Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1082 insertions, 0 deletions

diff --git a/drivers/mtd/nand/raw/r852.c b/drivers/mtd/nand/raw/r852.c
new file mode 100644
index 000000000..bb74a0ac6
--- /dev/null
+++ b/drivers/mtd/nand/raw/r852.c
@@ -0,0 +1,1082 @@
+/*
+ * 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.
+ */
+
+#define DRV_NAME "r852"
+#define pr_fmt(fmt)  DRV_NAME ": " fmt
+
+#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_to_nand(mtd);
+	return nand_get_controller_data(chip);
+}
+
+
+/* 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 = nand_get_controller_data(chip);
+
+	unsigned long timeout;
+	u8 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;
+
+	nand_status_op(chip, &status);
+
+	/* 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)
+{
+	uint32_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 -EIO;
+	}
+
+	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 = -EBADMSG;
+			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)
+{
+	return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
+}
+
+/*
+ * 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)
+{
+	struct mtd_info *mtd = nand_to_mtd(dev->chip);
+
+	WARN_ON(dev->card_registred);
+
+	mtd->dev.parent = &dev->pci_dev->dev;
+
+	if (dev->readonly)
+		dev->chip->options |= NAND_ROM;
+
+	r852_engine_enable(dev);
+
+	if (sm_register_device(mtd, dev->sm))
+		goto error1;
+
+	if (device_create_file(&mtd->dev, &dev_attr_media_type)) {
+		message("can't create media type sysfs attribute");
+		goto error3;
+	}
+
+	dev->card_registred = 1;
+	return 0;
+error3:
+	nand_release(dev->chip);
+error1:
+	/* Force card redetect */
+	dev->card_detected = 0;
+	return -1;
+}
+
+/*
+ * Unregister the card
+ */
+
+static void r852_unregister_nand_device(struct r852_device *dev)
+{
+	struct mtd_info *mtd = nand_to_mtd(dev->chip);
+
+	if (!dev->card_registred)
+		return;
+
+	device_remove_file(&mtd->dev, &dev_attr_media_type);
+	nand_release(dev->chip);
+	r852_engine_disable(dev);
+	dev->card_registred = 0;
+}
+
+/* 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;
+
+	nand_set_controller_data(chip, 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);
+
+
+	pr_notice("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);
+	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));
+	struct mtd_info *mtd = nand_to_mtd(dev->chip);
+
+	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(mtd, 0);
+		nand_reset_op(dev->chip);
+		dev->chip->select_chip(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");