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/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/module.h>
  28 #include <linux/device.h>
  29 #include <linux/delay.h>
  30 #include <linux/dma-mapping.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/err.h>
  33 #include <linux/clk.h>
  34 #include <linux/io.h>
  35 #include <linux/slab.h>
  36 #include <linux/pm_runtime.h>
  37 #include <linux/of.h>
  38 #include <linux/of_device.h>
  39
  40 #include <linux/spi/spi.h>
  41
  42 #include <plat/dma.h>
  43 #include <plat/clock.h>
  44 #include <plat/mcspi.h>
  45
  46 #define OMAP2_MCSPI_MAX_FREQ            48000000
  47
  48 /* OMAP2 has 3 SPI controllers, while OMAP3 has 4 */
  49 #define OMAP2_MCSPI_MAX_CTRL            4
  50
  51 #define OMAP2_MCSPI_REVISION            0x00
  52 #define OMAP2_MCSPI_SYSSTATUS           0x14
  53 #define OMAP2_MCSPI_IRQSTATUS           0x18
  54 #define OMAP2_MCSPI_IRQENABLE           0x1c
  55 #define OMAP2_MCSPI_WAKEUPENABLE        0x20
  56 #define OMAP2_MCSPI_SYST                0x24
  57 #define OMAP2_MCSPI_MODULCTRL           0x28
  58
  59 /* per-channel banks, 0x14 bytes each, first is: */
  60 #define OMAP2_MCSPI_CHCONF0             0x2c
  61 #define OMAP2_MCSPI_CHSTAT0             0x30
  62 #define OMAP2_MCSPI_CHCTRL0             0x34
  63 #define OMAP2_MCSPI_TX0                 0x38
  64 #define OMAP2_MCSPI_RX0                 0x3c
  65
  66 /* per-register bitmasks: */
  67
  68 #define OMAP2_MCSPI_MODULCTRL_SINGLE    BIT(0)
  69 #define OMAP2_MCSPI_MODULCTRL_MS        BIT(2)
  70 #define OMAP2_MCSPI_MODULCTRL_STEST     BIT(3)
  71
  72 #define OMAP2_MCSPI_CHCONF_PHA          BIT(0)
  73 #define OMAP2_MCSPI_CHCONF_POL          BIT(1)
  74 #define OMAP2_MCSPI_CHCONF_CLKD_MASK    (0x0f << 2)
  75 #define OMAP2_MCSPI_CHCONF_EPOL         BIT(6)
  76 #define OMAP2_MCSPI_CHCONF_WL_MASK      (0x1f << 7)
  77 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY  BIT(12)
  78 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY  BIT(13)
  79 #define OMAP2_MCSPI_CHCONF_TRM_MASK     (0x03 << 12)
  80 #define OMAP2_MCSPI_CHCONF_DMAW         BIT(14)
  81 #define OMAP2_MCSPI_CHCONF_DMAR         BIT(15)
  82 #define OMAP2_MCSPI_CHCONF_DPE0         BIT(16)
  83 #define OMAP2_MCSPI_CHCONF_DPE1         BIT(17)
  84 #define OMAP2_MCSPI_CHCONF_IS           BIT(18)
  85 #define OMAP2_MCSPI_CHCONF_TURBO        BIT(19)
  86 #define OMAP2_MCSPI_CHCONF_FORCE        BIT(20)
  87
  88 #define OMAP2_MCSPI_CHSTAT_RXS          BIT(0)
  89 #define OMAP2_MCSPI_CHSTAT_TXS          BIT(1)
  90 #define OMAP2_MCSPI_CHSTAT_EOT          BIT(2)
  91
  92 #define OMAP2_MCSPI_CHCTRL_EN           BIT(0)
  93
  94 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN   BIT(0)
  95
  96 /* We have 2 DMA channels per CS, one for RX and one for TX */
  97 struct omap2_mcspi_dma {
  98         int dma_tx_channel;
  99         int dma_rx_channel;
 100
 101         int dma_tx_sync_dev;
 102         int dma_rx_sync_dev;
 103
 104         struct completion dma_tx_completion;
 105         struct completion dma_rx_completion;
 106 };
 107
 108 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 109  * cache operations; better heuristics consider wordsize and bitrate.
 110  */
 111 #define DMA_MIN_BYTES                   160
 112
 113
 114 struct omap2_mcspi {
 115         struct work_struct      work;
 116         /* lock protects queue and registers */
 117         spinlock_t              lock;
 118         struct list_head        msg_queue;
 119         struct spi_master       *master;
 120         /* Virtual base address of the controller */
 121         void __iomem            *base;
 122         unsigned long           phys;
 123         /* SPI1 has 4 channels, while SPI2 has 2 */
 124         struct omap2_mcspi_dma  *dma_channels;
 125         struct  device          *dev;
 126         struct workqueue_struct *wq;
 127 };
 128
 129 struct omap2_mcspi_cs {
 130         void __iomem            *base;
 131         unsigned long           phys;
 132         int                     word_len;
 133         struct list_head        node;
 134         /* Context save and restore shadow register */
 135         u32                     chconf0;
 136 };
 137
 138 /* used for context save and restore, structure members to be updated whenever
 139  * corresponding registers are modified.
 140  */
 141 struct omap2_mcspi_regs {
 142         u32 modulctrl;
 143         u32 wakeupenable;
 144         struct list_head cs;
 145 };
 146
 147 static struct omap2_mcspi_regs omap2_mcspi_ctx[OMAP2_MCSPI_MAX_CTRL];
 148
 149 #define MOD_REG_BIT(val, mask, set) do { \
 150         if (set) \
 151                 val |= mask; \
 152         else \
 153                 val &= ~mask; \
 154 } while (0)
 155
 156 static inline void mcspi_write_reg(struct spi_master *master,
 157                 int idx, u32 val)
 158 {
 159         struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 160
 161         __raw_writel(val, mcspi->base + idx);
 162 }
 163
 164 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
 165 {
 166         struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
 167
 168         return __raw_readl(mcspi->base + idx);
 169 }
 170
 171 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
 172                 int idx, u32 val)
 173 {
 174         struct omap2_mcspi_cs   *cs = spi->controller_state;
 175
 176         __raw_writel(val, cs->base +  idx);
 177 }
 178
 179 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
 180 {
 181         struct omap2_mcspi_cs   *cs = spi->controller_state;
 182
 183         return __raw_readl(cs->base + idx);
 184 }
 185
 186 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
 187 {
 188         struct omap2_mcspi_cs *cs = spi->controller_state;
 189
 190         return cs->chconf0;
 191 }
 192
 193 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
 194 {
 195         struct omap2_mcspi_cs *cs = spi->controller_state;
 196
 197         cs->chconf0 = val;
 198         mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
 199         mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 200 }
 201
 202 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
 203                 int is_read, int enable)
 204 {
 205         u32 l, rw;
 206
 207         l = mcspi_cached_chconf0(spi);
 208
 209         if (is_read) /* 1 is read, 0 write */
 210                 rw = OMAP2_MCSPI_CHCONF_DMAR;
 211         else
 212                 rw = OMAP2_MCSPI_CHCONF_DMAW;
 213
 214         MOD_REG_BIT(l, rw, enable);
 215         mcspi_write_chconf0(spi, l);
 216 }
 217
 218 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
 219 {
 220         u32 l;
 221
 222         l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
 223         mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
 224         /* Flash post-writes */
 225         mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
 226 }
 227
 228 static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 229 {
 230         u32 l;
 231
 232         l = mcspi_cached_chconf0(spi);
 233         MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active);
 234         mcspi_write_chconf0(spi, l);
 235 }
 236
 237 static void omap2_mcspi_set_master_mode(struct spi_master *master)
 238 {
 239         u32 l;
 240
 241         /* setup when switching from (reset default) slave mode
 242          * to single-channel master mode
 243          */
 244         l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
 245         MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_STEST, 0);
 246         MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0);
 247         MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
 248         mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 249
 250         omap2_mcspi_ctx[master->bus_num - 1].modulctrl = l;
 251 }
 252
 253 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 254 {
 255         struct spi_master *spi_cntrl;
 256         struct omap2_mcspi_cs *cs;
 257         spi_cntrl = mcspi->master;
 258
 259         /* McSPI: context restore */
 260         mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL,
 261                         omap2_mcspi_ctx[spi_cntrl->bus_num - 1].modulctrl);
 262
 263         mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE,
 264                         omap2_mcspi_ctx[spi_cntrl->bus_num - 1].wakeupenable);
 265
 266         list_for_each_entry(cs, &omap2_mcspi_ctx[spi_cntrl->bus_num - 1].cs,
 267                         node)
 268                 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 269 }
 270 static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
 271 {
 272         pm_runtime_put_sync(mcspi->dev);
 273 }
 274
 275 static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi)
 276 {
 277         return pm_runtime_get_sync(mcspi->dev);
 278 }
 279
 280 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
 281 {
 282         unsigned long timeout;
 283
 284         timeout = jiffies + msecs_to_jiffies(1000);
 285         while (!(__raw_readl(reg) & bit)) {
 286                 if (time_after(jiffies, timeout))
 287                         return -1;
 288                 cpu_relax();
 289         }
 290         return 0;
 291 }
 292
 293 static unsigned
 294 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
 295 {
 296         struct omap2_mcspi      *mcspi;
 297         struct omap2_mcspi_cs   *cs = spi->controller_state;
 298         struct omap2_mcspi_dma  *mcspi_dma;
 299         unsigned int            count, c;
 300         unsigned long           base, tx_reg, rx_reg;
 301         int                     word_len, data_type, element_count;
 302         int                     elements = 0;
 303         u32                     l;
 304         u8                      * rx;
 305         const u8                * tx;
 306         void __iomem            *chstat_reg;
 307
 308         mcspi = spi_master_get_devdata(spi->master);
 309         mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 310         l = mcspi_cached_chconf0(spi);
 311
 312         chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
 313
 314         count = xfer->len;
 315         c = count;
 316         word_len = cs->word_len;
 317
 318         base = cs->phys;
 319         tx_reg = base + OMAP2_MCSPI_TX0;
 320         rx_reg = base + OMAP2_MCSPI_RX0;
 321         rx = xfer->rx_buf;
 322         tx = xfer->tx_buf;
 323
 324         if (word_len <= 8) {
 325                 data_type = OMAP_DMA_DATA_TYPE_S8;
 326                 element_count = count;
 327         } else if (word_len <= 16) {
 328                 data_type = OMAP_DMA_DATA_TYPE_S16;
 329                 element_count = count >> 1;
 330         } else /* word_len <= 32 */ {
 331                 data_type = OMAP_DMA_DATA_TYPE_S32;
 332                 element_count = count >> 2;
 333         }
 334
 335         if (tx != NULL) {
 336                 omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel,
 337                                 data_type, element_count, 1,
 338                                 OMAP_DMA_SYNC_ELEMENT,
 339                                 mcspi_dma->dma_tx_sync_dev, 0);
 340
 341                 omap_set_dma_dest_params(mcspi_dma->dma_tx_channel, 0,
 342                                 OMAP_DMA_AMODE_CONSTANT,
 343                                 tx_reg, 0, 0);
 344
 345                 omap_set_dma_src_params(mcspi_dma->dma_tx_channel, 0,
 346                                 OMAP_DMA_AMODE_POST_INC,
 347                                 xfer->tx_dma, 0, 0);
 348         }
 349
 350         if (rx != NULL) {
 351                 elements = element_count - 1;
 352                 if (l & OMAP2_MCSPI_CHCONF_TURBO)
 353                         elements--;
 354
 355                 omap_set_dma_transfer_params(mcspi_dma->dma_rx_channel,
 356                                 data_type, elements, 1,
 357                                 OMAP_DMA_SYNC_ELEMENT,
 358                                 mcspi_dma->dma_rx_sync_dev, 1);
 359
 360                 omap_set_dma_src_params(mcspi_dma->dma_rx_channel, 0,
 361                                 OMAP_DMA_AMODE_CONSTANT,
 362                                 rx_reg, 0, 0);
 363
 364                 omap_set_dma_dest_params(mcspi_dma->dma_rx_channel, 0,
 365                                 OMAP_DMA_AMODE_POST_INC,
 366                                 xfer->rx_dma, 0, 0);
 367         }
 368
 369         if (tx != NULL) {
 370                 omap_start_dma(mcspi_dma->dma_tx_channel);
 371                 omap2_mcspi_set_dma_req(spi, 0, 1);
 372         }
 373
 374         if (rx != NULL) {
 375                 omap_start_dma(mcspi_dma->dma_rx_channel);
 376                 omap2_mcspi_set_dma_req(spi, 1, 1);
 377         }
 378
 379         if (tx != NULL) {
 380                 wait_for_completion(&mcspi_dma->dma_tx_completion);
 381                 dma_unmap_single(&spi->dev, xfer->tx_dma, count, DMA_TO_DEVICE);
 382
 383                 /* for TX_ONLY mode, be sure all words have shifted out */
 384                 if (rx == NULL) {
 385                         if (mcspi_wait_for_reg_bit(chstat_reg,
 386                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0)
 387                                 dev_err(&spi->dev, "TXS timed out\n");
 388                         else if (mcspi_wait_for_reg_bit(chstat_reg,
 389                                                 OMAP2_MCSPI_CHSTAT_EOT) < 0)
 390                                 dev_err(&spi->dev, "EOT timed out\n");
 391                 }
 392         }
 393
 394         if (rx != NULL) {
 395                 wait_for_completion(&mcspi_dma->dma_rx_completion);
 396                 dma_unmap_single(&spi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE);
 397                 omap2_mcspi_set_enable(spi, 0);
 398
 399                 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
 400
 401                         if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 402                                    & OMAP2_MCSPI_CHSTAT_RXS)) {
 403                                 u32 w;
 404
 405                                 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 406                                 if (word_len <= 8)
 407                                         ((u8 *)xfer->rx_buf)[elements++] = w;
 408                                 else if (word_len <= 16)
 409                                         ((u16 *)xfer->rx_buf)[elements++] = w;
 410                                 else /* word_len <= 32 */
 411                                         ((u32 *)xfer->rx_buf)[elements++] = w;
 412                         } else {
 413                                 dev_err(&spi->dev,
 414                                         "DMA RX penultimate word empty");
 415                                 count -= (word_len <= 8)  ? 2 :
 416                                         (word_len <= 16) ? 4 :
 417                                         /* word_len <= 32 */ 8;
 418                                 omap2_mcspi_set_enable(spi, 1);
 419                                 return count;
 420                         }
 421                 }
 422
 423                 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
 424                                 & OMAP2_MCSPI_CHSTAT_RXS)) {
 425                         u32 w;
 426
 427                         w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
 428                         if (word_len <= 8)
 429                                 ((u8 *)xfer->rx_buf)[elements] = w;
 430                         else if (word_len <= 16)
 431                                 ((u16 *)xfer->rx_buf)[elements] = w;
 432                         else /* word_len <= 32 */
 433                                 ((u32 *)xfer->rx_buf)[elements] = w;
 434                 } else {
 435                         dev_err(&spi->dev, "DMA RX last word empty");
 436                         count -= (word_len <= 8)  ? 1 :
 437                                  (word_len <= 16) ? 2 :
 438                                /* word_len <= 32 */ 4;
 439                 }
 440                 omap2_mcspi_set_enable(spi, 1);
 441         }
 442         return count;
 443 }
 444
 445 static unsigned
 446 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
 447 {
 448         struct omap2_mcspi      *mcspi;
 449         struct omap2_mcspi_cs   *cs = spi->controller_state;
 450         unsigned int            count, c;
 451         u32                     l;
 452         void __iomem            *base = cs->base;
 453         void __iomem            *tx_reg;
 454         void __iomem            *rx_reg;
 455         void __iomem            *chstat_reg;
 456         int                     word_len;
 457
 458         mcspi = spi_master_get_devdata(spi->master);
 459         count = xfer->len;
 460         c = count;
 461         word_len = cs->word_len;
 462
 463         l = mcspi_cached_chconf0(spi);
 464
 465         /* We store the pre-calculated register addresses on stack to speed
 466          * up the transfer loop. */
 467         tx_reg          = base + OMAP2_MCSPI_TX0;
 468         rx_reg          = base + OMAP2_MCSPI_RX0;
 469         chstat_reg      = base + OMAP2_MCSPI_CHSTAT0;
 470
 471         if (c < (word_len>>3))
 472                 return 0;
 473
 474         if (word_len <= 8) {
 475                 u8              *rx;
 476                 const u8        *tx;
 477
 478                 rx = xfer->rx_buf;
 479                 tx = xfer->tx_buf;
 480
 481                 do {
 482                         c -= 1;
 483                         if (tx != NULL) {
 484                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 485                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 486                                         dev_err(&spi->dev, "TXS timed out\n");
 487                                         goto out;
 488                                 }
 489                                 dev_vdbg(&spi->dev, "write-%d %02x\n",
 490                                                 word_len, *tx);
 491                                 __raw_writel(*tx++, tx_reg);
 492                         }
 493                         if (rx != NULL) {
 494                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 495                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 496                                         dev_err(&spi->dev, "RXS timed out\n");
 497                                         goto out;
 498                                 }
 499
 500                                 if (c == 1 && tx == NULL &&
 501                                     (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 502                                         omap2_mcspi_set_enable(spi, 0);
 503                                         *rx++ = __raw_readl(rx_reg);
 504                                         dev_vdbg(&spi->dev, "read-%d %02x\n",
 505                                                     word_len, *(rx - 1));
 506                                         if (mcspi_wait_for_reg_bit(chstat_reg,
 507                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 508                                                 dev_err(&spi->dev,
 509                                                         "RXS timed out\n");
 510                                                 goto out;
 511                                         }
 512                                         c = 0;
 513                                 } else if (c == 0 && tx == NULL) {
 514                                         omap2_mcspi_set_enable(spi, 0);
 515                                 }
 516
 517                                 *rx++ = __raw_readl(rx_reg);
 518                                 dev_vdbg(&spi->dev, "read-%d %02x\n",
 519                                                 word_len, *(rx - 1));
 520                         }
 521                 } while (c);
 522         } else if (word_len <= 16) {
 523                 u16             *rx;
 524                 const u16       *tx;
 525
 526                 rx = xfer->rx_buf;
 527                 tx = xfer->tx_buf;
 528                 do {
 529                         c -= 2;
 530                         if (tx != NULL) {
 531                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 532                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 533                                         dev_err(&spi->dev, "TXS timed out\n");
 534                                         goto out;
 535                                 }
 536                                 dev_vdbg(&spi->dev, "write-%d %04x\n",
 537                                                 word_len, *tx);
 538                                 __raw_writel(*tx++, tx_reg);
 539                         }
 540                         if (rx != NULL) {
 541                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 542                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 543                                         dev_err(&spi->dev, "RXS timed out\n");
 544                                         goto out;
 545                                 }
 546
 547                                 if (c == 2 && tx == NULL &&
 548                                     (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 549                                         omap2_mcspi_set_enable(spi, 0);
 550                                         *rx++ = __raw_readl(rx_reg);
 551                                         dev_vdbg(&spi->dev, "read-%d %04x\n",
 552                                                     word_len, *(rx - 1));
 553                                         if (mcspi_wait_for_reg_bit(chstat_reg,
 554                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 555                                                 dev_err(&spi->dev,
 556                                                         "RXS timed out\n");
 557                                                 goto out;
 558                                         }
 559                                         c = 0;
 560                                 } else if (c == 0 && tx == NULL) {
 561                                         omap2_mcspi_set_enable(spi, 0);
 562                                 }
 563
 564                                 *rx++ = __raw_readl(rx_reg);
 565                                 dev_vdbg(&spi->dev, "read-%d %04x\n",
 566                                                 word_len, *(rx - 1));
 567                         }
 568                 } while (c >= 2);
 569         } else if (word_len <= 32) {
 570                 u32             *rx;
 571                 const u32       *tx;
 572
 573                 rx = xfer->rx_buf;
 574                 tx = xfer->tx_buf;
 575                 do {
 576                         c -= 4;
 577                         if (tx != NULL) {
 578                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 579                                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 580                                         dev_err(&spi->dev, "TXS timed out\n");
 581                                         goto out;
 582                                 }
 583                                 dev_vdbg(&spi->dev, "write-%d %08x\n",
 584                                                 word_len, *tx);
 585                                 __raw_writel(*tx++, tx_reg);
 586                         }
 587                         if (rx != NULL) {
 588                                 if (mcspi_wait_for_reg_bit(chstat_reg,
 589                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 590                                         dev_err(&spi->dev, "RXS timed out\n");
 591                                         goto out;
 592                                 }
 593
 594                                 if (c == 4 && tx == NULL &&
 595                                     (l & OMAP2_MCSPI_CHCONF_TURBO)) {
 596                                         omap2_mcspi_set_enable(spi, 0);
 597                                         *rx++ = __raw_readl(rx_reg);
 598                                         dev_vdbg(&spi->dev, "read-%d %08x\n",
 599                                                     word_len, *(rx - 1));
 600                                         if (mcspi_wait_for_reg_bit(chstat_reg,
 601                                                 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
 602                                                 dev_err(&spi->dev,
 603                                                         "RXS timed out\n");
 604                                                 goto out;
 605                                         }
 606                                         c = 0;
 607                                 } else if (c == 0 && tx == NULL) {
 608                                         omap2_mcspi_set_enable(spi, 0);
 609                                 }
 610
 611                                 *rx++ = __raw_readl(rx_reg);
 612                                 dev_vdbg(&spi->dev, "read-%d %08x\n",
 613                                                 word_len, *(rx - 1));
 614                         }
 615                 } while (c >= 4);
 616         }
 617
 618         /* for TX_ONLY mode, be sure all words have shifted out */
 619         if (xfer->rx_buf == NULL) {
 620                 if (mcspi_wait_for_reg_bit(chstat_reg,
 621                                 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
 622                         dev_err(&spi->dev, "TXS timed out\n");
 623                 } else if (mcspi_wait_for_reg_bit(chstat_reg,
 624                                 OMAP2_MCSPI_CHSTAT_EOT) < 0)
 625                         dev_err(&spi->dev, "EOT timed out\n");
 626
 627                 /* disable chan to purge rx datas received in TX_ONLY transfer,
 628                  * otherwise these rx datas will affect the direct following
 629                  * RX_ONLY transfer.
 630                  */
 631                 omap2_mcspi_set_enable(spi, 0);
 632         }
 633 out:
 634         omap2_mcspi_set_enable(spi, 1);
 635         return count - c;
 636 }
 637
 638 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 639 {
 640         u32 div;
 641
 642         for (div = 0; div < 15; div++)
 643                 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 644                         return div;
 645
 646         return 15;
 647 }
 648
 649 /* called only when no transfer is active to this device */
 650 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
 651                 struct spi_transfer *t)
 652 {
 653         struct omap2_mcspi_cs *cs = spi->controller_state;
 654         struct omap2_mcspi *mcspi;
 655         struct spi_master *spi_cntrl;
 656         u32 l = 0, div = 0;
 657         u8 word_len = spi->bits_per_word;
 658         u32 speed_hz = spi->max_speed_hz;
 659
 660         mcspi = spi_master_get_devdata(spi->master);
 661         spi_cntrl = mcspi->master;
 662
 663         if (t != NULL && t->bits_per_word)
 664                 word_len = t->bits_per_word;
 665
 666         cs->word_len = word_len;
 667
 668         if (t && t->speed_hz)
 669                 speed_hz = t->speed_hz;
 670
 671         speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 672         div = omap2_mcspi_calc_divisor(speed_hz);
 673
 674         l = mcspi_cached_chconf0(spi);
 675
 676         /* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
 677          * REVISIT: this controller could support SPI_3WIRE mode.
 678          */
 679         l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
 680         l |= OMAP2_MCSPI_CHCONF_DPE0;
 681
 682         /* wordlength */
 683         l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
 684         l |= (word_len - 1) << 7;
 685
 686         /* set chipselect polarity; manage with FORCE */
 687         if (!(spi->mode & SPI_CS_HIGH))
 688                 l |= OMAP2_MCSPI_CHCONF_EPOL;   /* active-low; normal */
 689         else
 690                 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
 691
 692         /* set clock divisor */
 693         l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
 694         l |= div << 2;
 695
 696         /* set SPI mode 0..3 */
 697         if (spi->mode & SPI_CPOL)
 698                 l |= OMAP2_MCSPI_CHCONF_POL;
 699         else
 700                 l &= ~OMAP2_MCSPI_CHCONF_POL;
 701         if (spi->mode & SPI_CPHA)
 702                 l |= OMAP2_MCSPI_CHCONF_PHA;
 703         else
 704                 l &= ~OMAP2_MCSPI_CHCONF_PHA;
 705
 706         mcspi_write_chconf0(spi, l);
 707
 708         dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
 709                         OMAP2_MCSPI_MAX_FREQ >> div,
 710                         (spi->mode & SPI_CPHA) ? "trailing" : "leading",
 711                         (spi->mode & SPI_CPOL) ? "inverted" : "normal");
 712
 713         return 0;
 714 }
 715
 716 static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data)
 717 {
 718         struct spi_device       *spi = data;
 719         struct omap2_mcspi      *mcspi;
 720         struct omap2_mcspi_dma  *mcspi_dma;
 721
 722         mcspi = spi_master_get_devdata(spi->master);
 723         mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
 724
 725         complete(&mcspi_dma->dma_rx_completion);
 726
 727         /* We must disable the DMA RX request */
 728         omap2_mcspi_set_dma_req(spi, 1, 0);
 729 }
 730
 731 static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data)
 732 {
 733         struct spi_device       *spi = data;
 734         struct omap2_mcspi      *mcspi;
 735         struct omap2_mcspi_dma  *mcspi_dma;
 736
 737         mcspi = spi_master_get_devdata(spi->master);
 738         mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
 739
 740         complete(&mcspi_dma->dma_tx_completion);
 741
 742         /* We must disable the DMA TX request */
 743         omap2_mcspi_set_dma_req(spi, 0, 0);
 744 }
 745
 746 static int omap2_mcspi_request_dma(struct spi_device *spi)
 747 {
 748         struct spi_master       *master = spi->master;
 749         struct omap2_mcspi      *mcspi;
 750         struct omap2_mcspi_dma  *mcspi_dma;
 751
 752         mcspi = spi_master_get_devdata(master);
 753         mcspi_dma = mcspi->dma_channels + spi->chip_select;
 754
 755         if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX",
 756                         omap2_mcspi_dma_rx_callback, spi,
 757                         &mcspi_dma->dma_rx_channel)) {
 758                 dev_err(&spi->dev, "no RX DMA channel for McSPI\n");
 759                 return -EAGAIN;
 760         }
 761
 762         if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX",
 763                         omap2_mcspi_dma_tx_callback, spi,
 764                         &mcspi_dma->dma_tx_channel)) {
 765                 omap_free_dma(mcspi_dma->dma_rx_channel);
 766                 mcspi_dma->dma_rx_channel = -1;
 767                 dev_err(&spi->dev, "no TX DMA channel for McSPI\n");
 768                 return -EAGAIN;
 769         }
 770
 771         init_completion(&mcspi_dma->dma_rx_completion);
 772         init_completion(&mcspi_dma->dma_tx_completion);
 773
 774         return 0;
 775 }
 776
 777 static int omap2_mcspi_setup(struct spi_device *spi)
 778 {
 779         int                     ret;
 780         struct omap2_mcspi      *mcspi;
 781         struct omap2_mcspi_dma  *mcspi_dma;
 782         struct omap2_mcspi_cs   *cs = spi->controller_state;
 783
 784         if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
 785                 dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
 786                         spi->bits_per_word);
 787                 return -EINVAL;
 788         }
 789
 790         mcspi = spi_master_get_devdata(spi->master);
 791         mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 792
 793         if (!cs) {
 794                 cs = kzalloc(sizeof *cs, GFP_KERNEL);
 795                 if (!cs)
 796                         return -ENOMEM;
 797                 cs->base = mcspi->base + spi->chip_select * 0x14;
 798                 cs->phys = mcspi->phys + spi->chip_select * 0x14;
 799                 cs->chconf0 = 0;
 800                 spi->controller_state = cs;
 801                 /* Link this to context save list */
 802                 list_add_tail(&cs->node,
 803                         &omap2_mcspi_ctx[mcspi->master->bus_num - 1].cs);
 804         }
 805
 806         if (mcspi_dma->dma_rx_channel == -1
 807                         || mcspi_dma->dma_tx_channel == -1) {
 808                 ret = omap2_mcspi_request_dma(spi);
 809                 if (ret < 0)
 810                         return ret;
 811         }
 812
 813         ret = omap2_mcspi_enable_clocks(mcspi);
 814         if (ret < 0)
 815                 return ret;
 816
 817         ret = omap2_mcspi_setup_transfer(spi, NULL);
 818         omap2_mcspi_disable_clocks(mcspi);
 819
 820         return ret;
 821 }
 822
 823 static void omap2_mcspi_cleanup(struct spi_device *spi)
 824 {
 825         struct omap2_mcspi      *mcspi;
 826         struct omap2_mcspi_dma  *mcspi_dma;
 827         struct omap2_mcspi_cs   *cs;
 828
 829         mcspi = spi_master_get_devdata(spi->master);
 830
 831         if (spi->controller_state) {
 832                 /* Unlink controller state from context save list */
 833                 cs = spi->controller_state;
 834                 list_del(&cs->node);
 835
 836                 kfree(spi->controller_state);
 837         }
 838
 839         if (spi->chip_select < spi->master->num_chipselect) {
 840                 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 841
 842                 if (mcspi_dma->dma_rx_channel != -1) {
 843                         omap_free_dma(mcspi_dma->dma_rx_channel);
 844                         mcspi_dma->dma_rx_channel = -1;
 845                 }
 846                 if (mcspi_dma->dma_tx_channel != -1) {
 847                         omap_free_dma(mcspi_dma->dma_tx_channel);
 848                         mcspi_dma->dma_tx_channel = -1;
 849                 }
 850         }
 851 }
 852
 853 static void omap2_mcspi_work(struct work_struct *work)
 854 {
 855         struct omap2_mcspi      *mcspi;
 856
 857         mcspi = container_of(work, struct omap2_mcspi, work);
 858
 859         if (omap2_mcspi_enable_clocks(mcspi) < 0)
 860                 return;
 861
 862         spin_lock_irq(&mcspi->lock);
 863
 864         /* We only enable one channel at a time -- the one whose message is
 865          * at the head of the queue -- although this controller would gladly
 866          * arbitrate among multiple channels.  This corresponds to "single
 867          * channel" master mode.  As a side effect, we need to manage the
 868          * chipselect with the FORCE bit ... CS != channel enable.
 869          */
 870         while (!list_empty(&mcspi->msg_queue)) {
 871                 struct spi_message              *m;
 872                 struct spi_device               *spi;
 873                 struct spi_transfer             *t = NULL;
 874                 int                             cs_active = 0;
 875                 struct omap2_mcspi_cs           *cs;
 876                 struct omap2_mcspi_device_config *cd;
 877                 int                             par_override = 0;
 878                 int                             status = 0;
 879                 u32                             chconf;
 880
 881                 m = container_of(mcspi->msg_queue.next, struct spi_message,
 882                                  queue);
 883
 884                 list_del_init(&m->queue);
 885                 spin_unlock_irq(&mcspi->lock);
 886
 887                 spi = m->spi;
 888                 cs = spi->controller_state;
 889                 cd = spi->controller_data;
 890
 891                 omap2_mcspi_set_enable(spi, 1);
 892                 list_for_each_entry(t, &m->transfers, transfer_list) {
 893                         if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
 894                                 status = -EINVAL;
 895                                 break;
 896                         }
 897                         if (par_override || t->speed_hz || t->bits_per_word) {
 898                                 par_override = 1;
 899                                 status = omap2_mcspi_setup_transfer(spi, t);
 900                                 if (status < 0)
 901                                         break;
 902                                 if (!t->speed_hz && !t->bits_per_word)
 903                                         par_override = 0;
 904                         }
 905
 906                         if (!cs_active) {
 907                                 omap2_mcspi_force_cs(spi, 1);
 908                                 cs_active = 1;
 909                         }
 910
 911                         chconf = mcspi_cached_chconf0(spi);
 912                         chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
 913                         chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
 914
 915                         if (t->tx_buf == NULL)
 916                                 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
 917                         else if (t->rx_buf == NULL)
 918                                 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
 919
 920                         if (cd && cd->turbo_mode && t->tx_buf == NULL) {
 921                                 /* Turbo mode is for more than one word */
 922                                 if (t->len > ((cs->word_len + 7) >> 3))
 923                                         chconf |= OMAP2_MCSPI_CHCONF_TURBO;
 924                         }
 925
 926                         mcspi_write_chconf0(spi, chconf);
 927
 928                         if (t->len) {
 929                                 unsigned        count;
 930
 931                                 /* RX_ONLY mode needs dummy data in TX reg */
 932                                 if (t->tx_buf == NULL)
 933                                         __raw_writel(0, cs->base
 934                                                         + OMAP2_MCSPI_TX0);
 935
 936                                 if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
 937                                         count = omap2_mcspi_txrx_dma(spi, t);
 938                                 else
 939                                         count = omap2_mcspi_txrx_pio(spi, t);
 940                                 m->actual_length += count;
 941
 942                                 if (count != t->len) {
 943                                         status = -EIO;
 944                                         break;
 945                                 }
 946                         }
 947
 948                         if (t->delay_usecs)
 949                                 udelay(t->delay_usecs);
 950
 951                         /* ignore the "leave it on after last xfer" hint */
 952                         if (t->cs_change) {
 953                                 omap2_mcspi_force_cs(spi, 0);
 954                                 cs_active = 0;
 955                         }
 956                 }
 957
 958                 /* Restore defaults if they were overriden */
 959                 if (par_override) {
 960                         par_override = 0;
 961                         status = omap2_mcspi_setup_transfer(spi, NULL);
 962                 }
 963
 964                 if (cs_active)
 965                         omap2_mcspi_force_cs(spi, 0);
 966
 967                 omap2_mcspi_set_enable(spi, 0);
 968
 969                 m->status = status;
 970                 m->complete(m->context);
 971
 972                 spin_lock_irq(&mcspi->lock);
 973         }
 974
 975         spin_unlock_irq(&mcspi->lock);
 976
 977         omap2_mcspi_disable_clocks(mcspi);
 978 }
 979
 980 static int omap2_mcspi_transfer(struct spi_device *spi, struct spi_message *m)
 981 {
 982         struct omap2_mcspi      *mcspi;
 983         unsigned long           flags;
 984         struct spi_transfer     *t;
 985
 986         m->actual_length = 0;
 987         m->status = 0;
 988
 989         /* reject invalid messages and transfers */
 990         if (list_empty(&m->transfers) || !m->complete)
 991                 return -EINVAL;
 992         list_for_each_entry(t, &m->transfers, transfer_list) {
 993                 const void      *tx_buf = t->tx_buf;
 994                 void            *rx_buf = t->rx_buf;
 995                 unsigned        len = t->len;
 996
 997                 if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
 998                                 || (len && !(rx_buf || tx_buf))
 999                                 || (t->bits_per_word &&
1000                                         (  t->bits_per_word < 4
1001                                         || t->bits_per_word > 32))) {
1002                         dev_dbg(&spi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1003                                         t->speed_hz,
1004                                         len,
1005                                         tx_buf ? "tx" : "",
1006                                         rx_buf ? "rx" : "",
1007                                         t->bits_per_word);
1008                         return -EINVAL;
1009                 }
1010                 if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
1011                         dev_dbg(&spi->dev, "speed_hz %d below minimum %d Hz\n",
1012                                 t->speed_hz,
1013                                 OMAP2_MCSPI_MAX_FREQ >> 15);
1014                         return -EINVAL;
1015                 }
1016
1017                 if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1018                         continue;
1019
1020                 if (tx_buf != NULL) {
1021                         t->tx_dma = dma_map_single(&spi->dev, (void *) tx_buf,
1022                                         len, DMA_TO_DEVICE);
1023                         if (dma_mapping_error(&spi->dev, t->tx_dma)) {
1024                                 dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
1025                                                 'T', len);
1026                                 return -EINVAL;
1027                         }
1028                 }
1029                 if (rx_buf != NULL) {
1030                         t->rx_dma = dma_map_single(&spi->dev, rx_buf, t->len,
1031                                         DMA_FROM_DEVICE);
1032                         if (dma_mapping_error(&spi->dev, t->rx_dma)) {
1033                                 dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
1034                                                 'R', len);
1035                                 if (tx_buf != NULL)
1036                                         dma_unmap_single(&spi->dev, t->tx_dma,
1037                                                         len, DMA_TO_DEVICE);
1038                                 return -EINVAL;
1039                         }
1040                 }
1041         }
1042
1043         mcspi = spi_master_get_devdata(spi->master);
1044
1045         spin_lock_irqsave(&mcspi->lock, flags);
1046         list_add_tail(&m->queue, &mcspi->msg_queue);
1047         queue_work(mcspi->wq, &mcspi->work);
1048         spin_unlock_irqrestore(&mcspi->lock, flags);
1049
1050         return 0;
1051 }
1052
1053 static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1054 {
1055         struct spi_master       *master = mcspi->master;
1056         u32                     tmp;
1057         int ret = 0;
1058
1059         ret = omap2_mcspi_enable_clocks(mcspi);
1060         if (ret < 0)
1061                 return ret;
1062
1063         tmp = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1064         mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, tmp);
1065         omap2_mcspi_ctx[master->bus_num - 1].wakeupenable = tmp;
1066
1067         omap2_mcspi_set_master_mode(master);
1068         omap2_mcspi_disable_clocks(mcspi);
1069         return 0;
1070 }
1071
1072 static int omap_mcspi_runtime_resume(struct device *dev)
1073 {
1074         struct omap2_mcspi      *mcspi;
1075         struct spi_master       *master;
1076
1077         master = dev_get_drvdata(dev);
1078         mcspi = spi_master_get_devdata(master);
1079         omap2_mcspi_restore_ctx(mcspi);
1080
1081         return 0;
1082 }
1083
1084 static struct omap2_mcspi_platform_config omap2_pdata = {
1085         .regs_offset = 0,
1086 };
1087
1088 static struct omap2_mcspi_platform_config omap4_pdata = {
1089         .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1090 };
1091
1092 static const struct of_device_id omap_mcspi_of_match[] = {
1093         {
1094                 .compatible = "ti,omap2-mcspi",
1095                 .data = &omap2_pdata,
1096         },
1097         {
1098                 .compatible = "ti,omap4-mcspi",
1099                 .data = &omap4_pdata,
1100         },
1101         { },
1102 };
1103 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1104
1105 static int __init omap2_mcspi_probe(struct platform_device *pdev)
1106 {
1107         struct spi_master       *master;
1108         struct omap2_mcspi_platform_config *pdata;
1109         struct omap2_mcspi      *mcspi;
1110         struct resource         *r;
1111         int                     status = 0, i;
1112         char                    wq_name[20];
1113         u32                     regs_offset = 0;
1114         static int              bus_num = 1;
1115         struct device_node      *node = pdev->dev.of_node;
1116         const struct of_device_id *match;
1117
1118         master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1119         if (master == NULL) {
1120                 dev_dbg(&pdev->dev, "master allocation failed\n");
1121                 return -ENOMEM;
1122         }
1123
1124         /* the spi->mode bits understood by this driver: */
1125         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1126
1127         master->setup = omap2_mcspi_setup;
1128         master->transfer = omap2_mcspi_transfer;
1129         master->cleanup = omap2_mcspi_cleanup;
1130         master->dev.of_node = node;
1131
1132         match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1133         if (match) {
1134                 u32 num_cs = 1; /* default number of chipselect */
1135                 pdata = match->data;
1136
1137                 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1138                 master->num_chipselect = num_cs;
1139                 master->bus_num = bus_num++;
1140         } else {
1141                 pdata = pdev->dev.platform_data;
1142                 master->num_chipselect = pdata->num_cs;
1143                 if (pdev->id != -1)
1144                         master->bus_num = pdev->id;
1145         }
1146         regs_offset = pdata->regs_offset;
1147
1148         dev_set_drvdata(&pdev->dev, master);
1149
1150         mcspi = spi_master_get_devdata(master);
1151         mcspi->master = master;
1152
1153         sprintf(wq_name, "omap2_mcspi/%d", master->bus_num);
1154         mcspi->wq = alloc_workqueue(wq_name, WQ_MEM_RECLAIM, 1);
1155         if (mcspi->wq == NULL) {
1156                 status = -ENOMEM;
1157                 goto free_master;
1158         }
1159
1160         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1161         if (r == NULL) {
1162                 status = -ENODEV;
1163                 goto free_master;
1164         }
1165
1166         r->start += regs_offset;
1167         r->end += regs_offset;
1168         mcspi->phys = r->start;
1169         if (!request_mem_region(r->start, resource_size(r),
1170                                 dev_name(&pdev->dev))) {
1171                 status = -EBUSY;
1172                 goto free_master;
1173         }
1174
1175         mcspi->base = ioremap(r->start, resource_size(r));
1176         if (!mcspi->base) {
1177                 dev_dbg(&pdev->dev, "can't ioremap MCSPI\n");
1178                 status = -ENOMEM;
1179                 goto release_region;
1180         }
1181
1182         mcspi->dev = &pdev->dev;
1183         INIT_WORK(&mcspi->work, omap2_mcspi_work);
1184
1185         spin_lock_init(&mcspi->lock);
1186         INIT_LIST_HEAD(&mcspi->msg_queue);
1187         INIT_LIST_HEAD(&omap2_mcspi_ctx[master->bus_num - 1].cs);
1188
1189         mcspi->dma_channels = kcalloc(master->num_chipselect,
1190                         sizeof(struct omap2_mcspi_dma),
1191                         GFP_KERNEL);
1192
1193         if (mcspi->dma_channels == NULL)
1194                 goto unmap_io;
1195
1196         for (i = 0; i < master->num_chipselect; i++) {
1197                 char dma_ch_name[14];
1198                 struct resource *dma_res;
1199
1200                 sprintf(dma_ch_name, "rx%d", i);
1201                 dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1202                                                         dma_ch_name);
1203                 if (!dma_res) {
1204                         dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
1205                         status = -ENODEV;
1206                         break;
1207                 }
1208
1209                 mcspi->dma_channels[i].dma_rx_channel = -1;
1210                 mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
1211                 sprintf(dma_ch_name, "tx%d", i);
1212                 dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1213                                                         dma_ch_name);
1214                 if (!dma_res) {
1215                         dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
1216                         status = -ENODEV;
1217                         break;
1218                 }
1219
1220                 mcspi->dma_channels[i].dma_tx_channel = -1;
1221                 mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start;
1222         }
1223
1224         if (status < 0)
1225                 goto dma_chnl_free;
1226
1227         pm_runtime_enable(&pdev->dev);
1228
1229         if (status || omap2_mcspi_master_setup(mcspi) < 0)
1230                 goto disable_pm;
1231
1232         status = spi_register_master(master);
1233         if (status < 0)
1234                 goto err_spi_register;
1235
1236         return status;
1237
1238 err_spi_register:
1239         spi_master_put(master);
1240 disable_pm:
1241         pm_runtime_disable(&pdev->dev);
1242 dma_chnl_free:
1243         kfree(mcspi->dma_channels);
1244 unmap_io:
1245         iounmap(mcspi->base);
1246 release_region:
1247         release_mem_region(r->start, resource_size(r));
1248 free_master:
1249         kfree(master);
1250         platform_set_drvdata(pdev, NULL);
1251         return status;
1252 }
1253
1254 static int __exit omap2_mcspi_remove(struct platform_device *pdev)
1255 {
1256         struct spi_master       *master;
1257         struct omap2_mcspi      *mcspi;
1258         struct omap2_mcspi_dma  *dma_channels;
1259         struct resource         *r;
1260         void __iomem *base;
1261
1262         master = dev_get_drvdata(&pdev->dev);
1263         mcspi = spi_master_get_devdata(master);
1264         dma_channels = mcspi->dma_channels;
1265
1266         omap2_mcspi_disable_clocks(mcspi);
1267         pm_runtime_disable(&pdev->dev);
1268         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1269         release_mem_region(r->start, resource_size(r));
1270
1271         base = mcspi->base;
1272         spi_unregister_master(master);
1273         iounmap(base);
1274         kfree(dma_channels);
1275         destroy_workqueue(mcspi->wq);
1276         platform_set_drvdata(pdev, NULL);
1277
1278         return 0;
1279 }
1280
1281 /* work with hotplug and coldplug */
1282 MODULE_ALIAS("platform:omap2_mcspi");
1283
1284 #ifdef  CONFIG_SUSPEND
1285 /*
1286  * When SPI wake up from off-mode, CS is in activate state. If it was in
1287  * unactive state when driver was suspend, then force it to unactive state at
1288  * wake up.
1289  */
1290 static int omap2_mcspi_resume(struct device *dev)
1291 {
1292         struct spi_master       *master = dev_get_drvdata(dev);
1293         struct omap2_mcspi      *mcspi = spi_master_get_devdata(master);
1294         struct omap2_mcspi_cs *cs;
1295
1296         omap2_mcspi_enable_clocks(mcspi);
1297         list_for_each_entry(cs, &omap2_mcspi_ctx[master->bus_num - 1].cs,
1298                             node) {
1299                 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1300
1301                         /*
1302                          * We need to toggle CS state for OMAP take this
1303                          * change in account.
1304                          */
1305                         MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 1);
1306                         __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1307                         MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 0);
1308                         __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1309                 }
1310         }
1311         omap2_mcspi_disable_clocks(mcspi);
1312         return 0;
1313 }
1314 #else
1315 #define omap2_mcspi_resume      NULL
1316 #endif
1317
1318 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1319         .resume = omap2_mcspi_resume,
1320         .runtime_resume = omap_mcspi_runtime_resume,
1321 };
1322
1323 static struct platform_driver omap2_mcspi_driver = {
1324         .driver = {
1325                 .name =         "omap2_mcspi",
1326                 .owner =        THIS_MODULE,
1327                 .pm =           &omap2_mcspi_pm_ops,
1328                 .of_match_table = omap_mcspi_of_match,
1329         },
1330         .remove =       __exit_p(omap2_mcspi_remove),
1331 };
1332
1333
1334 static int __init omap2_mcspi_init(void)
1335 {
1336         return platform_driver_probe(&omap2_mcspi_driver, omap2_mcspi_probe);
1337 }
1338 subsys_initcall(omap2_mcspi_init);
1339
1340 static void __exit omap2_mcspi_exit(void)
1341 {
1342         platform_driver_unregister(&omap2_mcspi_driver);
1343
1344 }
1345 module_exit(omap2_mcspi_exit);
1346
1347 MODULE_LICENSE("GPL");