drivers/mtd/nand/raw/r852.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright © 2009 - Maxim Levitsky
   4  * driver for Ricoh xD readers
   5  */
   6
   7 #define DRV_NAME "r852"
   8 #define pr_fmt(fmt)  DRV_NAME ": " fmt
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/jiffies.h>
  13 #include <linux/workqueue.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/pci.h>
  16 #include <linux/pci_ids.h>
  17 #include <linux/delay.h>
  18 #include <linux/slab.h>
  19 #include <asm/byteorder.h>
  20 #include <linux/sched.h>
  21 #include "sm_common.h"
  22 #include "r852.h"
  23
  24
  25 static bool r852_enable_dma = 1;
  26 module_param(r852_enable_dma, bool, S_IRUGO);
  27 MODULE_PARM_DESC(r852_enable_dma, "Enable usage of the DMA (default)");
  28
  29 static int debug;
  30 module_param(debug, int, S_IRUGO | S_IWUSR);
  31 MODULE_PARM_DESC(debug, "Debug level (0-2)");
  32
  33 /* read register */
  34 static inline uint8_t r852_read_reg(struct r852_device *dev, int address)
  35 {
  36         uint8_t reg = readb(dev->mmio + address);
  37         return reg;
  38 }
  39
  40 /* write register */
  41 static inline void r852_write_reg(struct r852_device *dev,
  42                                                 int address, uint8_t value)
  43 {
  44         writeb(value, dev->mmio + address);
  45 }
  46
  47
  48 /* read dword sized register */
  49 static inline uint32_t r852_read_reg_dword(struct r852_device *dev, int address)
  50 {
  51         uint32_t reg = le32_to_cpu(readl(dev->mmio + address));
  52         return reg;
  53 }
  54
  55 /* write dword sized register */
  56 static inline void r852_write_reg_dword(struct r852_device *dev,
  57                                                         int address, uint32_t value)
  58 {
  59         writel(cpu_to_le32(value), dev->mmio + address);
  60 }
  61
  62 /* returns pointer to our private structure */
  63 static inline struct r852_device *r852_get_dev(struct mtd_info *mtd)
  64 {
  65         struct nand_chip *chip = mtd_to_nand(mtd);
  66         return nand_get_controller_data(chip);
  67 }
  68
  69
  70 /* check if controller supports dma */
  71 static void r852_dma_test(struct r852_device *dev)
  72 {
  73         dev->dma_usable = (r852_read_reg(dev, R852_DMA_CAP) &
  74                 (R852_DMA1 | R852_DMA2)) == (R852_DMA1 | R852_DMA2);
  75
  76         if (!dev->dma_usable)
  77                 message("Non dma capable device detected, dma disabled");
  78
  79         if (!r852_enable_dma) {
  80                 message("disabling dma on user request");
  81                 dev->dma_usable = 0;
  82         }
  83 }
  84
  85 /*
  86  * Enable dma. Enables ether first or second stage of the DMA,
  87  * Expects dev->dma_dir and dev->dma_state be set
  88  */
  89 static void r852_dma_enable(struct r852_device *dev)
  90 {
  91         uint8_t dma_reg, dma_irq_reg;
  92
  93         /* Set up dma settings */
  94         dma_reg = r852_read_reg_dword(dev, R852_DMA_SETTINGS);
  95         dma_reg &= ~(R852_DMA_READ | R852_DMA_INTERNAL | R852_DMA_MEMORY);
  96
  97         if (dev->dma_dir)
  98                 dma_reg |= R852_DMA_READ;
  99
 100         if (dev->dma_state == DMA_INTERNAL) {
 101                 dma_reg |= R852_DMA_INTERNAL;
 102                 /* Precaution to make sure HW doesn't write */
 103                         /* to random kernel memory */
 104                 r852_write_reg_dword(dev, R852_DMA_ADDR,
 105                         cpu_to_le32(dev->phys_bounce_buffer));
 106         } else {
 107                 dma_reg |= R852_DMA_MEMORY;
 108                 r852_write_reg_dword(dev, R852_DMA_ADDR,
 109                         cpu_to_le32(dev->phys_dma_addr));
 110         }
 111
 112         /* Precaution: make sure write reached the device */
 113         r852_read_reg_dword(dev, R852_DMA_ADDR);
 114
 115         r852_write_reg_dword(dev, R852_DMA_SETTINGS, dma_reg);
 116
 117         /* Set dma irq */
 118         dma_irq_reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
 119         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
 120                 dma_irq_reg |
 121                 R852_DMA_IRQ_INTERNAL |
 122                 R852_DMA_IRQ_ERROR |
 123                 R852_DMA_IRQ_MEMORY);
 124 }
 125
 126 /*
 127  * Disable dma, called from the interrupt handler, which specifies
 128  * success of the operation via 'error' argument
 129  */
 130 static void r852_dma_done(struct r852_device *dev, int error)
 131 {
 132         WARN_ON(dev->dma_stage == 0);
 133
 134         r852_write_reg_dword(dev, R852_DMA_IRQ_STA,
 135                         r852_read_reg_dword(dev, R852_DMA_IRQ_STA));
 136
 137         r852_write_reg_dword(dev, R852_DMA_SETTINGS, 0);
 138         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE, 0);
 139
 140         /* Precaution to make sure HW doesn't write to random kernel memory */
 141         r852_write_reg_dword(dev, R852_DMA_ADDR,
 142                 cpu_to_le32(dev->phys_bounce_buffer));
 143         r852_read_reg_dword(dev, R852_DMA_ADDR);
 144
 145         dev->dma_error = error;
 146         dev->dma_stage = 0;
 147
 148         if (dev->phys_dma_addr && dev->phys_dma_addr != dev->phys_bounce_buffer)
 149                 dma_unmap_single(&dev->pci_dev->dev, dev->phys_dma_addr,
 150                         R852_DMA_LEN,
 151                         dev->dma_dir ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
 152 }
 153
 154 /*
 155  * Wait, till dma is done, which includes both phases of it
 156  */
 157 static int r852_dma_wait(struct r852_device *dev)
 158 {
 159         long timeout = wait_for_completion_timeout(&dev->dma_done,
 160                                 msecs_to_jiffies(1000));
 161         if (!timeout) {
 162                 dbg("timeout waiting for DMA interrupt");
 163                 return -ETIMEDOUT;
 164         }
 165
 166         return 0;
 167 }
 168
 169 /*
 170  * Read/Write one page using dma. Only pages can be read (512 bytes)
 171 */
 172 static void r852_do_dma(struct r852_device *dev, uint8_t *buf, int do_read)
 173 {
 174         int bounce = 0;
 175         unsigned long flags;
 176         int error;
 177
 178         dev->dma_error = 0;
 179
 180         /* Set dma direction */
 181         dev->dma_dir = do_read;
 182         dev->dma_stage = 1;
 183         reinit_completion(&dev->dma_done);
 184
 185         dbg_verbose("doing dma %s ", do_read ? "read" : "write");
 186
 187         /* Set initial dma state: for reading first fill on board buffer,
 188           from device, for writes first fill the buffer  from memory*/
 189         dev->dma_state = do_read ? DMA_INTERNAL : DMA_MEMORY;
 190
 191         /* if incoming buffer is not page aligned, we should do bounce */
 192         if ((unsigned long)buf & (R852_DMA_LEN-1))
 193                 bounce = 1;
 194
 195         if (!bounce) {
 196                 dev->phys_dma_addr = dma_map_single(&dev->pci_dev->dev, buf,
 197                         R852_DMA_LEN,
 198                         do_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
 199                 if (dma_mapping_error(&dev->pci_dev->dev, dev->phys_dma_addr))
 200                         bounce = 1;
 201         }
 202
 203         if (bounce) {
 204                 dbg_verbose("dma: using bounce buffer");
 205                 dev->phys_dma_addr = dev->phys_bounce_buffer;
 206                 if (!do_read)
 207                         memcpy(dev->bounce_buffer, buf, R852_DMA_LEN);
 208         }
 209
 210         /* Enable DMA */
 211         spin_lock_irqsave(&dev->irqlock, flags);
 212         r852_dma_enable(dev);
 213         spin_unlock_irqrestore(&dev->irqlock, flags);
 214
 215         /* Wait till complete */
 216         error = r852_dma_wait(dev);
 217
 218         if (error) {
 219                 r852_dma_done(dev, error);
 220                 return;
 221         }
 222
 223         if (do_read && bounce)
 224                 memcpy((void *)buf, dev->bounce_buffer, R852_DMA_LEN);
 225 }
 226
 227 /*
 228  * Program data lines of the nand chip to send data to it
 229  */
 230 static void r852_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
 231 {
 232         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 233         uint32_t reg;
 234
 235         /* Don't allow any access to hardware if we suspect card removal */
 236         if (dev->card_unstable)
 237                 return;
 238
 239         /* Special case for whole sector read */
 240         if (len == R852_DMA_LEN && dev->dma_usable) {
 241                 r852_do_dma(dev, (uint8_t *)buf, 0);
 242                 return;
 243         }
 244
 245         /* write DWORD chinks - faster */
 246         while (len >= 4) {
 247                 reg = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24;
 248                 r852_write_reg_dword(dev, R852_DATALINE, reg);
 249                 buf += 4;
 250                 len -= 4;
 251
 252         }
 253
 254         /* write rest */
 255         while (len > 0) {
 256                 r852_write_reg(dev, R852_DATALINE, *buf++);
 257                 len--;
 258         }
 259 }
 260
 261 /*
 262  * Read data lines of the nand chip to retrieve data
 263  */
 264 static void r852_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
 265 {
 266         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 267         uint32_t reg;
 268
 269         if (dev->card_unstable) {
 270                 /* since we can't signal error here, at least, return
 271                         predictable buffer */
 272                 memset(buf, 0, len);
 273                 return;
 274         }
 275
 276         /* special case for whole sector read */
 277         if (len == R852_DMA_LEN && dev->dma_usable) {
 278                 r852_do_dma(dev, buf, 1);
 279                 return;
 280         }
 281
 282         /* read in dword sized chunks */
 283         while (len >= 4) {
 284
 285                 reg = r852_read_reg_dword(dev, R852_DATALINE);
 286                 *buf++ = reg & 0xFF;
 287                 *buf++ = (reg >> 8) & 0xFF;
 288                 *buf++ = (reg >> 16) & 0xFF;
 289                 *buf++ = (reg >> 24) & 0xFF;
 290                 len -= 4;
 291         }
 292
 293         /* read the reset by bytes */
 294         while (len--)
 295                 *buf++ = r852_read_reg(dev, R852_DATALINE);
 296 }
 297
 298 /*
 299  * Read one byte from nand chip
 300  */
 301 static uint8_t r852_read_byte(struct nand_chip *chip)
 302 {
 303         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 304
 305         /* Same problem as in r852_read_buf.... */
 306         if (dev->card_unstable)
 307                 return 0;
 308
 309         return r852_read_reg(dev, R852_DATALINE);
 310 }
 311
 312 /*
 313  * Control several chip lines & send commands
 314  */
 315 static void r852_cmdctl(struct nand_chip *chip, int dat, unsigned int ctrl)
 316 {
 317         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 318
 319         if (dev->card_unstable)
 320                 return;
 321
 322         if (ctrl & NAND_CTRL_CHANGE) {
 323
 324                 dev->ctlreg &= ~(R852_CTL_DATA | R852_CTL_COMMAND |
 325                                  R852_CTL_ON | R852_CTL_CARDENABLE);
 326
 327                 if (ctrl & NAND_ALE)
 328                         dev->ctlreg |= R852_CTL_DATA;
 329
 330                 if (ctrl & NAND_CLE)
 331                         dev->ctlreg |= R852_CTL_COMMAND;
 332
 333                 if (ctrl & NAND_NCE)
 334                         dev->ctlreg |= (R852_CTL_CARDENABLE | R852_CTL_ON);
 335                 else
 336                         dev->ctlreg &= ~R852_CTL_WRITE;
 337
 338                 /* when write is stareted, enable write access */
 339                 if (dat == NAND_CMD_ERASE1)
 340                         dev->ctlreg |= R852_CTL_WRITE;
 341
 342                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 343         }
 344
 345          /* HACK: NAND_CMD_SEQIN is called without NAND_CTRL_CHANGE, but we need
 346                 to set write mode */
 347         if (dat == NAND_CMD_SEQIN && (dev->ctlreg & R852_CTL_COMMAND)) {
 348                 dev->ctlreg |= R852_CTL_WRITE;
 349                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 350         }
 351
 352         if (dat != NAND_CMD_NONE)
 353                 r852_write_reg(dev, R852_DATALINE, dat);
 354 }
 355
 356 /*
 357  * Wait till card is ready.
 358  * based on nand_wait, but returns errors on DMA error
 359  */
 360 static int r852_wait(struct nand_chip *chip)
 361 {
 362         struct r852_device *dev = nand_get_controller_data(chip);
 363
 364         unsigned long timeout;
 365         u8 status;
 366
 367         timeout = jiffies + msecs_to_jiffies(400);
 368
 369         while (time_before(jiffies, timeout))
 370                 if (chip->legacy.dev_ready(chip))
 371                         break;
 372
 373         nand_status_op(chip, &status);
 374
 375         /* Unfortunelly, no way to send detailed error status... */
 376         if (dev->dma_error) {
 377                 status |= NAND_STATUS_FAIL;
 378                 dev->dma_error = 0;
 379         }
 380         return status;
 381 }
 382
 383 /*
 384  * Check if card is ready
 385  */
 386
 387 static int r852_ready(struct nand_chip *chip)
 388 {
 389         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 390         return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY);
 391 }
 392
 393
 394 /*
 395  * Set ECC engine mode
 396 */
 397
 398 static void r852_ecc_hwctl(struct nand_chip *chip, int mode)
 399 {
 400         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 401
 402         if (dev->card_unstable)
 403                 return;
 404
 405         switch (mode) {
 406         case NAND_ECC_READ:
 407         case NAND_ECC_WRITE:
 408                 /* enable ecc generation/check*/
 409                 dev->ctlreg |= R852_CTL_ECC_ENABLE;
 410
 411                 /* flush ecc buffer */
 412                 r852_write_reg(dev, R852_CTL,
 413                         dev->ctlreg | R852_CTL_ECC_ACCESS);
 414
 415                 r852_read_reg_dword(dev, R852_DATALINE);
 416                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 417                 return;
 418
 419         case NAND_ECC_READSYN:
 420                 /* disable ecc generation */
 421                 dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
 422                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 423         }
 424 }
 425
 426 /*
 427  * Calculate ECC, only used for writes
 428  */
 429
 430 static int r852_ecc_calculate(struct nand_chip *chip, const uint8_t *dat,
 431                               uint8_t *ecc_code)
 432 {
 433         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 434         struct sm_oob *oob = (struct sm_oob *)ecc_code;
 435         uint32_t ecc1, ecc2;
 436
 437         if (dev->card_unstable)
 438                 return 0;
 439
 440         dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
 441         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
 442
 443         ecc1 = r852_read_reg_dword(dev, R852_DATALINE);
 444         ecc2 = r852_read_reg_dword(dev, R852_DATALINE);
 445
 446         oob->ecc1[0] = (ecc1) & 0xFF;
 447         oob->ecc1[1] = (ecc1 >> 8) & 0xFF;
 448         oob->ecc1[2] = (ecc1 >> 16) & 0xFF;
 449
 450         oob->ecc2[0] = (ecc2) & 0xFF;
 451         oob->ecc2[1] = (ecc2 >> 8) & 0xFF;
 452         oob->ecc2[2] = (ecc2 >> 16) & 0xFF;
 453
 454         r852_write_reg(dev, R852_CTL, dev->ctlreg);
 455         return 0;
 456 }
 457
 458 /*
 459  * Correct the data using ECC, hw did almost everything for us
 460  */
 461
 462 static int r852_ecc_correct(struct nand_chip *chip, uint8_t *dat,
 463                             uint8_t *read_ecc, uint8_t *calc_ecc)
 464 {
 465         uint32_t ecc_reg;
 466         uint8_t ecc_status, err_byte;
 467         int i, error = 0;
 468
 469         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 470
 471         if (dev->card_unstable)
 472                 return 0;
 473
 474         if (dev->dma_error) {
 475                 dev->dma_error = 0;
 476                 return -EIO;
 477         }
 478
 479         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
 480         ecc_reg = r852_read_reg_dword(dev, R852_DATALINE);
 481         r852_write_reg(dev, R852_CTL, dev->ctlreg);
 482
 483         for (i = 0 ; i <= 1 ; i++) {
 484
 485                 ecc_status = (ecc_reg >> 8) & 0xFF;
 486
 487                 /* ecc uncorrectable error */
 488                 if (ecc_status & R852_ECC_FAIL) {
 489                         dbg("ecc: unrecoverable error, in half %d", i);
 490                         error = -EBADMSG;
 491                         goto exit;
 492                 }
 493
 494                 /* correctable error */
 495                 if (ecc_status & R852_ECC_CORRECTABLE) {
 496
 497                         err_byte = ecc_reg & 0xFF;
 498                         dbg("ecc: recoverable error, "
 499                                 "in half %d, byte %d, bit %d", i,
 500                                 err_byte, ecc_status & R852_ECC_ERR_BIT_MSK);
 501
 502                         dat[err_byte] ^=
 503                                 1 << (ecc_status & R852_ECC_ERR_BIT_MSK);
 504                         error++;
 505                 }
 506
 507                 dat += 256;
 508                 ecc_reg >>= 16;
 509         }
 510 exit:
 511         return error;
 512 }
 513
 514 /*
 515  * This is copy of nand_read_oob_std
 516  * nand_read_oob_syndrome assumes we can send column address - we can't
 517  */
 518 static int r852_read_oob(struct nand_chip *chip, int page)
 519 {
 520         struct mtd_info *mtd = nand_to_mtd(chip);
 521
 522         return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
 523 }
 524
 525 /*
 526  * Start the nand engine
 527  */
 528
 529 static void r852_engine_enable(struct r852_device *dev)
 530 {
 531         if (r852_read_reg_dword(dev, R852_HW) & R852_HW_UNKNOWN) {
 532                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
 533                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
 534         } else {
 535                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
 536                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
 537         }
 538         msleep(300);
 539         r852_write_reg(dev, R852_CTL, 0);
 540 }
 541
 542
 543 /*
 544  * Stop the nand engine
 545  */
 546
 547 static void r852_engine_disable(struct r852_device *dev)
 548 {
 549         r852_write_reg_dword(dev, R852_HW, 0);
 550         r852_write_reg(dev, R852_CTL, R852_CTL_RESET);
 551 }
 552
 553 /*
 554  * Test if card is present
 555  */
 556
 557 static void r852_card_update_present(struct r852_device *dev)
 558 {
 559         unsigned long flags;
 560         uint8_t reg;
 561
 562         spin_lock_irqsave(&dev->irqlock, flags);
 563         reg = r852_read_reg(dev, R852_CARD_STA);
 564         dev->card_detected = !!(reg & R852_CARD_STA_PRESENT);
 565         spin_unlock_irqrestore(&dev->irqlock, flags);
 566 }
 567
 568 /*
 569  * Update card detection IRQ state according to current card state
 570  * which is read in r852_card_update_present
 571  */
 572 static void r852_update_card_detect(struct r852_device *dev)
 573 {
 574         int card_detect_reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
 575         dev->card_unstable = 0;
 576
 577         card_detect_reg &= ~(R852_CARD_IRQ_REMOVE | R852_CARD_IRQ_INSERT);
 578         card_detect_reg |= R852_CARD_IRQ_GENABLE;
 579
 580         card_detect_reg |= dev->card_detected ?
 581                 R852_CARD_IRQ_REMOVE : R852_CARD_IRQ_INSERT;
 582
 583         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, card_detect_reg);
 584 }
 585
 586 static ssize_t r852_media_type_show(struct device *sys_dev,
 587                         struct device_attribute *attr, char *buf)
 588 {
 589         struct mtd_info *mtd = container_of(sys_dev, struct mtd_info, dev);
 590         struct r852_device *dev = r852_get_dev(mtd);
 591         char *data = dev->sm ? "smartmedia" : "xd";
 592
 593         strcpy(buf, data);
 594         return strlen(data);
 595 }
 596
 597 static DEVICE_ATTR(media_type, S_IRUGO, r852_media_type_show, NULL);
 598
 599
 600 /* Detect properties of card in slot */
 601 static void r852_update_media_status(struct r852_device *dev)
 602 {
 603         uint8_t reg;
 604         unsigned long flags;
 605         int readonly;
 606
 607         spin_lock_irqsave(&dev->irqlock, flags);
 608         if (!dev->card_detected) {
 609                 message("card removed");
 610                 spin_unlock_irqrestore(&dev->irqlock, flags);
 611                 return ;
 612         }
 613
 614         readonly  = r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_RO;
 615         reg = r852_read_reg(dev, R852_DMA_CAP);
 616         dev->sm = (reg & (R852_DMA1 | R852_DMA2)) && (reg & R852_SMBIT);
 617
 618         message("detected %s %s card in slot",
 619                 dev->sm ? "SmartMedia" : "xD",
 620                 readonly ? "readonly" : "writeable");
 621
 622         dev->readonly = readonly;
 623         spin_unlock_irqrestore(&dev->irqlock, flags);
 624 }
 625
 626 /*
 627  * Register the nand device
 628  * Called when the card is detected
 629  */
 630 static int r852_register_nand_device(struct r852_device *dev)
 631 {
 632         struct mtd_info *mtd = nand_to_mtd(dev->chip);
 633
 634         WARN_ON(dev->card_registered);
 635
 636         mtd->dev.parent = &dev->pci_dev->dev;
 637
 638         if (dev->readonly)
 639                 dev->chip->options |= NAND_ROM;
 640
 641         r852_engine_enable(dev);
 642
 643         if (sm_register_device(mtd, dev->sm))
 644                 goto error1;
 645
 646         if (device_create_file(&mtd->dev, &dev_attr_media_type)) {
 647                 message("can't create media type sysfs attribute");
 648                 goto error3;
 649         }
 650
 651         dev->card_registered = 1;
 652         return 0;
 653 error3:
 654         nand_release(dev->chip);
 655 error1:
 656         /* Force card redetect */
 657         dev->card_detected = 0;
 658         return -1;
 659 }
 660
 661 /*
 662  * Unregister the card
 663  */
 664
 665 static void r852_unregister_nand_device(struct r852_device *dev)
 666 {
 667         struct mtd_info *mtd = nand_to_mtd(dev->chip);
 668
 669         if (!dev->card_registered)
 670                 return;
 671
 672         device_remove_file(&mtd->dev, &dev_attr_media_type);
 673         nand_release(dev->chip);
 674         r852_engine_disable(dev);
 675         dev->card_registered = 0;
 676 }
 677
 678 /* Card state updater */
 679 static void r852_card_detect_work(struct work_struct *work)
 680 {
 681         struct r852_device *dev =
 682                 container_of(work, struct r852_device, card_detect_work.work);
 683
 684         r852_card_update_present(dev);
 685         r852_update_card_detect(dev);
 686         dev->card_unstable = 0;
 687
 688         /* False alarm */
 689         if (dev->card_detected == dev->card_registered)
 690                 goto exit;
 691
 692         /* Read media properties */
 693         r852_update_media_status(dev);
 694
 695         /* Register the card */
 696         if (dev->card_detected)
 697                 r852_register_nand_device(dev);
 698         else
 699                 r852_unregister_nand_device(dev);
 700 exit:
 701         r852_update_card_detect(dev);
 702 }
 703
 704 /* Ack + disable IRQ generation */
 705 static void r852_disable_irqs(struct r852_device *dev)
 706 {
 707         uint8_t reg;
 708         reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
 709         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, reg & ~R852_CARD_IRQ_MASK);
 710
 711         reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
 712         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
 713                                         reg & ~R852_DMA_IRQ_MASK);
 714
 715         r852_write_reg(dev, R852_CARD_IRQ_STA, R852_CARD_IRQ_MASK);
 716         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, R852_DMA_IRQ_MASK);
 717 }
 718
 719 /* Interrupt handler */
 720 static irqreturn_t r852_irq(int irq, void *data)
 721 {
 722         struct r852_device *dev = (struct r852_device *)data;
 723
 724         uint8_t card_status, dma_status;
 725         unsigned long flags;
 726         irqreturn_t ret = IRQ_NONE;
 727
 728         spin_lock_irqsave(&dev->irqlock, flags);
 729
 730         /* handle card detection interrupts first */
 731         card_status = r852_read_reg(dev, R852_CARD_IRQ_STA);
 732         r852_write_reg(dev, R852_CARD_IRQ_STA, card_status);
 733
 734         if (card_status & (R852_CARD_IRQ_INSERT|R852_CARD_IRQ_REMOVE)) {
 735
 736                 ret = IRQ_HANDLED;
 737                 dev->card_detected = !!(card_status & R852_CARD_IRQ_INSERT);
 738
 739                 /* we shouldn't receive any interrupts if we wait for card
 740                         to settle */
 741                 WARN_ON(dev->card_unstable);
 742
 743                 /* disable irqs while card is unstable */
 744                 /* this will timeout DMA if active, but better that garbage */
 745                 r852_disable_irqs(dev);
 746
 747                 if (dev->card_unstable)
 748                         goto out;
 749
 750                 /* let, card state to settle a bit, and then do the work */
 751                 dev->card_unstable = 1;
 752                 queue_delayed_work(dev->card_workqueue,
 753                         &dev->card_detect_work, msecs_to_jiffies(100));
 754                 goto out;
 755         }
 756
 757
 758         /* Handle dma interrupts */
 759         dma_status = r852_read_reg_dword(dev, R852_DMA_IRQ_STA);
 760         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, dma_status);
 761
 762         if (dma_status & R852_DMA_IRQ_MASK) {
 763
 764                 ret = IRQ_HANDLED;
 765
 766                 if (dma_status & R852_DMA_IRQ_ERROR) {
 767                         dbg("received dma error IRQ");
 768                         r852_dma_done(dev, -EIO);
 769                         complete(&dev->dma_done);
 770                         goto out;
 771                 }
 772
 773                 /* received DMA interrupt out of nowhere? */
 774                 WARN_ON_ONCE(dev->dma_stage == 0);
 775
 776                 if (dev->dma_stage == 0)
 777                         goto out;
 778
 779                 /* done device access */
 780                 if (dev->dma_state == DMA_INTERNAL &&
 781                                 (dma_status & R852_DMA_IRQ_INTERNAL)) {
 782
 783                         dev->dma_state = DMA_MEMORY;
 784                         dev->dma_stage++;
 785                 }
 786
 787                 /* done memory DMA */
 788                 if (dev->dma_state == DMA_MEMORY &&
 789                                 (dma_status & R852_DMA_IRQ_MEMORY)) {
 790                         dev->dma_state = DMA_INTERNAL;
 791                         dev->dma_stage++;
 792                 }
 793
 794                 /* Enable 2nd half of dma dance */
 795                 if (dev->dma_stage == 2)
 796                         r852_dma_enable(dev);
 797
 798                 /* Operation done */
 799                 if (dev->dma_stage == 3) {
 800                         r852_dma_done(dev, 0);
 801                         complete(&dev->dma_done);
 802                 }
 803                 goto out;
 804         }
 805
 806         /* Handle unknown interrupts */
 807         if (dma_status)
 808                 dbg("bad dma IRQ status = %x", dma_status);
 809
 810         if (card_status & ~R852_CARD_STA_CD)
 811                 dbg("strange card status = %x", card_status);
 812
 813 out:
 814         spin_unlock_irqrestore(&dev->irqlock, flags);
 815         return ret;
 816 }
 817
 818 static int  r852_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
 819 {
 820         int error;
 821         struct nand_chip *chip;
 822         struct r852_device *dev;
 823
 824         /* pci initialization */
 825         error = pci_enable_device(pci_dev);
 826
 827         if (error)
 828                 goto error1;
 829
 830         pci_set_master(pci_dev);
 831
 832         error = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(32));
 833         if (error)
 834                 goto error2;
 835
 836         error = pci_request_regions(pci_dev, DRV_NAME);
 837
 838         if (error)
 839                 goto error3;
 840
 841         error = -ENOMEM;
 842
 843         /* init nand chip, but register it only on card insert */
 844         chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
 845
 846         if (!chip)
 847                 goto error4;
 848
 849         /* commands */
 850         chip->legacy.cmd_ctrl = r852_cmdctl;
 851         chip->legacy.waitfunc = r852_wait;
 852         chip->legacy.dev_ready = r852_ready;
 853
 854         /* I/O */
 855         chip->legacy.read_byte = r852_read_byte;
 856         chip->legacy.read_buf = r852_read_buf;
 857         chip->legacy.write_buf = r852_write_buf;
 858
 859         /* ecc */
 860         chip->ecc.mode = NAND_ECC_HW_SYNDROME;
 861         chip->ecc.size = R852_DMA_LEN;
 862         chip->ecc.bytes = SM_OOB_SIZE;
 863         chip->ecc.strength = 2;
 864         chip->ecc.hwctl = r852_ecc_hwctl;
 865         chip->ecc.calculate = r852_ecc_calculate;
 866         chip->ecc.correct = r852_ecc_correct;
 867
 868         /* TODO: hack */
 869         chip->ecc.read_oob = r852_read_oob;
 870
 871         /* init our device structure */
 872         dev = kzalloc(sizeof(struct r852_device), GFP_KERNEL);
 873
 874         if (!dev)
 875                 goto error5;
 876
 877         nand_set_controller_data(chip, dev);
 878         dev->chip = chip;
 879         dev->pci_dev = pci_dev;
 880         pci_set_drvdata(pci_dev, dev);
 881
 882         dev->bounce_buffer = dma_alloc_coherent(&pci_dev->dev, R852_DMA_LEN,
 883                 &dev->phys_bounce_buffer, GFP_KERNEL);
 884
 885         if (!dev->bounce_buffer)
 886                 goto error6;
 887
 888
 889         error = -ENODEV;
 890         dev->mmio = pci_ioremap_bar(pci_dev, 0);
 891
 892         if (!dev->mmio)
 893                 goto error7;
 894
 895         error = -ENOMEM;
 896         dev->tmp_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
 897
 898         if (!dev->tmp_buffer)
 899                 goto error8;
 900
 901         init_completion(&dev->dma_done);
 902
 903         dev->card_workqueue = create_freezable_workqueue(DRV_NAME);
 904
 905         if (!dev->card_workqueue)
 906                 goto error9;
 907
 908         INIT_DELAYED_WORK(&dev->card_detect_work, r852_card_detect_work);
 909
 910         /* shutdown everything - precation */
 911         r852_engine_disable(dev);
 912         r852_disable_irqs(dev);
 913
 914         r852_dma_test(dev);
 915
 916         dev->irq = pci_dev->irq;
 917         spin_lock_init(&dev->irqlock);
 918
 919         dev->card_detected = 0;
 920         r852_card_update_present(dev);
 921
 922         /*register irq handler*/
 923         error = -ENODEV;
 924         if (request_irq(pci_dev->irq, &r852_irq, IRQF_SHARED,
 925                           DRV_NAME, dev))
 926                 goto error10;
 927
 928         /* kick initial present test */
 929         queue_delayed_work(dev->card_workqueue,
 930                 &dev->card_detect_work, 0);
 931
 932
 933         pr_notice("driver loaded successfully\n");
 934         return 0;
 935
 936 error10:
 937         destroy_workqueue(dev->card_workqueue);
 938 error9:
 939         kfree(dev->tmp_buffer);
 940 error8:
 941         pci_iounmap(pci_dev, dev->mmio);
 942 error7:
 943         dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
 944                           dev->phys_bounce_buffer);
 945 error6:
 946         kfree(dev);
 947 error5:
 948         kfree(chip);
 949 error4:
 950         pci_release_regions(pci_dev);
 951 error3:
 952 error2:
 953         pci_disable_device(pci_dev);
 954 error1:
 955         return error;
 956 }
 957
 958 static void r852_remove(struct pci_dev *pci_dev)
 959 {
 960         struct r852_device *dev = pci_get_drvdata(pci_dev);
 961
 962         /* Stop detect workqueue -
 963                 we are going to unregister the device anyway*/
 964         cancel_delayed_work_sync(&dev->card_detect_work);
 965         destroy_workqueue(dev->card_workqueue);
 966
 967         /* Unregister the device, this might make more IO */
 968         r852_unregister_nand_device(dev);
 969
 970         /* Stop interrupts */
 971         r852_disable_irqs(dev);
 972         free_irq(dev->irq, dev);
 973
 974         /* Cleanup */
 975         kfree(dev->tmp_buffer);
 976         pci_iounmap(pci_dev, dev->mmio);
 977         dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
 978                           dev->phys_bounce_buffer);
 979
 980         kfree(dev->chip);
 981         kfree(dev);
 982
 983         /* Shutdown the PCI device */
 984         pci_release_regions(pci_dev);
 985         pci_disable_device(pci_dev);
 986 }
 987
 988 static void r852_shutdown(struct pci_dev *pci_dev)
 989 {
 990         struct r852_device *dev = pci_get_drvdata(pci_dev);
 991
 992         cancel_delayed_work_sync(&dev->card_detect_work);
 993         r852_disable_irqs(dev);
 994         synchronize_irq(dev->irq);
 995         pci_disable_device(pci_dev);
 996 }
 997
 998 #ifdef CONFIG_PM_SLEEP
 999 static int r852_suspend(struct device *device)
1000 {
1001         struct r852_device *dev = dev_get_drvdata(device);
1002
1003         if (dev->ctlreg & R852_CTL_CARDENABLE)
1004                 return -EBUSY;
1005
1006         /* First make sure the detect work is gone */
1007         cancel_delayed_work_sync(&dev->card_detect_work);
1008
1009         /* Turn off the interrupts and stop the device */
1010         r852_disable_irqs(dev);
1011         r852_engine_disable(dev);
1012
1013         /* If card was pulled off just during the suspend, which is very
1014                 unlikely, we will remove it on resume, it too late now
1015                 anyway... */
1016         dev->card_unstable = 0;
1017         return 0;
1018 }
1019
1020 static int r852_resume(struct device *device)
1021 {
1022         struct r852_device *dev = dev_get_drvdata(device);
1023
1024         r852_disable_irqs(dev);
1025         r852_card_update_present(dev);
1026         r852_engine_disable(dev);
1027
1028
1029         /* If card status changed, just do the work */
1030         if (dev->card_detected != dev->card_registered) {
1031                 dbg("card was %s during low power state",
1032                         dev->card_detected ? "added" : "removed");
1033
1034                 queue_delayed_work(dev->card_workqueue,
1035                 &dev->card_detect_work, msecs_to_jiffies(1000));
1036                 return 0;
1037         }
1038
1039         /* Otherwise, initialize the card */
1040         if (dev->card_registered) {
1041                 r852_engine_enable(dev);
1042                 nand_select_target(dev->chip, 0);
1043                 nand_reset_op(dev->chip);
1044                 nand_deselect_target(dev->chip);
1045         }
1046
1047         /* Program card detection IRQ */
1048         r852_update_card_detect(dev);
1049         return 0;
1050 }
1051 #endif
1052
1053 static const struct pci_device_id r852_pci_id_tbl[] = {
1054
1055         { PCI_VDEVICE(RICOH, 0x0852), },
1056         { },
1057 };
1058
1059 MODULE_DEVICE_TABLE(pci, r852_pci_id_tbl);
1060
1061 static SIMPLE_DEV_PM_OPS(r852_pm_ops, r852_suspend, r852_resume);
1062
1063 static struct pci_driver r852_pci_driver = {
1064         .name           = DRV_NAME,
1065         .id_table       = r852_pci_id_tbl,
1066         .probe          = r852_probe,
1067         .remove         = r852_remove,
1068         .shutdown       = r852_shutdown,
1069         .driver.pm      = &r852_pm_ops,
1070 };
1071
1072 module_pci_driver(r852_pci_driver);
1073
1074 MODULE_LICENSE("GPL");
1075 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1076 MODULE_DESCRIPTION("Ricoh 85xx xD/smartmedia card reader driver");