
 968                                 UART_XMIT_SIZE, DMA_TO_DEVICE);
 969                 dma_release_channel(dma->tx_chan);
 970                 dma->tx_chan = NULL;
 971         }
 972 }
 973
 974 static void s3c24xx_serial_shutdown(struct uart_port *port)
 975 {
 976         struct s3c24xx_uart_port *ourport = to_ourport(port);
 977
 978         if (ourport->tx_claimed) {
 979                 if (!s3c24xx_serial_has_interrupt_mask(port))
 980                         free_irq(ourport->tx_irq, ourport);
 981                 tx_enabled(port) = 0;
 982                 ourport->tx_claimed = 0;
 983                 ourport->tx_mode = 0;
 984         }
 985
 986         if (ourport->rx_claimed) {
 987                 if (!s3c24xx_serial_has_interrupt_mask(port))
 988                         free_irq(ourport->rx_irq, ourport);
 989                 ourport->rx_claimed = 0;
 990                 rx_enabled(port) = 0;
 991         }
 992
 993         /* Clear pending interrupts and mask all interrupts */
 994         if (s3c24xx_serial_has_interrupt_mask(port)) {
 995                 free_irq(port->irq, ourport);
 996
 997                 wr_regl(port, S3C64XX_UINTP, 0xf);
 998                 wr_regl(port, S3C64XX_UINTM, 0xf);
 999         }
1000
1001         if (ourport->dma)
1002                 s3c24xx_serial_release_dma(ourport);
1003
1004         ourport->tx_in_progress = 0;
1005 }
1006
1007 static int s3c24xx_serial_startup(struct uart_port *port)
1008 {
1009         struct s3c24xx_uart_port *ourport = to_ourport(port);
1010         int ret;
1011
1012         dbg("s3c24xx_serial_startup: port=%p (%08llx,%p)\n",
1013             port, (unsigned long long)port->mapbase, port->membase);
1014
1015         rx_enabled(port) = 1;
1016
1017         ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0,
1018                           s3c24xx_serial_portname(port), ourport);
1019
1020         if (ret != 0) {
1021                 dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq);
1022                 return ret;
1023         }
1024
1025         ourport->rx_claimed = 1;
1026
1027         dbg("requesting tx irq...\n");
1028
1029         tx_enabled(port) = 1;
1030
1031         ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0,
1032                           s3c24xx_serial_portname(port), ourport);
1033
1034         if (ret) {
1035                 dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq);
1036                 goto err;
1037         }
1038
1039         ourport->tx_claimed = 1;
1040
1041         dbg("s3c24xx_serial_startup ok\n");
1042
1043         /* the port reset code should have done the correct
1044          * register setup for the port controls */
1045
1046         return ret;
1047
1048 err:
1049         s3c24xx_serial_shutdown(port);
1050         return ret;
1051 }
1052
1053 static int s3c64xx_serial_startup(struct uart_port *port)
1054 {
1055         struct s3c24xx_uart_port *ourport = to_ourport(port);
1056         unsigned long flags;
1057         unsigned int ufcon;
1058         int ret;
1059
1060         dbg("s3c64xx_serial_startup: port=%p (%08llx,%p)\n",
1061             port, (unsigned long long)port->mapbase, port->membase);
1062
1063         wr_regl(port, S3C64XX_UINTM, 0xf);
1064         if (ourport->dma) {
1065                 ret = s3c24xx_serial_request_dma(ourport);
1066                 if (ret < 0) {
1067                         devm_kfree(port->dev, ourport->dma);
1068                         ourport->dma = NULL;
1069                 }
1070         }
1071
1072         ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
1073                           s3c24xx_serial_portname(port), ourport);
1074         if (ret) {
1075                 dev_err(port->dev, "cannot get irq %d\n", port->irq);
1076                 return ret;
1077         }
1078
1079         /* For compatibility with s3c24xx Soc's */
1080         rx_enabled(port) = 1;
1081         ourport->rx_claimed = 1;
1082         tx_enabled(port) = 0;
1083         ourport->tx_claimed = 1;
1084
1085         spin_lock_irqsave(&port->lock, flags);
1086
1087         ufcon = rd_regl(port, S3C2410_UFCON);
1088         ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
1089         if (!uart_console(port))
1090                 ufcon |= S3C2410_UFCON_RESETTX;
1091         wr_regl(port, S3C2410_UFCON, ufcon);
1092
1093         enable_rx_pio(ourport);
1094
1095         spin_unlock_irqrestore(&port->lock, flags);
1096
1097         /* Enable Rx Interrupt */
1098         s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
1099
1100         dbg("s3c64xx_serial_startup ok\n");
1101         return ret;
1102 }
1103
1104 /* power power management control */
1105
1106 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
1107                               unsigned int old)
1108 {
1109         struct s3c24xx_uart_port *ourport = to_ourport(port);
1110         int timeout = 10000;
1111
1112         ourport->pm_level = level;
1113
1114         switch (level) {
1115         case 3:
1116                 while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
1117                         udelay(100);
1118
1119                 if (!IS_ERR(ourport->baudclk))
1120                         clk_disable_unprepare(ourport->baudclk);
1121
1122                 clk_disable_unprepare(ourport->clk);
1123                 break;
1124
1125         case 0:
1126                 clk_prepare_enable(ourport->clk);
1127
1128                 if (!IS_ERR(ourport->baudclk))
1129                         clk_prepare_enable(ourport->baudclk);
1130
1131                 break;
1132         default:
1133                 dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
1134         }
1135 }
1136
1137 /* baud rate calculation
1138  *
1139  * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
1140  * of different sources, including the peripheral clock ("pclk") and an
1141  * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
1142  * with a programmable extra divisor.
1143  *
1144  * The following code goes through the clock sources, and calculates the
1145  * baud clocks (and the resultant actual baud rates) and then tries to
1146  * pick the closest one and select that.
1147  *
1148 */
1149
1150 #define MAX_CLK_NAME_LENGTH 15
1151
1152 static inline int s3c24xx_serial_getsource(struct uart_port *port)
1153 {
1154         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1155         unsigned int ucon;
1156
1157         if (info->num_clks == 1)
1158                 return 0;
1159
1160         ucon = rd_regl(port, S3C2410_UCON);
1161         ucon &= info->clksel_mask;
1162         return ucon >> info->clksel_shift;
1163 }
1164
1165 static void s3c24xx_serial_setsource(struct uart_port *port,
1166                         unsigned int clk_sel)
1167 {
1168         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1169         unsigned int ucon;
1170
1171         if (info->num_clks == 1)
1172                 return;
1173
1174         ucon = rd_regl(port, S3C2410_UCON);
1175         if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)
1176                 return;
1177
1178         ucon &= ~info->clksel_mask;
1179         ucon |= clk_sel << info->clksel_shift;
1180         wr_regl(port, S3C2410_UCON, ucon);
1181 }
1182
1183 static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
1184                         unsigned int req_baud, struct clk **best_clk,
1185                         unsigned int *clk_num)
1186 {
1187         struct s3c24xx_uart_info *info = ourport->info;
1188         struct clk *clk;
1189         unsigned long rate;
1190         unsigned int cnt, baud, quot, clk_sel, best_quot = 0;
1191         char clkname[MAX_CLK_NAME_LENGTH];
1192         int calc_deviation, deviation = (1 << 30) - 1;
1193
1194         clk_sel = (ourport->cfg->clk_sel) ? ourport->cfg->clk_sel :
1195                         ourport->info->def_clk_sel;
1196         for (cnt = 0; cnt < info->num_clks; cnt++) {
1197                 if (!(clk_sel & (1 << cnt)))
1198                         continue;
1199
1200                 sprintf(clkname, "clk_uart_baud%d", cnt);
1201                 clk = clk_get(ourport->port.dev, clkname);
1202                 if (IS_ERR(clk))
1203                         continue;
1204
1205                 rate = clk_get_rate(clk);
1206                 if (!rate)
1207                         continue;
1208
1209                 if (ourport->info->has_divslot) {
1210                         unsigned long div = rate / req_baud;
1211
1212                         /* The UDIVSLOT register on the newer UARTs allows us to
1213                          * get a divisor adjustment of 1/16th on the baud clock.
1214                          *
1215                          * We don't keep the UDIVSLOT value (the 16ths we
1216                          * calculated by not multiplying the baud by 16) as it
1217                          * is easy enough to recalculate.
1218                          */
1219
1220                         quot = div / 16;
1221                         baud = rate / div;
1222                 } else {
1223                         quot = (rate + (8 * req_baud)) / (16 * req_baud);
1224                         baud = rate / (quot * 16);
1225                 }
1226                 quot--;
1227
1228                 calc_deviation = req_baud - baud;
1229                 if (calc_deviation < 0)
1230                         calc_deviation = -calc_deviation;
1231
1232                 if (calc_deviation < deviation) {
1233                         *best_clk = clk;
1234                         best_quot = quot;
1235                         *clk_num = cnt;
1236                         deviation = calc_deviation;
1237                 }
1238         }
1239
1240         return best_quot;
1241 }
1242
1243 /* udivslot_table[]
1244  *
1245  * This table takes the fractional value of the baud divisor and gives
1246  * the recommended setting for the UDIVSLOT register.
1247  */
1248 static u16 udivslot_table[16] = {
1249         [0] = 0x0000,
1250         [1] = 0x0080,
1251         [2] = 0x0808,
1252         [3] = 0x0888,
1253         [4] = 0x2222,
1254         [5] = 0x4924,
1255         [6] = 0x4A52,
1256         [7] = 0x54AA,
1257         [8] = 0x5555,
1258         [9] = 0xD555,
1259         [10] = 0xD5D5,
1260         [11] = 0xDDD5,
1261         [12] = 0xDDDD,
1262         [13] = 0xDFDD,
1263         [14] = 0xDFDF,
1264         [15] = 0xFFDF,
1265 };
1266
1267 static void s3c24xx_serial_set_termios(struct uart_port *port,
1268                                        struct ktermios *termios,
1269                                        struct ktermios *old)
1270 {
1271         struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
1272         struct s3c24xx_uart_port *ourport = to_ourport(port);
1273         struct clk *clk = ERR_PTR(-EINVAL);
1274         unsigned long flags;
1275         unsigned int baud, quot, clk_sel = 0;
1276         unsigned int ulcon;
1277         unsigned int umcon;
1278         unsigned int udivslot = 0;
1279
1280         /*
1281          * We don't support modem control lines.
1282          */
1283         termios->c_cflag &= ~(HUPCL | CMSPAR);
1284         termios->c_cflag |= CLOCAL;
1285
1286         /*
1287          * Ask the core to calculate the divisor for us.
1288          */
1289
1290         baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
1291         quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
1292         if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
1293                 quot = port->custom_divisor;
1294         if (IS_ERR(clk))
1295                 return;
1296
1297         /* check to see if we need  to change clock source */
1298
1299         if (ourport->baudclk != clk) {
1300                 clk_prepare_enable(clk);
1301
1302                 s3c24xx_serial_setsource(port, clk_sel);
1303
1304                 if (!IS_ERR(ourport->baudclk)) {
1305                         clk_disable_unprepare(ourport->baudclk);
1306                         ourport->baudclk = ERR_PTR(-EINVAL);
1307                 }
1308
1309                 ourport->baudclk = clk;
1310                 ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
1311         }
1312
1313         if (ourport->info->has_divslot) {
1314                 unsigned int div = ourport->baudclk_rate / baud;
1315
1316                 if (cfg->has_fracval) {
1317                         udivslot = (div & 15);
1318                         dbg("fracval = %04x\n", udivslot);
1319                 } else {
1320                         udivslot = udivslot_table[div & 15];
1321                         dbg("udivslot = %04x (div %d)\n", udivslot, div & 15);
1322                 }
1323         }
1324
1325         switch (termios->c_cflag & CSIZE) {
1326         case CS5:
1327                 dbg("config: 5bits/char\n");
1328                 ulcon = S3C2410_LCON_CS5;
1329                 break;
1330         case CS6:
1331                 dbg("config: 6bits/char\n");
1332                 ulcon = S3C2410_LCON_CS6;
1333                 break;
1334         case CS7:
1335                 dbg("config: 7bits/char\n");
1336                 ulcon = S3C2410_LCON_CS7;
1337                 break;
1338         case CS8:
1339         default:
1340                 dbg("config: 8bits/char\n");
1341                 ulcon = S3C2410_LCON_CS8;
1342                 break;
1343         }
1344
1345         /* preserve original lcon IR settings */
1346         ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
1347
1348         if (termios->c_cflag & CSTOPB)
1349                 ulcon |= S3C2410_LCON_STOPB;
1350
1351         if (termios->c_cflag & PARENB) {
1352                 if (termios->c_cflag & PARODD)
1353                         ulcon |= S3C2410_LCON_PODD;
1354                 else
1355                         ulcon |= S3C2410_LCON_PEVEN;
1356         } else {
1357                 ulcon |= S3C2410_LCON_PNONE;
1358         }
1359
1360         spin_lock_irqsave(&port->lock, flags);
1361
1362         dbg("setting ulcon to %08x, brddiv to %d, udivslot %08x\n",
1363             ulcon, quot, udivslot);
1364
1365         wr_regl(port, S3C2410_ULCON, ulcon);
1366         wr_regl(port, S3C2410_UBRDIV, quot);
1367
1368         umcon = rd_regl(port, S3C2410_UMCON);
1369         if (termios->c_cflag & CRTSCTS) {
1370                 umcon |= S3C2410_UMCOM_AFC;
1371                 /* Disable RTS when RX FIFO contains 63 bytes */
1372                 umcon &= ~S3C2412_UMCON_AFC_8;
1373         } else {
1374                 umcon &= ~S3C2410_UMCOM_AFC;
1375         }
1376         wr_regl(port, S3C2410_UMCON, umcon);
1377
1378         if (ourport->info->has_divslot)
1379                 wr_regl(port, S3C2443_DIVSLOT, udivslot);
1380
1381         dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
1382             rd_regl(port, S3C2410_ULCON),
1383             rd_regl(port, S3C2410_UCON),
1384             rd_regl(port, S3C2410_UFCON));
1385
1386         /*
1387          * Update the per-port timeout.
1388          */
1389         uart_update_timeout(port, termios->c_cflag, baud);
1390
1391         /*
1392          * Which character status flags are we interested in?
1393          */
1394         port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
1395         if (termios->c_iflag & INPCK)
1396                 port->read_status_mask |= S3C2410_UERSTAT_FRAME |
1397                         S3C2410_UERSTAT_PARITY;
1398         /*
1399          * Which character status flags should we ignore?
1400          */
1401         port->ignore_status_mask = 0;
1402         if (termios->c_iflag & IGNPAR)
1403                 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
1404         if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
1405                 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
1406
1407         /*
1408          * Ignore all characters if CREAD is not set.
1409          */
1410         if ((termios->c_cflag & CREAD) == 0)
1411                 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
1412
1413         spin_unlock_irqrestore(&port->lock, flags);
1414 }
1415
1416 static const char *s3c24xx_serial_type(struct uart_port *port)
1417 {
1418         switch (port->type) {
1419         case PORT_S3C2410:
1420                 return "S3C2410";
1421         case PORT_S3C2440:
1422                 return "S3C2440";
1423         case PORT_S3C2412:
1424                 return "S3C2412";
1425         case PORT_S3C6400:
1426                 return "S3C6400/10";
1427         default:
1428                 return NULL;
1429         }
1430 }
1431
1432 #define MAP_SIZE (0x100)
1433
1434 static void s3c24xx_serial_release_port(struct uart_port *port)
1435 {
1436         release_mem_region(port->mapbase, MAP_SIZE);
1437 }
1438
1439 static int s3c24xx_serial_request_port(struct uart_port *port)
1440 {
1441         const char *name = s3c24xx_serial_portname(port);
1442         return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
1443 }
1444
1445 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
1446 {
1447         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1448
1449         if (flags & UART_CONFIG_TYPE &&
1450             s3c24xx_serial_request_port(port) == 0)
1451                 port->type = info->type;
1452 }
1453
1454 /*
1455  * verify the new serial_struct (for TIOCSSERIAL).
1456  */
1457 static int
1458 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
1459 {
1460         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1461
1462         if (ser->type != PORT_UNKNOWN && ser->type != info->type)
1463                 return -EINVAL;
1464
1465         return 0;
1466 }
1467
1468
1469 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1470
1471 static struct console s3c24xx_serial_console;
1472
1473 static int __init s3c24xx_serial_console_init(void)
1474 {
1475         register_console(&s3c24xx_serial_console);
1476         return 0;
1477 }
1478 console_initcall(s3c24xx_serial_console_init);
1479
1480 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
1481 #else
1482 #define S3C24XX_SERIAL_CONSOLE NULL
1483 #endif
1484
1485 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1486 static int s3c24xx_serial_get_poll_char(struct uart_port *port);
1487 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1488                          unsigned char c);
1489 #endif
1490
1491 static struct uart_ops s3c24xx_serial_ops = {
1492         .pm             = s3c24xx_serial_pm,
1493         .tx_empty       = s3c24xx_serial_tx_empty,
1494         .get_mctrl      = s3c24xx_serial_get_mctrl,
1495         .set_mctrl      = s3c24xx_serial_set_mctrl,
1496         .stop_tx        = s3c24xx_serial_stop_tx,
1497         .start_tx       = s3c24xx_serial_start_tx,
1498         .stop_rx        = s3c24xx_serial_stop_rx,
1499         .break_ctl      = s3c24xx_serial_break_ctl,
1500         .startup        = s3c24xx_serial_startup,
1501         .shutdown       = s3c24xx_serial_shutdown,
1502         .set_termios    = s3c24xx_serial_set_termios,
1503         .type           = s3c24xx_serial_type,
1504         .release_port   = s3c24xx_serial_release_port,
1505         .request_port   = s3c24xx_serial_request_port,
1506         .config_port    = s3c24xx_serial_config_port,
1507         .verify_port    = s3c24xx_serial_verify_port,
1508 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1509         .poll_get_char = s3c24xx_serial_get_poll_char,
1510         .poll_put_char = s3c24xx_serial_put_poll_char,
1511 #endif
1512 };
1513
1514 static struct uart_driver s3c24xx_uart_drv = {
1515         .owner          = THIS_MODULE,
1516         .driver_name    = "s3c2410_serial",
1517         .nr             = CONFIG_SERIAL_SAMSUNG_UARTS,
1518         .cons           = S3C24XX_SERIAL_CONSOLE,
1519         .dev_name       = S3C24XX_SERIAL_NAME,
1520         .major          = S3C24XX_SERIAL_MAJOR,
1521         .minor          = S3C24XX_SERIAL_MINOR,
1522 };
1523
1524 #define __PORT_LOCK_UNLOCKED(i) \
1525         __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[i].port.lock)
1526 static struct s3c24xx_uart_port
1527 s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
1528         [0] = {
1529                 .port = {
1530                         .lock           = __PORT_LOCK_UNLOCKED(0),
1531                         .iotype         = UPIO_MEM,
1532                         .uartclk        = 0,
1533                         .fifosize       = 16,
1534                         .ops            = &s3c24xx_serial_ops,
1535                         .flags          = UPF_BOOT_AUTOCONF,
1536                         .line           = 0,
1537                 }
1538         },
1539         [1] = {
1540                 .port = {
1541                         .lock           = __PORT_LOCK_UNLOCKED(1),
1542                         .iotype         = UPIO_MEM,
1543                         .uartclk        = 0,
1544                         .fifosize       = 16,
1545                         .ops            = &s3c24xx_serial_ops,
1546                         .flags          = UPF_BOOT_AUTOCONF,
1547                         .line           = 1,
1548                 }
1549         },
1550 #if CONFIG_SERIAL_SAMSUNG_UARTS > 2
1551
1552         [2] = {
1553                 .port = {
1554                         .lock           = __PORT_LOCK_UNLOCKED(2),
1555                         .iotype         = UPIO_MEM,
1556                         .uartclk        = 0,
1557                         .fifosize       = 16,
1558                         .ops            = &s3c24xx_serial_ops,
1559                         .flags          = UPF_BOOT_AUTOCONF,
1560                         .line           = 2,
1561                 }
1562         },
1563 #endif
1564 #if CONFIG_SERIAL_SAMSUNG_UARTS > 3
1565         [3] = {
1566                 .port = {
1567                         .lock           = __PORT_LOCK_UNLOCKED(3),
1568                         .iotype         = UPIO_MEM,
1569                         .uartclk        = 0,
1570                         .fifosize       = 16,
1571                         .ops            = &s3c24xx_serial_ops,
1572                         .flags          = UPF_BOOT_AUTOCONF,
1573                         .line           = 3,
1574                 }
1575         }
1576 #endif
1577 };
1578 #undef __PORT_LOCK_UNLOCKED
1579
1580 /* s3c24xx_serial_resetport
1581  *
1582  * reset the fifos and other the settings.
1583 */
1584
1585 static void s3c24xx_serial_resetport(struct uart_port *port,
1586                                    struct s3c2410_uartcfg *cfg)
1587 {
1588         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1589         unsigned long ucon = rd_regl(port, S3C2410_UCON);
1590         unsigned int ucon_mask;
1591
1592         ucon_mask = info->clksel_mask;
1593         if (info->type == PORT_S3C2440)
1594                 ucon_mask |= S3C2440_UCON0_DIVMASK;
1595
1596         ucon &= ucon_mask;
1597         wr_regl(port, S3C2410_UCON,  ucon | cfg->ucon);
1598
1599         /* reset both fifos */
1600         wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
1601         wr_regl(port, S3C2410_UFCON, cfg->ufcon);
1602
1603         /* some delay is required after fifo reset */
1604         udelay(1);
1605 }
1606
1607
1608 #ifdef CONFIG_ARM_S3C24XX_CPUFREQ
1609
1610 static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb,
1611                                              unsigned long val, void *data)
1612 {
1613         struct s3c24xx_uart_port *port;
1614         struct uart_port *uport;
1615
1616         port = container_of(nb, struct s3c24xx_uart_port, freq_transition);
1617         uport = &port->port;
1618
1619         /* check to see if port is enabled */
1620
1621         if (port->pm_level != 0)
1622                 return 0;
1623
1624         /* try and work out if the baudrate is changing, we can detect
1625          * a change in rate, but we do not have support for detecting
1626          * a disturbance in the clock-rate over the change.
1627          */
1628
1629         if (IS_ERR(port->baudclk))
1630                 goto exit;
1631
1632         if (port->baudclk_rate == clk_get_rate(port->baudclk))
1633                 goto exit;
1634
1635         if (val == CPUFREQ_PRECHANGE) {
1636                 /* we should really shut the port down whilst the
1637                  * frequency change is in progress. */
1638
1639         } else if (val == CPUFREQ_POSTCHANGE) {
1640                 struct ktermios *termios;
1641                 struct tty_struct *tty;
1642
1643                 if (uport->state == NULL)
1644                         goto exit;
1645
1646                 tty = uport->state->port.tty;
1647
1648                 if (tty == NULL)
1649                         goto exit;
1650
1651                 termios = &tty->termios;
1652
1653                 if (termios == NULL) {
1654                         dev_warn(uport->dev, "%s: no termios?\n", __func__);
1655                         goto exit;
1656                 }
1657
1658                 s3c24xx_serial_set_termios(uport, termios, NULL);
1659         }
1660
1661 exit:
1662         return 0;
1663 }
1664
1665 static inline int
1666 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1667 {
1668         port->freq_transition.notifier_call = s3c24xx_serial_cpufreq_transition;
1669
1670         return cpufreq_register_notifier(&port->freq_transition,
1671                                          CPUFREQ_TRANSITION_NOTIFIER);
1672 }
1673
1674 static inline void
1675 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1676 {
1677         cpufreq_unregister_notifier(&port->freq_transition,
1678                                     CPUFREQ_TRANSITION_NOTIFIER);
1679 }
1680
1681 #else
1682 static inline int
1683 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1684 {
1685         return 0;
1686 }
1687
1688 static inline void
1689 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1690 {
1691 }
1692 #endif
1693
1694 /* s3c24xx_serial_init_port
1695  *
1696  * initialise a single serial port from the platform device given
1697  */
1698
1699 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
1700                                     struct platform_device *platdev)
1701 {
1702         struct uart_port *port = &ourport->port;
1703         struct s3c2410_uartcfg *cfg = ourport->cfg;
1704         struct resource *res;
1705         int ret;
1706
1707         dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
1708
1709         if (platdev == NULL)
1710                 return -ENODEV;
1711
1712         if (port->mapbase != 0)
1713                 return -EINVAL;
1714
1715         /* setup info for port */
1716         port->dev       = &platdev->dev;
1717
1718         /* Startup sequence is different for s3c64xx and higher SoC's */
1719         if (s3c24xx_serial_has_interrupt_mask(port))
1720                 s3c24xx_serial_ops.startup = s3c64xx_serial_startup;
1721
1722         port->uartclk = 1;
1723
1724         if (cfg->uart_flags & UPF_CONS_FLOW) {
1725                 dbg("s3c24xx_serial_init_port: enabling flow control\n");
1726                 port->flags |= UPF_CONS_FLOW;
1727         }
1728
1729         /* sort our the physical and virtual addresses for each UART */
1730
1731         res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1732         if (res == NULL) {
1733                 dev_err(port->dev, "failed to find memory resource for uart\n");
1734                 return -EINVAL;
1735         }
1736
1737         dbg("resource %pR)\n", res);
1738
1739         port->membase = devm_ioremap(port->dev, res->start, resource_size(res));
1740         if (!port->membase) {
1741                 dev_err(port->dev, "failed to remap controller address\n");
1742                 return -EBUSY;
1743         }
1744
1745         port->mapbase = res->start;
1746         ret = platform_get_irq(platdev, 0);
1747         if (ret < 0)
1748                 port->irq = 0;
1749         else {
1750                 port->irq = ret;
1751                 ourport->rx_irq = ret;
1752                 ourport->tx_irq = ret + 1;
1753         }
1754
1755         ret = platform_get_irq(platdev, 1);
1756         if (ret > 0)
1757                 ourport->tx_irq = ret;
1758         /*
1759          * DMA is currently supported only on DT platforms, if DMA properties
1760          * are specified.
1761          */
1762         if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,
1763                                                      "dmas", NULL)) {
1764                 ourport->dma = devm_kzalloc(port->dev,
1765                                             sizeof(*ourport->dma),
1766                                             GFP_KERNEL);
1767                 if (!ourport->dma) {
1768                         ret = -ENOMEM;
1769                         goto err;
1770                 }
1771         }
1772
1773         ourport->clk    = clk_get(&platdev->dev, "uart");
1774         if (IS_ERR(ourport->clk)) {
1775                 pr_err("%s: Controller clock not found\n",
1776                                 dev_name(&platdev->dev));
1777                 ret = PTR_ERR(ourport->clk);
1778                 goto err;
1779         }
1780
1781         ret = clk_prepare_enable(ourport->clk);
1782         if (ret) {
1783                 pr_err("uart: clock failed to prepare+enable: %d\n", ret);
1784                 clk_put(ourport->clk);
1785                 goto err;
1786         }
1787
1788         /* Keep all interrupts masked and cleared */
1789         if (s3c24xx_serial_has_interrupt_mask(port)) {
1790                 wr_regl(port, S3C64XX_UINTM, 0xf);
1791                 wr_regl(port, S3C64XX_UINTP, 0xf);
1792                 wr_regl(port, S3C64XX_UINTSP, 0xf);
1793         }
1794
1795         dbg("port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",
1796             &port->mapbase, port->membase, port->irq,
1797             ourport->rx_irq, ourport->tx_irq, port->uartclk);
1798
1799         /* reset the fifos (and setup the uart) */
1800         s3c24xx_serial_resetport(port, cfg);
1801
1802         return 0;
1803
1804 err:
1805         port->mapbase = 0;
1806         return ret;
1807 }
1808
1809 /* Device driver serial port probe */
1810
1811 static const struct of_device_id s3c24xx_uart_dt_match[];
1812 static int probe_index;
1813
1814 static inline struct s3c24xx_serial_drv_data *s3c24xx_get_driver_data(
1815                         struct platform_device *pdev)
1816 {
1817 #ifdef CONFIG_OF
1818         if (pdev->dev.of_node) {
1819                 const struct of_device_id *match;
1820                 match = of_match_node(s3c24xx_uart_dt_match, pdev->dev.of_node);
1821                 return (struct s3c24xx_serial_drv_data *)match->data;
1822         }
1823 #endif
1824         return (struct s3c24xx_serial_drv_data *)
1825                         platform_get_device_id(pdev)->driver_data;
1826 }
1827
1828 static int s3c24xx_serial_probe(struct platform_device *pdev)
1829 {
1830         struct device_node *np = pdev->dev.of_node;
1831         struct s3c24xx_uart_port *ourport;
1832         int index = probe_index;
1833         int ret;
1834
1835         if (np) {
1836                 ret = of_alias_get_id(np, "serial");
1837                 if (ret >= 0)
1838                         index = ret;
1839         }
1840
1841         dbg("s3c24xx_serial_probe(%p) %d\n", pdev, index);
1842
1843         if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) {
1844                 dev_err(&pdev->dev, "serial%d out of range\n", index);
1845                 return -EINVAL;
1846         }
1847         ourport = &s3c24xx_serial_ports[index];
1848
1849         ourport->drv_data = s3c24xx_get_driver_data(pdev);
1850         if (!ourport->drv_data) {
1851                 dev_err(&pdev->dev, "could not find driver data\n");
1852                 return -ENODEV;
1853         }
1854
1855         ourport->baudclk = ERR_PTR(-EINVAL);
1856         ourport->info = ourport->drv_data->info;
1857         ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
1858                         dev_get_platdata(&pdev->dev) :
1859                         ourport->drv_data->def_cfg;
1860
1861         if (np)
1862                 of_property_read_u32(np,
1863                         "samsung,uart-fifosize", &ourport->port.fifosize);
1864
1865         if (ourport->drv_data->fifosize[index])
1866                 ourport->port.fifosize = ourport->drv_data->fifosize[index];
1867         else if (ourport->info->fifosize)
1868                 ourport->port.fifosize = ourport->info->fifosize;
1869
1870         /*
1871          * DMA transfers must be aligned at least to cache line size,
1872          * so find minimal transfer size suitable for DMA mode
1873          */
1874         ourport->min_dma_size = max_t(int, ourport->port.fifosize,
1875                                     dma_get_cache_alignment());
1876
1877         dbg("%s: initialising port %p...\n", __func__, ourport);
1878
1879         ret = s3c24xx_serial_init_port(ourport, pdev);
1880         if (ret < 0)
1881                 return ret;
1882
1883         if (!s3c24xx_uart_drv.state) {
1884                 ret = uart_register_driver(&s3c24xx_uart_drv);
1885                 if (ret < 0) {
1886                         pr_err("Failed to register Samsung UART driver\n");
1887                         return ret;
1888                 }
1889         }
1890
1891         dbg("%s: adding port\n", __func__);
1892         uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
1893         platform_set_drvdata(pdev, &ourport->port);
1894
1895         /*
1896          * Deactivate the clock enabled in s3c24xx_serial_init_port here,
1897          * so that a potential re-enablement through the pm-callback overlaps
1898          * and keeps the clock enabled in this case.
1899          */
1900         clk_disable_unprepare(ourport->clk);
1901
1902         ret = s3c24xx_serial_cpufreq_register(ourport);
1903         if (ret < 0)
1904                 dev_err(&pdev->dev, "failed to add cpufreq notifier\n");
1905
1906         probe_index++;
1907
1908         return 0;
1909 }
1910
1911 static int s3c24xx_serial_remove(struct platform_device *dev)
1912 {
1913         struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1914
1915         if (port) {
1916                 s3c24xx_serial_cpufreq_deregister(to_ourport(port));
1917                 uart_remove_one_port(&s3c24xx_uart_drv, port);
1918         }
1919
1920         uart_unregister_driver(&s3c24xx_uart_drv);
1921
1922         return 0;
1923 }
1924
1925 /* UART power management code */
1926 #ifdef CONFIG_PM_SLEEP
1927 static int s3c24xx_serial_suspend(struct device *dev)
1928 {
1929         struct uart_port *port = s3c24xx_dev_to_port(dev);
1930
1931         if (port)
1932                 uart_suspend_port(&s3c24xx_uart_drv, port);
1933
1934         return 0;
1935 }
1936
1937 static int s3c24xx_serial_resume(struct device *dev)
1938 {
1939         struct uart_port *port = s3c24xx_dev_to_port(dev);
1940         struct s3c24xx_uart_port *ourport = to_ourport(port);
1941
1942         if (port) {
1943                 clk_prepare_enable(ourport->clk);
1944                 if (!IS_ERR(ourport->baudclk))
1945                         clk_prepare_enable(ourport->baudclk);
1946                 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1947                 if (!IS_ERR(ourport->baudclk))
1948                         clk_disable_unprepare(ourport->baudclk);
1949                 clk_disable_unprepare(ourport->clk);
1950
1951                 uart_resume_port(&s3c24xx_uart_drv, port);
1952         }
1953
1954         return 0;
1955 }
1956
1957 static int s3c24xx_serial_resume_noirq(struct device *dev)
1958 {
1959         struct uart_port *port = s3c24xx_dev_to_port(dev);
1960         struct s3c24xx_uart_port *ourport = to_ourport(port);
1961
1962         if (port) {
1963                 /* restore IRQ mask */
1964                 if (s3c24xx_serial_has_interrupt_mask(port)) {
1965                         unsigned int uintm = 0xf;
1966                         if (tx_enabled(port))
1967                                 uintm &= ~S3C64XX_UINTM_TXD_MSK;
1968                         if (rx_enabled(port))
1969                                 uintm &= ~S3C64XX_UINTM_RXD_MSK;
1970                         clk_prepare_enable(ourport->clk);
1971                         if (!IS_ERR(ourport->baudclk))
1972                                 clk_prepare_enable(ourport->baudclk);
1973                         wr_regl(port, S3C64XX_UINTM, uintm);
1974                         if (!IS_ERR(ourport->baudclk))
1975                                 clk_disable_unprepare(ourport->baudclk);
1976                         clk_disable_unprepare(ourport->clk);
1977                 }
1978         }
1979
1980         return 0;
1981 }
1982
1983 static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
1984         .suspend = s3c24xx_serial_suspend,
1985         .resume = s3c24xx_serial_resume,
1986         .resume_noirq = s3c24xx_serial_resume_noirq,
1987 };
1988 #define SERIAL_SAMSUNG_PM_OPS   (&s3c24xx_serial_pm_ops)
1989
1990 #else /* !CONFIG_PM_SLEEP */
1991
1992 #define SERIAL_SAMSUNG_PM_OPS   NULL
1993 #endif /* CONFIG_PM_SLEEP */
1994
1995 /* Console code */
1996
1997 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1998
1999 static struct uart_port *cons_uart;
2000
2001 static int
2002 s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
2003 {
2004         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
2005         unsigned long ufstat, utrstat;
2006
2007         if (ufcon & S3C2410_UFCON_FIFOMODE) {
2008                 /* fifo mode - check amount of data in fifo registers... */
2009
2010                 ufstat = rd_regl(port, S3C2410_UFSTAT);
2011                 return (ufstat & info->tx_fifofull) ? 0 : 1;
2012         }
2013
2014         /* in non-fifo mode, we go and use the tx buffer empty */
2015
2016         utrstat = rd_regl(port, S3C2410_UTRSTAT);
2017         return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
2018 }
2019
2020 static bool
2021 s3c24xx_port_configured(unsigned int ucon)
2022 {
2023         /* consider the serial port configured if the tx/rx mode set */
2024         return (ucon & 0xf) != 0;
2025 }
2026
2027 #ifdef CONFIG_CONSOLE_POLL
2028 /*
2029  * Console polling routines for writing and reading from the uart while
2030  * in an interrupt or debug context.
2031  */
2032
2033 static int s3c24xx_serial_get_poll_char(struct uart_port *port)
2034 {
2035         struct s3c24xx_uart_port *ourport = to_ourport(port);
2036         unsigned int ufstat;
2037
2038         ufstat = rd_regl(port, S3C2410_UFSTAT);
2039         if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
2040                 return NO_POLL_CHAR;
2041
2042         return rd_regb(port, S3C2410_URXH);
2043 }
2044
2045 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
2046                 unsigned char c)
2047 {
2048         unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2049         unsigned int ucon = rd_regl(port, S3C2410_UCON);
2050
2051         /* not possible to xmit on unconfigured port */
2052         if (!s3c24xx_port_configured(ucon))
2053                 return;
2054
2055         while (!s3c24xx_serial_console_txrdy(port, ufcon))
2056                 cpu_relax();
2057         wr_regb(port, S3C2410_UTXH, c);
2058 }
2059
2060 #endif /* CONFIG_CONSOLE_POLL */
2061
2062 static void
2063 s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
2064 {
2065         unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2066
2067         while (!s3c24xx_serial_console_txrdy(port, ufcon))
2068                 cpu_relax();
2069         wr_regb(port, S3C2410_UTXH, ch);
2070 }
2071
2072 static void
2073 s3c24xx_serial_console_write(struct console *co, const char *s,
2074                              unsigned int count)
2075 {
2076         unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
2077
2078         /* not possible to xmit on unconfigured port */
2079         if (!s3c24xx_port_configured(ucon))
2080                 return;
2081
2082         uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
2083 }
2084
2085 static void __init
2086 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
2087                            int *parity, int *bits)
2088 {
2089         struct clk *clk;
2090         unsigned int ulcon;
2091         unsigned int ucon;
2092         unsigned int ubrdiv;
2093         unsigned long rate;
2094         unsigned int clk_sel;
2095         char clk_name[MAX_CLK_NAME_LENGTH];
2096
2097         ulcon  = rd_regl(port, S3C2410_ULCON);
2098         ucon   = rd_regl(port, S3C2410_UCON);
2099         ubrdiv = rd_regl(port, S3C2410_UBRDIV);
2100
2101         dbg("s3c24xx_serial_get_options: port=%p\n"
2102             "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
2103             port, ulcon, ucon, ubrdiv);
2104
2105         if (s3c24xx_port_configured(ucon)) {
2106                 switch (ulcon & S3C2410_LCON_CSMASK) {
2107                 case S3C2410_LCON_CS5:
2108                         *bits = 5;
2109                         break;
2110                 case S3C2410_LCON_CS6:
2111                         *bits = 6;
2112                         break;
2113                 case S3C2410_LCON_CS7:
2114                         *bits = 7;
2115                         break;
2116                 case S3C2410_LCON_CS8:
2117                 default:
2118                         *bits = 8;
2119                         break;
2120                 }
2121
2122                 switch (ulcon & S3C2410_LCON_PMASK) {
2123                 case S3C2410_LCON_PEVEN:
2124                         *parity = 'e';
2125                         break;
2126
2127                 case S3C2410_LCON_PODD:
2128                         *parity = 'o';
2129                         break;
2130
2131                 case S3C2410_LCON_PNONE:
2132                 default:
2133                         *parity = 'n';
2134                 }
2135
2136                 /* now calculate the baud rate */
2137
2138                 clk_sel = s3c24xx_serial_getsource(port);
2139                 sprintf(clk_name, "clk_uart_baud%d", clk_sel);
2140
2141                 clk = clk_get(port->dev, clk_name);
2142                 if (!IS_ERR(clk))
2143                         rate = clk_get_rate(clk);
2144                 else
2145                         rate = 1;
2146
2147                 *baud = rate / (16 * (ubrdiv + 1));
2148                 dbg("calculated baud %d\n", *baud);
2149         }
2150
2151 }
2152
2153 static int __init
2154 s3c24xx_serial_console_setup(struct console *co, char *options)
2155 {
2156         struct uart_port *port;
2157         int baud = 9600;
2158         int bits = 8;
2159         int parity = 'n';
2160         int flow = 'n';
2161
2162         dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
2163             co, co->index, options);
2164
2165         /* is this a valid port */
2166
2167         if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
2168                 co->index = 0;
2169
2170         port = &s3c24xx_serial_ports[co->index].port;
2171
2172         /* is the port configured? */
2173
2174         if (port->mapbase == 0x0)
2175                 return -ENODEV;
2176
2177         cons_uart = port;
2178
2179         dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
2180
2181         /*
2182          * Check whether an invalid uart number has been specified, and
2183          * if so, search for the first available port that does have
2184          * console support.
2185          */
2186         if (options)
2187                 uart_parse_options(options, &baud, &parity, &bits, &flow);
2188         else
2189                 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
2190
2191         dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
2192
2193         return uart_set_options(port, co, baud, parity, bits, flow);
2194 }
2195
2196 static struct console s3c24xx_serial_console = {
2197         .name           = S3C24XX_SERIAL_NAME,
2198         .device         = uart_console_device,
2199         .flags          = CON_PRINTBUFFER,
2200         .index          = -1,
2201         .write          = s3c24xx_serial_console_write,
2202         .setup          = s3c24xx_serial_console_setup,
2203         .data           = &s3c24xx_uart_drv,
2204 };
2205 #endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
2206
2207 #ifdef CONFIG_CPU_S3C2410
2208 static struct s3c24xx_serial_drv_data s3c2410_serial_drv_data = {
2209         .info = &(struct s3c24xx_uart_info) {
2210                 .name           = "Samsung S3C2410 UART",
2211                 .type           = PORT_S3C2410,
2212                 .fifosize       = 16,
2213                 .rx_fifomask    = S3C2410_UFSTAT_RXMASK,
2214                 .rx_fifoshift   = S3C2410_UFSTAT_RXSHIFT,
2215                 .rx_fifofull    = S3C2410_UFSTAT_RXFULL,
2216                 .tx_fifofull    = S3C2410_UFSTAT_TXFULL,
2217                 .tx_fifomask    = S3C2410_UFSTAT_TXMASK,
2218                 .tx_fifoshift   = S3C2410_UFSTAT_TXSHIFT,
2219                 .def_clk_sel    = S3C2410_UCON_CLKSEL0,
2220                 .num_clks       = 2,
2221                 .clksel_mask    = S3C2410_UCON_CLKMASK,
2222                 .clksel_shift   = S3C2410_UCON_CLKSHIFT,
2223         },
2224         .def_cfg = &(struct s3c2410_uartcfg) {
2225                 .ucon           = S3C2410_UCON_DEFAULT,
2226                 .ufcon          = S3C2410_UFCON_DEFAULT,
2227         },
2228 };
2229 #define S3C2410_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2410_serial_drv_data)
2230 #else
2231 #define S3C2410_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2232 #endif
2233
2234 #ifdef CONFIG_CPU_S3C2412
2235 static struct s3c24xx_serial_drv_data s3c2412_serial_drv_data = {
2236         .info = &(struct s3c24xx_uart_info) {
2237                 .name           = "Samsung S3C2412 UART",
2238                 .type           = PORT_S3C2412,
2239                 .fifosize       = 64,
2240                 .has_divslot    = 1,
2241                 .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2242                 .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2243                 .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2244                 .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2245                 .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2246                 .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2247                 .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2248                 .num_clks       = 4,
2249                 .clksel_mask    = S3C2412_UCON_CLKMASK,
2250                 .clksel_shift   = S3C2412_UCON_CLKSHIFT,
2251         },
2252         .def_cfg = &(struct s3c2410_uartcfg) {
2253                 .ucon           = S3C2410_UCON_DEFAULT,
2254                 .ufcon          = S3C2410_UFCON_DEFAULT,
2255         },
2256 };
2257 #define S3C2412_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2412_serial_drv_data)
2258 #else
2259 #define S3C2412_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2260 #endif
2261
2262 #if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2416) || \
2263         defined(CONFIG_CPU_S3C2443) || defined(CONFIG_CPU_S3C2442)
2264 static struct s3c24xx_serial_drv_data s3c2440_serial_drv_data = {
2265         .info = &(struct s3c24xx_uart_info) {
2266                 .name           = "Samsung S3C2440 UART",
2267                 .type           = PORT_S3C2440,
2268                 .fifosize       = 64,
2269                 .has_divslot    = 1,
2270                 .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2271                 .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2272                 .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2273                 .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2274                 .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2275                 .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2276                 .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2277                 .num_clks       = 4,
2278                 .clksel_mask    = S3C2412_UCON_CLKMASK,
2279                 .clksel_shift   = S3C2412_UCON_CLKSHIFT,
2280         },
2281         .def_cfg = &(struct s3c2410_uartcfg) {
2282                 .ucon           = S3C2410_UCON_DEFAULT,
2283                 .ufcon          = S3C2410_UFCON_DEFAULT,
2284         },
2285 };
2286 #define S3C2440_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2440_serial_drv_data)
2287 #else
2288 #define S3C2440_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2289 #endif
2290
2291 #if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
2292 static struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
2293         .info = &(struct s3c24xx_uart_info) {
2294                 .name           = "Samsung S3C6400 UART",
2295                 .type           = PORT_S3C6400,
2296                 .fifosize       = 64,
2297                 .has_divslot    = 1,
2298                 .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2299                 .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2300                 .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2301                 .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2302                 .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2303                 .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2304                 .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2305                 .num_clks       = 4,
2306                 .clksel_mask    = S3C6400_UCON_CLKMASK,
2307                 .clksel_shift   = S3C6400_UCON_CLKSHIFT,
2308         },
2309         .def_cfg = &(struct s3c2410_uartcfg) {
2310                 .ucon           = S3C2410_UCON_DEFAULT,
2311                 .ufcon          = S3C2410_UFCON_DEFAULT,
2312         },
2313 };
2314 #define S3C6400_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c6400_serial_drv_data)
2315 #else
2316 #define S3C6400_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2317 #endif
2318
2319 #ifdef CONFIG_CPU_S5PV210
2320 static struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
2321         .info = &(struct s3c24xx_uart_info) {
2322                 .name           = "Samsung S5PV210 UART",
2323                 .type           = PORT_S3C6400,
2324                 .has_divslot    = 1,
2325                 .rx_fifomask    = S5PV210_UFSTAT_RXMASK,
2326                 .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,
2327                 .rx_fifofull    = S5PV210_UFSTAT_RXFULL,
2328                 .tx_fifofull    = S5PV210_UFSTAT_TXFULL,
2329                 .tx_fifomask    = S5PV210_UFSTAT_TXMASK,
2330                 .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,
2331                 .def_clk_sel    = S3C2410_UCON_CLKSEL0,
2332                 .num_clks       = 2,
2333                 .clksel_mask    = S5PV210_UCON_CLKMASK,
2334                 .clksel_shift   = S5PV210_UCON_CLKSHIFT,
2335         },
2336         .def_cfg = &(struct s3c2410_uartcfg) {
2337                 .ucon           = S5PV210_UCON_DEFAULT,
2338                 .ufcon          = S5PV210_UFCON_DEFAULT,
2339         },
2340         .fifosize = { 256, 64, 16, 16 },
2341 };
2342 #define S5PV210_SERIAL_DRV_DATA ((kernel_ulong_t)&s5pv210_serial_drv_data)
2343 #else
2344 #define S5PV210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2345 #endif
2346
2347 #if defined(CONFIG_ARCH_EXYNOS)
2348 #define EXYNOS_COMMON_SERIAL_DRV_DATA                           \
2349         .info = &(struct s3c24xx_uart_info) {                   \
2350                 .name           = "Samsung Exynos UART",        \
2351                 .type           = PORT_S3C6400,                 \
2352                 .has_divslot    = 1,                            \
2353                 .rx_fifomask    = S5PV210_UFSTAT_RXMASK,        \
2354                 .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,       \
2355                 .rx_fifofull    = S5PV210_UFSTAT_RXFULL,        \
2356                 .tx_fifofull    = S5PV210_UFSTAT_TXFULL,        \
2357                 .tx_fifomask    = S5PV210_UFSTAT_TXMASK,        \
2358                 .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,       \
2359                 .def_clk_sel    = S3C2410_UCON_CLKSEL0,         \
2360                 .num_clks       = 1,                            \
2361                 .clksel_mask    = 0,                            \
2362                 .clksel_shift   = 0,                            \
2363         },                                                      \
2364         .def_cfg = &(struct s3c2410_uartcfg) {                  \
2365                 .ucon           = S5PV210_UCON_DEFAULT,         \
2366                 .ufcon          = S5PV210_UFCON_DEFAULT,        \
2367                 .has_fracval    = 1,                            \
2368         }                                                       \
2369
2370 static struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
2371         EXYNOS_COMMON_SERIAL_DRV_DATA,
2372         .fifosize = { 256, 64, 16, 16 },
2373 };
2374
2375 static struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
2376         EXYNOS_COMMON_SERIAL_DRV_DATA,
2377         .fifosize = { 64, 256, 16, 256 },
2378 };
2379
2380 #define EXYNOS4210_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos4210_serial_drv_data)
2381 #define EXYNOS5433_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos5433_serial_drv_data)
2382 #else
2383 #define EXYNOS4210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2384 #define EXYNOS5433_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2385 #endif
2386
2387 static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
2388         {
2389                 .name           = "s3c2410-uart",
2390                 .driver_data    = S3C2410_SERIAL_DRV_DATA,
2391         }, {
2392                 .name           = "s3c2412-uart",
2393                 .driver_data    = S3C2412_SERIAL_DRV_DATA,
2394         }, {
2395                 .name           = "s3c2440-uart",
2396                 .driver_data    = S3C2440_SERIAL_DRV_DATA,
2397         }, {
2398                 .name           = "s3c6400-uart",
2399                 .driver_data    = S3C6400_SERIAL_DRV_DATA,
2400         }, {
2401                 .name           = "s5pv210-uart",
2402                 .driver_data    = S5PV210_SERIAL_DRV_DATA,
2403         }, {
2404                 .name           = "exynos4210-uart",
2405                 .driver_data    = EXYNOS4210_SERIAL_DRV_DATA,
2406         }, {
2407                 .name           = "exynos5433-uart",
2408                 .driver_data    = EXYNOS5433_SERIAL_DRV_DATA,
2409         },
2410         { },
2411 };
2412 MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
2413
2414 #ifdef CONFIG_OF
2415 static const struct of_device_id s3c24xx_uart_dt_match[] = {
2416         { .compatible = "samsung,s3c2410-uart",
2417                 .data = (void *)S3C2410_SERIAL_DRV_DATA },
2418         { .compatible = "samsung,s3c2412-uart",
2419                 .data = (void *)S3C2412_SERIAL_DRV_DATA },
2420         { .compatible = "samsung,s3c2440-uart",
2421                 .data = (void *)S3C2440_SERIAL_DRV_DATA },
2422         { .compatible = "samsung,s3c6400-uart",
2423                 .data = (void *)S3C6400_SERIAL_DRV_DATA },
2424         { .compatible = "samsung,s5pv210-uart",
2425                 .data = (void *)S5PV210_SERIAL_DRV_DATA },
2426         { .compatible = "samsung,exynos4210-uart",
2427                 .data = (void *)EXYNOS4210_SERIAL_DRV_DATA },
2428         { .compatible = "samsung,exynos5433-uart",
2429                 .data = (void *)EXYNOS5433_SERIAL_DRV_DATA },
2430         {},
2431 };
2432 MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
2433 #endif
2434
2435 static struct platform_driver samsung_serial_driver = {
2436         .probe          = s3c24xx_serial_probe,
2437         .remove         = s3c24xx_serial_remove,
2438         .id_table       = s3c24xx_serial_driver_ids,
2439         .driver         = {
2440                 .name   = "samsung-uart",
2441                 .pm     = SERIAL_SAMSUNG_PM_OPS,
2442                 .of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
2443         },
2444 };
2445
2446 module_platform_driver(samsung_serial_driver);
2447
2448 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2449 /*
2450  * Early console.
2451  */
2452
2453 struct samsung_early_console_data {
2454         u32 txfull_mask;
2455 };
2456
2457 static void samsung_early_busyuart(struct uart_port *port)
2458 {
2459         while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
2460                 ;
2461 }
2462
2463 static void samsung_early_busyuart_fifo(struct uart_port *port)
2464 {
2465         struct samsung_early_console_data *data = port->private_data;
2466
2467         while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
2468                 ;
2469 }
2470
2471 static void samsung_early_putc(struct uart_port *port, int c)
2472 {
2473         if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
2474                 samsung_early_busyuart_fifo(port);
2475         else
2476                 samsung_early_busyuart(port);
2477
2478         writeb(c, port->membase + S3C2410_UTXH);
2479 }
2480
2481 static void samsung_early_write(struct console *con, const char *s, unsigned n)
2482 {
2483         struct earlycon_device *dev = con->data;
2484
2485         uart_console_write(&dev->port, s, n, samsung_early_putc);
2486 }
2487
2488 static int __init samsung_early_console_setup(struct earlycon_device *device,
2489                                               const char *opt)
2490 {
2491         if (!device->port.membase)
2492                 return -ENODEV;
2493
2494         device->con->write = samsung_early_write;
2495         return 0;
2496 }
2497
2498 /* S3C2410 */
2499 static struct samsung_early_console_data s3c2410_early_console_data = {
2500         .txfull_mask = S3C2410_UFSTAT_TXFULL,
2501 };
2502
2503 static int __init s3c2410_early_console_setup(struct earlycon_device *device,
2504                                               const char *opt)
2505 {
2506         device->port.private_data = &s3c2410_early_console_data;
2507         return samsung_early_console_setup(device, opt);
2508 }
2509 OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart",
2510                         s3c2410_early_console_setup);
2511
2512 /* S3C2412, S3C2440, S3C64xx */
2513 static struct samsung_early_console_data s3c2440_early_console_data = {
2514         .txfull_mask = S3C2440_UFSTAT_TXFULL,
2515 };
2516
2517 static int __init s3c2440_early_console_setup(struct earlycon_device *device,
2518                                               const char *opt)
2519 {
2520         device->port.private_data = &s3c2440_early_console_data;
2521         return samsung_early_console_setup(device, opt);
2522 }
2523 OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart",
2524                         s3c2440_early_console_setup);
2525 OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart",
2526                         s3c2440_early_console_setup);
2527 OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
2528                         s3c2440_early_console_setup);
2529
2530 /* S5PV210, EXYNOS */
2531 static struct samsung_early_console_data s5pv210_early_console_data = {
2532         .txfull_mask = S5PV210_UFSTAT_TXFULL,
2533 };
2534
2535 static int __init s5pv210_early_console_setup(struct earlycon_device *device,
2536                                               const char *opt)
2537 {
2538         device->port.private_data = &s5pv210_early_console_data;
2539         return samsung_early_console_setup(device, opt);
2540 }
2541 OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
2542                         s5pv210_early_console_setup);
2543 OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
2544                         s5pv210_early_console_setup);
2545 #endif
2546
2547 MODULE_ALIAS("platform:samsung-uart");
2548 MODULE_DESCRIPTION("Samsung SoC Serial port driver");
2549 MODULE_AUTHOR("Ben Dooks <[email protected]>");
2550 MODULE_LICENSE("GPL v2");