summaryrefslogtreecommitdiffstats
path: root/drivers/mtd
diff options
context:
space:
mode:
authorBryan Wu <bryan.wu@analog.com>2007-10-02 13:56:05 -0700
committerDavid Woodhouse <dwmw2@infradead.org>2007-10-13 14:36:49 +0100
commitb37bde147890c8fea8369a5a4e230dabdea4ebfb (patch)
treeb447c6b44d7c5b48ead3366db74654c7cc64a4d6 /drivers/mtd
parentc4a9f88daf6c382fedde4cdddef0b30f1d0a20db (diff)
downloadlinux-b37bde147890c8fea8369a5a4e230dabdea4ebfb.tar.bz2
[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>
Diffstat (limited to 'drivers/mtd')
-rw-r--r--drivers/mtd/nand/Kconfig19
-rw-r--r--drivers/mtd/nand/Makefile1
-rw-r--r--drivers/mtd/nand/bf5xx_nand.c788
3 files changed, 808 insertions, 0 deletions
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index d3ec309f2435..8f9c3baeb38e 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -91,6 +91,25 @@ config MTD_NAND_AU1550
This enables the driver for the NAND flash controller on the
AMD/Alchemy 1550 SOC.
+config MTD_NAND_BF5XX
+ tristate "Blackfin on-chip NAND Flash Controller driver"
+ depends on BF54x && MTD_NAND
+ help
+ This enables the Blackfin on-chip NAND flash controller
+
+ No board specific support is done by this driver, each board
+ must advertise a platform_device for the driver to attach.
+
+ This driver can also be built as a module. If so, the module
+ will be called bf5xx-nand.
+
+config MTD_NAND_BF5XX_HWECC
+ bool "BF5XX NAND Hardware ECC"
+ depends on MTD_NAND_BF5XX
+ help
+ Enable the use of the BF5XX's internal ECC generator when
+ using NAND.
+
config MTD_NAND_RTC_FROM4
tristate "Renesas Flash ROM 4-slot interface board (FROM_BOARD4)"
depends on SH_SOLUTION_ENGINE
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 74125611f3ef..3ad6c0165da3 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_MTD_NAND_TOTO) += toto.o
obj-$(CONFIG_MTD_NAND_AUTCPU12) += autcpu12.o
obj-$(CONFIG_MTD_NAND_EDB7312) += edb7312.o
obj-$(CONFIG_MTD_NAND_AU1550) += au1550nd.o
+obj-$(CONFIG_MTD_NAND_BF5XX) += bf5xx_nand.o
obj-$(CONFIG_MTD_NAND_PPCHAMELEONEVB) += ppchameleonevb.o
obj-$(CONFIG_MTD_NAND_S3C2410) += s3c2410.o
obj-$(CONFIG_MTD_NAND_DISKONCHIP) += diskonchip.o
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);