text: /*
   * drivers/mtd/nand/sharpsl.c
   *
   *  Copyright (C) 2004 Richard Purdie
   *  Copyright (C) 2008 Dmitry Baryshkov
   *
   *  Based on Sharp's NAND driver sharp_sl.c
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   */
  
  #include <linux/genhd.h>
  #include <linux/slab.h>
  #include <linux/module.h>
  #include <linux/delay.h>
  #include <linux/mtd/mtd.h>
  #include <linux/mtd/nand.h>
  #include <linux/mtd/nand_ecc.h>
  #include <linux/mtd/partitions.h>
  #include <linux/mtd/sharpsl.h>
  #include <linux/interrupt.h>
  #include <linux/platform_device.h>
  
  #include <asm/io.h>
  #include <mach/hardware.h>
  #include <asm/mach-types.h>
  
  struct sharpsl_nand {
  	struct nand_chip	chip;
  
  	void __iomem		*io;
  };
  
  static inline struct sharpsl_nand *mtd_to_sharpsl(struct mtd_info *mtd)
  {
  	return container_of(mtd_to_nand(mtd), struct sharpsl_nand, chip);
  }
  
  /* register offset */
  #define ECCLPLB		0x00	/* line parity 7 - 0 bit */
  #define ECCLPUB		0x04	/* line parity 15 - 8 bit */
  #define ECCCP		0x08	/* column parity 5 - 0 bit */
  #define ECCCNTR		0x0C	/* ECC byte counter */
  #define ECCCLRR		0x10	/* cleare ECC */
  #define FLASHIO		0x14	/* Flash I/O */
  #define FLASHCTL	0x18	/* Flash Control */
  
  /* Flash control bit */
  #define FLRYBY		(1 << 5)
  #define FLCE1		(1 << 4)
  #define FLWP		(1 << 3)
  #define FLALE		(1 << 2)
  #define FLCLE		(1 << 1)
  #define FLCE0		(1 << 0)
  
  /*
   *	hardware specific access to control-lines
   *	ctrl:
   *	NAND_CNE: bit 0 -> ! bit 0 & 4
   *	NAND_CLE: bit 1 -> bit 1
   *	NAND_ALE: bit 2 -> bit 2
   *
   */
  static void sharpsl_nand_hwcontrol(struct mtd_info *mtd, int cmd,
  				   unsigned int ctrl)
  {
  	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(mtd);
  	struct nand_chip *chip = mtd_to_nand(mtd);
  
  	if (ctrl & NAND_CTRL_CHANGE) {
  		unsigned char bits = ctrl & 0x07;
  
  		bits |= (ctrl & 0x01) << 4;
  
  		bits ^= 0x11;
  
  		writeb((readb(sharpsl->io + FLASHCTL) & ~0x17) | bits, sharpsl->io + FLASHCTL);
  	}
  
  	if (cmd != NAND_CMD_NONE)
  		writeb(cmd, chip->IO_ADDR_W);
  }
  
  static int sharpsl_nand_dev_ready(struct mtd_info *mtd)
  {
  	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(mtd);
  	return !((readb(sharpsl->io + FLASHCTL) & FLRYBY) == 0);
  }
  
  static void sharpsl_nand_enable_hwecc(struct mtd_info *mtd, int mode)
  {
  	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(mtd);
  	writeb(0, sharpsl->io + ECCCLRR);
  }
  
  static int sharpsl_nand_calculate_ecc(struct mtd_info *mtd, const u_char * dat, u_char * ecc_code)
  {
  	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(mtd);
  	ecc_code[0] = ~readb(sharpsl->io + ECCLPUB);
  	ecc_code[1] = ~readb(sharpsl->io + ECCLPLB);
  	ecc_code[2] = (~readb(sharpsl->io + ECCCP) << 2) | 0x03;
  	return readb(sharpsl->io + ECCCNTR) != 0;
  }
  
  /*
   * Main initialization routine
   */
  static int sharpsl_nand_probe(struct platform_device *pdev)
  {
  	struct nand_chip *this;
  	struct mtd_info *mtd;
  	struct resource *r;
  	int err = 0;
  	struct sharpsl_nand *sharpsl;
  	struct sharpsl_nand_platform_data *data = dev_get_platdata(&pdev->dev);
  
  	if (!data) {
  		dev_err(&pdev->dev, "no platform data!\n");
  		return -EINVAL;
  	}
  
  	/* Allocate memory for MTD device structure and private data */
  	sharpsl = kzalloc(sizeof(struct sharpsl_nand), GFP_KERNEL);
  	if (!sharpsl)
  		return -ENOMEM;
  
  	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!r) {
  		dev_err(&pdev->dev, "no io memory resource defined!\n");
  		err = -ENODEV;
  		goto err_get_res;
  	}
  
  	/* map physical address */
  	sharpsl->io = ioremap(r->start, resource_size(r));
  	if (!sharpsl->io) {
  		dev_err(&pdev->dev, "ioremap to access Sharp SL NAND chip failed\n");
  		err = -EIO;
  		goto err_ioremap;
  	}
  
  	/* Get pointer to private data */
  	this = (struct nand_chip *)(&sharpsl->chip);
  
  	/* Link the private data with the MTD structure */
  	mtd = nand_to_mtd(this);
  	mtd->dev.parent = &pdev->dev;
  
  	platform_set_drvdata(pdev, sharpsl);
  
  	/*
  	 * PXA initialize
  	 */
  	writeb(readb(sharpsl->io + FLASHCTL) | FLWP, sharpsl->io + FLASHCTL);
  
  	/* Set address of NAND IO lines */
  	this->IO_ADDR_R = sharpsl->io + FLASHIO;
  	this->IO_ADDR_W = sharpsl->io + FLASHIO;
  	/* Set address of hardware control function */
  	this->cmd_ctrl = sharpsl_nand_hwcontrol;
  	this->dev_ready = sharpsl_nand_dev_ready;
  	/* 15 us command delay time */
  	this->chip_delay = 15;
  	/* set eccmode using hardware ECC */
  	this->ecc.mode = NAND_ECC_HW;
  	this->ecc.size = 256;
  	this->ecc.bytes = 3;
  	this->ecc.strength = 1;
  	this->badblock_pattern = data->badblock_pattern;
  	this->ecc.layout = data->ecc_layout;
  	this->ecc.hwctl = sharpsl_nand_enable_hwecc;
  	this->ecc.calculate = sharpsl_nand_calculate_ecc;
  	this->ecc.correct = nand_correct_data;
  
  	/* Scan to find existence of the device */
  	err = nand_scan(mtd, 1);
  	if (err)
  		goto err_scan;
  
  	/* Register the partitions */
  	mtd->name = "sharpsl-nand";
  
  	err = mtd_device_parse_register(mtd, NULL, NULL,
  					data->partitions, data->nr_partitions);
  	if (err)
  		goto err_add;
  
  	/* Return happy */
  	return 0;
  
  err_add:
  	nand_release(mtd);
  
  err_scan:
  	iounmap(sharpsl->io);
  err_ioremap:
  err_get_res:
  	kfree(sharpsl);
  	return err;
  }
  
  /*
   * Clean up routine
   */
  static int sharpsl_nand_remove(struct platform_device *pdev)
  {
  	struct sharpsl_nand *sharpsl = platform_get_drvdata(pdev);
  
  	/* Release resources, unregister device */
  	nand_release(nand_to_mtd(&sharpsl->chip));
  
  	iounmap(sharpsl->io);
  
  	/* Free the MTD device structure */
  	kfree(sharpsl);
  
  	return 0;
  }
  
  static struct platform_driver sharpsl_nand_driver = {
  	.driver = {
  		.name	= "sharpsl-nand",
  	},
  	.probe		= sharpsl_nand_probe,
  	.remove		= sharpsl_nand_remove,
  };
  
  module_platform_driver(sharpsl_nand_driver);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
  MODULE_DESCRIPTION("Device specific logic for NAND flash on Sharp SL-C7xx Series");
  