drivers/spi/spi_fsl_spi.c

   1 /*
   2  * Freescale SPI controller driver.
   3  *
   4  * Maintainer: Kumar Gala
   5  *
   6  * Copyright (C) 2006 Polycom, Inc.
   7  * Copyright 2010 Freescale Semiconductor, Inc.
   8  *
   9  * CPM SPI and QE buffer descriptors mode support:
  10  * Copyright (c) 2009  MontaVista Software, Inc.
  11  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
  12  *
  13  * This program is free software; you can redistribute  it and/or modify it
  14  * under  the terms of  the GNU General  Public License as published by the
  15  * Free Software Foundation;  either version 2 of the  License, or (at your
  16  * option) any later version.
  17  */
  18 #include <linux/module.h>
  19 #include <linux/types.h>
  20 #include <linux/kernel.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/delay.h>
  23 #include <linux/irq.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/dma-mapping.h>
  29 #include <linux/mm.h>
  30 #include <linux/mutex.h>
  31 #include <linux/of.h>
  32 #include <linux/of_platform.h>
  33 #include <linux/gpio.h>
  34 #include <linux/of_gpio.h>
  35
  36 #include <sysdev/fsl_soc.h>
  37 #include <asm/cpm.h>
  38 #include <asm/qe.h>
  39
  40 #include "spi_fsl_lib.h"
  41
  42 /* CPM1 and CPM2 are mutually exclusive. */
  43 #ifdef CONFIG_CPM1
  44 #include <asm/cpm1.h>
  45 #define CPM_SPI_CMD mk_cr_cmd(CPM_CR_CH_SPI, 0)
  46 #else
  47 #include <asm/cpm2.h>
  48 #define CPM_SPI_CMD mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK, 0, 0)
  49 #endif
  50
  51 /* SPI Controller registers */
  52 struct fsl_spi_reg {
  53         u8 res1[0x20];
  54         __be32 mode;
  55         __be32 event;
  56         __be32 mask;
  57         __be32 command;
  58         __be32 transmit;
  59         __be32 receive;
  60 };
  61
  62 /* SPI Controller mode register definitions */
  63 #define SPMODE_LOOP             (1 << 30)
  64 #define SPMODE_CI_INACTIVEHIGH  (1 << 29)
  65 #define SPMODE_CP_BEGIN_EDGECLK (1 << 28)
  66 #define SPMODE_DIV16            (1 << 27)
  67 #define SPMODE_REV              (1 << 26)
  68 #define SPMODE_MS               (1 << 25)
  69 #define SPMODE_ENABLE           (1 << 24)
  70 #define SPMODE_LEN(x)           ((x) << 20)
  71 #define SPMODE_PM(x)            ((x) << 16)
  72 #define SPMODE_OP               (1 << 14)
  73 #define SPMODE_CG(x)            ((x) << 7)
  74
  75 /*
  76  * Default for SPI Mode:
  77  *      SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk
  78  */
  79 #define SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \
  80                          SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf))
  81
  82 /* SPIE register values */
  83 #define SPIE_NE         0x00000200      /* Not empty */
  84 #define SPIE_NF         0x00000100      /* Not full */
  85
  86 /* SPIM register values */
  87 #define SPIM_NE         0x00000200      /* Not empty */
  88 #define SPIM_NF         0x00000100      /* Not full */
  89
  90 #define SPIE_TXB        0x00000200      /* Last char is written to tx fifo */
  91 #define SPIE_RXB        0x00000100      /* Last char is written to rx buf */
  92
  93 /* SPCOM register values */
  94 #define SPCOM_STR       (1 << 23)       /* Start transmit */
  95
  96 #define SPI_PRAM_SIZE   0x100
  97 #define SPI_MRBLR       ((unsigned int)PAGE_SIZE)
  98
  99 static void *fsl_dummy_rx;
 100 static DEFINE_MUTEX(fsl_dummy_rx_lock);
 101 static int fsl_dummy_rx_refcnt;
 102
 103 static void fsl_spi_change_mode(struct spi_device *spi)
 104 {
 105         struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
 106         struct spi_mpc8xxx_cs *cs = spi->controller_state;
 107         struct fsl_spi_reg *reg_base = mspi->reg_base;
 108         __be32 __iomem *mode = &reg_base->mode;
 109         unsigned long flags;
 110
 111         if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
 112                 return;
 113
 114         /* Turn off IRQs locally to minimize time that SPI is disabled. */
 115         local_irq_save(flags);
 116
 117         /* Turn off SPI unit prior changing mode */
 118         mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
 119
 120         /* When in CPM mode, we need to reinit tx and rx. */
 121         if (mspi->flags & SPI_CPM_MODE) {
 122                 if (mspi->flags & SPI_QE) {
 123                         qe_issue_cmd(QE_INIT_TX_RX, mspi->subblock,
 124                                      QE_CR_PROTOCOL_UNSPECIFIED, 0);
 125                 } else {
 126                         cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX);
 127                         if (mspi->flags & SPI_CPM1) {
 128                                 out_be16(&mspi->pram->rbptr,
 129                                          in_be16(&mspi->pram->rbase));
 130                                 out_be16(&mspi->pram->tbptr,
 131                                          in_be16(&mspi->pram->tbase));
 132                         }
 133                 }
 134         }
 135         mpc8xxx_spi_write_reg(mode, cs->hw_mode);
 136         local_irq_restore(flags);
 137 }
 138
 139 static void fsl_spi_chipselect(struct spi_device *spi, int value)
 140 {
 141         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
 142         struct fsl_spi_platform_data *pdata = spi->dev.parent->platform_data;
 143         bool pol = spi->mode & SPI_CS_HIGH;
 144         struct spi_mpc8xxx_cs   *cs = spi->controller_state;
 145
 146         if (value == BITBANG_CS_INACTIVE) {
 147                 if (pdata->cs_control)
 148                         pdata->cs_control(spi, !pol);
 149         }
 150
 151         if (value == BITBANG_CS_ACTIVE) {
 152                 mpc8xxx_spi->rx_shift = cs->rx_shift;
 153                 mpc8xxx_spi->tx_shift = cs->tx_shift;
 154                 mpc8xxx_spi->get_rx = cs->get_rx;
 155                 mpc8xxx_spi->get_tx = cs->get_tx;
 156
 157                 fsl_spi_change_mode(spi);
 158
 159                 if (pdata->cs_control)
 160                         pdata->cs_control(spi, pol);
 161         }
 162 }
 163
 164 static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
 165                                 struct spi_device *spi,
 166                                 struct mpc8xxx_spi *mpc8xxx_spi,
 167                                 int bits_per_word)
 168 {
 169         cs->rx_shift = 0;
 170         cs->tx_shift = 0;
 171         if (bits_per_word <= 8) {
 172                 cs->get_rx = mpc8xxx_spi_rx_buf_u8;
 173                 cs->get_tx = mpc8xxx_spi_tx_buf_u8;
 174                 if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
 175                         cs->rx_shift = 16;
 176                         cs->tx_shift = 24;
 177                 }
 178         } else if (bits_per_word <= 16) {
 179                 cs->get_rx = mpc8xxx_spi_rx_buf_u16;
 180                 cs->get_tx = mpc8xxx_spi_tx_buf_u16;
 181                 if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
 182                         cs->rx_shift = 16;
 183                         cs->tx_shift = 16;
 184                 }
 185         } else if (bits_per_word <= 32) {
 186                 cs->get_rx = mpc8xxx_spi_rx_buf_u32;
 187                 cs->get_tx = mpc8xxx_spi_tx_buf_u32;
 188         } else
 189                 return -EINVAL;
 190
 191         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE &&
 192             spi->mode & SPI_LSB_FIRST) {
 193                 cs->tx_shift = 0;
 194                 if (bits_per_word <= 8)
 195                         cs->rx_shift = 8;
 196                 else
 197                         cs->rx_shift = 0;
 198         }
 199         mpc8xxx_spi->rx_shift = cs->rx_shift;
 200         mpc8xxx_spi->tx_shift = cs->tx_shift;
 201         mpc8xxx_spi->get_rx = cs->get_rx;
 202         mpc8xxx_spi->get_tx = cs->get_tx;
 203
 204         return bits_per_word;
 205 }
 206
 207 static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
 208                                 struct spi_device *spi,
 209                                 int bits_per_word)
 210 {
 211         /* QE uses Little Endian for words > 8
 212          * so transform all words > 8 into 8 bits
 213          * Unfortnatly that doesn't work for LSB so
 214          * reject these for now */
 215         /* Note: 32 bits word, LSB works iff
 216          * tfcr/rfcr is set to CPMFCR_GBL */
 217         if (spi->mode & SPI_LSB_FIRST &&
 218             bits_per_word > 8)
 219                 return -EINVAL;
 220         if (bits_per_word > 8)
 221                 return 8; /* pretend its 8 bits */
 222         return bits_per_word;
 223 }
 224
 225 static int fsl_spi_setup_transfer(struct spi_device *spi,
 226                                         struct spi_transfer *t)
 227 {
 228         struct mpc8xxx_spi *mpc8xxx_spi;
 229         int bits_per_word = 0;
 230         u8 pm;
 231         u32 hz = 0;
 232         struct spi_mpc8xxx_cs   *cs = spi->controller_state;
 233
 234         mpc8xxx_spi = spi_master_get_devdata(spi->master);
 235
 236         if (t) {
 237                 bits_per_word = t->bits_per_word;
 238                 hz = t->speed_hz;
 239         }
 240
 241         /* spi_transfer level calls that work per-word */
 242         if (!bits_per_word)
 243                 bits_per_word = spi->bits_per_word;
 244
 245         /* Make sure its a bit width we support [4..16, 32] */
 246         if ((bits_per_word < 4)
 247             || ((bits_per_word > 16) && (bits_per_word != 32)))
 248                 return -EINVAL;
 249
 250         if (!hz)
 251                 hz = spi->max_speed_hz;
 252
 253         if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
 254                 bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
 255                                                            mpc8xxx_spi,
 256                                                            bits_per_word);
 257         else if (mpc8xxx_spi->flags & SPI_QE)
 258                 bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
 259                                                           bits_per_word);
 260
 261         if (bits_per_word < 0)
 262                 return bits_per_word;
 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 ((mpc8xxx_spi->spibrg / hz) > 64) {
 276                 cs->hw_mode |= SPMODE_DIV16;
 277                 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
 278
 279                 WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
 280                           "Will use %d Hz instead.\n", dev_name(&spi->dev),
 281                           hz, mpc8xxx_spi->spibrg / 1024);
 282                 if (pm > 16)
 283                         pm = 16;
 284         } else {
 285                 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
 286         }
 287         if (pm)
 288                 pm--;
 289
 290         cs->hw_mode |= SPMODE_PM(pm);
 291
 292         fsl_spi_change_mode(spi);
 293         return 0;
 294 }
 295
 296 static void fsl_spi_cpm_bufs_start(struct mpc8xxx_spi *mspi)
 297 {
 298         struct cpm_buf_desc __iomem *tx_bd = mspi->tx_bd;
 299         struct cpm_buf_desc __iomem *rx_bd = mspi->rx_bd;
 300         unsigned int xfer_len = min(mspi->count, SPI_MRBLR);
 301         unsigned int xfer_ofs;
 302         struct fsl_spi_reg *reg_base = mspi->reg_base;
 303
 304         xfer_ofs = mspi->xfer_in_progress->len - mspi->count;
 305
 306         if (mspi->rx_dma == mspi->dma_dummy_rx)
 307                 out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma);
 308         else
 309                 out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma + xfer_ofs);
 310         out_be16(&rx_bd->cbd_datlen, 0);
 311         out_be16(&rx_bd->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT | BD_SC_WRAP);
 312
 313         if (mspi->tx_dma == mspi->dma_dummy_tx)
 314                 out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma);
 315         else
 316                 out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma + xfer_ofs);
 317         out_be16(&tx_bd->cbd_datlen, xfer_len);
 318         out_be16(&tx_bd->cbd_sc, BD_SC_READY | BD_SC_INTRPT | BD_SC_WRAP |
 319                                  BD_SC_LAST);
 320
 321         /* start transfer */
 322         mpc8xxx_spi_write_reg(&reg_base->command, SPCOM_STR);
 323 }
 324
 325 static int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi,
 326                                 struct spi_transfer *t, bool is_dma_mapped)
 327 {
 328         struct device *dev = mspi->dev;
 329         struct fsl_spi_reg *reg_base = mspi->reg_base;
 330
 331         if (is_dma_mapped) {
 332                 mspi->map_tx_dma = 0;
 333                 mspi->map_rx_dma = 0;
 334         } else {
 335                 mspi->map_tx_dma = 1;
 336                 mspi->map_rx_dma = 1;
 337         }
 338
 339         if (!t->tx_buf) {
 340                 mspi->tx_dma = mspi->dma_dummy_tx;
 341                 mspi->map_tx_dma = 0;
 342         }
 343
 344         if (!t->rx_buf) {
 345                 mspi->rx_dma = mspi->dma_dummy_rx;
 346                 mspi->map_rx_dma = 0;
 347         }
 348
 349         if (mspi->map_tx_dma) {
 350                 void *nonconst_tx = (void *)mspi->tx; /* shut up gcc */
 351
 352                 mspi->tx_dma = dma_map_single(dev, nonconst_tx, t->len,
 353                                               DMA_TO_DEVICE);
 354                 if (dma_mapping_error(dev, mspi->tx_dma)) {
 355                         dev_err(dev, "unable to map tx dma\n");
 356                         return -ENOMEM;
 357                 }
 358         } else if (t->tx_buf) {
 359                 mspi->tx_dma = t->tx_dma;
 360         }
 361
 362         if (mspi->map_rx_dma) {
 363                 mspi->rx_dma = dma_map_single(dev, mspi->rx, t->len,
 364                                               DMA_FROM_DEVICE);
 365                 if (dma_mapping_error(dev, mspi->rx_dma)) {
 366                         dev_err(dev, "unable to map rx dma\n");
 367                         goto err_rx_dma;
 368                 }
 369         } else if (t->rx_buf) {
 370                 mspi->rx_dma = t->rx_dma;
 371         }
 372
 373         /* enable rx ints */
 374         mpc8xxx_spi_write_reg(&reg_base->mask, SPIE_RXB);
 375
 376         mspi->xfer_in_progress = t;
 377         mspi->count = t->len;
 378
 379         /* start CPM transfers */
 380         fsl_spi_cpm_bufs_start(mspi);
 381
 382         return 0;
 383
 384 err_rx_dma:
 385         if (mspi->map_tx_dma)
 386                 dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
 387         return -ENOMEM;
 388 }
 389
 390 static void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi)
 391 {
 392         struct device *dev = mspi->dev;
 393         struct spi_transfer *t = mspi->xfer_in_progress;
 394
 395         if (mspi->map_tx_dma)
 396                 dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
 397         if (mspi->map_rx_dma)
 398                 dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE);
 399         mspi->xfer_in_progress = NULL;
 400 }
 401
 402 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
 403                                 struct spi_transfer *t, unsigned int len)
 404 {
 405         u32 word;
 406         struct fsl_spi_reg *reg_base = mspi->reg_base;
 407
 408         mspi->count = len;
 409
 410         /* enable rx ints */
 411         mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
 412
 413         /* transmit word */
 414         word = mspi->get_tx(mspi);
 415         mpc8xxx_spi_write_reg(&reg_base->transmit, word);
 416
 417         return 0;
 418 }
 419
 420 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
 421                             bool is_dma_mapped)
 422 {
 423         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
 424         struct fsl_spi_reg *reg_base;
 425         unsigned int len = t->len;
 426         u8 bits_per_word;
 427         int ret;
 428
 429         reg_base = mpc8xxx_spi->reg_base;
 430         bits_per_word = spi->bits_per_word;
 431         if (t->bits_per_word)
 432                 bits_per_word = t->bits_per_word;
 433
 434         if (bits_per_word > 8) {
 435                 /* invalid length? */
 436                 if (len & 1)
 437                         return -EINVAL;
 438                 len /= 2;
 439         }
 440         if (bits_per_word > 16) {
 441                 /* invalid length? */
 442                 if (len & 1)
 443                         return -EINVAL;
 444                 len /= 2;
 445         }
 446
 447         mpc8xxx_spi->tx = t->tx_buf;
 448         mpc8xxx_spi->rx = t->rx_buf;
 449
 450         INIT_COMPLETION(mpc8xxx_spi->done);
 451
 452         if (mpc8xxx_spi->flags & SPI_CPM_MODE)
 453                 ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
 454         else
 455                 ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
 456         if (ret)
 457                 return ret;
 458
 459         wait_for_completion(&mpc8xxx_spi->done);
 460
 461         /* disable rx ints */
 462         mpc8xxx_spi_write_reg(&reg_base->mask, 0);
 463
 464         if (mpc8xxx_spi->flags & SPI_CPM_MODE)
 465                 fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
 466
 467         return mpc8xxx_spi->count;
 468 }
 469
 470 static void fsl_spi_do_one_msg(struct spi_message *m)
 471 {
 472         struct spi_device *spi = m->spi;
 473         struct spi_transfer *t;
 474         unsigned int cs_change;
 475         const int nsecs = 50;
 476         int status;
 477
 478         cs_change = 1;
 479         status = 0;
 480         list_for_each_entry(t, &m->transfers, transfer_list) {
 481                 if (t->bits_per_word || t->speed_hz) {
 482                         /* Don't allow changes if CS is active */
 483                         status = -EINVAL;
 484
 485                         if (cs_change)
 486                                 status = fsl_spi_setup_transfer(spi, t);
 487                         if (status < 0)
 488                                 break;
 489                 }
 490
 491                 if (cs_change) {
 492                         fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
 493                         ndelay(nsecs);
 494                 }
 495                 cs_change = t->cs_change;
 496                 if (t->len)
 497                         status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
 498                 if (status) {
 499                         status = -EMSGSIZE;
 500                         break;
 501                 }
 502                 m->actual_length += t->len;
 503
 504                 if (t->delay_usecs)
 505                         udelay(t->delay_usecs);
 506
 507                 if (cs_change) {
 508                         ndelay(nsecs);
 509                         fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
 510                         ndelay(nsecs);
 511                 }
 512         }
 513
 514         m->status = status;
 515         m->complete(m->context);
 516
 517         if (status || !cs_change) {
 518                 ndelay(nsecs);
 519                 fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
 520         }
 521
 522         fsl_spi_setup_transfer(spi, NULL);
 523 }
 524
 525 static int fsl_spi_setup(struct spi_device *spi)
 526 {
 527         struct mpc8xxx_spi *mpc8xxx_spi;
 528         struct fsl_spi_reg *reg_base;
 529         int retval;
 530         u32 hw_mode;
 531         struct spi_mpc8xxx_cs   *cs = spi->controller_state;
 532
 533         if (!spi->max_speed_hz)
 534                 return -EINVAL;
 535
 536         if (!cs) {
 537                 cs = kzalloc(sizeof *cs, GFP_KERNEL);
 538                 if (!cs)
 539                         return -ENOMEM;
 540                 spi->controller_state = cs;
 541         }
 542         mpc8xxx_spi = spi_master_get_devdata(spi->master);
 543
 544         reg_base = mpc8xxx_spi->reg_base;
 545
 546         hw_mode = cs->hw_mode; /* Save original settings */
 547         cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
 548         /* mask out bits we are going to set */
 549         cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
 550                          | SPMODE_REV | SPMODE_LOOP);
 551
 552         if (spi->mode & SPI_CPHA)
 553                 cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
 554         if (spi->mode & SPI_CPOL)
 555                 cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
 556         if (!(spi->mode & SPI_LSB_FIRST))
 557                 cs->hw_mode |= SPMODE_REV;
 558         if (spi->mode & SPI_LOOP)
 559                 cs->hw_mode |= SPMODE_LOOP;
 560
 561         retval = fsl_spi_setup_transfer(spi, NULL);
 562         if (retval < 0) {
 563                 cs->hw_mode = hw_mode; /* Restore settings */
 564                 return retval;
 565         }
 566         return 0;
 567 }
 568
 569 static void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events)
 570 {
 571         u16 len;
 572         struct fsl_spi_reg *reg_base = mspi->reg_base;
 573
 574         dev_dbg(mspi->dev, "%s: bd datlen %d, count %d\n", __func__,
 575                 in_be16(&mspi->rx_bd->cbd_datlen), mspi->count);
 576
 577         len = in_be16(&mspi->rx_bd->cbd_datlen);
 578         if (len > mspi->count) {
 579                 WARN_ON(1);
 580                 len = mspi->count;
 581         }
 582
 583         /* Clear the events */
 584         mpc8xxx_spi_write_reg(&reg_base->event, events);
 585
 586         mspi->count -= len;
 587         if (mspi->count)
 588                 fsl_spi_cpm_bufs_start(mspi);
 589         else
 590                 complete(&mspi->done);
 591 }
 592
 593 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
 594 {
 595         struct fsl_spi_reg *reg_base = mspi->reg_base;
 596
 597         /* We need handle RX first */
 598         if (events & SPIE_NE) {
 599                 u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
 600
 601                 if (mspi->rx)
 602                         mspi->get_rx(rx_data, mspi);
 603         }
 604
 605         if ((events & SPIE_NF) == 0)
 606                 /* spin until TX is done */
 607                 while (((events =
 608                         mpc8xxx_spi_read_reg(&reg_base->event)) &
 609                                                 SPIE_NF) == 0)
 610                         cpu_relax();
 611
 612         /* Clear the events */
 613         mpc8xxx_spi_write_reg(&reg_base->event, events);
 614
 615         mspi->count -= 1;
 616         if (mspi->count) {
 617                 u32 word = mspi->get_tx(mspi);
 618
 619                 mpc8xxx_spi_write_reg(&reg_base->transmit, word);
 620         } else {
 621                 complete(&mspi->done);
 622         }
 623 }
 624
 625 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
 626 {
 627         struct mpc8xxx_spi *mspi = context_data;
 628         irqreturn_t ret = IRQ_NONE;
 629         u32 events;
 630         struct fsl_spi_reg *reg_base = mspi->reg_base;
 631
 632         /* Get interrupt events(tx/rx) */
 633         events = mpc8xxx_spi_read_reg(&reg_base->event);
 634         if (events)
 635                 ret = IRQ_HANDLED;
 636
 637         dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
 638
 639         if (mspi->flags & SPI_CPM_MODE)
 640                 fsl_spi_cpm_irq(mspi, events);
 641         else
 642                 fsl_spi_cpu_irq(mspi, events);
 643
 644         return ret;
 645 }
 646
 647 static void *fsl_spi_alloc_dummy_rx(void)
 648 {
 649         mutex_lock(&fsl_dummy_rx_lock);
 650
 651         if (!fsl_dummy_rx)
 652                 fsl_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL);
 653         if (fsl_dummy_rx)
 654                 fsl_dummy_rx_refcnt++;
 655
 656         mutex_unlock(&fsl_dummy_rx_lock);
 657
 658         return fsl_dummy_rx;
 659 }
 660
 661 static void fsl_spi_free_dummy_rx(void)
 662 {
 663         mutex_lock(&fsl_dummy_rx_lock);
 664
 665         switch (fsl_dummy_rx_refcnt) {
 666         case 0:
 667                 WARN_ON(1);
 668                 break;
 669         case 1:
 670                 kfree(fsl_dummy_rx);
 671                 fsl_dummy_rx = NULL;
 672                 /* fall through */
 673         default:
 674                 fsl_dummy_rx_refcnt--;
 675                 break;
 676         }
 677
 678         mutex_unlock(&fsl_dummy_rx_lock);
 679 }
 680
 681 static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi)
 682 {
 683         struct device *dev = mspi->dev;
 684         struct device_node *np = dev->of_node;
 685         const u32 *iprop;
 686         int size;
 687         unsigned long spi_base_ofs;
 688         unsigned long pram_ofs = -ENOMEM;
 689
 690         /* Can't use of_address_to_resource(), QE muram isn't at 0. */
 691         iprop = of_get_property(np, "reg", &size);
 692
 693         /* QE with a fixed pram location? */
 694         if (mspi->flags & SPI_QE && iprop && size == sizeof(*iprop) * 4)
 695                 return cpm_muram_alloc_fixed(iprop[2], SPI_PRAM_SIZE);
 696
 697         /* QE but with a dynamic pram location? */
 698         if (mspi->flags & SPI_QE) {
 699                 pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
 700                 qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, mspi->subblock,
 701                                 QE_CR_PROTOCOL_UNSPECIFIED, pram_ofs);
 702                 return pram_ofs;
 703         }
 704
 705         /* CPM1 and CPM2 pram must be at a fixed addr. */
 706         if (!iprop || size != sizeof(*iprop) * 4)
 707                 return -ENOMEM;
 708
 709         spi_base_ofs = cpm_muram_alloc_fixed(iprop[2], 2);
 710         if (IS_ERR_VALUE(spi_base_ofs))
 711                 return -ENOMEM;
 712
 713         if (mspi->flags & SPI_CPM2) {
 714                 pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
 715                 if (!IS_ERR_VALUE(pram_ofs)) {
 716                         u16 __iomem *spi_base = cpm_muram_addr(spi_base_ofs);
 717
 718                         out_be16(spi_base, pram_ofs);
 719                 }
 720         } else {
 721                 struct spi_pram __iomem *pram = cpm_muram_addr(spi_base_ofs);
 722                 u16 rpbase = in_be16(&pram->rpbase);
 723
 724                 /* Microcode relocation patch applied? */
 725                 if (rpbase)
 726                         pram_ofs = rpbase;
 727                 else
 728                         return spi_base_ofs;
 729         }
 730
 731         cpm_muram_free(spi_base_ofs);
 732         return pram_ofs;
 733 }
 734
 735 static int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi)
 736 {
 737         struct device *dev = mspi->dev;
 738         struct device_node *np = dev->of_node;
 739         const u32 *iprop;
 740         int size;
 741         unsigned long pram_ofs;
 742         unsigned long bds_ofs;
 743
 744         if (!(mspi->flags & SPI_CPM_MODE))
 745                 return 0;
 746
 747         if (!fsl_spi_alloc_dummy_rx())
 748                 return -ENOMEM;
 749
 750         if (mspi->flags & SPI_QE) {
 751                 iprop = of_get_property(np, "cell-index", &size);
 752                 if (iprop && size == sizeof(*iprop))
 753                         mspi->subblock = *iprop;
 754
 755                 switch (mspi->subblock) {
 756                 default:
 757                         dev_warn(dev, "cell-index unspecified, assuming SPI1");
 758                         /* fall through */
 759                 case 0:
 760                         mspi->subblock = QE_CR_SUBBLOCK_SPI1;
 761                         break;
 762                 case 1:
 763                         mspi->subblock = QE_CR_SUBBLOCK_SPI2;
 764                         break;
 765                 }
 766         }
 767
 768         pram_ofs = fsl_spi_cpm_get_pram(mspi);
 769         if (IS_ERR_VALUE(pram_ofs)) {
 770                 dev_err(dev, "can't allocate spi parameter ram\n");
 771                 goto err_pram;
 772         }
 773
 774         bds_ofs = cpm_muram_alloc(sizeof(*mspi->tx_bd) +
 775                                   sizeof(*mspi->rx_bd), 8);
 776         if (IS_ERR_VALUE(bds_ofs)) {
 777                 dev_err(dev, "can't allocate bds\n");
 778                 goto err_bds;
 779         }
 780
 781         mspi->dma_dummy_tx = dma_map_single(dev, empty_zero_page, PAGE_SIZE,
 782                                             DMA_TO_DEVICE);
 783         if (dma_mapping_error(dev, mspi->dma_dummy_tx)) {
 784                 dev_err(dev, "unable to map dummy tx buffer\n");
 785                 goto err_dummy_tx;
 786         }
 787
 788         mspi->dma_dummy_rx = dma_map_single(dev, fsl_dummy_rx, SPI_MRBLR,
 789                                             DMA_FROM_DEVICE);
 790         if (dma_mapping_error(dev, mspi->dma_dummy_rx)) {
 791                 dev_err(dev, "unable to map dummy rx buffer\n");
 792                 goto err_dummy_rx;
 793         }
 794
 795         mspi->pram = cpm_muram_addr(pram_ofs);
 796
 797         mspi->tx_bd = cpm_muram_addr(bds_ofs);
 798         mspi->rx_bd = cpm_muram_addr(bds_ofs + sizeof(*mspi->tx_bd));
 799
 800         /* Initialize parameter ram. */
 801         out_be16(&mspi->pram->tbase, cpm_muram_offset(mspi->tx_bd));
 802         out_be16(&mspi->pram->rbase, cpm_muram_offset(mspi->rx_bd));
 803         out_8(&mspi->pram->tfcr, CPMFCR_EB | CPMFCR_GBL);
 804         out_8(&mspi->pram->rfcr, CPMFCR_EB | CPMFCR_GBL);
 805         out_be16(&mspi->pram->mrblr, SPI_MRBLR);
 806         out_be32(&mspi->pram->rstate, 0);
 807         out_be32(&mspi->pram->rdp, 0);
 808         out_be16(&mspi->pram->rbptr, 0);
 809         out_be16(&mspi->pram->rbc, 0);
 810         out_be32(&mspi->pram->rxtmp, 0);
 811         out_be32(&mspi->pram->tstate, 0);
 812         out_be32(&mspi->pram->tdp, 0);
 813         out_be16(&mspi->pram->tbptr, 0);
 814         out_be16(&mspi->pram->tbc, 0);
 815         out_be32(&mspi->pram->txtmp, 0);
 816
 817         return 0;
 818
 819 err_dummy_rx:
 820         dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
 821 err_dummy_tx:
 822         cpm_muram_free(bds_ofs);
 823 err_bds:
 824         cpm_muram_free(pram_ofs);
 825 err_pram:
 826         fsl_spi_free_dummy_rx();
 827         return -ENOMEM;
 828 }
 829
 830 static void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi)
 831 {
 832         struct device *dev = mspi->dev;
 833
 834         dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE);
 835         dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
 836         cpm_muram_free(cpm_muram_offset(mspi->tx_bd));
 837         cpm_muram_free(cpm_muram_offset(mspi->pram));
 838         fsl_spi_free_dummy_rx();
 839 }
 840
 841 static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
 842 {
 843         iounmap(mspi->reg_base);
 844         fsl_spi_cpm_free(mspi);
 845 }
 846
 847 static struct spi_master * __devinit fsl_spi_probe(struct device *dev,
 848                 struct resource *mem, unsigned int irq)
 849 {
 850         struct fsl_spi_platform_data *pdata = dev->platform_data;
 851         struct spi_master *master;
 852         struct mpc8xxx_spi *mpc8xxx_spi;
 853         struct fsl_spi_reg *reg_base;
 854         u32 regval;
 855         int ret = 0;
 856
 857         master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
 858         if (master == NULL) {
 859                 ret = -ENOMEM;
 860                 goto err;
 861         }
 862
 863         dev_set_drvdata(dev, master);
 864
 865         ret = mpc8xxx_spi_probe(dev, mem, irq);
 866         if (ret)
 867                 goto err_probe;
 868
 869         master->setup = fsl_spi_setup;
 870
 871         mpc8xxx_spi = spi_master_get_devdata(master);
 872         mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
 873         mpc8xxx_spi->spi_remove = fsl_spi_remove;
 874
 875
 876         ret = fsl_spi_cpm_init(mpc8xxx_spi);
 877         if (ret)
 878                 goto err_cpm_init;
 879
 880         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
 881                 mpc8xxx_spi->rx_shift = 16;
 882                 mpc8xxx_spi->tx_shift = 24;
 883         }
 884
 885         mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
 886         if (mpc8xxx_spi->reg_base == NULL) {
 887                 ret = -ENOMEM;
 888                 goto err_ioremap;
 889         }
 890
 891         /* Register for SPI Interrupt */
 892         ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
 893                           0, "fsl_spi", mpc8xxx_spi);
 894
 895         if (ret != 0)
 896                 goto free_irq;
 897
 898         reg_base = mpc8xxx_spi->reg_base;
 899
 900         /* SPI controller initializations */
 901         mpc8xxx_spi_write_reg(&reg_base->mode, 0);
 902         mpc8xxx_spi_write_reg(&reg_base->mask, 0);
 903         mpc8xxx_spi_write_reg(&reg_base->command, 0);
 904         mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
 905
 906         /* Enable SPI interface */
 907         regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
 908         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
 909                 regval |= SPMODE_OP;
 910
 911         mpc8xxx_spi_write_reg(&reg_base->mode, regval);
 912
 913         ret = spi_register_master(master);
 914         if (ret < 0)
 915                 goto unreg_master;
 916
 917         dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
 918                  mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
 919
 920         return master;
 921
 922 unreg_master:
 923         free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
 924 free_irq:
 925         iounmap(mpc8xxx_spi->reg_base);
 926 err_ioremap:
 927         fsl_spi_cpm_free(mpc8xxx_spi);
 928 err_cpm_init:
 929 err_probe:
 930         spi_master_put(master);
 931 err:
 932         return ERR_PTR(ret);
 933 }
 934
 935 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
 936 {
 937         struct device *dev = spi->dev.parent;
 938         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
 939         u16 cs = spi->chip_select;
 940         int gpio = pinfo->gpios[cs];
 941         bool alow = pinfo->alow_flags[cs];
 942
 943         gpio_set_value(gpio, on ^ alow);
 944 }
 945
 946 static int of_fsl_spi_get_chipselects(struct device *dev)
 947 {
 948         struct device_node *np = dev->of_node;
 949         struct fsl_spi_platform_data *pdata = dev->platform_data;
 950         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
 951         unsigned int ngpios;
 952         int i = 0;
 953         int ret;
 954
 955         ngpios = of_gpio_count(np);
 956         if (!ngpios) {
 957                 /*
 958                  * SPI w/o chip-select line. One SPI device is still permitted
 959                  * though.
 960                  */
 961                 pdata->max_chipselect = 1;
 962                 return 0;
 963         }
 964
 965         pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
 966         if (!pinfo->gpios)
 967                 return -ENOMEM;
 968         memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
 969
 970         pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
 971                                     GFP_KERNEL);
 972         if (!pinfo->alow_flags) {
 973                 ret = -ENOMEM;
 974                 goto err_alloc_flags;
 975         }
 976
 977         for (; i < ngpios; i++) {
 978                 int gpio;
 979                 enum of_gpio_flags flags;
 980
 981                 gpio = of_get_gpio_flags(np, i, &flags);
 982                 if (!gpio_is_valid(gpio)) {
 983                         dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
 984                         ret = gpio;
 985                         goto err_loop;
 986                 }
 987
 988                 ret = gpio_request(gpio, dev_name(dev));
 989                 if (ret) {
 990                         dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
 991                         goto err_loop;
 992                 }
 993
 994                 pinfo->gpios[i] = gpio;
 995                 pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
 996
 997                 ret = gpio_direction_output(pinfo->gpios[i],
 998                                             pinfo->alow_flags[i]);
 999                 if (ret) {
1000                         dev_err(dev, "can't set output direction for gpio "
1001                                 "#%d: %d\n", i, ret);
1002                         goto err_loop;
1003                 }
1004         }
1005
1006         pdata->max_chipselect = ngpios;
1007         pdata->cs_control = fsl_spi_cs_control;
1008
1009         return 0;
1010
1011 err_loop:
1012         while (i >= 0) {
1013                 if (gpio_is_valid(pinfo->gpios[i]))
1014                         gpio_free(pinfo->gpios[i]);
1015                 i--;
1016         }
1017
1018         kfree(pinfo->alow_flags);
1019         pinfo->alow_flags = NULL;
1020 err_alloc_flags:
1021         kfree(pinfo->gpios);
1022         pinfo->gpios = NULL;
1023         return ret;
1024 }
1025
1026 static int of_fsl_spi_free_chipselects(struct device *dev)
1027 {
1028         struct fsl_spi_platform_data *pdata = dev->platform_data;
1029         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
1030         int i;
1031
1032         if (!pinfo->gpios)
1033                 return 0;
1034
1035         for (i = 0; i < pdata->max_chipselect; i++) {
1036                 if (gpio_is_valid(pinfo->gpios[i]))
1037                         gpio_free(pinfo->gpios[i]);
1038         }
1039
1040         kfree(pinfo->gpios);
1041         kfree(pinfo->alow_flags);
1042         return 0;
1043 }
1044
1045 static int __devinit of_fsl_spi_probe(struct platform_device *ofdev,
1046                                         const struct of_device_id *ofid)
1047 {
1048         struct device *dev = &ofdev->dev;
1049         struct device_node *np = ofdev->dev.of_node;
1050         struct spi_master *master;
1051         struct resource mem;
1052         struct resource irq;
1053         int ret = -ENOMEM;
1054
1055         ret = of_mpc8xxx_spi_probe(ofdev, ofid);
1056         if (ret)
1057                 return ret;
1058
1059         ret = of_fsl_spi_get_chipselects(dev);
1060         if (ret)
1061                 goto err;
1062
1063         ret = of_address_to_resource(np, 0, &mem);
1064         if (ret)
1065                 goto err;
1066
1067         ret = of_irq_to_resource(np, 0, &irq);
1068         if (!ret) {
1069                 ret = -EINVAL;
1070                 goto err;
1071         }
1072
1073         master = fsl_spi_probe(dev, &mem, irq.start);
1074         if (IS_ERR(master)) {
1075                 ret = PTR_ERR(master);
1076                 goto err;
1077         }
1078
1079         return 0;
1080
1081 err:
1082         of_fsl_spi_free_chipselects(dev);
1083         return ret;
1084 }
1085
1086 static int __devexit of_fsl_spi_remove(struct platform_device *ofdev)
1087 {
1088         int ret;
1089
1090         ret = mpc8xxx_spi_remove(&ofdev->dev);
1091         if (ret)
1092                 return ret;
1093         of_fsl_spi_free_chipselects(&ofdev->dev);
1094         return 0;
1095 }
1096
1097 static const struct of_device_id of_fsl_spi_match[] = {
1098         { .compatible = "fsl,spi" },
1099         {}
1100 };
1101 MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
1102
1103 static struct of_platform_driver of_fsl_spi_driver = {
1104         .driver = {
1105                 .name = "fsl_spi",
1106                 .owner = THIS_MODULE,
1107                 .of_match_table = of_fsl_spi_match,
1108         },
1109         .probe          = of_fsl_spi_probe,
1110         .remove         = __devexit_p(of_fsl_spi_remove),
1111 };
1112
1113 #ifdef CONFIG_MPC832x_RDB
1114 /*
1115  * XXX XXX XXX
1116  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
1117  * only. The driver should go away soon, since newer MPC8323E-RDB's device
1118  * tree can work with OpenFirmware driver. But for now we support old trees
1119  * as well.
1120  */
1121 static int __devinit plat_mpc8xxx_spi_probe(struct platform_device *pdev)
1122 {
1123         struct resource *mem;
1124         int irq;
1125         struct spi_master *master;
1126
1127         if (!pdev->dev.platform_data)
1128                 return -EINVAL;
1129
1130         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1131         if (!mem)
1132                 return -EINVAL;
1133
1134         irq = platform_get_irq(pdev, 0);
1135         if (irq <= 0)
1136                 return -EINVAL;
1137
1138         master = fsl_spi_probe(&pdev->dev, mem, irq);
1139         if (IS_ERR(master))
1140                 return PTR_ERR(master);
1141         return 0;
1142 }
1143
1144 static int __devexit plat_mpc8xxx_spi_remove(struct platform_device *pdev)
1145 {
1146         return mpc8xxx_spi_remove(&pdev->dev);
1147 }
1148
1149 MODULE_ALIAS("platform:mpc8xxx_spi");
1150 static struct platform_driver mpc8xxx_spi_driver = {
1151         .probe = plat_mpc8xxx_spi_probe,
1152         .remove = __devexit_p(plat_mpc8xxx_spi_remove),
1153         .driver = {
1154                 .name = "mpc8xxx_spi",
1155                 .owner = THIS_MODULE,
1156         },
1157 };
1158
1159 static bool legacy_driver_failed;
1160
1161 static void __init legacy_driver_register(void)
1162 {
1163         legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
1164 }
1165
1166 static void __exit legacy_driver_unregister(void)
1167 {
1168         if (legacy_driver_failed)
1169                 return;
1170         platform_driver_unregister(&mpc8xxx_spi_driver);
1171 }
1172 #else
1173 static void __init legacy_driver_register(void) {}
1174 static void __exit legacy_driver_unregister(void) {}
1175 #endif /* CONFIG_MPC832x_RDB */
1176
1177 static int __init fsl_spi_init(void)
1178 {
1179         legacy_driver_register();
1180         return of_register_platform_driver(&of_fsl_spi_driver);
1181 }
1182 module_init(fsl_spi_init);
1183
1184 static void __exit fsl_spi_exit(void)
1185 {
1186         of_unregister_platform_driver(&of_fsl_spi_driver);
1187         legacy_driver_unregister();
1188 }
1189 module_exit(fsl_spi_exit);
1190
1191 MODULE_AUTHOR("Kumar Gala");
1192 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
1193 MODULE_LICENSE("GPL");