drivers/tty/serial/men_z135_uart.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * MEN 16z135 High Speed UART
   4  *
   5  * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
   6  * Author: Johannes Thumshirn <johannes.thumshirn@men.de>
   7  */
   8 #define pr_fmt(fmt) KBUILD_MODNAME ":" fmt
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/serial_core.h>
  14 #include <linux/ioport.h>
  15 #include <linux/io.h>
  16 #include <linux/tty_flip.h>
  17 #include <linux/bitops.h>
  18 #include <linux/mcb.h>
  19
  20 #define MEN_Z135_MAX_PORTS              12
  21 #define MEN_Z135_BASECLK                29491200
  22 #define MEN_Z135_FIFO_SIZE              1024
  23 #define MEN_Z135_FIFO_WATERMARK         1020
  24
  25 #define MEN_Z135_STAT_REG               0x0
  26 #define MEN_Z135_RX_RAM                 0x4
  27 #define MEN_Z135_TX_RAM                 0x400
  28 #define MEN_Z135_RX_CTRL                0x800
  29 #define MEN_Z135_TX_CTRL                0x804
  30 #define MEN_Z135_CONF_REG               0x808
  31 #define MEN_Z135_UART_FREQ              0x80c
  32 #define MEN_Z135_BAUD_REG               0x810
  33 #define MEN_Z135_TIMEOUT                0x814
  34
  35 #define IRQ_ID(x) ((x) & 0x1f)
  36
  37 #define MEN_Z135_IER_RXCIEN BIT(0)              /* RX Space IRQ */
  38 #define MEN_Z135_IER_TXCIEN BIT(1)              /* TX Space IRQ */
  39 #define MEN_Z135_IER_RLSIEN BIT(2)              /* Receiver Line Status IRQ */
  40 #define MEN_Z135_IER_MSIEN  BIT(3)              /* Modem Status IRQ */
  41 #define MEN_Z135_ALL_IRQS (MEN_Z135_IER_RXCIEN          \
  42                                 | MEN_Z135_IER_RLSIEN   \
  43                                 | MEN_Z135_IER_MSIEN    \
  44                                 | MEN_Z135_IER_TXCIEN)
  45
  46 #define MEN_Z135_MCR_DTR        BIT(24)
  47 #define MEN_Z135_MCR_RTS        BIT(25)
  48 #define MEN_Z135_MCR_OUT1       BIT(26)
  49 #define MEN_Z135_MCR_OUT2       BIT(27)
  50 #define MEN_Z135_MCR_LOOP       BIT(28)
  51 #define MEN_Z135_MCR_RCFC       BIT(29)
  52
  53 #define MEN_Z135_MSR_DCTS       BIT(0)
  54 #define MEN_Z135_MSR_DDSR       BIT(1)
  55 #define MEN_Z135_MSR_DRI        BIT(2)
  56 #define MEN_Z135_MSR_DDCD       BIT(3)
  57 #define MEN_Z135_MSR_CTS        BIT(4)
  58 #define MEN_Z135_MSR_DSR        BIT(5)
  59 #define MEN_Z135_MSR_RI         BIT(6)
  60 #define MEN_Z135_MSR_DCD        BIT(7)
  61
  62 #define MEN_Z135_LCR_SHIFT 8    /* LCR shift mask */
  63
  64 #define MEN_Z135_WL5 0          /* CS5 */
  65 #define MEN_Z135_WL6 1          /* CS6 */
  66 #define MEN_Z135_WL7 2          /* CS7 */
  67 #define MEN_Z135_WL8 3          /* CS8 */
  68
  69 #define MEN_Z135_STB_SHIFT 2    /* Stopbits */
  70 #define MEN_Z135_NSTB1 0
  71 #define MEN_Z135_NSTB2 1
  72
  73 #define MEN_Z135_PEN_SHIFT 3    /* Parity enable */
  74 #define MEN_Z135_PAR_DIS 0
  75 #define MEN_Z135_PAR_ENA 1
  76
  77 #define MEN_Z135_PTY_SHIFT 4    /* Parity type */
  78 #define MEN_Z135_PTY_ODD 0
  79 #define MEN_Z135_PTY_EVN 1
  80
  81 #define MEN_Z135_LSR_DR BIT(0)
  82 #define MEN_Z135_LSR_OE BIT(1)
  83 #define MEN_Z135_LSR_PE BIT(2)
  84 #define MEN_Z135_LSR_FE BIT(3)
  85 #define MEN_Z135_LSR_BI BIT(4)
  86 #define MEN_Z135_LSR_THEP BIT(5)
  87 #define MEN_Z135_LSR_TEXP BIT(6)
  88 #define MEN_Z135_LSR_RXFIFOERR BIT(7)
  89
  90 #define MEN_Z135_IRQ_ID_RLS BIT(0)
  91 #define MEN_Z135_IRQ_ID_RDA BIT(1)
  92 #define MEN_Z135_IRQ_ID_CTI BIT(2)
  93 #define MEN_Z135_IRQ_ID_TSA BIT(3)
  94 #define MEN_Z135_IRQ_ID_MST BIT(4)
  95
  96 #define LCR(x) (((x) >> MEN_Z135_LCR_SHIFT) & 0xff)
  97
  98 #define BYTES_TO_ALIGN(x) ((x) & 0x3)
  99
 100 static int line;
 101
 102 static int txlvl = 5;
 103 module_param(txlvl, int, S_IRUGO);
 104 MODULE_PARM_DESC(txlvl, "TX IRQ trigger level 0-7, default 5 (128 byte)");
 105
 106 static int rxlvl = 6;
 107 module_param(rxlvl, int, S_IRUGO);
 108 MODULE_PARM_DESC(rxlvl, "RX IRQ trigger level 0-7, default 6 (256 byte)");
 109
 110 static int align;
 111 module_param(align, int, S_IRUGO);
 112 MODULE_PARM_DESC(align, "Keep hardware FIFO write pointer aligned, default 0");
 113
 114 static uint rx_timeout;
 115 module_param(rx_timeout, uint, S_IRUGO);
 116 MODULE_PARM_DESC(rx_timeout, "RX timeout. "
 117                 "Timeout in seconds = (timeout_reg * baud_reg * 4) / freq_reg");
 118
 119 struct men_z135_port {
 120         struct uart_port port;
 121         struct mcb_device *mdev;
 122         struct resource *mem;
 123         unsigned char *rxbuf;
 124         u32 stat_reg;
 125         spinlock_t lock;
 126         bool automode;
 127 };
 128 #define to_men_z135(port) container_of((port), struct men_z135_port, port)
 129
 130 /**
 131  * men_z135_reg_set() - Set value in register
 132  * @uart: The UART port
 133  * @addr: Register address
 134  * @val: value to set
 135  */
 136 static inline void men_z135_reg_set(struct men_z135_port *uart,
 137                                 u32 addr, u32 val)
 138 {
 139         struct uart_port *port = &uart->port;
 140         unsigned long flags;
 141         u32 reg;
 142
 143         spin_lock_irqsave(&uart->lock, flags);
 144
 145         reg = ioread32(port->membase + addr);
 146         reg |= val;
 147         iowrite32(reg, port->membase + addr);
 148
 149         spin_unlock_irqrestore(&uart->lock, flags);
 150 }
 151
 152 /**
 153  * men_z135_reg_clr() - Unset value in register
 154  * @uart: The UART port
 155  * @addr: Register address
 156  * @val: value to clear
 157  */
 158 static void men_z135_reg_clr(struct men_z135_port *uart,
 159                                 u32 addr, u32 val)
 160 {
 161         struct uart_port *port = &uart->port;
 162         unsigned long flags;
 163         u32 reg;
 164
 165         spin_lock_irqsave(&uart->lock, flags);
 166
 167         reg = ioread32(port->membase + addr);
 168         reg &= ~val;
 169         iowrite32(reg, port->membase + addr);
 170
 171         spin_unlock_irqrestore(&uart->lock, flags);
 172 }
 173
 174 /**
 175  * men_z135_handle_modem_status() - Handle change of modem status
 176  * @port: The UART port
 177  *
 178  * Handle change of modem status register. This is done by reading the "delta"
 179  * versions of DCD (Data Carrier Detect) and CTS (Clear To Send).
 180  */
 181 static void men_z135_handle_modem_status(struct men_z135_port *uart)
 182 {
 183         u8 msr;
 184
 185         msr = (uart->stat_reg >> 8) & 0xff;
 186
 187         if (msr & MEN_Z135_MSR_DDCD)
 188                 uart_handle_dcd_change(&uart->port,
 189                                 msr & MEN_Z135_MSR_DCD);
 190         if (msr & MEN_Z135_MSR_DCTS)
 191                 uart_handle_cts_change(&uart->port,
 192                                 msr & MEN_Z135_MSR_CTS);
 193 }
 194
 195 static void men_z135_handle_lsr(struct men_z135_port *uart)
 196 {
 197         struct uart_port *port = &uart->port;
 198         u8 lsr;
 199
 200         lsr = (uart->stat_reg >> 16) & 0xff;
 201
 202         if (lsr & MEN_Z135_LSR_OE)
 203                 port->icount.overrun++;
 204         if (lsr & MEN_Z135_LSR_PE)
 205                 port->icount.parity++;
 206         if (lsr & MEN_Z135_LSR_FE)
 207                 port->icount.frame++;
 208         if (lsr & MEN_Z135_LSR_BI) {
 209                 port->icount.brk++;
 210                 uart_handle_break(port);
 211         }
 212 }
 213
 214 /**
 215  * get_rx_fifo_content() - Get the number of bytes in RX FIFO
 216  * @uart: The UART port
 217  *
 218  * Read RXC register from hardware and return current FIFO fill size.
 219  */
 220 static u16 get_rx_fifo_content(struct men_z135_port *uart)
 221 {
 222         struct uart_port *port = &uart->port;
 223         u32 stat_reg;
 224         u16 rxc;
 225         u8 rxc_lo;
 226         u8 rxc_hi;
 227
 228         stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
 229         rxc_lo = stat_reg >> 24;
 230         rxc_hi = (stat_reg & 0xC0) >> 6;
 231
 232         rxc = rxc_lo | (rxc_hi << 8);
 233
 234         return rxc;
 235 }
 236
 237 /**
 238  * men_z135_handle_rx() - RX tasklet routine
 239  * @arg: Pointer to struct men_z135_port
 240  *
 241  * Copy from RX FIFO and acknowledge number of bytes copied.
 242  */
 243 static void men_z135_handle_rx(struct men_z135_port *uart)
 244 {
 245         struct uart_port *port = &uart->port;
 246         struct tty_port *tport = &port->state->port;
 247         int copied;
 248         u16 size;
 249         int room;
 250
 251         size = get_rx_fifo_content(uart);
 252
 253         if (size == 0)
 254                 return;
 255
 256         /* Avoid accidently accessing TX FIFO instead of RX FIFO. Last
 257          * longword in RX FIFO cannot be read.(0x004-0x3FF)
 258          */
 259         if (size > MEN_Z135_FIFO_WATERMARK)
 260                 size = MEN_Z135_FIFO_WATERMARK;
 261
 262         room = tty_buffer_request_room(tport, size);
 263         if (room != size)
 264                 dev_warn(&uart->mdev->dev,
 265                         "Not enough room in flip buffer, truncating to %d\n",
 266                         room);
 267
 268         if (room == 0)
 269                 return;
 270
 271         memcpy_fromio(uart->rxbuf, port->membase + MEN_Z135_RX_RAM, room);
 272         /* Be sure to first copy all data and then acknowledge it */
 273         mb();
 274         iowrite32(room, port->membase +  MEN_Z135_RX_CTRL);
 275
 276         copied = tty_insert_flip_string(tport, uart->rxbuf, room);
 277         if (copied != room)
 278                 dev_warn(&uart->mdev->dev,
 279                         "Only copied %d instead of %d bytes\n",
 280                         copied, room);
 281
 282         port->icount.rx += copied;
 283
 284         tty_flip_buffer_push(tport);
 285
 286 }
 287
 288 /**
 289  * men_z135_handle_tx() - TX tasklet routine
 290  * @arg: Pointer to struct men_z135_port
 291  *
 292  */
 293 static void men_z135_handle_tx(struct men_z135_port *uart)
 294 {
 295         struct uart_port *port = &uart->port;
 296         struct circ_buf *xmit = &port->state->xmit;
 297         u32 txc;
 298         u32 wptr;
 299         int qlen;
 300         int n;
 301         int txfree;
 302         int head;
 303         int tail;
 304         int s;
 305
 306         if (uart_circ_empty(xmit))
 307                 goto out;
 308
 309         if (uart_tx_stopped(port))
 310                 goto out;
 311
 312         if (port->x_char)
 313                 goto out;
 314
 315         /* calculate bytes to copy */
 316         qlen = uart_circ_chars_pending(xmit);
 317         if (qlen <= 0)
 318                 goto out;
 319
 320         wptr = ioread32(port->membase + MEN_Z135_TX_CTRL);
 321         txc = (wptr >> 16) & 0x3ff;
 322         wptr &= 0x3ff;
 323
 324         if (txc > MEN_Z135_FIFO_WATERMARK)
 325                 txc = MEN_Z135_FIFO_WATERMARK;
 326
 327         txfree = MEN_Z135_FIFO_WATERMARK - txc;
 328         if (txfree <= 0) {
 329                 dev_err(&uart->mdev->dev,
 330                         "Not enough room in TX FIFO have %d, need %d\n",
 331                         txfree, qlen);
 332                 goto irq_en;
 333         }
 334
 335         /* if we're not aligned, it's better to copy only 1 or 2 bytes and
 336          * then the rest.
 337          */
 338         if (align && qlen >= 3 && BYTES_TO_ALIGN(wptr))
 339                 n = 4 - BYTES_TO_ALIGN(wptr);
 340         else if (qlen > txfree)
 341                 n = txfree;
 342         else
 343                 n = qlen;
 344
 345         if (n <= 0)
 346                 goto irq_en;
 347
 348         head = xmit->head & (UART_XMIT_SIZE - 1);
 349         tail = xmit->tail & (UART_XMIT_SIZE - 1);
 350
 351         s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail;
 352         n = min(n, s);
 353
 354         memcpy_toio(port->membase + MEN_Z135_TX_RAM, &xmit->buf[xmit->tail], n);
 355         xmit->tail = (xmit->tail + n) & (UART_XMIT_SIZE - 1);
 356
 357         iowrite32(n & 0x3ff, port->membase + MEN_Z135_TX_CTRL);
 358
 359         port->icount.tx += n;
 360
 361         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 362                 uart_write_wakeup(port);
 363
 364 irq_en:
 365         if (!uart_circ_empty(xmit))
 366                 men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
 367         else
 368                 men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
 369
 370 out:
 371         return;
 372
 373 }
 374
 375 /**
 376  * men_z135_intr() - Handle legacy IRQs
 377  * @irq: The IRQ number
 378  * @data: Pointer to UART port
 379  *
 380  * Check IIR register to find the cause of the interrupt and handle it.
 381  * It is possible that multiple interrupts reason bits are set and reading
 382  * the IIR is a destructive read, so we always need to check for all possible
 383  * interrupts and handle them.
 384  */
 385 static irqreturn_t men_z135_intr(int irq, void *data)
 386 {
 387         struct men_z135_port *uart = (struct men_z135_port *)data;
 388         struct uart_port *port = &uart->port;
 389         bool handled = false;
 390         int irq_id;
 391
 392         uart->stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
 393         irq_id = IRQ_ID(uart->stat_reg);
 394
 395         if (!irq_id)
 396                 goto out;
 397
 398         spin_lock(&port->lock);
 399         /* It's save to write to IIR[7:6] RXC[9:8] */
 400         iowrite8(irq_id, port->membase + MEN_Z135_STAT_REG);
 401
 402         if (irq_id & MEN_Z135_IRQ_ID_RLS) {
 403                 men_z135_handle_lsr(uart);
 404                 handled = true;
 405         }
 406
 407         if (irq_id & (MEN_Z135_IRQ_ID_RDA | MEN_Z135_IRQ_ID_CTI)) {
 408                 if (irq_id & MEN_Z135_IRQ_ID_CTI)
 409                         dev_dbg(&uart->mdev->dev, "Character Timeout Indication\n");
 410                 men_z135_handle_rx(uart);
 411                 handled = true;
 412         }
 413
 414         if (irq_id & MEN_Z135_IRQ_ID_TSA) {
 415                 men_z135_handle_tx(uart);
 416                 handled = true;
 417         }
 418
 419         if (irq_id & MEN_Z135_IRQ_ID_MST) {
 420                 men_z135_handle_modem_status(uart);
 421                 handled = true;
 422         }
 423
 424         spin_unlock(&port->lock);
 425 out:
 426         return IRQ_RETVAL(handled);
 427 }
 428
 429 /**
 430  * men_z135_request_irq() - Request IRQ for 16z135 core
 431  * @uart: z135 private uart port structure
 432  *
 433  * Request an IRQ for 16z135 to use. First try using MSI, if it fails
 434  * fall back to using legacy interrupts.
 435  */
 436 static int men_z135_request_irq(struct men_z135_port *uart)
 437 {
 438         struct device *dev = &uart->mdev->dev;
 439         struct uart_port *port = &uart->port;
 440         int err = 0;
 441
 442         err = request_irq(port->irq, men_z135_intr, IRQF_SHARED,
 443                         "men_z135_intr", uart);
 444         if (err)
 445                 dev_err(dev, "Error %d getting interrupt\n", err);
 446
 447         return err;
 448 }
 449
 450 /**
 451  * men_z135_tx_empty() - Handle tx_empty call
 452  * @port: The UART port
 453  *
 454  * This function tests whether the TX FIFO and shifter for the port
 455  * described by @port is empty.
 456  */
 457 static unsigned int men_z135_tx_empty(struct uart_port *port)
 458 {
 459         u32 wptr;
 460         u16 txc;
 461
 462         wptr = ioread32(port->membase + MEN_Z135_TX_CTRL);
 463         txc = (wptr >> 16) & 0x3ff;
 464
 465         if (txc == 0)
 466                 return TIOCSER_TEMT;
 467         else
 468                 return 0;
 469 }
 470
 471 /**
 472  * men_z135_set_mctrl() - Set modem control lines
 473  * @port: The UART port
 474  * @mctrl: The modem control lines
 475  *
 476  * This function sets the modem control lines for a port described by @port
 477  * to the state described by @mctrl
 478  */
 479 static void men_z135_set_mctrl(struct uart_port *port, unsigned int mctrl)
 480 {
 481         u32 old;
 482         u32 conf_reg;
 483
 484         conf_reg = old = ioread32(port->membase + MEN_Z135_CONF_REG);
 485         if (mctrl & TIOCM_RTS)
 486                 conf_reg |= MEN_Z135_MCR_RTS;
 487         else
 488                 conf_reg &= ~MEN_Z135_MCR_RTS;
 489
 490         if (mctrl & TIOCM_DTR)
 491                 conf_reg |= MEN_Z135_MCR_DTR;
 492         else
 493                 conf_reg &= ~MEN_Z135_MCR_DTR;
 494
 495         if (mctrl & TIOCM_OUT1)
 496                 conf_reg |= MEN_Z135_MCR_OUT1;
 497         else
 498                 conf_reg &= ~MEN_Z135_MCR_OUT1;
 499
 500         if (mctrl & TIOCM_OUT2)
 501                 conf_reg |= MEN_Z135_MCR_OUT2;
 502         else
 503                 conf_reg &= ~MEN_Z135_MCR_OUT2;
 504
 505         if (mctrl & TIOCM_LOOP)
 506                 conf_reg |= MEN_Z135_MCR_LOOP;
 507         else
 508                 conf_reg &= ~MEN_Z135_MCR_LOOP;
 509
 510         if (conf_reg != old)
 511                 iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
 512 }
 513
 514 /**
 515  * men_z135_get_mctrl() - Get modem control lines
 516  * @port: The UART port
 517  *
 518  * Retruns the current state of modem control inputs.
 519  */
 520 static unsigned int men_z135_get_mctrl(struct uart_port *port)
 521 {
 522         unsigned int mctrl = 0;
 523         u8 msr;
 524
 525         msr = ioread8(port->membase + MEN_Z135_STAT_REG + 1);
 526
 527         if (msr & MEN_Z135_MSR_CTS)
 528                 mctrl |= TIOCM_CTS;
 529         if (msr & MEN_Z135_MSR_DSR)
 530                 mctrl |= TIOCM_DSR;
 531         if (msr & MEN_Z135_MSR_RI)
 532                 mctrl |= TIOCM_RI;
 533         if (msr & MEN_Z135_MSR_DCD)
 534                 mctrl |= TIOCM_CAR;
 535
 536         return mctrl;
 537 }
 538
 539 /**
 540  * men_z135_stop_tx() - Stop transmitting characters
 541  * @port: The UART port
 542  *
 543  * Stop transmitting characters. This might be due to CTS line becomming
 544  * inactive or the tty layer indicating we want to stop transmission due to
 545  * an XOFF character.
 546  */
 547 static void men_z135_stop_tx(struct uart_port *port)
 548 {
 549         struct men_z135_port *uart = to_men_z135(port);
 550
 551         men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
 552 }
 553
 554 /*
 555  * men_z135_disable_ms() - Disable Modem Status
 556  * port: The UART port
 557  *
 558  * Enable Modem Status IRQ.
 559  */
 560 static void men_z135_disable_ms(struct uart_port *port)
 561 {
 562         struct men_z135_port *uart = to_men_z135(port);
 563
 564         men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_MSIEN);
 565 }
 566
 567 /**
 568  * men_z135_start_tx() - Start transmitting characters
 569  * @port: The UART port
 570  *
 571  * Start transmitting character. This actually doesn't transmit anything, but
 572  * fires off the TX tasklet.
 573  */
 574 static void men_z135_start_tx(struct uart_port *port)
 575 {
 576         struct men_z135_port *uart = to_men_z135(port);
 577
 578         if (uart->automode)
 579                 men_z135_disable_ms(port);
 580
 581         men_z135_handle_tx(uart);
 582 }
 583
 584 /**
 585  * men_z135_stop_rx() - Stop receiving characters
 586  * @port: The UART port
 587  *
 588  * Stop receiving characters; the port is in the process of being closed.
 589  */
 590 static void men_z135_stop_rx(struct uart_port *port)
 591 {
 592         struct men_z135_port *uart = to_men_z135(port);
 593
 594         men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_RXCIEN);
 595 }
 596
 597 /**
 598  * men_z135_enable_ms() - Enable Modem Status
 599  * port:
 600  *
 601  * Enable Modem Status IRQ.
 602  */
 603 static void men_z135_enable_ms(struct uart_port *port)
 604 {
 605         struct men_z135_port *uart = to_men_z135(port);
 606
 607         men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_MSIEN);
 608 }
 609
 610 static int men_z135_startup(struct uart_port *port)
 611 {
 612         struct men_z135_port *uart = to_men_z135(port);
 613         int err;
 614         u32 conf_reg = 0;
 615
 616         err = men_z135_request_irq(uart);
 617         if (err)
 618                 return -ENODEV;
 619
 620         conf_reg = ioread32(port->membase + MEN_Z135_CONF_REG);
 621
 622         /* Activate all but TX space available IRQ */
 623         conf_reg |= MEN_Z135_ALL_IRQS & ~MEN_Z135_IER_TXCIEN;
 624         conf_reg &= ~(0xff << 16);
 625         conf_reg |= (txlvl << 16);
 626         conf_reg |= (rxlvl << 20);
 627
 628         iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
 629
 630         if (rx_timeout)
 631                 iowrite32(rx_timeout, port->membase + MEN_Z135_TIMEOUT);
 632
 633         return 0;
 634 }
 635
 636 static void men_z135_shutdown(struct uart_port *port)
 637 {
 638         struct men_z135_port *uart = to_men_z135(port);
 639         u32 conf_reg = 0;
 640
 641         conf_reg |= MEN_Z135_ALL_IRQS;
 642
 643         men_z135_reg_clr(uart, MEN_Z135_CONF_REG, conf_reg);
 644
 645         free_irq(uart->port.irq, uart);
 646 }
 647
 648 static void men_z135_set_termios(struct uart_port *port,
 649                                 struct ktermios *termios,
 650                                 struct ktermios *old)
 651 {
 652         struct men_z135_port *uart = to_men_z135(port);
 653         unsigned int baud;
 654         u32 conf_reg;
 655         u32 bd_reg;
 656         u32 uart_freq;
 657         u8 lcr;
 658
 659         conf_reg = ioread32(port->membase + MEN_Z135_CONF_REG);
 660         lcr = LCR(conf_reg);
 661
 662         /* byte size */
 663         switch (termios->c_cflag & CSIZE) {
 664         case CS5:
 665                 lcr |= MEN_Z135_WL5;
 666                 break;
 667         case CS6:
 668                 lcr |= MEN_Z135_WL6;
 669                 break;
 670         case CS7:
 671                 lcr |= MEN_Z135_WL7;
 672                 break;
 673         case CS8:
 674                 lcr |= MEN_Z135_WL8;
 675                 break;
 676         }
 677
 678         /* stop bits */
 679         if (termios->c_cflag & CSTOPB)
 680                 lcr |= MEN_Z135_NSTB2 << MEN_Z135_STB_SHIFT;
 681
 682         /* parity */
 683         if (termios->c_cflag & PARENB) {
 684                 lcr |= MEN_Z135_PAR_ENA << MEN_Z135_PEN_SHIFT;
 685
 686                 if (termios->c_cflag & PARODD)
 687                         lcr |= MEN_Z135_PTY_ODD << MEN_Z135_PTY_SHIFT;
 688                 else
 689                         lcr |= MEN_Z135_PTY_EVN << MEN_Z135_PTY_SHIFT;
 690         } else
 691                 lcr |= MEN_Z135_PAR_DIS << MEN_Z135_PEN_SHIFT;
 692
 693         conf_reg |= MEN_Z135_IER_MSIEN;
 694         if (termios->c_cflag & CRTSCTS) {
 695                 conf_reg |= MEN_Z135_MCR_RCFC;
 696                 uart->automode = true;
 697                 termios->c_cflag &= ~CLOCAL;
 698         } else {
 699                 conf_reg &= ~MEN_Z135_MCR_RCFC;
 700                 uart->automode = false;
 701         }
 702
 703         termios->c_cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
 704
 705         conf_reg |= lcr << MEN_Z135_LCR_SHIFT;
 706         iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
 707
 708         uart_freq = ioread32(port->membase + MEN_Z135_UART_FREQ);
 709         if (uart_freq == 0)
 710                 uart_freq = MEN_Z135_BASECLK;
 711
 712         baud = uart_get_baud_rate(port, termios, old, 0, uart_freq / 16);
 713
 714         spin_lock_irq(&port->lock);
 715         if (tty_termios_baud_rate(termios))
 716                 tty_termios_encode_baud_rate(termios, baud, baud);
 717
 718         bd_reg = uart_freq / (4 * baud);
 719         iowrite32(bd_reg, port->membase + MEN_Z135_BAUD_REG);
 720
 721         uart_update_timeout(port, termios->c_cflag, baud);
 722         spin_unlock_irq(&port->lock);
 723 }
 724
 725 static const char *men_z135_type(struct uart_port *port)
 726 {
 727         return KBUILD_MODNAME;
 728 }
 729
 730 static void men_z135_release_port(struct uart_port *port)
 731 {
 732         struct men_z135_port *uart = to_men_z135(port);
 733
 734         iounmap(port->membase);
 735         port->membase = NULL;
 736
 737         mcb_release_mem(uart->mem);
 738 }
 739
 740 static int men_z135_request_port(struct uart_port *port)
 741 {
 742         struct men_z135_port *uart = to_men_z135(port);
 743         struct mcb_device *mdev = uart->mdev;
 744         struct resource *mem;
 745
 746         mem = mcb_request_mem(uart->mdev, dev_name(&mdev->dev));
 747         if (IS_ERR(mem))
 748                 return PTR_ERR(mem);
 749
 750         port->mapbase = mem->start;
 751         uart->mem = mem;
 752
 753         port->membase = ioremap(mem->start, resource_size(mem));
 754         if (port->membase == NULL) {
 755                 mcb_release_mem(mem);
 756                 return -ENOMEM;
 757         }
 758
 759         return 0;
 760 }
 761
 762 static void men_z135_config_port(struct uart_port *port, int type)
 763 {
 764         port->type = PORT_MEN_Z135;
 765         men_z135_request_port(port);
 766 }
 767
 768 static int men_z135_verify_port(struct uart_port *port,
 769                                 struct serial_struct *serinfo)
 770 {
 771         return -EINVAL;
 772 }
 773
 774 static const struct uart_ops men_z135_ops = {
 775         .tx_empty = men_z135_tx_empty,
 776         .set_mctrl = men_z135_set_mctrl,
 777         .get_mctrl = men_z135_get_mctrl,
 778         .stop_tx = men_z135_stop_tx,
 779         .start_tx = men_z135_start_tx,
 780         .stop_rx = men_z135_stop_rx,
 781         .enable_ms = men_z135_enable_ms,
 782         .startup = men_z135_startup,
 783         .shutdown = men_z135_shutdown,
 784         .set_termios = men_z135_set_termios,
 785         .type = men_z135_type,
 786         .release_port = men_z135_release_port,
 787         .request_port = men_z135_request_port,
 788         .config_port = men_z135_config_port,
 789         .verify_port = men_z135_verify_port,
 790 };
 791
 792 static struct uart_driver men_z135_driver = {
 793         .owner = THIS_MODULE,
 794         .driver_name = KBUILD_MODNAME,
 795         .dev_name = "ttyHSU",
 796         .major = 0,
 797         .minor = 0,
 798         .nr = MEN_Z135_MAX_PORTS,
 799 };
 800
 801 /**
 802  * men_z135_probe() - Probe a z135 instance
 803  * @mdev: The MCB device
 804  * @id: The MCB device ID
 805  *
 806  * men_z135_probe does the basic setup of hardware resources and registers the
 807  * new uart port to the tty layer.
 808  */
 809 static int men_z135_probe(struct mcb_device *mdev,
 810                         const struct mcb_device_id *id)
 811 {
 812         struct men_z135_port *uart;
 813         struct resource *mem;
 814         struct device *dev;
 815         int err;
 816
 817         dev = &mdev->dev;
 818
 819         uart = devm_kzalloc(dev, sizeof(struct men_z135_port), GFP_KERNEL);
 820         if (!uart)
 821                 return -ENOMEM;
 822
 823         uart->rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
 824         if (!uart->rxbuf)
 825                 return -ENOMEM;
 826
 827         mem = &mdev->mem;
 828
 829         mcb_set_drvdata(mdev, uart);
 830
 831         uart->port.uartclk = MEN_Z135_BASECLK * 16;
 832         uart->port.fifosize = MEN_Z135_FIFO_SIZE;
 833         uart->port.iotype = UPIO_MEM;
 834         uart->port.ops = &men_z135_ops;
 835         uart->port.irq = mcb_get_irq(mdev);
 836         uart->port.iotype = UPIO_MEM;
 837         uart->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
 838         uart->port.line = line++;
 839         uart->port.dev = dev;
 840         uart->port.type = PORT_MEN_Z135;
 841         uart->port.mapbase = mem->start;
 842         uart->port.membase = NULL;
 843         uart->mdev = mdev;
 844
 845         spin_lock_init(&uart->lock);
 846
 847         err = uart_add_one_port(&men_z135_driver, &uart->port);
 848         if (err)
 849                 goto err;
 850
 851         return 0;
 852
 853 err:
 854         free_page((unsigned long) uart->rxbuf);
 855         dev_err(dev, "Failed to add UART: %d\n", err);
 856
 857         return err;
 858 }
 859
 860 /**
 861  * men_z135_remove() - Remove a z135 instance from the system
 862  *
 863  * @mdev: The MCB device
 864  */
 865 static void men_z135_remove(struct mcb_device *mdev)
 866 {
 867         struct men_z135_port *uart = mcb_get_drvdata(mdev);
 868
 869         line--;
 870         uart_remove_one_port(&men_z135_driver, &uart->port);
 871         free_page((unsigned long) uart->rxbuf);
 872 }
 873
 874 static const struct mcb_device_id men_z135_ids[] = {
 875         { .device = 0x87 },
 876         { }
 877 };
 878 MODULE_DEVICE_TABLE(mcb, men_z135_ids);
 879
 880 static struct mcb_driver mcb_driver = {
 881         .driver = {
 882                 .name = "z135-uart",
 883                 .owner = THIS_MODULE,
 884         },
 885         .probe = men_z135_probe,
 886         .remove = men_z135_remove,
 887         .id_table = men_z135_ids,
 888 };
 889
 890 /**
 891  * men_z135_init() - Driver Registration Routine
 892  *
 893  * men_z135_init is the first routine called when the driver is loaded. All it
 894  * does is register with the legacy MEN Chameleon subsystem.
 895  */
 896 static int __init men_z135_init(void)
 897 {
 898         int err;
 899
 900         err = uart_register_driver(&men_z135_driver);
 901         if (err) {
 902                 pr_err("Failed to register UART: %d\n", err);
 903                 return err;
 904         }
 905
 906         err = mcb_register_driver(&mcb_driver);
 907         if  (err) {
 908                 pr_err("Failed to register MCB driver: %d\n", err);
 909                 uart_unregister_driver(&men_z135_driver);
 910                 return err;
 911         }
 912
 913         return 0;
 914 }
 915 module_init(men_z135_init);
 916
 917 /**
 918  * men_z135_exit() - Driver Exit Routine
 919  *
 920  * men_z135_exit is called just before the driver is removed from memory.
 921  */
 922 static void __exit men_z135_exit(void)
 923 {
 924         mcb_unregister_driver(&mcb_driver);
 925         uart_unregister_driver(&men_z135_driver);
 926 }
 927 module_exit(men_z135_exit);
 928
 929 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
 930 MODULE_LICENSE("GPL v2");
 931 MODULE_DESCRIPTION("MEN 16z135 High Speed UART");
 932 MODULE_ALIAS("mcb:16z135");