[RFC 1/5] mtd:fsl_nfc: Nand flash controller for VF610, MPC5125, etc.

Bill Pringlemeir bpringlemeir at nbsps.com
Wed Jan 8 18:07:17 EST 2014


Limitations:
- Untested on MPC5125, MCF54418 and Kinetis K70.
- DMA not used.
- 2K pages or less.
- No hardware ECC.

Signed-off-by: Bill Pringlemeir <bpringlemeir at nbsps.com>
---
 drivers/mtd/nand/Kconfig   |  12 +
 drivers/mtd/nand/Makefile  |   1 +
 drivers/mtd/nand/fsl_nfc.c | 676 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 689 insertions(+)
 create mode 100644 drivers/mtd/nand/fsl_nfc.c

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 93ae6a6..7e0c695 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -449,6 +449,18 @@ config MTD_NAND_MPC5121_NFC
 	  This enables the driver for the NAND flash controller on the
 	  MPC5121 SoC.
 
+config HAVE_NAND_FSL_NFC
+	bool
+
+config MTD_NAND_FSL_NFC
+	tristate "Support for Freescale NFC"
+	depends on HAVE_NAND_FSL_NFC
+	help
+	  Enables support for NAND Flash controller on some Freescale
+	  processors like the MPC5125, VF610, MCF54418, and Kinetis K70.
+	  The driver supports a maximum 2k page size.
+	  The driver currently does not support hardware ECC.
+
 config MTD_NAND_MXC
 	tristate "MXC NAND support"
 	depends on ARCH_MXC
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 542b568..116f827 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_MTD_NAND_PASEMI)		+= pasemi_nand.o
 obj-$(CONFIG_MTD_NAND_ORION)		+= orion_nand.o
 obj-$(CONFIG_MTD_NAND_FSL_ELBC)		+= fsl_elbc_nand.o
 obj-$(CONFIG_MTD_NAND_FSL_IFC)		+= fsl_ifc_nand.o
+obj-$(CONFIG_MTD_NAND_FSL_NFC)		+= fsl_nfc.o
 obj-$(CONFIG_MTD_NAND_FSL_UPM)		+= fsl_upm.o
 obj-$(CONFIG_MTD_NAND_SLC_LPC32XX)      += lpc32xx_slc.o
 obj-$(CONFIG_MTD_NAND_MLC_LPC32XX)      += lpc32xx_mlc.o
diff --git a/drivers/mtd/nand/fsl_nfc.c b/drivers/mtd/nand/fsl_nfc.c
new file mode 100644
index 0000000..eb4e353
--- /dev/null
+++ b/drivers/mtd/nand/fsl_nfc.c
@@ -0,0 +1,676 @@
+/*
+ * Copyright 2009-2012 Freescale Semiconductor, Inc.
+ *
+ * Description: MPC5125, VF610, MCF54418 and Kinetis K70 Nand driver.
+ * Jason ported to M54418TWR and MVFA5.
+ * Authors: Shaohui Xie <b21989 at freescale.com>
+ *          Jason Jin <Jason.jin at freescale.com>
+ *
+ * Based on original driver mpc5121_nfc.c.
+ *
+ * This 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.
+ *
+ * Limitations:
+ * - Untested on MPC5125 and M54418.
+ * - DMA not used.
+ * - 2K pages or less.
+ */
+
+#include <linux/module.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/of_mtd.h>
+
+#define	DRV_NAME		"fsl_nfc"
+
+/* Register Offsets */
+#define NFC_FLASH_CMD1			0x3F00
+#define NFC_FLASH_CMD2			0x3F04
+#define NFC_COL_ADDR			0x3F08
+#define NFC_ROW_ADDR			0x3F0c
+#define NFC_ROW_ADDR_INC		0x3F14
+#define NFC_FLASH_STATUS1		0x3F18
+#define NFC_FLASH_STATUS2		0x3F1c
+#define NFC_CACHE_SWAP			0x3F28
+#define NFC_SECTOR_SIZE			0x3F2c
+#define NFC_FLASH_CONFIG		0x3F30
+#define NFC_IRQ_STATUS			0x3F38
+
+/* Addresses for NFC MAIN RAM BUFFER areas */
+#define NFC_MAIN_AREA(n)		((n) *  0x1000)
+
+#define PAGE_2K				0x0800
+#define OOB_64				0x0040
+
+/* NFC_CMD2[CODE] values. See section:
+    - 31.4.7 Flash Command Code Description, Vybrid manual
+    - 23.8.6 Flash Command Sequencer, MPC5125 manual
+
+    Briefly these are bitmasks of controller cycles.
+*/
+#define READ_PAGE_CMD_CODE		0x7EE0
+#define PROGRAM_PAGE_CMD_CODE	0x7FC0
+#define ERASE_CMD_CODE			0x4EC0
+#define READ_ID_CMD_CODE		0x4804
+#define RESET_CMD_CODE			0x4040
+#define STATUS_READ_CMD_CODE	0x4068
+
+/* NFC ECC mode define */
+#define ECC_BYPASS			0
+
+/*** Register Mask and bit definitions */
+
+/* NFC_FLASH_CMD1 Field */
+#define CMD_BYTE2_MASK				0xFF000000
+#define CMD_BYTE2_SHIFT				24
+
+/* NFC_FLASH_CM2 Field */
+#define CMD_BYTE1_MASK				0xFF000000
+#define CMD_BYTE1_SHIFT				24
+#define CMD_CODE_MASK				0x00FFFF00
+#define CMD_CODE_SHIFT				8
+#define BUFNO_MASK				0x00000006
+#define BUFNO_SHIFT				1
+#define START_BIT				(1<<0)
+
+/* NFC_COL_ADDR Field */
+#define COL_ADDR_MASK				0x0000FFFF
+#define COL_ADDR_SHIFT				0
+
+/* NFC_ROW_ADDR Field */
+#define ROW_ADDR_MASK				0x00FFFFFF
+#define ROW_ADDR_SHIFT				0
+#define ROW_ADDR_CHIP_SEL_RB_MASK		0xF0000000
+#define ROW_ADDR_CHIP_SEL_RB_SHIFT		28
+#define ROW_ADDR_CHIP_SEL_MASK			0x0F000000
+#define ROW_ADDR_CHIP_SEL_SHIFT			24
+
+/* NFC_FLASH_STATUS2 Field */
+#define STATUS_BYTE1_MASK			0x000000FF
+
+/* NFC_FLASH_CONFIG Field */
+#define CONFIG_ECC_SRAM_REQ_BIT			(1<<21)
+#define CONFIG_DMA_REQ_BIT			(1<<20)
+#define CONFIG_ECC_MODE_MASK			0x000E0000
+#define CONFIG_ECC_MODE_SHIFT			17
+#define CONFIG_FAST_FLASH_BIT			(1<<16)
+#define CONFIG_16BIT				(1<<7)
+#define CONFIG_BOOT_MODE_BIT			(1<<6)
+#define CONFIG_ADDR_AUTO_INCR_BIT		(1<<5)
+#define CONFIG_BUFNO_AUTO_INCR_BIT		(1<<4)
+#define CONFIG_PAGE_CNT_MASK			0xF
+#define CONFIG_PAGE_CNT_SHIFT			0
+
+/* NFC_IRQ_STATUS Field */
+#define IDLE_IRQ_BIT				(1<<29)
+#define IDLE_EN_BIT				(1<<20)
+#define CMD_DONE_CLEAR_BIT			(1<<18)
+#define IDLE_CLEAR_BIT				(1<<17)
+
+#define NFC_TIMEOUT		(HZ)
+
+struct fsl_nfc {
+	struct mtd_info	   mtd;
+	struct nand_chip   chip;
+	struct device	  *dev;
+	void __iomem	  *regs;
+	wait_queue_head_t  irq_waitq;
+	uint               column;
+	int                spareonly;
+	int                page;
+	/* Status and ID are in alternate locations. */
+	int                alt_buf;
+#define ALT_BUF_ID   1
+#define ALT_BUF_STAT 2
+	struct clk        *clk;
+};
+#define mtd_to_nfc(_mtd) container_of(_mtd, struct fsl_nfc, mtd)
+
+static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
+static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
+
+static struct nand_bbt_descr bbt_main_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
+		   NAND_BBT_2BIT | NAND_BBT_VERSION,
+	.offs =	11,
+	.len = 4,
+	.veroffs = 15,
+	.maxblocks = 4,
+	.pattern = bbt_pattern,
+};
+
+static struct nand_bbt_descr bbt_mirror_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
+		   NAND_BBT_2BIT | NAND_BBT_VERSION,
+	.offs =	11,
+	.len = 4,
+	.veroffs = 15,
+	.maxblocks = 4,
+	.pattern = mirror_pattern,
+};
+
+static u32 nfc_read(struct mtd_info *mtd, uint reg)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+	if (reg == NFC_FLASH_STATUS1 ||
+	    reg == NFC_FLASH_STATUS2 ||
+	    reg == NFC_IRQ_STATUS)
+		return __raw_readl(nfc->regs + reg);
+	/* Gang read/writes together for most registers. */
+	else
+		return *(u32 *)(nfc->regs + reg);
+}
+
+static void nfc_write(struct mtd_info *mtd, uint reg, u32 val)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+
+	if (reg == NFC_FLASH_STATUS1 ||
+	    reg == NFC_FLASH_STATUS2 ||
+	    reg == NFC_IRQ_STATUS)
+		__raw_writel(val, nfc->regs + reg);
+	/* Gang read/writes together for most registers. */
+	else
+		*(u32 *)(nfc->regs + reg) = val;
+}
+
+static void nfc_set(struct mtd_info *mtd, uint reg, u32 bits)
+{
+	nfc_write(mtd, reg, nfc_read(mtd, reg) | bits);
+}
+
+static void nfc_clear(struct mtd_info *mtd, uint reg, u32 bits)
+{
+	nfc_write(mtd, reg, nfc_read(mtd, reg) & ~bits);
+}
+
+static void nfc_set_field(struct mtd_info *mtd, u32 reg,
+			  u32 mask, u32 shift, u32 val)
+{
+	nfc_write(mtd, reg, (nfc_read(mtd, reg) & (~mask)) | val << shift);
+}
+
+/* Clear flags for upcoming command */
+static void nfc_clear_status(struct mtd_info *mtd)
+{
+	nfc_set(mtd, NFC_IRQ_STATUS, CMD_DONE_CLEAR_BIT);
+	nfc_set(mtd, NFC_IRQ_STATUS, IDLE_CLEAR_BIT);
+}
+
+/* Wait for complete operation */
+static void nfc_done(struct mtd_info *mtd)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+	int rv;
+
+	nfc_set(mtd, NFC_IRQ_STATUS, IDLE_EN_BIT);
+	/* CMD2 is almost non-volatile, START_BIT is not */
+	barrier();
+	nfc_set(mtd, NFC_FLASH_CMD2, START_BIT);
+	barrier();
+
+	if (!(nfc_read(mtd, NFC_IRQ_STATUS) & IDLE_IRQ_BIT)) {
+		rv = wait_event_timeout(nfc->irq_waitq,
+			(nfc_read(mtd, NFC_IRQ_STATUS) & IDLE_IRQ_BIT),
+					NFC_TIMEOUT);
+		if (!rv)
+			dev_warn(nfc->dev, "Timeout while waiting for BUSY.\n");
+	}
+	nfc_clear_status(mtd);
+}
+
+static u8 nfc_get_id(struct mtd_info *mtd, int col)
+{
+	u32 flash_id;
+
+	if (col < 4) {
+		flash_id = nfc_read(mtd, NFC_FLASH_STATUS1);
+		return (flash_id >> (3-col)*8) & 0xff;
+	} else {
+		flash_id = nfc_read(mtd, NFC_FLASH_STATUS2);
+		return flash_id >> 24;
+	}
+}
+
+static u8 nfc_get_status(struct mtd_info *mtd)
+{
+	return nfc_read(mtd, NFC_FLASH_STATUS2) & STATUS_BYTE1_MASK;
+}
+
+/* Single command */
+static void nfc_send_command(struct mtd_info *mtd, u32 cmd_byte1,
+			     u32 cmd_code)
+{
+	nfc_clear_status(mtd);
+
+	nfc_set_field(mtd, NFC_FLASH_CMD2, CMD_BYTE1_MASK,
+			CMD_BYTE1_SHIFT, cmd_byte1);
+
+	nfc_clear(mtd, NFC_FLASH_CMD2, BUFNO_MASK);
+
+	nfc_set_field(mtd, NFC_FLASH_CMD2, CMD_CODE_MASK,
+			CMD_CODE_SHIFT, cmd_code);
+}
+
+/* Two commands */
+static void nfc_send_commands(struct mtd_info *mtd, u32 cmd_byte1,
+			      u32 cmd_byte2, u32 cmd_code)
+{
+	nfc_send_command(mtd, cmd_byte1, cmd_code);
+
+	nfc_set_field(mtd, NFC_FLASH_CMD1, CMD_BYTE2_MASK,
+			CMD_BYTE2_SHIFT, cmd_byte2);
+}
+
+static irqreturn_t nfc_irq(int irq, void *data)
+{
+	struct mtd_info *mtd = data;
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+
+	nfc_clear(mtd, NFC_IRQ_STATUS, IDLE_EN_BIT);
+	wake_up(&nfc->irq_waitq);
+
+	return IRQ_HANDLED;
+}
+
+static void nfc_addr_cycle(struct mtd_info *mtd, int column, int page)
+{
+	if (column != -1) {
+		struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+		if (nfc->chip.options | NAND_BUSWIDTH_16)
+			column = column/2;
+		nfc_set_field(mtd, NFC_COL_ADDR, COL_ADDR_MASK,
+			      COL_ADDR_SHIFT, column);
+	}
+	if (page != -1)
+		nfc_set_field(mtd, NFC_ROW_ADDR, ROW_ADDR_MASK,
+				ROW_ADDR_SHIFT, page);
+}
+
+/* Send command to NAND chip */
+static void nfc_command(struct mtd_info *mtd, unsigned command,
+			int column, int page)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+
+	nfc->column     = max(column, 0);
+	nfc->spareonly	= 0;
+	nfc->alt_buf	= 0;
+
+	switch (command) {
+	case NAND_CMD_PAGEPROG:
+		nfc->page = -1;
+		nfc_send_commands(mtd, NAND_CMD_SEQIN,
+			     command, PROGRAM_PAGE_CMD_CODE);
+		nfc_addr_cycle(mtd, column, page);
+		break;
+
+	case NAND_CMD_RESET:
+		nfc_send_command(mtd, command, RESET_CMD_CODE);
+		break;
+	/*
+	 * NFC does not support sub-page reads and writes,
+	 * so emulate them using full page transfers.
+	 */
+	case NAND_CMD_READOOB:
+		nfc->spareonly = 1;
+	case NAND_CMD_SEQIN: /* Pre-read for partial writes. */
+	case NAND_CMD_READ0:
+		column = 0;
+		/* Already read? */
+		if (nfc->page == page)
+			return;
+		nfc->page = page;
+		nfc_send_commands(mtd, NAND_CMD_READ0,
+				  NAND_CMD_READSTART, READ_PAGE_CMD_CODE);
+		nfc_addr_cycle(mtd, column, page);
+		break;
+
+	case NAND_CMD_ERASE1:
+		if (nfc->page == page)
+			nfc->page = -1;
+		nfc_send_commands(mtd, command,
+				  NAND_CMD_ERASE2, ERASE_CMD_CODE);
+		nfc_addr_cycle(mtd, column, page);
+		break;
+
+	case NAND_CMD_READID:
+		nfc->alt_buf = ALT_BUF_ID;
+		nfc_send_command(mtd, command, READ_ID_CMD_CODE);
+		break;
+
+	case NAND_CMD_STATUS:
+		nfc->alt_buf = ALT_BUF_STAT;
+		nfc_send_command(mtd, command, STATUS_READ_CMD_CODE);
+		break;
+	default:
+		return;
+	}
+
+	nfc_done(mtd);
+}
+
+static void nfc_read_spare(struct mtd_info *mtd, void *buf, int len)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+
+	len = min(mtd->oobsize, (uint)len);
+	if (len > 0)
+		memcpy(buf, nfc->regs + mtd->writesize, len);
+}
+
+/* Read data from NFC buffers */
+static void nfc_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+	uint c = nfc->column;
+	uint l;
+
+	/* Handle main area */
+	if (!nfc->spareonly) {
+
+		l = min((uint)len, mtd->writesize - c);
+		nfc->column += l;
+
+		if (!nfc->alt_buf)
+			memcpy(buf, nfc->regs + NFC_MAIN_AREA(0) + c, l);
+		else
+			if (nfc->alt_buf & ALT_BUF_ID)
+				*buf = nfc_get_id(mtd, c);
+			else
+				*buf = nfc_get_status(mtd);
+		buf += l;
+		len -= l;
+	}
+
+	/* Handle spare area access */
+	if (len) {
+		nfc->column += len;
+		nfc_read_spare(mtd, buf, len);
+	}
+}
+
+/* Write data to NFC buffers */
+static void nfc_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+	uint c = nfc->column;
+	uint l;
+
+	l = min((uint)len, mtd->writesize + mtd->oobsize - c);
+	nfc->column += l;
+
+	memcpy(nfc->regs + NFC_MAIN_AREA(0) + c, buf, l);
+}
+
+/* Read byte from NFC buffers */
+static u8 nfc_read_byte(struct mtd_info *mtd)
+{
+	u8 tmp;
+	nfc_read_buf(mtd, &tmp, sizeof(tmp));
+	return tmp;
+}
+
+/* Read word from NFC buffers */
+static u16 nfc_read_word(struct mtd_info *mtd)
+{
+	u16 tmp;
+	nfc_read_buf(mtd, (u_char *)&tmp, sizeof(tmp));
+	return tmp;
+}
+
+/* If not provided, upper layers apply a fixed delay. */
+static int nfc_dev_ready(struct mtd_info *mtd)
+{
+	/* NFC handles R/B internally; always ready.  */
+	return 1;
+}
+
+/* Vybrid only.  MPC5125 has full RB and four CS. Assume boot loader
+ * has set this register for now.
+ */
+static void
+nfc_select_chip(struct mtd_info *mtd, int chip)
+{
+#ifdef CONFIG_SOC_VF610
+	nfc_set_field(mtd, NFC_ROW_ADDR, ROW_ADDR_CHIP_SEL_RB_MASK,
+		      ROW_ADDR_CHIP_SEL_RB_SHIFT, 1);
+
+	if (chip == 0)
+		nfc_set_field(mtd, NFC_ROW_ADDR, ROW_ADDR_CHIP_SEL_MASK,
+			      ROW_ADDR_CHIP_SEL_SHIFT, 1);
+	else if (chip == 1)
+		nfc_set_field(mtd, NFC_ROW_ADDR, ROW_ADDR_CHIP_SEL_MASK,
+			      ROW_ADDR_CHIP_SEL_SHIFT, 2);
+	else
+		nfc_clear(mtd, NFC_ROW_ADDR, ROW_ADDR_CHIP_SEL_MASK);
+#endif
+}
+
+struct nfc_config {
+	int width;
+	int flash_bbt;
+	u32 clkrate;
+};
+
+#ifdef CONFIG_OF_MTD
+static struct of_device_id nfc_dt_ids[] = {
+	{ .compatible = "fsl,vf610-nfc" },
+	{ .compatible = "fsl,mpc5125-nfc" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, nfc_dt_ids);
+
+static int __init nfc_probe_dt(struct device *dev, struct nfc_config *cfg)
+{
+	struct device_node *np = dev->of_node;
+	int buswidth;
+	u32 clkrate;
+
+	memset(cfg, 0, sizeof(*cfg));
+
+	if (!np)
+		return 1;
+
+	cfg->flash_bbt = of_get_nand_on_flash_bbt(np);
+
+	if (!of_property_read_u32(np, "clock-frequency", &clkrate))
+		cfg->clkrate = clkrate;
+
+	buswidth = of_get_nand_bus_width(np);
+	if (buswidth < 0)
+		return buswidth;
+
+	cfg->width = buswidth;
+
+	return 0;
+}
+#else
+static int __init nfc_probe_dt(struct device *dev, struct nfc_config *cfg)
+{
+	memset(cfg, 0, sizeof(*cfg));
+	return 0;
+}
+#endif
+
+static int nfc_probe(struct platform_device *pdev)
+{
+	struct fsl_nfc *nfc;
+	struct resource *res;
+	struct mtd_info *mtd;
+	struct nand_chip *chip;
+	struct nfc_config cfg;
+	int err = 0;
+	int page_sz;
+	int irq;
+
+	nfc = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL);
+	if (!nfc)
+		return -ENOMEM;
+
+	nfc->dev = &pdev->dev;
+	nfc->page = -1;
+	mtd = &nfc->mtd;
+	chip = &nfc->chip;
+
+	mtd->priv = chip;
+	mtd->owner = THIS_MODULE;
+	mtd->dev.parent = nfc->dev;
+	mtd->name = DRV_NAME;
+
+	err = nfc_probe_dt(nfc->dev, &cfg);
+	if (err)
+		return -ENODEV;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0)
+		return -EINVAL;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	nfc->regs = devm_ioremap_resource(nfc->dev, res);
+	if (IS_ERR(nfc->regs))
+		return PTR_ERR(nfc->regs);
+
+	nfc->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(nfc->clk))
+		return PTR_ERR(nfc->clk);
+
+	if (cfg.clkrate && clk_set_rate(nfc->clk, cfg.clkrate)) {
+		dev_err(nfc->dev, "Clock rate not set.");
+		return -EINVAL;
+	}
+
+	err = clk_prepare_enable(nfc->clk);
+	if (err) {
+		dev_err(nfc->dev, "Unable to enable clock!\n");
+		return err;
+	}
+
+	if (cfg.width == 16) {
+		chip->options |= NAND_BUSWIDTH_16;
+		nfc_set(mtd, NFC_FLASH_CONFIG, CONFIG_16BIT);
+	} else {
+		chip->options &= ~NAND_BUSWIDTH_16;
+		nfc_clear(mtd, NFC_FLASH_CONFIG, CONFIG_16BIT);
+	}
+
+	chip->dev_ready = nfc_dev_ready;
+	chip->cmdfunc = nfc_command;
+	chip->read_byte = nfc_read_byte;
+	chip->read_word = nfc_read_word;
+	chip->read_buf = nfc_read_buf;
+	chip->write_buf = nfc_write_buf;
+	chip->select_chip = nfc_select_chip;
+
+	/* Bad block options. */
+	if (cfg.flash_bbt)
+		chip->bbt_options = NAND_BBT_USE_FLASH | NAND_BBT_CREATE;
+
+	/* Default to software ECC until flash ID. */
+	nfc_set_field(mtd, NFC_FLASH_CONFIG,
+		      CONFIG_ECC_MODE_MASK,
+		      CONFIG_ECC_MODE_SHIFT, ECC_BYPASS);
+
+	chip->bbt_td = &bbt_main_descr;
+	chip->bbt_md = &bbt_mirror_descr;
+
+	init_waitqueue_head(&nfc->irq_waitq);
+
+	err = devm_request_irq(nfc->dev, irq, nfc_irq, 0, DRV_NAME, mtd);
+	if (err) {
+		dev_err(nfc->dev, "Error requesting IRQ!\n");
+		goto error;
+	}
+
+	page_sz = PAGE_2K + OOB_64;
+	page_sz += cfg.width == 16 ? 1 : 0;
+	nfc_write(mtd, NFC_SECTOR_SIZE, page_sz);
+
+	/* Set configuration register. */
+	nfc_clear(mtd, NFC_FLASH_CONFIG, CONFIG_ADDR_AUTO_INCR_BIT);
+	nfc_clear(mtd, NFC_FLASH_CONFIG, CONFIG_BUFNO_AUTO_INCR_BIT);
+	nfc_clear(mtd, NFC_FLASH_CONFIG, CONFIG_BOOT_MODE_BIT);
+	nfc_clear(mtd, NFC_FLASH_CONFIG, CONFIG_DMA_REQ_BIT);
+	nfc_set(mtd, NFC_FLASH_CONFIG, CONFIG_FAST_FLASH_BIT);
+
+	/* PAGE_CNT = 1 */
+	nfc_set_field(mtd, NFC_FLASH_CONFIG, CONFIG_PAGE_CNT_MASK,
+			CONFIG_PAGE_CNT_SHIFT, 1);
+
+	/* first scan to find the device and get the page size */
+	if (nand_scan_ident(mtd, 1, NULL)) {
+		err = -ENXIO;
+		goto error;
+	}
+
+	chip->ecc.mode = NAND_ECC_SOFT; /* default */
+
+	page_sz = mtd->writesize + mtd->oobsize;
+
+	/* Single buffer only, max 256 OOB minus ECC status */
+	if (page_sz > PAGE_2K + 256 - 8) {
+		dev_err(nfc->dev, "Unsupported flash size\n");
+		err = -ENXIO;
+		goto error;
+	}
+	page_sz += cfg.width == 16 ? 1 : 0;
+	nfc_write(mtd, NFC_SECTOR_SIZE, page_sz);
+
+	/* second phase scan */
+	if (nand_scan_tail(mtd)) {
+		err = -ENXIO;
+		goto error;
+	}
+
+	/* Register device in MTD */
+	mtd_device_parse_register(mtd, NULL,
+		&(struct mtd_part_parser_data){
+			.of_node = pdev->dev.of_node,
+		},
+		NULL, 0);
+
+	platform_set_drvdata(pdev, mtd);
+
+	return 0;
+
+error:
+	clk_disable_unprepare(nfc->clk);
+	return err;
+}
+
+static int nfc_remove(struct platform_device *pdev)
+{
+	struct mtd_info *mtd = platform_get_drvdata(pdev);
+	struct fsl_nfc *nfc = mtd_to_nfc(mtd);
+
+	nand_release(mtd);
+	clk_disable_unprepare(nfc->clk);
+	return 0;
+}
+
+static struct platform_driver nfc_driver = {
+	.driver		= {
+		.name	= DRV_NAME,
+		.owner	= THIS_MODULE,
+		.of_match_table = nfc_dt_ids,
+	},
+	.probe		= nfc_probe,
+	.remove		= nfc_remove,
+};
+
+module_platform_driver(nfc_driver);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("FSL NFC MTD driver");
+MODULE_LICENSE("GPL");
-- 
1.8.0.2




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