Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / mtd / nand / r852.c
diff --git a/kernel/drivers/mtd/nand/r852.c b/kernel/drivers/mtd/nand/r852.c
new file mode 100644 (file)
index 0000000..baea83f
--- /dev/null
@@ -0,0 +1,1085 @@
+/*
+ * Copyright © 2009 - Maxim Levitsky
+ * driver for Ricoh xD readers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <asm/byteorder.h>
+#include <linux/sched.h>
+#include "sm_common.h"
+#include "r852.h"
+
+
+static bool r852_enable_dma = 1;
+module_param(r852_enable_dma, bool, S_IRUGO);
+MODULE_PARM_DESC(r852_enable_dma, "Enable usage of the DMA (default)");
+
+static int debug;
+module_param(debug, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Debug level (0-2)");
+
+/* read register */
+static inline uint8_t r852_read_reg(struct r852_device *dev, int address)
+{
+       uint8_t reg = readb(dev->mmio + address);
+       return reg;
+}
+
+/* write register */
+static inline void r852_write_reg(struct r852_device *dev,
+                                               int address, uint8_t value)
+{
+       writeb(value, dev->mmio + address);
+       mmiowb();
+}
+
+
+/* read dword sized register */
+static inline uint32_t r852_read_reg_dword(struct r852_device *dev, int address)
+{
+       uint32_t reg = le32_to_cpu(readl(dev->mmio + address));
+       return reg;
+}
+
+/* write dword sized register */
+static inline void r852_write_reg_dword(struct r852_device *dev,
+                                                       int address, uint32_t value)
+{
+       writel(cpu_to_le32(value), dev->mmio + address);
+       mmiowb();
+}
+
+/* returns pointer to our private structure */
+static inline struct r852_device *r852_get_dev(struct mtd_info *mtd)
+{
+       struct nand_chip *chip = mtd->priv;
+       return chip->priv;
+}
+
+
+/* check if controller supports dma */
+static void r852_dma_test(struct r852_device *dev)
+{
+       dev->dma_usable = (r852_read_reg(dev, R852_DMA_CAP) &
+               (R852_DMA1 | R852_DMA2)) == (R852_DMA1 | R852_DMA2);
+
+       if (!dev->dma_usable)
+               message("Non dma capable device detected, dma disabled");
+
+       if (!r852_enable_dma) {
+               message("disabling dma on user request");
+               dev->dma_usable = 0;
+       }
+}
+
+/*
+ * Enable dma. Enables ether first or second stage of the DMA,
+ * Expects dev->dma_dir and dev->dma_state be set
+ */
+static void r852_dma_enable(struct r852_device *dev)
+{
+       uint8_t dma_reg, dma_irq_reg;
+
+       /* Set up dma settings */
+       dma_reg = r852_read_reg_dword(dev, R852_DMA_SETTINGS);
+       dma_reg &= ~(R852_DMA_READ | R852_DMA_INTERNAL | R852_DMA_MEMORY);
+
+       if (dev->dma_dir)
+               dma_reg |= R852_DMA_READ;
+
+       if (dev->dma_state == DMA_INTERNAL) {
+               dma_reg |= R852_DMA_INTERNAL;
+               /* Precaution to make sure HW doesn't write */
+                       /* to random kernel memory */
+               r852_write_reg_dword(dev, R852_DMA_ADDR,
+                       cpu_to_le32(dev->phys_bounce_buffer));
+       } else {
+               dma_reg |= R852_DMA_MEMORY;
+               r852_write_reg_dword(dev, R852_DMA_ADDR,
+                       cpu_to_le32(dev->phys_dma_addr));
+       }
+
+       /* Precaution: make sure write reached the device */
+       r852_read_reg_dword(dev, R852_DMA_ADDR);
+
+       r852_write_reg_dword(dev, R852_DMA_SETTINGS, dma_reg);
+
+       /* Set dma irq */
+       dma_irq_reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
+       r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
+               dma_irq_reg |
+               R852_DMA_IRQ_INTERNAL |
+               R852_DMA_IRQ_ERROR |
+               R852_DMA_IRQ_MEMORY);
+}
+
+/*
+ * Disable dma, called from the interrupt handler, which specifies
+ * success of the operation via 'error' argument
+ */
+static void r852_dma_done(struct r852_device *dev, int error)
+{
+       WARN_ON(dev->dma_stage == 0);
+
+       r852_write_reg_dword(dev, R852_DMA_IRQ_STA,
+                       r852_read_reg_dword(dev, R852_DMA_IRQ_STA));
+
+       r852_write_reg_dword(dev, R852_DMA_SETTINGS, 0);
+       r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE, 0);
+
+       /* Precaution to make sure HW doesn't write to random kernel memory */
+       r852_write_reg_dword(dev, R852_DMA_ADDR,
+               cpu_to_le32(dev->phys_bounce_buffer));
+       r852_read_reg_dword(dev, R852_DMA_ADDR);
+
+       dev->dma_error = error;
+       dev->dma_stage = 0;
+
+       if (dev->phys_dma_addr && dev->phys_dma_addr != dev->phys_bounce_buffer)
+               pci_unmap_single(dev->pci_dev, dev->phys_dma_addr, R852_DMA_LEN,
+                       dev->dma_dir ? PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE);
+}
+
+/*
+ * Wait, till dma is done, which includes both phases of it
+ */
+static int r852_dma_wait(struct r852_device *dev)
+{
+       long timeout = wait_for_completion_timeout(&dev->dma_done,
+                               msecs_to_jiffies(1000));
+       if (!timeout) {
+               dbg("timeout waiting for DMA interrupt");
+               return -ETIMEDOUT;
+       }
+
+       return 0;
+}
+
+/*
+ * Read/Write one page using dma. Only pages can be read (512 bytes)
+*/
+static void r852_do_dma(struct r852_device *dev, uint8_t *buf, int do_read)
+{
+       int bounce = 0;
+       unsigned long flags;
+       int error;
+
+       dev->dma_error = 0;
+
+       /* Set dma direction */
+       dev->dma_dir = do_read;
+       dev->dma_stage = 1;
+       reinit_completion(&dev->dma_done);
+
+       dbg_verbose("doing dma %s ", do_read ? "read" : "write");
+
+       /* Set initial dma state: for reading first fill on board buffer,
+         from device, for writes first fill the buffer  from memory*/
+       dev->dma_state = do_read ? DMA_INTERNAL : DMA_MEMORY;
+
+       /* if incoming buffer is not page aligned, we should do bounce */
+       if ((unsigned long)buf & (R852_DMA_LEN-1))
+               bounce = 1;
+
+       if (!bounce) {
+               dev->phys_dma_addr = pci_map_single(dev->pci_dev, (void *)buf,
+                       R852_DMA_LEN,
+                       (do_read ? PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE));
+
+               if (pci_dma_mapping_error(dev->pci_dev, dev->phys_dma_addr))
+                       bounce = 1;
+       }
+
+       if (bounce) {
+               dbg_verbose("dma: using bounce buffer");
+               dev->phys_dma_addr = dev->phys_bounce_buffer;
+               if (!do_read)
+                       memcpy(dev->bounce_buffer, buf, R852_DMA_LEN);
+       }
+
+       /* Enable DMA */
+       spin_lock_irqsave(&dev->irqlock, flags);
+       r852_dma_enable(dev);
+       spin_unlock_irqrestore(&dev->irqlock, flags);
+
+       /* Wait till complete */
+       error = r852_dma_wait(dev);
+
+       if (error) {
+               r852_dma_done(dev, error);
+               return;
+       }
+
+       if (do_read && bounce)
+               memcpy((void *)buf, dev->bounce_buffer, R852_DMA_LEN);
+}
+
+/*
+ * Program data lines of the nand chip to send data to it
+ */
+static void r852_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+       uint32_t reg;
+
+       /* Don't allow any access to hardware if we suspect card removal */
+       if (dev->card_unstable)
+               return;
+
+       /* Special case for whole sector read */
+       if (len == R852_DMA_LEN && dev->dma_usable) {
+               r852_do_dma(dev, (uint8_t *)buf, 0);
+               return;
+       }
+
+       /* write DWORD chinks - faster */
+       while (len >= 4) {
+               reg = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24;
+               r852_write_reg_dword(dev, R852_DATALINE, reg);
+               buf += 4;
+               len -= 4;
+
+       }
+
+       /* write rest */
+       while (len > 0) {
+               r852_write_reg(dev, R852_DATALINE, *buf++);
+               len--;
+       }
+}
+
+/*
+ * Read data lines of the nand chip to retrieve data
+ */
+static void r852_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+       uint32_t reg;
+
+       if (dev->card_unstable) {
+               /* since we can't signal error here, at least, return
+                       predictable buffer */
+               memset(buf, 0, len);
+               return;
+       }
+
+       /* special case for whole sector read */
+       if (len == R852_DMA_LEN && dev->dma_usable) {
+               r852_do_dma(dev, buf, 1);
+               return;
+       }
+
+       /* read in dword sized chunks */
+       while (len >= 4) {
+
+               reg = r852_read_reg_dword(dev, R852_DATALINE);
+               *buf++ = reg & 0xFF;
+               *buf++ = (reg >> 8) & 0xFF;
+               *buf++ = (reg >> 16) & 0xFF;
+               *buf++ = (reg >> 24) & 0xFF;
+               len -= 4;
+       }
+
+       /* read the reset by bytes */
+       while (len--)
+               *buf++ = r852_read_reg(dev, R852_DATALINE);
+}
+
+/*
+ * Read one byte from nand chip
+ */
+static uint8_t r852_read_byte(struct mtd_info *mtd)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+
+       /* Same problem as in r852_read_buf.... */
+       if (dev->card_unstable)
+               return 0;
+
+       return r852_read_reg(dev, R852_DATALINE);
+}
+
+/*
+ * Control several chip lines & send commands
+ */
+static void r852_cmdctl(struct mtd_info *mtd, int dat, unsigned int ctrl)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+
+       if (dev->card_unstable)
+               return;
+
+       if (ctrl & NAND_CTRL_CHANGE) {
+
+               dev->ctlreg &= ~(R852_CTL_DATA | R852_CTL_COMMAND |
+                                R852_CTL_ON | R852_CTL_CARDENABLE);
+
+               if (ctrl & NAND_ALE)
+                       dev->ctlreg |= R852_CTL_DATA;
+
+               if (ctrl & NAND_CLE)
+                       dev->ctlreg |= R852_CTL_COMMAND;
+
+               if (ctrl & NAND_NCE)
+                       dev->ctlreg |= (R852_CTL_CARDENABLE | R852_CTL_ON);
+               else
+                       dev->ctlreg &= ~R852_CTL_WRITE;
+
+               /* when write is stareted, enable write access */
+               if (dat == NAND_CMD_ERASE1)
+                       dev->ctlreg |= R852_CTL_WRITE;
+
+               r852_write_reg(dev, R852_CTL, dev->ctlreg);
+       }
+
+        /* HACK: NAND_CMD_SEQIN is called without NAND_CTRL_CHANGE, but we need
+               to set write mode */
+       if (dat == NAND_CMD_SEQIN && (dev->ctlreg & R852_CTL_COMMAND)) {
+               dev->ctlreg |= R852_CTL_WRITE;
+               r852_write_reg(dev, R852_CTL, dev->ctlreg);
+       }
+
+       if (dat != NAND_CMD_NONE)
+               r852_write_reg(dev, R852_DATALINE, dat);
+}
+
+/*
+ * Wait till card is ready.
+ * based on nand_wait, but returns errors on DMA error
+ */
+static int r852_wait(struct mtd_info *mtd, struct nand_chip *chip)
+{
+       struct r852_device *dev = chip->priv;
+
+       unsigned long timeout;
+       int status;
+
+       timeout = jiffies + (chip->state == FL_ERASING ?
+               msecs_to_jiffies(400) : msecs_to_jiffies(20));
+
+       while (time_before(jiffies, timeout))
+               if (chip->dev_ready(mtd))
+                       break;
+
+       chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
+       status = (int)chip->read_byte(mtd);
+
+       /* Unfortunelly, no way to send detailed error status... */
+       if (dev->dma_error) {
+               status |= NAND_STATUS_FAIL;
+               dev->dma_error = 0;
+       }
+       return status;
+}
+
+/*
+ * Check if card is ready
+ */
+
+static int r852_ready(struct mtd_info *mtd)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+       return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY);
+}
+
+
+/*
+ * Set ECC engine mode
+*/
+
+static void r852_ecc_hwctl(struct mtd_info *mtd, int mode)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+
+       if (dev->card_unstable)
+               return;
+
+       switch (mode) {
+       case NAND_ECC_READ:
+       case NAND_ECC_WRITE:
+               /* enable ecc generation/check*/
+               dev->ctlreg |= R852_CTL_ECC_ENABLE;
+
+               /* flush ecc buffer */
+               r852_write_reg(dev, R852_CTL,
+                       dev->ctlreg | R852_CTL_ECC_ACCESS);
+
+               r852_read_reg_dword(dev, R852_DATALINE);
+               r852_write_reg(dev, R852_CTL, dev->ctlreg);
+               return;
+
+       case NAND_ECC_READSYN:
+               /* disable ecc generation */
+               dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
+               r852_write_reg(dev, R852_CTL, dev->ctlreg);
+       }
+}
+
+/*
+ * Calculate ECC, only used for writes
+ */
+
+static int r852_ecc_calculate(struct mtd_info *mtd, const uint8_t *dat,
+                                                       uint8_t *ecc_code)
+{
+       struct r852_device *dev = r852_get_dev(mtd);
+       struct sm_oob *oob = (struct sm_oob *)ecc_code;
+       uint32_t ecc1, ecc2;
+
+       if (dev->card_unstable)
+               return 0;
+
+       dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
+       r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
+
+       ecc1 = r852_read_reg_dword(dev, R852_DATALINE);
+       ecc2 = r852_read_reg_dword(dev, R852_DATALINE);
+
+       oob->ecc1[0] = (ecc1) & 0xFF;
+       oob->ecc1[1] = (ecc1 >> 8) & 0xFF;
+       oob->ecc1[2] = (ecc1 >> 16) & 0xFF;
+
+       oob->ecc2[0] = (ecc2) & 0xFF;
+       oob->ecc2[1] = (ecc2 >> 8) & 0xFF;
+       oob->ecc2[2] = (ecc2 >> 16) & 0xFF;
+
+       r852_write_reg(dev, R852_CTL, dev->ctlreg);
+       return 0;
+}
+
+/*
+ * Correct the data using ECC, hw did almost everything for us
+ */
+
+static int r852_ecc_correct(struct mtd_info *mtd, uint8_t *dat,
+                               uint8_t *read_ecc, uint8_t *calc_ecc)
+{
+       uint16_t ecc_reg;
+       uint8_t ecc_status, err_byte;
+       int i, error = 0;
+
+       struct r852_device *dev = r852_get_dev(mtd);
+
+       if (dev->card_unstable)
+               return 0;
+
+       if (dev->dma_error) {
+               dev->dma_error = 0;
+               return -1;
+       }
+
+       r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
+       ecc_reg = r852_read_reg_dword(dev, R852_DATALINE);
+       r852_write_reg(dev, R852_CTL, dev->ctlreg);
+
+       for (i = 0 ; i <= 1 ; i++) {
+
+               ecc_status = (ecc_reg >> 8) & 0xFF;
+
+               /* ecc uncorrectable error */
+               if (ecc_status & R852_ECC_FAIL) {
+                       dbg("ecc: unrecoverable error, in half %d", i);
+                       error = -1;
+                       goto exit;
+               }
+
+               /* correctable error */
+               if (ecc_status & R852_ECC_CORRECTABLE) {
+
+                       err_byte = ecc_reg & 0xFF;
+                       dbg("ecc: recoverable error, "
+                               "in half %d, byte %d, bit %d", i,
+                               err_byte, ecc_status & R852_ECC_ERR_BIT_MSK);
+
+                       dat[err_byte] ^=
+                               1 << (ecc_status & R852_ECC_ERR_BIT_MSK);
+                       error++;
+               }
+
+               dat += 256;
+               ecc_reg >>= 16;
+       }
+exit:
+       return error;
+}
+
+/*
+ * This is copy of nand_read_oob_std
+ * nand_read_oob_syndrome assumes we can send column address - we can't
+ */
+static int r852_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+                            int page)
+{
+       chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
+       chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+       return 0;
+}
+
+/*
+ * Start the nand engine
+ */
+
+static void r852_engine_enable(struct r852_device *dev)
+{
+       if (r852_read_reg_dword(dev, R852_HW) & R852_HW_UNKNOWN) {
+               r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
+               r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
+       } else {
+               r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
+               r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
+       }
+       msleep(300);
+       r852_write_reg(dev, R852_CTL, 0);
+}
+
+
+/*
+ * Stop the nand engine
+ */
+
+static void r852_engine_disable(struct r852_device *dev)
+{
+       r852_write_reg_dword(dev, R852_HW, 0);
+       r852_write_reg(dev, R852_CTL, R852_CTL_RESET);
+}
+
+/*
+ * Test if card is present
+ */
+
+static void r852_card_update_present(struct r852_device *dev)
+{
+       unsigned long flags;
+       uint8_t reg;
+
+       spin_lock_irqsave(&dev->irqlock, flags);
+       reg = r852_read_reg(dev, R852_CARD_STA);
+       dev->card_detected = !!(reg & R852_CARD_STA_PRESENT);
+       spin_unlock_irqrestore(&dev->irqlock, flags);
+}
+
+/*
+ * Update card detection IRQ state according to current card state
+ * which is read in r852_card_update_present
+ */
+static void r852_update_card_detect(struct r852_device *dev)
+{
+       int card_detect_reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
+       dev->card_unstable = 0;
+
+       card_detect_reg &= ~(R852_CARD_IRQ_REMOVE | R852_CARD_IRQ_INSERT);
+       card_detect_reg |= R852_CARD_IRQ_GENABLE;
+
+       card_detect_reg |= dev->card_detected ?
+               R852_CARD_IRQ_REMOVE : R852_CARD_IRQ_INSERT;
+
+       r852_write_reg(dev, R852_CARD_IRQ_ENABLE, card_detect_reg);
+}
+
+static ssize_t r852_media_type_show(struct device *sys_dev,
+                       struct device_attribute *attr, char *buf)
+{
+       struct mtd_info *mtd = container_of(sys_dev, struct mtd_info, dev);
+       struct r852_device *dev = r852_get_dev(mtd);
+       char *data = dev->sm ? "smartmedia" : "xd";
+
+       strcpy(buf, data);
+       return strlen(data);
+}
+
+static DEVICE_ATTR(media_type, S_IRUGO, r852_media_type_show, NULL);
+
+
+/* Detect properties of card in slot */
+static void r852_update_media_status(struct r852_device *dev)
+{
+       uint8_t reg;
+       unsigned long flags;
+       int readonly;
+
+       spin_lock_irqsave(&dev->irqlock, flags);
+       if (!dev->card_detected) {
+               message("card removed");
+               spin_unlock_irqrestore(&dev->irqlock, flags);
+               return ;
+       }
+
+       readonly  = r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_RO;
+       reg = r852_read_reg(dev, R852_DMA_CAP);
+       dev->sm = (reg & (R852_DMA1 | R852_DMA2)) && (reg & R852_SMBIT);
+
+       message("detected %s %s card in slot",
+               dev->sm ? "SmartMedia" : "xD",
+               readonly ? "readonly" : "writeable");
+
+       dev->readonly = readonly;
+       spin_unlock_irqrestore(&dev->irqlock, flags);
+}
+
+/*
+ * Register the nand device
+ * Called when the card is detected
+ */
+static int r852_register_nand_device(struct r852_device *dev)
+{
+       dev->mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
+
+       if (!dev->mtd)
+               goto error1;
+
+       WARN_ON(dev->card_registred);
+
+       dev->mtd->owner = THIS_MODULE;
+       dev->mtd->priv = dev->chip;
+       dev->mtd->dev.parent = &dev->pci_dev->dev;
+
+       if (dev->readonly)
+               dev->chip->options |= NAND_ROM;
+
+       r852_engine_enable(dev);
+
+       if (sm_register_device(dev->mtd, dev->sm))
+               goto error2;
+
+       if (device_create_file(&dev->mtd->dev, &dev_attr_media_type))
+               message("can't create media type sysfs attribute");
+
+       dev->card_registred = 1;
+       return 0;
+error2:
+       kfree(dev->mtd);
+error1:
+       /* Force card redetect */
+       dev->card_detected = 0;
+       return -1;
+}
+
+/*
+ * Unregister the card
+ */
+
+static void r852_unregister_nand_device(struct r852_device *dev)
+{
+       if (!dev->card_registred)
+               return;
+
+       device_remove_file(&dev->mtd->dev, &dev_attr_media_type);
+       nand_release(dev->mtd);
+       r852_engine_disable(dev);
+       dev->card_registred = 0;
+       kfree(dev->mtd);
+       dev->mtd = NULL;
+}
+
+/* Card state updater */
+static void r852_card_detect_work(struct work_struct *work)
+{
+       struct r852_device *dev =
+               container_of(work, struct r852_device, card_detect_work.work);
+
+       r852_card_update_present(dev);
+       r852_update_card_detect(dev);
+       dev->card_unstable = 0;
+
+       /* False alarm */
+       if (dev->card_detected == dev->card_registred)
+               goto exit;
+
+       /* Read media properties */
+       r852_update_media_status(dev);
+
+       /* Register the card */
+       if (dev->card_detected)
+               r852_register_nand_device(dev);
+       else
+               r852_unregister_nand_device(dev);
+exit:
+       r852_update_card_detect(dev);
+}
+
+/* Ack + disable IRQ generation */
+static void r852_disable_irqs(struct r852_device *dev)
+{
+       uint8_t reg;
+       reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
+       r852_write_reg(dev, R852_CARD_IRQ_ENABLE, reg & ~R852_CARD_IRQ_MASK);
+
+       reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
+       r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
+                                       reg & ~R852_DMA_IRQ_MASK);
+
+       r852_write_reg(dev, R852_CARD_IRQ_STA, R852_CARD_IRQ_MASK);
+       r852_write_reg_dword(dev, R852_DMA_IRQ_STA, R852_DMA_IRQ_MASK);
+}
+
+/* Interrupt handler */
+static irqreturn_t r852_irq(int irq, void *data)
+{
+       struct r852_device *dev = (struct r852_device *)data;
+
+       uint8_t card_status, dma_status;
+       unsigned long flags;
+       irqreturn_t ret = IRQ_NONE;
+
+       spin_lock_irqsave(&dev->irqlock, flags);
+
+       /* handle card detection interrupts first */
+       card_status = r852_read_reg(dev, R852_CARD_IRQ_STA);
+       r852_write_reg(dev, R852_CARD_IRQ_STA, card_status);
+
+       if (card_status & (R852_CARD_IRQ_INSERT|R852_CARD_IRQ_REMOVE)) {
+
+               ret = IRQ_HANDLED;
+               dev->card_detected = !!(card_status & R852_CARD_IRQ_INSERT);
+
+               /* we shouldn't receive any interrupts if we wait for card
+                       to settle */
+               WARN_ON(dev->card_unstable);
+
+               /* disable irqs while card is unstable */
+               /* this will timeout DMA if active, but better that garbage */
+               r852_disable_irqs(dev);
+
+               if (dev->card_unstable)
+                       goto out;
+
+               /* let, card state to settle a bit, and then do the work */
+               dev->card_unstable = 1;
+               queue_delayed_work(dev->card_workqueue,
+                       &dev->card_detect_work, msecs_to_jiffies(100));
+               goto out;
+       }
+
+
+       /* Handle dma interrupts */
+       dma_status = r852_read_reg_dword(dev, R852_DMA_IRQ_STA);
+       r852_write_reg_dword(dev, R852_DMA_IRQ_STA, dma_status);
+
+       if (dma_status & R852_DMA_IRQ_MASK) {
+
+               ret = IRQ_HANDLED;
+
+               if (dma_status & R852_DMA_IRQ_ERROR) {
+                       dbg("received dma error IRQ");
+                       r852_dma_done(dev, -EIO);
+                       complete(&dev->dma_done);
+                       goto out;
+               }
+
+               /* received DMA interrupt out of nowhere? */
+               WARN_ON_ONCE(dev->dma_stage == 0);
+
+               if (dev->dma_stage == 0)
+                       goto out;
+
+               /* done device access */
+               if (dev->dma_state == DMA_INTERNAL &&
+                               (dma_status & R852_DMA_IRQ_INTERNAL)) {
+
+                       dev->dma_state = DMA_MEMORY;
+                       dev->dma_stage++;
+               }
+
+               /* done memory DMA */
+               if (dev->dma_state == DMA_MEMORY &&
+                               (dma_status & R852_DMA_IRQ_MEMORY)) {
+                       dev->dma_state = DMA_INTERNAL;
+                       dev->dma_stage++;
+               }
+
+               /* Enable 2nd half of dma dance */
+               if (dev->dma_stage == 2)
+                       r852_dma_enable(dev);
+
+               /* Operation done */
+               if (dev->dma_stage == 3) {
+                       r852_dma_done(dev, 0);
+                       complete(&dev->dma_done);
+               }
+               goto out;
+       }
+
+       /* Handle unknown interrupts */
+       if (dma_status)
+               dbg("bad dma IRQ status = %x", dma_status);
+
+       if (card_status & ~R852_CARD_STA_CD)
+               dbg("strange card status = %x", card_status);
+
+out:
+       spin_unlock_irqrestore(&dev->irqlock, flags);
+       return ret;
+}
+
+static int  r852_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
+{
+       int error;
+       struct nand_chip *chip;
+       struct r852_device *dev;
+
+       /* pci initialization */
+       error = pci_enable_device(pci_dev);
+
+       if (error)
+               goto error1;
+
+       pci_set_master(pci_dev);
+
+       error = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(32));
+       if (error)
+               goto error2;
+
+       error = pci_request_regions(pci_dev, DRV_NAME);
+
+       if (error)
+               goto error3;
+
+       error = -ENOMEM;
+
+       /* init nand chip, but register it only on card insert */
+       chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
+
+       if (!chip)
+               goto error4;
+
+       /* commands */
+       chip->cmd_ctrl = r852_cmdctl;
+       chip->waitfunc = r852_wait;
+       chip->dev_ready = r852_ready;
+
+       /* I/O */
+       chip->read_byte = r852_read_byte;
+       chip->read_buf = r852_read_buf;
+       chip->write_buf = r852_write_buf;
+
+       /* ecc */
+       chip->ecc.mode = NAND_ECC_HW_SYNDROME;
+       chip->ecc.size = R852_DMA_LEN;
+       chip->ecc.bytes = SM_OOB_SIZE;
+       chip->ecc.strength = 2;
+       chip->ecc.hwctl = r852_ecc_hwctl;
+       chip->ecc.calculate = r852_ecc_calculate;
+       chip->ecc.correct = r852_ecc_correct;
+
+       /* TODO: hack */
+       chip->ecc.read_oob = r852_read_oob;
+
+       /* init our device structure */
+       dev = kzalloc(sizeof(struct r852_device), GFP_KERNEL);
+
+       if (!dev)
+               goto error5;
+
+       chip->priv = dev;
+       dev->chip = chip;
+       dev->pci_dev = pci_dev;
+       pci_set_drvdata(pci_dev, dev);
+
+       dev->bounce_buffer = pci_alloc_consistent(pci_dev, R852_DMA_LEN,
+               &dev->phys_bounce_buffer);
+
+       if (!dev->bounce_buffer)
+               goto error6;
+
+
+       error = -ENODEV;
+       dev->mmio = pci_ioremap_bar(pci_dev, 0);
+
+       if (!dev->mmio)
+               goto error7;
+
+       error = -ENOMEM;
+       dev->tmp_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
+
+       if (!dev->tmp_buffer)
+               goto error8;
+
+       init_completion(&dev->dma_done);
+
+       dev->card_workqueue = create_freezable_workqueue(DRV_NAME);
+
+       if (!dev->card_workqueue)
+               goto error9;
+
+       INIT_DELAYED_WORK(&dev->card_detect_work, r852_card_detect_work);
+
+       /* shutdown everything - precation */
+       r852_engine_disable(dev);
+       r852_disable_irqs(dev);
+
+       r852_dma_test(dev);
+
+       dev->irq = pci_dev->irq;
+       spin_lock_init(&dev->irqlock);
+
+       dev->card_detected = 0;
+       r852_card_update_present(dev);
+
+       /*register irq handler*/
+       error = -ENODEV;
+       if (request_irq(pci_dev->irq, &r852_irq, IRQF_SHARED,
+                         DRV_NAME, dev))
+               goto error10;
+
+       /* kick initial present test */
+       queue_delayed_work(dev->card_workqueue,
+               &dev->card_detect_work, 0);
+
+
+       printk(KERN_NOTICE DRV_NAME ": driver loaded successfully\n");
+       return 0;
+
+error10:
+       destroy_workqueue(dev->card_workqueue);
+error9:
+       kfree(dev->tmp_buffer);
+error8:
+       pci_iounmap(pci_dev, dev->mmio);
+error7:
+       pci_free_consistent(pci_dev, R852_DMA_LEN,
+               dev->bounce_buffer, dev->phys_bounce_buffer);
+error6:
+       kfree(dev);
+error5:
+       kfree(chip);
+error4:
+       pci_release_regions(pci_dev);
+error3:
+error2:
+       pci_disable_device(pci_dev);
+error1:
+       return error;
+}
+
+static void r852_remove(struct pci_dev *pci_dev)
+{
+       struct r852_device *dev = pci_get_drvdata(pci_dev);
+
+       /* Stop detect workqueue -
+               we are going to unregister the device anyway*/
+       cancel_delayed_work_sync(&dev->card_detect_work);
+       destroy_workqueue(dev->card_workqueue);
+
+       /* Unregister the device, this might make more IO */
+       r852_unregister_nand_device(dev);
+
+       /* Stop interrupts */
+       r852_disable_irqs(dev);
+       synchronize_irq(dev->irq);
+       free_irq(dev->irq, dev);
+
+       /* Cleanup */
+       kfree(dev->tmp_buffer);
+       pci_iounmap(pci_dev, dev->mmio);
+       pci_free_consistent(pci_dev, R852_DMA_LEN,
+               dev->bounce_buffer, dev->phys_bounce_buffer);
+
+       kfree(dev->chip);
+       kfree(dev);
+
+       /* Shutdown the PCI device */
+       pci_release_regions(pci_dev);
+       pci_disable_device(pci_dev);
+}
+
+static void r852_shutdown(struct pci_dev *pci_dev)
+{
+       struct r852_device *dev = pci_get_drvdata(pci_dev);
+
+       cancel_delayed_work_sync(&dev->card_detect_work);
+       r852_disable_irqs(dev);
+       synchronize_irq(dev->irq);
+       pci_disable_device(pci_dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int r852_suspend(struct device *device)
+{
+       struct r852_device *dev = pci_get_drvdata(to_pci_dev(device));
+
+       if (dev->ctlreg & R852_CTL_CARDENABLE)
+               return -EBUSY;
+
+       /* First make sure the detect work is gone */
+       cancel_delayed_work_sync(&dev->card_detect_work);
+
+       /* Turn off the interrupts and stop the device */
+       r852_disable_irqs(dev);
+       r852_engine_disable(dev);
+
+       /* If card was pulled off just during the suspend, which is very
+               unlikely, we will remove it on resume, it too late now
+               anyway... */
+       dev->card_unstable = 0;
+       return 0;
+}
+
+static int r852_resume(struct device *device)
+{
+       struct r852_device *dev = pci_get_drvdata(to_pci_dev(device));
+
+       r852_disable_irqs(dev);
+       r852_card_update_present(dev);
+       r852_engine_disable(dev);
+
+
+       /* If card status changed, just do the work */
+       if (dev->card_detected != dev->card_registred) {
+               dbg("card was %s during low power state",
+                       dev->card_detected ? "added" : "removed");
+
+               queue_delayed_work(dev->card_workqueue,
+               &dev->card_detect_work, msecs_to_jiffies(1000));
+               return 0;
+       }
+
+       /* Otherwise, initialize the card */
+       if (dev->card_registred) {
+               r852_engine_enable(dev);
+               dev->chip->select_chip(dev->mtd, 0);
+               dev->chip->cmdfunc(dev->mtd, NAND_CMD_RESET, -1, -1);
+               dev->chip->select_chip(dev->mtd, -1);
+       }
+
+       /* Program card detection IRQ */
+       r852_update_card_detect(dev);
+       return 0;
+}
+#endif
+
+static const struct pci_device_id r852_pci_id_tbl[] = {
+
+       { PCI_VDEVICE(RICOH, 0x0852), },
+       { },
+};
+
+MODULE_DEVICE_TABLE(pci, r852_pci_id_tbl);
+
+static SIMPLE_DEV_PM_OPS(r852_pm_ops, r852_suspend, r852_resume);
+
+static struct pci_driver r852_pci_driver = {
+       .name           = DRV_NAME,
+       .id_table       = r852_pci_id_tbl,
+       .probe          = r852_probe,
+       .remove         = r852_remove,
+       .shutdown       = r852_shutdown,
+       .driver.pm      = &r852_pm_ops,
+};
+
+module_pci_driver(r852_pci_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
+MODULE_DESCRIPTION("Ricoh 85xx xD/smartmedia card reader driver");