linux/drivers/tty/serial/sccnxp.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *  NXP (Philips) SCC+++(SCN+++) serial driver
   4 *
   5 *  Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
   6 *
   7 *  Based on sc26xx.c, by Thomas Bogendörfer (tsbogend@alpha.franken.de)
   8 */
   9
  10#if defined(CONFIG_SERIAL_SCCNXP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  11#define SUPPORT_SYSRQ
  12#endif
  13
  14#include <linux/clk.h>
  15#include <linux/err.h>
  16#include <linux/module.h>
  17#include <linux/device.h>
  18#include <linux/console.h>
  19#include <linux/serial_core.h>
  20#include <linux/serial.h>
  21#include <linux/io.h>
  22#include <linux/tty.h>
  23#include <linux/tty_flip.h>
  24#include <linux/spinlock.h>
  25#include <linux/platform_device.h>
  26#include <linux/platform_data/serial-sccnxp.h>
  27#include <linux/regulator/consumer.h>
  28
  29#define SCCNXP_NAME                     "uart-sccnxp"
  30#define SCCNXP_MAJOR                    204
  31#define SCCNXP_MINOR                    205
  32
  33#define SCCNXP_MR_REG                   (0x00)
  34#       define MR0_BAUD_NORMAL          (0 << 0)
  35#       define MR0_BAUD_EXT1            (1 << 0)
  36#       define MR0_BAUD_EXT2            (5 << 0)
  37#       define MR0_FIFO                 (1 << 3)
  38#       define MR0_TXLVL                (1 << 4)
  39#       define MR1_BITS_5               (0 << 0)
  40#       define MR1_BITS_6               (1 << 0)
  41#       define MR1_BITS_7               (2 << 0)
  42#       define MR1_BITS_8               (3 << 0)
  43#       define MR1_PAR_EVN              (0 << 2)
  44#       define MR1_PAR_ODD              (1 << 2)
  45#       define MR1_PAR_NO               (4 << 2)
  46#       define MR2_STOP1                (7 << 0)
  47#       define MR2_STOP2                (0xf << 0)
  48#define SCCNXP_SR_REG                   (0x01)
  49#define SCCNXP_CSR_REG                  SCCNXP_SR_REG
  50#       define SR_RXRDY                 (1 << 0)
  51#       define SR_FULL                  (1 << 1)
  52#       define SR_TXRDY                 (1 << 2)
  53#       define SR_TXEMT                 (1 << 3)
  54#       define SR_OVR                   (1 << 4)
  55#       define SR_PE                    (1 << 5)
  56#       define SR_FE                    (1 << 6)
  57#       define SR_BRK                   (1 << 7)
  58#define SCCNXP_CR_REG                   (0x02)
  59#       define CR_RX_ENABLE             (1 << 0)
  60#       define CR_RX_DISABLE            (1 << 1)
  61#       define CR_TX_ENABLE             (1 << 2)
  62#       define CR_TX_DISABLE            (1 << 3)
  63#       define CR_CMD_MRPTR1            (0x01 << 4)
  64#       define CR_CMD_RX_RESET          (0x02 << 4)
  65#       define CR_CMD_TX_RESET          (0x03 << 4)
  66#       define CR_CMD_STATUS_RESET      (0x04 << 4)
  67#       define CR_CMD_BREAK_RESET       (0x05 << 4)
  68#       define CR_CMD_START_BREAK       (0x06 << 4)
  69#       define CR_CMD_STOP_BREAK        (0x07 << 4)
  70#       define CR_CMD_MRPTR0            (0x0b << 4)
  71#define SCCNXP_RHR_REG                  (0x03)
  72#define SCCNXP_THR_REG                  SCCNXP_RHR_REG
  73#define SCCNXP_IPCR_REG                 (0x04)
  74#define SCCNXP_ACR_REG                  SCCNXP_IPCR_REG
  75#       define ACR_BAUD0                (0 << 7)
  76#       define ACR_BAUD1                (1 << 7)
  77#       define ACR_TIMER_MODE           (6 << 4)
  78#define SCCNXP_ISR_REG                  (0x05)
  79#define SCCNXP_IMR_REG                  SCCNXP_ISR_REG
  80#       define IMR_TXRDY                (1 << 0)
  81#       define IMR_RXRDY                (1 << 1)
  82#       define ISR_TXRDY(x)             (1 << ((x * 4) + 0))
  83#       define ISR_RXRDY(x)             (1 << ((x * 4) + 1))
  84#define SCCNXP_IPR_REG                  (0x0d)
  85#define SCCNXP_OPCR_REG                 SCCNXP_IPR_REG
  86#define SCCNXP_SOP_REG                  (0x0e)
  87#define SCCNXP_ROP_REG                  (0x0f)
  88
  89/* Route helpers */
  90#define MCTRL_MASK(sig)                 (0xf << (sig))
  91#define MCTRL_IBIT(cfg, sig)            ((((cfg) >> (sig)) & 0xf) - LINE_IP0)
  92#define MCTRL_OBIT(cfg, sig)            ((((cfg) >> (sig)) & 0xf) - LINE_OP0)
  93
  94#define SCCNXP_HAVE_IO          0x00000001
  95#define SCCNXP_HAVE_MR0         0x00000002
  96
  97struct sccnxp_chip {
  98        const char              *name;
  99        unsigned int            nr;
 100        unsigned long           freq_min;
 101        unsigned long           freq_std;
 102        unsigned long           freq_max;
 103        unsigned int            flags;
 104        unsigned int            fifosize;
 105};
 106
 107struct sccnxp_port {
 108        struct uart_driver      uart;
 109        struct uart_port        port[SCCNXP_MAX_UARTS];
 110        bool                    opened[SCCNXP_MAX_UARTS];
 111
 112        int                     irq;
 113        u8                      imr;
 114
 115        struct sccnxp_chip      *chip;
 116
 117#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
 118        struct console          console;
 119#endif
 120
 121        spinlock_t              lock;
 122
 123        bool                    poll;
 124        struct timer_list       timer;
 125
 126        struct sccnxp_pdata     pdata;
 127
 128        struct regulator        *regulator;
 129};
 130
 131static const struct sccnxp_chip sc2681 = {
 132        .name           = "SC2681",
 133        .nr             = 2,
 134        .freq_min       = 1000000,
 135        .freq_std       = 3686400,
 136        .freq_max       = 4000000,
 137        .flags          = SCCNXP_HAVE_IO,
 138        .fifosize       = 3,
 139};
 140
 141static const struct sccnxp_chip sc2691 = {
 142        .name           = "SC2691",
 143        .nr             = 1,
 144        .freq_min       = 1000000,
 145        .freq_std       = 3686400,
 146        .freq_max       = 4000000,
 147        .flags          = 0,
 148        .fifosize       = 3,
 149};
 150
 151static const struct sccnxp_chip sc2692 = {
 152        .name           = "SC2692",
 153        .nr             = 2,
 154        .freq_min       = 1000000,
 155        .freq_std       = 3686400,
 156        .freq_max       = 4000000,
 157        .flags          = SCCNXP_HAVE_IO,
 158        .fifosize       = 3,
 159};
 160
 161static const struct sccnxp_chip sc2891 = {
 162        .name           = "SC2891",
 163        .nr             = 1,
 164        .freq_min       = 100000,
 165        .freq_std       = 3686400,
 166        .freq_max       = 8000000,
 167        .flags          = SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
 168        .fifosize       = 16,
 169};
 170
 171static const struct sccnxp_chip sc2892 = {
 172        .name           = "SC2892",
 173        .nr             = 2,
 174        .freq_min       = 100000,
 175        .freq_std       = 3686400,
 176        .freq_max       = 8000000,
 177        .flags          = SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
 178        .fifosize       = 16,
 179};
 180
 181static const struct sccnxp_chip sc28202 = {
 182        .name           = "SC28202",
 183        .nr             = 2,
 184        .freq_min       = 1000000,
 185        .freq_std       = 14745600,
 186        .freq_max       = 50000000,
 187        .flags          = SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
 188        .fifosize       = 256,
 189};
 190
 191static const struct sccnxp_chip sc68681 = {
 192        .name           = "SC68681",
 193        .nr             = 2,
 194        .freq_min       = 1000000,
 195        .freq_std       = 3686400,
 196        .freq_max       = 4000000,
 197        .flags          = SCCNXP_HAVE_IO,
 198        .fifosize       = 3,
 199};
 200
 201static const struct sccnxp_chip sc68692 = {
 202        .name           = "SC68692",
 203        .nr             = 2,
 204        .freq_min       = 1000000,
 205        .freq_std       = 3686400,
 206        .freq_max       = 4000000,
 207        .flags          = SCCNXP_HAVE_IO,
 208        .fifosize       = 3,
 209};
 210
 211static inline u8 sccnxp_read(struct uart_port *port, u8 reg)
 212{
 213        return readb(port->membase + (reg << port->regshift));
 214}
 215
 216static inline void sccnxp_write(struct uart_port *port, u8 reg, u8 v)
 217{
 218        writeb(v, port->membase + (reg << port->regshift));
 219}
 220
 221static inline u8 sccnxp_port_read(struct uart_port *port, u8 reg)
 222{
 223        return sccnxp_read(port, (port->line << 3) + reg);
 224}
 225
 226static inline void sccnxp_port_write(struct uart_port *port, u8 reg, u8 v)
 227{
 228        sccnxp_write(port, (port->line << 3) + reg, v);
 229}
 230
 231static int sccnxp_update_best_err(int a, int b, int *besterr)
 232{
 233        int err = abs(a - b);
 234
 235        if ((*besterr < 0) || (*besterr > err)) {
 236                *besterr = err;
 237                return 0;
 238        }
 239
 240        return 1;
 241}
 242
 243static const struct {
 244        u8      csr;
 245        u8      acr;
 246        u8      mr0;
 247        int     baud;
 248} baud_std[] = {
 249        { 0,    ACR_BAUD0,      MR0_BAUD_NORMAL,        50, },
 250        { 0,    ACR_BAUD1,      MR0_BAUD_NORMAL,        75, },
 251        { 1,    ACR_BAUD0,      MR0_BAUD_NORMAL,        110, },
 252        { 2,    ACR_BAUD0,      MR0_BAUD_NORMAL,        134, },
 253        { 3,    ACR_BAUD1,      MR0_BAUD_NORMAL,        150, },
 254        { 3,    ACR_BAUD0,      MR0_BAUD_NORMAL,        200, },
 255        { 4,    ACR_BAUD0,      MR0_BAUD_NORMAL,        300, },
 256        { 0,    ACR_BAUD1,      MR0_BAUD_EXT1,          450, },
 257        { 1,    ACR_BAUD0,      MR0_BAUD_EXT2,          880, },
 258        { 3,    ACR_BAUD1,      MR0_BAUD_EXT1,          900, },
 259        { 5,    ACR_BAUD0,      MR0_BAUD_NORMAL,        600, },
 260        { 7,    ACR_BAUD0,      MR0_BAUD_NORMAL,        1050, },
 261        { 2,    ACR_BAUD0,      MR0_BAUD_EXT2,          1076, },
 262        { 6,    ACR_BAUD0,      MR0_BAUD_NORMAL,        1200, },
 263        { 10,   ACR_BAUD1,      MR0_BAUD_NORMAL,        1800, },
 264        { 7,    ACR_BAUD1,      MR0_BAUD_NORMAL,        2000, },
 265        { 8,    ACR_BAUD0,      MR0_BAUD_NORMAL,        2400, },
 266        { 5,    ACR_BAUD1,      MR0_BAUD_EXT1,          3600, },
 267        { 9,    ACR_BAUD0,      MR0_BAUD_NORMAL,        4800, },
 268        { 10,   ACR_BAUD0,      MR0_BAUD_NORMAL,        7200, },
 269        { 11,   ACR_BAUD0,      MR0_BAUD_NORMAL,        9600, },
 270        { 8,    ACR_BAUD0,      MR0_BAUD_EXT1,          14400, },
 271        { 12,   ACR_BAUD1,      MR0_BAUD_NORMAL,        19200, },
 272        { 9,    ACR_BAUD0,      MR0_BAUD_EXT1,          28800, },
 273        { 12,   ACR_BAUD0,      MR0_BAUD_NORMAL,        38400, },
 274        { 11,   ACR_BAUD0,      MR0_BAUD_EXT1,          57600, },
 275        { 12,   ACR_BAUD1,      MR0_BAUD_EXT1,          115200, },
 276        { 12,   ACR_BAUD0,      MR0_BAUD_EXT1,          230400, },
 277        { 0, 0, 0, 0 }
 278};
 279
 280static int sccnxp_set_baud(struct uart_port *port, int baud)
 281{
 282        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 283        int div_std, tmp_baud, bestbaud = baud, besterr = -1;
 284        struct sccnxp_chip *chip = s->chip;
 285        u8 i, acr = 0, csr = 0, mr0 = 0;
 286
 287        /* Find best baud from table */
 288        for (i = 0; baud_std[i].baud && besterr; i++) {
 289                if (baud_std[i].mr0 && !(chip->flags & SCCNXP_HAVE_MR0))
 290                        continue;
 291                div_std = DIV_ROUND_CLOSEST(chip->freq_std, baud_std[i].baud);
 292                tmp_baud = DIV_ROUND_CLOSEST(port->uartclk, div_std);
 293                if (!sccnxp_update_best_err(baud, tmp_baud, &besterr)) {
 294                        acr = baud_std[i].acr;
 295                        csr = baud_std[i].csr;
 296                        mr0 = baud_std[i].mr0;
 297                        bestbaud = tmp_baud;
 298                }
 299        }
 300
 301        if (chip->flags & SCCNXP_HAVE_MR0) {
 302                /* Enable FIFO, set half level for TX */
 303                mr0 |= MR0_FIFO | MR0_TXLVL;
 304                /* Update MR0 */
 305                sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR0);
 306                sccnxp_port_write(port, SCCNXP_MR_REG, mr0);
 307        }
 308
 309        sccnxp_port_write(port, SCCNXP_ACR_REG, acr | ACR_TIMER_MODE);
 310        sccnxp_port_write(port, SCCNXP_CSR_REG, (csr << 4) | csr);
 311
 312        if (baud != bestbaud)
 313                dev_dbg(port->dev, "Baudrate desired: %i, calculated: %i\n",
 314                        baud, bestbaud);
 315
 316        return bestbaud;
 317}
 318
 319static void sccnxp_enable_irq(struct uart_port *port, int mask)
 320{
 321        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 322
 323        s->imr |= mask << (port->line * 4);
 324        sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
 325}
 326
 327static void sccnxp_disable_irq(struct uart_port *port, int mask)
 328{
 329        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 330
 331        s->imr &= ~(mask << (port->line * 4));
 332        sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
 333}
 334
 335static void sccnxp_set_bit(struct uart_port *port, int sig, int state)
 336{
 337        u8 bitmask;
 338        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 339
 340        if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(sig)) {
 341                bitmask = 1 << MCTRL_OBIT(s->pdata.mctrl_cfg[port->line], sig);
 342                if (state)
 343                        sccnxp_write(port, SCCNXP_SOP_REG, bitmask);
 344                else
 345                        sccnxp_write(port, SCCNXP_ROP_REG, bitmask);
 346        }
 347}
 348
 349static void sccnxp_handle_rx(struct uart_port *port)
 350{
 351        u8 sr;
 352        unsigned int ch, flag;
 353
 354        for (;;) {
 355                sr = sccnxp_port_read(port, SCCNXP_SR_REG);
 356                if (!(sr & SR_RXRDY))
 357                        break;
 358                sr &= SR_PE | SR_FE | SR_OVR | SR_BRK;
 359
 360                ch = sccnxp_port_read(port, SCCNXP_RHR_REG);
 361
 362                port->icount.rx++;
 363                flag = TTY_NORMAL;
 364
 365                if (unlikely(sr)) {
 366                        if (sr & SR_BRK) {
 367                                port->icount.brk++;
 368                                sccnxp_port_write(port, SCCNXP_CR_REG,
 369                                                  CR_CMD_BREAK_RESET);
 370                                if (uart_handle_break(port))
 371                                        continue;
 372                        } else if (sr & SR_PE)
 373                                port->icount.parity++;
 374                        else if (sr & SR_FE)
 375                                port->icount.frame++;
 376                        else if (sr & SR_OVR) {
 377                                port->icount.overrun++;
 378                                sccnxp_port_write(port, SCCNXP_CR_REG,
 379                                                  CR_CMD_STATUS_RESET);
 380                        }
 381
 382                        sr &= port->read_status_mask;
 383                        if (sr & SR_BRK)
 384                                flag = TTY_BREAK;
 385                        else if (sr & SR_PE)
 386                                flag = TTY_PARITY;
 387                        else if (sr & SR_FE)
 388                                flag = TTY_FRAME;
 389                        else if (sr & SR_OVR)
 390                                flag = TTY_OVERRUN;
 391                }
 392
 393                if (uart_handle_sysrq_char(port, ch))
 394                        continue;
 395
 396                if (sr & port->ignore_status_mask)
 397                        continue;
 398
 399                uart_insert_char(port, sr, SR_OVR, ch, flag);
 400        }
 401
 402        tty_flip_buffer_push(&port->state->port);
 403}
 404
 405static void sccnxp_handle_tx(struct uart_port *port)
 406{
 407        u8 sr;
 408        struct circ_buf *xmit = &port->state->xmit;
 409        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 410
 411        if (unlikely(port->x_char)) {
 412                sccnxp_port_write(port, SCCNXP_THR_REG, port->x_char);
 413                port->icount.tx++;
 414                port->x_char = 0;
 415                return;
 416        }
 417
 418        if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
 419                /* Disable TX if FIFO is empty */
 420                if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXEMT) {
 421                        sccnxp_disable_irq(port, IMR_TXRDY);
 422
 423                        /* Set direction to input */
 424                        if (s->chip->flags & SCCNXP_HAVE_IO)
 425                                sccnxp_set_bit(port, DIR_OP, 0);
 426                }
 427                return;
 428        }
 429
 430        while (!uart_circ_empty(xmit)) {
 431                sr = sccnxp_port_read(port, SCCNXP_SR_REG);
 432                if (!(sr & SR_TXRDY))
 433                        break;
 434
 435                sccnxp_port_write(port, SCCNXP_THR_REG, xmit->buf[xmit->tail]);
 436                xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 437                port->icount.tx++;
 438        }
 439
 440        if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 441                uart_write_wakeup(port);
 442}
 443
 444static void sccnxp_handle_events(struct sccnxp_port *s)
 445{
 446        int i;
 447        u8 isr;
 448
 449        do {
 450                isr = sccnxp_read(&s->port[0], SCCNXP_ISR_REG);
 451                isr &= s->imr;
 452                if (!isr)
 453                        break;
 454
 455                for (i = 0; i < s->uart.nr; i++) {
 456                        if (s->opened[i] && (isr & ISR_RXRDY(i)))
 457                                sccnxp_handle_rx(&s->port[i]);
 458                        if (s->opened[i] && (isr & ISR_TXRDY(i)))
 459                                sccnxp_handle_tx(&s->port[i]);
 460                }
 461        } while (1);
 462}
 463
 464static void sccnxp_timer(struct timer_list *t)
 465{
 466        struct sccnxp_port *s = from_timer(s, t, timer);
 467        unsigned long flags;
 468
 469        spin_lock_irqsave(&s->lock, flags);
 470        sccnxp_handle_events(s);
 471        spin_unlock_irqrestore(&s->lock, flags);
 472
 473        mod_timer(&s->timer, jiffies + usecs_to_jiffies(s->pdata.poll_time_us));
 474}
 475
 476static irqreturn_t sccnxp_ist(int irq, void *dev_id)
 477{
 478        struct sccnxp_port *s = (struct sccnxp_port *)dev_id;
 479        unsigned long flags;
 480
 481        spin_lock_irqsave(&s->lock, flags);
 482        sccnxp_handle_events(s);
 483        spin_unlock_irqrestore(&s->lock, flags);
 484
 485        return IRQ_HANDLED;
 486}
 487
 488static void sccnxp_start_tx(struct uart_port *port)
 489{
 490        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 491        unsigned long flags;
 492
 493        spin_lock_irqsave(&s->lock, flags);
 494
 495        /* Set direction to output */
 496        if (s->chip->flags & SCCNXP_HAVE_IO)
 497                sccnxp_set_bit(port, DIR_OP, 1);
 498
 499        sccnxp_enable_irq(port, IMR_TXRDY);
 500
 501        spin_unlock_irqrestore(&s->lock, flags);
 502}
 503
 504static void sccnxp_stop_tx(struct uart_port *port)
 505{
 506        /* Do nothing */
 507}
 508
 509static void sccnxp_stop_rx(struct uart_port *port)
 510{
 511        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 512        unsigned long flags;
 513
 514        spin_lock_irqsave(&s->lock, flags);
 515        sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE);
 516        spin_unlock_irqrestore(&s->lock, flags);
 517}
 518
 519static unsigned int sccnxp_tx_empty(struct uart_port *port)
 520{
 521        u8 val;
 522        unsigned long flags;
 523        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 524
 525        spin_lock_irqsave(&s->lock, flags);
 526        val = sccnxp_port_read(port, SCCNXP_SR_REG);
 527        spin_unlock_irqrestore(&s->lock, flags);
 528
 529        return (val & SR_TXEMT) ? TIOCSER_TEMT : 0;
 530}
 531
 532static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl)
 533{
 534        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 535        unsigned long flags;
 536
 537        if (!(s->chip->flags & SCCNXP_HAVE_IO))
 538                return;
 539
 540        spin_lock_irqsave(&s->lock, flags);
 541
 542        sccnxp_set_bit(port, DTR_OP, mctrl & TIOCM_DTR);
 543        sccnxp_set_bit(port, RTS_OP, mctrl & TIOCM_RTS);
 544
 545        spin_unlock_irqrestore(&s->lock, flags);
 546}
 547
 548static unsigned int sccnxp_get_mctrl(struct uart_port *port)
 549{
 550        u8 bitmask, ipr;
 551        unsigned long flags;
 552        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 553        unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
 554
 555        if (!(s->chip->flags & SCCNXP_HAVE_IO))
 556                return mctrl;
 557
 558        spin_lock_irqsave(&s->lock, flags);
 559
 560        ipr = ~sccnxp_read(port, SCCNXP_IPCR_REG);
 561
 562        if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DSR_IP)) {
 563                bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
 564                                          DSR_IP);
 565                mctrl &= ~TIOCM_DSR;
 566                mctrl |= (ipr & bitmask) ? TIOCM_DSR : 0;
 567        }
 568        if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(CTS_IP)) {
 569                bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
 570                                          CTS_IP);
 571                mctrl &= ~TIOCM_CTS;
 572                mctrl |= (ipr & bitmask) ? TIOCM_CTS : 0;
 573        }
 574        if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DCD_IP)) {
 575                bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
 576                                          DCD_IP);
 577                mctrl &= ~TIOCM_CAR;
 578                mctrl |= (ipr & bitmask) ? TIOCM_CAR : 0;
 579        }
 580        if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(RNG_IP)) {
 581                bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
 582                                          RNG_IP);
 583                mctrl &= ~TIOCM_RNG;
 584                mctrl |= (ipr & bitmask) ? TIOCM_RNG : 0;
 585        }
 586
 587        spin_unlock_irqrestore(&s->lock, flags);
 588
 589        return mctrl;
 590}
 591
 592static void sccnxp_break_ctl(struct uart_port *port, int break_state)
 593{
 594        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 595        unsigned long flags;
 596
 597        spin_lock_irqsave(&s->lock, flags);
 598        sccnxp_port_write(port, SCCNXP_CR_REG, break_state ?
 599                          CR_CMD_START_BREAK : CR_CMD_STOP_BREAK);
 600        spin_unlock_irqrestore(&s->lock, flags);
 601}
 602
 603static void sccnxp_set_termios(struct uart_port *port,
 604                               struct ktermios *termios, struct ktermios *old)
 605{
 606        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 607        unsigned long flags;
 608        u8 mr1, mr2;
 609        int baud;
 610
 611        spin_lock_irqsave(&s->lock, flags);
 612
 613        /* Mask termios capabilities we don't support */
 614        termios->c_cflag &= ~CMSPAR;
 615
 616        /* Disable RX & TX, reset break condition, status and FIFOs */
 617        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET |
 618                                               CR_RX_DISABLE | CR_TX_DISABLE);
 619        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
 620        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
 621        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
 622
 623        /* Word size */
 624        switch (termios->c_cflag & CSIZE) {
 625        case CS5:
 626                mr1 = MR1_BITS_5;
 627                break;
 628        case CS6:
 629                mr1 = MR1_BITS_6;
 630                break;
 631        case CS7:
 632                mr1 = MR1_BITS_7;
 633                break;
 634        case CS8:
 635        default:
 636                mr1 = MR1_BITS_8;
 637                break;
 638        }
 639
 640        /* Parity */
 641        if (termios->c_cflag & PARENB) {
 642                if (termios->c_cflag & PARODD)
 643                        mr1 |= MR1_PAR_ODD;
 644        } else
 645                mr1 |= MR1_PAR_NO;
 646
 647        /* Stop bits */
 648        mr2 = (termios->c_cflag & CSTOPB) ? MR2_STOP2 : MR2_STOP1;
 649
 650        /* Update desired format */
 651        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR1);
 652        sccnxp_port_write(port, SCCNXP_MR_REG, mr1);
 653        sccnxp_port_write(port, SCCNXP_MR_REG, mr2);
 654
 655        /* Set read status mask */
 656        port->read_status_mask = SR_OVR;
 657        if (termios->c_iflag & INPCK)
 658                port->read_status_mask |= SR_PE | SR_FE;
 659        if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
 660                port->read_status_mask |= SR_BRK;
 661
 662        /* Set status ignore mask */
 663        port->ignore_status_mask = 0;
 664        if (termios->c_iflag & IGNBRK)
 665                port->ignore_status_mask |= SR_BRK;
 666        if (termios->c_iflag & IGNPAR)
 667                port->ignore_status_mask |= SR_PE;
 668        if (!(termios->c_cflag & CREAD))
 669                port->ignore_status_mask |= SR_PE | SR_OVR | SR_FE | SR_BRK;
 670
 671        /* Setup baudrate */
 672        baud = uart_get_baud_rate(port, termios, old, 50,
 673                                  (s->chip->flags & SCCNXP_HAVE_MR0) ?
 674                                  230400 : 38400);
 675        baud = sccnxp_set_baud(port, baud);
 676
 677        /* Update timeout according to new baud rate */
 678        uart_update_timeout(port, termios->c_cflag, baud);
 679
 680        /* Report actual baudrate back to core */
 681        if (tty_termios_baud_rate(termios))
 682                tty_termios_encode_baud_rate(termios, baud, baud);
 683
 684        /* Enable RX & TX */
 685        sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
 686
 687        spin_unlock_irqrestore(&s->lock, flags);
 688}
 689
 690static int sccnxp_startup(struct uart_port *port)
 691{
 692        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 693        unsigned long flags;
 694
 695        spin_lock_irqsave(&s->lock, flags);
 696
 697        if (s->chip->flags & SCCNXP_HAVE_IO) {
 698                /* Outputs are controlled manually */
 699                sccnxp_write(port, SCCNXP_OPCR_REG, 0);
 700        }
 701
 702        /* Reset break condition, status and FIFOs */
 703        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET);
 704        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
 705        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
 706        sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
 707
 708        /* Enable RX & TX */
 709        sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
 710
 711        /* Enable RX interrupt */
 712        sccnxp_enable_irq(port, IMR_RXRDY);
 713
 714        s->opened[port->line] = 1;
 715
 716        spin_unlock_irqrestore(&s->lock, flags);
 717
 718        return 0;
 719}
 720
 721static void sccnxp_shutdown(struct uart_port *port)
 722{
 723        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 724        unsigned long flags;
 725
 726        spin_lock_irqsave(&s->lock, flags);
 727
 728        s->opened[port->line] = 0;
 729
 730        /* Disable interrupts */
 731        sccnxp_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
 732
 733        /* Disable TX & RX */
 734        sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE | CR_TX_DISABLE);
 735
 736        /* Leave direction to input */
 737        if (s->chip->flags & SCCNXP_HAVE_IO)
 738                sccnxp_set_bit(port, DIR_OP, 0);
 739
 740        spin_unlock_irqrestore(&s->lock, flags);
 741}
 742
 743static const char *sccnxp_type(struct uart_port *port)
 744{
 745        struct sccnxp_port *s = dev_get_drvdata(port->dev);
 746
 747        return (port->type == PORT_SC26XX) ? s->chip->name : NULL;
 748}
 749
 750static void sccnxp_release_port(struct uart_port *port)
 751{
 752        /* Do nothing */
 753}
 754
 755static int sccnxp_request_port(struct uart_port *port)
 756{
 757        /* Do nothing */
 758        return 0;
 759}
 760
 761static void sccnxp_config_port(struct uart_port *port, int flags)
 762{
 763        if (flags & UART_CONFIG_TYPE)
 764                port->type = PORT_SC26XX;
 765}
 766
 767static int sccnxp_verify_port(struct uart_port *port, struct serial_struct *s)
 768{
 769        if ((s->type == PORT_UNKNOWN) || (s->type == PORT_SC26XX))
 770                return 0;
 771        if (s->irq == port->irq)
 772                return 0;
 773
 774        return -EINVAL;
 775}
 776
 777static const struct uart_ops sccnxp_ops = {
 778        .tx_empty       = sccnxp_tx_empty,
 779        .set_mctrl      = sccnxp_set_mctrl,
 780        .get_mctrl      = sccnxp_get_mctrl,
 781        .stop_tx        = sccnxp_stop_tx,
 782        .start_tx       = sccnxp_start_tx,
 783        .stop_rx        = sccnxp_stop_rx,
 784        .break_ctl      = sccnxp_break_ctl,
 785        .startup        = sccnxp_startup,
 786        .shutdown       = sccnxp_shutdown,
 787        .set_termios    = sccnxp_set_termios,
 788        .type           = sccnxp_type,
 789        .release_port   = sccnxp_release_port,
 790        .request_port   = sccnxp_request_port,
 791        .config_port    = sccnxp_config_port,
 792        .verify_port    = sccnxp_verify_port,
 793};
 794
 795#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
 796static void sccnxp_console_putchar(struct uart_port *port, int c)
 797{
 798        int tryes = 100000;
 799
 800        while (tryes--) {
 801                if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXRDY) {
 802                        sccnxp_port_write(port, SCCNXP_THR_REG, c);
 803                        break;
 804                }
 805                barrier();
 806        }
 807}
 808
 809static void sccnxp_console_write(struct console *co, const char *c, unsigned n)
 810{
 811        struct sccnxp_port *s = (struct sccnxp_port *)co->data;
 812        struct uart_port *port = &s->port[co->index];
 813        unsigned long flags;
 814
 815        spin_lock_irqsave(&s->lock, flags);
 816        uart_console_write(port, c, n, sccnxp_console_putchar);
 817        spin_unlock_irqrestore(&s->lock, flags);
 818}
 819
 820static int sccnxp_console_setup(struct console *co, char *options)
 821{
 822        struct sccnxp_port *s = (struct sccnxp_port *)co->data;
 823        struct uart_port *port = &s->port[(co->index > 0) ? co->index : 0];
 824        int baud = 9600, bits = 8, parity = 'n', flow = 'n';
 825
 826        if (options)
 827                uart_parse_options(options, &baud, &parity, &bits, &flow);
 828
 829        return uart_set_options(port, co, baud, parity, bits, flow);
 830}
 831#endif
 832
 833static const struct platform_device_id sccnxp_id_table[] = {
 834        { .name = "sc2681",     .driver_data = (kernel_ulong_t)&sc2681, },
 835        { .name = "sc2691",     .driver_data = (kernel_ulong_t)&sc2691, },
 836        { .name = "sc2692",     .driver_data = (kernel_ulong_t)&sc2692, },
 837        { .name = "sc2891",     .driver_data = (kernel_ulong_t)&sc2891, },
 838        { .name = "sc2892",     .driver_data = (kernel_ulong_t)&sc2892, },
 839        { .name = "sc28202",    .driver_data = (kernel_ulong_t)&sc28202, },
 840        { .name = "sc68681",    .driver_data = (kernel_ulong_t)&sc68681, },
 841        { .name = "sc68692",    .driver_data = (kernel_ulong_t)&sc68692, },
 842        { }
 843};
 844MODULE_DEVICE_TABLE(platform, sccnxp_id_table);
 845
 846static int sccnxp_probe(struct platform_device *pdev)
 847{
 848        struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 849        struct sccnxp_pdata *pdata = dev_get_platdata(&pdev->dev);
 850        int i, ret, uartclk;
 851        struct sccnxp_port *s;
 852        void __iomem *membase;
 853        struct clk *clk;
 854
 855        membase = devm_ioremap_resource(&pdev->dev, res);
 856        if (IS_ERR(membase))
 857                return PTR_ERR(membase);
 858
 859        s = devm_kzalloc(&pdev->dev, sizeof(struct sccnxp_port), GFP_KERNEL);
 860        if (!s) {
 861                dev_err(&pdev->dev, "Error allocating port structure\n");
 862                return -ENOMEM;
 863        }
 864        platform_set_drvdata(pdev, s);
 865
 866        spin_lock_init(&s->lock);
 867
 868        s->chip = (struct sccnxp_chip *)pdev->id_entry->driver_data;
 869
 870        s->regulator = devm_regulator_get(&pdev->dev, "vcc");
 871        if (!IS_ERR(s->regulator)) {
 872                ret = regulator_enable(s->regulator);
 873                if (ret) {
 874                        dev_err(&pdev->dev,
 875                                "Failed to enable regulator: %i\n", ret);
 876                        return ret;
 877                }
 878        } else if (PTR_ERR(s->regulator) == -EPROBE_DEFER)
 879                return -EPROBE_DEFER;
 880
 881        clk = devm_clk_get(&pdev->dev, NULL);
 882        if (IS_ERR(clk)) {
 883                ret = PTR_ERR(clk);
 884                if (ret == -EPROBE_DEFER)
 885                        goto err_out;
 886                uartclk = 0;
 887        } else {
 888                ret = clk_prepare_enable(clk);
 889                if (ret)
 890                        goto err_out;
 891
 892                ret = devm_add_action_or_reset(&pdev->dev,
 893                                (void(*)(void *))clk_disable_unprepare,
 894                                clk);
 895                if (ret)
 896                        goto err_out;
 897
 898                uartclk = clk_get_rate(clk);
 899        }
 900
 901        if (!uartclk) {
 902                dev_notice(&pdev->dev, "Using default clock frequency\n");
 903                uartclk = s->chip->freq_std;
 904        }
 905
 906        /* Check input frequency */
 907        if ((uartclk < s->chip->freq_min) || (uartclk > s->chip->freq_max)) {
 908                dev_err(&pdev->dev, "Frequency out of bounds\n");
 909                ret = -EINVAL;
 910                goto err_out;
 911        }
 912
 913        if (pdata)
 914                memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
 915
 916        if (s->pdata.poll_time_us) {
 917                dev_info(&pdev->dev, "Using poll mode, resolution %u usecs\n",
 918                         s->pdata.poll_time_us);
 919                s->poll = 1;
 920        }
 921
 922        if (!s->poll) {
 923                s->irq = platform_get_irq(pdev, 0);
 924                if (s->irq < 0) {
 925                        dev_err(&pdev->dev, "Missing irq resource data\n");
 926                        ret = -ENXIO;
 927                        goto err_out;
 928                }
 929        }
 930
 931        s->uart.owner           = THIS_MODULE;
 932        s->uart.dev_name        = "ttySC";
 933        s->uart.major           = SCCNXP_MAJOR;
 934        s->uart.minor           = SCCNXP_MINOR;
 935        s->uart.nr              = s->chip->nr;
 936#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
 937        s->uart.cons            = &s->console;
 938        s->uart.cons->device    = uart_console_device;
 939        s->uart.cons->write     = sccnxp_console_write;
 940        s->uart.cons->setup     = sccnxp_console_setup;
 941        s->uart.cons->flags     = CON_PRINTBUFFER;
 942        s->uart.cons->index     = -1;
 943        s->uart.cons->data      = s;
 944        strcpy(s->uart.cons->name, "ttySC");
 945#endif
 946        ret = uart_register_driver(&s->uart);
 947        if (ret) {
 948                dev_err(&pdev->dev, "Registering UART driver failed\n");
 949                goto err_out;
 950        }
 951
 952        for (i = 0; i < s->uart.nr; i++) {
 953                s->port[i].line         = i;
 954                s->port[i].dev          = &pdev->dev;
 955                s->port[i].irq          = s->irq;
 956                s->port[i].type         = PORT_SC26XX;
 957                s->port[i].fifosize     = s->chip->fifosize;
 958                s->port[i].flags        = UPF_SKIP_TEST | UPF_FIXED_TYPE;
 959                s->port[i].iotype       = UPIO_MEM;
 960                s->port[i].mapbase      = res->start;
 961                s->port[i].membase      = membase;
 962                s->port[i].regshift     = s->pdata.reg_shift;
 963                s->port[i].uartclk      = uartclk;
 964                s->port[i].ops          = &sccnxp_ops;
 965                uart_add_one_port(&s->uart, &s->port[i]);
 966                /* Set direction to input */
 967                if (s->chip->flags & SCCNXP_HAVE_IO)
 968                        sccnxp_set_bit(&s->port[i], DIR_OP, 0);
 969        }
 970
 971        /* Disable interrupts */
 972        s->imr = 0;
 973        sccnxp_write(&s->port[0], SCCNXP_IMR_REG, 0);
 974
 975        if (!s->poll) {
 976                ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL,
 977                                                sccnxp_ist,
 978                                                IRQF_TRIGGER_FALLING |
 979                                                IRQF_ONESHOT,
 980                                                dev_name(&pdev->dev), s);
 981                if (!ret)
 982                        return 0;
 983
 984                dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq);
 985        } else {
 986                timer_setup(&s->timer, sccnxp_timer, 0);
 987                mod_timer(&s->timer, jiffies +
 988                          usecs_to_jiffies(s->pdata.poll_time_us));
 989                return 0;
 990        }
 991
 992        uart_unregister_driver(&s->uart);
 993err_out:
 994        if (!IS_ERR(s->regulator))
 995                regulator_disable(s->regulator);
 996
 997        return ret;
 998}
 999
1000static int sccnxp_remove(struct platform_device *pdev)
1001{
1002        int i;
1003        struct sccnxp_port *s = platform_get_drvdata(pdev);
1004
1005        if (!s->poll)
1006                devm_free_irq(&pdev->dev, s->irq, s);
1007        else
1008                del_timer_sync(&s->timer);
1009
1010        for (i = 0; i < s->uart.nr; i++)
1011                uart_remove_one_port(&s->uart, &s->port[i]);
1012
1013        uart_unregister_driver(&s->uart);
1014
1015        if (!IS_ERR(s->regulator))
1016                return regulator_disable(s->regulator);
1017
1018        return 0;
1019}
1020
1021static struct platform_driver sccnxp_uart_driver = {
1022        .driver = {
1023                .name   = SCCNXP_NAME,
1024        },
1025        .probe          = sccnxp_probe,
1026        .remove         = sccnxp_remove,
1027        .id_table       = sccnxp_id_table,
1028};
1029module_platform_driver(sccnxp_uart_driver);
1030
1031MODULE_LICENSE("GPL v2");
1032MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
1033MODULE_DESCRIPTION("SCCNXP serial driver");
1034