drivers/mtd/nand/raw/r852.c

   1 /*
   2  * Copyright © 2009 - Maxim Levitsky
   3  * driver for Ricoh xD readers
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 #define DRV_NAME "r852"
  11 #define pr_fmt(fmt)  DRV_NAME ": " fmt
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/jiffies.h>
  16 #include <linux/workqueue.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/pci.h>
  19 #include <linux/pci_ids.h>
  20 #include <linux/delay.h>
  21 #include <linux/slab.h>
  22 #include <asm/byteorder.h>
  23 #include <linux/sched.h>
  24 #include "sm_common.h"
  25 #include "r852.h"
  26
  27
  28 static bool r852_enable_dma = 1;
  29 module_param(r852_enable_dma, bool, S_IRUGO);
  30 MODULE_PARM_DESC(r852_enable_dma, "Enable usage of the DMA (default)");
  31
  32 static int debug;
  33 module_param(debug, int, S_IRUGO | S_IWUSR);
  34 MODULE_PARM_DESC(debug, "Debug level (0-2)");
  35
  36 /* read register */
  37 static inline uint8_t r852_read_reg(struct r852_device *dev, int address)
  38 {
  39         uint8_t reg = readb(dev->mmio + address);
  40         return reg;
  41 }
  42
  43 /* write register */
  44 static inline void r852_write_reg(struct r852_device *dev,
  45                                                 int address, uint8_t value)
  46 {
  47         writeb(value, dev->mmio + address);
  48         mmiowb();
  49 }
  50
  51
  52 /* read dword sized register */
  53 static inline uint32_t r852_read_reg_dword(struct r852_device *dev, int address)
  54 {
  55         uint32_t reg = le32_to_cpu(readl(dev->mmio + address));
  56         return reg;
  57 }
  58
  59 /* write dword sized register */
  60 static inline void r852_write_reg_dword(struct r852_device *dev,
  61                                                         int address, uint32_t value)
  62 {
  63         writel(cpu_to_le32(value), dev->mmio + address);
  64         mmiowb();
  65 }
  66
  67 /* returns pointer to our private structure */
  68 static inline struct r852_device *r852_get_dev(struct mtd_info *mtd)
  69 {
  70         struct nand_chip *chip = mtd_to_nand(mtd);
  71         return nand_get_controller_data(chip);
  72 }
  73
  74
  75 /* check if controller supports dma */
  76 static void r852_dma_test(struct r852_device *dev)
  77 {
  78         dev->dma_usable = (r852_read_reg(dev, R852_DMA_CAP) &
  79                 (R852_DMA1 | R852_DMA2)) == (R852_DMA1 | R852_DMA2);
  80
  81         if (!dev->dma_usable)
  82                 message("Non dma capable device detected, dma disabled");
  83
  84         if (!r852_enable_dma) {
  85                 message("disabling dma on user request");
  86                 dev->dma_usable = 0;
  87         }
  88 }
  89
  90 /*
  91  * Enable dma. Enables ether first or second stage of the DMA,
  92  * Expects dev->dma_dir and dev->dma_state be set
  93  */
  94 static void r852_dma_enable(struct r852_device *dev)
  95 {
  96         uint8_t dma_reg, dma_irq_reg;
  97
  98         /* Set up dma settings */
  99         dma_reg = r852_read_reg_dword(dev, R852_DMA_SETTINGS);
 100         dma_reg &= ~(R852_DMA_READ | R852_DMA_INTERNAL | R852_DMA_MEMORY);
 101
 102         if (dev->dma_dir)
 103                 dma_reg |= R852_DMA_READ;
 104
 105         if (dev->dma_state == DMA_INTERNAL) {
 106                 dma_reg |= R852_DMA_INTERNAL;
 107                 /* Precaution to make sure HW doesn't write */
 108                         /* to random kernel memory */
 109                 r852_write_reg_dword(dev, R852_DMA_ADDR,
 110                         cpu_to_le32(dev->phys_bounce_buffer));
 111         } else {
 112                 dma_reg |= R852_DMA_MEMORY;
 113                 r852_write_reg_dword(dev, R852_DMA_ADDR,
 114                         cpu_to_le32(dev->phys_dma_addr));
 115         }
 116
 117         /* Precaution: make sure write reached the device */
 118         r852_read_reg_dword(dev, R852_DMA_ADDR);
 119
 120         r852_write_reg_dword(dev, R852_DMA_SETTINGS, dma_reg);
 121
 122         /* Set dma irq */
 123         dma_irq_reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
 124         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
 125                 dma_irq_reg |
 126                 R852_DMA_IRQ_INTERNAL |
 127                 R852_DMA_IRQ_ERROR |
 128                 R852_DMA_IRQ_MEMORY);
 129 }
 130
 131 /*
 132  * Disable dma, called from the interrupt handler, which specifies
 133  * success of the operation via 'error' argument
 134  */
 135 static void r852_dma_done(struct r852_device *dev, int error)
 136 {
 137         WARN_ON(dev->dma_stage == 0);
 138
 139         r852_write_reg_dword(dev, R852_DMA_IRQ_STA,
 140                         r852_read_reg_dword(dev, R852_DMA_IRQ_STA));
 141
 142         r852_write_reg_dword(dev, R852_DMA_SETTINGS, 0);
 143         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE, 0);
 144
 145         /* Precaution to make sure HW doesn't write to random kernel memory */
 146         r852_write_reg_dword(dev, R852_DMA_ADDR,
 147                 cpu_to_le32(dev->phys_bounce_buffer));
 148         r852_read_reg_dword(dev, R852_DMA_ADDR);
 149
 150         dev->dma_error = error;
 151         dev->dma_stage = 0;
 152
 153         if (dev->phys_dma_addr && dev->phys_dma_addr != dev->phys_bounce_buffer)
 154                 dma_unmap_single(&dev->pci_dev->dev, dev->phys_dma_addr,
 155                         R852_DMA_LEN,
 156                         dev->dma_dir ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
 157 }
 158
 159 /*
 160  * Wait, till dma is done, which includes both phases of it
 161  */
 162 static int r852_dma_wait(struct r852_device *dev)
 163 {
 164         long timeout = wait_for_completion_timeout(&dev->dma_done,
 165                                 msecs_to_jiffies(1000));
 166         if (!timeout) {
 167                 dbg("timeout waiting for DMA interrupt");
 168                 return -ETIMEDOUT;
 169         }
 170
 171         return 0;
 172 }
 173
 174 /*
 175  * Read/Write one page using dma. Only pages can be read (512 bytes)
 176 */
 177 static void r852_do_dma(struct r852_device *dev, uint8_t *buf, int do_read)
 178 {
 179         int bounce = 0;
 180         unsigned long flags;
 181         int error;
 182
 183         dev->dma_error = 0;
 184
 185         /* Set dma direction */
 186         dev->dma_dir = do_read;
 187         dev->dma_stage = 1;
 188         reinit_completion(&dev->dma_done);
 189
 190         dbg_verbose("doing dma %s ", do_read ? "read" : "write");
 191
 192         /* Set initial dma state: for reading first fill on board buffer,
 193           from device, for writes first fill the buffer  from memory*/
 194         dev->dma_state = do_read ? DMA_INTERNAL : DMA_MEMORY;
 195
 196         /* if incoming buffer is not page aligned, we should do bounce */
 197         if ((unsigned long)buf & (R852_DMA_LEN-1))
 198                 bounce = 1;
 199
 200         if (!bounce) {
 201                 dev->phys_dma_addr = dma_map_single(&dev->pci_dev->dev, buf,
 202                         R852_DMA_LEN,
 203                         do_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
 204                 if (dma_mapping_error(&dev->pci_dev->dev, dev->phys_dma_addr))
 205                         bounce = 1;
 206         }
 207
 208         if (bounce) {
 209                 dbg_verbose("dma: using bounce buffer");
 210                 dev->phys_dma_addr = dev->phys_bounce_buffer;
 211                 if (!do_read)
 212                         memcpy(dev->bounce_buffer, buf, R852_DMA_LEN);
 213         }
 214
 215         /* Enable DMA */
 216         spin_lock_irqsave(&dev->irqlock, flags);
 217         r852_dma_enable(dev);
 218         spin_unlock_irqrestore(&dev->irqlock, flags);
 219
 220         /* Wait till complete */
 221         error = r852_dma_wait(dev);
 222
 223         if (error) {
 224                 r852_dma_done(dev, error);
 225                 return;
 226         }
 227
 228         if (do_read && bounce)
 229                 memcpy((void *)buf, dev->bounce_buffer, R852_DMA_LEN);
 230 }
 231
 232 /*
 233  * Program data lines of the nand chip to send data to it
 234  */
 235 static void r852_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
 236 {
 237         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 238         uint32_t reg;
 239
 240         /* Don't allow any access to hardware if we suspect card removal */
 241         if (dev->card_unstable)
 242                 return;
 243
 244         /* Special case for whole sector read */
 245         if (len == R852_DMA_LEN && dev->dma_usable) {
 246                 r852_do_dma(dev, (uint8_t *)buf, 0);
 247                 return;
 248         }
 249
 250         /* write DWORD chinks - faster */
 251         while (len >= 4) {
 252                 reg = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24;
 253                 r852_write_reg_dword(dev, R852_DATALINE, reg);
 254                 buf += 4;
 255                 len -= 4;
 256
 257         }
 258
 259         /* write rest */
 260         while (len > 0) {
 261                 r852_write_reg(dev, R852_DATALINE, *buf++);
 262                 len--;
 263         }
 264 }
 265
 266 /*
 267  * Read data lines of the nand chip to retrieve data
 268  */
 269 static void r852_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
 270 {
 271         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 272         uint32_t reg;
 273
 274         if (dev->card_unstable) {
 275                 /* since we can't signal error here, at least, return
 276                         predictable buffer */
 277                 memset(buf, 0, len);
 278                 return;
 279         }
 280
 281         /* special case for whole sector read */
 282         if (len == R852_DMA_LEN && dev->dma_usable) {
 283                 r852_do_dma(dev, buf, 1);
 284                 return;
 285         }
 286
 287         /* read in dword sized chunks */
 288         while (len >= 4) {
 289
 290                 reg = r852_read_reg_dword(dev, R852_DATALINE);
 291                 *buf++ = reg & 0xFF;
 292                 *buf++ = (reg >> 8) & 0xFF;
 293                 *buf++ = (reg >> 16) & 0xFF;
 294                 *buf++ = (reg >> 24) & 0xFF;
 295                 len -= 4;
 296         }
 297
 298         /* read the reset by bytes */
 299         while (len--)
 300                 *buf++ = r852_read_reg(dev, R852_DATALINE);
 301 }
 302
 303 /*
 304  * Read one byte from nand chip
 305  */
 306 static uint8_t r852_read_byte(struct nand_chip *chip)
 307 {
 308         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 309
 310         /* Same problem as in r852_read_buf.... */
 311         if (dev->card_unstable)
 312                 return 0;
 313
 314         return r852_read_reg(dev, R852_DATALINE);
 315 }
 316
 317 /*
 318  * Control several chip lines & send commands
 319  */
 320 static void r852_cmdctl(struct nand_chip *chip, int dat, unsigned int ctrl)
 321 {
 322         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 323
 324         if (dev->card_unstable)
 325                 return;
 326
 327         if (ctrl & NAND_CTRL_CHANGE) {
 328
 329                 dev->ctlreg &= ~(R852_CTL_DATA | R852_CTL_COMMAND |
 330                                  R852_CTL_ON | R852_CTL_CARDENABLE);
 331
 332                 if (ctrl & NAND_ALE)
 333                         dev->ctlreg |= R852_CTL_DATA;
 334
 335                 if (ctrl & NAND_CLE)
 336                         dev->ctlreg |= R852_CTL_COMMAND;
 337
 338                 if (ctrl & NAND_NCE)
 339                         dev->ctlreg |= (R852_CTL_CARDENABLE | R852_CTL_ON);
 340                 else
 341                         dev->ctlreg &= ~R852_CTL_WRITE;
 342
 343                 /* when write is stareted, enable write access */
 344                 if (dat == NAND_CMD_ERASE1)
 345                         dev->ctlreg |= R852_CTL_WRITE;
 346
 347                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 348         }
 349
 350          /* HACK: NAND_CMD_SEQIN is called without NAND_CTRL_CHANGE, but we need
 351                 to set write mode */
 352         if (dat == NAND_CMD_SEQIN && (dev->ctlreg & R852_CTL_COMMAND)) {
 353                 dev->ctlreg |= R852_CTL_WRITE;
 354                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 355         }
 356
 357         if (dat != NAND_CMD_NONE)
 358                 r852_write_reg(dev, R852_DATALINE, dat);
 359 }
 360
 361 /*
 362  * Wait till card is ready.
 363  * based on nand_wait, but returns errors on DMA error
 364  */
 365 static int r852_wait(struct nand_chip *chip)
 366 {
 367         struct r852_device *dev = nand_get_controller_data(chip);
 368
 369         unsigned long timeout;
 370         u8 status;
 371
 372         timeout = jiffies + msecs_to_jiffies(400);
 373
 374         while (time_before(jiffies, timeout))
 375                 if (chip->legacy.dev_ready(chip))
 376                         break;
 377
 378         nand_status_op(chip, &status);
 379
 380         /* Unfortunelly, no way to send detailed error status... */
 381         if (dev->dma_error) {
 382                 status |= NAND_STATUS_FAIL;
 383                 dev->dma_error = 0;
 384         }
 385         return status;
 386 }
 387
 388 /*
 389  * Check if card is ready
 390  */
 391
 392 static int r852_ready(struct nand_chip *chip)
 393 {
 394         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 395         return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY);
 396 }
 397
 398
 399 /*
 400  * Set ECC engine mode
 401 */
 402
 403 static void r852_ecc_hwctl(struct nand_chip *chip, int mode)
 404 {
 405         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 406
 407         if (dev->card_unstable)
 408                 return;
 409
 410         switch (mode) {
 411         case NAND_ECC_READ:
 412         case NAND_ECC_WRITE:
 413                 /* enable ecc generation/check*/
 414                 dev->ctlreg |= R852_CTL_ECC_ENABLE;
 415
 416                 /* flush ecc buffer */
 417                 r852_write_reg(dev, R852_CTL,
 418                         dev->ctlreg | R852_CTL_ECC_ACCESS);
 419
 420                 r852_read_reg_dword(dev, R852_DATALINE);
 421                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 422                 return;
 423
 424         case NAND_ECC_READSYN:
 425                 /* disable ecc generation */
 426                 dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
 427                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
 428         }
 429 }
 430
 431 /*
 432  * Calculate ECC, only used for writes
 433  */
 434
 435 static int r852_ecc_calculate(struct nand_chip *chip, const uint8_t *dat,
 436                               uint8_t *ecc_code)
 437 {
 438         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 439         struct sm_oob *oob = (struct sm_oob *)ecc_code;
 440         uint32_t ecc1, ecc2;
 441
 442         if (dev->card_unstable)
 443                 return 0;
 444
 445         dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
 446         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
 447
 448         ecc1 = r852_read_reg_dword(dev, R852_DATALINE);
 449         ecc2 = r852_read_reg_dword(dev, R852_DATALINE);
 450
 451         oob->ecc1[0] = (ecc1) & 0xFF;
 452         oob->ecc1[1] = (ecc1 >> 8) & 0xFF;
 453         oob->ecc1[2] = (ecc1 >> 16) & 0xFF;
 454
 455         oob->ecc2[0] = (ecc2) & 0xFF;
 456         oob->ecc2[1] = (ecc2 >> 8) & 0xFF;
 457         oob->ecc2[2] = (ecc2 >> 16) & 0xFF;
 458
 459         r852_write_reg(dev, R852_CTL, dev->ctlreg);
 460         return 0;
 461 }
 462
 463 /*
 464  * Correct the data using ECC, hw did almost everything for us
 465  */
 466
 467 static int r852_ecc_correct(struct nand_chip *chip, uint8_t *dat,
 468                             uint8_t *read_ecc, uint8_t *calc_ecc)
 469 {
 470         uint32_t ecc_reg;
 471         uint8_t ecc_status, err_byte;
 472         int i, error = 0;
 473
 474         struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
 475
 476         if (dev->card_unstable)
 477                 return 0;
 478
 479         if (dev->dma_error) {
 480                 dev->dma_error = 0;
 481                 return -EIO;
 482         }
 483
 484         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
 485         ecc_reg = r852_read_reg_dword(dev, R852_DATALINE);
 486         r852_write_reg(dev, R852_CTL, dev->ctlreg);
 487
 488         for (i = 0 ; i <= 1 ; i++) {
 489
 490                 ecc_status = (ecc_reg >> 8) & 0xFF;
 491
 492                 /* ecc uncorrectable error */
 493                 if (ecc_status & R852_ECC_FAIL) {
 494                         dbg("ecc: unrecoverable error, in half %d", i);
 495                         error = -EBADMSG;
 496                         goto exit;
 497                 }
 498
 499                 /* correctable error */
 500                 if (ecc_status & R852_ECC_CORRECTABLE) {
 501
 502                         err_byte = ecc_reg & 0xFF;
 503                         dbg("ecc: recoverable error, "
 504                                 "in half %d, byte %d, bit %d", i,
 505                                 err_byte, ecc_status & R852_ECC_ERR_BIT_MSK);
 506
 507                         dat[err_byte] ^=
 508                                 1 << (ecc_status & R852_ECC_ERR_BIT_MSK);
 509                         error++;
 510                 }
 511
 512                 dat += 256;
 513                 ecc_reg >>= 16;
 514         }
 515 exit:
 516         return error;
 517 }
 518
 519 /*
 520  * This is copy of nand_read_oob_std
 521  * nand_read_oob_syndrome assumes we can send column address - we can't
 522  */
 523 static int r852_read_oob(struct nand_chip *chip, int page)
 524 {
 525         struct mtd_info *mtd = nand_to_mtd(chip);
 526
 527         return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
 528 }
 529
 530 /*
 531  * Start the nand engine
 532  */
 533
 534 static void r852_engine_enable(struct r852_device *dev)
 535 {
 536         if (r852_read_reg_dword(dev, R852_HW) & R852_HW_UNKNOWN) {
 537                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
 538                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
 539         } else {
 540                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
 541                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
 542         }
 543         msleep(300);
 544         r852_write_reg(dev, R852_CTL, 0);
 545 }
 546
 547
 548 /*
 549  * Stop the nand engine
 550  */
 551
 552 static void r852_engine_disable(struct r852_device *dev)
 553 {
 554         r852_write_reg_dword(dev, R852_HW, 0);
 555         r852_write_reg(dev, R852_CTL, R852_CTL_RESET);
 556 }
 557
 558 /*
 559  * Test if card is present
 560  */
 561
 562 static void r852_card_update_present(struct r852_device *dev)
 563 {
 564         unsigned long flags;
 565         uint8_t reg;
 566
 567         spin_lock_irqsave(&dev->irqlock, flags);
 568         reg = r852_read_reg(dev, R852_CARD_STA);
 569         dev->card_detected = !!(reg & R852_CARD_STA_PRESENT);
 570         spin_unlock_irqrestore(&dev->irqlock, flags);
 571 }
 572
 573 /*
 574  * Update card detection IRQ state according to current card state
 575  * which is read in r852_card_update_present
 576  */
 577 static void r852_update_card_detect(struct r852_device *dev)
 578 {
 579         int card_detect_reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
 580         dev->card_unstable = 0;
 581
 582         card_detect_reg &= ~(R852_CARD_IRQ_REMOVE | R852_CARD_IRQ_INSERT);
 583         card_detect_reg |= R852_CARD_IRQ_GENABLE;
 584
 585         card_detect_reg |= dev->card_detected ?
 586                 R852_CARD_IRQ_REMOVE : R852_CARD_IRQ_INSERT;
 587
 588         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, card_detect_reg);
 589 }
 590
 591 static ssize_t r852_media_type_show(struct device *sys_dev,
 592                         struct device_attribute *attr, char *buf)
 593 {
 594         struct mtd_info *mtd = container_of(sys_dev, struct mtd_info, dev);
 595         struct r852_device *dev = r852_get_dev(mtd);
 596         char *data = dev->sm ? "smartmedia" : "xd";
 597
 598         strcpy(buf, data);
 599         return strlen(data);
 600 }
 601
 602 static DEVICE_ATTR(media_type, S_IRUGO, r852_media_type_show, NULL);
 603
 604
 605 /* Detect properties of card in slot */
 606 static void r852_update_media_status(struct r852_device *dev)
 607 {
 608         uint8_t reg;
 609         unsigned long flags;
 610         int readonly;
 611
 612         spin_lock_irqsave(&dev->irqlock, flags);
 613         if (!dev->card_detected) {
 614                 message("card removed");
 615                 spin_unlock_irqrestore(&dev->irqlock, flags);
 616                 return ;
 617         }
 618
 619         readonly  = r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_RO;
 620         reg = r852_read_reg(dev, R852_DMA_CAP);
 621         dev->sm = (reg & (R852_DMA1 | R852_DMA2)) && (reg & R852_SMBIT);
 622
 623         message("detected %s %s card in slot",
 624                 dev->sm ? "SmartMedia" : "xD",
 625                 readonly ? "readonly" : "writeable");
 626
 627         dev->readonly = readonly;
 628         spin_unlock_irqrestore(&dev->irqlock, flags);
 629 }
 630
 631 /*
 632  * Register the nand device
 633  * Called when the card is detected
 634  */
 635 static int r852_register_nand_device(struct r852_device *dev)
 636 {
 637         struct mtd_info *mtd = nand_to_mtd(dev->chip);
 638
 639         WARN_ON(dev->card_registered);
 640
 641         mtd->dev.parent = &dev->pci_dev->dev;
 642
 643         if (dev->readonly)
 644                 dev->chip->options |= NAND_ROM;
 645
 646         r852_engine_enable(dev);
 647
 648         if (sm_register_device(mtd, dev->sm))
 649                 goto error1;
 650
 651         if (device_create_file(&mtd->dev, &dev_attr_media_type)) {
 652                 message("can't create media type sysfs attribute");
 653                 goto error3;
 654         }
 655
 656         dev->card_registered = 1;
 657         return 0;
 658 error3:
 659         nand_release(dev->chip);
 660 error1:
 661         /* Force card redetect */
 662         dev->card_detected = 0;
 663         return -1;
 664 }
 665
 666 /*
 667  * Unregister the card
 668  */
 669
 670 static void r852_unregister_nand_device(struct r852_device *dev)
 671 {
 672         struct mtd_info *mtd = nand_to_mtd(dev->chip);
 673
 674         if (!dev->card_registered)
 675                 return;
 676
 677         device_remove_file(&mtd->dev, &dev_attr_media_type);
 678         nand_release(dev->chip);
 679         r852_engine_disable(dev);
 680         dev->card_registered = 0;
 681 }
 682
 683 /* Card state updater */
 684 static void r852_card_detect_work(struct work_struct *work)
 685 {
 686         struct r852_device *dev =
 687                 container_of(work, struct r852_device, card_detect_work.work);
 688
 689         r852_card_update_present(dev);
 690         r852_update_card_detect(dev);
 691         dev->card_unstable = 0;
 692
 693         /* False alarm */
 694         if (dev->card_detected == dev->card_registered)
 695                 goto exit;
 696
 697         /* Read media properties */
 698         r852_update_media_status(dev);
 699
 700         /* Register the card */
 701         if (dev->card_detected)
 702                 r852_register_nand_device(dev);
 703         else
 704                 r852_unregister_nand_device(dev);
 705 exit:
 706         r852_update_card_detect(dev);
 707 }
 708
 709 /* Ack + disable IRQ generation */
 710 static void r852_disable_irqs(struct r852_device *dev)
 711 {
 712         uint8_t reg;
 713         reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
 714         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, reg & ~R852_CARD_IRQ_MASK);
 715
 716         reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
 717         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
 718                                         reg & ~R852_DMA_IRQ_MASK);
 719
 720         r852_write_reg(dev, R852_CARD_IRQ_STA, R852_CARD_IRQ_MASK);
 721         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, R852_DMA_IRQ_MASK);
 722 }
 723
 724 /* Interrupt handler */
 725 static irqreturn_t r852_irq(int irq, void *data)
 726 {
 727         struct r852_device *dev = (struct r852_device *)data;
 728
 729         uint8_t card_status, dma_status;
 730         unsigned long flags;
 731         irqreturn_t ret = IRQ_NONE;
 732
 733         spin_lock_irqsave(&dev->irqlock, flags);
 734
 735         /* handle card detection interrupts first */
 736         card_status = r852_read_reg(dev, R852_CARD_IRQ_STA);
 737         r852_write_reg(dev, R852_CARD_IRQ_STA, card_status);
 738
 739         if (card_status & (R852_CARD_IRQ_INSERT|R852_CARD_IRQ_REMOVE)) {
 740
 741                 ret = IRQ_HANDLED;
 742                 dev->card_detected = !!(card_status & R852_CARD_IRQ_INSERT);
 743
 744                 /* we shouldn't receive any interrupts if we wait for card
 745                         to settle */
 746                 WARN_ON(dev->card_unstable);
 747
 748                 /* disable irqs while card is unstable */
 749                 /* this will timeout DMA if active, but better that garbage */
 750                 r852_disable_irqs(dev);
 751
 752                 if (dev->card_unstable)
 753                         goto out;
 754
 755                 /* let, card state to settle a bit, and then do the work */
 756                 dev->card_unstable = 1;
 757                 queue_delayed_work(dev->card_workqueue,
 758                         &dev->card_detect_work, msecs_to_jiffies(100));
 759                 goto out;
 760         }
 761
 762
 763         /* Handle dma interrupts */
 764         dma_status = r852_read_reg_dword(dev, R852_DMA_IRQ_STA);
 765         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, dma_status);
 766
 767         if (dma_status & R852_DMA_IRQ_MASK) {
 768
 769                 ret = IRQ_HANDLED;
 770
 771                 if (dma_status & R852_DMA_IRQ_ERROR) {
 772                         dbg("received dma error IRQ");
 773                         r852_dma_done(dev, -EIO);
 774                         complete(&dev->dma_done);
 775                         goto out;
 776                 }
 777
 778                 /* received DMA interrupt out of nowhere? */
 779                 WARN_ON_ONCE(dev->dma_stage == 0);
 780
 781                 if (dev->dma_stage == 0)
 782                         goto out;
 783
 784                 /* done device access */
 785                 if (dev->dma_state == DMA_INTERNAL &&
 786                                 (dma_status & R852_DMA_IRQ_INTERNAL)) {
 787
 788                         dev->dma_state = DMA_MEMORY;
 789                         dev->dma_stage++;
 790                 }
 791
 792                 /* done memory DMA */
 793                 if (dev->dma_state == DMA_MEMORY &&
 794                                 (dma_status & R852_DMA_IRQ_MEMORY)) {
 795                         dev->dma_state = DMA_INTERNAL;
 796                         dev->dma_stage++;
 797                 }
 798
 799                 /* Enable 2nd half of dma dance */
 800                 if (dev->dma_stage == 2)
 801                         r852_dma_enable(dev);
 802
 803                 /* Operation done */
 804                 if (dev->dma_stage == 3) {
 805                         r852_dma_done(dev, 0);
 806                         complete(&dev->dma_done);
 807                 }
 808                 goto out;
 809         }
 810
 811         /* Handle unknown interrupts */
 812         if (dma_status)
 813                 dbg("bad dma IRQ status = %x", dma_status);
 814
 815         if (card_status & ~R852_CARD_STA_CD)
 816                 dbg("strange card status = %x", card_status);
 817
 818 out:
 819         spin_unlock_irqrestore(&dev->irqlock, flags);
 820         return ret;
 821 }
 822
 823 static int  r852_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
 824 {
 825         int error;
 826         struct nand_chip *chip;
 827         struct r852_device *dev;
 828
 829         /* pci initialization */
 830         error = pci_enable_device(pci_dev);
 831
 832         if (error)
 833                 goto error1;
 834
 835         pci_set_master(pci_dev);
 836
 837         error = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(32));
 838         if (error)
 839                 goto error2;
 840
 841         error = pci_request_regions(pci_dev, DRV_NAME);
 842
 843         if (error)
 844                 goto error3;
 845
 846         error = -ENOMEM;
 847
 848         /* init nand chip, but register it only on card insert */
 849         chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
 850
 851         if (!chip)
 852                 goto error4;
 853
 854         /* commands */
 855         chip->legacy.cmd_ctrl = r852_cmdctl;
 856         chip->legacy.waitfunc = r852_wait;
 857         chip->legacy.dev_ready = r852_ready;
 858
 859         /* I/O */
 860         chip->legacy.read_byte = r852_read_byte;
 861         chip->legacy.read_buf = r852_read_buf;
 862         chip->legacy.write_buf = r852_write_buf;
 863
 864         /* ecc */
 865         chip->ecc.mode = NAND_ECC_HW_SYNDROME;
 866         chip->ecc.size = R852_DMA_LEN;
 867         chip->ecc.bytes = SM_OOB_SIZE;
 868         chip->ecc.strength = 2;
 869         chip->ecc.hwctl = r852_ecc_hwctl;
 870         chip->ecc.calculate = r852_ecc_calculate;
 871         chip->ecc.correct = r852_ecc_correct;
 872
 873         /* TODO: hack */
 874         chip->ecc.read_oob = r852_read_oob;
 875
 876         /* init our device structure */
 877         dev = kzalloc(sizeof(struct r852_device), GFP_KERNEL);
 878
 879         if (!dev)
 880                 goto error5;
 881
 882         nand_set_controller_data(chip, dev);
 883         dev->chip = chip;
 884         dev->pci_dev = pci_dev;
 885         pci_set_drvdata(pci_dev, dev);
 886
 887         dev->bounce_buffer = dma_alloc_coherent(&pci_dev->dev, R852_DMA_LEN,
 888                 &dev->phys_bounce_buffer, GFP_KERNEL);
 889
 890         if (!dev->bounce_buffer)
 891                 goto error6;
 892
 893
 894         error = -ENODEV;
 895         dev->mmio = pci_ioremap_bar(pci_dev, 0);
 896
 897         if (!dev->mmio)
 898                 goto error7;
 899
 900         error = -ENOMEM;
 901         dev->tmp_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
 902
 903         if (!dev->tmp_buffer)
 904                 goto error8;
 905
 906         init_completion(&dev->dma_done);
 907
 908         dev->card_workqueue = create_freezable_workqueue(DRV_NAME);
 909
 910         if (!dev->card_workqueue)
 911                 goto error9;
 912
 913         INIT_DELAYED_WORK(&dev->card_detect_work, r852_card_detect_work);
 914
 915         /* shutdown everything - precation */
 916         r852_engine_disable(dev);
 917         r852_disable_irqs(dev);
 918
 919         r852_dma_test(dev);
 920
 921         dev->irq = pci_dev->irq;
 922         spin_lock_init(&dev->irqlock);
 923
 924         dev->card_detected = 0;
 925         r852_card_update_present(dev);
 926
 927         /*register irq handler*/
 928         error = -ENODEV;
 929         if (request_irq(pci_dev->irq, &r852_irq, IRQF_SHARED,
 930                           DRV_NAME, dev))
 931                 goto error10;
 932
 933         /* kick initial present test */
 934         queue_delayed_work(dev->card_workqueue,
 935                 &dev->card_detect_work, 0);
 936
 937
 938         pr_notice("driver loaded successfully\n");
 939         return 0;
 940
 941 error10:
 942         destroy_workqueue(dev->card_workqueue);
 943 error9:
 944         kfree(dev->tmp_buffer);
 945 error8:
 946         pci_iounmap(pci_dev, dev->mmio);
 947 error7:
 948         dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
 949                           dev->phys_bounce_buffer);
 950 error6:
 951         kfree(dev);
 952 error5:
 953         kfree(chip);
 954 error4:
 955         pci_release_regions(pci_dev);
 956 error3:
 957 error2:
 958         pci_disable_device(pci_dev);
 959 error1:
 960         return error;
 961 }
 962
 963 static void r852_remove(struct pci_dev *pci_dev)
 964 {
 965         struct r852_device *dev = pci_get_drvdata(pci_dev);
 966
 967         /* Stop detect workqueue -
 968                 we are going to unregister the device anyway*/
 969         cancel_delayed_work_sync(&dev->card_detect_work);
 970         destroy_workqueue(dev->card_workqueue);
 971
 972         /* Unregister the device, this might make more IO */
 973         r852_unregister_nand_device(dev);
 974
 975         /* Stop interrupts */
 976         r852_disable_irqs(dev);
 977         free_irq(dev->irq, dev);
 978
 979         /* Cleanup */
 980         kfree(dev->tmp_buffer);
 981         pci_iounmap(pci_dev, dev->mmio);
 982         dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
 983                           dev->phys_bounce_buffer);
 984
 985         kfree(dev->chip);
 986         kfree(dev);
 987
 988         /* Shutdown the PCI device */
 989         pci_release_regions(pci_dev);
 990         pci_disable_device(pci_dev);
 991 }
 992
 993 static void r852_shutdown(struct pci_dev *pci_dev)
 994 {
 995         struct r852_device *dev = pci_get_drvdata(pci_dev);
 996
 997         cancel_delayed_work_sync(&dev->card_detect_work);
 998         r852_disable_irqs(dev);
 999         synchronize_irq(dev->irq);
1000         pci_disable_device(pci_dev);
1001 }
1002
1003 #ifdef CONFIG_PM_SLEEP
1004 static int r852_suspend(struct device *device)
1005 {
1006         struct r852_device *dev = pci_get_drvdata(to_pci_dev(device));
1007
1008         if (dev->ctlreg & R852_CTL_CARDENABLE)
1009                 return -EBUSY;
1010
1011         /* First make sure the detect work is gone */
1012         cancel_delayed_work_sync(&dev->card_detect_work);
1013
1014         /* Turn off the interrupts and stop the device */
1015         r852_disable_irqs(dev);
1016         r852_engine_disable(dev);
1017
1018         /* If card was pulled off just during the suspend, which is very
1019                 unlikely, we will remove it on resume, it too late now
1020                 anyway... */
1021         dev->card_unstable = 0;
1022         return 0;
1023 }
1024
1025 static int r852_resume(struct device *device)
1026 {
1027         struct r852_device *dev = pci_get_drvdata(to_pci_dev(device));
1028
1029         r852_disable_irqs(dev);
1030         r852_card_update_present(dev);
1031         r852_engine_disable(dev);
1032
1033
1034         /* If card status changed, just do the work */
1035         if (dev->card_detected != dev->card_registered) {
1036                 dbg("card was %s during low power state",
1037                         dev->card_detected ? "added" : "removed");
1038
1039                 queue_delayed_work(dev->card_workqueue,
1040                 &dev->card_detect_work, msecs_to_jiffies(1000));
1041                 return 0;
1042         }
1043
1044         /* Otherwise, initialize the card */
1045         if (dev->card_registered) {
1046                 r852_engine_enable(dev);
1047                 nand_select_target(dev->chip, 0);
1048                 nand_reset_op(dev->chip);
1049                 nand_deselect_target(dev->chip);
1050         }
1051
1052         /* Program card detection IRQ */
1053         r852_update_card_detect(dev);
1054         return 0;
1055 }
1056 #endif
1057
1058 static const struct pci_device_id r852_pci_id_tbl[] = {
1059
1060         { PCI_VDEVICE(RICOH, 0x0852), },
1061         { },
1062 };
1063
1064 MODULE_DEVICE_TABLE(pci, r852_pci_id_tbl);
1065
1066 static SIMPLE_DEV_PM_OPS(r852_pm_ops, r852_suspend, r852_resume);
1067
1068 static struct pci_driver r852_pci_driver = {
1069         .name           = DRV_NAME,
1070         .id_table       = r852_pci_id_tbl,
1071         .probe          = r852_probe,
1072         .remove         = r852_remove,
1073         .shutdown       = r852_shutdown,
1074         .driver.pm      = &r852_pm_ops,
1075 };
1076
1077 module_pci_driver(r852_pci_driver);
1078
1079 MODULE_LICENSE("GPL");
1080 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1081 MODULE_DESCRIPTION("Ricoh 85xx xD/smartmedia card reader driver");