[MTD] [NAND] Blackfin on-chip NAND Flash Controller driver

This is the driver for latest Blackfin on-chip nand flash controller

 - use nand_chip and mtd_info common nand driver interface
 - provide both PIO and dma operation
 - compiled with ezkit bf548 configuration
 - use hardware 1-bit ECC
 - tested with YAFFS2 and can mount YAFFS2 filesystem as rootfs

ChangeLog from try#1
 - use hweight32() instead of count_bits()
 - replace bf54x with bf5xx and BF54X with BF5XX
 - compare against plat->page_size in 2 cases when enable hardware ECC

ChangeLog from try#2
 - passed nand_test suites
 - use cpu_relax() instead of busy wait loop
 - some coding style issue pointed out by Andrew

Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 788 insertions, 0 deletions

diff --git a/drivers/mtd/nand/bf5xx_nand.c b/drivers/mtd/nand/bf5xx_nand.c
new file mode 100644
index 000000000000..1657ecd74881
--- /dev/null
+++ b/drivers/mtd/nand/bf5xx_nand.c
@@ -0,0 +1,788 @@
+/* linux/drivers/mtd/nand/bf5xx_nand.c
+ *
+ * Copyright 2006-2007 Analog Devices Inc.
+ *      http://blackfin.uclinux.org/
+ *      Bryan Wu <bryan.wu@analog.com>
+ *
+ * Blackfin BF5xx on-chip NAND flash controler driver
+ *
+ * Derived from drivers/mtd/nand/s3c2410.c
+ * Copyright (c) 2007 Ben Dooks <ben@simtec.co.uk>
+ *
+ * Derived from drivers/mtd/nand/cafe.c
+ * Copyright © 2006 Red Hat, Inc.
+ * Copyright © 2006 David Woodhouse <dwmw2@infradead.org>
+ *
+ * Changelog:
+ *      12-Jun-2007  Bryan Wu:  Initial version
+ *      18-Jul-2007  Bryan Wu:
+ *              - ECC_HW and ECC_SW supported
+ *              - DMA supported in ECC_HW
+ *              - YAFFS tested as rootfs in both ECC_HW and ECC_SW
+ *
+ * TODO:
+ *      Enable JFFS2 over NAND as rootfs
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/bitops.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/blackfin.h>
+#include <asm/dma.h>
+#include <asm/cacheflush.h>
+#include <asm/nand.h>
+#include <asm/portmux.h>
+
+#define DRV_NAME        "bf5xx-nand"
+#define DRV_VERSION     "1.2"
+#define DRV_AUTHOR      "Bryan Wu <bryan.wu@analog.com>"
+#define DRV_DESC        "BF5xx on-chip NAND FLash Controller Driver"
+
+#ifdef CONFIG_MTD_NAND_BF5XX_HWECC
+static int hardware_ecc = 1;
+#else
+static int hardware_ecc;
+#endif
+
+static unsigned short bfin_nfc_pin_req[] = {P_NAND_CE, P_NAND_RB, 0};
+
+/*
+ * Data structures for bf5xx nand flash controller driver
+ */
+
+/* bf5xx nand info */
+struct bf5xx_nand_info {
+        /* mtd info */
+        struct nand_hw_control          controller;
+        struct mtd_info                 mtd;
+        struct nand_chip                chip;
+
+        /* platform info */
+        struct bf5xx_nand_platform      *platform;
+
+        /* device info */
+        struct device                   *device;
+
+        /* DMA stuff */
+        struct completion               dma_completion;
+};
+
+/*
+ * Conversion functions
+ */
+static struct bf5xx_nand_info *mtd_to_nand_info(struct mtd_info *mtd)
+{
+        return container_of(mtd, struct bf5xx_nand_info, mtd);
+}
+
+static struct bf5xx_nand_info *to_nand_info(struct platform_device *pdev)
+{
+        return platform_get_drvdata(pdev);
+}
+
+static struct bf5xx_nand_platform *to_nand_plat(struct platform_device *pdev)
+{
+        return pdev->dev.platform_data;
+}
+
+/*
+ * struct nand_chip interface function pointers
+ */
+
+/*
+ * bf5xx_nand_hwcontrol
+ *
+ * Issue command and address cycles to the chip
+ */
+static void bf5xx_nand_hwcontrol(struct mtd_info *mtd, int cmd,
+                                   unsigned int ctrl)
+{
+        if (cmd == NAND_CMD_NONE)
+                return;
+
+        while (bfin_read_NFC_STAT() & WB_FULL)
+                cpu_relax();
+
+        if (ctrl & NAND_CLE)
+                bfin_write_NFC_CMD(cmd);
+        else
+                bfin_write_NFC_ADDR(cmd);
+        SSYNC();
+}
+
+/*
+ * bf5xx_nand_devready()
+ *
+ * returns 0 if the nand is busy, 1 if it is ready
+ */
+static int bf5xx_nand_devready(struct mtd_info *mtd)
+{
+        unsigned short val = bfin_read_NFC_IRQSTAT();
+
+        if ((val & NBUSYIRQ) == NBUSYIRQ)
+                return 1;
+        else
+                return 0;
+}
+
+/*
+ * ECC functions
+ * These allow the bf5xx to use the controller's ECC
+ * generator block to ECC the data as it passes through
+ */
+
+/*
+ * ECC error correction function
+ */
+static int bf5xx_nand_correct_data_256(struct mtd_info *mtd, u_char *dat,
+                                        u_char *read_ecc, u_char *calc_ecc)
+{
+        struct bf5xx_nand_info *info = mtd_to_nand_info(mtd);
+        u32 syndrome[5];
+        u32 calced, stored;
+        int i;
+        unsigned short failing_bit, failing_byte;
+        u_char data;
+
+        calced = calc_ecc[0] | (calc_ecc[1] << 8) | (calc_ecc[2] << 16);
+        stored = read_ecc[0] | (read_ecc[1] << 8) | (read_ecc[2] << 16);
+
+        syndrome[0] = (calced ^ stored);
+
+        /*
+         * syndrome 0: all zero
+         * No error in data
+         * No action
+         */
+        if (!syndrome[0] || !calced || !stored)
+                return 0;
+
+        /*
+         * sysdrome 0: only one bit is one
+         * ECC data was incorrect
+         * No action
+         */
+        if (hweight32(syndrome[0]) == 1) {
+                dev_err(info->device, "ECC data was incorrect!\n");
+                return 1;
+        }
+
+        syndrome[1] = (calced & 0x7FF) ^ (stored & 0x7FF);
+        syndrome[2] = (calced & 0x7FF) ^ ((calced >> 11) & 0x7FF);
+        syndrome[3] = (stored & 0x7FF) ^ ((stored >> 11) & 0x7FF);
+        syndrome[4] = syndrome[2] ^ syndrome[3];
+
+        for (i = 0; i < 5; i++)
+                dev_info(info->device, "syndrome[%d] 0x%08x\n", i, syndrome[i]);
+
+        dev_info(info->device,
+                "calced[0x%08x], stored[0x%08x]\n",
+                calced, stored);
+
+        /*
+         * sysdrome 0: exactly 11 bits are one, each parity
+         * and parity' pair is 1 & 0 or 0 & 1.
+         * 1-bit correctable error
+         * Correct the error
+         */
+        if (hweight32(syndrome[0]) == 11 && syndrome[4] == 0x7FF) {
+                dev_info(info->device,
+                        "1-bit correctable error, correct it.\n");
+                dev_info(info->device,
+                        "syndrome[1] 0x%08x\n", syndrome[1]);
+
+                failing_bit = syndrome[1] & 0x7;
+                failing_byte = syndrome[1] >> 0x3;
+                data = *(dat + failing_byte);
+                data = data ^ (0x1 << failing_bit);
+                *(dat + failing_byte) = data;
+
+                return 0;
+        }
+
+        /*
+         * sysdrome 0: random data
+         * More than 1-bit error, non-correctable error
+         * Discard data, mark bad block
+         */
+        dev_err(info->device,
+                "More than 1-bit error, non-correctable error.\n");
+        dev_err(info->device,
+                "Please discard data, mark bad block\n");
+
+        return 1;
+}
+
+static int bf5xx_nand_correct_data(struct mtd_info *mtd, u_char *dat,
+                                        u_char *read_ecc, u_char *calc_ecc)
+{
+        struct bf5xx_nand_info *info = mtd_to_nand_info(mtd);
+        struct bf5xx_nand_platform *plat = info->platform;
+        unsigned short page_size = (plat->page_size ? 512 : 256);
+        int ret;
+
+        ret = bf5xx_nand_correct_data_256(mtd, dat, read_ecc, calc_ecc);
+
+        /* If page size is 512, correct second 256 bytes */
+        if (page_size == 512) {
+                dat += 256;
+                read_ecc += 8;
+                calc_ecc += 8;
+                ret = bf5xx_nand_correct_data_256(mtd, dat, read_ecc, calc_ecc);
+        }
+
+        return ret;
+}
+
+static void bf5xx_nand_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+        return;
+}
+
+static int bf5xx_nand_calculate_ecc(struct mtd_info *mtd,
+                const u_char *dat, u_char *ecc_code)
+{
+        struct bf5xx_nand_info *info = mtd_to_nand_info(mtd);
+        struct bf5xx_nand_platform *plat = info->platform;
+        u16 page_size = (plat->page_size ? 512 : 256);
+        u16 ecc0, ecc1;
+        u32 code[2];
+        u8 *p;
+        int bytes = 3, i;
+
+        /* first 4 bytes ECC code for 256 page size */
+        ecc0 = bfin_read_NFC_ECC0();
+        ecc1 = bfin_read_NFC_ECC1();
+
+        code[0] = (ecc0 & 0x3FF) | ((ecc1 & 0x3FF) << 11);
+
+        dev_dbg(info->device, "returning ecc 0x%08x\n", code[0]);
+
+        /* second 4 bytes ECC code for 512 page size */
+        if (page_size == 512) {
+                ecc0 = bfin_read_NFC_ECC2();
+                ecc1 = bfin_read_NFC_ECC3();
+                code[1] = (ecc0 & 0x3FF) | ((ecc1 & 0x3FF) << 11);
+                bytes = 6;
+                dev_dbg(info->device, "returning ecc 0x%08x\n", code[1]);
+        }
+
+        p = (u8 *)code;
+        for (i = 0; i < bytes; i++)
+                ecc_code[i] = p[i];
+
+        return 0;
+}
+
+/*
+ * PIO mode for buffer writing and reading
+ */
+static void bf5xx_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+        int i;
+        unsigned short val;
+
+        /*
+         * Data reads are requested by first writing to NFC_DATA_RD
+         * and then reading back from NFC_READ.
+         */
+        for (i = 0; i < len; i++) {
+                while (bfin_read_NFC_STAT() & WB_FULL)
+                        cpu_relax();
+
+                /* Contents do not matter */
+                bfin_write_NFC_DATA_RD(0x0000);
+                SSYNC();
+
+                while ((bfin_read_NFC_IRQSTAT() & RD_RDY) != RD_RDY)
+                        cpu_relax();
+
+                buf[i] = bfin_read_NFC_READ();
+
+                val = bfin_read_NFC_IRQSTAT();
+                val |= RD_RDY;
+                bfin_write_NFC_IRQSTAT(val);
+                SSYNC();
+        }
+}
+
+static uint8_t bf5xx_nand_read_byte(struct mtd_info *mtd)
+{
+        uint8_t val;
+
+        bf5xx_nand_read_buf(mtd, &val, 1);
+
+        return val;
+}
+
+static void bf5xx_nand_write_buf(struct mtd_info *mtd,
+                                const uint8_t *buf, int len)
+{
+        int i;
+
+        for (i = 0; i < len; i++) {
+                while (bfin_read_NFC_STAT() & WB_FULL)
+                        cpu_relax();
+
+                bfin_write_NFC_DATA_WR(buf[i]);
+                SSYNC();
+        }
+}
+
+static void bf5xx_nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+        int i;
+        u16 *p = (u16 *) buf;
+        len >>= 1;
+
+        /*
+         * Data reads are requested by first writing to NFC_DATA_RD
+         * and then reading back from NFC_READ.
+         */
+        bfin_write_NFC_DATA_RD(0x5555);
+
+        SSYNC();
+
+        for (i = 0; i < len; i++)
+                p[i] = bfin_read_NFC_READ();
+}
+
+static void bf5xx_nand_write_buf16(struct mtd_info *mtd,
+                                const uint8_t *buf, int len)
+{
+        int i;
+        u16 *p = (u16 *) buf;
+        len >>= 1;
+
+        for (i = 0; i < len; i++)
+                bfin_write_NFC_DATA_WR(p[i]);
+
+        SSYNC();
+}
+
+/*
+ * DMA functions for buffer writing and reading
+ */
+static irqreturn_t bf5xx_nand_dma_irq(int irq, void *dev_id)
+{
+        struct bf5xx_nand_info *info = dev_id;
+
+        clear_dma_irqstat(CH_NFC);
+        disable_dma(CH_NFC);
+        complete(&info->dma_completion);
+
+        return IRQ_HANDLED;
+}
+
+static int bf5xx_nand_dma_rw(struct mtd_info *mtd,
+                                uint8_t *buf, int is_read)
+{
+        struct bf5xx_nand_info *info = mtd_to_nand_info(mtd);
+        struct bf5xx_nand_platform *plat = info->platform;
+        unsigned short page_size = (plat->page_size ? 512 : 256);
+        unsigned short val;
+
+        dev_dbg(info->device, " mtd->%p, buf->%p, is_read %d\n",
+                        mtd, buf, is_read);
+
+        /*
+         * Before starting a dma transfer, be sure to invalidate/flush
+         * the cache over the address range of your DMA buffer to
+         * prevent cache coherency problems. Otherwise very subtle bugs
+         * can be introduced to your driver.
+         */
+        if (is_read)
+                invalidate_dcache_range((unsigned int)buf,
+                                (unsigned int)(buf + page_size));
+        else
+                flush_dcache_range((unsigned int)buf,
+                                (unsigned int)(buf + page_size));
+
+        /*
+         * This register must be written before each page is
+         * transferred to generate the correct ECC register
+         * values.
+         */
+        bfin_write_NFC_RST(0x1);
+        SSYNC();
+
+        disable_dma(CH_NFC);
+        clear_dma_irqstat(CH_NFC);
+
+        /* setup DMA register with Blackfin DMA API */
+        set_dma_config(CH_NFC, 0x0);
+        set_dma_start_addr(CH_NFC, (unsigned long) buf);
+        set_dma_x_count(CH_NFC, (page_size >> 2));
+        set_dma_x_modify(CH_NFC, 4);
+
+        /* setup write or read operation */
+        val = DI_EN | WDSIZE_32;
+        if (is_read)
+                val |= WNR;
+        set_dma_config(CH_NFC, val);
+        enable_dma(CH_NFC);
+
+        /* Start PAGE read/write operation */
+        if (is_read)
+                bfin_write_NFC_PGCTL(0x1);
+        else
+                bfin_write_NFC_PGCTL(0x2);
+        wait_for_completion(&info->dma_completion);
+
+        return 0;
+}
+
+static void bf5xx_nand_dma_read_buf(struct mtd_info *mtd,
+                                        uint8_t *buf, int len)
+{
+        struct bf5xx_nand_info *info = mtd_to_nand_info(mtd);
+        struct bf5xx_nand_platform *plat = info->platform;
+        unsigned short page_size = (plat->page_size ? 512 : 256);
+
+        dev_dbg(info->device, "mtd->%p, buf->%p, int %d\n", mtd, buf, len);
+
+        if (len == page_size)
+                bf5xx_nand_dma_rw(mtd, buf, 1);
+        else
+                bf5xx_nand_read_buf(mtd, buf, len);
+}
+
+static void bf5xx_nand_dma_write_buf(struct mtd_info *mtd,
+                                const uint8_t *buf, int len)
+{
+        struct bf5xx_nand_info *info = mtd_to_nand_info(mtd);
+        struct bf5xx_nand_platform *plat = info->platform;
+        unsigned short page_size = (plat->page_size ? 512 : 256);
+
+        dev_dbg(info->device, "mtd->%p, buf->%p, len %d\n", mtd, buf, len);
+
+        if (len == page_size)
+                bf5xx_nand_dma_rw(mtd, (uint8_t *)buf, 0);
+        else
+                bf5xx_nand_write_buf(mtd, buf, len);
+}
+
+/*
+ * System initialization functions
+ */
+
+static int bf5xx_nand_dma_init(struct bf5xx_nand_info *info)
+{
+        int ret;
+        unsigned short val;
+
+        /* Do not use dma */
+        if (!hardware_ecc)
+                return 0;
+
+        init_completion(&info->dma_completion);
+
+        /* Setup DMAC1 channel mux for NFC which shared with SDH */
+        val = bfin_read_DMAC1_PERIMUX();
+        val &= 0xFFFE;
+        bfin_write_DMAC1_PERIMUX(val);
+        SSYNC();
+
+        /* Request NFC DMA channel */
+        ret = request_dma(CH_NFC, "BF5XX NFC driver");
+        if (ret < 0) {
+                dev_err(info->device, " unable to get DMA channel\n");
+                return ret;
+        }
+
+        set_dma_callback(CH_NFC, (void *) bf5xx_nand_dma_irq, (void *) info);
+
+        /* Turn off the DMA channel first */
+        disable_dma(CH_NFC);
+        return 0;
+}
+
+/*
+ * BF5XX NFC hardware initialization
+ *  - pin mux setup
+ *  - clear interrupt status
+ */
+static int bf5xx_nand_hw_init(struct bf5xx_nand_info *info)
+{
+        int err = 0;
+        unsigned short val;
+        struct bf5xx_nand_platform *plat = info->platform;
+
+        /* setup NFC_CTL register */
+        dev_info(info->device,
+                "page_size=%d, data_width=%d, wr_dly=%d, rd_dly=%d\n",
+                (plat->page_size ? 512 : 256),
+                (plat->data_width ? 16 : 8),
+                plat->wr_dly, plat->rd_dly);
+
+        val = (plat->page_size << NFC_PG_SIZE_OFFSET) |
+                (plat->data_width << NFC_NWIDTH_OFFSET) |
+                (plat->rd_dly << NFC_RDDLY_OFFSET) |
+                (plat->rd_dly << NFC_WRDLY_OFFSET);
+        dev_dbg(info->device, "NFC_CTL is 0x%04x\n", val);
+
+        bfin_write_NFC_CTL(val);
+        SSYNC();
+
+        /* clear interrupt status */
+        bfin_write_NFC_IRQMASK(0x0);
+        SSYNC();
+        val = bfin_read_NFC_IRQSTAT();
+        bfin_write_NFC_IRQSTAT(val);
+        SSYNC();
+
+        if (peripheral_request_list(bfin_nfc_pin_req, DRV_NAME)) {
+                printk(KERN_ERR DRV_NAME
+                ": Requesting Peripherals failed\n");
+                return -EFAULT;
+        }
+
+        /* DMA initialization  */
+        if (bf5xx_nand_dma_init(info))
+                err = -ENXIO;
+
+        return err;
+}
+
+/*
+ * Device management interface
+ */
+static int bf5xx_nand_add_partition(struct bf5xx_nand_info *info)
+{
+        struct mtd_info *mtd = &info->mtd;
+
+#ifdef CONFIG_MTD_PARTITIONS
+        struct mtd_partition *parts = info->platform->partitions;
+        int nr = info->platform->nr_partitions;
+
+        return add_mtd_partitions(mtd, parts, nr);
+#else
+        return add_mtd_device(mtd);
+#endif
+}
+
+static int bf5xx_nand_remove(struct platform_device *pdev)
+{
+        struct bf5xx_nand_info *info = to_nand_info(pdev);
+        struct mtd_info *mtd = NULL;
+
+        platform_set_drvdata(pdev, NULL);
+
+        /* first thing we need to do is release all our mtds
+         * and their partitions, then go through freeing the
+         * resources used
+         */
+        mtd = &info->mtd;
+        if (mtd) {
+                nand_release(mtd);
+                kfree(mtd);
+        }
+
+        peripheral_free_list(bfin_nfc_pin_req);
+
+        /* free the common resources */
+        kfree(info);
+
+        return 0;
+}
+
+/*
+ * bf5xx_nand_probe
+ *
+ * called by device layer when it finds a device matching
+ * one our driver can handled. This code checks to see if
+ * it can allocate all necessary resources then calls the
+ * nand layer to look for devices
+ */
+static int bf5xx_nand_probe(struct platform_device *pdev)
+{
+        struct bf5xx_nand_platform *plat = to_nand_plat(pdev);
+        struct bf5xx_nand_info *info = NULL;
+        struct nand_chip *chip = NULL;
+        struct mtd_info *mtd = NULL;
+        int err = 0;
+
+        dev_dbg(&pdev->dev, "(%p)\n", pdev);
+
+        if (!plat) {
+                dev_err(&pdev->dev, "no platform specific information\n");
+                goto exit_error;
+        }
+
+        info = kzalloc(sizeof(*info), GFP_KERNEL);
+        if (info == NULL) {
+                dev_err(&pdev->dev, "no memory for flash info\n");
+                err = -ENOMEM;
+                goto exit_error;
+        }
+
+        platform_set_drvdata(pdev, info);
+
+        spin_lock_init(&info->controller.lock);
+        init_waitqueue_head(&info->controller.wq);
+
+        info->device     = &pdev->dev;
+        info->platform   = plat;
+
+        /* initialise chip data struct */
+        chip = &info->chip;
+
+        if (plat->data_width)
+                chip->options |= NAND_BUSWIDTH_16;
+
+        chip->options |= NAND_CACHEPRG | NAND_SKIP_BBTSCAN;
+
+        chip->read_buf = (plat->data_width) ?
+                bf5xx_nand_read_buf16 : bf5xx_nand_read_buf;
+        chip->write_buf = (plat->data_width) ?
+                bf5xx_nand_write_buf16 : bf5xx_nand_write_buf;
+
+        chip->read_byte    = bf5xx_nand_read_byte;
+
+        chip->cmd_ctrl     = bf5xx_nand_hwcontrol;
+        chip->dev_ready    = bf5xx_nand_devready;
+
+        chip->priv         = &info->mtd;
+        chip->controller   = &info->controller;
+
+        chip->IO_ADDR_R    = (void __iomem *) NFC_READ;
+        chip->IO_ADDR_W    = (void __iomem *) NFC_DATA_WR;
+
+        chip->chip_delay   = 0;
+
+        /* initialise mtd info data struct */
+        mtd             = &info->mtd;
+        mtd->priv       = chip;
+        mtd->owner      = THIS_MODULE;
+
+        /* initialise the hardware */
+        err = bf5xx_nand_hw_init(info);
+        if (err != 0)
+                goto exit_error;
+
+        /* setup hardware ECC data struct */
+        if (hardware_ecc) {
+                if (plat->page_size == NFC_PG_SIZE_256) {
+                        chip->ecc.bytes = 3;
+                        chip->ecc.size = 256;
+                } else if (plat->page_size == NFC_PG_SIZE_512) {
+                        chip->ecc.bytes = 6;
+                        chip->ecc.size = 512;
+                }
+
+                chip->read_buf      = bf5xx_nand_dma_read_buf;
+                chip->write_buf     = bf5xx_nand_dma_write_buf;
+                chip->ecc.calculate = bf5xx_nand_calculate_ecc;
+                chip->ecc.correct   = bf5xx_nand_correct_data;
+                chip->ecc.mode      = NAND_ECC_HW;
+                chip->ecc.hwctl     = bf5xx_nand_enable_hwecc;
+        } else {
+                chip->ecc.mode      = NAND_ECC_SOFT;
+        }
+
+        /* scan hardware nand chip and setup mtd info data struct */
+        if (nand_scan(mtd, 1)) {
+                err = -ENXIO;
+                goto exit_error;
+        }
+
+        /* add NAND partition */
+        bf5xx_nand_add_partition(info);
+
+        dev_dbg(&pdev->dev, "initialised ok\n");
+        return 0;
+
+exit_error:
+        bf5xx_nand_remove(pdev);
+
+        if (err == 0)
+                err = -EINVAL;
+        return err;
+}
+
+/* PM Support */
+#ifdef CONFIG_PM
+
+static int bf5xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
+{
+        struct bf5xx_nand_info *info = platform_get_drvdata(dev);
+
+        return 0;
+}
+
+static int bf5xx_nand_resume(struct platform_device *dev)
+{
+        struct bf5xx_nand_info *info = platform_get_drvdata(dev);
+
+        if (info)
+                bf5xx_nand_hw_init(info);
+
+        return 0;
+}
+
+#else
+#define bf5xx_nand_suspend NULL
+#define bf5xx_nand_resume NULL
+#endif
+
+/* driver device registration */
+static struct platform_driver bf5xx_nand_driver = {
+        .probe          = bf5xx_nand_probe,
+        .remove         = bf5xx_nand_remove,
+        .suspend        = bf5xx_nand_suspend,
+        .resume         = bf5xx_nand_resume,
+        .driver         = {
+                .name   = DRV_NAME,
+                .owner  = THIS_MODULE,
+        },
+};
+
+static int __init bf5xx_nand_init(void)
+{
+        printk(KERN_INFO "%s, Version %s (c) 2007 Analog Devices, Inc.\n",
+                DRV_DESC, DRV_VERSION);
+
+        return platform_driver_register(&bf5xx_nand_driver);
+}
+
+static void __exit bf5xx_nand_exit(void)
+{
+        platform_driver_unregister(&bf5xx_nand_driver);
+}
+
+module_init(bf5xx_nand_init);
+module_exit(bf5xx_nand_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRV_AUTHOR);
+MODULE_DESCRIPTION(DRV_DESC);