drivers/tty/serial/omap-serial.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Driver for OMAP-UART controller.
   4  * Based on drivers/serial/8250.c
   5  *
   6  * Copyright (C) 2010 Texas Instruments.
   7  *
   8  * Authors:
   9  *      Govindraj R     <govindraj.raja@ti.com>
  10  *      Thara Gopinath  <thara@ti.com>
  11  *
  12  * Note: This driver is made separate from 8250 driver as we cannot
  13  * over load 8250 driver with omap platform specific configuration for
  14  * features like DMA, it makes easier to implement features like DMA and
  15  * hardware flow control and software flow control configuration with
  16  * this driver as required for the omap-platform.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/console.h>
  22 #include <linux/serial.h>
  23 #include <linux/serial_reg.h>
  24 #include <linux/delay.h>
  25 #include <linux/slab.h>
  26 #include <linux/tty.h>
  27 #include <linux/tty_flip.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/io.h>
  30 #include <linux/clk.h>
  31 #include <linux/serial_core.h>
  32 #include <linux/irq.h>
  33 #include <linux/pm_runtime.h>
  34 #include <linux/pm_wakeirq.h>
  35 #include <linux/of.h>
  36 #include <linux/of_irq.h>
  37 #include <linux/gpio/consumer.h>
  38 #include <linux/platform_data/serial-omap.h>
  39
  40 #define OMAP_MAX_HSUART_PORTS   10
  41
  42 #define UART_BUILD_REVISION(x, y)       (((x) << 8) | (y))
  43
  44 #define OMAP_UART_REV_42 0x0402
  45 #define OMAP_UART_REV_46 0x0406
  46 #define OMAP_UART_REV_52 0x0502
  47 #define OMAP_UART_REV_63 0x0603
  48
  49 #define OMAP_UART_TX_WAKEUP_EN          BIT(7)
  50
  51 /* Feature flags */
  52 #define OMAP_UART_WER_HAS_TX_WAKEUP     BIT(0)
  53
  54 #define UART_ERRATA_i202_MDR1_ACCESS    BIT(0)
  55 #define UART_ERRATA_i291_DMA_FORCEIDLE  BIT(1)
  56
  57 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
  58
  59 /* SCR register bitmasks */
  60 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK               (1 << 7)
  61 #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK               (1 << 6)
  62 #define OMAP_UART_SCR_TX_EMPTY                  (1 << 3)
  63
  64 /* FCR register bitmasks */
  65 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK                 (0x3 << 6)
  66 #define OMAP_UART_FCR_TX_FIFO_TRIG_MASK                 (0x3 << 4)
  67
  68 /* MVR register bitmasks */
  69 #define OMAP_UART_MVR_SCHEME_SHIFT      30
  70
  71 #define OMAP_UART_LEGACY_MVR_MAJ_MASK   0xf0
  72 #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT  4
  73 #define OMAP_UART_LEGACY_MVR_MIN_MASK   0x0f
  74
  75 #define OMAP_UART_MVR_MAJ_MASK          0x700
  76 #define OMAP_UART_MVR_MAJ_SHIFT         8
  77 #define OMAP_UART_MVR_MIN_MASK          0x3f
  78
  79 #define OMAP_UART_DMA_CH_FREE   -1
  80
  81 #define MSR_SAVE_FLAGS          UART_MSR_ANY_DELTA
  82 #define OMAP_MODE13X_SPEED      230400
  83
  84 /* WER = 0x7F
  85  * Enable module level wakeup in WER reg
  86  */
  87 #define OMAP_UART_WER_MOD_WKUP  0x7F
  88
  89 /* Enable XON/XOFF flow control on output */
  90 #define OMAP_UART_SW_TX         0x08
  91
  92 /* Enable XON/XOFF flow control on input */
  93 #define OMAP_UART_SW_RX         0x02
  94
  95 #define OMAP_UART_SW_CLR        0xF0
  96
  97 #define OMAP_UART_TCR_TRIG      0x0F
  98
  99 struct uart_omap_dma {
 100         u8                      uart_dma_tx;
 101         u8                      uart_dma_rx;
 102         int                     rx_dma_channel;
 103         int                     tx_dma_channel;
 104         dma_addr_t              rx_buf_dma_phys;
 105         dma_addr_t              tx_buf_dma_phys;
 106         unsigned int            uart_base;
 107         /*
 108          * Buffer for rx dma. It is not required for tx because the buffer
 109          * comes from port structure.
 110          */
 111         unsigned char           *rx_buf;
 112         unsigned int            prev_rx_dma_pos;
 113         int                     tx_buf_size;
 114         int                     tx_dma_used;
 115         int                     rx_dma_used;
 116         spinlock_t              tx_lock;
 117         spinlock_t              rx_lock;
 118         /* timer to poll activity on rx dma */
 119         struct timer_list       rx_timer;
 120         unsigned int            rx_buf_size;
 121         unsigned int            rx_poll_rate;
 122         unsigned int            rx_timeout;
 123 };
 124
 125 struct uart_omap_port {
 126         struct uart_port        port;
 127         struct uart_omap_dma    uart_dma;
 128         struct device           *dev;
 129         int                     wakeirq;
 130
 131         unsigned char           ier;
 132         unsigned char           lcr;
 133         unsigned char           mcr;
 134         unsigned char           fcr;
 135         unsigned char           efr;
 136         unsigned char           dll;
 137         unsigned char           dlh;
 138         unsigned char           mdr1;
 139         unsigned char           scr;
 140         unsigned char           wer;
 141
 142         int                     use_dma;
 143         /*
 144          * Some bits in registers are cleared on a read, so they must
 145          * be saved whenever the register is read, but the bits will not
 146          * be immediately processed.
 147          */
 148         unsigned int            lsr_break_flag;
 149         unsigned char           msr_saved_flags;
 150         char                    name[20];
 151         unsigned long           port_activity;
 152         int                     context_loss_cnt;
 153         u32                     errata;
 154         u32                     features;
 155
 156         struct gpio_desc        *rts_gpiod;
 157
 158         struct pm_qos_request   pm_qos_request;
 159         u32                     latency;
 160         u32                     calc_latency;
 161         struct work_struct      qos_work;
 162         bool                    is_suspending;
 163
 164         unsigned int            rs485_tx_filter_count;
 165 };
 166
 167 #define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
 168
 169 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
 170
 171 /* Forward declaration of functions */
 172 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
 173
 174 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
 175 {
 176         offset <<= up->port.regshift;
 177         return readw(up->port.membase + offset);
 178 }
 179
 180 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
 181 {
 182         offset <<= up->port.regshift;
 183         writew(value, up->port.membase + offset);
 184 }
 185
 186 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
 187 {
 188         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
 189         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 190                        UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 191         serial_out(up, UART_FCR, 0);
 192 }
 193
 194 #ifdef CONFIG_PM
 195 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
 196 {
 197         struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 198
 199         if (!pdata || !pdata->get_context_loss_count)
 200                 return -EINVAL;
 201
 202         return pdata->get_context_loss_count(up->dev);
 203 }
 204
 205 /* REVISIT: Remove this when omap3 boots in device tree only mode */
 206 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
 207 {
 208         struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 209
 210         if (!pdata || !pdata->enable_wakeup)
 211                 return;
 212
 213         pdata->enable_wakeup(up->dev, enable);
 214 }
 215 #endif /* CONFIG_PM */
 216
 217 /*
 218  * Calculate the absolute difference between the desired and actual baud
 219  * rate for the given mode.
 220  */
 221 static inline int calculate_baud_abs_diff(struct uart_port *port,
 222                                 unsigned int baud, unsigned int mode)
 223 {
 224         unsigned int n = port->uartclk / (mode * baud);
 225
 226         if (n == 0)
 227                 n = 1;
 228
 229         return abs_diff(baud, port->uartclk / (mode * n));
 230 }
 231
 232 /*
 233  * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
 234  * @port: uart port info
 235  * @baud: baudrate for which mode needs to be determined
 236  *
 237  * Returns true if baud rate is MODE16X and false if MODE13X
 238  * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
 239  * and Error Rates" determines modes not for all common baud rates.
 240  * E.g. for 1000000 baud rate mode must be 16x, but according to that
 241  * table it's determined as 13x.
 242  */
 243 static bool
 244 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
 245 {
 246         int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
 247         int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
 248
 249         return (abs_diff_13 >= abs_diff_16);
 250 }
 251
 252 /*
 253  * serial_omap_get_divisor - calculate divisor value
 254  * @port: uart port info
 255  * @baud: baudrate for which divisor needs to be calculated.
 256  */
 257 static unsigned int
 258 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
 259 {
 260         unsigned int mode;
 261
 262         if (!serial_omap_baud_is_mode16(port, baud))
 263                 mode = 13;
 264         else
 265                 mode = 16;
 266         return port->uartclk/(mode * baud);
 267 }
 268
 269 static void serial_omap_enable_ms(struct uart_port *port)
 270 {
 271         struct uart_omap_port *up = to_uart_omap_port(port);
 272
 273         dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
 274
 275         up->ier |= UART_IER_MSI;
 276         serial_out(up, UART_IER, up->ier);
 277 }
 278
 279 static void serial_omap_stop_tx(struct uart_port *port)
 280 {
 281         struct uart_omap_port *up = to_uart_omap_port(port);
 282         int res;
 283
 284         /* Handle RS-485 */
 285         if (port->rs485.flags & SER_RS485_ENABLED) {
 286                 if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
 287                         /* THR interrupt is fired when both TX FIFO and TX
 288                          * shift register are empty. This means there's nothing
 289                          * left to transmit now, so make sure the THR interrupt
 290                          * is fired when TX FIFO is below the trigger level,
 291                          * disable THR interrupts and toggle the RS-485 GPIO
 292                          * data direction pin if needed.
 293                          */
 294                         up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
 295                         serial_out(up, UART_OMAP_SCR, up->scr);
 296                         res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
 297                                 1 : 0;
 298                         if (gpiod_get_value(up->rts_gpiod) != res) {
 299                                 if (port->rs485.delay_rts_after_send > 0)
 300                                         mdelay(
 301                                         port->rs485.delay_rts_after_send);
 302                                 gpiod_set_value(up->rts_gpiod, res);
 303                         }
 304                 } else {
 305                         /* We're asked to stop, but there's still stuff in the
 306                          * UART FIFO, so make sure the THR interrupt is fired
 307                          * when both TX FIFO and TX shift register are empty.
 308                          * The next THR interrupt (if no transmission is started
 309                          * in the meantime) will indicate the end of a
 310                          * transmission. Therefore we _don't_ disable THR
 311                          * interrupts in this situation.
 312                          */
 313                         up->scr |= OMAP_UART_SCR_TX_EMPTY;
 314                         serial_out(up, UART_OMAP_SCR, up->scr);
 315                         return;
 316                 }
 317         }
 318
 319         if (up->ier & UART_IER_THRI) {
 320                 up->ier &= ~UART_IER_THRI;
 321                 serial_out(up, UART_IER, up->ier);
 322         }
 323 }
 324
 325 static void serial_omap_stop_rx(struct uart_port *port)
 326 {
 327         struct uart_omap_port *up = to_uart_omap_port(port);
 328
 329         up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 330         up->port.read_status_mask &= ~UART_LSR_DR;
 331         serial_out(up, UART_IER, up->ier);
 332 }
 333
 334 static void serial_omap_put_char(struct uart_omap_port *up, unsigned char ch)
 335 {
 336         serial_out(up, UART_TX, ch);
 337
 338         if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
 339                         !(up->port.rs485.flags & SER_RS485_RX_DURING_TX))
 340                 up->rs485_tx_filter_count++;
 341 }
 342
 343 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
 344 {
 345         u8 ch;
 346
 347         uart_port_tx_limited(&up->port, ch, up->port.fifosize / 4,
 348                 true,
 349                 serial_omap_put_char(up, ch),
 350                 ({}));
 351 }
 352
 353 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
 354 {
 355         if (!(up->ier & UART_IER_THRI)) {
 356                 up->ier |= UART_IER_THRI;
 357                 serial_out(up, UART_IER, up->ier);
 358         }
 359 }
 360
 361 static void serial_omap_start_tx(struct uart_port *port)
 362 {
 363         struct uart_omap_port *up = to_uart_omap_port(port);
 364         int res;
 365
 366         /* Handle RS-485 */
 367         if (port->rs485.flags & SER_RS485_ENABLED) {
 368                 /* Fire THR interrupts when FIFO is below trigger level */
 369                 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
 370                 serial_out(up, UART_OMAP_SCR, up->scr);
 371
 372                 /* if rts not already enabled */
 373                 res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
 374                 if (gpiod_get_value(up->rts_gpiod) != res) {
 375                         gpiod_set_value(up->rts_gpiod, res);
 376                         if (port->rs485.delay_rts_before_send > 0)
 377                                 mdelay(port->rs485.delay_rts_before_send);
 378                 }
 379         }
 380
 381         if ((port->rs485.flags & SER_RS485_ENABLED) &&
 382             !(port->rs485.flags & SER_RS485_RX_DURING_TX))
 383                 up->rs485_tx_filter_count = 0;
 384
 385         serial_omap_enable_ier_thri(up);
 386 }
 387
 388 static void serial_omap_throttle(struct uart_port *port)
 389 {
 390         struct uart_omap_port *up = to_uart_omap_port(port);
 391         unsigned long flags;
 392
 393         uart_port_lock_irqsave(&up->port, &flags);
 394         up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 395         serial_out(up, UART_IER, up->ier);
 396         uart_port_unlock_irqrestore(&up->port, flags);
 397 }
 398
 399 static void serial_omap_unthrottle(struct uart_port *port)
 400 {
 401         struct uart_omap_port *up = to_uart_omap_port(port);
 402         unsigned long flags;
 403
 404         uart_port_lock_irqsave(&up->port, &flags);
 405         up->ier |= UART_IER_RLSI | UART_IER_RDI;
 406         serial_out(up, UART_IER, up->ier);
 407         uart_port_unlock_irqrestore(&up->port, flags);
 408 }
 409
 410 static unsigned int check_modem_status(struct uart_omap_port *up)
 411 {
 412         unsigned int status;
 413
 414         status = serial_in(up, UART_MSR);
 415         status |= up->msr_saved_flags;
 416         up->msr_saved_flags = 0;
 417         if ((status & UART_MSR_ANY_DELTA) == 0)
 418                 return status;
 419
 420         if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
 421             up->port.state != NULL) {
 422                 if (status & UART_MSR_TERI)
 423                         up->port.icount.rng++;
 424                 if (status & UART_MSR_DDSR)
 425                         up->port.icount.dsr++;
 426                 if (status & UART_MSR_DDCD)
 427                         uart_handle_dcd_change
 428                                 (&up->port, status & UART_MSR_DCD);
 429                 if (status & UART_MSR_DCTS)
 430                         uart_handle_cts_change
 431                                 (&up->port, status & UART_MSR_CTS);
 432                 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 433         }
 434
 435         return status;
 436 }
 437
 438 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
 439 {
 440         u8 flag;
 441
 442         /*
 443          * Read one data character out to avoid stalling the receiver according
 444          * to the table 23-246 of the omap4 TRM.
 445          */
 446         if (likely(lsr & UART_LSR_DR)) {
 447                 serial_in(up, UART_RX);
 448                 if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
 449                     !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) &&
 450                     up->rs485_tx_filter_count)
 451                         up->rs485_tx_filter_count--;
 452         }
 453
 454         up->port.icount.rx++;
 455         flag = TTY_NORMAL;
 456
 457         if (lsr & UART_LSR_BI) {
 458                 flag = TTY_BREAK;
 459                 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
 460                 up->port.icount.brk++;
 461                 /*
 462                  * We do the SysRQ and SAK checking
 463                  * here because otherwise the break
 464                  * may get masked by ignore_status_mask
 465                  * or read_status_mask.
 466                  */
 467                 if (uart_handle_break(&up->port))
 468                         return;
 469
 470         }
 471
 472         if (lsr & UART_LSR_PE) {
 473                 flag = TTY_PARITY;
 474                 up->port.icount.parity++;
 475         }
 476
 477         if (lsr & UART_LSR_FE) {
 478                 flag = TTY_FRAME;
 479                 up->port.icount.frame++;
 480         }
 481
 482         if (lsr & UART_LSR_OE)
 483                 up->port.icount.overrun++;
 484
 485 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
 486         if (up->port.line == up->port.cons->index) {
 487                 /* Recover the break flag from console xmit */
 488                 lsr |= up->lsr_break_flag;
 489         }
 490 #endif
 491         uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
 492 }
 493
 494 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
 495 {
 496         u8 ch;
 497
 498         if (!(lsr & UART_LSR_DR))
 499                 return;
 500
 501         ch = serial_in(up, UART_RX);
 502         if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
 503             !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) &&
 504             up->rs485_tx_filter_count) {
 505                 up->rs485_tx_filter_count--;
 506                 return;
 507         }
 508
 509         up->port.icount.rx++;
 510
 511         if (uart_prepare_sysrq_char(&up->port, ch))
 512                 return;
 513
 514         uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, TTY_NORMAL);
 515 }
 516
 517 /**
 518  * serial_omap_irq() - This handles the interrupt from one port
 519  * @irq: uart port irq number
 520  * @dev_id: uart port info
 521  */
 522 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 523 {
 524         struct uart_omap_port *up = dev_id;
 525         unsigned int iir, lsr;
 526         unsigned int type;
 527         irqreturn_t ret = IRQ_NONE;
 528         int max_count = 256;
 529
 530         uart_port_lock(&up->port);
 531
 532         do {
 533                 iir = serial_in(up, UART_IIR);
 534                 if (iir & UART_IIR_NO_INT)
 535                         break;
 536
 537                 ret = IRQ_HANDLED;
 538                 lsr = serial_in(up, UART_LSR);
 539
 540                 /* extract IRQ type from IIR register */
 541                 type = iir & 0x3e;
 542
 543                 switch (type) {
 544                 case UART_IIR_MSI:
 545                         check_modem_status(up);
 546                         break;
 547                 case UART_IIR_THRI:
 548                         transmit_chars(up, lsr);
 549                         break;
 550                 case UART_IIR_RX_TIMEOUT:
 551                 case UART_IIR_RDI:
 552                         serial_omap_rdi(up, lsr);
 553                         break;
 554                 case UART_IIR_RLSI:
 555                         serial_omap_rlsi(up, lsr);
 556                         break;
 557                 case UART_IIR_CTS_RTS_DSR:
 558                         /* simply try again */
 559                         break;
 560                 case UART_IIR_XOFF:
 561                 default:
 562                         break;
 563                 }
 564         } while (max_count--);
 565
 566         uart_unlock_and_check_sysrq(&up->port);
 567
 568         tty_flip_buffer_push(&up->port.state->port);
 569
 570         up->port_activity = jiffies;
 571
 572         return ret;
 573 }
 574
 575 static unsigned int serial_omap_tx_empty(struct uart_port *port)
 576 {
 577         struct uart_omap_port *up = to_uart_omap_port(port);
 578         unsigned long flags;
 579         unsigned int ret = 0;
 580
 581         dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
 582         uart_port_lock_irqsave(&up->port, &flags);
 583         ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 584         uart_port_unlock_irqrestore(&up->port, flags);
 585
 586         return ret;
 587 }
 588
 589 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
 590 {
 591         struct uart_omap_port *up = to_uart_omap_port(port);
 592         unsigned int status;
 593         unsigned int ret = 0;
 594
 595         status = check_modem_status(up);
 596
 597         dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
 598
 599         if (status & UART_MSR_DCD)
 600                 ret |= TIOCM_CAR;
 601         if (status & UART_MSR_RI)
 602                 ret |= TIOCM_RNG;
 603         if (status & UART_MSR_DSR)
 604                 ret |= TIOCM_DSR;
 605         if (status & UART_MSR_CTS)
 606                 ret |= TIOCM_CTS;
 607         return ret;
 608 }
 609
 610 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 611 {
 612         struct uart_omap_port *up = to_uart_omap_port(port);
 613         unsigned char mcr = 0, old_mcr, lcr;
 614
 615         dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
 616         if (mctrl & TIOCM_RTS)
 617                 mcr |= UART_MCR_RTS;
 618         if (mctrl & TIOCM_DTR)
 619                 mcr |= UART_MCR_DTR;
 620         if (mctrl & TIOCM_OUT1)
 621                 mcr |= UART_MCR_OUT1;
 622         if (mctrl & TIOCM_OUT2)
 623                 mcr |= UART_MCR_OUT2;
 624         if (mctrl & TIOCM_LOOP)
 625                 mcr |= UART_MCR_LOOP;
 626
 627         old_mcr = serial_in(up, UART_MCR);
 628         old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
 629                      UART_MCR_DTR | UART_MCR_RTS);
 630         up->mcr = old_mcr | mcr;
 631         serial_out(up, UART_MCR, up->mcr);
 632
 633         /* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
 634         lcr = serial_in(up, UART_LCR);
 635         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 636         if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
 637                 up->efr |= UART_EFR_RTS;
 638         else
 639                 up->efr &= ~UART_EFR_RTS;
 640         serial_out(up, UART_EFR, up->efr);
 641         serial_out(up, UART_LCR, lcr);
 642 }
 643
 644 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
 645 {
 646         struct uart_omap_port *up = to_uart_omap_port(port);
 647         unsigned long flags;
 648
 649         dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
 650         uart_port_lock_irqsave(&up->port, &flags);
 651         if (break_state == -1)
 652                 up->lcr |= UART_LCR_SBC;
 653         else
 654                 up->lcr &= ~UART_LCR_SBC;
 655         serial_out(up, UART_LCR, up->lcr);
 656         uart_port_unlock_irqrestore(&up->port, flags);
 657 }
 658
 659 static int serial_omap_startup(struct uart_port *port)
 660 {
 661         struct uart_omap_port *up = to_uart_omap_port(port);
 662         unsigned long flags;
 663         int retval;
 664
 665         /*
 666          * Allocate the IRQ
 667          */
 668         retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
 669                                 up->name, up);
 670         if (retval)
 671                 return retval;
 672
 673         /* Optional wake-up IRQ */
 674         if (up->wakeirq) {
 675                 retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
 676                 if (retval) {
 677                         free_irq(up->port.irq, up);
 678                         return retval;
 679                 }
 680         }
 681
 682         dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
 683
 684         pm_runtime_get_sync(up->dev);
 685         /*
 686          * Clear the FIFO buffers and disable them.
 687          * (they will be reenabled in set_termios())
 688          */
 689         serial_omap_clear_fifos(up);
 690
 691         /*
 692          * Clear the interrupt registers.
 693          */
 694         (void) serial_in(up, UART_LSR);
 695         if (serial_in(up, UART_LSR) & UART_LSR_DR)
 696                 (void) serial_in(up, UART_RX);
 697         (void) serial_in(up, UART_IIR);
 698         (void) serial_in(up, UART_MSR);
 699
 700         /*
 701          * Now, initialize the UART
 702          */
 703         serial_out(up, UART_LCR, UART_LCR_WLEN8);
 704         uart_port_lock_irqsave(&up->port, &flags);
 705         /*
 706          * Most PC uarts need OUT2 raised to enable interrupts.
 707          */
 708         up->port.mctrl |= TIOCM_OUT2;
 709         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 710         uart_port_unlock_irqrestore(&up->port, flags);
 711
 712         up->msr_saved_flags = 0;
 713         /*
 714          * Finally, enable interrupts. Note: Modem status interrupts
 715          * are set via set_termios(), which will be occurring imminently
 716          * anyway, so we don't enable them here.
 717          */
 718         up->ier = UART_IER_RLSI | UART_IER_RDI;
 719         serial_out(up, UART_IER, up->ier);
 720
 721         /* Enable module level wake up */
 722         up->wer = OMAP_UART_WER_MOD_WKUP;
 723         if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
 724                 up->wer |= OMAP_UART_TX_WAKEUP_EN;
 725
 726         serial_out(up, UART_OMAP_WER, up->wer);
 727
 728         up->port_activity = jiffies;
 729         return 0;
 730 }
 731
 732 static void serial_omap_shutdown(struct uart_port *port)
 733 {
 734         struct uart_omap_port *up = to_uart_omap_port(port);
 735         unsigned long flags;
 736
 737         dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
 738
 739         /*
 740          * Disable interrupts from this port
 741          */
 742         up->ier = 0;
 743         serial_out(up, UART_IER, 0);
 744
 745         uart_port_lock_irqsave(&up->port, &flags);
 746         up->port.mctrl &= ~TIOCM_OUT2;
 747         serial_omap_set_mctrl(&up->port, up->port.mctrl);
 748         uart_port_unlock_irqrestore(&up->port, flags);
 749
 750         /*
 751          * Disable break condition and FIFOs
 752          */
 753         serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 754         serial_omap_clear_fifos(up);
 755
 756         /*
 757          * Read data port to reset things, and then free the irq
 758          */
 759         if (serial_in(up, UART_LSR) & UART_LSR_DR)
 760                 (void) serial_in(up, UART_RX);
 761
 762         pm_runtime_put_sync(up->dev);
 763         free_irq(up->port.irq, up);
 764         dev_pm_clear_wake_irq(up->dev);
 765 }
 766
 767 static void serial_omap_uart_qos_work(struct work_struct *work)
 768 {
 769         struct uart_omap_port *up = container_of(work, struct uart_omap_port,
 770                                                 qos_work);
 771
 772         cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
 773 }
 774
 775 static void
 776 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 777                         const struct ktermios *old)
 778 {
 779         struct uart_omap_port *up = to_uart_omap_port(port);
 780         unsigned char cval = 0;
 781         unsigned long flags;
 782         unsigned int baud, quot;
 783
 784         cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));
 785
 786         if (termios->c_cflag & CSTOPB)
 787                 cval |= UART_LCR_STOP;
 788         if (termios->c_cflag & PARENB)
 789                 cval |= UART_LCR_PARITY;
 790         if (!(termios->c_cflag & PARODD))
 791                 cval |= UART_LCR_EPAR;
 792         if (termios->c_cflag & CMSPAR)
 793                 cval |= UART_LCR_SPAR;
 794
 795         /*
 796          * Ask the core to calculate the divisor for us.
 797          */
 798
 799         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
 800         quot = serial_omap_get_divisor(port, baud);
 801
 802         /* calculate wakeup latency constraint */
 803         up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
 804         up->latency = up->calc_latency;
 805         schedule_work(&up->qos_work);
 806
 807         up->dll = quot & 0xff;
 808         up->dlh = quot >> 8;
 809         up->mdr1 = UART_OMAP_MDR1_DISABLE;
 810
 811         up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
 812                         UART_FCR_ENABLE_FIFO;
 813
 814         /*
 815          * Ok, we're now changing the port state. Do it with
 816          * interrupts disabled.
 817          */
 818         uart_port_lock_irqsave(&up->port, &flags);
 819
 820         /*
 821          * Update the per-port timeout.
 822          */
 823         uart_update_timeout(port, termios->c_cflag, baud);
 824
 825         up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 826         if (termios->c_iflag & INPCK)
 827                 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 828         if (termios->c_iflag & (BRKINT | PARMRK))
 829                 up->port.read_status_mask |= UART_LSR_BI;
 830
 831         /*
 832          * Characters to ignore
 833          */
 834         up->port.ignore_status_mask = 0;
 835         if (termios->c_iflag & IGNPAR)
 836                 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 837         if (termios->c_iflag & IGNBRK) {
 838                 up->port.ignore_status_mask |= UART_LSR_BI;
 839                 /*
 840                  * If we're ignoring parity and break indicators,
 841                  * ignore overruns too (for real raw support).
 842                  */
 843                 if (termios->c_iflag & IGNPAR)
 844                         up->port.ignore_status_mask |= UART_LSR_OE;
 845         }
 846
 847         /*
 848          * ignore all characters if CREAD is not set
 849          */
 850         if ((termios->c_cflag & CREAD) == 0)
 851                 up->port.ignore_status_mask |= UART_LSR_DR;
 852
 853         /*
 854          * Modem status interrupts
 855          */
 856         up->ier &= ~UART_IER_MSI;
 857         if (UART_ENABLE_MS(&up->port, termios->c_cflag))
 858                 up->ier |= UART_IER_MSI;
 859         serial_out(up, UART_IER, up->ier);
 860         serial_out(up, UART_LCR, cval);         /* reset DLAB */
 861         up->lcr = cval;
 862         up->scr = 0;
 863
 864         /* FIFOs and DMA Settings */
 865
 866         /* FCR can be changed only when the
 867          * baud clock is not running
 868          * DLL_REG and DLH_REG set to 0.
 869          */
 870         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 871         serial_out(up, UART_DLL, 0);
 872         serial_out(up, UART_DLM, 0);
 873         serial_out(up, UART_LCR, 0);
 874
 875         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 876
 877         up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
 878         up->efr &= ~UART_EFR_SCD;
 879         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 880
 881         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 882         up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
 883         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 884         /* FIFO ENABLE, DMA MODE */
 885
 886         up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
 887         /*
 888          * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
 889          * sets Enables the granularity of 1 for TRIGGER RX
 890          * level. Along with setting RX FIFO trigger level
 891          * to 1 (as noted below, 16 characters) and TLR[3:0]
 892          * to zero this will result RX FIFO threshold level
 893          * to 1 character, instead of 16 as noted in comment
 894          * below.
 895          */
 896
 897         /* Set receive FIFO threshold to 16 characters and
 898          * transmit FIFO threshold to 32 spaces
 899          */
 900         up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
 901         up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
 902         up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
 903                 UART_FCR_ENABLE_FIFO;
 904
 905         serial_out(up, UART_FCR, up->fcr);
 906         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 907
 908         serial_out(up, UART_OMAP_SCR, up->scr);
 909
 910         /* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
 911         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 912         serial_out(up, UART_MCR, up->mcr);
 913         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 914         serial_out(up, UART_EFR, up->efr);
 915         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 916
 917         /* Protocol, Baud Rate, and Interrupt Settings */
 918
 919         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
 920                 serial_omap_mdr1_errataset(up, up->mdr1);
 921         else
 922                 serial_out(up, UART_OMAP_MDR1, up->mdr1);
 923
 924         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 925         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 926
 927         serial_out(up, UART_LCR, 0);
 928         serial_out(up, UART_IER, 0);
 929         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 930
 931         serial_out(up, UART_DLL, up->dll);      /* LS of divisor */
 932         serial_out(up, UART_DLM, up->dlh);      /* MS of divisor */
 933
 934         serial_out(up, UART_LCR, 0);
 935         serial_out(up, UART_IER, up->ier);
 936         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 937
 938         serial_out(up, UART_EFR, up->efr);
 939         serial_out(up, UART_LCR, cval);
 940
 941         if (!serial_omap_baud_is_mode16(port, baud))
 942                 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
 943         else
 944                 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
 945
 946         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
 947                 serial_omap_mdr1_errataset(up, up->mdr1);
 948         else
 949                 serial_out(up, UART_OMAP_MDR1, up->mdr1);
 950
 951         /* Configure flow control */
 952         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 953
 954         /* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
 955         serial_out(up, UART_XON1, termios->c_cc[VSTART]);
 956         serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
 957
 958         /* Enable access to TCR/TLR */
 959         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 960         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 961         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 962
 963         serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
 964
 965         up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
 966
 967         if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
 968                 /* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
 969                 up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
 970                 up->efr |= UART_EFR_CTS;
 971         } else {
 972                 /* Disable AUTORTS and AUTOCTS */
 973                 up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
 974         }
 975
 976         if (up->port.flags & UPF_SOFT_FLOW) {
 977                 /* clear SW control mode bits */
 978                 up->efr &= OMAP_UART_SW_CLR;
 979
 980                 /*
 981                  * IXON Flag:
 982                  * Enable XON/XOFF flow control on input.
 983                  * Receiver compares XON1, XOFF1.
 984                  */
 985                 if (termios->c_iflag & IXON)
 986                         up->efr |= OMAP_UART_SW_RX;
 987
 988                 /*
 989                  * IXOFF Flag:
 990                  * Enable XON/XOFF flow control on output.
 991                  * Transmit XON1, XOFF1
 992                  */
 993                 if (termios->c_iflag & IXOFF) {
 994                         up->port.status |= UPSTAT_AUTOXOFF;
 995                         up->efr |= OMAP_UART_SW_TX;
 996                 }
 997
 998                 /*
 999                  * IXANY Flag:
1000                  * Enable any character to restart output.
1001                  * Operation resumes after receiving any
1002                  * character after recognition of the XOFF character
1003                  */
1004                 if (termios->c_iflag & IXANY)
1005                         up->mcr |= UART_MCR_XONANY;
1006                 else
1007                         up->mcr &= ~UART_MCR_XONANY;
1008         }
1009         serial_out(up, UART_MCR, up->mcr);
1010         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1011         serial_out(up, UART_EFR, up->efr);
1012         serial_out(up, UART_LCR, up->lcr);
1013
1014         serial_omap_set_mctrl(&up->port, up->port.mctrl);
1015
1016         uart_port_unlock_irqrestore(&up->port, flags);
1017         dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1018 }
1019
1020 static void
1021 serial_omap_pm(struct uart_port *port, unsigned int state,
1022                unsigned int oldstate)
1023 {
1024         struct uart_omap_port *up = to_uart_omap_port(port);
1025         unsigned char efr;
1026
1027         dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1028
1029         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1030         efr = serial_in(up, UART_EFR);
1031         serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1032         serial_out(up, UART_LCR, 0);
1033
1034         serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1035         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1036         serial_out(up, UART_EFR, efr);
1037         serial_out(up, UART_LCR, 0);
1038 }
1039
1040 static void serial_omap_release_port(struct uart_port *port)
1041 {
1042         dev_dbg(port->dev, "serial_omap_release_port+\n");
1043 }
1044
1045 static int serial_omap_request_port(struct uart_port *port)
1046 {
1047         dev_dbg(port->dev, "serial_omap_request_port+\n");
1048         return 0;
1049 }
1050
1051 static void serial_omap_config_port(struct uart_port *port, int flags)
1052 {
1053         struct uart_omap_port *up = to_uart_omap_port(port);
1054
1055         dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1056                                                         up->port.line);
1057         up->port.type = PORT_OMAP;
1058         up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1059 }
1060
1061 static int
1062 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1063 {
1064         /* we don't want the core code to modify any port params */
1065         dev_dbg(port->dev, "serial_omap_verify_port+\n");
1066         return -EINVAL;
1067 }
1068
1069 static const char *
1070 serial_omap_type(struct uart_port *port)
1071 {
1072         struct uart_omap_port *up = to_uart_omap_port(port);
1073
1074         dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1075         return up->name;
1076 }
1077
1078 static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1079 {
1080         unsigned int status, tmout = 10000;
1081
1082         /* Wait up to 10ms for the character(s) to be sent. */
1083         do {
1084                 status = serial_in(up, UART_LSR);
1085
1086                 if (status & UART_LSR_BI)
1087                         up->lsr_break_flag = UART_LSR_BI;
1088
1089                 if (--tmout == 0)
1090                         break;
1091                 udelay(1);
1092         } while (!uart_lsr_tx_empty(status));
1093
1094         /* Wait up to 1s for flow control if necessary */
1095         if (up->port.flags & UPF_CONS_FLOW) {
1096                 tmout = 1000000;
1097                 for (tmout = 1000000; tmout; tmout--) {
1098                         unsigned int msr = serial_in(up, UART_MSR);
1099
1100                         up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1101                         if (msr & UART_MSR_CTS)
1102                                 break;
1103
1104                         udelay(1);
1105                 }
1106         }
1107 }
1108
1109 #ifdef CONFIG_CONSOLE_POLL
1110
1111 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1112 {
1113         struct uart_omap_port *up = to_uart_omap_port(port);
1114
1115         wait_for_xmitr(up);
1116         serial_out(up, UART_TX, ch);
1117 }
1118
1119 static int serial_omap_poll_get_char(struct uart_port *port)
1120 {
1121         struct uart_omap_port *up = to_uart_omap_port(port);
1122         unsigned int status;
1123
1124         status = serial_in(up, UART_LSR);
1125         if (!(status & UART_LSR_DR)) {
1126                 status = NO_POLL_CHAR;
1127                 goto out;
1128         }
1129
1130         status = serial_in(up, UART_RX);
1131
1132 out:
1133         return status;
1134 }
1135
1136 #endif /* CONFIG_CONSOLE_POLL */
1137
1138 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1139
1140 #ifdef CONFIG_SERIAL_EARLYCON
1141 static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1142 {
1143         offset <<= port->regshift;
1144         return readw(port->membase + offset);
1145 }
1146
1147 static void omap_serial_early_out(struct uart_port *port, int offset,
1148                                   int value)
1149 {
1150         offset <<= port->regshift;
1151         writew(value, port->membase + offset);
1152 }
1153
1154 static void omap_serial_early_putc(struct uart_port *port, unsigned char c)
1155 {
1156         unsigned int status;
1157
1158         for (;;) {
1159                 status = omap_serial_early_in(port, UART_LSR);
1160                 if (uart_lsr_tx_empty(status))
1161                         break;
1162                 cpu_relax();
1163         }
1164         omap_serial_early_out(port, UART_TX, c);
1165 }
1166
1167 static void early_omap_serial_write(struct console *console, const char *s,
1168                                     unsigned int count)
1169 {
1170         struct earlycon_device *device = console->data;
1171         struct uart_port *port = &device->port;
1172
1173         uart_console_write(port, s, count, omap_serial_early_putc);
1174 }
1175
1176 static int __init early_omap_serial_setup(struct earlycon_device *device,
1177                                           const char *options)
1178 {
1179         struct uart_port *port = &device->port;
1180
1181         if (!(device->port.membase || device->port.iobase))
1182                 return -ENODEV;
1183
1184         port->regshift = 2;
1185         device->con->write = early_omap_serial_write;
1186         return 0;
1187 }
1188
1189 OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1190 OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1191 OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1192 #endif /* CONFIG_SERIAL_EARLYCON */
1193
1194 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1195
1196 static struct uart_driver serial_omap_reg;
1197
1198 static void serial_omap_console_putchar(struct uart_port *port, unsigned char ch)
1199 {
1200         struct uart_omap_port *up = to_uart_omap_port(port);
1201
1202         wait_for_xmitr(up);
1203         serial_out(up, UART_TX, ch);
1204 }
1205
1206 static void
1207 serial_omap_console_write(struct console *co, const char *s,
1208                 unsigned int count)
1209 {
1210         struct uart_omap_port *up = serial_omap_console_ports[co->index];
1211         unsigned long flags;
1212         unsigned int ier;
1213         int locked = 1;
1214
1215         if (oops_in_progress)
1216                 locked = uart_port_trylock_irqsave(&up->port, &flags);
1217         else
1218                 uart_port_lock_irqsave(&up->port, &flags);
1219
1220         /*
1221          * First save the IER then disable the interrupts
1222          */
1223         ier = serial_in(up, UART_IER);
1224         serial_out(up, UART_IER, 0);
1225
1226         uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1227
1228         /*
1229          * Finally, wait for transmitter to become empty
1230          * and restore the IER
1231          */
1232         wait_for_xmitr(up);
1233         serial_out(up, UART_IER, ier);
1234         /*
1235          * The receive handling will happen properly because the
1236          * receive ready bit will still be set; it is not cleared
1237          * on read.  However, modem control will not, we must
1238          * call it if we have saved something in the saved flags
1239          * while processing with interrupts off.
1240          */
1241         if (up->msr_saved_flags)
1242                 check_modem_status(up);
1243
1244         if (locked)
1245                 uart_port_unlock_irqrestore(&up->port, flags);
1246 }
1247
1248 static int __init
1249 serial_omap_console_setup(struct console *co, char *options)
1250 {
1251         struct uart_omap_port *up;
1252         int baud = 115200;
1253         int bits = 8;
1254         int parity = 'n';
1255         int flow = 'n';
1256
1257         if (serial_omap_console_ports[co->index] == NULL)
1258                 return -ENODEV;
1259         up = serial_omap_console_ports[co->index];
1260
1261         if (options)
1262                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1263
1264         return uart_set_options(&up->port, co, baud, parity, bits, flow);
1265 }
1266
1267 static struct console serial_omap_console = {
1268         .name           = OMAP_SERIAL_NAME,
1269         .write          = serial_omap_console_write,
1270         .device         = uart_console_device,
1271         .setup          = serial_omap_console_setup,
1272         .flags          = CON_PRINTBUFFER,
1273         .index          = -1,
1274         .data           = &serial_omap_reg,
1275 };
1276
1277 static void serial_omap_add_console_port(struct uart_omap_port *up)
1278 {
1279         serial_omap_console_ports[up->port.line] = up;
1280 }
1281
1282 #define OMAP_CONSOLE    (&serial_omap_console)
1283
1284 #else
1285
1286 #define OMAP_CONSOLE    NULL
1287
1288 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1289 {}
1290
1291 #endif
1292
1293 /* Enable or disable the rs485 support */
1294 static int
1295 serial_omap_config_rs485(struct uart_port *port, struct ktermios *termios,
1296                          struct serial_rs485 *rs485)
1297 {
1298         struct uart_omap_port *up = to_uart_omap_port(port);
1299         unsigned int mode;
1300         int val;
1301
1302         /* Disable interrupts from this port */
1303         mode = up->ier;
1304         up->ier = 0;
1305         serial_out(up, UART_IER, 0);
1306
1307         /* enable / disable rts */
1308         val = (rs485->flags & SER_RS485_ENABLED) ?
1309               SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1310         val = (rs485->flags & val) ? 1 : 0;
1311         gpiod_set_value(up->rts_gpiod, val);
1312
1313         /* Enable interrupts */
1314         up->ier = mode;
1315         serial_out(up, UART_IER, up->ier);
1316
1317         /* If RS-485 is disabled, make sure the THR interrupt is fired when
1318          * TX FIFO is below the trigger level.
1319          */
1320         if (!(rs485->flags & SER_RS485_ENABLED) &&
1321             (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1322                 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1323                 serial_out(up, UART_OMAP_SCR, up->scr);
1324         }
1325
1326         return 0;
1327 }
1328
1329 static const struct uart_ops serial_omap_pops = {
1330         .tx_empty       = serial_omap_tx_empty,
1331         .set_mctrl      = serial_omap_set_mctrl,
1332         .get_mctrl      = serial_omap_get_mctrl,
1333         .stop_tx        = serial_omap_stop_tx,
1334         .start_tx       = serial_omap_start_tx,
1335         .throttle       = serial_omap_throttle,
1336         .unthrottle     = serial_omap_unthrottle,
1337         .stop_rx        = serial_omap_stop_rx,
1338         .enable_ms      = serial_omap_enable_ms,
1339         .break_ctl      = serial_omap_break_ctl,
1340         .startup        = serial_omap_startup,
1341         .shutdown       = serial_omap_shutdown,
1342         .set_termios    = serial_omap_set_termios,
1343         .pm             = serial_omap_pm,
1344         .type           = serial_omap_type,
1345         .release_port   = serial_omap_release_port,
1346         .request_port   = serial_omap_request_port,
1347         .config_port    = serial_omap_config_port,
1348         .verify_port    = serial_omap_verify_port,
1349 #ifdef CONFIG_CONSOLE_POLL
1350         .poll_put_char  = serial_omap_poll_put_char,
1351         .poll_get_char  = serial_omap_poll_get_char,
1352 #endif
1353 };
1354
1355 static struct uart_driver serial_omap_reg = {
1356         .owner          = THIS_MODULE,
1357         .driver_name    = "OMAP-SERIAL",
1358         .dev_name       = OMAP_SERIAL_NAME,
1359         .nr             = OMAP_MAX_HSUART_PORTS,
1360         .cons           = OMAP_CONSOLE,
1361 };
1362
1363 #ifdef CONFIG_PM_SLEEP
1364 static int serial_omap_prepare(struct device *dev)
1365 {
1366         struct uart_omap_port *up = dev_get_drvdata(dev);
1367
1368         up->is_suspending = true;
1369
1370         return 0;
1371 }
1372
1373 static void serial_omap_complete(struct device *dev)
1374 {
1375         struct uart_omap_port *up = dev_get_drvdata(dev);
1376
1377         up->is_suspending = false;
1378 }
1379
1380 static int serial_omap_suspend(struct device *dev)
1381 {
1382         struct uart_omap_port *up = dev_get_drvdata(dev);
1383
1384         uart_suspend_port(&serial_omap_reg, &up->port);
1385         flush_work(&up->qos_work);
1386
1387         if (device_may_wakeup(dev))
1388                 serial_omap_enable_wakeup(up, true);
1389         else
1390                 serial_omap_enable_wakeup(up, false);
1391
1392         return 0;
1393 }
1394
1395 static int serial_omap_resume(struct device *dev)
1396 {
1397         struct uart_omap_port *up = dev_get_drvdata(dev);
1398
1399         if (device_may_wakeup(dev))
1400                 serial_omap_enable_wakeup(up, false);
1401
1402         uart_resume_port(&serial_omap_reg, &up->port);
1403
1404         return 0;
1405 }
1406 #else
1407 #define serial_omap_prepare NULL
1408 #define serial_omap_complete NULL
1409 #endif /* CONFIG_PM_SLEEP */
1410
1411 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1412 {
1413         u32 mvr, scheme;
1414         u16 revision, major, minor;
1415
1416         mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1417
1418         /* Check revision register scheme */
1419         scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1420
1421         switch (scheme) {
1422         case 0: /* Legacy Scheme: OMAP2/3 */
1423                 /* MINOR_REV[0:4], MAJOR_REV[4:7] */
1424                 major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1425                                         OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1426                 minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1427                 break;
1428         case 1:
1429                 /* New Scheme: OMAP4+ */
1430                 /* MINOR_REV[0:5], MAJOR_REV[8:10] */
1431                 major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1432                                         OMAP_UART_MVR_MAJ_SHIFT;
1433                 minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1434                 break;
1435         default:
1436                 dev_warn(up->dev,
1437                         "Unknown %s revision, defaulting to highest\n",
1438                         up->name);
1439                 /* highest possible revision */
1440                 major = 0xff;
1441                 minor = 0xff;
1442         }
1443
1444         /* normalize revision for the driver */
1445         revision = UART_BUILD_REVISION(major, minor);
1446
1447         switch (revision) {
1448         case OMAP_UART_REV_46:
1449                 up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1450                                 UART_ERRATA_i291_DMA_FORCEIDLE);
1451                 break;
1452         case OMAP_UART_REV_52:
1453                 up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1454                                 UART_ERRATA_i291_DMA_FORCEIDLE);
1455                 up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1456                 break;
1457         case OMAP_UART_REV_63:
1458                 up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1459                 up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1460                 break;
1461         default:
1462                 break;
1463         }
1464 }
1465
1466 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1467 {
1468         struct omap_uart_port_info *omap_up_info;
1469
1470         omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1471         if (!omap_up_info)
1472                 return NULL; /* out of memory */
1473
1474         of_property_read_u32(dev->of_node, "clock-frequency",
1475                                          &omap_up_info->uartclk);
1476
1477         omap_up_info->flags = UPF_BOOT_AUTOCONF;
1478
1479         return omap_up_info;
1480 }
1481
1482 static const struct serial_rs485 serial_omap_rs485_supported = {
1483         .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND |
1484                  SER_RS485_RX_DURING_TX,
1485         .delay_rts_before_send = 1,
1486         .delay_rts_after_send = 1,
1487 };
1488
1489 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1490                                    struct device *dev)
1491 {
1492         struct serial_rs485 *rs485conf = &up->port.rs485;
1493         struct device_node *np = dev->of_node;
1494         enum gpiod_flags gflags;
1495         int ret;
1496
1497         rs485conf->flags = 0;
1498         up->rts_gpiod = NULL;
1499
1500         if (!np)
1501                 return 0;
1502
1503         up->port.rs485_config = serial_omap_config_rs485;
1504         up->port.rs485_supported = serial_omap_rs485_supported;
1505
1506         ret = uart_get_rs485_mode(&up->port);
1507         if (ret)
1508                 return ret;
1509
1510         if (of_property_read_bool(np, "rs485-rts-active-high")) {
1511                 rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1512                 rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1513         } else {
1514                 rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1515                 rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1516         }
1517
1518         /* check for tx enable gpio */
1519         gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
1520                 GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
1521         up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
1522         if (IS_ERR(up->rts_gpiod)) {
1523                 ret = PTR_ERR(up->rts_gpiod);
1524                 if (ret == -EPROBE_DEFER)
1525                         return ret;
1526
1527                 up->rts_gpiod = NULL;
1528                 up->port.rs485_supported = (const struct serial_rs485) { };
1529                 if (rs485conf->flags & SER_RS485_ENABLED) {
1530                         dev_err(dev, "disabling RS-485 (rts-gpio missing in device tree)\n");
1531                         memset(rs485conf, 0, sizeof(*rs485conf));
1532                 }
1533         } else {
1534                 gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
1535         }
1536
1537         return 0;
1538 }
1539
1540 static int serial_omap_probe(struct platform_device *pdev)
1541 {
1542         struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1543         struct uart_omap_port *up;
1544         struct resource *mem;
1545         void __iomem *base;
1546         int uartirq = 0;
1547         int wakeirq = 0;
1548         int ret;
1549
1550         /* The optional wakeirq may be specified in the board dts file */
1551         if (pdev->dev.of_node) {
1552                 uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1553                 if (!uartirq)
1554                         return -EPROBE_DEFER;
1555                 wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1556                 omap_up_info = of_get_uart_port_info(&pdev->dev);
1557                 pdev->dev.platform_data = omap_up_info;
1558         } else {
1559                 uartirq = platform_get_irq(pdev, 0);
1560                 if (uartirq < 0)
1561                         return -EPROBE_DEFER;
1562         }
1563
1564         up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1565         if (!up)
1566                 return -ENOMEM;
1567
1568         base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
1569         if (IS_ERR(base))
1570                 return PTR_ERR(base);
1571
1572         up->dev = &pdev->dev;
1573         up->port.dev = &pdev->dev;
1574         up->port.type = PORT_OMAP;
1575         up->port.iotype = UPIO_MEM;
1576         up->port.irq = uartirq;
1577         up->port.regshift = 2;
1578         up->port.fifosize = 64;
1579         up->port.ops = &serial_omap_pops;
1580         up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
1581
1582         if (pdev->dev.of_node)
1583                 ret = of_alias_get_id(pdev->dev.of_node, "serial");
1584         else
1585                 ret = pdev->id;
1586
1587         if (ret < 0) {
1588                 dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1589                         ret);
1590                 goto err_port_line;
1591         }
1592         up->port.line = ret;
1593
1594         if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1595                 dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1596                         OMAP_MAX_HSUART_PORTS);
1597                 ret = -ENXIO;
1598                 goto err_port_line;
1599         }
1600
1601         up->wakeirq = wakeirq;
1602         if (!up->wakeirq)
1603                 dev_info(up->port.dev, "no wakeirq for uart%d\n",
1604                          up->port.line);
1605
1606         sprintf(up->name, "OMAP UART%d", up->port.line);
1607         up->port.mapbase = mem->start;
1608         up->port.membase = base;
1609         up->port.flags = omap_up_info->flags;
1610         up->port.uartclk = omap_up_info->uartclk;
1611         if (!up->port.uartclk) {
1612                 up->port.uartclk = DEFAULT_CLK_SPEED;
1613                 dev_warn(&pdev->dev,
1614                          "No clock speed specified: using default: %d\n",
1615                          DEFAULT_CLK_SPEED);
1616         }
1617
1618         ret = serial_omap_probe_rs485(up, &pdev->dev);
1619         if (ret < 0)
1620                 goto err_rs485;
1621
1622         up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1623         up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1624         cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
1625         INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1626
1627         platform_set_drvdata(pdev, up);
1628         if (omap_up_info->autosuspend_timeout == 0)
1629                 omap_up_info->autosuspend_timeout = -1;
1630
1631         device_init_wakeup(up->dev, true);
1632
1633         pm_runtime_enable(&pdev->dev);
1634
1635         pm_runtime_get_sync(&pdev->dev);
1636
1637         omap_serial_fill_features_erratas(up);
1638
1639         ui[up->port.line] = up;
1640         serial_omap_add_console_port(up);
1641
1642         ret = uart_add_one_port(&serial_omap_reg, &up->port);
1643         if (ret != 0)
1644                 goto err_add_port;
1645
1646         return 0;
1647
1648 err_add_port:
1649         pm_runtime_put_sync(&pdev->dev);
1650         pm_runtime_disable(&pdev->dev);
1651         cpu_latency_qos_remove_request(&up->pm_qos_request);
1652         device_init_wakeup(up->dev, false);
1653 err_rs485:
1654 err_port_line:
1655         return ret;
1656 }
1657
1658 static void serial_omap_remove(struct platform_device *dev)
1659 {
1660         struct uart_omap_port *up = platform_get_drvdata(dev);
1661
1662         pm_runtime_get_sync(up->dev);
1663
1664         uart_remove_one_port(&serial_omap_reg, &up->port);
1665
1666         pm_runtime_put_sync(up->dev);
1667         pm_runtime_disable(up->dev);
1668         cpu_latency_qos_remove_request(&up->pm_qos_request);
1669         device_init_wakeup(&dev->dev, false);
1670 }
1671
1672 /*
1673  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1674  * The access to uart register after MDR1 Access
1675  * causes UART to corrupt data.
1676  *
1677  * Need a delay =
1678  * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1679  * give 10 times as much
1680  */
1681 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1682 {
1683         u8 timeout = 255;
1684
1685         serial_out(up, UART_OMAP_MDR1, mdr1);
1686         udelay(2);
1687         serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1688                         UART_FCR_CLEAR_RCVR);
1689         /*
1690          * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1691          * TX_FIFO_E bit is 1.
1692          */
1693         while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1694                                 (UART_LSR_THRE | UART_LSR_DR))) {
1695                 timeout--;
1696                 if (!timeout) {
1697                         /* Should *never* happen. we warn and carry on */
1698                         dev_crit(up->dev, "Errata i202: timedout %x\n",
1699                                                 serial_in(up, UART_LSR));
1700                         break;
1701                 }
1702                 udelay(1);
1703         }
1704 }
1705
1706 #ifdef CONFIG_PM
1707 static void serial_omap_restore_context(struct uart_omap_port *up)
1708 {
1709         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1710                 serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1711         else
1712                 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1713
1714         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1715         serial_out(up, UART_EFR, UART_EFR_ECB);
1716         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1717         serial_out(up, UART_IER, 0x0);
1718         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1719         serial_out(up, UART_DLL, up->dll);
1720         serial_out(up, UART_DLM, up->dlh);
1721         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1722         serial_out(up, UART_IER, up->ier);
1723         serial_out(up, UART_FCR, up->fcr);
1724         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1725         serial_out(up, UART_MCR, up->mcr);
1726         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1727         serial_out(up, UART_OMAP_SCR, up->scr);
1728         serial_out(up, UART_EFR, up->efr);
1729         serial_out(up, UART_LCR, up->lcr);
1730         if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1731                 serial_omap_mdr1_errataset(up, up->mdr1);
1732         else
1733                 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1734         serial_out(up, UART_OMAP_WER, up->wer);
1735 }
1736
1737 static int serial_omap_runtime_suspend(struct device *dev)
1738 {
1739         struct uart_omap_port *up = dev_get_drvdata(dev);
1740
1741         if (!up)
1742                 return -EINVAL;
1743
1744         /*
1745         * When using 'no_console_suspend', the console UART must not be
1746         * suspended. Since driver suspend is managed by runtime suspend,
1747         * preventing runtime suspend (by returning error) will keep device
1748         * active during suspend.
1749         */
1750         if (up->is_suspending && !console_suspend_enabled &&
1751             uart_console(&up->port))
1752                 return -EBUSY;
1753
1754         up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1755
1756         serial_omap_enable_wakeup(up, true);
1757
1758         up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1759         schedule_work(&up->qos_work);
1760
1761         return 0;
1762 }
1763
1764 static int serial_omap_runtime_resume(struct device *dev)
1765 {
1766         struct uart_omap_port *up = dev_get_drvdata(dev);
1767
1768         int loss_cnt = serial_omap_get_context_loss_count(up);
1769
1770         serial_omap_enable_wakeup(up, false);
1771
1772         if (loss_cnt < 0) {
1773                 dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1774                         loss_cnt);
1775                 serial_omap_restore_context(up);
1776         } else if (up->context_loss_cnt != loss_cnt) {
1777                 serial_omap_restore_context(up);
1778         }
1779         up->latency = up->calc_latency;
1780         schedule_work(&up->qos_work);
1781
1782         return 0;
1783 }
1784 #endif
1785
1786 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1787         SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1788         SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1789                                 serial_omap_runtime_resume, NULL)
1790         .prepare        = serial_omap_prepare,
1791         .complete       = serial_omap_complete,
1792 };
1793
1794 #if defined(CONFIG_OF)
1795 static const struct of_device_id omap_serial_of_match[] = {
1796         { .compatible = "ti,omap2-uart" },
1797         { .compatible = "ti,omap3-uart" },
1798         { .compatible = "ti,omap4-uart" },
1799         {},
1800 };
1801 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1802 #endif
1803
1804 static struct platform_driver serial_omap_driver = {
1805         .probe          = serial_omap_probe,
1806         .remove_new     = serial_omap_remove,
1807         .driver         = {
1808                 .name   = OMAP_SERIAL_DRIVER_NAME,
1809                 .pm     = &serial_omap_dev_pm_ops,
1810                 .of_match_table = of_match_ptr(omap_serial_of_match),
1811         },
1812 };
1813
1814 static int __init serial_omap_init(void)
1815 {
1816         int ret;
1817
1818         ret = uart_register_driver(&serial_omap_reg);
1819         if (ret != 0)
1820                 return ret;
1821         ret = platform_driver_register(&serial_omap_driver);
1822         if (ret != 0)
1823                 uart_unregister_driver(&serial_omap_reg);
1824         return ret;
1825 }
1826
1827 static void __exit serial_omap_exit(void)
1828 {
1829         platform_driver_unregister(&serial_omap_driver);
1830         uart_unregister_driver(&serial_omap_reg);
1831 }
1832
1833 module_init(serial_omap_init);
1834 module_exit(serial_omap_exit);
1835
1836 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1837 MODULE_LICENSE("GPL");
1838 MODULE_AUTHOR("Texas Instruments Inc");