drivers/spi/spi-omap2-mcspi.c

   1 /*
   2  * OMAP2 McSPI controller driver
   3  *
   4  * Copyright (C) 2005, 2006 Nokia Corporation
   5  * Author:      Samuel Ortiz <samuel.ortiz@nokia.com> and
   6  *              Juha Yrj�l� <juha.yrjola@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  *
  22  */
  23
  24 #include <linux/kernel.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/module.h>
  27 #include <linux/device.h>
  28 #include <linux/delay.h>
  29 #include <linux/dma-mapping.h>
  30 #include <linux/dmaengine.h>
  31 #include <linux/omap-dma.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/err.h>
  34 #include <linux/clk.h>
  35 #include <linux/io.h>
  36 #include <linux/slab.h>
  37 #include <linux/pm_runtime.h>
  38 #include <linux/of.h>
  39 #include <linux/of_device.h>
  40 #include <linux/gcd.h>
  41
  42 #include <linux/spi/spi.h>
  43
  44 #include <linux/platform_data/spi-omap2-mcspi.h>
  45
  46 #define OMAP2_MCSPI_MAX_FREQ            48000000
  47 #define OMAP2_MCSPI_MAX_DIVIDER         4096
  48 #define OMAP2_MCSPI_MAX_FIFODEPTH       64
  49 #define OMAP2_MCSPI_MAX_FIFOWCNT        0xFFFF
  50 #define SPI_AUTOSUSPEND_TIMEOUT         2000
  51
  52 #define OMAP2_MCSPI_REVISION            0x00
  53 #define OMAP2_MCSPI_SYSSTATUS           0x14
  54 #define OMAP2_MCSPI_IRQSTATUS           0x18
  55 #define OMAP2_MCSPI_IRQENABLE           0x1c
  56 #define OMAP2_MCSPI_WAKEUPENABLE        0x20
  57 #define OMAP2_MCSPI_SYST                0x24
  58 #define OMAP2_MCSPI_MODULCTRL           0x28
  59 #define OMAP2_MCSPI_XFERLEVEL           0x7c
  60
  61 /* per-channel banks, 0x14 bytes each, first is: */
  62 #define OMAP2_MCSPI_CHCONF0             0x2c
  63 #define OMAP2_MCSPI_CHSTAT0             0x30
  64 #define OMAP2_MCSPI_CHCTRL0             0x34
  65 #define OMAP2_MCSPI_TX0                 0x38
  66 #define OMAP2_MCSPI_RX0                 0x3c
  67
  68 /* per-register bitmasks: */
  69 #define OMAP2_MCSPI_IRQSTATUS_EOW       BIT(17)
  70
  71 #define OMAP2_MCSPI_MODULCTRL_SINGLE    BIT(0)
  72 #define OMAP2_MCSPI_MODULCTRL_MS        BIT(2)
  73 #define OMAP2_MCSPI_MODULCTRL_STEST     BIT(3)
  74
  75 #define OMAP2_MCSPI_CHCONF_PHA          BIT(0)
  76 #define OMAP2_MCSPI_CHCONF_POL          BIT(1)
  77 #define OMAP2_MCSPI_CHCONF_CLKD_MASK    (0x0f << 2)
  78 #define OMAP2_MCSPI_CHCONF_EPOL         BIT(6)
  79 #define OMAP2_MCSPI_CHCONF_WL_MASK      (0x1f << 7)
  80 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY  BIT(12)
  81 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY  BIT(13)
  82 #define OMAP2_MCSPI_CHCONF_TRM_MASK     (0x03 << 12)
  83 #define OMAP2_MCSPI_CHCONF_DMAW         BIT(14)
  84 #define OMAP2_MCSPI_CHCONF_DMAR         BIT(15)
  85 #define OMAP2_MCSPI_CHCONF_DPE0         BIT(16)
  86 #define OMAP2_MCSPI_CHCONF_DPE1         BIT(17)
  87 #define OMAP2_MCSPI_CHCONF_IS           BIT(18)
  88 #define OMAP2_MCSPI_CHCONF_TURBO        BIT(19)
  89 #define OMAP2_MCSPI_CHCONF_FORCE        BIT(20)
  90 #define OMAP2_MCSPI_CHCONF_FFET         BIT(27)
  91 #define OMAP2_MCSPI_CHCONF_FFER         BIT(28)
  92 #define OMAP2_MCSPI_CHCONF_CLKG         BIT(29)
  93
  94 #define OMAP2_MCSPI_CHSTAT_RXS          BIT(0)
  95 #define OMAP2_MCSPI_CHSTAT_TXS          BIT(1)
  96 #define OMAP2_MCSPI_CHSTAT_EOT          BIT(2)
  97 #define OMAP2_MCSPI_CHSTAT_TXFFE        BIT(3)
  98
  99 #define OMAP2_MCSPI_CHCTRL_EN           BIT(0)
 100 #define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK  (0xff << 8)
 101
 102 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN   BIT(0)
 103
 104 /* We have 2 DMA channels per CS, one for RX and one for TX */
 105 struct omap2_mcspi_dma {
 106         struct dma_chan *dma_tx;
 107         struct dma_chan *dma_rx;
 108
 109         int dma_tx_sync_dev;
 110         int dma_rx_sync_dev;
 111
 112         struct completion dma_tx_completion;
 113         struct completion dma_rx_completion;
 114
 115         char dma_rx_ch_name[14];
 116         char dma_tx_ch_name[14];
 117 };
 118
 119 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 120  * cache operations; better heuristics consider wordsize and bitrate.
 121  */
 122 #define DMA_MIN_BYTES                   160
 123
 124
 125 /*
 126  * Used for context save and restore, structure members to be updated whenever
 127  * corresponding registers are modified.
 128  */
 129 struct omap2_mcspi_regs {
 130         u32 modulctrl;
 131         u32 wakeupenable;
 132         struct list_head cs;
 133 };
 134
 135 struct omap2_mcspi {
 136         struct spi_master       *master;
 137         /* Virtual base address of the controller */
 138         void __iomem            *base;
 139         unsigned long           phys;
 140         /* SPI1 has 4 channels, while SPI2 has 2 */
 141         struct omap2_mcspi_dma  *dma_channels;
 142         struct device           *dev;
 143         struct omap2_mcspi_regs ctx;
 144         int                     fifo_depth;
 145         unsigned int            pin_dir:1;
 146 };
 147
 148 struct omap2_mcspi_cs {
 149         void __iomem            *base;
 150         unsigned long           phys;
 151         int                     word_len;
 152         u16                     mode;
 153         struct list_head        node;
 154         /* Context save and restore shadow register */
 155         u32                     chconf0, chctrl0;
 156 };
 157
 158 static inline void mcspi_write_reg(struct spi_master *master,
 159                 int idx, u32 val)
 160 {
 161         struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 162
 163         writel_relaxed(val, mcspi->base + idx);
 164 }
 165
 166 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 167 {
 168         struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 169
 170         return readl_relaxed(mcspi->base + idx);
 171 }
 172
 173 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 174                 int idx, u32 val)
 175 {
 176         struct omap2_mcspi_cs   *cs = spi->controller_state;
 177
 178         writel_relaxed(val, cs->base +  idx);
 179 }
 180
 181 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 182 {
 183         struct omap2_mcspi_cs   *cs = spi->controller_state;
 184
 185         return readl_relaxed(cs->base + idx);
 186 }
 187
 188 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 189 {
 190         struct omap2_mcspi_cs *cs = spi->controller_state;
 191
 192         return cs->chconf0;
 193 }
 194
 195 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 196 {
 197         struct omap2_mcspi_cs *cs = spi->controller_state;
 198
 199         cs->chconf0 = val;
 200         mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 201         mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 202 }
 203
 204 static inline int mcspi_bytes_per_word(int word_len)
 205 {
 206         if (word_len <= 8)
 207                 return 1;
 208         else if (word_len <= 16)
 209                 return 2;
 210         else /* word_len <= 32 */
 211                 return 4;
 212 }
 213
 214 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 215                 int is_read, int enable)
 216 {
 217         u32 l, rw;
 218
 219         l = mcspi_cached_chconf0(spi);
 220
 221         if (is_read) /* 1 is read, 0 write */
 222                 rw = OMAP2_MCSPI_CHCONF_DMAR;
 223         else
 224                 rw = OMAP2_MCSPI_CHCONF_DMAW;
 225
 226         if (enable)
 227                 l |= rw;
 228         else
 229                 l &= ~rw;
 230
 231         mcspi_write_chconf0(spi, l);
 232 }
 233
 234 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 235 {
 236         struct omap2_mcspi_cs *cs = spi->controller_state;
 237         u32 l;
 238
 239         l = cs->chctrl0;
 240         if (enable)
 241                 l |= OMAP2_MCSPI_CHCTRL_EN;
 242         else
 243                 l &= ~OMAP2_MCSPI_CHCTRL_EN;
 244         cs->chctrl0 = l;
 245         mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 246         /* Flash post-writes */
 247         mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 248 }
 249
 250 static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 251 {
 252         u32 l;
 253
 254         l = mcspi_cached_chconf0(spi);
 255         if (cs_active)
 256                 l |= OMAP2_MCSPI_CHCONF_FORCE;
 257         else
 258                 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
 259
 260         mcspi_write_chconf0(spi, l);
 261 }
 262
 263 static void omap2_mcspi_set_master_mode(struct spi_master *master)
 264 {
 265         struct omap2_mcspi      *mcspi = spi_master_get_devdata(master);
 266         struct omap2_mcspi_regs *ctx = &mcspi->ctx;
 267         u32 l;
 268
 269         /*
 270          * Setup when switching from (reset default) slave mode
 271          * to single-channel master mode
 272          */
 273         l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 274         l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
 275         l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
 276         mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 277
 278         ctx->modulctrl = l;
 279 }
 280
 281 static void omap2_mcspi_set_fifo(const struct spi_device *spi,
 282                                 struct spi_transfer *t, int enable)
 283 {
 284         struct spi_master *master = spi->master;
 285         struct omap2_mcspi_cs *cs = spi->controller_state;
 286         struct omap2_mcspi *mcspi;
 287         unsigned int wcnt;
 288         int max_fifo_depth, fifo_depth, bytes_per_word;
 289         u32 chconf, xferlevel;
 290
 291         mcspi = spi_master_get_devdata(master);
 292
 293         chconf = mcspi_cached_chconf0(spi);
 294         if (enable) {
 295                 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
 296                 if (t->len % bytes_per_word != 0)
 297                         goto disable_fifo;
 298
 299                 if (t->rx_buf != NULL && t->tx_buf != NULL)
 300                         max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
 301                 else
 302                         max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
 303
 304                 fifo_depth = gcd(t->len, max_fifo_depth);
 305                 if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
 306                         goto disable_fifo;
 307
 308                 wcnt = t->len / bytes_per_word;
 309                 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
 310                         goto disable_fifo;
 311
 312                 xferlevel = wcnt << 16;
 313                 if (t->rx_buf != NULL) {
 314                         chconf |= OMAP2_MCSPI_CHCONF_FFER;
 315                         xferlevel |= (fifo_depth - 1) << 8;
 316                 }
 317                 if (t->tx_buf != NULL) {
 318                         chconf |= OMAP2_MCSPI_CHCONF_FFET;
 319                         xferlevel |= fifo_depth - 1;
 320                 }
 321
 322                 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
 323                 mcspi_write_chconf0(spi, chconf);
 324                 mcspi->fifo_depth = fifo_depth;
 325
 326                 return;
 327         }
 328
 329 disable_fifo:
 330         if (t->rx_buf != NULL)
 331                 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
 332
 333         if (t->tx_buf != NULL)
 334                 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
 335
 336         mcspi_write_chconf0(spi, chconf);
 337         mcspi->fifo_depth = 0;
 338 }
 339
 340 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 341 {
 342         struct spi_master       *spi_cntrl = mcspi->master;
 343         struct omap2_mcspi_regs *ctx = &mcspi->ctx;
 344         struct omap2_mcspi_cs   *cs;
 345
 346         /* McSPI: context restore */
 347         mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
 348         mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 349
 350         list_for_each_entry(cs, &ctx->cs, node)
 351                 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 352 }
 353
 354 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 355 {
 356         unsigned long timeout;
 357
 358         timeout = jiffies + msecs_to_jiffies(1000);
 359         while (!(readl_relaxed(reg) & bit)) {
 360                 if (time_after(jiffies, timeout)) {
 361                         if (!(readl_relaxed(reg) & bit))
 362                                 return -ETIMEDOUT;
 363                         else
 364                                 return 0;
 365                 }
 366                 cpu_relax();
 367         }
 368         return 0;
 369 }
 370
 371 static void omap2_mcspi_rx_callback(void *data)
 372 {
 373         struct spi_device *spi = data;
 374         struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 375         struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 376
 377         /* We must disable the DMA RX request */
 378         omap2_mcspi_set_dma_req(spi, 1, 0);
 379
 380         complete(&mcspi_dma->dma_rx_completion);
 381 }
 382
 383 static void omap2_mcspi_tx_callback(void *data)
 384 {
 385         struct spi_device *spi = data;
 386         struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
 387         struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 388
 389         /* We must disable the DMA TX request */
 390         omap2_mcspi_set_dma_req(spi, 0, 0);
 391
 392         complete(&mcspi_dma->dma_tx_completion);
 393 }
 394
 395 static void omap2_mcspi_tx_dma(struct spi_device *spi,
 396                                 struct spi_transfer *xfer,
 397                                 struct dma_slave_config cfg)
 398 {
 399         struct omap2_mcspi      *mcspi;
 400         struct omap2_mcspi_dma  *mcspi_dma;
 401         unsigned int            count;
 402
 403         mcspi = spi_master_get_devdata(spi->master);
 404         mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 405         count = xfer->len;
 406
 407         if (mcspi_dma->dma_tx) {
 408                 struct dma_async_tx_descriptor *tx;
 409                 struct scatterlist sg;
 410
 411                 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
 412
 413                 sg_init_table(&sg, 1);
 414                 sg_dma_address(&sg) = xfer->tx_dma;
 415                 sg_dma_len(&sg) = xfer->len;
 416
 417                 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
 418                 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 419                 if (tx) {
 420                         tx->callback = omap2_mcspi_tx_callback;
 421                         tx->callback_param = spi;
 422                         dmaengine_submit(tx);
 423                 } else {
 424                         /* FIXME: fall back to PIO? */
 425                 }
 426         }
 427         dma_async_issue_pending(mcspi_dma->dma_tx);
 428         omap2_mcspi_set_dma_req(spi, 0, 1);
 429
 430 }
 431
 432 static unsigned
 433 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
 434                                 struct dma_slave_config cfg,
 435                                 unsigned es)
 436 {
 437         struct omap2_mcspi      *mcspi;
 438         struct omap2_mcspi_dma  *mcspi_dma;
 439         unsigned int            count, dma_count;
 440         u32                     l;
 441         int                     elements = 0;
 442         int                     word_len, element_count;
 443         struct omap2_mcspi_cs   *cs = spi->controller_state;
 444         mcspi = spi_master_get_devdata(spi->master);
 445         mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 446         count = xfer->len;
 447         dma_count = xfer->len;
 448
 449         if (mcspi->fifo_depth == 0)
 450                 dma_count -= es;
 451
 452         word_len = cs->word_len;
 453         l = mcspi_cached_chconf0(spi);
 454
 455         if (word_len <= 8)
 456                 element_count = count;
 457         else if (word_len <= 16)
 458                 element_count = count >> 1;
 459         else /* word_len <= 32 */
 460                 element_count = count >> 2;
 461
 462         if (mcspi_dma->dma_rx) {
 463                 struct dma_async_tx_descriptor *tx;
 464                 struct scatterlist sg;
 465
 466                 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
 467
 468                 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
 469                         dma_count -= es;
 470
 471                 sg_init_table(&sg, 1);
 472                 sg_dma_address(&sg) = xfer->rx_dma;
 473                 sg_dma_len(&sg) = dma_count;
 474
 475                 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
 476                                 DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
 477                                 DMA_CTRL_ACK);
 478                 if (tx) {
 479                         tx->callback = omap2_mcspi_rx_callback;
 480                         tx->callback_param = spi;
 481                         dmaengine_submit(tx);
 482                 } else {
 483                                 /* FIXME: fall back to PIO? */
 484                 }
 485         }
 486
 487         dma_async_issue_pending(mcspi_dma->dma_rx);
 488         omap2_mcspi_set_dma_req(spi, 1, 1);
 489
 490         wait_for_completion(&mcspi_dma->dma_rx_completion);
 491         dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
 492                          DMA_FROM_DEVICE);
 493
 494         if (mcspi->fifo_depth > 0)
 495                 return count;
 496
 497         omap2_mcspi_set_enable(spi, 0);
 498
 499         elements = element_count - 1;
 500
 501         if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 502                 elements--;
 503
 504                 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 505                                    & OMAP2_MCSPI_CHSTAT_RXS)) {
 506                         u32 w;
 507
 508                         w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 509                         if (word_len <= 8)
 510                                 ((u8 *)xfer->rx_buf)[elements++] = w;
 511                         else if (word_len <= 16)
 512                                 ((u16 *)xfer->rx_buf)[elements++] = w;
 513                         else /* word_len <= 32 */
 514                                 ((u32 *)xfer->rx_buf)[elements++] = w;
 515                 } else {
 516                         int bytes_per_word = mcspi_bytes_per_word(word_len);
 517                         dev_err(&spi->dev, "DMA RX penultimate word empty\n");
 518                         count -= (bytes_per_word << 1);
 519                         omap2_mcspi_set_enable(spi, 1);
 520                         return count;
 521                 }
 522         }
 523         if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 524                                 & OMAP2_MCSPI_CHSTAT_RXS)) {
 525                 u32 w;
 526
 527                 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 528                 if (word_len <= 8)
 529                         ((u8 *)xfer->rx_buf)[elements] = w;
 530                 else if (word_len <= 16)
 531                         ((u16 *)xfer->rx_buf)[elements] = w;
 532                 else /* word_len <= 32 */
 533                         ((u32 *)xfer->rx_buf)[elements] = w;
 534         } else {
 535                 dev_err(&spi->dev, "DMA RX last word empty\n");
 536                 count -= mcspi_bytes_per_word(word_len);
 537         }
 538         omap2_mcspi_set_enable(spi, 1);
 539         return count;
 540 }
 541
 542 static unsigned
 543 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 544 {
 545         struct omap2_mcspi      *mcspi;
 546         struct omap2_mcspi_cs   *cs = spi->controller_state;
 547         struct omap2_mcspi_dma  *mcspi_dma;
 548         unsigned int            count;
 549         u32                     l;
 550         u8                      *rx;
 551         const u8                *tx;
 552         struct dma_slave_config cfg;
 553         enum dma_slave_buswidth width;
 554         unsigned es;
 555         u32                     burst;
 556         void __iomem            *chstat_reg;
 557         void __iomem            *irqstat_reg;
 558         int                     wait_res;
 559
 560         mcspi = spi_master_get_devdata(spi->master);
 561         mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 562         l = mcspi_cached_chconf0(spi);
 563
 564
 565         if (cs->word_len <= 8) {
 566                 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 567                 es = 1;
 568         } else if (cs->word_len <= 16) {
 569                 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 570                 es = 2;
 571         } else {
 572                 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 573                 es = 4;
 574         }
 575
 576         count = xfer->len;
 577         burst = 1;
 578
 579         if (mcspi->fifo_depth > 0) {
 580                 if (count > mcspi->fifo_depth)
 581                         burst = mcspi->fifo_depth / es;
 582                 else
 583                         burst = count / es;
 584         }
 585
 586         memset(&cfg, 0, sizeof(cfg));
 587         cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
 588         cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
 589         cfg.src_addr_width = width;
 590         cfg.dst_addr_width = width;
 591         cfg.src_maxburst = burst;
 592         cfg.dst_maxburst = burst;
 593
 594         rx = xfer->rx_buf;
 595         tx = xfer->tx_buf;
 596
 597         if (tx != NULL)
 598                 omap2_mcspi_tx_dma(spi, xfer, cfg);
 599
 600         if (rx != NULL)
 601                 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
 602
 603         if (tx != NULL) {
 604                 wait_for_completion(&mcspi_dma->dma_tx_completion);
 605                 dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
 606                                  DMA_TO_DEVICE);
 607
 608                 if (mcspi->fifo_depth > 0) {
 609                         irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
 610
 611                         if (mcspi_wait_for_reg_bit(irqstat_reg,
 612                                                 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
 613                                 dev_err(&spi->dev, "EOW timed out\n");
 614
 615                         mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
 616                                         OMAP2_MCSPI_IRQSTATUS_EOW);
 617                 }
 618
 619                 /* for TX_ONLY mode, be sure all words have shifted out */
 620                 if (rx == NULL) {
 621                         chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 622                         if (mcspi->fifo_depth > 0) {
 623                                 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 624                                                 OMAP2_MCSPI_CHSTAT_TXFFE);
 625                                 if (wait_res < 0)
 626                                         dev_err(&spi->dev, "TXFFE timed out\n");
 627                         } else {
 628                                 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
 629                                                 OMAP2_MCSPI_CHSTAT_TXS);
 630                                 if (wait_res < 0)
 631                                         dev_err(&spi->dev, "TXS timed out\n");
 632                         }
 633                         if (wait_res >= 0 &&
 634                                 (mcspi_wait_for_reg_bit(chstat_reg,
 635                                         OMAP2_MCSPI_CHSTAT_EOT) < 0))
 636                                 dev_err(&spi->dev, "EOT timed out\n");
 637                 }
 638         }
 639         return count;
 640 }
 641
 642 static unsigned
 643 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 644 {
 645         struct omap2_mcspi      *mcspi;
 646         struct omap2_mcspi_cs   *cs = spi->controller_state;
 647         unsigned int            count, c;
 648         u32                     l;
 649         void __iomem            *base = cs->base;
 650         void __iomem            *tx_reg;
 651         void __iomem            *rx_reg;
 652         void __iomem            *chstat_reg;
 653         int                     word_len;
 654
 655         mcspi = spi_master_get_devdata(spi->master);
 656         count = xfer->len;
 657         c = count;
 658         word_len = cs->word_len;
 659
 660         l = mcspi_cached_chconf0(spi);
 661
 662         /* We store the pre-calculated register addresses on stack to speed
 663          * up the transfer loop. */
 664         tx_reg          = base + OMAP2_MCSPI_TX0;
 665         rx_reg          = base + OMAP2_MCSPI_RX0;
 666         chstat_reg      = base + OMAP2_MCSPI_CHSTAT0;
 667
 668         if (c < (word_len>>3))
 669                 return 0;
 670
 671         if (word_len <= 8) {
 672                 u8              *rx;
 673                 const u8        *tx;
 674
 675                 rx = xfer->rx_buf;
 676                 tx = xfer->tx_buf;
 677
 678                 do {
 679                         c -= 1;
 680                         if (tx != NULL) {
 681                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 682                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 683                                         dev_err(&spi->dev, "TXS timed out\n");
 684                                         goto out;
 685                                 }
 686                                 dev_vdbg(&spi->dev, "write-%d %02x\n",
 687                                                 word_len, *tx);
 688                                 writel_relaxed(*tx++, tx_reg);
 689                         }
 690                         if (rx != NULL) {
 691                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 692                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 693                                         dev_err(&spi->dev, "RXS timed out\n");
 694                                         goto out;
 695                                 }
 696
 697                                 if (c == 1 && tx == NULL &&
 698                                     (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 699                                         omap2_mcspi_set_enable(spi, 0);
 700                                         *rx++ = readl_relaxed(rx_reg);
 701                                         dev_vdbg(&spi->dev, "read-%d %02x\n",
 702                                                     word_len, *(rx - 1));
 703                                         if (mcspi_wait_for_reg_bit(chstat_reg,
 704                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 705                                                 dev_err(&spi->dev,
 706                                                         "RXS timed out\n");
 707                                                 goto out;
 708                                         }
 709                                         c = 0;
 710                                 } else if (c == 0 && tx == NULL) {
 711                                         omap2_mcspi_set_enable(spi, 0);
 712                                 }
 713
 714                                 *rx++ = readl_relaxed(rx_reg);
 715                                 dev_vdbg(&spi->dev, "read-%d %02x\n",
 716                                                 word_len, *(rx - 1));
 717                         }
 718                 } while (c);
 719         } else if (word_len <= 16) {
 720                 u16             *rx;
 721                 const u16       *tx;
 722
 723                 rx = xfer->rx_buf;
 724                 tx = xfer->tx_buf;
 725                 do {
 726                         c -= 2;
 727                         if (tx != NULL) {
 728                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 729                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 730                                         dev_err(&spi->dev, "TXS timed out\n");
 731                                         goto out;
 732                                 }
 733                                 dev_vdbg(&spi->dev, "write-%d %04x\n",
 734                                                 word_len, *tx);
 735                                 writel_relaxed(*tx++, tx_reg);
 736                         }
 737                         if (rx != NULL) {
 738                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 739                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 740                                         dev_err(&spi->dev, "RXS timed out\n");
 741                                         goto out;
 742                                 }
 743
 744                                 if (c == 2 && tx == NULL &&
 745                                     (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 746                                         omap2_mcspi_set_enable(spi, 0);
 747                                         *rx++ = readl_relaxed(rx_reg);
 748                                         dev_vdbg(&spi->dev, "read-%d %04x\n",
 749                                                     word_len, *(rx - 1));
 750                                         if (mcspi_wait_for_reg_bit(chstat_reg,
 751                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 752                                                 dev_err(&spi->dev,
 753                                                         "RXS timed out\n");
 754                                                 goto out;
 755                                         }
 756                                         c = 0;
 757                                 } else if (c == 0 && tx == NULL) {
 758                                         omap2_mcspi_set_enable(spi, 0);
 759                                 }
 760
 761                                 *rx++ = readl_relaxed(rx_reg);
 762                                 dev_vdbg(&spi->dev, "read-%d %04x\n",
 763                                                 word_len, *(rx - 1));
 764                         }
 765                 } while (c >= 2);
 766         } else if (word_len <= 32) {
 767                 u32             *rx;
 768                 const u32       *tx;
 769
 770                 rx = xfer->rx_buf;
 771                 tx = xfer->tx_buf;
 772                 do {
 773                         c -= 4;
 774                         if (tx != NULL) {
 775                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 776                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 777                                         dev_err(&spi->dev, "TXS timed out\n");
 778                                         goto out;
 779                                 }
 780                                 dev_vdbg(&spi->dev, "write-%d %08x\n",
 781                                                 word_len, *tx);
 782                                 writel_relaxed(*tx++, tx_reg);
 783                         }
 784                         if (rx != NULL) {
 785                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 786                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 787                                         dev_err(&spi->dev, "RXS timed out\n");
 788                                         goto out;
 789                                 }
 790
 791                                 if (c == 4 && tx == NULL &&
 792                                     (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 793                                         omap2_mcspi_set_enable(spi, 0);
 794                                         *rx++ = readl_relaxed(rx_reg);
 795                                         dev_vdbg(&spi->dev, "read-%d %08x\n",
 796                                                     word_len, *(rx - 1));
 797                                         if (mcspi_wait_for_reg_bit(chstat_reg,
 798                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 799                                                 dev_err(&spi->dev,
 800                                                         "RXS timed out\n");
 801                                                 goto out;
 802                                         }
 803                                         c = 0;
 804                                 } else if (c == 0 && tx == NULL) {
 805                                         omap2_mcspi_set_enable(spi, 0);
 806                                 }
 807
 808                                 *rx++ = readl_relaxed(rx_reg);
 809                                 dev_vdbg(&spi->dev, "read-%d %08x\n",
 810                                                 word_len, *(rx - 1));
 811                         }
 812                 } while (c >= 4);
 813         }
 814
 815         /* for TX_ONLY mode, be sure all words have shifted out */
 816         if (xfer->rx_buf == NULL) {
 817                 if (mcspi_wait_for_reg_bit(chstat_reg,
 818                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 819                         dev_err(&spi->dev, "TXS timed out\n");
 820                 } else if (mcspi_wait_for_reg_bit(chstat_reg,
 821                                 OMAP2_MCSPI_CHSTAT_EOT) < 0)
 822                         dev_err(&spi->dev, "EOT timed out\n");
 823
 824                 /* disable chan to purge rx datas received in TX_ONLY transfer,
 825                  * otherwise these rx datas will affect the direct following
 826                  * RX_ONLY transfer.
 827                  */
 828                 omap2_mcspi_set_enable(spi, 0);
 829         }
 830 out:
 831         omap2_mcspi_set_enable(spi, 1);
 832         return count - c;
 833 }
 834
 835 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 836 {
 837         u32 div;
 838
 839         for (div = 0; div < 15; div++)
 840                 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 841                         return div;
 842
 843         return 15;
 844 }
 845
 846 /* called only when no transfer is active to this device */
 847 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 848                 struct spi_transfer *t)
 849 {
 850         struct omap2_mcspi_cs *cs = spi->controller_state;
 851         struct omap2_mcspi *mcspi;
 852         struct spi_master *spi_cntrl;
 853         u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
 854         u8 word_len = spi->bits_per_word;
 855         u32 speed_hz = spi->max_speed_hz;
 856
 857         mcspi = spi_master_get_devdata(spi->master);
 858         spi_cntrl = mcspi->master;
 859
 860         if (t != NULL && t->bits_per_word)
 861                 word_len = t->bits_per_word;
 862
 863         cs->word_len = word_len;
 864
 865         if (t && t->speed_hz)
 866                 speed_hz = t->speed_hz;
 867
 868         speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 869         if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
 870                 clkd = omap2_mcspi_calc_divisor(speed_hz);
 871                 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
 872                 clkg = 0;
 873         } else {
 874                 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
 875                 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
 876                 clkd = (div - 1) & 0xf;
 877                 extclk = (div - 1) >> 4;
 878                 clkg = OMAP2_MCSPI_CHCONF_CLKG;
 879         }
 880
 881         l = mcspi_cached_chconf0(spi);
 882
 883         /* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 884          * REVISIT: this controller could support SPI_3WIRE mode.
 885          */
 886         if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
 887                 l &= ~OMAP2_MCSPI_CHCONF_IS;
 888                 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
 889                 l |= OMAP2_MCSPI_CHCONF_DPE0;
 890         } else {
 891                 l |= OMAP2_MCSPI_CHCONF_IS;
 892                 l |= OMAP2_MCSPI_CHCONF_DPE1;
 893                 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
 894         }
 895
 896         /* wordlength */
 897         l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 898         l |= (word_len - 1) << 7;
 899
 900         /* set chipselect polarity; manage with FORCE */
 901         if (!(spi->mode & SPI_CS_HIGH))
 902                 l |= OMAP2_MCSPI_CHCONF_EPOL;   /* active-low; normal */
 903         else
 904                 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 905
 906         /* set clock divisor */
 907         l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 908         l |= clkd << 2;
 909
 910         /* set clock granularity */
 911         l &= ~OMAP2_MCSPI_CHCONF_CLKG;
 912         l |= clkg;
 913         if (clkg) {
 914                 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
 915                 cs->chctrl0 |= extclk << 8;
 916                 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
 917         }
 918
 919         /* set SPI mode 0..3 */
 920         if (spi->mode & SPI_CPOL)
 921                 l |= OMAP2_MCSPI_CHCONF_POL;
 922         else
 923                 l &= ~OMAP2_MCSPI_CHCONF_POL;
 924         if (spi->mode & SPI_CPHA)
 925                 l |= OMAP2_MCSPI_CHCONF_PHA;
 926         else
 927                 l &= ~OMAP2_MCSPI_CHCONF_PHA;
 928
 929         mcspi_write_chconf0(spi, l);
 930
 931         cs->mode = spi->mode;
 932
 933         dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 934                         speed_hz,
 935                         (spi->mode & SPI_CPHA) ? "trailing" : "leading",
 936                         (spi->mode & SPI_CPOL) ? "inverted" : "normal");
 937
 938         return 0;
 939 }
 940
 941 /*
 942  * Note that we currently allow DMA only if we get a channel
 943  * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
 944  */
 945 static int omap2_mcspi_request_dma(struct spi_device *spi)
 946 {
 947         struct spi_master       *master = spi->master;
 948         struct omap2_mcspi      *mcspi;
 949         struct omap2_mcspi_dma  *mcspi_dma;
 950         dma_cap_mask_t mask;
 951         unsigned sig;
 952
 953         mcspi = spi_master_get_devdata(master);
 954         mcspi_dma = mcspi->dma_channels + spi->chip_select;
 955
 956         init_completion(&mcspi_dma->dma_rx_completion);
 957         init_completion(&mcspi_dma->dma_tx_completion);
 958
 959         dma_cap_zero(mask);
 960         dma_cap_set(DMA_SLAVE, mask);
 961         sig = mcspi_dma->dma_rx_sync_dev;
 962
 963         mcspi_dma->dma_rx =
 964                 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 965                                                  &sig, &master->dev,
 966                                                  mcspi_dma->dma_rx_ch_name);
 967         if (!mcspi_dma->dma_rx)
 968                 goto no_dma;
 969
 970         sig = mcspi_dma->dma_tx_sync_dev;
 971         mcspi_dma->dma_tx =
 972                 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
 973                                                  &sig, &master->dev,
 974                                                  mcspi_dma->dma_tx_ch_name);
 975
 976         if (!mcspi_dma->dma_tx) {
 977                 dma_release_channel(mcspi_dma->dma_rx);
 978                 mcspi_dma->dma_rx = NULL;
 979                 goto no_dma;
 980         }
 981
 982         return 0;
 983
 984 no_dma:
 985         dev_warn(&spi->dev, "not using DMA for McSPI\n");
 986         return -EAGAIN;
 987 }
 988
 989 static int omap2_mcspi_setup(struct spi_device *spi)
 990 {
 991         int                     ret;
 992         struct omap2_mcspi      *mcspi = spi_master_get_devdata(spi->master);
 993         struct omap2_mcspi_regs *ctx = &mcspi->ctx;
 994         struct omap2_mcspi_dma  *mcspi_dma;
 995         struct omap2_mcspi_cs   *cs = spi->controller_state;
 996
 997         mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 998
 999         if (!cs) {
1000                 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1001                 if (!cs)
1002                         return -ENOMEM;
1003                 cs->base = mcspi->base + spi->chip_select * 0x14;
1004                 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1005                 cs->mode = 0;
1006                 cs->chconf0 = 0;
1007                 cs->chctrl0 = 0;
1008                 spi->controller_state = cs;
1009                 /* Link this to context save list */
1010                 list_add_tail(&cs->node, &ctx->cs);
1011         }
1012
1013         if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1014                 ret = omap2_mcspi_request_dma(spi);
1015                 if (ret < 0 && ret != -EAGAIN)
1016                         return ret;
1017         }
1018
1019         ret = pm_runtime_get_sync(mcspi->dev);
1020         if (ret < 0)
1021                 return ret;
1022
1023         ret = omap2_mcspi_setup_transfer(spi, NULL);
1024         pm_runtime_mark_last_busy(mcspi->dev);
1025         pm_runtime_put_autosuspend(mcspi->dev);
1026
1027         return ret;
1028 }
1029
1030 static void omap2_mcspi_cleanup(struct spi_device *spi)
1031 {
1032         struct omap2_mcspi      *mcspi;
1033         struct omap2_mcspi_dma  *mcspi_dma;
1034         struct omap2_mcspi_cs   *cs;
1035
1036         mcspi = spi_master_get_devdata(spi->master);
1037
1038         if (spi->controller_state) {
1039                 /* Unlink controller state from context save list */
1040                 cs = spi->controller_state;
1041                 list_del(&cs->node);
1042
1043                 kfree(cs);
1044         }
1045
1046         if (spi->chip_select < spi->master->num_chipselect) {
1047                 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1048
1049                 if (mcspi_dma->dma_rx) {
1050                         dma_release_channel(mcspi_dma->dma_rx);
1051                         mcspi_dma->dma_rx = NULL;
1052                 }
1053                 if (mcspi_dma->dma_tx) {
1054                         dma_release_channel(mcspi_dma->dma_tx);
1055                         mcspi_dma->dma_tx = NULL;
1056                 }
1057         }
1058 }
1059
1060 static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
1061 {
1062
1063         /* We only enable one channel at a time -- the one whose message is
1064          * -- although this controller would gladly
1065          * arbitrate among multiple channels.  This corresponds to "single
1066          * channel" master mode.  As a side effect, we need to manage the
1067          * chipselect with the FORCE bit ... CS != channel enable.
1068          */
1069
1070         struct spi_device               *spi;
1071         struct spi_transfer             *t = NULL;
1072         struct spi_master               *master;
1073         struct omap2_mcspi_dma          *mcspi_dma;
1074         int                             cs_active = 0;
1075         struct omap2_mcspi_cs           *cs;
1076         struct omap2_mcspi_device_config *cd;
1077         int                             par_override = 0;
1078         int                             status = 0;
1079         u32                             chconf;
1080
1081         spi = m->spi;
1082         master = spi->master;
1083         mcspi_dma = mcspi->dma_channels + spi->chip_select;
1084         cs = spi->controller_state;
1085         cd = spi->controller_data;
1086
1087         /*
1088          * The slave driver could have changed spi->mode in which case
1089          * it will be different from cs->mode (the current hardware setup).
1090          * If so, set par_override (even though its not a parity issue) so
1091          * omap2_mcspi_setup_transfer will be called to configure the hardware
1092          * with the correct mode on the first iteration of the loop below.
1093          */
1094         if (spi->mode != cs->mode)
1095                 par_override = 1;
1096
1097         omap2_mcspi_set_enable(spi, 0);
1098         list_for_each_entry(t, &m->transfers, transfer_list) {
1099                 if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
1100                         status = -EINVAL;
1101                         break;
1102                 }
1103                 if (par_override ||
1104                     (t->speed_hz != spi->max_speed_hz) ||
1105                     (t->bits_per_word != spi->bits_per_word)) {
1106                         par_override = 1;
1107                         status = omap2_mcspi_setup_transfer(spi, t);
1108                         if (status < 0)
1109                                 break;
1110                         if (t->speed_hz == spi->max_speed_hz &&
1111                             t->bits_per_word == spi->bits_per_word)
1112                                 par_override = 0;
1113                 }
1114                 if (cd && cd->cs_per_word) {
1115                         chconf = mcspi->ctx.modulctrl;
1116                         chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1117                         mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1118                         mcspi->ctx.modulctrl =
1119                                 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1120                 }
1121
1122
1123                 if (!cs_active) {
1124                         omap2_mcspi_force_cs(spi, 1);
1125                         cs_active = 1;
1126                 }
1127
1128                 chconf = mcspi_cached_chconf0(spi);
1129                 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1130                 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1131
1132                 if (t->tx_buf == NULL)
1133                         chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1134                 else if (t->rx_buf == NULL)
1135                         chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1136
1137                 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1138                         /* Turbo mode is for more than one word */
1139                         if (t->len > ((cs->word_len + 7) >> 3))
1140                                 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1141                 }
1142
1143                 mcspi_write_chconf0(spi, chconf);
1144
1145                 if (t->len) {
1146                         unsigned        count;
1147
1148                         if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1149                             (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1150                                 omap2_mcspi_set_fifo(spi, t, 1);
1151
1152                         omap2_mcspi_set_enable(spi, 1);
1153
1154                         /* RX_ONLY mode needs dummy data in TX reg */
1155                         if (t->tx_buf == NULL)
1156                                 writel_relaxed(0, cs->base
1157                                                 + OMAP2_MCSPI_TX0);
1158
1159                         if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1160                             (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
1161                                 count = omap2_mcspi_txrx_dma(spi, t);
1162                         else
1163                                 count = omap2_mcspi_txrx_pio(spi, t);
1164                         m->actual_length += count;
1165
1166                         if (count != t->len) {
1167                                 status = -EIO;
1168                                 break;
1169                         }
1170                 }
1171
1172                 if (t->delay_usecs)
1173                         udelay(t->delay_usecs);
1174
1175                 /* ignore the "leave it on after last xfer" hint */
1176                 if (t->cs_change) {
1177                         omap2_mcspi_force_cs(spi, 0);
1178                         cs_active = 0;
1179                 }
1180
1181                 omap2_mcspi_set_enable(spi, 0);
1182
1183                 if (mcspi->fifo_depth > 0)
1184                         omap2_mcspi_set_fifo(spi, t, 0);
1185         }
1186         /* Restore defaults if they were overriden */
1187         if (par_override) {
1188                 par_override = 0;
1189                 status = omap2_mcspi_setup_transfer(spi, NULL);
1190         }
1191
1192         if (cs_active)
1193                 omap2_mcspi_force_cs(spi, 0);
1194
1195         if (cd && cd->cs_per_word) {
1196                 chconf = mcspi->ctx.modulctrl;
1197                 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1198                 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1199                 mcspi->ctx.modulctrl =
1200                         mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1201         }
1202
1203         omap2_mcspi_set_enable(spi, 0);
1204
1205         if (mcspi->fifo_depth > 0 && t)
1206                 omap2_mcspi_set_fifo(spi, t, 0);
1207
1208         m->status = status;
1209 }
1210
1211 static int omap2_mcspi_transfer_one_message(struct spi_master *master,
1212                 struct spi_message *m)
1213 {
1214         struct spi_device       *spi;
1215         struct omap2_mcspi      *mcspi;
1216         struct omap2_mcspi_dma  *mcspi_dma;
1217         struct spi_transfer     *t;
1218
1219         spi = m->spi;
1220         mcspi = spi_master_get_devdata(master);
1221         mcspi_dma = mcspi->dma_channels + spi->chip_select;
1222         m->actual_length = 0;
1223         m->status = 0;
1224
1225         list_for_each_entry(t, &m->transfers, transfer_list) {
1226                 const void      *tx_buf = t->tx_buf;
1227                 void            *rx_buf = t->rx_buf;
1228                 unsigned        len = t->len;
1229
1230                 if ((len && !(rx_buf || tx_buf))) {
1231                         dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1232                                         t->speed_hz,
1233                                         len,
1234                                         tx_buf ? "tx" : "",
1235                                         rx_buf ? "rx" : "",
1236                                         t->bits_per_word);
1237                         return -EINVAL;
1238                 }
1239
1240                 if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1241                         continue;
1242
1243                 if (mcspi_dma->dma_tx && tx_buf != NULL) {
1244                         t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1245                                         len, DMA_TO_DEVICE);
1246                         if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1247                                 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1248                                                 'T', len);
1249                                 return -EINVAL;
1250                         }
1251                 }
1252                 if (mcspi_dma->dma_rx && rx_buf != NULL) {
1253                         t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1254                                         DMA_FROM_DEVICE);
1255                         if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1256                                 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1257                                                 'R', len);
1258                                 if (tx_buf != NULL)
1259                                         dma_unmap_single(mcspi->dev, t->tx_dma,
1260                                                         len, DMA_TO_DEVICE);
1261                                 return -EINVAL;
1262                         }
1263                 }
1264         }
1265
1266         omap2_mcspi_work(mcspi, m);
1267         spi_finalize_current_message(master);
1268         return 0;
1269 }
1270
1271 static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1272 {
1273         struct spi_master       *master = mcspi->master;
1274         struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1275         int                     ret = 0;
1276
1277         ret = pm_runtime_get_sync(mcspi->dev);
1278         if (ret < 0)
1279                 return ret;
1280
1281         mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1282                         OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1283         ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1284
1285         omap2_mcspi_set_master_mode(master);
1286         pm_runtime_mark_last_busy(mcspi->dev);
1287         pm_runtime_put_autosuspend(mcspi->dev);
1288         return 0;
1289 }
1290
1291 static int omap_mcspi_runtime_resume(struct device *dev)
1292 {
1293         struct omap2_mcspi      *mcspi;
1294         struct spi_master       *master;
1295
1296         master = dev_get_drvdata(dev);
1297         mcspi = spi_master_get_devdata(master);
1298         omap2_mcspi_restore_ctx(mcspi);
1299
1300         return 0;
1301 }
1302
1303 static struct omap2_mcspi_platform_config omap2_pdata = {
1304         .regs_offset = 0,
1305 };
1306
1307 static struct omap2_mcspi_platform_config omap4_pdata = {
1308         .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1309 };
1310
1311 static const struct of_device_id omap_mcspi_of_match[] = {
1312         {
1313                 .compatible = "ti,omap2-mcspi",
1314                 .data = &omap2_pdata,
1315         },
1316         {
1317                 .compatible = "ti,omap4-mcspi",
1318                 .data = &omap4_pdata,
1319         },
1320         { },
1321 };
1322 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1323
1324 static int omap2_mcspi_probe(struct platform_device *pdev)
1325 {
1326         struct spi_master       *master;
1327         const struct omap2_mcspi_platform_config *pdata;
1328         struct omap2_mcspi      *mcspi;
1329         struct resource         *r;
1330         int                     status = 0, i;
1331         u32                     regs_offset = 0;
1332         static int              bus_num = 1;
1333         struct device_node      *node = pdev->dev.of_node;
1334         const struct of_device_id *match;
1335
1336         master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1337         if (master == NULL) {
1338                 dev_dbg(&pdev->dev, "master allocation failed\n");
1339                 return -ENOMEM;
1340         }
1341
1342         /* the spi->mode bits understood by this driver: */
1343         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1344         master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1345         master->setup = omap2_mcspi_setup;
1346         master->auto_runtime_pm = true;
1347         master->transfer_one_message = omap2_mcspi_transfer_one_message;
1348         master->cleanup = omap2_mcspi_cleanup;
1349         master->dev.of_node = node;
1350         master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1351         master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1352
1353         platform_set_drvdata(pdev, master);
1354
1355         mcspi = spi_master_get_devdata(master);
1356         mcspi->master = master;
1357
1358         match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1359         if (match) {
1360                 u32 num_cs = 1; /* default number of chipselect */
1361                 pdata = match->data;
1362
1363                 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1364                 master->num_chipselect = num_cs;
1365                 master->bus_num = bus_num++;
1366                 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1367                         mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1368         } else {
1369                 pdata = dev_get_platdata(&pdev->dev);
1370                 master->num_chipselect = pdata->num_cs;
1371                 if (pdev->id != -1)
1372                         master->bus_num = pdev->id;
1373                 mcspi->pin_dir = pdata->pin_dir;
1374         }
1375         regs_offset = pdata->regs_offset;
1376
1377         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1378         if (r == NULL) {
1379                 status = -ENODEV;
1380                 goto free_master;
1381         }
1382
1383         r->start += regs_offset;
1384         r->end += regs_offset;
1385         mcspi->phys = r->start;
1386
1387         mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1388         if (IS_ERR(mcspi->base)) {
1389                 status = PTR_ERR(mcspi->base);
1390                 goto free_master;
1391         }
1392
1393         mcspi->dev = &pdev->dev;
1394
1395         INIT_LIST_HEAD(&mcspi->ctx.cs);
1396
1397         mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1398                                            sizeof(struct omap2_mcspi_dma),
1399                                            GFP_KERNEL);
1400         if (mcspi->dma_channels == NULL) {
1401                 status = -ENOMEM;
1402                 goto free_master;
1403         }
1404
1405         for (i = 0; i < master->num_chipselect; i++) {
1406                 char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1407                 char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1408                 struct resource *dma_res;
1409
1410                 sprintf(dma_rx_ch_name, "rx%d", i);
1411                 if (!pdev->dev.of_node) {
1412                         dma_res =
1413                                 platform_get_resource_byname(pdev,
1414                                                              IORESOURCE_DMA,
1415                                                              dma_rx_ch_name);
1416                         if (!dma_res) {
1417                                 dev_dbg(&pdev->dev,
1418                                         "cannot get DMA RX channel\n");
1419                                 status = -ENODEV;
1420                                 break;
1421                         }
1422
1423                         mcspi->dma_channels[i].dma_rx_sync_dev =
1424                                 dma_res->start;
1425                 }
1426                 sprintf(dma_tx_ch_name, "tx%d", i);
1427                 if (!pdev->dev.of_node) {
1428                         dma_res =
1429                                 platform_get_resource_byname(pdev,
1430                                                              IORESOURCE_DMA,
1431                                                              dma_tx_ch_name);
1432                         if (!dma_res) {
1433                                 dev_dbg(&pdev->dev,
1434                                         "cannot get DMA TX channel\n");
1435                                 status = -ENODEV;
1436                                 break;
1437                         }
1438
1439                         mcspi->dma_channels[i].dma_tx_sync_dev =
1440                                 dma_res->start;
1441                 }
1442         }
1443
1444         if (status < 0)
1445                 goto free_master;
1446
1447         pm_runtime_use_autosuspend(&pdev->dev);
1448         pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1449         pm_runtime_enable(&pdev->dev);
1450
1451         status = omap2_mcspi_master_setup(mcspi);
1452         if (status < 0)
1453                 goto disable_pm;
1454
1455         status = devm_spi_register_master(&pdev->dev, master);
1456         if (status < 0)
1457                 goto disable_pm;
1458
1459         return status;
1460
1461 disable_pm:
1462         pm_runtime_disable(&pdev->dev);
1463 free_master:
1464         spi_master_put(master);
1465         return status;
1466 }
1467
1468 static int omap2_mcspi_remove(struct platform_device *pdev)
1469 {
1470         struct spi_master *master = platform_get_drvdata(pdev);
1471         struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1472
1473         pm_runtime_put_sync(mcspi->dev);
1474         pm_runtime_disable(&pdev->dev);
1475
1476         return 0;
1477 }
1478
1479 /* work with hotplug and coldplug */
1480 MODULE_ALIAS("platform:omap2_mcspi");
1481
1482 #ifdef  CONFIG_SUSPEND
1483 /*
1484  * When SPI wake up from off-mode, CS is in activate state. If it was in
1485  * unactive state when driver was suspend, then force it to unactive state at
1486  * wake up.
1487  */
1488 static int omap2_mcspi_resume(struct device *dev)
1489 {
1490         struct spi_master       *master = dev_get_drvdata(dev);
1491         struct omap2_mcspi      *mcspi = spi_master_get_devdata(master);
1492         struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1493         struct omap2_mcspi_cs   *cs;
1494
1495         pm_runtime_get_sync(mcspi->dev);
1496         list_for_each_entry(cs, &ctx->cs, node) {
1497                 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1498                         /*
1499                          * We need to toggle CS state for OMAP take this
1500                          * change in account.
1501                          */
1502                         cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1503                         writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1504                         cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1505                         writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1506                 }
1507         }
1508         pm_runtime_mark_last_busy(mcspi->dev);
1509         pm_runtime_put_autosuspend(mcspi->dev);
1510         return 0;
1511 }
1512 #else
1513 #define omap2_mcspi_resume      NULL
1514 #endif
1515
1516 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1517         .resume = omap2_mcspi_resume,
1518         .runtime_resume = omap_mcspi_runtime_resume,
1519 };
1520
1521 static struct platform_driver omap2_mcspi_driver = {
1522         .driver = {
1523                 .name =         "omap2_mcspi",
1524                 .owner =        THIS_MODULE,
1525                 .pm =           &omap2_mcspi_pm_ops,
1526                 .of_match_table = omap_mcspi_of_match,
1527         },
1528         .probe =        omap2_mcspi_probe,
1529         .remove =       omap2_mcspi_remove,
1530 };
1531
1532 module_platform_driver(omap2_mcspi_driver);
1533 MODULE_LICENSE("GPL");