linux/arch/cris/arch-v32/drivers/sync_serial.c
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   1/*
   2 * Simple synchronous serial port driver for ETRAX FS and Artpec-3.
   3 *
   4 * Copyright (c) 2005 Axis Communications AB
   5 *
   6 * Author: Mikael Starvik
   7 *
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/kernel.h>
  12#include <linux/types.h>
  13#include <linux/errno.h>
  14#include <linux/major.h>
  15#include <linux/sched.h>
  16#include <linux/mutex.h>
  17#include <linux/interrupt.h>
  18#include <linux/poll.h>
  19#include <linux/init.h>
  20#include <linux/timer.h>
  21#include <linux/spinlock.h>
  22
  23#include <asm/io.h>
  24#include <dma.h>
  25#include <pinmux.h>
  26#include <hwregs/reg_rdwr.h>
  27#include <hwregs/sser_defs.h>
  28#include <hwregs/dma_defs.h>
  29#include <hwregs/dma.h>
  30#include <hwregs/intr_vect_defs.h>
  31#include <hwregs/intr_vect.h>
  32#include <hwregs/reg_map.h>
  33#include <asm/sync_serial.h>
  34
  35
  36/* The receiver is a bit tricky beacuse of the continuous stream of data.*/
  37/*                                                                       */
  38/* Three DMA descriptors are linked together. Each DMA descriptor is     */
  39/* responsible for port->bufchunk of a common buffer.                    */
  40/*                                                                       */
  41/* +---------------------------------------------+                       */
  42/* |   +----------+   +----------+   +----------+ |                      */
  43/* +-> | Descr[0] |-->| Descr[1] |-->| Descr[2] |-+                      */
  44/*     +----------+   +----------+   +----------+                        */
  45/*         |            |              |                                 */
  46/*         v            v              v                                 */
  47/*   +-------------------------------------+                             */
  48/*   |        BUFFER                       |                             */
  49/*   +-------------------------------------+                             */
  50/*      |<- data_avail ->|                                               */
  51/*    readp          writep                                              */
  52/*                                                                       */
  53/* If the application keeps up the pace readp will be right after writep.*/
  54/* If the application can't keep the pace we have to throw away data.    */
  55/* The idea is that readp should be ready with the data pointed out by   */
  56/* Descr[i] when the DMA has filled in Descr[i+1].                       */
  57/* Otherwise we will discard                                             */
  58/* the rest of the data pointed out by Descr1 and set readp to the start */
  59/* of Descr2                                                             */
  60
  61#define SYNC_SERIAL_MAJOR 125
  62
  63/* IN_BUFFER_SIZE should be a multiple of 6 to make sure that 24 bit */
  64/* words can be handled */
  65#define IN_BUFFER_SIZE 12288
  66#define IN_DESCR_SIZE 256
  67#define NBR_IN_DESCR (IN_BUFFER_SIZE/IN_DESCR_SIZE)
  68
  69#define OUT_BUFFER_SIZE 1024*8
  70#define NBR_OUT_DESCR 8
  71
  72#define DEFAULT_FRAME_RATE 0
  73#define DEFAULT_WORD_RATE 7
  74
  75/* NOTE: Enabling some debug will likely cause overrun or underrun,
  76 * especially if manual mode is use.
  77 */
  78#define DEBUG(x)
  79#define DEBUGREAD(x)
  80#define DEBUGWRITE(x)
  81#define DEBUGPOLL(x)
  82#define DEBUGRXINT(x)
  83#define DEBUGTXINT(x)
  84#define DEBUGTRDMA(x)
  85#define DEBUGOUTBUF(x)
  86
  87typedef struct sync_port
  88{
  89        reg_scope_instances regi_sser;
  90        reg_scope_instances regi_dmain;
  91        reg_scope_instances regi_dmaout;
  92
  93        char started; /* 1 if port has been started */
  94        char port_nbr; /* Port 0 or 1 */
  95        char busy; /* 1 if port is busy */
  96
  97        char enabled;  /* 1 if port is enabled */
  98        char use_dma;  /* 1 if port uses dma */
  99        char tr_running;
 100
 101        char init_irqs;
 102        int output;
 103        int input;
 104
 105        /* Next byte to be read by application */
 106        volatile unsigned char *volatile readp;
 107        /* Next byte to be written by etrax */
 108        volatile unsigned char *volatile writep;
 109
 110        unsigned int in_buffer_size;
 111        unsigned int inbufchunk;
 112        unsigned char out_buffer[OUT_BUFFER_SIZE] __attribute__ ((aligned(32)));
 113        unsigned char in_buffer[IN_BUFFER_SIZE]__attribute__ ((aligned(32)));
 114        unsigned char flip[IN_BUFFER_SIZE] __attribute__ ((aligned(32)));
 115        struct dma_descr_data* next_rx_desc;
 116        struct dma_descr_data* prev_rx_desc;
 117
 118        /* Pointer to the first available descriptor in the ring,
 119         * unless active_tr_descr == catch_tr_descr and a dma
 120         * transfer is active */
 121        struct dma_descr_data *active_tr_descr;
 122
 123        /* Pointer to the first allocated descriptor in the ring */
 124        struct dma_descr_data *catch_tr_descr;
 125
 126        /* Pointer to the descriptor with the current end-of-list */
 127        struct dma_descr_data *prev_tr_descr;
 128        int full;
 129
 130        /* Pointer to the first byte being read by DMA
 131         * or current position in out_buffer if not using DMA. */
 132        unsigned char *out_rd_ptr;
 133
 134        /* Number of bytes currently locked for being read by DMA */
 135        int out_buf_count;
 136
 137        dma_descr_data in_descr[NBR_IN_DESCR] __attribute__ ((__aligned__(16)));
 138        dma_descr_context in_context __attribute__ ((__aligned__(32)));
 139        dma_descr_data out_descr[NBR_OUT_DESCR]
 140                __attribute__ ((__aligned__(16)));
 141        dma_descr_context out_context __attribute__ ((__aligned__(32)));
 142        wait_queue_head_t out_wait_q;
 143        wait_queue_head_t in_wait_q;
 144
 145        spinlock_t lock;
 146} sync_port;
 147
 148static DEFINE_MUTEX(sync_serial_mutex);
 149static int etrax_sync_serial_init(void);
 150static void initialize_port(int portnbr);
 151static inline int sync_data_avail(struct sync_port *port);
 152
 153static int sync_serial_open(struct inode *, struct file*);
 154static int sync_serial_release(struct inode*, struct file*);
 155static unsigned int sync_serial_poll(struct file *filp, poll_table *wait);
 156
 157static int sync_serial_ioctl(struct file *,
 158                             unsigned int cmd, unsigned long arg);
 159static ssize_t sync_serial_write(struct file * file, const char * buf,
 160                                 size_t count, loff_t *ppos);
 161static ssize_t sync_serial_read(struct file *file, char *buf,
 162                                size_t count, loff_t *ppos);
 163
 164#if (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
 165     defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
 166    (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
 167     defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA))
 168#define SYNC_SER_DMA
 169#endif
 170
 171static void send_word(sync_port* port);
 172static void start_dma_out(struct sync_port *port, const char *data, int count);
 173static void start_dma_in(sync_port* port);
 174#ifdef SYNC_SER_DMA
 175static irqreturn_t tr_interrupt(int irq, void *dev_id);
 176static irqreturn_t rx_interrupt(int irq, void *dev_id);
 177#endif
 178
 179#if (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0) && \
 180     !defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)) || \
 181    (defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1) && \
 182     !defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA))
 183#define SYNC_SER_MANUAL
 184#endif
 185#ifdef SYNC_SER_MANUAL
 186static irqreturn_t manual_interrupt(int irq, void *dev_id);
 187#endif
 188
 189#ifdef CONFIG_ETRAXFS   /* ETRAX FS */
 190#define OUT_DMA_NBR 4
 191#define IN_DMA_NBR 5
 192#define PINMUX_SSER pinmux_sser0
 193#define SYNCSER_INST regi_sser0
 194#define SYNCSER_INTR_VECT SSER0_INTR_VECT
 195#define OUT_DMA_INST regi_dma4
 196#define IN_DMA_INST regi_dma5
 197#define DMA_OUT_INTR_VECT DMA4_INTR_VECT
 198#define DMA_IN_INTR_VECT DMA5_INTR_VECT
 199#define REQ_DMA_SYNCSER dma_sser0
 200#else                   /* Artpec-3 */
 201#define OUT_DMA_NBR 6
 202#define IN_DMA_NBR 7
 203#define PINMUX_SSER pinmux_sser
 204#define SYNCSER_INST regi_sser
 205#define SYNCSER_INTR_VECT SSER_INTR_VECT
 206#define OUT_DMA_INST regi_dma6
 207#define IN_DMA_INST regi_dma7
 208#define DMA_OUT_INTR_VECT DMA6_INTR_VECT
 209#define DMA_IN_INTR_VECT DMA7_INTR_VECT
 210#define REQ_DMA_SYNCSER dma_sser
 211#endif
 212
 213/* The ports */
 214static struct sync_port ports[]=
 215{
 216        {
 217                .regi_sser             = SYNCSER_INST,
 218                .regi_dmaout           = OUT_DMA_INST,
 219                .regi_dmain            = IN_DMA_INST,
 220#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL0_DMA)
 221                .use_dma               = 1,
 222#else
 223                .use_dma               = 0,
 224#endif
 225        }
 226#ifdef CONFIG_ETRAXFS
 227        ,
 228
 229        {
 230                .regi_sser             = regi_sser1,
 231                .regi_dmaout           = regi_dma6,
 232                .regi_dmain            = regi_dma7,
 233#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL1_DMA)
 234                .use_dma               = 1,
 235#else
 236                .use_dma               = 0,
 237#endif
 238        }
 239#endif
 240};
 241
 242#define NBR_PORTS ARRAY_SIZE(ports)
 243
 244static const struct file_operations sync_serial_fops = {
 245        .owner          = THIS_MODULE,
 246        .write          = sync_serial_write,
 247        .read           = sync_serial_read,
 248        .poll           = sync_serial_poll,
 249        .unlocked_ioctl = sync_serial_ioctl,
 250        .open           = sync_serial_open,
 251        .release        = sync_serial_release,
 252        .llseek         = noop_llseek,
 253};
 254
 255static int __init etrax_sync_serial_init(void)
 256{
 257        ports[0].enabled = 0;
 258#ifdef CONFIG_ETRAXFS
 259        ports[1].enabled = 0;
 260#endif
 261        if (register_chrdev(SYNC_SERIAL_MAJOR, "sync serial",
 262                        &sync_serial_fops) < 0) {
 263                printk(KERN_WARNING
 264                        "Unable to get major for synchronous serial port\n");
 265                return -EBUSY;
 266        }
 267
 268        /* Initialize Ports */
 269#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT0)
 270        if (crisv32_pinmux_alloc_fixed(PINMUX_SSER)) {
 271                printk(KERN_WARNING
 272                        "Unable to alloc pins for synchronous serial port 0\n");
 273                return -EIO;
 274        }
 275        ports[0].enabled = 1;
 276        initialize_port(0);
 277#endif
 278
 279#if defined(CONFIG_ETRAX_SYNCHRONOUS_SERIAL_PORT1)
 280        if (crisv32_pinmux_alloc_fixed(pinmux_sser1)) {
 281                printk(KERN_WARNING
 282                        "Unable to alloc pins for synchronous serial port 0\n");
 283                return -EIO;
 284        }
 285        ports[1].enabled = 1;
 286        initialize_port(1);
 287#endif
 288
 289#ifdef CONFIG_ETRAXFS
 290        printk(KERN_INFO "ETRAX FS synchronous serial port driver\n");
 291#else
 292        printk(KERN_INFO "Artpec-3 synchronous serial port driver\n");
 293#endif
 294        return 0;
 295}
 296
 297static void __init initialize_port(int portnbr)
 298{
 299        int __attribute__((unused)) i;
 300        struct sync_port *port = &ports[portnbr];
 301        reg_sser_rw_cfg cfg = {0};
 302        reg_sser_rw_frm_cfg frm_cfg = {0};
 303        reg_sser_rw_tr_cfg tr_cfg = {0};
 304        reg_sser_rw_rec_cfg rec_cfg = {0};
 305
 306        DEBUG(printk(KERN_DEBUG "Init sync serial port %d\n", portnbr));
 307
 308        port->port_nbr = portnbr;
 309        port->init_irqs = 1;
 310
 311        port->out_rd_ptr = port->out_buffer;
 312        port->out_buf_count = 0;
 313
 314        port->output = 1;
 315        port->input = 0;
 316
 317        port->readp = port->flip;
 318        port->writep = port->flip;
 319        port->in_buffer_size = IN_BUFFER_SIZE;
 320        port->inbufchunk = IN_DESCR_SIZE;
 321        port->next_rx_desc = &port->in_descr[0];
 322        port->prev_rx_desc = &port->in_descr[NBR_IN_DESCR-1];
 323        port->prev_rx_desc->eol = 1;
 324
 325        init_waitqueue_head(&port->out_wait_q);
 326        init_waitqueue_head(&port->in_wait_q);
 327
 328        spin_lock_init(&port->lock);
 329
 330        cfg.out_clk_src = regk_sser_intern_clk;
 331        cfg.out_clk_pol = regk_sser_pos;
 332        cfg.clk_od_mode = regk_sser_no;
 333        cfg.clk_dir = regk_sser_out;
 334        cfg.gate_clk = regk_sser_no;
 335        cfg.base_freq = regk_sser_f29_493;
 336        cfg.clk_div = 256;
 337        REG_WR(sser, port->regi_sser, rw_cfg, cfg);
 338
 339        frm_cfg.wordrate = DEFAULT_WORD_RATE;
 340        frm_cfg.type = regk_sser_edge;
 341        frm_cfg.frame_pin_dir = regk_sser_out;
 342        frm_cfg.frame_pin_use = regk_sser_frm;
 343        frm_cfg.status_pin_dir = regk_sser_in;
 344        frm_cfg.status_pin_use = regk_sser_hold;
 345        frm_cfg.out_on = regk_sser_tr;
 346        frm_cfg.tr_delay = 1;
 347        REG_WR(sser, port->regi_sser, rw_frm_cfg, frm_cfg);
 348
 349        tr_cfg.urun_stop = regk_sser_no;
 350        tr_cfg.sample_size = 7;
 351        tr_cfg.sh_dir = regk_sser_msbfirst;
 352        tr_cfg.use_dma = port->use_dma ? regk_sser_yes : regk_sser_no;
 353#if 0
 354        tr_cfg.rate_ctrl = regk_sser_bulk;
 355        tr_cfg.data_pin_use = regk_sser_dout;
 356#else
 357        tr_cfg.rate_ctrl = regk_sser_iso;
 358        tr_cfg.data_pin_use = regk_sser_dout;
 359#endif
 360        tr_cfg.bulk_wspace = 1;
 361        REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
 362
 363        rec_cfg.sample_size = 7;
 364        rec_cfg.sh_dir = regk_sser_msbfirst;
 365        rec_cfg.use_dma = port->use_dma ? regk_sser_yes : regk_sser_no;
 366        rec_cfg.fifo_thr = regk_sser_inf;
 367        REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
 368
 369#ifdef SYNC_SER_DMA
 370        /* Setup the descriptor ring for dma out/transmit. */
 371        for (i = 0; i < NBR_OUT_DESCR; i++) {
 372                port->out_descr[i].wait = 0;
 373                port->out_descr[i].intr = 1;
 374                port->out_descr[i].eol = 0;
 375                port->out_descr[i].out_eop = 0;
 376                port->out_descr[i].next =
 377                        (dma_descr_data *)virt_to_phys(&port->out_descr[i+1]);
 378        }
 379
 380        /* Create a ring from the list. */
 381        port->out_descr[NBR_OUT_DESCR-1].next =
 382                (dma_descr_data *)virt_to_phys(&port->out_descr[0]);
 383
 384        /* Setup context for traversing the ring. */
 385        port->active_tr_descr = &port->out_descr[0];
 386        port->prev_tr_descr = &port->out_descr[NBR_OUT_DESCR-1];
 387        port->catch_tr_descr = &port->out_descr[0];
 388#endif
 389}
 390
 391static inline int sync_data_avail(struct sync_port *port)
 392{
 393        int avail;
 394        unsigned char *start;
 395        unsigned char *end;
 396
 397        start = (unsigned char*)port->readp; /* cast away volatile */
 398        end = (unsigned char*)port->writep;  /* cast away volatile */
 399        /* 0123456789  0123456789
 400         *  -----      -    -----
 401         *  ^rp  ^wp    ^wp ^rp
 402         */
 403
 404        if (end >= start)
 405                avail = end - start;
 406        else
 407                avail = port->in_buffer_size - (start - end);
 408        return avail;
 409}
 410
 411static inline int sync_data_avail_to_end(struct sync_port *port)
 412{
 413        int avail;
 414        unsigned char *start;
 415        unsigned char *end;
 416
 417        start = (unsigned char*)port->readp; /* cast away volatile */
 418        end = (unsigned char*)port->writep;  /* cast away volatile */
 419        /* 0123456789  0123456789
 420         *  -----           -----
 421         *  ^rp  ^wp    ^wp ^rp
 422         */
 423
 424        if (end >= start)
 425                avail = end - start;
 426        else
 427                avail = port->flip + port->in_buffer_size - start;
 428        return avail;
 429}
 430
 431static int sync_serial_open(struct inode *inode, struct file *file)
 432{
 433        int dev = iminor(inode);
 434        int ret = -EBUSY;
 435        sync_port *port;
 436        reg_dma_rw_cfg cfg = {.en = regk_dma_yes};
 437        reg_dma_rw_intr_mask intr_mask = {.data = regk_dma_yes};
 438
 439        mutex_lock(&sync_serial_mutex);
 440        DEBUG(printk(KERN_DEBUG "Open sync serial port %d\n", dev));
 441
 442        if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
 443        {
 444                DEBUG(printk(KERN_DEBUG "Invalid minor %d\n", dev));
 445                ret = -ENODEV;
 446                goto out;
 447        }
 448        port = &ports[dev];
 449        /* Allow open this device twice (assuming one reader and one writer) */
 450        if (port->busy == 2)
 451        {
 452                DEBUG(printk(KERN_DEBUG "Device is busy.. \n"));
 453                goto out;
 454        }
 455
 456
 457        if (port->init_irqs) {
 458                if (port->use_dma) {
 459                        if (port == &ports[0]) {
 460#ifdef SYNC_SER_DMA
 461                                if (request_irq(DMA_OUT_INTR_VECT,
 462                                                tr_interrupt,
 463                                                0,
 464                                                "synchronous serial 0 dma tr",
 465                                                &ports[0])) {
 466                                        printk(KERN_CRIT "Can't allocate sync serial port 0 IRQ");
 467                                        goto out;
 468                                } else if (request_irq(DMA_IN_INTR_VECT,
 469                                                rx_interrupt,
 470                                                0,
 471                                                "synchronous serial 1 dma rx",
 472                                                &ports[0])) {
 473                                        free_irq(DMA_OUT_INTR_VECT, &port[0]);
 474                                        printk(KERN_CRIT "Can't allocate sync serial port 0 IRQ");
 475                                        goto out;
 476                                } else if (crisv32_request_dma(OUT_DMA_NBR,
 477                                                "synchronous serial 0 dma tr",
 478                                                DMA_VERBOSE_ON_ERROR,
 479                                                0,
 480                                                REQ_DMA_SYNCSER)) {
 481                                        free_irq(DMA_OUT_INTR_VECT, &port[0]);
 482                                        free_irq(DMA_IN_INTR_VECT, &port[0]);
 483                                        printk(KERN_CRIT "Can't allocate sync serial port 0 TX DMA channel");
 484                                        goto out;
 485                                } else if (crisv32_request_dma(IN_DMA_NBR,
 486                                                "synchronous serial 0 dma rec",
 487                                                DMA_VERBOSE_ON_ERROR,
 488                                                0,
 489                                                REQ_DMA_SYNCSER)) {
 490                                        crisv32_free_dma(OUT_DMA_NBR);
 491                                        free_irq(DMA_OUT_INTR_VECT, &port[0]);
 492                                        free_irq(DMA_IN_INTR_VECT, &port[0]);
 493                                        printk(KERN_CRIT "Can't allocate sync serial port 1 RX DMA channel");
 494                                        goto out;
 495                                }
 496#endif
 497                        }
 498#ifdef CONFIG_ETRAXFS
 499                        else if (port == &ports[1]) {
 500#ifdef SYNC_SER_DMA
 501                                if (request_irq(DMA6_INTR_VECT,
 502                                                tr_interrupt,
 503                                                0,
 504                                                "synchronous serial 1 dma tr",
 505                                                &ports[1])) {
 506                                        printk(KERN_CRIT "Can't allocate sync serial port 1 IRQ");
 507                                        goto out;
 508                                } else if (request_irq(DMA7_INTR_VECT,
 509                                                       rx_interrupt,
 510                                                       0,
 511                                                       "synchronous serial 1 dma rx",
 512                                                       &ports[1])) {
 513                                        free_irq(DMA6_INTR_VECT, &ports[1]);
 514                                        printk(KERN_CRIT "Can't allocate sync serial port 3 IRQ");
 515                                        goto out;
 516                                } else if (crisv32_request_dma(
 517                                                SYNC_SER1_TX_DMA_NBR,
 518                                                "synchronous serial 1 dma tr",
 519                                                DMA_VERBOSE_ON_ERROR,
 520                                                0,
 521                                                dma_sser1)) {
 522                                        free_irq(DMA6_INTR_VECT, &ports[1]);
 523                                        free_irq(DMA7_INTR_VECT, &ports[1]);
 524                                        printk(KERN_CRIT "Can't allocate sync serial port 3 TX DMA channel");
 525                                        goto out;
 526                                } else if (crisv32_request_dma(
 527                                                SYNC_SER1_RX_DMA_NBR,
 528                                                "synchronous serial 3 dma rec",
 529                                                DMA_VERBOSE_ON_ERROR,
 530                                                0,
 531                                                dma_sser1)) {
 532                                        crisv32_free_dma(SYNC_SER1_TX_DMA_NBR);
 533                                        free_irq(DMA6_INTR_VECT, &ports[1]);
 534                                        free_irq(DMA7_INTR_VECT, &ports[1]);
 535                                        printk(KERN_CRIT "Can't allocate sync serial port 3 RX DMA channel");
 536                                        goto out;
 537                                }
 538#endif
 539                        }
 540#endif
 541                        /* Enable DMAs */
 542                        REG_WR(dma, port->regi_dmain, rw_cfg, cfg);
 543                        REG_WR(dma, port->regi_dmaout, rw_cfg, cfg);
 544                        /* Enable DMA IRQs */
 545                        REG_WR(dma, port->regi_dmain, rw_intr_mask, intr_mask);
 546                        REG_WR(dma, port->regi_dmaout, rw_intr_mask, intr_mask);
 547                        /* Set up wordsize = 1 for DMAs. */
 548                        DMA_WR_CMD (port->regi_dmain, regk_dma_set_w_size1);
 549                        DMA_WR_CMD (port->regi_dmaout, regk_dma_set_w_size1);
 550
 551                        start_dma_in(port);
 552                        port->init_irqs = 0;
 553                } else { /* !port->use_dma */
 554#ifdef SYNC_SER_MANUAL
 555                        if (port == &ports[0]) {
 556                                if (request_irq(SYNCSER_INTR_VECT,
 557                                                manual_interrupt,
 558                                                0,
 559                                                "synchronous serial manual irq",
 560                                                &ports[0])) {
 561                                        printk("Can't allocate sync serial manual irq");
 562                                        goto out;
 563                                }
 564                        }
 565#ifdef CONFIG_ETRAXFS
 566                        else if (port == &ports[1]) {
 567                                if (request_irq(SSER1_INTR_VECT,
 568                                                manual_interrupt,
 569                                                0,
 570                                                "synchronous serial manual irq",
 571                                                &ports[1])) {
 572                                        printk(KERN_CRIT "Can't allocate sync serial manual irq");
 573                                        goto out;
 574                                }
 575                        }
 576#endif
 577                        port->init_irqs = 0;
 578#else
 579                        panic("sync_serial: Manual mode not supported.\n");
 580#endif /* SYNC_SER_MANUAL */
 581                }
 582
 583        } /* port->init_irqs */
 584
 585        port->busy++;
 586        ret = 0;
 587out:
 588        mutex_unlock(&sync_serial_mutex);
 589        return ret;
 590}
 591
 592static int sync_serial_release(struct inode *inode, struct file *file)
 593{
 594        int dev = iminor(inode);
 595        sync_port *port;
 596
 597        if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
 598        {
 599                DEBUG(printk("Invalid minor %d\n", dev));
 600                return -ENODEV;
 601        }
 602        port = &ports[dev];
 603        if (port->busy)
 604                port->busy--;
 605        if (!port->busy)
 606          /* XXX */ ;
 607        return 0;
 608}
 609
 610static unsigned int sync_serial_poll(struct file *file, poll_table *wait)
 611{
 612        int dev = iminor(file->f_path.dentry->d_inode);
 613        unsigned int mask = 0;
 614        sync_port *port;
 615        DEBUGPOLL( static unsigned int prev_mask = 0; );
 616
 617        port = &ports[dev];
 618
 619        if (!port->started) {
 620                reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
 621                reg_sser_rw_rec_cfg rec_cfg =
 622                        REG_RD(sser, port->regi_sser, rw_rec_cfg);
 623                cfg.en = regk_sser_yes;
 624                rec_cfg.rec_en = port->input;
 625                REG_WR(sser, port->regi_sser, rw_cfg, cfg);
 626                REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
 627                port->started = 1;
 628        }
 629
 630        poll_wait(file, &port->out_wait_q, wait);
 631        poll_wait(file, &port->in_wait_q, wait);
 632
 633        /* No active transfer, descriptors are available */
 634        if (port->output && !port->tr_running)
 635                mask |= POLLOUT | POLLWRNORM;
 636
 637        /* Descriptor and buffer space available. */
 638        if (port->output &&
 639            port->active_tr_descr != port->catch_tr_descr &&
 640            port->out_buf_count < OUT_BUFFER_SIZE)
 641                mask |=  POLLOUT | POLLWRNORM;
 642
 643        /* At least an inbufchunk of data */
 644        if (port->input && sync_data_avail(port) >= port->inbufchunk)
 645                mask |= POLLIN | POLLRDNORM;
 646
 647        DEBUGPOLL(if (mask != prev_mask)
 648              printk("sync_serial_poll: mask 0x%08X %s %s\n", mask,
 649                     mask&POLLOUT?"POLLOUT":"", mask&POLLIN?"POLLIN":"");
 650              prev_mask = mask;
 651              );
 652        return mask;
 653}
 654
 655static int sync_serial_ioctl(struct file *file,
 656                  unsigned int cmd, unsigned long arg)
 657{
 658        int return_val = 0;
 659        int dma_w_size = regk_dma_set_w_size1;
 660        int dev = iminor(file->f_path.dentry->d_inode);
 661        sync_port *port;
 662        reg_sser_rw_tr_cfg tr_cfg;
 663        reg_sser_rw_rec_cfg rec_cfg;
 664        reg_sser_rw_frm_cfg frm_cfg;
 665        reg_sser_rw_cfg gen_cfg;
 666        reg_sser_rw_intr_mask intr_mask;
 667
 668        if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
 669        {
 670                DEBUG(printk("Invalid minor %d\n", dev));
 671                return -1;
 672        }
 673        port = &ports[dev];
 674        spin_lock_irq(&port->lock);
 675
 676        tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
 677        rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
 678        frm_cfg = REG_RD(sser, port->regi_sser, rw_frm_cfg);
 679        gen_cfg = REG_RD(sser, port->regi_sser, rw_cfg);
 680        intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
 681
 682        switch(cmd)
 683        {
 684        case SSP_SPEED:
 685                if (GET_SPEED(arg) == CODEC)
 686                {
 687                        unsigned int freq;
 688
 689                        gen_cfg.base_freq = regk_sser_f32;
 690
 691                        /* Clock divider will internally be
 692                         * gen_cfg.clk_div + 1.
 693                         */
 694
 695                        freq = GET_FREQ(arg);
 696                        switch (freq) {
 697                        case FREQ_32kHz:
 698                        case FREQ_64kHz:
 699                        case FREQ_128kHz:
 700                        case FREQ_256kHz:
 701                                gen_cfg.clk_div = 125 *
 702                                        (1 << (freq - FREQ_256kHz)) - 1;
 703                        break;
 704                        case FREQ_512kHz:
 705                                gen_cfg.clk_div = 62;
 706                        break;
 707                        case FREQ_1MHz:
 708                        case FREQ_2MHz:
 709                        case FREQ_4MHz:
 710                                gen_cfg.clk_div = 8 * (1 << freq) - 1;
 711                        break;
 712                        }
 713                } else {
 714                        gen_cfg.base_freq = regk_sser_f29_493;
 715                        switch (GET_SPEED(arg)) {
 716                        case SSP150:
 717                                gen_cfg.clk_div = 29493000 / (150 * 8) - 1;
 718                                break;
 719                        case SSP300:
 720                                gen_cfg.clk_div = 29493000 / (300 * 8) - 1;
 721                                break;
 722                        case SSP600:
 723                                gen_cfg.clk_div = 29493000 / (600 * 8) - 1;
 724                                break;
 725                        case SSP1200:
 726                                gen_cfg.clk_div = 29493000 / (1200 * 8) - 1;
 727                                break;
 728                        case SSP2400:
 729                                gen_cfg.clk_div = 29493000 / (2400 * 8) - 1;
 730                                break;
 731                        case SSP4800:
 732                                gen_cfg.clk_div = 29493000 / (4800 * 8) - 1;
 733                                break;
 734                        case SSP9600:
 735                                gen_cfg.clk_div = 29493000 / (9600 * 8) - 1;
 736                                break;
 737                        case SSP19200:
 738                                gen_cfg.clk_div = 29493000 / (19200 * 8) - 1;
 739                                break;
 740                        case SSP28800:
 741                                gen_cfg.clk_div = 29493000 / (28800 * 8) - 1;
 742                                break;
 743                        case SSP57600:
 744                                gen_cfg.clk_div = 29493000 / (57600 * 8) - 1;
 745                                break;
 746                        case SSP115200:
 747                                gen_cfg.clk_div = 29493000 / (115200 * 8) - 1;
 748                                break;
 749                        case SSP230400:
 750                                gen_cfg.clk_div = 29493000 / (230400 * 8) - 1;
 751                                break;
 752                        case SSP460800:
 753                                gen_cfg.clk_div = 29493000 / (460800 * 8) - 1;
 754                                break;
 755                        case SSP921600:
 756                                gen_cfg.clk_div = 29493000 / (921600 * 8) - 1;
 757                                break;
 758                        case SSP3125000:
 759                                gen_cfg.base_freq = regk_sser_f100;
 760                                gen_cfg.clk_div = 100000000 / (3125000 * 8) - 1;
 761                                break;
 762
 763                        }
 764                }
 765                frm_cfg.wordrate = GET_WORD_RATE(arg);
 766
 767                break;
 768        case SSP_MODE:
 769                switch(arg)
 770                {
 771                        case MASTER_OUTPUT:
 772                                port->output = 1;
 773                                port->input = 0;
 774                                frm_cfg.out_on = regk_sser_tr;
 775                                frm_cfg.frame_pin_dir = regk_sser_out;
 776                                gen_cfg.clk_dir = regk_sser_out;
 777                                break;
 778                        case SLAVE_OUTPUT:
 779                                port->output = 1;
 780                                port->input = 0;
 781                                frm_cfg.frame_pin_dir = regk_sser_in;
 782                                gen_cfg.clk_dir = regk_sser_in;
 783                                break;
 784                        case MASTER_INPUT:
 785                                port->output = 0;
 786                                port->input = 1;
 787                                frm_cfg.frame_pin_dir = regk_sser_out;
 788                                frm_cfg.out_on = regk_sser_intern_tb;
 789                                gen_cfg.clk_dir = regk_sser_out;
 790                                break;
 791                        case SLAVE_INPUT:
 792                                port->output = 0;
 793                                port->input = 1;
 794                                frm_cfg.frame_pin_dir = regk_sser_in;
 795                                gen_cfg.clk_dir = regk_sser_in;
 796                                break;
 797                        case MASTER_BIDIR:
 798                                port->output = 1;
 799                                port->input = 1;
 800                                frm_cfg.frame_pin_dir = regk_sser_out;
 801                                frm_cfg.out_on = regk_sser_intern_tb;
 802                                gen_cfg.clk_dir = regk_sser_out;
 803                                break;
 804                        case SLAVE_BIDIR:
 805                                port->output = 1;
 806                                port->input = 1;
 807                                frm_cfg.frame_pin_dir = regk_sser_in;
 808                                gen_cfg.clk_dir = regk_sser_in;
 809                                break;
 810                        default:
 811                                spin_unlock_irq(&port->lock);
 812                                return -EINVAL;
 813                }
 814                if (!port->use_dma || (arg == MASTER_OUTPUT || arg == SLAVE_OUTPUT))
 815                        intr_mask.rdav = regk_sser_yes;
 816                break;
 817        case SSP_FRAME_SYNC:
 818                if (arg & NORMAL_SYNC) {
 819                        frm_cfg.rec_delay = 1;
 820                        frm_cfg.tr_delay = 1;
 821                }
 822                else if (arg & EARLY_SYNC)
 823                        frm_cfg.rec_delay = frm_cfg.tr_delay = 0;
 824                else if (arg & SECOND_WORD_SYNC) {
 825                        frm_cfg.rec_delay = 7;
 826                        frm_cfg.tr_delay = 1;
 827                }
 828
 829                tr_cfg.bulk_wspace = frm_cfg.tr_delay;
 830                frm_cfg.early_wend = regk_sser_yes;
 831                if (arg & BIT_SYNC)
 832                        frm_cfg.type = regk_sser_edge;
 833                else if (arg & WORD_SYNC)
 834                        frm_cfg.type = regk_sser_level;
 835                else if (arg & EXTENDED_SYNC)
 836                        frm_cfg.early_wend = regk_sser_no;
 837
 838                if (arg & SYNC_ON)
 839                        frm_cfg.frame_pin_use = regk_sser_frm;
 840                else if (arg & SYNC_OFF)
 841                        frm_cfg.frame_pin_use = regk_sser_gio0;
 842
 843                dma_w_size = regk_dma_set_w_size2;
 844                if (arg & WORD_SIZE_8) {
 845                        rec_cfg.sample_size = tr_cfg.sample_size = 7;
 846                        dma_w_size = regk_dma_set_w_size1;
 847                } else if (arg & WORD_SIZE_12)
 848                        rec_cfg.sample_size = tr_cfg.sample_size = 11;
 849                else if (arg & WORD_SIZE_16)
 850                        rec_cfg.sample_size = tr_cfg.sample_size = 15;
 851                else if (arg & WORD_SIZE_24)
 852                        rec_cfg.sample_size = tr_cfg.sample_size = 23;
 853                else if (arg & WORD_SIZE_32)
 854                        rec_cfg.sample_size = tr_cfg.sample_size = 31;
 855
 856                if (arg & BIT_ORDER_MSB)
 857                        rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_msbfirst;
 858                else if (arg & BIT_ORDER_LSB)
 859                        rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_lsbfirst;
 860
 861                if (arg & FLOW_CONTROL_ENABLE) {
 862                        frm_cfg.status_pin_use = regk_sser_frm;
 863                        rec_cfg.fifo_thr = regk_sser_thr16;
 864                } else if (arg & FLOW_CONTROL_DISABLE) {
 865                        frm_cfg.status_pin_use = regk_sser_gio0;
 866                        rec_cfg.fifo_thr = regk_sser_inf;
 867                }
 868
 869                if (arg & CLOCK_NOT_GATED)
 870                        gen_cfg.gate_clk = regk_sser_no;
 871                else if (arg & CLOCK_GATED)
 872                        gen_cfg.gate_clk = regk_sser_yes;
 873
 874                break;
 875        case SSP_IPOLARITY:
 876                /* NOTE!! negedge is considered NORMAL */
 877                if (arg & CLOCK_NORMAL)
 878                        rec_cfg.clk_pol = regk_sser_neg;
 879                else if (arg & CLOCK_INVERT)
 880                        rec_cfg.clk_pol = regk_sser_pos;
 881
 882                if (arg & FRAME_NORMAL)
 883                        frm_cfg.level = regk_sser_pos_hi;
 884                else if (arg & FRAME_INVERT)
 885                        frm_cfg.level = regk_sser_neg_lo;
 886
 887                if (arg & STATUS_NORMAL)
 888                        gen_cfg.hold_pol = regk_sser_pos;
 889                else if (arg & STATUS_INVERT)
 890                        gen_cfg.hold_pol = regk_sser_neg;
 891                break;
 892        case SSP_OPOLARITY:
 893                if (arg & CLOCK_NORMAL)
 894                        gen_cfg.out_clk_pol = regk_sser_pos;
 895                else if (arg & CLOCK_INVERT)
 896                        gen_cfg.out_clk_pol = regk_sser_neg;
 897
 898                if (arg & FRAME_NORMAL)
 899                        frm_cfg.level = regk_sser_pos_hi;
 900                else if (arg & FRAME_INVERT)
 901                        frm_cfg.level = regk_sser_neg_lo;
 902
 903                if (arg & STATUS_NORMAL)
 904                        gen_cfg.hold_pol = regk_sser_pos;
 905                else if (arg & STATUS_INVERT)
 906                        gen_cfg.hold_pol = regk_sser_neg;
 907                break;
 908        case SSP_SPI:
 909                rec_cfg.fifo_thr = regk_sser_inf;
 910                rec_cfg.sh_dir = tr_cfg.sh_dir = regk_sser_msbfirst;
 911                rec_cfg.sample_size = tr_cfg.sample_size = 7;
 912                frm_cfg.frame_pin_use = regk_sser_frm;
 913                frm_cfg.type = regk_sser_level;
 914                frm_cfg.tr_delay = 1;
 915                frm_cfg.level = regk_sser_neg_lo;
 916                if (arg & SPI_SLAVE)
 917                {
 918                        rec_cfg.clk_pol = regk_sser_neg;
 919                        gen_cfg.clk_dir = regk_sser_in;
 920                        port->input = 1;
 921                        port->output = 0;
 922                }
 923                else
 924                {
 925                        gen_cfg.out_clk_pol = regk_sser_pos;
 926                        port->input = 0;
 927                        port->output = 1;
 928                        gen_cfg.clk_dir = regk_sser_out;
 929                }
 930                break;
 931        case SSP_INBUFCHUNK:
 932                break;
 933        default:
 934                return_val = -1;
 935        }
 936
 937
 938        if (port->started) {
 939                rec_cfg.rec_en = port->input;
 940                gen_cfg.en = (port->output | port->input);
 941        }
 942
 943        REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
 944        REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
 945        REG_WR(sser, port->regi_sser, rw_frm_cfg, frm_cfg);
 946        REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
 947        REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
 948
 949
 950        if (cmd == SSP_FRAME_SYNC && (arg & (WORD_SIZE_8 | WORD_SIZE_12 |
 951                        WORD_SIZE_16 | WORD_SIZE_24 | WORD_SIZE_32))) {
 952                int en = gen_cfg.en;
 953                gen_cfg.en = 0;
 954                REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
 955                /* ##### Should DMA be stoped before we change dma size? */
 956                DMA_WR_CMD(port->regi_dmain, dma_w_size);
 957                DMA_WR_CMD(port->regi_dmaout, dma_w_size);
 958                gen_cfg.en = en;
 959                REG_WR(sser, port->regi_sser, rw_cfg, gen_cfg);
 960        }
 961
 962        spin_unlock_irq(&port->lock);
 963        return return_val;
 964}
 965
 966static long sync_serial_ioctl(struct file *file,
 967                             unsigned int cmd, unsigned long arg)
 968{
 969       long ret;
 970
 971       mutex_lock(&sync_serial_mutex);
 972       ret = sync_serial_ioctl_unlocked(file, cmd, arg);
 973       mutex_unlock(&sync_serial_mutex);
 974
 975       return ret;
 976}
 977
 978/* NOTE: sync_serial_write does not support concurrency */
 979static ssize_t sync_serial_write(struct file *file, const char *buf,
 980                                 size_t count, loff_t *ppos)
 981{
 982        int dev = iminor(file->f_path.dentry->d_inode);
 983        DECLARE_WAITQUEUE(wait, current);
 984        struct sync_port *port;
 985        int trunc_count;
 986        unsigned long flags;
 987        int bytes_free;
 988        int out_buf_count;
 989
 990        unsigned char *rd_ptr;       /* First allocated byte in the buffer */
 991        unsigned char *wr_ptr;       /* First free byte in the buffer */
 992        unsigned char *buf_stop_ptr; /* Last byte + 1 */
 993
 994        if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled) {
 995                DEBUG(printk("Invalid minor %d\n", dev));
 996                return -ENODEV;
 997        }
 998        port = &ports[dev];
 999
1000        /* |<-         OUT_BUFFER_SIZE                          ->|
1001         *           |<- out_buf_count ->|
1002         *                               |<- trunc_count ->| ...->|
1003         *  ______________________________________________________
1004         * |  free   |   data            | free                   |
1005         * |_________|___________________|________________________|
1006         *           ^ rd_ptr            ^ wr_ptr
1007         */
1008        DEBUGWRITE(printk(KERN_DEBUG "W d%d c %lu a: %p c: %p\n",
1009                          port->port_nbr, count, port->active_tr_descr,
1010                          port->catch_tr_descr));
1011
1012        /* Read variables that may be updated by interrupts */
1013        spin_lock_irqsave(&port->lock, flags);
1014        rd_ptr = port->out_rd_ptr;
1015        out_buf_count = port->out_buf_count;
1016        spin_unlock_irqrestore(&port->lock, flags);
1017
1018        /* Check if resources are available */
1019        if (port->tr_running &&
1020            ((port->use_dma && port->active_tr_descr == port->catch_tr_descr) ||
1021             out_buf_count >= OUT_BUFFER_SIZE)) {
1022                DEBUGWRITE(printk(KERN_DEBUG "sser%d full\n", dev));
1023                return -EAGAIN;
1024        }
1025
1026        buf_stop_ptr = port->out_buffer + OUT_BUFFER_SIZE;
1027
1028        /* Determine pointer to the first free byte, before copying. */
1029        wr_ptr = rd_ptr + out_buf_count;
1030        if (wr_ptr >= buf_stop_ptr)
1031                wr_ptr -= OUT_BUFFER_SIZE;
1032
1033        /* If we wrap the ring buffer, let the user space program handle it by
1034         * truncating the data. This could be more elegant, small buffer
1035         * fragments may occur.
1036         */
1037        bytes_free = OUT_BUFFER_SIZE - out_buf_count;
1038        if (wr_ptr + bytes_free > buf_stop_ptr)
1039                bytes_free = buf_stop_ptr - wr_ptr;
1040        trunc_count = (count < bytes_free) ? count : bytes_free;
1041
1042        if (copy_from_user(wr_ptr, buf, trunc_count))
1043                return -EFAULT;
1044
1045        DEBUGOUTBUF(printk(KERN_DEBUG "%-4d + %-4d = %-4d     %p %p %p\n",
1046                           out_buf_count, trunc_count,
1047                           port->out_buf_count, port->out_buffer,
1048                           wr_ptr, buf_stop_ptr));
1049
1050        /* Make sure transmitter/receiver is running */
1051        if (!port->started) {
1052                reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
1053                reg_sser_rw_rec_cfg rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
1054                cfg.en = regk_sser_yes;
1055                rec_cfg.rec_en = port->input;
1056                REG_WR(sser, port->regi_sser, rw_cfg, cfg);
1057                REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
1058                port->started = 1;
1059        }
1060
1061        /* Setup wait if blocking */
1062        if (!(file->f_flags & O_NONBLOCK)) {
1063                add_wait_queue(&port->out_wait_q, &wait);
1064                set_current_state(TASK_INTERRUPTIBLE);
1065        }
1066
1067        spin_lock_irqsave(&port->lock, flags);
1068        port->out_buf_count += trunc_count;
1069        if (port->use_dma) {
1070                start_dma_out(port, wr_ptr, trunc_count);
1071        } else if (!port->tr_running) {
1072                reg_sser_rw_intr_mask intr_mask;
1073                intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
1074                /* Start sender by writing data */
1075                send_word(port);
1076                /* and enable transmitter ready IRQ */
1077                intr_mask.trdy = 1;
1078                REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
1079        }
1080        spin_unlock_irqrestore(&port->lock, flags);
1081
1082        /* Exit if non blocking */
1083        if (file->f_flags & O_NONBLOCK) {
1084                DEBUGWRITE(printk(KERN_DEBUG "w d%d c %lu  %08x\n",
1085                                  port->port_nbr, trunc_count,
1086                                  REG_RD_INT(dma, port->regi_dmaout, r_intr)));
1087                return trunc_count;
1088        }
1089
1090        schedule();
1091        set_current_state(TASK_RUNNING);
1092        remove_wait_queue(&port->out_wait_q, &wait);
1093
1094        if (signal_pending(current))
1095                return -EINTR;
1096
1097        DEBUGWRITE(printk(KERN_DEBUG "w d%d c %lu\n",
1098                          port->port_nbr, trunc_count));
1099        return trunc_count;
1100}
1101
1102static ssize_t sync_serial_read(struct file * file, char * buf,
1103                                size_t count, loff_t *ppos)
1104{
1105        int dev = iminor(file->f_path.dentry->d_inode);
1106        int avail;
1107        sync_port *port;
1108        unsigned char* start;
1109        unsigned char* end;
1110        unsigned long flags;
1111
1112        if (dev < 0 || dev >= NBR_PORTS || !ports[dev].enabled)
1113        {
1114                DEBUG(printk("Invalid minor %d\n", dev));
1115                return -ENODEV;
1116        }
1117        port = &ports[dev];
1118
1119        DEBUGREAD(printk("R%d c %d ri %lu wi %lu /%lu\n", dev, count, port->readp - port->flip, port->writep - port->flip, port->in_buffer_size));
1120
1121        if (!port->started)
1122        {
1123                reg_sser_rw_cfg cfg = REG_RD(sser, port->regi_sser, rw_cfg);
1124                reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
1125                reg_sser_rw_rec_cfg rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
1126                cfg.en = regk_sser_yes;
1127                tr_cfg.tr_en = regk_sser_yes;
1128                rec_cfg.rec_en = regk_sser_yes;
1129                REG_WR(sser, port->regi_sser, rw_cfg, cfg);
1130                REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1131                REG_WR(sser, port->regi_sser, rw_rec_cfg, rec_cfg);
1132                port->started = 1;
1133        }
1134
1135        /* Calculate number of available bytes */
1136        /* Save pointers to avoid that they are modified by interrupt */
1137        spin_lock_irqsave(&port->lock, flags);
1138        start = (unsigned char*)port->readp; /* cast away volatile */
1139        end = (unsigned char*)port->writep;  /* cast away volatile */
1140        spin_unlock_irqrestore(&port->lock, flags);
1141        while ((start == end) && !port->full) /* No data */
1142        {
1143                DEBUGREAD(printk(KERN_DEBUG "&"));
1144                if (file->f_flags & O_NONBLOCK)
1145                        return -EAGAIN;
1146
1147                interruptible_sleep_on(&port->in_wait_q);
1148                if (signal_pending(current))
1149                        return -EINTR;
1150
1151                spin_lock_irqsave(&port->lock, flags);
1152                start = (unsigned char*)port->readp; /* cast away volatile */
1153                end = (unsigned char*)port->writep;  /* cast away volatile */
1154                spin_unlock_irqrestore(&port->lock, flags);
1155        }
1156
1157        /* Lazy read, never return wrapped data. */
1158        if (port->full)
1159                avail = port->in_buffer_size;
1160        else if (end > start)
1161                avail = end - start;
1162        else
1163                avail = port->flip + port->in_buffer_size - start;
1164
1165        count = count > avail ? avail : count;
1166        if (copy_to_user(buf, start, count))
1167                return -EFAULT;
1168        /* Disable interrupts while updating readp */
1169        spin_lock_irqsave(&port->lock, flags);
1170        port->readp += count;
1171        if (port->readp >= port->flip + port->in_buffer_size) /* Wrap? */
1172                port->readp = port->flip;
1173        port->full = 0;
1174        spin_unlock_irqrestore(&port->lock, flags);
1175        DEBUGREAD(printk("r %d\n", count));
1176        return count;
1177}
1178
1179static void send_word(sync_port* port)
1180{
1181        reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser, rw_tr_cfg);
1182        reg_sser_rw_tr_data tr_data =  {0};
1183
1184        switch(tr_cfg.sample_size)
1185        {
1186         case 8:
1187                 port->out_buf_count--;
1188                 tr_data.data = *port->out_rd_ptr++;
1189                 REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1190                 if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1191                         port->out_rd_ptr = port->out_buffer;
1192                 break;
1193         case 12:
1194         {
1195                int data = (*port->out_rd_ptr++) << 8;
1196                data |= *port->out_rd_ptr++;
1197                port->out_buf_count -= 2;
1198                tr_data.data = data;
1199                REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1200                if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1201                        port->out_rd_ptr = port->out_buffer;
1202        }
1203        break;
1204        case 16:
1205                port->out_buf_count -= 2;
1206                tr_data.data = *(unsigned short *)port->out_rd_ptr;
1207                REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1208                port->out_rd_ptr += 2;
1209                if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1210                        port->out_rd_ptr = port->out_buffer;
1211                break;
1212        case 24:
1213                port->out_buf_count -= 3;
1214                tr_data.data = *(unsigned short *)port->out_rd_ptr;
1215                REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1216                port->out_rd_ptr += 2;
1217                tr_data.data = *port->out_rd_ptr++;
1218                REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1219                if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1220                        port->out_rd_ptr = port->out_buffer;
1221                break;
1222        case 32:
1223                port->out_buf_count -= 4;
1224                tr_data.data = *(unsigned short *)port->out_rd_ptr;
1225                REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1226                port->out_rd_ptr += 2;
1227                tr_data.data = *(unsigned short *)port->out_rd_ptr;
1228                REG_WR(sser, port->regi_sser, rw_tr_data, tr_data);
1229                port->out_rd_ptr += 2;
1230                if (port->out_rd_ptr >= port->out_buffer + OUT_BUFFER_SIZE)
1231                        port->out_rd_ptr = port->out_buffer;
1232                break;
1233        }
1234}
1235
1236static void start_dma_out(struct sync_port *port,
1237                          const char *data, int count)
1238{
1239        port->active_tr_descr->buf = (char *) virt_to_phys((char *) data);
1240        port->active_tr_descr->after = port->active_tr_descr->buf + count;
1241        port->active_tr_descr->intr = 1;
1242
1243        port->active_tr_descr->eol = 1;
1244        port->prev_tr_descr->eol = 0;
1245
1246        DEBUGTRDMA(printk(KERN_DEBUG "Inserting eolr:%p eol@:%p\n",
1247                port->prev_tr_descr, port->active_tr_descr));
1248        port->prev_tr_descr = port->active_tr_descr;
1249        port->active_tr_descr = phys_to_virt((int) port->active_tr_descr->next);
1250
1251        if (!port->tr_running) {
1252                reg_sser_rw_tr_cfg tr_cfg = REG_RD(sser, port->regi_sser,
1253                        rw_tr_cfg);
1254
1255                port->out_context.next = 0;
1256                port->out_context.saved_data =
1257                        (dma_descr_data *)virt_to_phys(port->prev_tr_descr);
1258                port->out_context.saved_data_buf = port->prev_tr_descr->buf;
1259
1260                DMA_START_CONTEXT(port->regi_dmaout,
1261                        virt_to_phys((char *)&port->out_context));
1262
1263                tr_cfg.tr_en = regk_sser_yes;
1264                REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1265                DEBUGTRDMA(printk(KERN_DEBUG "dma s\n"););
1266        } else {
1267                DMA_CONTINUE_DATA(port->regi_dmaout);
1268                DEBUGTRDMA(printk(KERN_DEBUG "dma c\n"););
1269        }
1270
1271        port->tr_running = 1;
1272}
1273
1274static void start_dma_in(sync_port *port)
1275{
1276        int i;
1277        char *buf;
1278        port->writep = port->flip;
1279
1280        if (port->writep > port->flip + port->in_buffer_size) {
1281                panic("Offset too large in sync serial driver\n");
1282                return;
1283        }
1284        buf = (char*)virt_to_phys(port->in_buffer);
1285        for (i = 0; i < NBR_IN_DESCR; i++) {
1286                port->in_descr[i].buf = buf;
1287                port->in_descr[i].after = buf + port->inbufchunk;
1288                port->in_descr[i].intr = 1;
1289                port->in_descr[i].next = (dma_descr_data*)virt_to_phys(&port->in_descr[i+1]);
1290                port->in_descr[i].buf = buf;
1291                buf += port->inbufchunk;
1292        }
1293        /* Link the last descriptor to the first */
1294        port->in_descr[i-1].next = (dma_descr_data*)virt_to_phys(&port->in_descr[0]);
1295        port->in_descr[i-1].eol = regk_sser_yes;
1296        port->next_rx_desc = &port->in_descr[0];
1297        port->prev_rx_desc = &port->in_descr[NBR_IN_DESCR - 1];
1298        port->in_context.saved_data = (dma_descr_data*)virt_to_phys(&port->in_descr[0]);
1299        port->in_context.saved_data_buf = port->in_descr[0].buf;
1300        DMA_START_CONTEXT(port->regi_dmain, virt_to_phys(&port->in_context));
1301}
1302
1303#ifdef SYNC_SER_DMA
1304static irqreturn_t tr_interrupt(int irq, void *dev_id)
1305{
1306        reg_dma_r_masked_intr masked;
1307        reg_dma_rw_ack_intr ack_intr = {.data = regk_dma_yes};
1308        reg_dma_rw_stat stat;
1309        int i;
1310        int found = 0;
1311        int stop_sser = 0;
1312
1313        for (i = 0; i < NBR_PORTS; i++) {
1314                sync_port *port = &ports[i];
1315                if (!port->enabled  || !port->use_dma)
1316                        continue;
1317
1318                /* IRQ active for the port? */
1319                masked = REG_RD(dma, port->regi_dmaout, r_masked_intr);
1320                if (!masked.data)
1321                        continue;
1322
1323                found = 1;
1324
1325                /* Check if we should stop the DMA transfer */
1326                stat = REG_RD(dma, port->regi_dmaout, rw_stat);
1327                if (stat.list_state == regk_dma_data_at_eol)
1328                        stop_sser = 1;
1329
1330                /* Clear IRQ */
1331                REG_WR(dma, port->regi_dmaout, rw_ack_intr, ack_intr);
1332
1333                if (!stop_sser) {
1334                        /* The DMA has completed a descriptor, EOL was not
1335                         * encountered, so step relevant descriptor and
1336                         * datapointers forward. */
1337                        int sent;
1338                        sent = port->catch_tr_descr->after -
1339                                port->catch_tr_descr->buf;
1340                        DEBUGTXINT(printk(KERN_DEBUG "%-4d - %-4d = %-4d\t"
1341                                          "in descr %p (ac: %p)\n",
1342                                          port->out_buf_count, sent,
1343                                          port->out_buf_count - sent,
1344                                          port->catch_tr_descr,
1345                                          port->active_tr_descr););
1346                        port->out_buf_count -= sent;
1347                        port->catch_tr_descr =
1348                                phys_to_virt((int) port->catch_tr_descr->next);
1349                        port->out_rd_ptr =
1350                                phys_to_virt((int) port->catch_tr_descr->buf);
1351                } else {
1352                        int i, sent;
1353                        /* EOL handler.
1354                         * Note that if an EOL was encountered during the irq
1355                         * locked section of sync_ser_write the DMA will be
1356                         * restarted and the eol flag will be cleared.
1357                         * The remaining descriptors will be traversed by
1358                         * the descriptor interrupts as usual.
1359                         */
1360                        i = 0;
1361                        while (!port->catch_tr_descr->eol) {
1362                                sent = port->catch_tr_descr->after -
1363                                        port->catch_tr_descr->buf;
1364                                DEBUGOUTBUF(printk(KERN_DEBUG
1365                                        "traversing descr %p -%d (%d)\n",
1366                                        port->catch_tr_descr,
1367                                        sent,
1368                                        port->out_buf_count));
1369                                port->out_buf_count -= sent;
1370                                port->catch_tr_descr = phys_to_virt(
1371                                        (int)port->catch_tr_descr->next);
1372                                i++;
1373                                if (i >= NBR_OUT_DESCR) {
1374                                        /* TODO: Reset and recover */
1375                                        panic("sync_serial: missing eol");
1376                                }
1377                        }
1378                        sent = port->catch_tr_descr->after -
1379                                port->catch_tr_descr->buf;
1380                        DEBUGOUTBUF(printk(KERN_DEBUG
1381                                "eol at descr %p -%d (%d)\n",
1382                                port->catch_tr_descr,
1383                                sent,
1384                                port->out_buf_count));
1385
1386                        port->out_buf_count -= sent;
1387
1388                        /* Update read pointer to first free byte, we
1389                         * may already be writing data there. */
1390                        port->out_rd_ptr =
1391                                phys_to_virt((int) port->catch_tr_descr->after);
1392                        if (port->out_rd_ptr > port->out_buffer +
1393                                        OUT_BUFFER_SIZE)
1394                                port->out_rd_ptr = port->out_buffer;
1395
1396                        reg_sser_rw_tr_cfg tr_cfg =
1397                                REG_RD(sser, port->regi_sser, rw_tr_cfg);
1398                        DEBUGTXINT(printk(KERN_DEBUG
1399                                "tr_int DMA stop %d, set catch @ %p\n",
1400                                port->out_buf_count,
1401                                port->active_tr_descr));
1402                        if (port->out_buf_count != 0)
1403                                printk(KERN_CRIT "sync_ser: buffer not "
1404                                        "empty after eol.\n");
1405                        port->catch_tr_descr = port->active_tr_descr;
1406                        port->tr_running = 0;
1407                        tr_cfg.tr_en = regk_sser_no;
1408                        REG_WR(sser, port->regi_sser, rw_tr_cfg, tr_cfg);
1409                }
1410                /* wake up the waiting process */
1411                wake_up_interruptible(&port->out_wait_q);
1412        }
1413        return IRQ_RETVAL(found);
1414} /* tr_interrupt */
1415
1416static irqreturn_t rx_interrupt(int irq, void *dev_id)
1417{
1418        reg_dma_r_masked_intr masked;
1419        reg_dma_rw_ack_intr ack_intr = {.data = regk_dma_yes};
1420
1421        int i;
1422        int found = 0;
1423
1424        for (i = 0; i < NBR_PORTS; i++)
1425        {
1426                sync_port *port = &ports[i];
1427
1428                if (!port->enabled || !port->use_dma )
1429                        continue;
1430
1431                masked = REG_RD(dma, port->regi_dmain, r_masked_intr);
1432
1433                if (masked.data) /* Descriptor interrupt */
1434                {
1435                        found = 1;
1436                        while (REG_RD(dma, port->regi_dmain, rw_data) !=
1437                               virt_to_phys(port->next_rx_desc)) {
1438                                DEBUGRXINT(printk(KERN_DEBUG "!"));
1439                                if (port->writep + port->inbufchunk > port->flip + port->in_buffer_size) {
1440                                        int first_size = port->flip + port->in_buffer_size - port->writep;
1441                                        memcpy((char*)port->writep, phys_to_virt((unsigned)port->next_rx_desc->buf), first_size);
1442                                        memcpy(port->flip, phys_to_virt((unsigned)port->next_rx_desc->buf+first_size), port->inbufchunk - first_size);
1443                                        port->writep = port->flip + port->inbufchunk - first_size;
1444                                } else {
1445                                        memcpy((char*)port->writep,
1446                                               phys_to_virt((unsigned)port->next_rx_desc->buf),
1447                                               port->inbufchunk);
1448                                        port->writep += port->inbufchunk;
1449                                        if (port->writep >= port->flip + port->in_buffer_size)
1450                                                port->writep = port->flip;
1451                                }
1452                                if (port->writep == port->readp)
1453                                {
1454                                  port->full = 1;
1455                                }
1456
1457                                port->next_rx_desc->eol = 1;
1458                                port->prev_rx_desc->eol = 0;
1459                                /* Cache bug workaround */
1460                                flush_dma_descr(port->prev_rx_desc, 0);
1461                                port->prev_rx_desc = port->next_rx_desc;
1462                                port->next_rx_desc = phys_to_virt((unsigned)port->next_rx_desc->next);
1463                                /* Cache bug workaround */
1464                                flush_dma_descr(port->prev_rx_desc, 1);
1465                                /* wake up the waiting process */
1466                                wake_up_interruptible(&port->in_wait_q);
1467                                DMA_CONTINUE(port->regi_dmain);
1468                                REG_WR(dma, port->regi_dmain, rw_ack_intr, ack_intr);
1469
1470                        }
1471                }
1472        }
1473        return IRQ_RETVAL(found);
1474} /* rx_interrupt */
1475#endif /* SYNC_SER_DMA */
1476
1477#ifdef SYNC_SER_MANUAL
1478static irqreturn_t manual_interrupt(int irq, void *dev_id)
1479{
1480        int i;
1481        int found = 0;
1482        reg_sser_r_masked_intr masked;
1483
1484        for (i = 0; i < NBR_PORTS; i++)
1485        {
1486                sync_port *port = &ports[i];
1487
1488                if (!port->enabled || port->use_dma)
1489                {
1490                        continue;
1491                }
1492
1493                masked = REG_RD(sser, port->regi_sser, r_masked_intr);
1494                if (masked.rdav)        /* Data received? */
1495                {
1496                        reg_sser_rw_rec_cfg rec_cfg = REG_RD(sser, port->regi_sser, rw_rec_cfg);
1497                        reg_sser_r_rec_data data = REG_RD(sser, port->regi_sser, r_rec_data);
1498                        found = 1;
1499                        /* Read data */
1500                        switch(rec_cfg.sample_size)
1501                        {
1502                        case 8:
1503                                *port->writep++ = data.data & 0xff;
1504                                break;
1505                        case 12:
1506                                *port->writep = (data.data & 0x0ff0) >> 4;
1507                                *(port->writep + 1) = data.data & 0x0f;
1508                                port->writep+=2;
1509                                break;
1510                        case 16:
1511                                *(unsigned short*)port->writep = data.data;
1512                                port->writep+=2;
1513                                break;
1514                        case 24:
1515                                *(unsigned int*)port->writep = data.data;
1516                                port->writep+=3;
1517                                break;
1518                        case 32:
1519                                *(unsigned int*)port->writep = data.data;
1520                                port->writep+=4;
1521                                break;
1522                        }
1523
1524                        if (port->writep >= port->flip + port->in_buffer_size) /* Wrap? */
1525                                port->writep = port->flip;
1526                        if (port->writep == port->readp) {
1527                                /* receive buffer overrun, discard oldest data
1528                                 */
1529                                port->readp++;
1530                                if (port->readp >= port->flip + port->in_buffer_size) /* Wrap? */
1531                                        port->readp = port->flip;
1532                        }
1533                        if (sync_data_avail(port) >= port->inbufchunk)
1534                                wake_up_interruptible(&port->in_wait_q); /* Wake up application */
1535                }
1536
1537                if (masked.trdy) /* Transmitter ready? */
1538                {
1539                        found = 1;
1540                        if (port->out_buf_count > 0) /* More data to send */
1541                                send_word(port);
1542                        else /* transmission finished */
1543                        {
1544                                reg_sser_rw_intr_mask intr_mask;
1545                                intr_mask = REG_RD(sser, port->regi_sser, rw_intr_mask);
1546                                intr_mask.trdy = 0;
1547                                REG_WR(sser, port->regi_sser, rw_intr_mask, intr_mask);
1548                                wake_up_interruptible(&port->out_wait_q); /* Wake up application */
1549                        }
1550                }
1551        }
1552        return IRQ_RETVAL(found);
1553}
1554#endif
1555
1556module_init(etrax_sync_serial_init);
1557