linux/drivers/tty/serial/samsung.c
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   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
  55extern void printascii(const char *);
  56
  57__printf(1, 2)
  58static 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
  92static 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
  99static inline const char *s3c24xx_serial_portname(struct uart_port *port)
 100{
 101        return to_platform_device(port->dev)->name;
 102}
 103
 104static 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 */
 114static int s3c24xx_serial_has_interrupt_mask(struct uart_port *port)
 115{
 116        return to_ourport(port)->info->type == PORT_S3C6400;
 117}
 118
 119static 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
 142static 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
 157static 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
 194static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
 195
 196static 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
 227static 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
 249static 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
 275static 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
 281static 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
 316static 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
 338static 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
 358static 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
 383static 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
 414static inline struct s3c24xx_uart_info
 415        *s3c24xx_port_to_info(struct uart_port *port)
 416{
 417        return to_ourport(port)->info;
 418}
 419
 420static 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
 432static 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
 443static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
 444static 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
 476static 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
 502static 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
 525static 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
 545static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
 546
 547static 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
 589finish:
 590        spin_unlock_irqrestore(&port->lock, flags);
 591
 592        return IRQ_HANDLED;
 593}
 594
 595static 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
 681static 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
 695static 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
 704static 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
 773out:
 774        spin_unlock_irqrestore(&port->lock, flags);
 775        return IRQ_HANDLED;
 776}
 777
 778/* interrupt handler for s3c64xx and later SoC's.*/
 779static 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
 797static 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 */
 815static 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
 825static 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
 837static 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
 856static 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
 937err_unmap_rx:
 938        dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size,
 939                         DMA_FROM_DEVICE);
 940err_free_rx:
 941        kfree(dma->rx_buf);
 942err_release_tx:
 943        dma_release_channel(dma->tx_chan);
 944err_release_rx:
 945        dma_release_channel(dma->rx_chan);
 946err_warn:
 947        if (reason)
 948                dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
 949        return ret;
 950}
 951
 952static 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
 974static 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
1007static 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
1048err:
1049        s3c24xx_serial_shutdown(port);
1050        return ret;
1051}
1052
1053static 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
1106static 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
1152static 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
1165static 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
1183static 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 */
1248static 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
1267static 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
1416static 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
1434static void s3c24xx_serial_release_port(struct uart_port *port)
1435{
1436        release_mem_region(port->mapbase, MAP_SIZE);
1437}
1438
1439static 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
1445static 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 */
1457static int
1458s3c24xx_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
1471static struct console s3c24xx_serial_console;
1472
1473static int __init s3c24xx_serial_console_init(void)
1474{
1475        register_console(&s3c24xx_serial_console);
1476        return 0;
1477}
1478console_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)
1486static int s3c24xx_serial_get_poll_char(struct uart_port *port);
1487static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1488                         unsigned char c);
1489#endif
1490
1491static 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
1514static 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)
1526static struct s3c24xx_uart_port
1527s3c24xx_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
1585static 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
1610static 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
1661exit:
1662        return 0;
1663}
1664
1665static inline int
1666s3c24xx_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
1674static inline void
1675s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1676{
1677        cpufreq_unregister_notifier(&port->freq_transition,
1678                                    CPUFREQ_TRANSITION_NOTIFIER);
1679}
1680
1681#else
1682static inline int
1683s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1684{
1685        return 0;
1686}
1687
1688static inline void
1689s3c24xx_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
1699static 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
1804err:
1805        port->mapbase = 0;
1806        return ret;
1807}
1808
1809/* Device driver serial port probe */
1810
1811static const struct of_device_id s3c24xx_uart_dt_match[];
1812static int probe_index;
1813
1814static 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
1828static 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
1911static 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
1927static 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
1937static 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                s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1945                clk_disable_unprepare(ourport->clk);
1946
1947                uart_resume_port(&s3c24xx_uart_drv, port);
1948        }
1949
1950        return 0;
1951}
1952
1953static int s3c24xx_serial_resume_noirq(struct device *dev)
1954{
1955        struct uart_port *port = s3c24xx_dev_to_port(dev);
1956        struct s3c24xx_uart_port *ourport = to_ourport(port);
1957
1958        if (port) {
1959                /* restore IRQ mask */
1960                if (s3c24xx_serial_has_interrupt_mask(port)) {
1961                        unsigned int uintm = 0xf;
1962                        if (tx_enabled(port))
1963                                uintm &= ~S3C64XX_UINTM_TXD_MSK;
1964                        if (rx_enabled(port))
1965                                uintm &= ~S3C64XX_UINTM_RXD_MSK;
1966                        clk_prepare_enable(ourport->clk);
1967                        wr_regl(port, S3C64XX_UINTM, uintm);
1968                        clk_disable_unprepare(ourport->clk);
1969                }
1970        }
1971
1972        return 0;
1973}
1974
1975static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
1976        .suspend = s3c24xx_serial_suspend,
1977        .resume = s3c24xx_serial_resume,
1978        .resume_noirq = s3c24xx_serial_resume_noirq,
1979};
1980#define SERIAL_SAMSUNG_PM_OPS   (&s3c24xx_serial_pm_ops)
1981
1982#else /* !CONFIG_PM_SLEEP */
1983
1984#define SERIAL_SAMSUNG_PM_OPS   NULL
1985#endif /* CONFIG_PM_SLEEP */
1986
1987/* Console code */
1988
1989#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1990
1991static struct uart_port *cons_uart;
1992
1993static int
1994s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
1995{
1996        struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1997        unsigned long ufstat, utrstat;
1998
1999        if (ufcon & S3C2410_UFCON_FIFOMODE) {
2000                /* fifo mode - check amount of data in fifo registers... */
2001
2002                ufstat = rd_regl(port, S3C2410_UFSTAT);
2003                return (ufstat & info->tx_fifofull) ? 0 : 1;
2004        }
2005
2006        /* in non-fifo mode, we go and use the tx buffer empty */
2007
2008        utrstat = rd_regl(port, S3C2410_UTRSTAT);
2009        return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
2010}
2011
2012static bool
2013s3c24xx_port_configured(unsigned int ucon)
2014{
2015        /* consider the serial port configured if the tx/rx mode set */
2016        return (ucon & 0xf) != 0;
2017}
2018
2019#ifdef CONFIG_CONSOLE_POLL
2020/*
2021 * Console polling routines for writing and reading from the uart while
2022 * in an interrupt or debug context.
2023 */
2024
2025static int s3c24xx_serial_get_poll_char(struct uart_port *port)
2026{
2027        struct s3c24xx_uart_port *ourport = to_ourport(port);
2028        unsigned int ufstat;
2029
2030        ufstat = rd_regl(port, S3C2410_UFSTAT);
2031        if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
2032                return NO_POLL_CHAR;
2033
2034        return rd_regb(port, S3C2410_URXH);
2035}
2036
2037static void s3c24xx_serial_put_poll_char(struct uart_port *port,
2038                unsigned char c)
2039{
2040        unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2041        unsigned int ucon = rd_regl(port, S3C2410_UCON);
2042
2043        /* not possible to xmit on unconfigured port */
2044        if (!s3c24xx_port_configured(ucon))
2045                return;
2046
2047        while (!s3c24xx_serial_console_txrdy(port, ufcon))
2048                cpu_relax();
2049        wr_regb(port, S3C2410_UTXH, c);
2050}
2051
2052#endif /* CONFIG_CONSOLE_POLL */
2053
2054static void
2055s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
2056{
2057        unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2058
2059        while (!s3c24xx_serial_console_txrdy(port, ufcon))
2060                cpu_relax();
2061        wr_regb(port, S3C2410_UTXH, ch);
2062}
2063
2064static void
2065s3c24xx_serial_console_write(struct console *co, const char *s,
2066                             unsigned int count)
2067{
2068        unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
2069
2070        /* not possible to xmit on unconfigured port */
2071        if (!s3c24xx_port_configured(ucon))
2072                return;
2073
2074        uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
2075}
2076
2077static void __init
2078s3c24xx_serial_get_options(struct uart_port *port, int *baud,
2079                           int *parity, int *bits)
2080{
2081        struct clk *clk;
2082        unsigned int ulcon;
2083        unsigned int ucon;
2084        unsigned int ubrdiv;
2085        unsigned long rate;
2086        unsigned int clk_sel;
2087        char clk_name[MAX_CLK_NAME_LENGTH];
2088
2089        ulcon  = rd_regl(port, S3C2410_ULCON);
2090        ucon   = rd_regl(port, S3C2410_UCON);
2091        ubrdiv = rd_regl(port, S3C2410_UBRDIV);
2092
2093        dbg("s3c24xx_serial_get_options: port=%p\n"
2094            "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
2095            port, ulcon, ucon, ubrdiv);
2096
2097        if (s3c24xx_port_configured(ucon)) {
2098                switch (ulcon & S3C2410_LCON_CSMASK) {
2099                case S3C2410_LCON_CS5:
2100                        *bits = 5;
2101                        break;
2102                case S3C2410_LCON_CS6:
2103                        *bits = 6;
2104                        break;
2105                case S3C2410_LCON_CS7:
2106                        *bits = 7;
2107                        break;
2108                case S3C2410_LCON_CS8:
2109                default:
2110                        *bits = 8;
2111                        break;
2112                }
2113
2114                switch (ulcon & S3C2410_LCON_PMASK) {
2115                case S3C2410_LCON_PEVEN:
2116                        *parity = 'e';
2117                        break;
2118
2119                case S3C2410_LCON_PODD:
2120                        *parity = 'o';
2121                        break;
2122
2123                case S3C2410_LCON_PNONE:
2124                default:
2125                        *parity = 'n';
2126                }
2127
2128                /* now calculate the baud rate */
2129
2130                clk_sel = s3c24xx_serial_getsource(port);
2131                sprintf(clk_name, "clk_uart_baud%d", clk_sel);
2132
2133                clk = clk_get(port->dev, clk_name);
2134                if (!IS_ERR(clk))
2135                        rate = clk_get_rate(clk);
2136                else
2137                        rate = 1;
2138
2139                *baud = rate / (16 * (ubrdiv + 1));
2140                dbg("calculated baud %d\n", *baud);
2141        }
2142
2143}
2144
2145static int __init
2146s3c24xx_serial_console_setup(struct console *co, char *options)
2147{
2148        struct uart_port *port;
2149        int baud = 9600;
2150        int bits = 8;
2151        int parity = 'n';
2152        int flow = 'n';
2153
2154        dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
2155            co, co->index, options);
2156
2157        /* is this a valid port */
2158
2159        if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
2160                co->index = 0;
2161
2162        port = &s3c24xx_serial_ports[co->index].port;
2163
2164        /* is the port configured? */
2165
2166        if (port->mapbase == 0x0)
2167                return -ENODEV;
2168
2169        cons_uart = port;
2170
2171        dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
2172
2173        /*
2174         * Check whether an invalid uart number has been specified, and
2175         * if so, search for the first available port that does have
2176         * console support.
2177         */
2178        if (options)
2179                uart_parse_options(options, &baud, &parity, &bits, &flow);
2180        else
2181                s3c24xx_serial_get_options(port, &baud, &parity, &bits);
2182
2183        dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
2184
2185        return uart_set_options(port, co, baud, parity, bits, flow);
2186}
2187
2188static struct console s3c24xx_serial_console = {
2189        .name           = S3C24XX_SERIAL_NAME,
2190        .device         = uart_console_device,
2191        .flags          = CON_PRINTBUFFER,
2192        .index          = -1,
2193        .write          = s3c24xx_serial_console_write,
2194        .setup          = s3c24xx_serial_console_setup,
2195        .data           = &s3c24xx_uart_drv,
2196};
2197#endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
2198
2199#ifdef CONFIG_CPU_S3C2410
2200static struct s3c24xx_serial_drv_data s3c2410_serial_drv_data = {
2201        .info = &(struct s3c24xx_uart_info) {
2202                .name           = "Samsung S3C2410 UART",
2203                .type           = PORT_S3C2410,
2204                .fifosize       = 16,
2205                .rx_fifomask    = S3C2410_UFSTAT_RXMASK,
2206                .rx_fifoshift   = S3C2410_UFSTAT_RXSHIFT,
2207                .rx_fifofull    = S3C2410_UFSTAT_RXFULL,
2208                .tx_fifofull    = S3C2410_UFSTAT_TXFULL,
2209                .tx_fifomask    = S3C2410_UFSTAT_TXMASK,
2210                .tx_fifoshift   = S3C2410_UFSTAT_TXSHIFT,
2211                .def_clk_sel    = S3C2410_UCON_CLKSEL0,
2212                .num_clks       = 2,
2213                .clksel_mask    = S3C2410_UCON_CLKMASK,
2214                .clksel_shift   = S3C2410_UCON_CLKSHIFT,
2215        },
2216        .def_cfg = &(struct s3c2410_uartcfg) {
2217                .ucon           = S3C2410_UCON_DEFAULT,
2218                .ufcon          = S3C2410_UFCON_DEFAULT,
2219        },
2220};
2221#define S3C2410_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2410_serial_drv_data)
2222#else
2223#define S3C2410_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2224#endif
2225
2226#ifdef CONFIG_CPU_S3C2412
2227static struct s3c24xx_serial_drv_data s3c2412_serial_drv_data = {
2228        .info = &(struct s3c24xx_uart_info) {
2229                .name           = "Samsung S3C2412 UART",
2230                .type           = PORT_S3C2412,
2231                .fifosize       = 64,
2232                .has_divslot    = 1,
2233                .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2234                .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2235                .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2236                .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2237                .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2238                .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2239                .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2240                .num_clks       = 4,
2241                .clksel_mask    = S3C2412_UCON_CLKMASK,
2242                .clksel_shift   = S3C2412_UCON_CLKSHIFT,
2243        },
2244        .def_cfg = &(struct s3c2410_uartcfg) {
2245                .ucon           = S3C2410_UCON_DEFAULT,
2246                .ufcon          = S3C2410_UFCON_DEFAULT,
2247        },
2248};
2249#define S3C2412_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2412_serial_drv_data)
2250#else
2251#define S3C2412_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2252#endif
2253
2254#if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2416) || \
2255        defined(CONFIG_CPU_S3C2443) || defined(CONFIG_CPU_S3C2442)
2256static struct s3c24xx_serial_drv_data s3c2440_serial_drv_data = {
2257        .info = &(struct s3c24xx_uart_info) {
2258                .name           = "Samsung S3C2440 UART",
2259                .type           = PORT_S3C2440,
2260                .fifosize       = 64,
2261                .has_divslot    = 1,
2262                .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2263                .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2264                .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2265                .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2266                .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2267                .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2268                .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2269                .num_clks       = 4,
2270                .clksel_mask    = S3C2412_UCON_CLKMASK,
2271                .clksel_shift   = S3C2412_UCON_CLKSHIFT,
2272        },
2273        .def_cfg = &(struct s3c2410_uartcfg) {
2274                .ucon           = S3C2410_UCON_DEFAULT,
2275                .ufcon          = S3C2410_UFCON_DEFAULT,
2276        },
2277};
2278#define S3C2440_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2440_serial_drv_data)
2279#else
2280#define S3C2440_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2281#endif
2282
2283#if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
2284static struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
2285        .info = &(struct s3c24xx_uart_info) {
2286                .name           = "Samsung S3C6400 UART",
2287                .type           = PORT_S3C6400,
2288                .fifosize       = 64,
2289                .has_divslot    = 1,
2290                .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2291                .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2292                .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2293                .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2294                .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2295                .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2296                .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2297                .num_clks       = 4,
2298                .clksel_mask    = S3C6400_UCON_CLKMASK,
2299                .clksel_shift   = S3C6400_UCON_CLKSHIFT,
2300        },
2301        .def_cfg = &(struct s3c2410_uartcfg) {
2302                .ucon           = S3C2410_UCON_DEFAULT,
2303                .ufcon          = S3C2410_UFCON_DEFAULT,
2304        },
2305};
2306#define S3C6400_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c6400_serial_drv_data)
2307#else
2308#define S3C6400_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2309#endif
2310
2311#ifdef CONFIG_CPU_S5PV210
2312static struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
2313        .info = &(struct s3c24xx_uart_info) {
2314                .name           = "Samsung S5PV210 UART",
2315                .type           = PORT_S3C6400,
2316                .has_divslot    = 1,
2317                .rx_fifomask    = S5PV210_UFSTAT_RXMASK,
2318                .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,
2319                .rx_fifofull    = S5PV210_UFSTAT_RXFULL,
2320                .tx_fifofull    = S5PV210_UFSTAT_TXFULL,
2321                .tx_fifomask    = S5PV210_UFSTAT_TXMASK,
2322                .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,
2323                .def_clk_sel    = S3C2410_UCON_CLKSEL0,
2324                .num_clks       = 2,
2325                .clksel_mask    = S5PV210_UCON_CLKMASK,
2326                .clksel_shift   = S5PV210_UCON_CLKSHIFT,
2327        },
2328        .def_cfg = &(struct s3c2410_uartcfg) {
2329                .ucon           = S5PV210_UCON_DEFAULT,
2330                .ufcon          = S5PV210_UFCON_DEFAULT,
2331        },
2332        .fifosize = { 256, 64, 16, 16 },
2333};
2334#define S5PV210_SERIAL_DRV_DATA ((kernel_ulong_t)&s5pv210_serial_drv_data)
2335#else
2336#define S5PV210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2337#endif
2338
2339#if defined(CONFIG_ARCH_EXYNOS)
2340#define EXYNOS_COMMON_SERIAL_DRV_DATA                           \
2341        .info = &(struct s3c24xx_uart_info) {                   \
2342                .name           = "Samsung Exynos UART",        \
2343                .type           = PORT_S3C6400,                 \
2344                .has_divslot    = 1,                            \
2345                .rx_fifomask    = S5PV210_UFSTAT_RXMASK,        \
2346                .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,       \
2347                .rx_fifofull    = S5PV210_UFSTAT_RXFULL,        \
2348                .tx_fifofull    = S5PV210_UFSTAT_TXFULL,        \
2349                .tx_fifomask    = S5PV210_UFSTAT_TXMASK,        \
2350                .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,       \
2351                .def_clk_sel    = S3C2410_UCON_CLKSEL0,         \
2352                .num_clks       = 1,                            \
2353                .clksel_mask    = 0,                            \
2354                .clksel_shift   = 0,                            \
2355        },                                                      \
2356        .def_cfg = &(struct s3c2410_uartcfg) {                  \
2357                .ucon           = S5PV210_UCON_DEFAULT,         \
2358                .ufcon          = S5PV210_UFCON_DEFAULT,        \
2359                .has_fracval    = 1,                            \
2360        }                                                       \
2361
2362static struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
2363        EXYNOS_COMMON_SERIAL_DRV_DATA,
2364        .fifosize = { 256, 64, 16, 16 },
2365};
2366
2367static struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
2368        EXYNOS_COMMON_SERIAL_DRV_DATA,
2369        .fifosize = { 64, 256, 16, 256 },
2370};
2371
2372#define EXYNOS4210_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos4210_serial_drv_data)
2373#define EXYNOS5433_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos5433_serial_drv_data)
2374#else
2375#define EXYNOS4210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2376#define EXYNOS5433_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2377#endif
2378
2379static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
2380        {
2381                .name           = "s3c2410-uart",
2382                .driver_data    = S3C2410_SERIAL_DRV_DATA,
2383        }, {
2384                .name           = "s3c2412-uart",
2385                .driver_data    = S3C2412_SERIAL_DRV_DATA,
2386        }, {
2387                .name           = "s3c2440-uart",
2388                .driver_data    = S3C2440_SERIAL_DRV_DATA,
2389        }, {
2390                .name           = "s3c6400-uart",
2391                .driver_data    = S3C6400_SERIAL_DRV_DATA,
2392        }, {
2393                .name           = "s5pv210-uart",
2394                .driver_data    = S5PV210_SERIAL_DRV_DATA,
2395        }, {
2396                .name           = "exynos4210-uart",
2397                .driver_data    = EXYNOS4210_SERIAL_DRV_DATA,
2398        }, {
2399                .name           = "exynos5433-uart",
2400                .driver_data    = EXYNOS5433_SERIAL_DRV_DATA,
2401        },
2402        { },
2403};
2404MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
2405
2406#ifdef CONFIG_OF
2407static const struct of_device_id s3c24xx_uart_dt_match[] = {
2408        { .compatible = "samsung,s3c2410-uart",
2409                .data = (void *)S3C2410_SERIAL_DRV_DATA },
2410        { .compatible = "samsung,s3c2412-uart",
2411                .data = (void *)S3C2412_SERIAL_DRV_DATA },
2412        { .compatible = "samsung,s3c2440-uart",
2413                .data = (void *)S3C2440_SERIAL_DRV_DATA },
2414        { .compatible = "samsung,s3c6400-uart",
2415                .data = (void *)S3C6400_SERIAL_DRV_DATA },
2416        { .compatible = "samsung,s5pv210-uart",
2417                .data = (void *)S5PV210_SERIAL_DRV_DATA },
2418        { .compatible = "samsung,exynos4210-uart",
2419                .data = (void *)EXYNOS4210_SERIAL_DRV_DATA },
2420        { .compatible = "samsung,exynos5433-uart",
2421                .data = (void *)EXYNOS5433_SERIAL_DRV_DATA },
2422        {},
2423};
2424MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
2425#endif
2426
2427static struct platform_driver samsung_serial_driver = {
2428        .probe          = s3c24xx_serial_probe,
2429        .remove         = s3c24xx_serial_remove,
2430        .id_table       = s3c24xx_serial_driver_ids,
2431        .driver         = {
2432                .name   = "samsung-uart",
2433                .pm     = SERIAL_SAMSUNG_PM_OPS,
2434                .of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
2435        },
2436};
2437
2438module_platform_driver(samsung_serial_driver);
2439
2440#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2441/*
2442 * Early console.
2443 */
2444
2445struct samsung_early_console_data {
2446        u32 txfull_mask;
2447};
2448
2449static void samsung_early_busyuart(struct uart_port *port)
2450{
2451        while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
2452                ;
2453}
2454
2455static void samsung_early_busyuart_fifo(struct uart_port *port)
2456{
2457        struct samsung_early_console_data *data = port->private_data;
2458
2459        while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
2460                ;
2461}
2462
2463static void samsung_early_putc(struct uart_port *port, int c)
2464{
2465        if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
2466                samsung_early_busyuart_fifo(port);
2467        else
2468                samsung_early_busyuart(port);
2469
2470        writeb(c, port->membase + S3C2410_UTXH);
2471}
2472
2473static void samsung_early_write(struct console *con, const char *s, unsigned n)
2474{
2475        struct earlycon_device *dev = con->data;
2476
2477        uart_console_write(&dev->port, s, n, samsung_early_putc);
2478}
2479
2480static int __init samsung_early_console_setup(struct earlycon_device *device,
2481                                              const char *opt)
2482{
2483        if (!device->port.membase)
2484                return -ENODEV;
2485
2486        device->con->write = samsung_early_write;
2487        return 0;
2488}
2489
2490/* S3C2410 */
2491static struct samsung_early_console_data s3c2410_early_console_data = {
2492        .txfull_mask = S3C2410_UFSTAT_TXFULL,
2493};
2494
2495static int __init s3c2410_early_console_setup(struct earlycon_device *device,
2496                                              const char *opt)
2497{
2498        device->port.private_data = &s3c2410_early_console_data;
2499        return samsung_early_console_setup(device, opt);
2500}
2501OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart",
2502                        s3c2410_early_console_setup);
2503
2504/* S3C2412, S3C2440, S3C64xx */
2505static struct samsung_early_console_data s3c2440_early_console_data = {
2506        .txfull_mask = S3C2440_UFSTAT_TXFULL,
2507};
2508
2509static int __init s3c2440_early_console_setup(struct earlycon_device *device,
2510                                              const char *opt)
2511{
2512        device->port.private_data = &s3c2440_early_console_data;
2513        return samsung_early_console_setup(device, opt);
2514}
2515OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart",
2516                        s3c2440_early_console_setup);
2517OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart",
2518                        s3c2440_early_console_setup);
2519OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
2520                        s3c2440_early_console_setup);
2521
2522/* S5PV210, EXYNOS */
2523static struct samsung_early_console_data s5pv210_early_console_data = {
2524        .txfull_mask = S5PV210_UFSTAT_TXFULL,
2525};
2526
2527static int __init s5pv210_early_console_setup(struct earlycon_device *device,
2528                                              const char *opt)
2529{
2530        device->port.private_data = &s5pv210_early_console_data;
2531        return samsung_early_console_setup(device, opt);
2532}
2533OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
2534                        s5pv210_early_console_setup);
2535OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
2536                        s5pv210_early_console_setup);
2537#endif
2538
2539MODULE_ALIAS("platform:samsung-uart");
2540MODULE_DESCRIPTION("Samsung SoC Serial port driver");
2541MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
2542MODULE_LICENSE("GPL v2");
2543