Staging: MTD: Micron SPINAND Driver support

This patch adds support for Micron SPINAND via MTD.
Signed-off-by: Mona Anonuevo <manonuevo@micron.com>
Signed-off-by: Kamlakant Patel <kamlakant.patel@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/Kconfig

@@ -136,6 +136,8 @@ source "drivers/staging/goldfish/Kconfig"
 
 source "drivers/staging/netlogic/Kconfig"
 
+source "drivers/staging/mt29f_spinand/Kconfig"
+
 source "drivers/staging/dwc2/Kconfig"
 
 source "drivers/staging/lustre/Kconfig"

drivers/staging/Makefile

@@ -66,3 +66,4 @@ obj-$(CONFIG_USB_BTMTK)		+= btmtk_usb/
 obj-$(CONFIG_XILLYBUS)		+= xillybus/
 obj-$(CONFIG_DGNC)			+= dgnc/
 obj-$(CONFIG_DGAP)			+= dgap/
+obj-$(CONFIG_MTD_SPINAND_MT29F)	+= mt29f_spinand/

drivers/staging/mt29f_spinand/Kconfig

+config MTD_SPINAND_MT29F
+	tristate "SPINAND Device Support for Micron"
+	depends on MTD_NAND && SPI
+	help
+	  This enables support for accessing Micron SPI NAND flash
+	  devices.
+	  If you have Micron SPI NAND chip say yes.
+
+	  If unsure, say no here.
+
+config MTD_SPINAND_ONDIEECC
+	bool "Use SPINAND internal ECC"
+	depends on MTD_SPINAND_MT29F
+	help
+	  Internel ECC.
+	  Enables Hardware ECC support for Micron SPI NAND.

drivers/staging/mt29f_spinand/Makefile

+obj-$(CONFIG_MTD_SPINAND_MT29F) += mt29f_spinand.o

drivers/staging/mt29f_spinand/TODO

+TODO:
+	- Tested on XLP platform, needs to be tested on other platforms.
+	- Checkpatch.pl cleanups
+	- Sparce fixes.
+	- Clean up coding style to meet kernel standard.
+
+Please send patches
+To:
+Kamlakant Patel <kamlakant.patel@broadcom.com>
+Cc:
+Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Mona Anonuevo <manonuevo@micron.com>
+linux-mtd@lists.infradead.org

drivers/staging/mt29f_spinand/mt29f_spinand.c

+/*
+ * Copyright (c) 2003-2013 Broadcom Corporation
+ *
+ * Copyright (c) 2009-2010 Micron Technology, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/nand.h>
+#include <linux/spi/spi.h>
+
+#include "mt29f_spinand.h"
+
+#define BUFSIZE (10 * 64 * 2048)
+#define CACHE_BUF 2112
+/*
+ * OOB area specification layout:  Total 32 available free bytes.
+ */
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+static int enable_hw_ecc;
+static int enable_read_hw_ecc;
+
+static inline struct spinand_state *mtd_to_state(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = (struct nand_chip *)mtd->priv;
+	struct spinand_info *info = (struct spinand_info *)chip->priv;
+	struct spinand_state *state = (struct spinand_state *)info->priv;
+
+	return state;
+}
+
+static struct nand_ecclayout spinand_oob_64 = {
+	.eccbytes = 24,
+	.eccpos = {
+		1, 2, 3, 4, 5, 6,
+		17, 18, 19, 20, 21, 22,
+		33, 34, 35, 36, 37, 38,
+		49, 50, 51, 52, 53, 54, },
+	.oobavail = 32,
+	.oobfree = {
+		{.offset = 8,
+			.length = 8},
+		{.offset = 24,
+			.length = 8},
+		{.offset = 40,
+			.length = 8},
+		{.offset = 56,
+			.length = 8},
+	}
+};
+#endif
+
+/*
+ * spinand_cmd - to process a command to send to the SPI Nand
+ * Description:
+ *    Set up the command buffer to send to the SPI controller.
+ *    The command buffer has to initialized to 0.
+ */
+
+static int spinand_cmd(struct spi_device *spi, struct spinand_cmd *cmd)
+{
+	struct spi_message message;
+	struct spi_transfer x[4];
+	u8 dummy = 0xff;
+
+	spi_message_init(&message);
+	memset(x, 0, sizeof(x));
+
+	x[0].len = 1;
+	x[0].tx_buf = &cmd->cmd;
+	spi_message_add_tail(&x[0], &message);
+
+	if (cmd->n_addr) {
+		x[1].len = cmd->n_addr;
+		x[1].tx_buf = cmd->addr;
+		spi_message_add_tail(&x[1], &message);
+	}
+
+	if (cmd->n_dummy) {
+		x[2].len = cmd->n_dummy;
+		x[2].tx_buf = &dummy;
+		spi_message_add_tail(&x[2], &message);
+	}
+
+	if (cmd->n_tx) {
+		x[3].len = cmd->n_tx;
+		x[3].tx_buf = cmd->tx_buf;
+		spi_message_add_tail(&x[3], &message);
+	}
+
+	if (cmd->n_rx) {
+		x[3].len = cmd->n_rx;
+		x[3].rx_buf = cmd->rx_buf;
+		spi_message_add_tail(&x[3], &message);
+	}
+
+	return spi_sync(spi, &message);
+}
+
+/*
+ * spinand_read_id- Read SPI Nand ID
+ * Description:
+ *    Read ID: read two ID bytes from the SPI Nand device
+ */
+static int spinand_read_id(struct spi_device *spi_nand, u8 *id)
+{
+	int retval;
+	u8 nand_id[3];
+	struct spinand_cmd cmd = {0};
+
+	cmd.cmd = CMD_READ_ID;
+	cmd.n_rx = 3;
+	cmd.rx_buf = &nand_id[0];
+
+	retval = spinand_cmd(spi_nand, &cmd);
+	if (retval < 0) {
+		dev_err(&spi_nand->dev, "error %d reading id\n", retval);
+		return retval;
+	}
+	id[0] = nand_id[1];
+	id[1] = nand_id[2];
+	return retval;
+}
+
+/*
+ * spinand_read_status- send command 0xf to the SPI Nand status register
+ * Description:
+ *    After read, write, or erase, the Nand device is expected to set the
+ *    busy status.
+ *    This function is to allow reading the status of the command: read,
+ *    write, and erase.
+ *    Once the status turns to be ready, the other status bits also are
+ *    valid status bits.
+ */
+static int spinand_read_status(struct spi_device *spi_nand, uint8_t *status)
+{
+	struct spinand_cmd cmd = {0};
+	int ret;
+
+	cmd.cmd = CMD_READ_REG;
+	cmd.n_addr = 1;
+	cmd.addr[0] = REG_STATUS;
+	cmd.n_rx = 1;
+	cmd.rx_buf = status;
+
+	ret = spinand_cmd(spi_nand, &cmd);
+	if (ret < 0)
+		dev_err(&spi_nand->dev, "err: %d read status register\n", ret);
+
+	return ret;
+}
+
+#define MAX_WAIT_JIFFIES  (40 * HZ)
+static int wait_till_ready(struct spi_device *spi_nand)
+{
+	unsigned long deadline;
+	int retval;
+	u8 stat = 0;
+
+	deadline = jiffies + MAX_WAIT_JIFFIES;
+	do {
+		retval = spinand_read_status(spi_nand, &stat);
+		if (retval < 0)
+			return -1;
+		else if (!(stat & 0x1))
+			break;
+
+		cond_resched();
+	} while (!time_after_eq(jiffies, deadline));
+
+	if ((stat & 0x1) == 0)
+		return 0;
+
+	return -1;
+}
+/**
+ * spinand_get_otp- send command 0xf to read the SPI Nand OTP register
+ * Description:
+ *   There is one bit( bit 0x10 ) to set or to clear the internal ECC.
+ *   Enable chip internal ECC, set the bit to 1
+ *   Disable chip internal ECC, clear the bit to 0
+ */
+static int spinand_get_otp(struct spi_device *spi_nand, u8 *otp)
+{
+	struct spinand_cmd cmd = {0};
+	int retval;
+
+	cmd.cmd = CMD_READ_REG;
+	cmd.n_addr = 1;
+	cmd.addr[0] = REG_OTP;
+	cmd.n_rx = 1;
+	cmd.rx_buf = otp;
+
+	retval = spinand_cmd(spi_nand, &cmd);
+	if (retval < 0)
+		dev_err(&spi_nand->dev, "error %d get otp\n", retval);
+	return retval;
+}
+
+/**
+ * spinand_set_otp- send command 0x1f to write the SPI Nand OTP register
+ * Description:
+ *   There is one bit( bit 0x10 ) to set or to clear the internal ECC.
+ *   Enable chip internal ECC, set the bit to 1
+ *   Disable chip internal ECC, clear the bit to 0
+ */
+static int spinand_set_otp(struct spi_device *spi_nand, u8 *otp)
+{
+	int retval;
+	struct spinand_cmd cmd = {0};
+
+	cmd.cmd = CMD_WRITE_REG,
+	cmd.n_addr = 1,
+	cmd.addr[0] = REG_OTP,
+	cmd.n_tx = 1,
+	cmd.tx_buf = otp,
+
+	retval = spinand_cmd(spi_nand, &cmd);
+	if (retval < 0)
+		dev_err(&spi_nand->dev, "error %d set otp\n", retval);
+
+	return retval;
+}
+
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+/**
+ * spinand_enable_ecc- send command 0x1f to write the SPI Nand OTP register
+ * Description:
+ *   There is one bit( bit 0x10 ) to set or to clear the internal ECC.
+ *   Enable chip internal ECC, set the bit to 1
+ *   Disable chip internal ECC, clear the bit to 0
+ */
+static int spinand_enable_ecc(struct spi_device *spi_nand)
+{
+	int retval;
+	u8 otp = 0;
+
+	retval = spinand_get_otp(spi_nand, &otp);
+	if (retval < 0)
+		return retval;
+
+	if ((otp & OTP_ECC_MASK) == OTP_ECC_MASK) {
+		return 0;
+	} else {
+		otp |= OTP_ECC_MASK;
+		retval = spinand_set_otp(spi_nand, &otp);
+		if (retval < 0)
+			return retval;
+		return spinand_get_otp(spi_nand, &otp);
+	}
+}
+#endif
+
+static int spinand_disable_ecc(struct spi_device *spi_nand)
+{
+	int retval;
+	u8 otp = 0;
+
+	retval = spinand_get_otp(spi_nand, &otp);
+	if (retval < 0)
+		return retval;
+
+	if ((otp & OTP_ECC_MASK) == OTP_ECC_MASK) {
+		otp &= ~OTP_ECC_MASK;
+		retval = spinand_set_otp(spi_nand, &otp);
+		if (retval < 0)
+			return retval;
+		return spinand_get_otp(spi_nand, &otp);
+	} else
+		return 0;
+}
+
+/**
+ * spinand_write_enable- send command 0x06 to enable write or erase the
+ * Nand cells
+ * Description:
+ *   Before write and erase the Nand cells, the write enable has to be set.
+ *   After the write or erase, the write enable bit is automatically
+ *   cleared (status register bit 2)
+ *   Set the bit 2 of the status register has the same effect
+ */
+static int spinand_write_enable(struct spi_device *spi_nand)
+{
+	struct spinand_cmd cmd = {0};
+
+	cmd.cmd = CMD_WR_ENABLE;
+	return spinand_cmd(spi_nand, &cmd);
+}
+
+static int spinand_read_page_to_cache(struct spi_device *spi_nand, u16 page_id)
+{
+	struct spinand_cmd cmd = {0};
+	u16 row;
+
+	row = page_id;
+	cmd.cmd = CMD_READ;
+	cmd.n_addr = 3;
+	cmd.addr[1] = (u8)((row & 0xff00) >> 8);
+	cmd.addr[2] = (u8)(row & 0x00ff);
+
+	return spinand_cmd(spi_nand, &cmd);
+}
+
+/*
+ * spinand_read_from_cache- send command 0x03 to read out the data from the
+ * cache register(2112 bytes max)
+ * Description:
+ *   The read can specify 1 to 2112 bytes of data read at the corresponding
+ *   locations.
+ *   No tRd delay.
+ */
+static int spinand_read_from_cache(struct spi_device *spi_nand, u16 page_id,
+		u16 byte_id, u16 len, u8 *rbuf)
+{
+	struct spinand_cmd cmd = {0};
+	u16 column;
+
+	column = byte_id;
+	cmd.cmd = CMD_READ_RDM;
+	cmd.n_addr = 3;
+	cmd.addr[0] = (u8)((column & 0xff00) >> 8);
+	cmd.addr[0] |= (u8)(((page_id >> 6) & 0x1) << 4);
+	cmd.addr[1] = (u8)(column & 0x00ff);
+	cmd.addr[2] = (u8)(0xff);
+	cmd.n_dummy = 0;
+	cmd.n_rx = len;
+	cmd.rx_buf = rbuf;
+
+	return spinand_cmd(spi_nand, &cmd);
+}
+
+/*
+ * spinand_read_page-to read a page with:
+ * @page_id: the physical page number
+ * @offset:  the location from 0 to 2111
+ * @len:     number of bytes to read
+ * @rbuf:    read buffer to hold @len bytes
+ *
+ * Description:
+ *   The read includes two commands to the Nand: 0x13 and 0x03 commands
+ *   Poll to read status to wait for tRD time.
+ */
+static int spinand_read_page(struct spi_device *spi_nand, u16 page_id,
+		u16 offset, u16 len, u8 *rbuf)
+{
+	int ret;
+	u8 status = 0;
+
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+	if (enable_read_hw_ecc) {
+		if (spinand_enable_ecc(spi_nand) < 0)
+			dev_err(&spi_nand->dev, "enable HW ECC failed!");
+	}
+#endif
+	ret = spinand_read_page_to_cache(spi_nand, page_id);
+	if (ret < 0)
+		return ret;
+
+	if (wait_till_ready(spi_nand))
+		dev_err(&spi_nand->dev, "WAIT timedout!!!\n");
+
+	while (1) {
+		ret = spinand_read_status(spi_nand, &status);
+		if (ret < 0) {
+			dev_err(&spi_nand->dev,
+					"err %d read status register\n", ret);
+			return ret;
+		}
+
+		if ((status & STATUS_OIP_MASK) == STATUS_READY) {
+			if ((status & STATUS_ECC_MASK) == STATUS_ECC_ERROR) {
+				dev_err(&spi_nand->dev, "ecc error, page=%d\n",
+						page_id);
+				return 0;
+			}
+			break;
+		}
+	}
+
+	ret = spinand_read_from_cache(spi_nand, page_id, offset, len, rbuf);
+	if (ret < 0) {
+		dev_err(&spi_nand->dev, "read from cache failed!!\n");
+		return ret;
+	}
+
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+	if (enable_read_hw_ecc) {
+		ret = spinand_disable_ecc(spi_nand);
+		if (ret < 0) {
+			dev_err(&spi_nand->dev, "disable ecc failed!!\n");
+			return ret;
+		}
+		enable_read_hw_ecc = 0;
+	}
+#endif
+	return ret;
+}
+
+/*
+ * spinand_program_data_to_cache--to write a page to cache with:
+ * @byte_id: the location to write to the cache
+ * @len:     number of bytes to write
+ * @rbuf:    read buffer to hold @len bytes
+ *
+ * Description:
+ *   The write command used here is 0x84--indicating that the cache is
+ *   not cleared first.
+ *   Since it is writing the data to cache, there is no tPROG time.
+ */
+static int spinand_program_data_to_cache(struct spi_device *spi_nand,
+		u16 page_id, u16 byte_id, u16 len, u8 *wbuf)
+{
+	struct spinand_cmd cmd = {0};
+	u16 column;
+
+	column = byte_id;
+	cmd.cmd = CMD_PROG_PAGE_CLRCACHE;
+	cmd.n_addr = 2;
+	cmd.addr[0] = (u8)((column & 0xff00) >> 8);
+	cmd.addr[0] |= (u8)(((page_id >> 6) & 0x1) << 4);
+	cmd.addr[1] = (u8)(column & 0x00ff);
+	cmd.n_tx = len;
+	cmd.tx_buf = wbuf;
+
+	return spinand_cmd(spi_nand, &cmd);
+}
+
+/**
+ * spinand_program_execute--to write a page from cache to the Nand array with
+ * @page_id: the physical page location to write the page.
+ *
+ * Description:
+ *   The write command used here is 0x10--indicating the cache is writing to
+ *   the Nand array.
+ *   Need to wait for tPROG time to finish the transaction.
+ */
+static int spinand_program_execute(struct spi_device *spi_nand, u16 page_id)
+{
+	struct spinand_cmd cmd = {0};
+	u16 row;
+
+	row = page_id;
+	cmd.cmd = CMD_PROG_PAGE_EXC;
+	cmd.n_addr = 3;
+	cmd.addr[1] = (u8)((row & 0xff00) >> 8);
+	cmd.addr[2] = (u8)(row & 0x00ff);
+
+	return spinand_cmd(spi_nand, &cmd);
+}
+
+/**
+ * spinand_program_page--to write a page with:
+ * @page_id: the physical page location to write the page.
+ * @offset:  the location from the cache starting from 0 to 2111
+ * @len:     the number of bytes to write
+ * @wbuf:    the buffer to hold the number of bytes
+ *
+ * Description:
+ *   The commands used here are 0x06, 0x84, and 0x10--indicating that
+ *   the write enable is first sent, the write cache command, and the
+ *   write execute command.
+ *   Poll to wait for the tPROG time to finish the transaction.
+ */
+static int spinand_program_page(struct spi_device *spi_nand,
+		u16 page_id, u16 offset, u16 len, u8 *buf)
+{
+	int retval;
+	u8 status = 0;
+	uint8_t *wbuf;
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+	unsigned int i, j;
+
+	enable_read_hw_ecc = 0;
+	wbuf = devm_kzalloc(&spi_nand->dev, CACHE_BUF, GFP_KERNEL);
+	spinand_read_page(spi_nand, page_id, 0, CACHE_BUF, wbuf);
+
+	for (i = offset, j = 0; i < len; i++, j++)
+		wbuf[i] &= buf[j];
+
+	if (enable_hw_ecc) {
+		retval = spinand_enable_ecc(spi_nand);
+		if (retval < 0) {
+			dev_err(&spi_nand->dev, "enable ecc failed!!\n");
+			return retval;
+		}
+	}
+#else
+	wbuf = buf;
+#endif
+	retval = spinand_write_enable(spi_nand);
+	if (retval < 0) {
+		dev_err(&spi_nand->dev, "write enable failed!!\n");
+		return retval;
+	}
+	if (wait_till_ready(spi_nand))
+		dev_err(&spi_nand->dev, "wait timedout!!!\n");
+
+	retval = spinand_program_data_to_cache(spi_nand, page_id,
+			offset, len, wbuf);
+	if (retval < 0)
+		return retval;
+	retval = spinand_program_execute(spi_nand, page_id);
+	if (retval < 0)
+		return retval;
+	while (1) {
+		retval = spinand_read_status(spi_nand, &status);
+		if (retval < 0) {
+			dev_err(&spi_nand->dev,
+					"error %d reading status register\n",
+					retval);
+			return retval;
+		}
+
+		if ((status & STATUS_OIP_MASK) == STATUS_READY) {
+			if ((status & STATUS_P_FAIL_MASK) == STATUS_P_FAIL) {
+				dev_err(&spi_nand->dev,
+					"program error, page %d\n", page_id);
+				return -1;
+			} else
+				break;
+		}
+	}
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+	if (enable_hw_ecc) {
+		retval = spinand_disable_ecc(spi_nand);
+		if (retval < 0) {
+			dev_err(&spi_nand->dev, "disable ecc failed!!\n");
+			return retval;
+		}
+		enable_hw_ecc = 0;
+	}
+#endif
+
+	return 0;
+}
+
+/**
+ * spinand_erase_block_erase--to erase a page with:
+ * @block_id: the physical block location to erase.
+ *
+ * Description:
+ *   The command used here is 0xd8--indicating an erase command to erase
+ *   one block--64 pages
+ *   Need to wait for tERS.
+ */
+static int spinand_erase_block_erase(struct spi_device *spi_nand, u16 block_id)
+{
+	struct spinand_cmd cmd = {0};
+	u16 row;
+
+	row = block_id;
+	cmd.cmd = CMD_ERASE_BLK;
+	cmd.n_addr = 3;
+	cmd.addr[1] = (u8)((row & 0xff00) >> 8);
+	cmd.addr[2] = (u8)(row & 0x00ff);
+
+	return spinand_cmd(spi_nand, &cmd);
+}
+
+/**
+ * spinand_erase_block--to erase a page with:
+ * @block_id: the physical block location to erase.
+ *
+ * Description:
+ *   The commands used here are 0x06 and 0xd8--indicating an erase
+ *   command to erase one block--64 pages
+ *   It will first to enable the write enable bit (0x06 command),
+ *   and then send the 0xd8 erase command
+ *   Poll to wait for the tERS time to complete the tranaction.
+ */
+static int spinand_erase_block(struct spi_device *spi_nand, u16 block_id)
+{
+	int retval;
+	u8 status = 0;
+
+	retval = spinand_write_enable(spi_nand);
+	if (wait_till_ready(spi_nand))
+		dev_err(&spi_nand->dev, "wait timedout!!!\n");
+
+	retval = spinand_erase_block_erase(spi_nand, block_id);
+	while (1) {
+		retval = spinand_read_status(spi_nand, &status);
+		if (retval < 0) {
+			dev_err(&spi_nand->dev,
+					"error %d reading status register\n",
+					(int) retval);
+			return retval;
+		}
+
+		if ((status & STATUS_OIP_MASK) == STATUS_READY) {
+			if ((status & STATUS_E_FAIL_MASK) == STATUS_E_FAIL) {
+				dev_err(&spi_nand->dev,
+					"erase error, block %d\n", block_id);
+				return -1;
+			} else
+				break;
+		}
+	}
+	return 0;
+}
+
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+static int spinand_write_page_hwecc(struct mtd_info *mtd,
+		struct nand_chip *chip, const uint8_t *buf, int oob_required)
+{
+	const uint8_t *p = buf;
+	int eccsize = chip->ecc.size;
+	int eccsteps = chip->ecc.steps;
+
+	enable_hw_ecc = 1;
+	chip->write_buf(mtd, p, eccsize * eccsteps);
+	return 0;
+}
+
+static int spinand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
+		uint8_t *buf, int oob_required, int page)
+{
+	u8 retval, status;
+	uint8_t *p = buf;
+	int eccsize = chip->ecc.size;
+	int eccsteps = chip->ecc.steps;
+	struct spinand_info *info = (struct spinand_info *)chip->priv;
+
+	enable_read_hw_ecc = 1;
+
+	chip->read_buf(mtd, p, eccsize * eccsteps);
+	if (oob_required)
+		chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	while (1) {
+		retval = spinand_read_status(info->spi, &status);
+		if ((status & STATUS_OIP_MASK) == STATUS_READY) {
+			if ((status & STATUS_ECC_MASK) == STATUS_ECC_ERROR) {
+				pr_info("spinand: ECC error\n");
+				mtd->ecc_stats.failed++;
+			} else if ((status & STATUS_ECC_MASK) ==
+					STATUS_ECC_1BIT_CORRECTED)
+				mtd->ecc_stats.corrected++;
+			break;
+		}
+	}
+	return 0;
+
+}
+#endif
+
+static void spinand_select_chip(struct mtd_info *mtd, int dev)
+{
+}
+
+static uint8_t spinand_read_byte(struct mtd_info *mtd)
+{
+	struct spinand_state *state = mtd_to_state(mtd);
+	u8 data;
+
+	data = state->buf[state->buf_ptr];
+	state->buf_ptr++;
+	return data;
+}
+
+
+static int spinand_wait(struct mtd_info *mtd, struct nand_chip *chip)
+{
+	struct spinand_info *info = (struct spinand_info *)chip->priv;
+
+	unsigned long timeo = jiffies;
+	int retval, state = chip->state;
+	u8 status;
+
+	if (state == FL_ERASING)
+		timeo += (HZ * 400) / 1000;
+	else
+		timeo += (HZ * 20) / 1000;
+
+	while (time_before(jiffies, timeo)) {
+		retval = spinand_read_status(info->spi, &status);
+		if ((status & STATUS_OIP_MASK) == STATUS_READY)
+			return 0;
+
+		cond_resched();
+	}
+	return 0;
+}
+
+static void spinand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+
+	struct spinand_state *state = mtd_to_state(mtd);
+	memcpy(state->buf + state->buf_ptr, buf, len);
+	state->buf_ptr += len;
+}
+
+static void spinand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+	struct spinand_state *state = mtd_to_state(mtd);
+	memcpy(buf, state->buf + state->buf_ptr, len);
+	state->buf_ptr += len;
+}
+
+/*
+ * spinand_reset- send RESET command "0xff" to the Nand device.
+ */
+static void spinand_reset(struct spi_device *spi_nand)
+{
+	struct spinand_cmd cmd = {0};
+
+	cmd.cmd = CMD_RESET;
+
+	if (spinand_cmd(spi_nand, &cmd) < 0)
+		pr_info("spinand reset failed!\n");
+
+	/* elapse 1ms before issuing any other command */
+	udelay(1000);
+
+	if (wait_till_ready(spi_nand))
+		dev_err(&spi_nand->dev, "wait timedout!\n");
+}
+
+static void spinand_cmdfunc(struct mtd_info *mtd, unsigned int command,
+		int column, int page)
+{
+	struct nand_chip *chip = (struct nand_chip *)mtd->priv;
+	struct spinand_info *info = (struct spinand_info *)chip->priv;
+	struct spinand_state *state = (struct spinand_state *)info->priv;
+
+	switch (command) {
+	/*
+	 * READ0 - read in first  0x800 bytes
+	 */
+	case NAND_CMD_READ1:
+	case NAND_CMD_READ0:
+		state->buf_ptr = 0;
+		spinand_read_page(info->spi, page, 0x0, 0x840, state->buf);
+		break;
+	/* READOOB reads only the OOB because no ECC is performed. */
+	case NAND_CMD_READOOB:
+		state->buf_ptr = 0;
+		spinand_read_page(info->spi, page, 0x800, 0x40, state->buf);
+		break;
+	case NAND_CMD_RNDOUT:
+		state->buf_ptr = column;
+		break;
+	case NAND_CMD_READID:
+		state->buf_ptr = 0;
+		spinand_read_id(info->spi, (u8 *)state->buf);
+		break;
+	case NAND_CMD_PARAM:
+		state->buf_ptr = 0;
+		break;
+	/* ERASE1 stores the block and page address */
+	case NAND_CMD_ERASE1:
+		spinand_erase_block(info->spi, page);
+		break;
+	/* ERASE2 uses the block and page address from ERASE1 */
+	case NAND_CMD_ERASE2:
+		break;
+	/* SEQIN sets up the addr buffer and all registers except the length */
+	case NAND_CMD_SEQIN:
+		state->col = column;
+		state->row = page;
+		state->buf_ptr = 0;
+		break;
+	/* PAGEPROG reuses all of the setup from SEQIN and adds the length */
+	case NAND_CMD_PAGEPROG:
+		spinand_program_page(info->spi, state->row, state->col,
+				state->buf_ptr, state->buf);
+		break;
+	case NAND_CMD_STATUS:
+		spinand_get_otp(info->spi, state->buf);
+		if (!(state->buf[0] & 0x80))
+			state->buf[0] = 0x80;
+		state->buf_ptr = 0;
+		break;
+	/* RESET command */
+	case NAND_CMD_RESET:
+		if (wait_till_ready(info->spi))
+			dev_err(&info->spi->dev, "WAIT timedout!!!\n");
+		/* a minimum of 250us must elapse before issuing RESET cmd*/
+		udelay(250);
+		spinand_reset(info->spi);
+		break;
+	default:
+		dev_err(&mtd->dev, "Unknown CMD: 0x%x\n", command);
+	}
+}
+
+/**
+ * spinand_lock_block- send write register 0x1f command to the Nand device
+ *
+ * Description:
+ *    After power up, all the Nand blocks are locked.  This function allows
+ *    one to unlock the blocks, and so it can be written or erased.
+ */
+static int spinand_lock_block(struct spi_device *spi_nand, u8 lock)
+{
+	struct spinand_cmd cmd = {0};
+	int ret;
+	u8 otp = 0;
+
+	ret = spinand_get_otp(spi_nand, &otp);
+
+	cmd.cmd = CMD_WRITE_REG;
+	cmd.n_addr = 1;
+	cmd.addr[0] = REG_BLOCK_LOCK;
+	cmd.n_tx = 1;
+	cmd.tx_buf = &lock;
+
+	ret = spinand_cmd(spi_nand, &cmd);
+	if (ret < 0)
+		dev_err(&spi_nand->dev, "error %d lock block\n", ret);
+
+	return ret;
+}
+/*
+ * spinand_probe - [spinand Interface]
+ * @spi_nand: registered device driver.
+ *
+ * Description:
+ *   To set up the device driver parameters to make the device available.
+ */
+static int spinand_probe(struct spi_device *spi_nand)
+{
+	struct mtd_info *mtd;
+	struct nand_chip *chip;
+	struct spinand_info *info;
+	struct spinand_state *state;
+	struct mtd_part_parser_data ppdata;
+
+	info  = devm_kzalloc(&spi_nand->dev, sizeof(struct spinand_info),
+			GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->spi = spi_nand;
+
+	spinand_lock_block(spi_nand, BL_ALL_UNLOCKED);
+
+	state = devm_kzalloc(&spi_nand->dev, sizeof(struct spinand_state),
+			GFP_KERNEL);
+	if (!state)
+		return -ENOMEM;
+
+	info->priv	= state;
+	state->buf_ptr	= 0;
+	state->buf	= devm_kzalloc(&spi_nand->dev, BUFSIZE, GFP_KERNEL);
+	if (!state->buf)
+		return -ENOMEM;
+
+	chip = devm_kzalloc(&spi_nand->dev, sizeof(struct nand_chip),
+			GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+#ifdef CONFIG_MTD_SPINAND_ONDIEECC
+	chip->ecc.mode	= NAND_ECC_HW;
+	chip->ecc.size	= 0x200;
+	chip->ecc.bytes	= 0x6;
+	chip->ecc.steps	= 0x4;
+
+	chip->ecc.strength = 1;
+	chip->ecc.total	= chip->ecc.steps * chip->ecc.bytes;
+	chip->ecc.layout = &spinand_oob_64;
+	chip->ecc.read_page = spinand_read_page_hwecc;
+	chip->ecc.write_page = spinand_write_page_hwecc;
+#else
+	chip->ecc.mode	= NAND_ECC_SOFT;
+	if (spinand_disable_ecc(spi_nand) < 0)
+		pr_info("%s: disable ecc failed!\n", __func__);
+#endif
+
+	chip->priv	= info;
+	chip->read_buf	= spinand_read_buf;
+	chip->write_buf	= spinand_write_buf;
+	chip->read_byte	= spinand_read_byte;
+	chip->cmdfunc	= spinand_cmdfunc;
+	chip->waitfunc	= spinand_wait;
+	chip->options	|= NAND_CACHEPRG;
+	chip->select_chip = spinand_select_chip;
+
+	mtd = devm_kzalloc(&spi_nand->dev, sizeof(struct mtd_info), GFP_KERNEL);
+	if (!mtd)
+		return -ENOMEM;
+
+	dev_set_drvdata(&spi_nand->dev, mtd);
+
+	mtd->priv = chip;
+	mtd->name = dev_name(&spi_nand->dev);
+	mtd->owner = THIS_MODULE;
+	mtd->oobsize = 64;
+
+	if (nand_scan(mtd, 1))
+		return -ENXIO;
+
+	ppdata.of_node = spi_nand->dev.of_node;
+	return mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
+}
+
+/*
+ * spinand_remove: Remove the device driver
+ * @spi: the spi device.
+ *
+ * Description:
+ *   To remove the device driver parameters and free up allocated memories.
+ */
+static int spinand_remove(struct spi_device *spi)
+{
+	mtd_device_unregister(dev_get_drvdata(&spi->dev));
+
+	return 0;
+}
+
+static const struct of_device_id spinand_dt[] = {
+	{ .compatible = "spinand,mt29f", },
+};
+
+/*
+ * Device name structure description
+ */
+static struct spi_driver spinand_driver = {
+	.driver = {
+		.name		= "mt29f",
+		.bus		= &spi_bus_type,
+		.owner		= THIS_MODULE,
+		.of_match_table	= spinand_dt,
+	},
+	.probe		= spinand_probe,
+	.remove		= spinand_remove,
+};
+
+/*
+ * Device driver registration
+ */
+static int __init spinand_init(void)
+{
+	return spi_register_driver(&spinand_driver);
+}
+
+/*
+ * unregister Device driver.
+ */
+static void __exit spinand_exit(void)
+{
+	spi_unregister_driver(&spinand_driver);
+}
+module_init(spinand_init);
+module_exit(spinand_exit);
+
+MODULE_DESCRIPTION("SPI NAND driver for Micron");
+MODULE_AUTHOR("Henry Pan <hspan@micron.com>, Kamlakant Patel <kamlakant.patel@broadcom.com>");
+MODULE_LICENSE("GPL v2");

drivers/staging/mt29f_spinand/mt29f_spinand.h

+/*-
+ * Copyright 2013 Broadcom Corporation
+ *
+ * Copyright (c) 2009-2010 Micron Technology, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ * Henry Pan <hspan@micron.com>
+ *
+ * based on nand.h
+ */
+#ifndef __LINUX_MTD_SPI_NAND_H
+#define __LINUX_MTD_SPI_NAND_H
+
+#include <linux/wait.h>
+#include <linux/spinlock.h>
+#include <linux/mtd/mtd.h>
+
+/* cmd */
+#define CMD_READ			0x13
+#define CMD_READ_RDM			0x03
+#define CMD_PROG_PAGE_CLRCACHE		0x02
+#define CMD_PROG_PAGE			0x84
+#define CMD_PROG_PAGE_EXC		0x10
+#define CMD_ERASE_BLK			0xd8
+#define CMD_WR_ENABLE			0x06
+#define CMD_WR_DISABLE			0x04
+#define CMD_READ_ID			0x9f
+#define CMD_RESET			0xff
+#define CMD_READ_REG			0x0f
+#define CMD_WRITE_REG			0x1f
+
+/* feature/ status reg */
+#define REG_BLOCK_LOCK			0xa0
+#define REG_OTP				0xb0
+#define REG_STATUS			0xc0/* timing */
+
+/* status */
+#define STATUS_OIP_MASK			0x01
+#define STATUS_READY			(0 << 0)
+#define STATUS_BUSY			(1 << 0)
+
+#define STATUS_E_FAIL_MASK		0x04
+#define STATUS_E_FAIL			(1 << 2)
+
+#define STATUS_P_FAIL_MASK		0x08
+#define STATUS_P_FAIL			(1 << 3)
+
+#define STATUS_ECC_MASK			0x30
+#define STATUS_ECC_1BIT_CORRECTED	(1 << 4)
+#define STATUS_ECC_ERROR		(2 << 4)
+#define STATUS_ECC_RESERVED		(3 << 4)
+
+/*ECC enable defines*/
+#define OTP_ECC_MASK			0x10
+#define OTP_ECC_OFF			0
+#define OTP_ECC_ON			1
+
+#define ECC_DISABLED
+#define ECC_IN_NAND
+#define ECC_SOFT
+
+/* block lock */
+#define BL_ALL_LOCKED      0x38
+#define BL_1_2_LOCKED      0x30
+#define BL_1_4_LOCKED      0x28
+#define BL_1_8_LOCKED      0x20
+#define BL_1_16_LOCKED     0x18
+#define BL_1_32_LOCKED     0x10
+#define BL_1_64_LOCKED     0x08
+#define BL_ALL_UNLOCKED    0
+
+struct spinand_info {
+	struct nand_ecclayout *ecclayout;
+	struct spi_device *spi;
+	void *priv;
+};
+
+struct spinand_state {
+	uint32_t	col;
+	uint32_t	row;
+	int		buf_ptr;
+	u8		*buf;
+};
+
+struct spinand_cmd {
+	u8		cmd;
+	u32		n_addr;		/* Number of address */
+	u8		addr[3];	/* Reg Offset */
+	u32		n_dummy;	/* Dummy use */
+	u32		n_tx;		/* Number of tx bytes */
+	u8		*tx_buf;	/* Tx buf */
+	u32		n_rx;		/* Number of rx bytes */
+	u8		*rx_buf;	/* Rx buf */
+};
+
+extern int spinand_mtd(struct mtd_info *mtd);
+extern void spinand_mtd_release(struct mtd_info *mtd);
+
+#endif /* __LINUX_MTD_SPI_NAND_H */