drivers/spi/spi_mpc83xx.c

   1 /*
   2  * MPC83xx SPI controller driver.
   3  *
   4  * Maintainer: Kumar Gala
   5  *
   6  * Copyright (C) 2006 Polycom, Inc.
   7  *
   8  * This program is free software; you can redistribute  it and/or modify it
   9  * under  the terms of  the GNU General  Public License as published by the
  10  * Free Software Foundation;  either version 2 of the  License, or (at your
  11  * option) any later version.
  12  */
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/types.h>
  16 #include <linux/kernel.h>
  17 #include <linux/errno.h>
  18 #include <linux/err.h>
  19 #include <linux/completion.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/delay.h>
  22 #include <linux/irq.h>
  23 #include <linux/device.h>
  24 #include <linux/spi/spi.h>
  25 #include <linux/spi/spi_bitbang.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/fsl_devices.h>
  28 #include <linux/of.h>
  29 #include <linux/of_platform.h>
  30 #include <linux/gpio.h>
  31 #include <linux/of_gpio.h>
  32 #include <linux/of_spi.h>
  33
  34 #include <sysdev/fsl_soc.h>
  35 #include <asm/irq.h>
  36 #include <asm/io.h>
  37
  38 /* SPI Controller registers */
  39 struct mpc83xx_spi_reg {
  40         u8 res1[0x20];
  41         __be32 mode;
  42         __be32 event;
  43         __be32 mask;
  44         __be32 command;
  45         __be32 transmit;
  46         __be32 receive;
  47 };
  48
  49 /* SPI Controller mode register definitions */
  50 #define SPMODE_LOOP             (1 << 30)
  51 #define SPMODE_CI_INACTIVEHIGH  (1 << 29)
  52 #define SPMODE_CP_BEGIN_EDGECLK (1 << 28)
  53 #define SPMODE_DIV16            (1 << 27)
  54 #define SPMODE_REV              (1 << 26)
  55 #define SPMODE_MS               (1 << 25)
  56 #define SPMODE_ENABLE           (1 << 24)
  57 #define SPMODE_LEN(x)           ((x) << 20)
  58 #define SPMODE_PM(x)            ((x) << 16)
  59 #define SPMODE_OP               (1 << 14)
  60 #define SPMODE_CG(x)            ((x) << 7)
  61
  62 /*
  63  * Default for SPI Mode:
  64  *      SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk
  65  */
  66 #define SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \
  67                          SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf))
  68
  69 /* SPIE register values */
  70 #define SPIE_NE         0x00000200      /* Not empty */
  71 #define SPIE_NF         0x00000100      /* Not full */
  72
  73 /* SPIM register values */
  74 #define SPIM_NE         0x00000200      /* Not empty */
  75 #define SPIM_NF         0x00000100      /* Not full */
  76
  77 /* SPI Controller driver's private data. */
  78 struct mpc83xx_spi {
  79         struct mpc83xx_spi_reg __iomem *base;
  80
  81         /* rx & tx bufs from the spi_transfer */
  82         const void *tx;
  83         void *rx;
  84
  85         /* functions to deal with different sized buffers */
  86         void (*get_rx) (u32 rx_data, struct mpc83xx_spi *);
  87         u32(*get_tx) (struct mpc83xx_spi *);
  88
  89         unsigned int count;
  90         unsigned int irq;
  91
  92         unsigned nsecs;         /* (clock cycle time)/2 */
  93
  94         u32 spibrg;             /* SPIBRG input clock */
  95         u32 rx_shift;           /* RX data reg shift when in qe mode */
  96         u32 tx_shift;           /* TX data reg shift when in qe mode */
  97
  98         bool qe_mode;
  99
 100         u8 busy;
 101
 102         struct workqueue_struct *workqueue;
 103         struct work_struct work;
 104
 105         struct list_head queue;
 106         spinlock_t lock;
 107
 108         struct completion done;
 109 };
 110
 111 struct spi_mpc83xx_cs {
 112         /* functions to deal with different sized buffers */
 113         void (*get_rx) (u32 rx_data, struct mpc83xx_spi *);
 114         u32 (*get_tx) (struct mpc83xx_spi *);
 115         u32 rx_shift;           /* RX data reg shift when in qe mode */
 116         u32 tx_shift;           /* TX data reg shift when in qe mode */
 117         u32 hw_mode;            /* Holds HW mode register settings */
 118 };
 119
 120 static inline void mpc83xx_spi_write_reg(__be32 __iomem * reg, u32 val)
 121 {
 122         out_be32(reg, val);
 123 }
 124
 125 static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg)
 126 {
 127         return in_be32(reg);
 128 }
 129
 130 #define MPC83XX_SPI_RX_BUF(type)                                          \
 131 static                                                                    \
 132 void mpc83xx_spi_rx_buf_##type(u32 data, struct mpc83xx_spi *mpc83xx_spi) \
 133 {                                                                         \
 134         type * rx = mpc83xx_spi->rx;                                      \
 135         *rx++ = (type)(data >> mpc83xx_spi->rx_shift);                    \
 136         mpc83xx_spi->rx = rx;                                             \
 137 }
 138
 139 #define MPC83XX_SPI_TX_BUF(type)                                \
 140 static                                                          \
 141 u32 mpc83xx_spi_tx_buf_##type(struct mpc83xx_spi *mpc83xx_spi)  \
 142 {                                                               \
 143         u32 data;                                               \
 144         const type * tx = mpc83xx_spi->tx;                      \
 145         if (!tx)                                                \
 146                 return 0;                                       \
 147         data = *tx++ << mpc83xx_spi->tx_shift;                  \
 148         mpc83xx_spi->tx = tx;                                   \
 149         return data;                                            \
 150 }
 151
 152 MPC83XX_SPI_RX_BUF(u8)
 153 MPC83XX_SPI_RX_BUF(u16)
 154 MPC83XX_SPI_RX_BUF(u32)
 155 MPC83XX_SPI_TX_BUF(u8)
 156 MPC83XX_SPI_TX_BUF(u16)
 157 MPC83XX_SPI_TX_BUF(u32)
 158
 159 static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
 160 {
 161         struct mpc83xx_spi *mpc83xx_spi = spi_master_get_devdata(spi->master);
 162         struct fsl_spi_platform_data *pdata = spi->dev.parent->platform_data;
 163         bool pol = spi->mode & SPI_CS_HIGH;
 164         struct spi_mpc83xx_cs   *cs = spi->controller_state;
 165
 166         if (value == BITBANG_CS_INACTIVE) {
 167                 if (pdata->cs_control)
 168                         pdata->cs_control(spi, !pol);
 169         }
 170
 171         if (value == BITBANG_CS_ACTIVE) {
 172                 u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
 173
 174                 mpc83xx_spi->rx_shift = cs->rx_shift;
 175                 mpc83xx_spi->tx_shift = cs->tx_shift;
 176                 mpc83xx_spi->get_rx = cs->get_rx;
 177                 mpc83xx_spi->get_tx = cs->get_tx;
 178
 179                 if (cs->hw_mode != regval) {
 180                         unsigned long flags;
 181                         __be32 __iomem *mode = &mpc83xx_spi->base->mode;
 182
 183                         regval = cs->hw_mode;
 184                         /* Turn off IRQs locally to minimize time that
 185                          * SPI is disabled
 186                          */
 187                         local_irq_save(flags);
 188                         /* Turn off SPI unit prior changing mode */
 189                         mpc83xx_spi_write_reg(mode, regval & ~SPMODE_ENABLE);
 190                         mpc83xx_spi_write_reg(mode, regval);
 191                         local_irq_restore(flags);
 192                 }
 193                 if (pdata->cs_control)
 194                         pdata->cs_control(spi, pol);
 195         }
 196 }
 197
 198 static
 199 int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 200 {
 201         struct mpc83xx_spi *mpc83xx_spi;
 202         u32 regval;
 203         u8 bits_per_word, pm;
 204         u32 hz;
 205         struct spi_mpc83xx_cs   *cs = spi->controller_state;
 206
 207         mpc83xx_spi = spi_master_get_devdata(spi->master);
 208
 209         if (t) {
 210                 bits_per_word = t->bits_per_word;
 211                 hz = t->speed_hz;
 212         } else {
 213                 bits_per_word = 0;
 214                 hz = 0;
 215         }
 216
 217         /* spi_transfer level calls that work per-word */
 218         if (!bits_per_word)
 219                 bits_per_word = spi->bits_per_word;
 220
 221         /* Make sure its a bit width we support [4..16, 32] */
 222         if ((bits_per_word < 4)
 223             || ((bits_per_word > 16) && (bits_per_word != 32)))
 224                 return -EINVAL;
 225
 226         if (!hz)
 227                 hz = spi->max_speed_hz;
 228
 229         cs->rx_shift = 0;
 230         cs->tx_shift = 0;
 231         if (bits_per_word <= 8) {
 232                 cs->get_rx = mpc83xx_spi_rx_buf_u8;
 233                 cs->get_tx = mpc83xx_spi_tx_buf_u8;
 234                 if (mpc83xx_spi->qe_mode) {
 235                         cs->rx_shift = 16;
 236                         cs->tx_shift = 24;
 237                 }
 238         } else if (bits_per_word <= 16) {
 239                 cs->get_rx = mpc83xx_spi_rx_buf_u16;
 240                 cs->get_tx = mpc83xx_spi_tx_buf_u16;
 241                 if (mpc83xx_spi->qe_mode) {
 242                         cs->rx_shift = 16;
 243                         cs->tx_shift = 16;
 244                 }
 245         } else if (bits_per_word <= 32) {
 246                 cs->get_rx = mpc83xx_spi_rx_buf_u32;
 247                 cs->get_tx = mpc83xx_spi_tx_buf_u32;
 248         } else
 249                 return -EINVAL;
 250
 251         if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) {
 252                 cs->tx_shift = 0;
 253                 if (bits_per_word <= 8)
 254                         cs->rx_shift = 8;
 255                 else
 256                         cs->rx_shift = 0;
 257         }
 258
 259         mpc83xx_spi->rx_shift = cs->rx_shift;
 260         mpc83xx_spi->tx_shift = cs->tx_shift;
 261         mpc83xx_spi->get_rx = cs->get_rx;
 262         mpc83xx_spi->get_tx = cs->get_tx;
 263
 264         if (bits_per_word == 32)
 265                 bits_per_word = 0;
 266         else
 267                 bits_per_word = bits_per_word - 1;
 268
 269         /* mask out bits we are going to set */
 270         cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
 271                                   | SPMODE_PM(0xF));
 272
 273         cs->hw_mode |= SPMODE_LEN(bits_per_word);
 274
 275         if ((mpc83xx_spi->spibrg / hz) > 64) {
 276                 cs->hw_mode |= SPMODE_DIV16;
 277                 pm = mpc83xx_spi->spibrg / (hz * 64);
 278                 if (pm > 16) {
 279                         dev_err(&spi->dev, "Requested speed is too "
 280                                 "low: %d Hz. Will use %d Hz instead.\n",
 281                                 hz, mpc83xx_spi->spibrg / 1024);
 282                         pm = 16;
 283                 }
 284         } else
 285                 pm = mpc83xx_spi->spibrg / (hz * 4);
 286         if (pm)
 287                 pm--;
 288
 289         cs->hw_mode |= SPMODE_PM(pm);
 290         regval =  mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
 291         if (cs->hw_mode != regval) {
 292                 unsigned long flags;
 293                 __be32 __iomem *mode = &mpc83xx_spi->base->mode;
 294
 295                 regval = cs->hw_mode;
 296                 /* Turn off IRQs locally to minimize time
 297                  * that SPI is disabled
 298                  */
 299                 local_irq_save(flags);
 300                 /* Turn off SPI unit prior changing mode */
 301                 mpc83xx_spi_write_reg(mode, regval & ~SPMODE_ENABLE);
 302                 mpc83xx_spi_write_reg(mode, regval);
 303                 local_irq_restore(flags);
 304         }
 305         return 0;
 306 }
 307
 308 static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
 309 {
 310         struct mpc83xx_spi *mpc83xx_spi;
 311         u32 word, len, bits_per_word;
 312
 313         mpc83xx_spi = spi_master_get_devdata(spi->master);
 314
 315         mpc83xx_spi->tx = t->tx_buf;
 316         mpc83xx_spi->rx = t->rx_buf;
 317         bits_per_word = spi->bits_per_word;
 318         if (t->bits_per_word)
 319                 bits_per_word = t->bits_per_word;
 320         len = t->len;
 321         if (bits_per_word > 8) {
 322                 /* invalid length? */
 323                 if (len & 1)
 324                         return -EINVAL;
 325                 len /= 2;
 326         }
 327         if (bits_per_word > 16) {
 328                 /* invalid length? */
 329                 if (len & 1)
 330                         return -EINVAL;
 331                 len /= 2;
 332         }
 333         mpc83xx_spi->count = len;
 334
 335         INIT_COMPLETION(mpc83xx_spi->done);
 336
 337         /* enable rx ints */
 338         mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE);
 339
 340         /* transmit word */
 341         word = mpc83xx_spi->get_tx(mpc83xx_spi);
 342         mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word);
 343
 344         wait_for_completion(&mpc83xx_spi->done);
 345
 346         /* disable rx ints */
 347         mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
 348
 349         return mpc83xx_spi->count;
 350 }
 351
 352 static void mpc83xx_spi_work(struct work_struct *work)
 353 {
 354         struct mpc83xx_spi *mpc83xx_spi =
 355                 container_of(work, struct mpc83xx_spi, work);
 356
 357         spin_lock_irq(&mpc83xx_spi->lock);
 358         mpc83xx_spi->busy = 1;
 359         while (!list_empty(&mpc83xx_spi->queue)) {
 360                 struct spi_message *m;
 361                 struct spi_device *spi;
 362                 struct spi_transfer *t = NULL;
 363                 unsigned cs_change;
 364                 int status, nsecs = 50;
 365
 366                 m = container_of(mpc83xx_spi->queue.next,
 367                                 struct spi_message, queue);
 368                 list_del_init(&m->queue);
 369                 spin_unlock_irq(&mpc83xx_spi->lock);
 370
 371                 spi = m->spi;
 372                 cs_change = 1;
 373                 status = 0;
 374                 list_for_each_entry(t, &m->transfers, transfer_list) {
 375                         if (t->bits_per_word || t->speed_hz) {
 376                                 /* Don't allow changes if CS is active */
 377                                 status = -EINVAL;
 378
 379                                 if (cs_change)
 380                                         status = mpc83xx_spi_setup_transfer(spi, t);
 381                                 if (status < 0)
 382                                         break;
 383                         }
 384
 385                         if (cs_change)
 386                                 mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
 387                         cs_change = t->cs_change;
 388                         if (t->len)
 389                                 status = mpc83xx_spi_bufs(spi, t);
 390                         if (status) {
 391                                 status = -EMSGSIZE;
 392                                 break;
 393                         }
 394                         m->actual_length += t->len;
 395
 396                         if (t->delay_usecs)
 397                                 udelay(t->delay_usecs);
 398
 399                         if (cs_change) {
 400                                 ndelay(nsecs);
 401                                 mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
 402                                 ndelay(nsecs);
 403                         }
 404                 }
 405
 406                 m->status = status;
 407                 m->complete(m->context);
 408
 409                 if (status || !cs_change) {
 410                         ndelay(nsecs);
 411                         mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
 412                 }
 413
 414                 mpc83xx_spi_setup_transfer(spi, NULL);
 415
 416                 spin_lock_irq(&mpc83xx_spi->lock);
 417         }
 418         mpc83xx_spi->busy = 0;
 419         spin_unlock_irq(&mpc83xx_spi->lock);
 420 }
 421
 422 /* the spi->mode bits understood by this driver: */
 423 #define MODEBITS        (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
 424                         | SPI_LSB_FIRST | SPI_LOOP)
 425
 426 static int mpc83xx_spi_setup(struct spi_device *spi)
 427 {
 428         struct mpc83xx_spi *mpc83xx_spi;
 429         int retval;
 430         u32 hw_mode;
 431         struct spi_mpc83xx_cs   *cs = spi->controller_state;
 432
 433         if (spi->mode & ~MODEBITS) {
 434                 dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
 435                         spi->mode & ~MODEBITS);
 436                 return -EINVAL;
 437         }
 438
 439         if (!spi->max_speed_hz)
 440                 return -EINVAL;
 441
 442         if (!cs) {
 443                 cs = kzalloc(sizeof *cs, GFP_KERNEL);
 444                 if (!cs)
 445                         return -ENOMEM;
 446                 spi->controller_state = cs;
 447         }
 448         mpc83xx_spi = spi_master_get_devdata(spi->master);
 449
 450         hw_mode = cs->hw_mode; /* Save orginal settings */
 451         cs->hw_mode = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
 452         /* mask out bits we are going to set */
 453         cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
 454                          | SPMODE_REV | SPMODE_LOOP);
 455
 456         if (spi->mode & SPI_CPHA)
 457                 cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
 458         if (spi->mode & SPI_CPOL)
 459                 cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
 460         if (!(spi->mode & SPI_LSB_FIRST))
 461                 cs->hw_mode |= SPMODE_REV;
 462         if (spi->mode & SPI_LOOP)
 463                 cs->hw_mode |= SPMODE_LOOP;
 464
 465         retval = mpc83xx_spi_setup_transfer(spi, NULL);
 466         if (retval < 0) {
 467                 cs->hw_mode = hw_mode; /* Restore settings */
 468                 return retval;
 469         }
 470
 471 #if 0 /* Don't think this is needed */
 472         /* NOTE we _need_ to call chipselect() early, ideally with adapter
 473          * setup, unless the hardware defaults cooperate to avoid confusion
 474          * between normal (active low) and inverted chipselects.
 475          */
 476
 477         /* deselect chip (low or high) */
 478         spin_lock(&mpc83xx_spi->lock);
 479         if (!mpc83xx_spi->busy)
 480                 mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
 481         spin_unlock(&mpc83xx_spi->lock);
 482 #endif
 483         return 0;
 484 }
 485
 486 static irqreturn_t mpc83xx_spi_irq(s32 irq, void *context_data)
 487 {
 488         struct mpc83xx_spi *mpc83xx_spi = context_data;
 489         u32 event;
 490         irqreturn_t ret = IRQ_NONE;
 491
 492         /* Get interrupt events(tx/rx) */
 493         event = mpc83xx_spi_read_reg(&mpc83xx_spi->base->event);
 494
 495         /* We need handle RX first */
 496         if (event & SPIE_NE) {
 497                 u32 rx_data = mpc83xx_spi_read_reg(&mpc83xx_spi->base->receive);
 498
 499                 if (mpc83xx_spi->rx)
 500                         mpc83xx_spi->get_rx(rx_data, mpc83xx_spi);
 501
 502                 ret = IRQ_HANDLED;
 503         }
 504
 505         if ((event & SPIE_NF) == 0)
 506                 /* spin until TX is done */
 507                 while (((event =
 508                          mpc83xx_spi_read_reg(&mpc83xx_spi->base->event)) &
 509                                                 SPIE_NF) == 0)
 510                          cpu_relax();
 511
 512         mpc83xx_spi->count -= 1;
 513         if (mpc83xx_spi->count) {
 514                 u32 word = mpc83xx_spi->get_tx(mpc83xx_spi);
 515                 mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word);
 516         } else {
 517                 complete(&mpc83xx_spi->done);
 518         }
 519
 520         /* Clear the events */
 521         mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, event);
 522
 523         return ret;
 524 }
 525 static int mpc83xx_spi_transfer(struct spi_device *spi,
 526                                 struct spi_message *m)
 527 {
 528         struct mpc83xx_spi *mpc83xx_spi = spi_master_get_devdata(spi->master);
 529         unsigned long flags;
 530
 531         m->actual_length = 0;
 532         m->status = -EINPROGRESS;
 533
 534         spin_lock_irqsave(&mpc83xx_spi->lock, flags);
 535         list_add_tail(&m->queue, &mpc83xx_spi->queue);
 536         queue_work(mpc83xx_spi->workqueue, &mpc83xx_spi->work);
 537         spin_unlock_irqrestore(&mpc83xx_spi->lock, flags);
 538
 539         return 0;
 540 }
 541
 542
 543 static void mpc83xx_spi_cleanup(struct spi_device *spi)
 544 {
 545         kfree(spi->controller_state);
 546 }
 547
 548 static struct spi_master * __devinit
 549 mpc83xx_spi_probe(struct device *dev, struct resource *mem, unsigned int irq)
 550 {
 551         struct fsl_spi_platform_data *pdata = dev->platform_data;
 552         struct spi_master *master;
 553         struct mpc83xx_spi *mpc83xx_spi;
 554         u32 regval;
 555         int ret = 0;
 556
 557         master = spi_alloc_master(dev, sizeof(struct mpc83xx_spi));
 558         if (master == NULL) {
 559                 ret = -ENOMEM;
 560                 goto err;
 561         }
 562
 563         dev_set_drvdata(dev, master);
 564
 565         master->setup = mpc83xx_spi_setup;
 566         master->transfer = mpc83xx_spi_transfer;
 567         master->cleanup = mpc83xx_spi_cleanup;
 568
 569         mpc83xx_spi = spi_master_get_devdata(master);
 570         mpc83xx_spi->qe_mode = pdata->qe_mode;
 571         mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
 572         mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
 573         mpc83xx_spi->spibrg = pdata->sysclk;
 574
 575         mpc83xx_spi->rx_shift = 0;
 576         mpc83xx_spi->tx_shift = 0;
 577         if (mpc83xx_spi->qe_mode) {
 578                 mpc83xx_spi->rx_shift = 16;
 579                 mpc83xx_spi->tx_shift = 24;
 580         }
 581
 582         init_completion(&mpc83xx_spi->done);
 583
 584         mpc83xx_spi->base = ioremap(mem->start, mem->end - mem->start + 1);
 585         if (mpc83xx_spi->base == NULL) {
 586                 ret = -ENOMEM;
 587                 goto put_master;
 588         }
 589
 590         mpc83xx_spi->irq = irq;
 591
 592         /* Register for SPI Interrupt */
 593         ret = request_irq(mpc83xx_spi->irq, mpc83xx_spi_irq,
 594                           0, "mpc83xx_spi", mpc83xx_spi);
 595
 596         if (ret != 0)
 597                 goto unmap_io;
 598
 599         master->bus_num = pdata->bus_num;
 600         master->num_chipselect = pdata->max_chipselect;
 601
 602         /* SPI controller initializations */
 603         mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
 604         mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
 605         mpc83xx_spi_write_reg(&mpc83xx_spi->base->command, 0);
 606         mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, 0xffffffff);
 607
 608         /* Enable SPI interface */
 609         regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
 610         if (pdata->qe_mode)
 611                 regval |= SPMODE_OP;
 612
 613         mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
 614         spin_lock_init(&mpc83xx_spi->lock);
 615         init_completion(&mpc83xx_spi->done);
 616         INIT_WORK(&mpc83xx_spi->work, mpc83xx_spi_work);
 617         INIT_LIST_HEAD(&mpc83xx_spi->queue);
 618
 619         mpc83xx_spi->workqueue = create_singlethread_workqueue(
 620                 dev_name(master->dev.parent));
 621         if (mpc83xx_spi->workqueue == NULL) {
 622                 ret = -EBUSY;
 623                 goto free_irq;
 624         }
 625
 626         ret = spi_register_master(master);
 627         if (ret < 0)
 628                 goto unreg_master;
 629
 630         printk(KERN_INFO
 631                "%s: MPC83xx SPI Controller driver at 0x%p (irq = %d)\n",
 632                dev_name(dev), mpc83xx_spi->base, mpc83xx_spi->irq);
 633
 634         return master;
 635
 636 unreg_master:
 637         destroy_workqueue(mpc83xx_spi->workqueue);
 638 free_irq:
 639         free_irq(mpc83xx_spi->irq, mpc83xx_spi);
 640 unmap_io:
 641         iounmap(mpc83xx_spi->base);
 642 put_master:
 643         spi_master_put(master);
 644 err:
 645         return ERR_PTR(ret);
 646 }
 647
 648 static int __devexit mpc83xx_spi_remove(struct device *dev)
 649 {
 650         struct mpc83xx_spi *mpc83xx_spi;
 651         struct spi_master *master;
 652
 653         master = dev_get_drvdata(dev);
 654         mpc83xx_spi = spi_master_get_devdata(master);
 655
 656         flush_workqueue(mpc83xx_spi->workqueue);
 657         destroy_workqueue(mpc83xx_spi->workqueue);
 658         spi_unregister_master(master);
 659
 660         free_irq(mpc83xx_spi->irq, mpc83xx_spi);
 661         iounmap(mpc83xx_spi->base);
 662
 663         return 0;
 664 }
 665
 666 struct mpc83xx_spi_probe_info {
 667         struct fsl_spi_platform_data pdata;
 668         int *gpios;
 669         bool *alow_flags;
 670 };
 671
 672 static struct mpc83xx_spi_probe_info *
 673 to_of_pinfo(struct fsl_spi_platform_data *pdata)
 674 {
 675         return container_of(pdata, struct mpc83xx_spi_probe_info, pdata);
 676 }
 677
 678 static void mpc83xx_spi_cs_control(struct spi_device *spi, bool on)
 679 {
 680         struct device *dev = spi->dev.parent;
 681         struct mpc83xx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
 682         u16 cs = spi->chip_select;
 683         int gpio = pinfo->gpios[cs];
 684         bool alow = pinfo->alow_flags[cs];
 685
 686         gpio_set_value(gpio, on ^ alow);
 687 }
 688
 689 static int of_mpc83xx_spi_get_chipselects(struct device *dev)
 690 {
 691         struct device_node *np = dev_archdata_get_node(&dev->archdata);
 692         struct fsl_spi_platform_data *pdata = dev->platform_data;
 693         struct mpc83xx_spi_probe_info *pinfo = to_of_pinfo(pdata);
 694         unsigned int ngpios;
 695         int i = 0;
 696         int ret;
 697
 698         ngpios = of_gpio_count(np);
 699         if (!ngpios) {
 700                 /*
 701                  * SPI w/o chip-select line. One SPI device is still permitted
 702                  * though.
 703                  */
 704                 pdata->max_chipselect = 1;
 705                 return 0;
 706         }
 707
 708         pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
 709         if (!pinfo->gpios)
 710                 return -ENOMEM;
 711         memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
 712
 713         pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
 714                                     GFP_KERNEL);
 715         if (!pinfo->alow_flags) {
 716                 ret = -ENOMEM;
 717                 goto err_alloc_flags;
 718         }
 719
 720         for (; i < ngpios; i++) {
 721                 int gpio;
 722                 enum of_gpio_flags flags;
 723
 724                 gpio = of_get_gpio_flags(np, i, &flags);
 725                 if (!gpio_is_valid(gpio)) {
 726                         dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
 727                         goto err_loop;
 728                 }
 729
 730                 ret = gpio_request(gpio, dev_name(dev));
 731                 if (ret) {
 732                         dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
 733                         goto err_loop;
 734                 }
 735
 736                 pinfo->gpios[i] = gpio;
 737                 pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
 738
 739                 ret = gpio_direction_output(pinfo->gpios[i],
 740                                             pinfo->alow_flags[i]);
 741                 if (ret) {
 742                         dev_err(dev, "can't set output direction for gpio "
 743                                 "#%d: %d\n", i, ret);
 744                         goto err_loop;
 745                 }
 746         }
 747
 748         pdata->max_chipselect = ngpios;
 749         pdata->cs_control = mpc83xx_spi_cs_control;
 750
 751         return 0;
 752
 753 err_loop:
 754         while (i >= 0) {
 755                 if (gpio_is_valid(pinfo->gpios[i]))
 756                         gpio_free(pinfo->gpios[i]);
 757                 i--;
 758         }
 759
 760         kfree(pinfo->alow_flags);
 761         pinfo->alow_flags = NULL;
 762 err_alloc_flags:
 763         kfree(pinfo->gpios);
 764         pinfo->gpios = NULL;
 765         return ret;
 766 }
 767
 768 static int of_mpc83xx_spi_free_chipselects(struct device *dev)
 769 {
 770         struct fsl_spi_platform_data *pdata = dev->platform_data;
 771         struct mpc83xx_spi_probe_info *pinfo = to_of_pinfo(pdata);
 772         int i;
 773
 774         if (!pinfo->gpios)
 775                 return 0;
 776
 777         for (i = 0; i < pdata->max_chipselect; i++) {
 778                 if (gpio_is_valid(pinfo->gpios[i]))
 779                         gpio_free(pinfo->gpios[i]);
 780         }
 781
 782         kfree(pinfo->gpios);
 783         kfree(pinfo->alow_flags);
 784         return 0;
 785 }
 786
 787 static int __devinit of_mpc83xx_spi_probe(struct of_device *ofdev,
 788                                           const struct of_device_id *ofid)
 789 {
 790         struct device *dev = &ofdev->dev;
 791         struct device_node *np = ofdev->node;
 792         struct mpc83xx_spi_probe_info *pinfo;
 793         struct fsl_spi_platform_data *pdata;
 794         struct spi_master *master;
 795         struct resource mem;
 796         struct resource irq;
 797         const void *prop;
 798         int ret = -ENOMEM;
 799
 800         pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
 801         if (!pinfo)
 802                 return -ENOMEM;
 803
 804         pdata = &pinfo->pdata;
 805         dev->platform_data = pdata;
 806
 807         /* Allocate bus num dynamically. */
 808         pdata->bus_num = -1;
 809
 810         /* SPI controller is either clocked from QE or SoC clock. */
 811         pdata->sysclk = get_brgfreq();
 812         if (pdata->sysclk == -1) {
 813                 pdata->sysclk = fsl_get_sys_freq();
 814                 if (pdata->sysclk == -1) {
 815                         ret = -ENODEV;
 816                         goto err_clk;
 817                 }
 818         }
 819
 820         prop = of_get_property(np, "mode", NULL);
 821         if (prop && !strcmp(prop, "cpu-qe"))
 822                 pdata->qe_mode = 1;
 823
 824         ret = of_mpc83xx_spi_get_chipselects(dev);
 825         if (ret)
 826                 goto err;
 827
 828         ret = of_address_to_resource(np, 0, &mem);
 829         if (ret)
 830                 goto err;
 831
 832         ret = of_irq_to_resource(np, 0, &irq);
 833         if (!ret) {
 834                 ret = -EINVAL;
 835                 goto err;
 836         }
 837
 838         master = mpc83xx_spi_probe(dev, &mem, irq.start);
 839         if (IS_ERR(master)) {
 840                 ret = PTR_ERR(master);
 841                 goto err;
 842         }
 843
 844         of_register_spi_devices(master, np);
 845
 846         return 0;
 847
 848 err:
 849         of_mpc83xx_spi_free_chipselects(dev);
 850 err_clk:
 851         kfree(pinfo);
 852         return ret;
 853 }
 854
 855 static int __devexit of_mpc83xx_spi_remove(struct of_device *ofdev)
 856 {
 857         int ret;
 858
 859         ret = mpc83xx_spi_remove(&ofdev->dev);
 860         if (ret)
 861                 return ret;
 862         of_mpc83xx_spi_free_chipselects(&ofdev->dev);
 863         return 0;
 864 }
 865
 866 static const struct of_device_id of_mpc83xx_spi_match[] = {
 867         { .compatible = "fsl,spi" },
 868         {},
 869 };
 870 MODULE_DEVICE_TABLE(of, of_mpc83xx_spi_match);
 871
 872 static struct of_platform_driver of_mpc83xx_spi_driver = {
 873         .name           = "mpc83xx_spi",
 874         .match_table    = of_mpc83xx_spi_match,
 875         .probe          = of_mpc83xx_spi_probe,
 876         .remove         = __devexit_p(of_mpc83xx_spi_remove),
 877 };
 878
 879 #ifdef CONFIG_MPC832x_RDB
 880 /*
 881  *                              XXX XXX XXX
 882  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
 883  * only. The driver should go away soon, since newer MPC8323E-RDB's device
 884  * tree can work with OpenFirmware driver. But for now we support old trees
 885  * as well.
 886  */
 887 static int __devinit plat_mpc83xx_spi_probe(struct platform_device *pdev)
 888 {
 889         struct resource *mem;
 890         unsigned int irq;
 891         struct spi_master *master;
 892
 893         if (!pdev->dev.platform_data)
 894                 return -EINVAL;
 895
 896         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 897         if (!mem)
 898                 return -EINVAL;
 899
 900         irq = platform_get_irq(pdev, 0);
 901         if (!irq)
 902                 return -EINVAL;
 903
 904         master = mpc83xx_spi_probe(&pdev->dev, mem, irq);
 905         if (IS_ERR(master))
 906                 return PTR_ERR(master);
 907         return 0;
 908 }
 909
 910 static int __devexit plat_mpc83xx_spi_remove(struct platform_device *pdev)
 911 {
 912         return mpc83xx_spi_remove(&pdev->dev);
 913 }
 914
 915 MODULE_ALIAS("platform:mpc83xx_spi");
 916 static struct platform_driver mpc83xx_spi_driver = {
 917         .probe = plat_mpc83xx_spi_probe,
 918         .remove = __exit_p(plat_mpc83xx_spi_remove),
 919         .driver = {
 920                 .name = "mpc83xx_spi",
 921                 .owner = THIS_MODULE,
 922         },
 923 };
 924
 925 static bool legacy_driver_failed;
 926
 927 static void __init legacy_driver_register(void)
 928 {
 929         legacy_driver_failed = platform_driver_register(&mpc83xx_spi_driver);
 930 }
 931
 932 static void __exit legacy_driver_unregister(void)
 933 {
 934         if (legacy_driver_failed)
 935                 return;
 936         platform_driver_unregister(&mpc83xx_spi_driver);
 937 }
 938 #else
 939 static void __init legacy_driver_register(void) {}
 940 static void __exit legacy_driver_unregister(void) {}
 941 #endif /* CONFIG_MPC832x_RDB */
 942
 943 static int __init mpc83xx_spi_init(void)
 944 {
 945         legacy_driver_register();
 946         return of_register_platform_driver(&of_mpc83xx_spi_driver);
 947 }
 948
 949 static void __exit mpc83xx_spi_exit(void)
 950 {
 951         of_unregister_platform_driver(&of_mpc83xx_spi_driver);
 952         legacy_driver_unregister();
 953 }
 954
 955 module_init(mpc83xx_spi_init);
 956 module_exit(mpc83xx_spi_exit);
 957
 958 MODULE_AUTHOR("Kumar Gala");
 959 MODULE_DESCRIPTION("Simple MPC83xx SPI Driver");
 960 MODULE_LICENSE("GPL");