drivers/spi/spi_s3c24xx.c

   1 /* linux/drivers/spi/spi_s3c24xx.c
   2  *
   3  * Copyright (c) 2006 Ben Dooks
   4  * Copyright 2006-2009 Simtec Electronics
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11 */
  12
  13 #include <linux/init.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/delay.h>
  18 #include <linux/errno.h>
  19 #include <linux/err.h>
  20 #include <linux/clk.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/gpio.h>
  23 #include <linux/io.h>
  24 #include <linux/slab.h>
  25
  26 #include <linux/spi/spi.h>
  27 #include <linux/spi/spi_bitbang.h>
  28
  29 #include <plat/regs-spi.h>
  30 #include <mach/spi.h>
  31
  32 #include <plat/fiq.h>
  33 #include <asm/fiq.h>
  34
  35 #include "spi_s3c24xx_fiq.h"
  36
  37 /**
  38  * s3c24xx_spi_devstate - per device data
  39  * @hz: Last frequency calculated for @sppre field.
  40  * @mode: Last mode setting for the @spcon field.
  41  * @spcon: Value to write to the SPCON register.
  42  * @sppre: Value to write to the SPPRE register.
  43  */
  44 struct s3c24xx_spi_devstate {
  45         unsigned int    hz;
  46         unsigned int    mode;
  47         u8              spcon;
  48         u8              sppre;
  49 };
  50
  51 enum spi_fiq_mode {
  52         FIQ_MODE_NONE   = 0,
  53         FIQ_MODE_TX     = 1,
  54         FIQ_MODE_RX     = 2,
  55         FIQ_MODE_TXRX   = 3,
  56 };
  57
  58 struct s3c24xx_spi {
  59         /* bitbang has to be first */
  60         struct spi_bitbang       bitbang;
  61         struct completion        done;
  62
  63         void __iomem            *regs;
  64         int                      irq;
  65         int                      len;
  66         int                      count;
  67
  68         struct fiq_handler       fiq_handler;
  69         enum spi_fiq_mode        fiq_mode;
  70         unsigned char            fiq_inuse;
  71         unsigned char            fiq_claimed;
  72
  73         void                    (*set_cs)(struct s3c2410_spi_info *spi,
  74                                           int cs, int pol);
  75
  76         /* data buffers */
  77         const unsigned char     *tx;
  78         unsigned char           *rx;
  79
  80         struct clk              *clk;
  81         struct resource         *ioarea;
  82         struct spi_master       *master;
  83         struct spi_device       *curdev;
  84         struct device           *dev;
  85         struct s3c2410_spi_info *pdata;
  86 };
  87
  88
  89 #define SPCON_DEFAULT (S3C2410_SPCON_MSTR | S3C2410_SPCON_SMOD_INT)
  90 #define SPPIN_DEFAULT (S3C2410_SPPIN_KEEP)
  91
  92 static inline struct s3c24xx_spi *to_hw(struct spi_device *sdev)
  93 {
  94         return spi_master_get_devdata(sdev->master);
  95 }
  96
  97 static void s3c24xx_spi_gpiocs(struct s3c2410_spi_info *spi, int cs, int pol)
  98 {
  99         gpio_set_value(spi->pin_cs, pol);
 100 }
 101
 102 static void s3c24xx_spi_chipsel(struct spi_device *spi, int value)
 103 {
 104         struct s3c24xx_spi_devstate *cs = spi->controller_state;
 105         struct s3c24xx_spi *hw = to_hw(spi);
 106         unsigned int cspol = spi->mode & SPI_CS_HIGH ? 1 : 0;
 107
 108         /* change the chipselect state and the state of the spi engine clock */
 109
 110         switch (value) {
 111         case BITBANG_CS_INACTIVE:
 112                 hw->set_cs(hw->pdata, spi->chip_select, cspol^1);
 113                 writeb(cs->spcon, hw->regs + S3C2410_SPCON);
 114                 break;
 115
 116         case BITBANG_CS_ACTIVE:
 117                 writeb(cs->spcon | S3C2410_SPCON_ENSCK,
 118                        hw->regs + S3C2410_SPCON);
 119                 hw->set_cs(hw->pdata, spi->chip_select, cspol);
 120                 break;
 121         }
 122 }
 123
 124 static int s3c24xx_spi_update_state(struct spi_device *spi,
 125                                     struct spi_transfer *t)
 126 {
 127         struct s3c24xx_spi *hw = to_hw(spi);
 128         struct s3c24xx_spi_devstate *cs = spi->controller_state;
 129         unsigned int bpw;
 130         unsigned int hz;
 131         unsigned int div;
 132         unsigned long clk;
 133
 134         bpw = t ? t->bits_per_word : spi->bits_per_word;
 135         hz  = t ? t->speed_hz : spi->max_speed_hz;
 136
 137         if (!bpw)
 138                 bpw = 8;
 139
 140         if (!hz)
 141                 hz = spi->max_speed_hz;
 142
 143         if (bpw != 8) {
 144                 dev_err(&spi->dev, "invalid bits-per-word (%d)\n", bpw);
 145                 return -EINVAL;
 146         }
 147
 148         if (spi->mode != cs->mode) {
 149                 u8 spcon = SPCON_DEFAULT | S3C2410_SPCON_ENSCK;
 150
 151                 if (spi->mode & SPI_CPHA)
 152                         spcon |= S3C2410_SPCON_CPHA_FMTB;
 153
 154                 if (spi->mode & SPI_CPOL)
 155                         spcon |= S3C2410_SPCON_CPOL_HIGH;
 156
 157                 cs->mode = spi->mode;
 158                 cs->spcon = spcon;
 159         }
 160
 161         if (cs->hz != hz) {
 162                 clk = clk_get_rate(hw->clk);
 163                 div = DIV_ROUND_UP(clk, hz * 2) - 1;
 164
 165                 if (div > 255)
 166                         div = 255;
 167
 168                 dev_dbg(&spi->dev, "pre-scaler=%d (wanted %d, got %ld)\n",
 169                         div, hz, clk / (2 * (div + 1)));
 170
 171                 cs->hz = hz;
 172                 cs->sppre = div;
 173         }
 174
 175         return 0;
 176 }
 177
 178 static int s3c24xx_spi_setupxfer(struct spi_device *spi,
 179                                  struct spi_transfer *t)
 180 {
 181         struct s3c24xx_spi_devstate *cs = spi->controller_state;
 182         struct s3c24xx_spi *hw = to_hw(spi);
 183         int ret;
 184
 185         ret = s3c24xx_spi_update_state(spi, t);
 186         if (!ret)
 187                 writeb(cs->sppre, hw->regs + S3C2410_SPPRE);
 188
 189         return ret;
 190 }
 191
 192 static int s3c24xx_spi_setup(struct spi_device *spi)
 193 {
 194         struct s3c24xx_spi_devstate *cs = spi->controller_state;
 195         struct s3c24xx_spi *hw = to_hw(spi);
 196         int ret;
 197
 198         /* allocate settings on the first call */
 199         if (!cs) {
 200                 cs = kzalloc(sizeof(struct s3c24xx_spi_devstate), GFP_KERNEL);
 201                 if (!cs) {
 202                         dev_err(&spi->dev, "no memory for controller state\n");
 203                         return -ENOMEM;
 204                 }
 205
 206                 cs->spcon = SPCON_DEFAULT;
 207                 cs->hz = -1;
 208                 spi->controller_state = cs;
 209         }
 210
 211         /* initialise the state from the device */
 212         ret = s3c24xx_spi_update_state(spi, NULL);
 213         if (ret)
 214                 return ret;
 215
 216         spin_lock(&hw->bitbang.lock);
 217         if (!hw->bitbang.busy) {
 218                 hw->bitbang.chipselect(spi, BITBANG_CS_INACTIVE);
 219                 /* need to ndelay for 0.5 clocktick ? */
 220         }
 221         spin_unlock(&hw->bitbang.lock);
 222
 223         return 0;
 224 }
 225
 226 static void s3c24xx_spi_cleanup(struct spi_device *spi)
 227 {
 228         kfree(spi->controller_state);
 229 }
 230
 231 static inline unsigned int hw_txbyte(struct s3c24xx_spi *hw, int count)
 232 {
 233         return hw->tx ? hw->tx[count] : 0;
 234 }
 235
 236 #ifdef CONFIG_SPI_S3C24XX_FIQ
 237 /* Support for FIQ based pseudo-DMA to improve the transfer speed.
 238  *
 239  * This code uses the assembly helper in spi_s3c24xx_spi.S which is
 240  * used by the FIQ core to move data between main memory and the peripheral
 241  * block. Since this is code running on the processor, there is no problem
 242  * with cache coherency of the buffers, so we can use any buffer we like.
 243  */
 244
 245 /**
 246  * struct spi_fiq_code - FIQ code and header
 247  * @length: The length of the code fragment, excluding this header.
 248  * @ack_offset: The offset from @data to the word to place the IRQ ACK bit at.
 249  * @data: The code itself to install as a FIQ handler.
 250  */
 251 struct spi_fiq_code {
 252         u32     length;
 253         u32     ack_offset;
 254         u8      data[0];
 255 };
 256
 257 extern struct spi_fiq_code s3c24xx_spi_fiq_txrx;
 258 extern struct spi_fiq_code s3c24xx_spi_fiq_tx;
 259 extern struct spi_fiq_code s3c24xx_spi_fiq_rx;
 260
 261 /**
 262  * ack_bit - turn IRQ into IRQ acknowledgement bit
 263  * @irq: The interrupt number
 264  *
 265  * Returns the bit to write to the interrupt acknowledge register.
 266  */
 267 static inline u32 ack_bit(unsigned int irq)
 268 {
 269         return 1 << (irq - IRQ_EINT0);
 270 }
 271
 272 /**
 273  * s3c24xx_spi_tryfiq - attempt to claim and setup FIQ for transfer
 274  * @hw: The hardware state.
 275  *
 276  * Claim the FIQ handler (only one can be active at any one time) and
 277  * then setup the correct transfer code for this transfer.
 278  *
 279  * This call updates all the necessary state information if successful,
 280  * so the caller does not need to do anything more than start the transfer
 281  * as normal, since the IRQ will have been re-routed to the FIQ handler.
 282 */
 283 void s3c24xx_spi_tryfiq(struct s3c24xx_spi *hw)
 284 {
 285         struct pt_regs regs;
 286         enum spi_fiq_mode mode;
 287         struct spi_fiq_code *code;
 288         int ret;
 289
 290         if (!hw->fiq_claimed) {
 291                 /* try and claim fiq if we haven't got it, and if not
 292                  * then return and simply use another transfer method */
 293
 294                 ret = claim_fiq(&hw->fiq_handler);
 295                 if (ret)
 296                         return;
 297         }
 298
 299         if (hw->tx && !hw->rx)
 300                 mode = FIQ_MODE_TX;
 301         else if (hw->rx && !hw->tx)
 302                 mode = FIQ_MODE_RX;
 303         else
 304                 mode = FIQ_MODE_TXRX;
 305
 306         regs.uregs[fiq_rspi] = (long)hw->regs;
 307         regs.uregs[fiq_rrx]  = (long)hw->rx;
 308         regs.uregs[fiq_rtx]  = (long)hw->tx + 1;
 309         regs.uregs[fiq_rcount] = hw->len - 1;
 310         regs.uregs[fiq_rirq] = (long)S3C24XX_VA_IRQ;
 311
 312         set_fiq_regs(&regs);
 313
 314         if (hw->fiq_mode != mode) {
 315                 u32 *ack_ptr;
 316
 317                 hw->fiq_mode = mode;
 318
 319                 switch (mode) {
 320                 case FIQ_MODE_TX:
 321                         code = &s3c24xx_spi_fiq_tx;
 322                         break;
 323                 case FIQ_MODE_RX:
 324                         code = &s3c24xx_spi_fiq_rx;
 325                         break;
 326                 case FIQ_MODE_TXRX:
 327                         code = &s3c24xx_spi_fiq_txrx;
 328                         break;
 329                 default:
 330                         code = NULL;
 331                 }
 332
 333                 BUG_ON(!code);
 334
 335                 ack_ptr = (u32 *)&code->data[code->ack_offset];
 336                 *ack_ptr = ack_bit(hw->irq);
 337
 338                 set_fiq_handler(&code->data, code->length);
 339         }
 340
 341         s3c24xx_set_fiq(hw->irq, true);
 342
 343         hw->fiq_mode = mode;
 344         hw->fiq_inuse = 1;
 345 }
 346
 347 /**
 348  * s3c24xx_spi_fiqop - FIQ core code callback
 349  * @pw: Data registered with the handler
 350  * @release: Whether this is a release or a return.
 351  *
 352  * Called by the FIQ code when another module wants to use the FIQ, so
 353  * return whether we are currently using this or not and then update our
 354  * internal state.
 355  */
 356 static int s3c24xx_spi_fiqop(void *pw, int release)
 357 {
 358         struct s3c24xx_spi *hw = pw;
 359         int ret = 0;
 360
 361         if (release) {
 362                 if (hw->fiq_inuse)
 363                         ret = -EBUSY;
 364
 365                 /* note, we do not need to unroute the FIQ, as the FIQ
 366                  * vector code de-routes it to signal the end of transfer */
 367
 368                 hw->fiq_mode = FIQ_MODE_NONE;
 369                 hw->fiq_claimed = 0;
 370         } else {
 371                 hw->fiq_claimed = 1;
 372         }
 373
 374         return ret;
 375 }
 376
 377 /**
 378  * s3c24xx_spi_initfiq - setup the information for the FIQ core
 379  * @hw: The hardware state.
 380  *
 381  * Setup the fiq_handler block to pass to the FIQ core.
 382  */
 383 static inline void s3c24xx_spi_initfiq(struct s3c24xx_spi *hw)
 384 {
 385         hw->fiq_handler.dev_id = hw;
 386         hw->fiq_handler.name = dev_name(hw->dev);
 387         hw->fiq_handler.fiq_op = s3c24xx_spi_fiqop;
 388 }
 389
 390 /**
 391  * s3c24xx_spi_usefiq - return if we should be using FIQ.
 392  * @hw: The hardware state.
 393  *
 394  * Return true if the platform data specifies whether this channel is
 395  * allowed to use the FIQ.
 396  */
 397 static inline bool s3c24xx_spi_usefiq(struct s3c24xx_spi *hw)
 398 {
 399         return hw->pdata->use_fiq;
 400 }
 401
 402 /**
 403  * s3c24xx_spi_usingfiq - return if channel is using FIQ
 404  * @spi: The hardware state.
 405  *
 406  * Return whether the channel is currently using the FIQ (separate from
 407  * whether the FIQ is claimed).
 408  */
 409 static inline bool s3c24xx_spi_usingfiq(struct s3c24xx_spi *spi)
 410 {
 411         return spi->fiq_inuse;
 412 }
 413 #else
 414
 415 static inline void s3c24xx_spi_initfiq(struct s3c24xx_spi *s) { }
 416 static inline void s3c24xx_spi_tryfiq(struct s3c24xx_spi *s) { }
 417 static inline bool s3c24xx_spi_usefiq(struct s3c24xx_spi *s) { return false; }
 418 static inline bool s3c24xx_spi_usingfiq(struct s3c24xx_spi *s) { return false; }
 419
 420 #endif /* CONFIG_SPI_S3C24XX_FIQ */
 421
 422 static int s3c24xx_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
 423 {
 424         struct s3c24xx_spi *hw = to_hw(spi);
 425
 426         hw->tx = t->tx_buf;
 427         hw->rx = t->rx_buf;
 428         hw->len = t->len;
 429         hw->count = 0;
 430
 431         init_completion(&hw->done);
 432
 433         hw->fiq_inuse = 0;
 434         if (s3c24xx_spi_usefiq(hw) && t->len >= 3)
 435                 s3c24xx_spi_tryfiq(hw);
 436
 437         /* send the first byte */
 438         writeb(hw_txbyte(hw, 0), hw->regs + S3C2410_SPTDAT);
 439
 440         wait_for_completion(&hw->done);
 441         return hw->count;
 442 }
 443
 444 static irqreturn_t s3c24xx_spi_irq(int irq, void *dev)
 445 {
 446         struct s3c24xx_spi *hw = dev;
 447         unsigned int spsta = readb(hw->regs + S3C2410_SPSTA);
 448         unsigned int count = hw->count;
 449
 450         if (spsta & S3C2410_SPSTA_DCOL) {
 451                 dev_dbg(hw->dev, "data-collision\n");
 452                 complete(&hw->done);
 453                 goto irq_done;
 454         }
 455
 456         if (!(spsta & S3C2410_SPSTA_READY)) {
 457                 dev_dbg(hw->dev, "spi not ready for tx?\n");
 458                 complete(&hw->done);
 459                 goto irq_done;
 460         }
 461
 462         if (!s3c24xx_spi_usingfiq(hw)) {
 463                 hw->count++;
 464
 465                 if (hw->rx)
 466                         hw->rx[count] = readb(hw->regs + S3C2410_SPRDAT);
 467
 468                 count++;
 469
 470                 if (count < hw->len)
 471                         writeb(hw_txbyte(hw, count), hw->regs + S3C2410_SPTDAT);
 472                 else
 473                         complete(&hw->done);
 474         } else {
 475                 hw->count = hw->len;
 476                 hw->fiq_inuse = 0;
 477
 478                 if (hw->rx)
 479                         hw->rx[hw->len-1] = readb(hw->regs + S3C2410_SPRDAT);
 480
 481                 complete(&hw->done);
 482         }
 483
 484  irq_done:
 485         return IRQ_HANDLED;
 486 }
 487
 488 static void s3c24xx_spi_initialsetup(struct s3c24xx_spi *hw)
 489 {
 490         /* for the moment, permanently enable the clock */
 491
 492         clk_enable(hw->clk);
 493
 494         /* program defaults into the registers */
 495
 496         writeb(0xff, hw->regs + S3C2410_SPPRE);
 497         writeb(SPPIN_DEFAULT, hw->regs + S3C2410_SPPIN);
 498         writeb(SPCON_DEFAULT, hw->regs + S3C2410_SPCON);
 499
 500         if (hw->pdata) {
 501                 if (hw->set_cs == s3c24xx_spi_gpiocs)
 502                         gpio_direction_output(hw->pdata->pin_cs, 1);
 503
 504                 if (hw->pdata->gpio_setup)
 505                         hw->pdata->gpio_setup(hw->pdata, 1);
 506         }
 507 }
 508
 509 static int __init s3c24xx_spi_probe(struct platform_device *pdev)
 510 {
 511         struct s3c2410_spi_info *pdata;
 512         struct s3c24xx_spi *hw;
 513         struct spi_master *master;
 514         struct resource *res;
 515         int err = 0;
 516
 517         master = spi_alloc_master(&pdev->dev, sizeof(struct s3c24xx_spi));
 518         if (master == NULL) {
 519                 dev_err(&pdev->dev, "No memory for spi_master\n");
 520                 err = -ENOMEM;
 521                 goto err_nomem;
 522         }
 523
 524         hw = spi_master_get_devdata(master);
 525         memset(hw, 0, sizeof(struct s3c24xx_spi));
 526
 527         hw->master = spi_master_get(master);
 528         hw->pdata = pdata = pdev->dev.platform_data;
 529         hw->dev = &pdev->dev;
 530
 531         if (pdata == NULL) {
 532                 dev_err(&pdev->dev, "No platform data supplied\n");
 533                 err = -ENOENT;
 534                 goto err_no_pdata;
 535         }
 536
 537         platform_set_drvdata(pdev, hw);
 538         init_completion(&hw->done);
 539
 540         /* initialise fiq handler */
 541
 542         s3c24xx_spi_initfiq(hw);
 543
 544         /* setup the master state. */
 545
 546         /* the spi->mode bits understood by this driver: */
 547         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 548
 549         master->num_chipselect = hw->pdata->num_cs;
 550         master->bus_num = pdata->bus_num;
 551
 552         /* setup the state for the bitbang driver */
 553
 554         hw->bitbang.master         = hw->master;
 555         hw->bitbang.setup_transfer = s3c24xx_spi_setupxfer;
 556         hw->bitbang.chipselect     = s3c24xx_spi_chipsel;
 557         hw->bitbang.txrx_bufs      = s3c24xx_spi_txrx;
 558
 559         hw->master->setup  = s3c24xx_spi_setup;
 560         hw->master->cleanup = s3c24xx_spi_cleanup;
 561
 562         dev_dbg(hw->dev, "bitbang at %p\n", &hw->bitbang);
 563
 564         /* find and map our resources */
 565
 566         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 567         if (res == NULL) {
 568                 dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
 569                 err = -ENOENT;
 570                 goto err_no_iores;
 571         }
 572
 573         hw->ioarea = request_mem_region(res->start, resource_size(res),
 574                                         pdev->name);
 575
 576         if (hw->ioarea == NULL) {
 577                 dev_err(&pdev->dev, "Cannot reserve region\n");
 578                 err = -ENXIO;
 579                 goto err_no_iores;
 580         }
 581
 582         hw->regs = ioremap(res->start, resource_size(res));
 583         if (hw->regs == NULL) {
 584                 dev_err(&pdev->dev, "Cannot map IO\n");
 585                 err = -ENXIO;
 586                 goto err_no_iomap;
 587         }
 588
 589         hw->irq = platform_get_irq(pdev, 0);
 590         if (hw->irq < 0) {
 591                 dev_err(&pdev->dev, "No IRQ specified\n");
 592                 err = -ENOENT;
 593                 goto err_no_irq;
 594         }
 595
 596         err = request_irq(hw->irq, s3c24xx_spi_irq, 0, pdev->name, hw);
 597         if (err) {
 598                 dev_err(&pdev->dev, "Cannot claim IRQ\n");
 599                 goto err_no_irq;
 600         }
 601
 602         hw->clk = clk_get(&pdev->dev, "spi");
 603         if (IS_ERR(hw->clk)) {
 604                 dev_err(&pdev->dev, "No clock for device\n");
 605                 err = PTR_ERR(hw->clk);
 606                 goto err_no_clk;
 607         }
 608
 609         /* setup any gpio we can */
 610
 611         if (!pdata->set_cs) {
 612                 if (pdata->pin_cs < 0) {
 613                         dev_err(&pdev->dev, "No chipselect pin\n");
 614                         goto err_register;
 615                 }
 616
 617                 err = gpio_request(pdata->pin_cs, dev_name(&pdev->dev));
 618                 if (err) {
 619                         dev_err(&pdev->dev, "Failed to get gpio for cs\n");
 620                         goto err_register;
 621                 }
 622
 623                 hw->set_cs = s3c24xx_spi_gpiocs;
 624                 gpio_direction_output(pdata->pin_cs, 1);
 625         } else
 626                 hw->set_cs = pdata->set_cs;
 627
 628         s3c24xx_spi_initialsetup(hw);
 629
 630         /* register our spi controller */
 631
 632         err = spi_bitbang_start(&hw->bitbang);
 633         if (err) {
 634                 dev_err(&pdev->dev, "Failed to register SPI master\n");
 635                 goto err_register;
 636         }
 637
 638         return 0;
 639
 640  err_register:
 641         if (hw->set_cs == s3c24xx_spi_gpiocs)
 642                 gpio_free(pdata->pin_cs);
 643
 644         clk_disable(hw->clk);
 645         clk_put(hw->clk);
 646
 647  err_no_clk:
 648         free_irq(hw->irq, hw);
 649
 650  err_no_irq:
 651         iounmap(hw->regs);
 652
 653  err_no_iomap:
 654         release_resource(hw->ioarea);
 655         kfree(hw->ioarea);
 656
 657  err_no_iores:
 658  err_no_pdata:
 659         spi_master_put(hw->master);
 660
 661  err_nomem:
 662         return err;
 663 }
 664
 665 static int __exit s3c24xx_spi_remove(struct platform_device *dev)
 666 {
 667         struct s3c24xx_spi *hw = platform_get_drvdata(dev);
 668
 669         platform_set_drvdata(dev, NULL);
 670
 671         spi_unregister_master(hw->master);
 672
 673         clk_disable(hw->clk);
 674         clk_put(hw->clk);
 675
 676         free_irq(hw->irq, hw);
 677         iounmap(hw->regs);
 678
 679         if (hw->set_cs == s3c24xx_spi_gpiocs)
 680                 gpio_free(hw->pdata->pin_cs);
 681
 682         release_resource(hw->ioarea);
 683         kfree(hw->ioarea);
 684
 685         spi_master_put(hw->master);
 686         return 0;
 687 }
 688
 689
 690 #ifdef CONFIG_PM
 691
 692 static int s3c24xx_spi_suspend(struct device *dev)
 693 {
 694         struct s3c24xx_spi *hw = platform_get_drvdata(to_platform_device(dev));
 695
 696         if (hw->pdata && hw->pdata->gpio_setup)
 697                 hw->pdata->gpio_setup(hw->pdata, 0);
 698
 699         clk_disable(hw->clk);
 700         return 0;
 701 }
 702
 703 static int s3c24xx_spi_resume(struct device *dev)
 704 {
 705         struct s3c24xx_spi *hw = platform_get_drvdata(to_platform_device(dev));
 706
 707         s3c24xx_spi_initialsetup(hw);
 708         return 0;
 709 }
 710
 711 static const struct dev_pm_ops s3c24xx_spi_pmops = {
 712         .suspend        = s3c24xx_spi_suspend,
 713         .resume         = s3c24xx_spi_resume,
 714 };
 715
 716 #define S3C24XX_SPI_PMOPS &s3c24xx_spi_pmops
 717 #else
 718 #define S3C24XX_SPI_PMOPS NULL
 719 #endif /* CONFIG_PM */
 720
 721 MODULE_ALIAS("platform:s3c2410-spi");
 722 static struct platform_driver s3c24xx_spi_driver = {
 723         .remove         = __exit_p(s3c24xx_spi_remove),
 724         .driver         = {
 725                 .name   = "s3c2410-spi",
 726                 .owner  = THIS_MODULE,
 727                 .pm     = S3C24XX_SPI_PMOPS,
 728         },
 729 };
 730
 731 static int __init s3c24xx_spi_init(void)
 732 {
 733         return platform_driver_probe(&s3c24xx_spi_driver, s3c24xx_spi_probe);
 734 }
 735
 736 static void __exit s3c24xx_spi_exit(void)
 737 {
 738         platform_driver_unregister(&s3c24xx_spi_driver);
 739 }
 740
 741 module_init(s3c24xx_spi_init);
 742 module_exit(s3c24xx_spi_exit);
 743
 744 MODULE_DESCRIPTION("S3C24XX SPI Driver");
 745 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 746 MODULE_LICENSE("GPL");