s3c2410.c

老版本的mtd-snap

	writel(ctrl, info->regs + S3C2410_NFCONF);
}

static void s3c2440_nand_enable_hwecc(struct mtd_info *mtd, int mode)
{
	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
	unsigned long ctrl;

	ctrl = readl(info->regs + S3C2440_NFCONT);
	writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
}

static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd,
				      const u_char *dat, u_char *ecc_code)
{
	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);

	ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
	ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
	ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);

	pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n",
		 ecc_code[0], ecc_code[1], ecc_code[2]);

	return 0;
}


static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd,
				      const u_char *dat, u_char *ecc_code)
{
	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
	unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);

	ecc_code[0] = ecc;
	ecc_code[1] = ecc >> 8;
	ecc_code[2] = ecc >> 16;

	pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n",
		 ecc_code[0], ecc_code[1], ecc_code[2]);

	return 0;
}


/* over-ride the standard functions for a little more speed. We can
 * use read/write block to move the data buffers to/from the controller
*/

static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
	struct nand_chip *this = mtd->priv;
	readsb(this->IO_ADDR_R, buf, len);
}

static void s3c2410_nand_write_buf(struct mtd_info *mtd,
				   const u_char *buf, int len)
{
	struct nand_chip *this = mtd->priv;
	writesb(this->IO_ADDR_W, buf, len);
}

/* device management functions */

static int s3c2410_nand_remove(struct device *dev)
{
	struct s3c2410_nand_info *info = to_nand_info(dev);

	dev_set_drvdata(dev, NULL);

	if (info == NULL) 
		return 0;

	/* first thing we need to do is release all our mtds
	 * and their partitions, then go through freeing the
	 * resources used 
	 */
	
	if (info->mtds != NULL) {
		struct s3c2410_nand_mtd *ptr = info->mtds;
		int mtdno;

		for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
			pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
			nand_release(&ptr->mtd);
		}

		kfree(info->mtds);
	}

	/* free the common resources */

	if (info->clk != NULL && !IS_ERR(info->clk)) {
		clk_disable(info->clk);
		clk_unuse(info->clk);
		clk_put(info->clk);
	}

	if (info->regs != NULL) {
		iounmap(info->regs);
		info->regs = NULL;
	}

	if (info->area != NULL) {
		release_resource(info->area);
		kfree(info->area);
		info->area = NULL;
	}

	kfree(info);

	return 0;
}

#ifdef CONFIG_MTD_PARTITIONS
static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
				      struct s3c2410_nand_mtd *mtd,
				      struct s3c2410_nand_set *set)
{
	if (set == NULL)
		return add_mtd_device(&mtd->mtd);

	if (set->nr_partitions > 0 && set->partitions != NULL) {
		return add_mtd_partitions(&mtd->mtd,
					  set->partitions,
					  set->nr_partitions);
	}

	return add_mtd_device(&mtd->mtd);
}
#else
static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
				      struct s3c2410_nand_mtd *mtd,
				      struct s3c2410_nand_set *set)
{
	return add_mtd_device(&mtd->mtd);
}
#endif

/* s3c2410_nand_init_chip
 *
 * init a single instance of an chip 
*/

static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
				   struct s3c2410_nand_mtd *nmtd,
				   struct s3c2410_nand_set *set)
{
	struct nand_chip *chip = &nmtd->chip;

	chip->IO_ADDR_R	   = info->regs + S3C2410_NFDATA;
	chip->IO_ADDR_W    = info->regs + S3C2410_NFDATA;
	chip->hwcontrol    = s3c2410_nand_hwcontrol;
	chip->dev_ready    = s3c2410_nand_devready;
	chip->write_buf    = s3c2410_nand_write_buf;
	chip->read_buf     = s3c2410_nand_read_buf;
	chip->select_chip  = s3c2410_nand_select_chip;
	chip->chip_delay   = 50;
	chip->priv	   = nmtd;
	chip->options	   = 0;
	chip->controller   = &info->controller;

	if (info->is_s3c2440) {
		chip->IO_ADDR_R	 = info->regs + S3C2440_NFDATA;
		chip->IO_ADDR_W  = info->regs + S3C2440_NFDATA;
		chip->hwcontrol  = s3c2440_nand_hwcontrol;
	}

	nmtd->info	   = info;
	nmtd->mtd.priv	   = chip;
	nmtd->set	   = set;

	if (hardware_ecc) {
		chip->correct_data  = s3c2410_nand_correct_data;
		chip->enable_hwecc  = s3c2410_nand_enable_hwecc;
		chip->calculate_ecc = s3c2410_nand_calculate_ecc;
		chip->eccmode	    = NAND_ECC_HW3_512;
		chip->autooob       = &nand_hw_eccoob;

		if (info->is_s3c2440) {
			chip->enable_hwecc  = s3c2440_nand_enable_hwecc;
			chip->calculate_ecc = s3c2440_nand_calculate_ecc;
		}
	} else {
		chip->eccmode	    = NAND_ECC_SOFT;
	}
}

/* s3c2410_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 s3c24xx_nand_probe(struct device *dev, int is_s3c2440)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct s3c2410_platform_nand *plat = to_nand_plat(dev);
	struct s3c2410_nand_info *info;
	struct s3c2410_nand_mtd *nmtd;
	struct s3c2410_nand_set *sets;
	struct resource *res;
	int err = 0;
	int size;
	int nr_sets;
	int setno;

	pr_debug("s3c2410_nand_probe(%p)\n", dev);

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (info == NULL) {
		printk(KERN_ERR PFX "no memory for flash info\n");
		err = -ENOMEM;
		goto exit_error;
	}

	memzero(info, sizeof(*info));
	dev_set_drvdata(dev, info);

	spin_lock_init(&info->controller.lock);
	init_waitqueue_head(&info->controller.wq);

	/* get the clock source and enable it */

	info->clk = clk_get(dev, "nand");
	if (IS_ERR(info->clk)) {
		printk(KERN_ERR PFX "failed to get clock");
		err = -ENOENT;
		goto exit_error;
	}

	clk_use(info->clk);
	clk_enable(info->clk);

	/* allocate and map the resource */

	/* currently we assume we have the one resource */
	res  = pdev->resource;
	size = res->end - res->start + 1;

	info->area = request_mem_region(res->start, size, pdev->name);

	if (info->area == NULL) {
		printk(KERN_ERR PFX "cannot reserve register region\n");
		err = -ENOENT;
		goto exit_error;
	}

	info->device     = dev;
	info->platform   = plat;
	info->regs       = ioremap(res->start, size);
	info->is_s3c2440 = is_s3c2440;

	if (info->regs == NULL) {
		printk(KERN_ERR PFX "cannot reserve register region\n");
		err = -EIO;
		goto exit_error;
	}		

	printk(KERN_INFO PFX "mapped registers at %p\n", info->regs);

	/* initialise the hardware */

	err = s3c2410_nand_inithw(info, dev);
	if (err != 0)
		goto exit_error;

	sets = (plat != NULL) ? plat->sets : NULL;
	nr_sets = (plat != NULL) ? plat->nr_sets : 1;

	info->mtd_count = nr_sets;

	/* allocate our information */

	size = nr_sets * sizeof(*info->mtds);
	info->mtds = kmalloc(size, GFP_KERNEL);
	if (info->mtds == NULL) {
		printk(KERN_ERR PFX "failed to allocate mtd storage\n");
		err = -ENOMEM;
		goto exit_error;
	}

	memzero(info->mtds, size);

	/* initialise all possible chips */

	nmtd = info->mtds;

	for (setno = 0; setno < nr_sets; setno++, nmtd++) {
		pr_debug("initialising set %d (%p, info %p)\n",
			 setno, nmtd, info);
		
		s3c2410_nand_init_chip(info, nmtd, sets);

		nmtd->scan_res = nand_scan(&nmtd->mtd,
					   (sets) ? sets->nr_chips : 1);

		if (nmtd->scan_res == 0) {
			s3c2410_nand_add_partition(info, nmtd, sets);
		}

		if (sets != NULL)
			sets++;
	}
	
	pr_debug("initialised ok\n");
	return 0;

 exit_error:
	s3c2410_nand_remove(dev);

	if (err == 0)
		err = -EINVAL;
	return err;
}

/* driver device registration */

static int s3c2410_nand_probe(struct device *dev)
{
	return s3c24xx_nand_probe(dev, 0);
}

static int s3c2440_nand_probe(struct device *dev)
{
	return s3c24xx_nand_probe(dev, 1);
}

static struct device_driver s3c2410_nand_driver = {
	.name		= "s3c2410-nand",
	.bus		= &platform_bus_type,
	.probe		= s3c2410_nand_probe,
	.remove		= s3c2410_nand_remove,
};

static struct device_driver s3c2440_nand_driver = {
	.name		= "s3c2440-nand",
	.bus		= &platform_bus_type,
	.probe		= s3c2440_nand_probe,
	.remove		= s3c2410_nand_remove,
};

static int __init s3c2410_nand_init(void)
{
	printk("S3C24XX NAND Driver, (c) 2004 Simtec Electronics\n");

	driver_register(&s3c2440_nand_driver);
	return driver_register(&s3c2410_nand_driver);
}

static void __exit s3c2410_nand_exit(void)
{
	driver_unregister(&s3c2440_nand_driver);
	driver_unregister(&s3c2410_nand_driver);
}

module_init(s3c2410_nand_init);
module_exit(s3c2410_nand_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ben Dooks <[e-mail]>");
MODULE_DESCRIPTION("S3C24XX MTD NAND driver");