text: /*
   * Copyright (C) 2006-2007 PA Semi, Inc
   *
   * Author: Egor Martovetsky <egor@pasemi.com>
   * Maintained by: Olof Johansson <olof@lixom.net>
   *
   * Driver for the PWRficient onchip NAND flash interface
   *
   * 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.
   *
   * 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
   */
  
  #undef DEBUG
  
  #include <linux/slab.h>
  #include <linux/module.h>
  #include <linux/mtd/mtd.h>
  #include <linux/mtd/nand.h>
  #include <linux/mtd/nand_ecc.h>
  #include <linux/of_address.h>
  #include <linux/of_irq.h>
  #include <linux/of_platform.h>
  #include <linux/platform_device.h>
  #include <linux/pci.h>
  
  #include <asm/io.h>
  
  #define LBICTRL_LPCCTL_NR		0x00004000
  #define CLE_PIN_CTL			15
  #define ALE_PIN_CTL			14
  
  static unsigned int lpcctl;
  static struct mtd_info *pasemi_nand_mtd;
  static const char driver_name[] = "pasemi-nand";
  
  static void pasemi_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  {
  	struct nand_chip *chip = mtd->priv;
  
  	while (len > 0x800) {
  		memcpy_fromio(buf, chip->IO_ADDR_R, 0x800);
  		buf += 0x800;
  		len -= 0x800;
  	}
  	memcpy_fromio(buf, chip->IO_ADDR_R, len);
  }
  
  static void pasemi_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
  {
  	struct nand_chip *chip = mtd->priv;
  
  	while (len > 0x800) {
  		memcpy_toio(chip->IO_ADDR_R, buf, 0x800);
  		buf += 0x800;
  		len -= 0x800;
  	}
  	memcpy_toio(chip->IO_ADDR_R, buf, len);
  }
  
  static void pasemi_hwcontrol(struct mtd_info *mtd, int cmd,
  			     unsigned int ctrl)
  {
  	struct nand_chip *chip = mtd->priv;
  
  	if (cmd == NAND_CMD_NONE)
  		return;
  
  	if (ctrl & NAND_CLE)
  		out_8(chip->IO_ADDR_W + (1 << CLE_PIN_CTL), cmd);
  	else
  		out_8(chip->IO_ADDR_W + (1 << ALE_PIN_CTL), cmd);
  
  	/* Push out posted writes */
  	eieio();
  	inl(lpcctl);
  }
  
  int pasemi_device_ready(struct mtd_info *mtd)
  {
  	return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
  }
  
  static int pasemi_nand_probe(struct platform_device *ofdev)
  {
  	struct pci_dev *pdev;
  	struct device_node *np = ofdev->dev.of_node;
  	struct resource res;
  	struct nand_chip *chip;
  	int err = 0;
  
  	err = of_address_to_resource(np, 0, &res);
  
  	if (err)
  		return -EINVAL;
  
  	/* We only support one device at the moment */
  	if (pasemi_nand_mtd)
  		return -ENODEV;
  
  	pr_debug("pasemi_nand at %pR\n", &res);
  
  	/* Allocate memory for MTD device structure and private data */
  	pasemi_nand_mtd = kzalloc(sizeof(struct mtd_info) +
  				  sizeof(struct nand_chip), GFP_KERNEL);
  	if (!pasemi_nand_mtd) {
  		printk(KERN_WARNING
  		       "Unable to allocate PASEMI NAND MTD device structure\n");
  		err = -ENOMEM;
  		goto out;
  	}
  
  	/* Get pointer to private data */
  	chip = (struct nand_chip *)&pasemi_nand_mtd[1];
  
  	/* Link the private data with the MTD structure */
  	pasemi_nand_mtd->priv = chip;
  	pasemi_nand_mtd->owner = THIS_MODULE;
  
  	chip->IO_ADDR_R = of_iomap(np, 0);
  	chip->IO_ADDR_W = chip->IO_ADDR_R;
  
  	if (!chip->IO_ADDR_R) {
  		err = -EIO;
  		goto out_mtd;
  	}
  
  	pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
  	if (!pdev) {
  		err = -ENODEV;
  		goto out_ior;
  	}
  
  	lpcctl = pci_resource_start(pdev, 0);
  	pci_dev_put(pdev);
  
  	if (!request_region(lpcctl, 4, driver_name)) {
  		err = -EBUSY;
  		goto out_ior;
  	}
  
  	chip->cmd_ctrl = pasemi_hwcontrol;
  	chip->dev_ready = pasemi_device_ready;
  	chip->read_buf = pasemi_read_buf;
  	chip->write_buf = pasemi_write_buf;
  	chip->chip_delay = 0;
  	chip->ecc.mode = NAND_ECC_SOFT;
  
  	/* Enable the following for a flash based bad block table */
  	chip->bbt_options = NAND_BBT_USE_FLASH;
  
  	/* Scan to find existence of the device */
  	if (nand_scan(pasemi_nand_mtd, 1)) {
  		err = -ENXIO;
  		goto out_lpc;
  	}
  
  	if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
  		printk(KERN_ERR "pasemi_nand: Unable to register MTD device\n");
  		err = -ENODEV;
  		goto out_lpc;
  	}
  
  	printk(KERN_INFO "PA Semi NAND flash at %08llx, control at I/O %x\n",
  	       res.start, lpcctl);
  
  	return 0;
  
   out_lpc:
  	release_region(lpcctl, 4);
   out_ior:
  	iounmap(chip->IO_ADDR_R);
   out_mtd:
  	kfree(pasemi_nand_mtd);
   out:
  	return err;
  }
  
  static int pasemi_nand_remove(struct platform_device *ofdev)
  {
  	struct nand_chip *chip;
  
  	if (!pasemi_nand_mtd)
  		return 0;
  
  	chip = pasemi_nand_mtd->priv;
  
  	/* Release resources, unregister device */
  	nand_release(pasemi_nand_mtd);
  
  	release_region(lpcctl, 4);
  
  	iounmap(chip->IO_ADDR_R);
  
  	/* Free the MTD device structure */
  	kfree(pasemi_nand_mtd);
  
  	pasemi_nand_mtd = NULL;
  
  	return 0;
  }
  
  static const struct of_device_id pasemi_nand_match[] =
  {
  	{
  		.compatible   = "pasemi,localbus-nand",
  	},
  	{},
  };
  
  MODULE_DEVICE_TABLE(of, pasemi_nand_match);
  
  static struct platform_driver pasemi_nand_driver =
  {
  	.driver = {
  		.name = driver_name,
  		.of_match_table = pasemi_nand_match,
  	},
  	.probe		= pasemi_nand_probe,
  	.remove		= pasemi_nand_remove,
  };
  
  module_platform_driver(pasemi_nand_driver);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
  MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");
  